10263 lines
251 KiB
C
10263 lines
251 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Shared application/kernel submission and completion ring pairs, for
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* supporting fast/efficient IO.
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*
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* A note on the read/write ordering memory barriers that are matched between
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* the application and kernel side.
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*
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* After the application reads the CQ ring tail, it must use an
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* appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
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* before writing the tail (using smp_load_acquire to read the tail will
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* do). It also needs a smp_mb() before updating CQ head (ordering the
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* entry load(s) with the head store), pairing with an implicit barrier
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* through a control-dependency in io_get_cqe (smp_store_release to
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* store head will do). Failure to do so could lead to reading invalid
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* CQ entries.
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*
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* Likewise, the application must use an appropriate smp_wmb() before
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* writing the SQ tail (ordering SQ entry stores with the tail store),
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* which pairs with smp_load_acquire in io_get_sqring (smp_store_release
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* to store the tail will do). And it needs a barrier ordering the SQ
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* head load before writing new SQ entries (smp_load_acquire to read
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* head will do).
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*
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* When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
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* needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
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* updating the SQ tail; a full memory barrier smp_mb() is needed
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* between.
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*
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* Also see the examples in the liburing library:
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*
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* git://git.kernel.dk/liburing
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*
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* io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
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* from data shared between the kernel and application. This is done both
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* for ordering purposes, but also to ensure that once a value is loaded from
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* data that the application could potentially modify, it remains stable.
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*
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* Copyright (C) 2018-2019 Jens Axboe
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* Copyright (c) 2018-2019 Christoph Hellwig
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/errno.h>
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#include <linux/syscalls.h>
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#include <linux/compat.h>
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#include <net/compat.h>
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#include <linux/refcount.h>
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#include <linux/uio.h>
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#include <linux/bits.h>
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#include <linux/sched/signal.h>
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#include <linux/fs.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/percpu.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/bvec.h>
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#include <linux/net.h>
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#include <net/sock.h>
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#include <net/af_unix.h>
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#include <net/scm.h>
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#include <linux/anon_inodes.h>
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#include <linux/sched/mm.h>
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#include <linux/uaccess.h>
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#include <linux/nospec.h>
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#include <linux/sizes.h>
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#include <linux/hugetlb.h>
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#include <linux/highmem.h>
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#include <linux/namei.h>
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#include <linux/fsnotify.h>
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#include <linux/fadvise.h>
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#include <linux/eventpoll.h>
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#include <linux/splice.h>
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#include <linux/task_work.h>
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#include <linux/pagemap.h>
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#include <linux/io_uring.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/io_uring.h>
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#include <uapi/linux/io_uring.h>
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#include "internal.h"
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#include "io-wq.h"
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#define IORING_MAX_ENTRIES 32768
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#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
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#define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
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/*
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* Shift of 9 is 512 entries, or exactly one page on 64-bit archs
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*/
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#define IORING_FILE_TABLE_SHIFT 9
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#define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
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#define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
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#define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
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#define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
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IORING_REGISTER_LAST + IORING_OP_LAST)
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#define IO_RSRC_TAG_TABLE_SHIFT 9
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#define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
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#define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
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#define IORING_MAX_REG_BUFFERS (1U << 14)
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#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
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IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
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IOSQE_BUFFER_SELECT)
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#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
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REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
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#define IO_TCTX_REFS_CACHE_NR (1U << 10)
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struct io_uring {
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u32 head ____cacheline_aligned_in_smp;
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u32 tail ____cacheline_aligned_in_smp;
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};
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/*
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* This data is shared with the application through the mmap at offsets
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* IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
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*
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* The offsets to the member fields are published through struct
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* io_sqring_offsets when calling io_uring_setup.
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*/
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struct io_rings {
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/*
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* Head and tail offsets into the ring; the offsets need to be
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* masked to get valid indices.
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*
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* The kernel controls head of the sq ring and the tail of the cq ring,
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* and the application controls tail of the sq ring and the head of the
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* cq ring.
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*/
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struct io_uring sq, cq;
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/*
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* Bitmasks to apply to head and tail offsets (constant, equals
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* ring_entries - 1)
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*/
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u32 sq_ring_mask, cq_ring_mask;
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/* Ring sizes (constant, power of 2) */
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u32 sq_ring_entries, cq_ring_entries;
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/*
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* Number of invalid entries dropped by the kernel due to
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* invalid index stored in array
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*
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* Written by the kernel, shouldn't be modified by the
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* application (i.e. get number of "new events" by comparing to
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* cached value).
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*
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* After a new SQ head value was read by the application this
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* counter includes all submissions that were dropped reaching
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* the new SQ head (and possibly more).
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*/
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u32 sq_dropped;
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/*
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* Runtime SQ flags
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*
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* Written by the kernel, shouldn't be modified by the
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* application.
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*
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* The application needs a full memory barrier before checking
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* for IORING_SQ_NEED_WAKEUP after updating the sq tail.
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*/
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u32 sq_flags;
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/*
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* Runtime CQ flags
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*
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* Written by the application, shouldn't be modified by the
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* kernel.
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*/
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u32 cq_flags;
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/*
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* Number of completion events lost because the queue was full;
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* this should be avoided by the application by making sure
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* there are not more requests pending than there is space in
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* the completion queue.
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*
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* Written by the kernel, shouldn't be modified by the
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* application (i.e. get number of "new events" by comparing to
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* cached value).
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*
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* As completion events come in out of order this counter is not
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* ordered with any other data.
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*/
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u32 cq_overflow;
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/*
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* Ring buffer of completion events.
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*
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* The kernel writes completion events fresh every time they are
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* produced, so the application is allowed to modify pending
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* entries.
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*/
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struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
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};
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enum io_uring_cmd_flags {
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IO_URING_F_NONBLOCK = 1,
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IO_URING_F_COMPLETE_DEFER = 2,
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};
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struct io_mapped_ubuf {
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u64 ubuf;
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u64 ubuf_end;
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unsigned int nr_bvecs;
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unsigned long acct_pages;
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struct bio_vec bvec[];
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};
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struct io_ring_ctx;
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struct io_overflow_cqe {
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struct io_uring_cqe cqe;
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struct list_head list;
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};
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struct io_fixed_file {
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/* file * with additional FFS_* flags */
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unsigned long file_ptr;
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};
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struct io_rsrc_put {
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struct list_head list;
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u64 tag;
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union {
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void *rsrc;
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struct file *file;
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struct io_mapped_ubuf *buf;
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};
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};
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struct io_file_table {
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/* two level table */
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struct io_fixed_file **files;
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};
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struct io_rsrc_node {
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struct percpu_ref refs;
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struct list_head node;
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struct list_head rsrc_list;
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struct io_rsrc_data *rsrc_data;
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struct llist_node llist;
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bool done;
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};
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typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
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struct io_rsrc_data {
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struct io_ring_ctx *ctx;
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u64 **tags;
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unsigned int nr;
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rsrc_put_fn *do_put;
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atomic_t refs;
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struct completion done;
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bool quiesce;
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};
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struct io_buffer {
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struct list_head list;
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__u64 addr;
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__u32 len;
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__u16 bid;
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};
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struct io_restriction {
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DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
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DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
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u8 sqe_flags_allowed;
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u8 sqe_flags_required;
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bool registered;
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};
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enum {
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IO_SQ_THREAD_SHOULD_STOP = 0,
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IO_SQ_THREAD_SHOULD_PARK,
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};
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struct io_sq_data {
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refcount_t refs;
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atomic_t park_pending;
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struct mutex lock;
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/* ctx's that are using this sqd */
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struct list_head ctx_list;
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struct task_struct *thread;
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struct wait_queue_head wait;
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unsigned sq_thread_idle;
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int sq_cpu;
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pid_t task_pid;
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pid_t task_tgid;
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unsigned long state;
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struct completion exited;
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};
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#define IO_IOPOLL_BATCH 8
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#define IO_COMPL_BATCH 32
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#define IO_REQ_CACHE_SIZE 32
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#define IO_REQ_ALLOC_BATCH 8
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struct io_comp_state {
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struct io_kiocb *reqs[IO_COMPL_BATCH];
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unsigned int nr;
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/* inline/task_work completion list, under ->uring_lock */
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struct list_head free_list;
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};
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struct io_submit_link {
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struct io_kiocb *head;
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struct io_kiocb *last;
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};
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struct io_submit_state {
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struct blk_plug plug;
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struct io_submit_link link;
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/*
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* io_kiocb alloc cache
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*/
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void *reqs[IO_REQ_CACHE_SIZE];
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unsigned int free_reqs;
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bool plug_started;
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/*
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* Batch completion logic
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*/
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struct io_comp_state comp;
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/*
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* File reference cache
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*/
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struct file *file;
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unsigned int fd;
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unsigned int file_refs;
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unsigned int ios_left;
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};
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struct io_ring_ctx {
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/* const or read-mostly hot data */
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struct {
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struct percpu_ref refs;
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struct io_rings *rings;
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unsigned int flags;
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unsigned int compat: 1;
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unsigned int drain_next: 1;
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unsigned int eventfd_async: 1;
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unsigned int restricted: 1;
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unsigned int off_timeout_used: 1;
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unsigned int drain_active: 1;
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} ____cacheline_aligned_in_smp;
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/* submission data */
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struct {
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struct mutex uring_lock;
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/*
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* Ring buffer of indices into array of io_uring_sqe, which is
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* mmapped by the application using the IORING_OFF_SQES offset.
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*
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* This indirection could e.g. be used to assign fixed
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* io_uring_sqe entries to operations and only submit them to
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* the queue when needed.
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*
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* The kernel modifies neither the indices array nor the entries
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* array.
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*/
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u32 *sq_array;
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struct io_uring_sqe *sq_sqes;
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unsigned cached_sq_head;
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unsigned sq_entries;
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struct list_head defer_list;
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/*
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* Fixed resources fast path, should be accessed only under
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* uring_lock, and updated through io_uring_register(2)
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*/
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struct io_rsrc_node *rsrc_node;
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struct io_file_table file_table;
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unsigned nr_user_files;
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unsigned nr_user_bufs;
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struct io_mapped_ubuf **user_bufs;
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struct io_submit_state submit_state;
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struct list_head timeout_list;
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struct list_head cq_overflow_list;
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struct xarray io_buffers;
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struct xarray personalities;
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u32 pers_next;
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unsigned sq_thread_idle;
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} ____cacheline_aligned_in_smp;
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/* IRQ completion list, under ->completion_lock */
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struct list_head locked_free_list;
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unsigned int locked_free_nr;
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const struct cred *sq_creds; /* cred used for __io_sq_thread() */
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struct io_sq_data *sq_data; /* if using sq thread polling */
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struct wait_queue_head sqo_sq_wait;
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struct list_head sqd_list;
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unsigned long check_cq_overflow;
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struct {
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unsigned cached_cq_tail;
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unsigned cq_entries;
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struct eventfd_ctx *cq_ev_fd;
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struct wait_queue_head poll_wait;
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struct wait_queue_head cq_wait;
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unsigned cq_extra;
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atomic_t cq_timeouts;
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struct fasync_struct *cq_fasync;
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unsigned cq_last_tm_flush;
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} ____cacheline_aligned_in_smp;
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struct {
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spinlock_t completion_lock;
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/*
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* ->iopoll_list is protected by the ctx->uring_lock for
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* io_uring instances that don't use IORING_SETUP_SQPOLL.
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* For SQPOLL, only the single threaded io_sq_thread() will
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* manipulate the list, hence no extra locking is needed there.
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*/
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struct list_head iopoll_list;
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struct hlist_head *cancel_hash;
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unsigned cancel_hash_bits;
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bool poll_multi_queue;
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} ____cacheline_aligned_in_smp;
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struct io_restriction restrictions;
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/* slow path rsrc auxilary data, used by update/register */
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struct {
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struct io_rsrc_node *rsrc_backup_node;
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struct io_mapped_ubuf *dummy_ubuf;
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struct io_rsrc_data *file_data;
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struct io_rsrc_data *buf_data;
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struct delayed_work rsrc_put_work;
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struct llist_head rsrc_put_llist;
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struct list_head rsrc_ref_list;
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spinlock_t rsrc_ref_lock;
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};
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/* Keep this last, we don't need it for the fast path */
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struct {
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#if defined(CONFIG_UNIX)
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struct socket *ring_sock;
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#endif
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/* hashed buffered write serialization */
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struct io_wq_hash *hash_map;
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/* Only used for accounting purposes */
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struct user_struct *user;
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struct mm_struct *mm_account;
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/* ctx exit and cancelation */
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struct llist_head fallback_llist;
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struct delayed_work fallback_work;
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struct work_struct exit_work;
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struct list_head tctx_list;
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struct completion ref_comp;
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};
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};
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struct io_uring_task {
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/* submission side */
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int cached_refs;
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struct xarray xa;
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struct wait_queue_head wait;
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const struct io_ring_ctx *last;
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struct io_wq *io_wq;
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struct percpu_counter inflight;
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atomic_t inflight_tracked;
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atomic_t in_idle;
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spinlock_t task_lock;
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struct io_wq_work_list task_list;
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unsigned long task_state;
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struct callback_head task_work;
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};
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/*
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* First field must be the file pointer in all the
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* iocb unions! See also 'struct kiocb' in <linux/fs.h>
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*/
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struct io_poll_iocb {
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struct file *file;
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struct wait_queue_head *head;
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__poll_t events;
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bool done;
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bool canceled;
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struct wait_queue_entry wait;
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};
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struct io_poll_update {
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struct file *file;
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u64 old_user_data;
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u64 new_user_data;
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__poll_t events;
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bool update_events;
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bool update_user_data;
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};
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struct io_close {
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struct file *file;
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int fd;
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};
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|
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struct io_timeout_data {
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struct io_kiocb *req;
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struct hrtimer timer;
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struct timespec64 ts;
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enum hrtimer_mode mode;
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};
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|
|
struct io_accept {
|
|
struct file *file;
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|
struct sockaddr __user *addr;
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|
int __user *addr_len;
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int flags;
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|
unsigned long nofile;
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};
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|
|
struct io_sync {
|
|
struct file *file;
|
|
loff_t len;
|
|
loff_t off;
|
|
int flags;
|
|
int mode;
|
|
};
|
|
|
|
struct io_cancel {
|
|
struct file *file;
|
|
u64 addr;
|
|
};
|
|
|
|
struct io_timeout {
|
|
struct file *file;
|
|
u32 off;
|
|
u32 target_seq;
|
|
struct list_head list;
|
|
/* head of the link, used by linked timeouts only */
|
|
struct io_kiocb *head;
|
|
};
|
|
|
|
struct io_timeout_rem {
|
|
struct file *file;
|
|
u64 addr;
|
|
|
|
/* timeout update */
|
|
struct timespec64 ts;
|
|
u32 flags;
|
|
};
|
|
|
|
struct io_rw {
|
|
/* NOTE: kiocb has the file as the first member, so don't do it here */
|
|
struct kiocb kiocb;
|
|
u64 addr;
|
|
u64 len;
|
|
};
|
|
|
|
struct io_connect {
|
|
struct file *file;
|
|
struct sockaddr __user *addr;
|
|
int addr_len;
|
|
};
|
|
|
|
struct io_sr_msg {
|
|
struct file *file;
|
|
union {
|
|
struct compat_msghdr __user *umsg_compat;
|
|
struct user_msghdr __user *umsg;
|
|
void __user *buf;
|
|
};
|
|
int msg_flags;
|
|
int bgid;
|
|
size_t len;
|
|
struct io_buffer *kbuf;
|
|
};
|
|
|
|
struct io_open {
|
|
struct file *file;
|
|
int dfd;
|
|
struct filename *filename;
|
|
struct open_how how;
|
|
unsigned long nofile;
|
|
};
|
|
|
|
struct io_rsrc_update {
|
|
struct file *file;
|
|
u64 arg;
|
|
u32 nr_args;
|
|
u32 offset;
|
|
};
|
|
|
|
struct io_fadvise {
|
|
struct file *file;
|
|
u64 offset;
|
|
u32 len;
|
|
u32 advice;
|
|
};
|
|
|
|
struct io_madvise {
|
|
struct file *file;
|
|
u64 addr;
|
|
u32 len;
|
|
u32 advice;
|
|
};
|
|
|
|
struct io_epoll {
|
|
struct file *file;
|
|
int epfd;
|
|
int op;
|
|
int fd;
|
|
struct epoll_event event;
|
|
};
|
|
|
|
struct io_splice {
|
|
struct file *file_out;
|
|
struct file *file_in;
|
|
loff_t off_out;
|
|
loff_t off_in;
|
|
u64 len;
|
|
unsigned int flags;
|
|
};
|
|
|
|
struct io_provide_buf {
|
|
struct file *file;
|
|
__u64 addr;
|
|
__u32 len;
|
|
__u32 bgid;
|
|
__u16 nbufs;
|
|
__u16 bid;
|
|
};
|
|
|
|
struct io_statx {
|
|
struct file *file;
|
|
int dfd;
|
|
unsigned int mask;
|
|
unsigned int flags;
|
|
const char __user *filename;
|
|
struct statx __user *buffer;
|
|
};
|
|
|
|
struct io_shutdown {
|
|
struct file *file;
|
|
int how;
|
|
};
|
|
|
|
struct io_rename {
|
|
struct file *file;
|
|
int old_dfd;
|
|
int new_dfd;
|
|
struct filename *oldpath;
|
|
struct filename *newpath;
|
|
int flags;
|
|
};
|
|
|
|
struct io_unlink {
|
|
struct file *file;
|
|
int dfd;
|
|
int flags;
|
|
struct filename *filename;
|
|
};
|
|
|
|
struct io_completion {
|
|
struct file *file;
|
|
struct list_head list;
|
|
u32 cflags;
|
|
};
|
|
|
|
struct io_async_connect {
|
|
struct sockaddr_storage address;
|
|
};
|
|
|
|
struct io_async_msghdr {
|
|
struct iovec fast_iov[UIO_FASTIOV];
|
|
/* points to an allocated iov, if NULL we use fast_iov instead */
|
|
struct iovec *free_iov;
|
|
struct sockaddr __user *uaddr;
|
|
struct msghdr msg;
|
|
struct sockaddr_storage addr;
|
|
};
|
|
|
|
struct io_async_rw {
|
|
struct iovec fast_iov[UIO_FASTIOV];
|
|
const struct iovec *free_iovec;
|
|
struct iov_iter iter;
|
|
size_t bytes_done;
|
|
struct wait_page_queue wpq;
|
|
};
|
|
|
|
enum {
|
|
REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
|
|
REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
|
|
REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
|
|
REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
|
|
REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
|
|
REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
|
|
|
|
/* first byte is taken by user flags, shift it to not overlap */
|
|
REQ_F_FAIL_BIT = 8,
|
|
REQ_F_INFLIGHT_BIT,
|
|
REQ_F_CUR_POS_BIT,
|
|
REQ_F_NOWAIT_BIT,
|
|
REQ_F_LINK_TIMEOUT_BIT,
|
|
REQ_F_NEED_CLEANUP_BIT,
|
|
REQ_F_POLLED_BIT,
|
|
REQ_F_BUFFER_SELECTED_BIT,
|
|
REQ_F_LTIMEOUT_ACTIVE_BIT,
|
|
REQ_F_COMPLETE_INLINE_BIT,
|
|
REQ_F_REISSUE_BIT,
|
|
REQ_F_DONT_REISSUE_BIT,
|
|
REQ_F_CREDS_BIT,
|
|
/* keep async read/write and isreg together and in order */
|
|
REQ_F_ASYNC_READ_BIT,
|
|
REQ_F_ASYNC_WRITE_BIT,
|
|
REQ_F_ISREG_BIT,
|
|
|
|
/* not a real bit, just to check we're not overflowing the space */
|
|
__REQ_F_LAST_BIT,
|
|
};
|
|
|
|
enum {
|
|
/* ctx owns file */
|
|
REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
|
|
/* drain existing IO first */
|
|
REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
|
|
/* linked sqes */
|
|
REQ_F_LINK = BIT(REQ_F_LINK_BIT),
|
|
/* doesn't sever on completion < 0 */
|
|
REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
|
|
/* IOSQE_ASYNC */
|
|
REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
|
|
/* IOSQE_BUFFER_SELECT */
|
|
REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
|
|
|
|
/* fail rest of links */
|
|
REQ_F_FAIL = BIT(REQ_F_FAIL_BIT),
|
|
/* on inflight list, should be cancelled and waited on exit reliably */
|
|
REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
|
|
/* read/write uses file position */
|
|
REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
|
|
/* must not punt to workers */
|
|
REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
|
|
/* has or had linked timeout */
|
|
REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
|
|
/* needs cleanup */
|
|
REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
|
|
/* already went through poll handler */
|
|
REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
|
|
/* buffer already selected */
|
|
REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
|
|
/* linked timeout is active, i.e. prepared by link's head */
|
|
REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
|
|
/* completion is deferred through io_comp_state */
|
|
REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
|
|
/* caller should reissue async */
|
|
REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
|
|
/* don't attempt request reissue, see io_rw_reissue() */
|
|
REQ_F_DONT_REISSUE = BIT(REQ_F_DONT_REISSUE_BIT),
|
|
/* supports async reads */
|
|
REQ_F_ASYNC_READ = BIT(REQ_F_ASYNC_READ_BIT),
|
|
/* supports async writes */
|
|
REQ_F_ASYNC_WRITE = BIT(REQ_F_ASYNC_WRITE_BIT),
|
|
/* regular file */
|
|
REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
|
|
/* has creds assigned */
|
|
REQ_F_CREDS = BIT(REQ_F_CREDS_BIT),
|
|
};
|
|
|
|
struct async_poll {
|
|
struct io_poll_iocb poll;
|
|
struct io_poll_iocb *double_poll;
|
|
};
|
|
|
|
typedef void (*io_req_tw_func_t)(struct io_kiocb *req);
|
|
|
|
struct io_task_work {
|
|
union {
|
|
struct io_wq_work_node node;
|
|
struct llist_node fallback_node;
|
|
};
|
|
io_req_tw_func_t func;
|
|
};
|
|
|
|
enum {
|
|
IORING_RSRC_FILE = 0,
|
|
IORING_RSRC_BUFFER = 1,
|
|
};
|
|
|
|
/*
|
|
* NOTE! Each of the iocb union members has the file pointer
|
|
* as the first entry in their struct definition. So you can
|
|
* access the file pointer through any of the sub-structs,
|
|
* or directly as just 'ki_filp' in this struct.
|
|
*/
|
|
struct io_kiocb {
|
|
union {
|
|
struct file *file;
|
|
struct io_rw rw;
|
|
struct io_poll_iocb poll;
|
|
struct io_poll_update poll_update;
|
|
struct io_accept accept;
|
|
struct io_sync sync;
|
|
struct io_cancel cancel;
|
|
struct io_timeout timeout;
|
|
struct io_timeout_rem timeout_rem;
|
|
struct io_connect connect;
|
|
struct io_sr_msg sr_msg;
|
|
struct io_open open;
|
|
struct io_close close;
|
|
struct io_rsrc_update rsrc_update;
|
|
struct io_fadvise fadvise;
|
|
struct io_madvise madvise;
|
|
struct io_epoll epoll;
|
|
struct io_splice splice;
|
|
struct io_provide_buf pbuf;
|
|
struct io_statx statx;
|
|
struct io_shutdown shutdown;
|
|
struct io_rename rename;
|
|
struct io_unlink unlink;
|
|
/* use only after cleaning per-op data, see io_clean_op() */
|
|
struct io_completion compl;
|
|
};
|
|
|
|
/* opcode allocated if it needs to store data for async defer */
|
|
void *async_data;
|
|
u8 opcode;
|
|
/* polled IO has completed */
|
|
u8 iopoll_completed;
|
|
|
|
u16 buf_index;
|
|
u32 result;
|
|
|
|
struct io_ring_ctx *ctx;
|
|
unsigned int flags;
|
|
atomic_t refs;
|
|
struct task_struct *task;
|
|
u64 user_data;
|
|
|
|
struct io_kiocb *link;
|
|
struct percpu_ref *fixed_rsrc_refs;
|
|
|
|
/* used with ctx->iopoll_list with reads/writes */
|
|
struct list_head inflight_entry;
|
|
struct io_task_work io_task_work;
|
|
/* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
|
|
struct hlist_node hash_node;
|
|
struct async_poll *apoll;
|
|
struct io_wq_work work;
|
|
const struct cred *creds;
|
|
|
|
/* store used ubuf, so we can prevent reloading */
|
|
struct io_mapped_ubuf *imu;
|
|
};
|
|
|
|
struct io_tctx_node {
|
|
struct list_head ctx_node;
|
|
struct task_struct *task;
|
|
struct io_ring_ctx *ctx;
|
|
};
|
|
|
|
struct io_defer_entry {
|
|
struct list_head list;
|
|
struct io_kiocb *req;
|
|
u32 seq;
|
|
};
|
|
|
|
struct io_op_def {
|
|
/* needs req->file assigned */
|
|
unsigned needs_file : 1;
|
|
/* hash wq insertion if file is a regular file */
|
|
unsigned hash_reg_file : 1;
|
|
/* unbound wq insertion if file is a non-regular file */
|
|
unsigned unbound_nonreg_file : 1;
|
|
/* opcode is not supported by this kernel */
|
|
unsigned not_supported : 1;
|
|
/* set if opcode supports polled "wait" */
|
|
unsigned pollin : 1;
|
|
unsigned pollout : 1;
|
|
/* op supports buffer selection */
|
|
unsigned buffer_select : 1;
|
|
/* do prep async if is going to be punted */
|
|
unsigned needs_async_setup : 1;
|
|
/* should block plug */
|
|
unsigned plug : 1;
|
|
/* size of async data needed, if any */
|
|
unsigned short async_size;
|
|
};
|
|
|
|
static const struct io_op_def io_op_defs[] = {
|
|
[IORING_OP_NOP] = {},
|
|
[IORING_OP_READV] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
.buffer_select = 1,
|
|
.needs_async_setup = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_WRITEV] = {
|
|
.needs_file = 1,
|
|
.hash_reg_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
.needs_async_setup = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_FSYNC] = {
|
|
.needs_file = 1,
|
|
},
|
|
[IORING_OP_READ_FIXED] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_WRITE_FIXED] = {
|
|
.needs_file = 1,
|
|
.hash_reg_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_POLL_ADD] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
},
|
|
[IORING_OP_POLL_REMOVE] = {},
|
|
[IORING_OP_SYNC_FILE_RANGE] = {
|
|
.needs_file = 1,
|
|
},
|
|
[IORING_OP_SENDMSG] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
.needs_async_setup = 1,
|
|
.async_size = sizeof(struct io_async_msghdr),
|
|
},
|
|
[IORING_OP_RECVMSG] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
.buffer_select = 1,
|
|
.needs_async_setup = 1,
|
|
.async_size = sizeof(struct io_async_msghdr),
|
|
},
|
|
[IORING_OP_TIMEOUT] = {
|
|
.async_size = sizeof(struct io_timeout_data),
|
|
},
|
|
[IORING_OP_TIMEOUT_REMOVE] = {
|
|
/* used by timeout updates' prep() */
|
|
},
|
|
[IORING_OP_ACCEPT] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
},
|
|
[IORING_OP_ASYNC_CANCEL] = {},
|
|
[IORING_OP_LINK_TIMEOUT] = {
|
|
.async_size = sizeof(struct io_timeout_data),
|
|
},
|
|
[IORING_OP_CONNECT] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
.needs_async_setup = 1,
|
|
.async_size = sizeof(struct io_async_connect),
|
|
},
|
|
[IORING_OP_FALLOCATE] = {
|
|
.needs_file = 1,
|
|
},
|
|
[IORING_OP_OPENAT] = {},
|
|
[IORING_OP_CLOSE] = {},
|
|
[IORING_OP_FILES_UPDATE] = {},
|
|
[IORING_OP_STATX] = {},
|
|
[IORING_OP_READ] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
.buffer_select = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_WRITE] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
.plug = 1,
|
|
.async_size = sizeof(struct io_async_rw),
|
|
},
|
|
[IORING_OP_FADVISE] = {
|
|
.needs_file = 1,
|
|
},
|
|
[IORING_OP_MADVISE] = {},
|
|
[IORING_OP_SEND] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollout = 1,
|
|
},
|
|
[IORING_OP_RECV] = {
|
|
.needs_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
.pollin = 1,
|
|
.buffer_select = 1,
|
|
},
|
|
[IORING_OP_OPENAT2] = {
|
|
},
|
|
[IORING_OP_EPOLL_CTL] = {
|
|
.unbound_nonreg_file = 1,
|
|
},
|
|
[IORING_OP_SPLICE] = {
|
|
.needs_file = 1,
|
|
.hash_reg_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
},
|
|
[IORING_OP_PROVIDE_BUFFERS] = {},
|
|
[IORING_OP_REMOVE_BUFFERS] = {},
|
|
[IORING_OP_TEE] = {
|
|
.needs_file = 1,
|
|
.hash_reg_file = 1,
|
|
.unbound_nonreg_file = 1,
|
|
},
|
|
[IORING_OP_SHUTDOWN] = {
|
|
.needs_file = 1,
|
|
},
|
|
[IORING_OP_RENAMEAT] = {},
|
|
[IORING_OP_UNLINKAT] = {},
|
|
};
|
|
|
|
static bool io_disarm_next(struct io_kiocb *req);
|
|
static void io_uring_del_tctx_node(unsigned long index);
|
|
static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
|
|
struct task_struct *task,
|
|
bool cancel_all);
|
|
static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
|
|
static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx);
|
|
|
|
static bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
|
|
long res, unsigned int cflags);
|
|
static void io_put_req(struct io_kiocb *req);
|
|
static void io_put_req_deferred(struct io_kiocb *req, int nr);
|
|
static void io_dismantle_req(struct io_kiocb *req);
|
|
static void io_put_task(struct task_struct *task, int nr);
|
|
static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req);
|
|
static void io_queue_linked_timeout(struct io_kiocb *req);
|
|
static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
|
|
struct io_uring_rsrc_update2 *up,
|
|
unsigned nr_args);
|
|
static void io_clean_op(struct io_kiocb *req);
|
|
static struct file *io_file_get(struct io_submit_state *state,
|
|
struct io_kiocb *req, int fd, bool fixed);
|
|
static void __io_queue_sqe(struct io_kiocb *req);
|
|
static void io_rsrc_put_work(struct work_struct *work);
|
|
|
|
static void io_req_task_queue(struct io_kiocb *req);
|
|
static void io_submit_flush_completions(struct io_ring_ctx *ctx);
|
|
static bool io_poll_remove_waitqs(struct io_kiocb *req);
|
|
static int io_req_prep_async(struct io_kiocb *req);
|
|
|
|
static void io_fallback_req_func(struct work_struct *unused);
|
|
|
|
static struct kmem_cache *req_cachep;
|
|
|
|
static const struct file_operations io_uring_fops;
|
|
|
|
struct sock *io_uring_get_socket(struct file *file)
|
|
{
|
|
#if defined(CONFIG_UNIX)
|
|
if (file->f_op == &io_uring_fops) {
|
|
struct io_ring_ctx *ctx = file->private_data;
|
|
|
|
return ctx->ring_sock->sk;
|
|
}
|
|
#endif
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(io_uring_get_socket);
|
|
|
|
#define io_for_each_link(pos, head) \
|
|
for (pos = (head); pos; pos = pos->link)
|
|
|
|
static inline void io_req_set_rsrc_node(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (!req->fixed_rsrc_refs) {
|
|
req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
|
|
percpu_ref_get(req->fixed_rsrc_refs);
|
|
}
|
|
}
|
|
|
|
static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
|
|
{
|
|
bool got = percpu_ref_tryget(ref);
|
|
|
|
/* already at zero, wait for ->release() */
|
|
if (!got)
|
|
wait_for_completion(compl);
|
|
percpu_ref_resurrect(ref);
|
|
if (got)
|
|
percpu_ref_put(ref);
|
|
}
|
|
|
|
static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
|
|
bool cancel_all)
|
|
{
|
|
struct io_kiocb *req;
|
|
|
|
if (task && head->task != task)
|
|
return false;
|
|
if (cancel_all)
|
|
return true;
|
|
|
|
io_for_each_link(req, head) {
|
|
if (req->flags & REQ_F_INFLIGHT)
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static inline void req_set_fail(struct io_kiocb *req)
|
|
{
|
|
req->flags |= REQ_F_FAIL;
|
|
}
|
|
|
|
static void io_ring_ctx_ref_free(struct percpu_ref *ref)
|
|
{
|
|
struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
|
|
|
|
complete(&ctx->ref_comp);
|
|
}
|
|
|
|
static inline bool io_is_timeout_noseq(struct io_kiocb *req)
|
|
{
|
|
return !req->timeout.off;
|
|
}
|
|
|
|
static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
int hash_bits;
|
|
|
|
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
|
|
if (!ctx)
|
|
return NULL;
|
|
|
|
/*
|
|
* Use 5 bits less than the max cq entries, that should give us around
|
|
* 32 entries per hash list if totally full and uniformly spread.
|
|
*/
|
|
hash_bits = ilog2(p->cq_entries);
|
|
hash_bits -= 5;
|
|
if (hash_bits <= 0)
|
|
hash_bits = 1;
|
|
ctx->cancel_hash_bits = hash_bits;
|
|
ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
|
|
GFP_KERNEL);
|
|
if (!ctx->cancel_hash)
|
|
goto err;
|
|
__hash_init(ctx->cancel_hash, 1U << hash_bits);
|
|
|
|
ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
|
|
if (!ctx->dummy_ubuf)
|
|
goto err;
|
|
/* set invalid range, so io_import_fixed() fails meeting it */
|
|
ctx->dummy_ubuf->ubuf = -1UL;
|
|
|
|
if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
|
|
PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
|
|
goto err;
|
|
|
|
ctx->flags = p->flags;
|
|
init_waitqueue_head(&ctx->sqo_sq_wait);
|
|
INIT_LIST_HEAD(&ctx->sqd_list);
|
|
init_waitqueue_head(&ctx->poll_wait);
|
|
INIT_LIST_HEAD(&ctx->cq_overflow_list);
|
|
init_completion(&ctx->ref_comp);
|
|
xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
|
|
xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
|
|
mutex_init(&ctx->uring_lock);
|
|
init_waitqueue_head(&ctx->cq_wait);
|
|
spin_lock_init(&ctx->completion_lock);
|
|
INIT_LIST_HEAD(&ctx->iopoll_list);
|
|
INIT_LIST_HEAD(&ctx->defer_list);
|
|
INIT_LIST_HEAD(&ctx->timeout_list);
|
|
spin_lock_init(&ctx->rsrc_ref_lock);
|
|
INIT_LIST_HEAD(&ctx->rsrc_ref_list);
|
|
INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
|
|
init_llist_head(&ctx->rsrc_put_llist);
|
|
INIT_LIST_HEAD(&ctx->tctx_list);
|
|
INIT_LIST_HEAD(&ctx->submit_state.comp.free_list);
|
|
INIT_LIST_HEAD(&ctx->locked_free_list);
|
|
INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
|
|
return ctx;
|
|
err:
|
|
kfree(ctx->dummy_ubuf);
|
|
kfree(ctx->cancel_hash);
|
|
kfree(ctx);
|
|
return NULL;
|
|
}
|
|
|
|
static void io_account_cq_overflow(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rings *r = ctx->rings;
|
|
|
|
WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
|
|
ctx->cq_extra--;
|
|
}
|
|
|
|
static bool req_need_defer(struct io_kiocb *req, u32 seq)
|
|
{
|
|
if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static void io_req_track_inflight(struct io_kiocb *req)
|
|
{
|
|
if (!(req->flags & REQ_F_INFLIGHT)) {
|
|
req->flags |= REQ_F_INFLIGHT;
|
|
atomic_inc(¤t->io_uring->inflight_tracked);
|
|
}
|
|
}
|
|
|
|
static void io_prep_async_work(struct io_kiocb *req)
|
|
{
|
|
const struct io_op_def *def = &io_op_defs[req->opcode];
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (!(req->flags & REQ_F_CREDS)) {
|
|
req->flags |= REQ_F_CREDS;
|
|
req->creds = get_current_cred();
|
|
}
|
|
|
|
req->work.list.next = NULL;
|
|
req->work.flags = 0;
|
|
if (req->flags & REQ_F_FORCE_ASYNC)
|
|
req->work.flags |= IO_WQ_WORK_CONCURRENT;
|
|
|
|
if (req->flags & REQ_F_ISREG) {
|
|
if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
|
|
io_wq_hash_work(&req->work, file_inode(req->file));
|
|
} else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
|
|
if (def->unbound_nonreg_file)
|
|
req->work.flags |= IO_WQ_WORK_UNBOUND;
|
|
}
|
|
|
|
switch (req->opcode) {
|
|
case IORING_OP_SPLICE:
|
|
case IORING_OP_TEE:
|
|
if (!S_ISREG(file_inode(req->splice.file_in)->i_mode))
|
|
req->work.flags |= IO_WQ_WORK_UNBOUND;
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void io_prep_async_link(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *cur;
|
|
|
|
io_for_each_link(cur, req)
|
|
io_prep_async_work(cur);
|
|
}
|
|
|
|
static void io_queue_async_work(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_kiocb *link = io_prep_linked_timeout(req);
|
|
struct io_uring_task *tctx = req->task->io_uring;
|
|
|
|
BUG_ON(!tctx);
|
|
BUG_ON(!tctx->io_wq);
|
|
|
|
/* init ->work of the whole link before punting */
|
|
io_prep_async_link(req);
|
|
trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
|
|
&req->work, req->flags);
|
|
io_wq_enqueue(tctx->io_wq, &req->work);
|
|
if (link)
|
|
io_queue_linked_timeout(link);
|
|
}
|
|
|
|
static void io_kill_timeout(struct io_kiocb *req, int status)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
struct io_timeout_data *io = req->async_data;
|
|
|
|
if (hrtimer_try_to_cancel(&io->timer) != -1) {
|
|
atomic_set(&req->ctx->cq_timeouts,
|
|
atomic_read(&req->ctx->cq_timeouts) + 1);
|
|
list_del_init(&req->timeout.list);
|
|
io_cqring_fill_event(req->ctx, req->user_data, status, 0);
|
|
io_put_req_deferred(req, 1);
|
|
}
|
|
}
|
|
|
|
static void io_queue_deferred(struct io_ring_ctx *ctx)
|
|
{
|
|
while (!list_empty(&ctx->defer_list)) {
|
|
struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
|
|
struct io_defer_entry, list);
|
|
|
|
if (req_need_defer(de->req, de->seq))
|
|
break;
|
|
list_del_init(&de->list);
|
|
io_req_task_queue(de->req);
|
|
kfree(de);
|
|
}
|
|
}
|
|
|
|
static void io_flush_timeouts(struct io_ring_ctx *ctx)
|
|
{
|
|
u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
|
|
|
|
while (!list_empty(&ctx->timeout_list)) {
|
|
u32 events_needed, events_got;
|
|
struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
|
|
struct io_kiocb, timeout.list);
|
|
|
|
if (io_is_timeout_noseq(req))
|
|
break;
|
|
|
|
/*
|
|
* Since seq can easily wrap around over time, subtract
|
|
* the last seq at which timeouts were flushed before comparing.
|
|
* Assuming not more than 2^31-1 events have happened since,
|
|
* these subtractions won't have wrapped, so we can check if
|
|
* target is in [last_seq, current_seq] by comparing the two.
|
|
*/
|
|
events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
|
|
events_got = seq - ctx->cq_last_tm_flush;
|
|
if (events_got < events_needed)
|
|
break;
|
|
|
|
list_del_init(&req->timeout.list);
|
|
io_kill_timeout(req, 0);
|
|
}
|
|
ctx->cq_last_tm_flush = seq;
|
|
}
|
|
|
|
static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
|
|
{
|
|
if (ctx->off_timeout_used)
|
|
io_flush_timeouts(ctx);
|
|
if (ctx->drain_active)
|
|
io_queue_deferred(ctx);
|
|
}
|
|
|
|
static inline void io_commit_cqring(struct io_ring_ctx *ctx)
|
|
{
|
|
if (unlikely(ctx->off_timeout_used || ctx->drain_active))
|
|
__io_commit_cqring_flush(ctx);
|
|
/* order cqe stores with ring update */
|
|
smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
|
|
}
|
|
|
|
static inline bool io_sqring_full(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rings *r = ctx->rings;
|
|
|
|
return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
|
|
}
|
|
|
|
static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
|
|
{
|
|
return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
|
|
}
|
|
|
|
static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rings *rings = ctx->rings;
|
|
unsigned tail, mask = ctx->cq_entries - 1;
|
|
|
|
/*
|
|
* writes to the cq entry need to come after reading head; the
|
|
* control dependency is enough as we're using WRITE_ONCE to
|
|
* fill the cq entry
|
|
*/
|
|
if (__io_cqring_events(ctx) == ctx->cq_entries)
|
|
return NULL;
|
|
|
|
tail = ctx->cached_cq_tail++;
|
|
return &rings->cqes[tail & mask];
|
|
}
|
|
|
|
static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
|
|
{
|
|
if (likely(!ctx->cq_ev_fd))
|
|
return false;
|
|
if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
|
|
return false;
|
|
return !ctx->eventfd_async || io_wq_current_is_worker();
|
|
}
|
|
|
|
static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
|
|
{
|
|
/* see waitqueue_active() comment */
|
|
smp_mb();
|
|
|
|
if (waitqueue_active(&ctx->cq_wait))
|
|
wake_up(&ctx->cq_wait);
|
|
if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
|
|
wake_up(&ctx->sq_data->wait);
|
|
if (io_should_trigger_evfd(ctx))
|
|
eventfd_signal(ctx->cq_ev_fd, 1);
|
|
if (waitqueue_active(&ctx->poll_wait)) {
|
|
wake_up_interruptible(&ctx->poll_wait);
|
|
kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
|
|
}
|
|
}
|
|
|
|
static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
|
|
{
|
|
/* see waitqueue_active() comment */
|
|
smp_mb();
|
|
|
|
if (ctx->flags & IORING_SETUP_SQPOLL) {
|
|
if (waitqueue_active(&ctx->cq_wait))
|
|
wake_up(&ctx->cq_wait);
|
|
}
|
|
if (io_should_trigger_evfd(ctx))
|
|
eventfd_signal(ctx->cq_ev_fd, 1);
|
|
if (waitqueue_active(&ctx->poll_wait)) {
|
|
wake_up_interruptible(&ctx->poll_wait);
|
|
kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
|
|
}
|
|
}
|
|
|
|
/* Returns true if there are no backlogged entries after the flush */
|
|
static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
|
|
{
|
|
unsigned long flags;
|
|
bool all_flushed, posted;
|
|
|
|
if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
|
|
return false;
|
|
|
|
posted = false;
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
while (!list_empty(&ctx->cq_overflow_list)) {
|
|
struct io_uring_cqe *cqe = io_get_cqe(ctx);
|
|
struct io_overflow_cqe *ocqe;
|
|
|
|
if (!cqe && !force)
|
|
break;
|
|
ocqe = list_first_entry(&ctx->cq_overflow_list,
|
|
struct io_overflow_cqe, list);
|
|
if (cqe)
|
|
memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
|
|
else
|
|
io_account_cq_overflow(ctx);
|
|
|
|
posted = true;
|
|
list_del(&ocqe->list);
|
|
kfree(ocqe);
|
|
}
|
|
|
|
all_flushed = list_empty(&ctx->cq_overflow_list);
|
|
if (all_flushed) {
|
|
clear_bit(0, &ctx->check_cq_overflow);
|
|
ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
|
|
}
|
|
|
|
if (posted)
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
if (posted)
|
|
io_cqring_ev_posted(ctx);
|
|
return all_flushed;
|
|
}
|
|
|
|
static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
|
|
{
|
|
bool ret = true;
|
|
|
|
if (test_bit(0, &ctx->check_cq_overflow)) {
|
|
/* iopoll syncs against uring_lock, not completion_lock */
|
|
if (ctx->flags & IORING_SETUP_IOPOLL)
|
|
mutex_lock(&ctx->uring_lock);
|
|
ret = __io_cqring_overflow_flush(ctx, force);
|
|
if (ctx->flags & IORING_SETUP_IOPOLL)
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Shamelessly stolen from the mm implementation of page reference checking,
|
|
* see commit f958d7b528b1 for details.
|
|
*/
|
|
#define req_ref_zero_or_close_to_overflow(req) \
|
|
((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
|
|
|
|
static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
|
|
{
|
|
return atomic_inc_not_zero(&req->refs);
|
|
}
|
|
|
|
static inline bool req_ref_sub_and_test(struct io_kiocb *req, int refs)
|
|
{
|
|
WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
|
|
return atomic_sub_and_test(refs, &req->refs);
|
|
}
|
|
|
|
static inline bool req_ref_put_and_test(struct io_kiocb *req)
|
|
{
|
|
WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
|
|
return atomic_dec_and_test(&req->refs);
|
|
}
|
|
|
|
static inline void req_ref_put(struct io_kiocb *req)
|
|
{
|
|
WARN_ON_ONCE(req_ref_put_and_test(req));
|
|
}
|
|
|
|
static inline void req_ref_get(struct io_kiocb *req)
|
|
{
|
|
WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
|
|
atomic_inc(&req->refs);
|
|
}
|
|
|
|
static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
|
|
long res, unsigned int cflags)
|
|
{
|
|
struct io_overflow_cqe *ocqe;
|
|
|
|
ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
|
|
if (!ocqe) {
|
|
/*
|
|
* If we're in ring overflow flush mode, or in task cancel mode,
|
|
* or cannot allocate an overflow entry, then we need to drop it
|
|
* on the floor.
|
|
*/
|
|
io_account_cq_overflow(ctx);
|
|
return false;
|
|
}
|
|
if (list_empty(&ctx->cq_overflow_list)) {
|
|
set_bit(0, &ctx->check_cq_overflow);
|
|
ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW;
|
|
}
|
|
ocqe->cqe.user_data = user_data;
|
|
ocqe->cqe.res = res;
|
|
ocqe->cqe.flags = cflags;
|
|
list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
|
|
return true;
|
|
}
|
|
|
|
static inline bool __io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
|
|
long res, unsigned int cflags)
|
|
{
|
|
struct io_uring_cqe *cqe;
|
|
|
|
trace_io_uring_complete(ctx, user_data, res, cflags);
|
|
|
|
/*
|
|
* If we can't get a cq entry, userspace overflowed the
|
|
* submission (by quite a lot). Increment the overflow count in
|
|
* the ring.
|
|
*/
|
|
cqe = io_get_cqe(ctx);
|
|
if (likely(cqe)) {
|
|
WRITE_ONCE(cqe->user_data, user_data);
|
|
WRITE_ONCE(cqe->res, res);
|
|
WRITE_ONCE(cqe->flags, cflags);
|
|
return true;
|
|
}
|
|
return io_cqring_event_overflow(ctx, user_data, res, cflags);
|
|
}
|
|
|
|
/* not as hot to bloat with inlining */
|
|
static noinline bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
|
|
long res, unsigned int cflags)
|
|
{
|
|
return __io_cqring_fill_event(ctx, user_data, res, cflags);
|
|
}
|
|
|
|
static void io_req_complete_post(struct io_kiocb *req, long res,
|
|
unsigned int cflags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
__io_cqring_fill_event(ctx, req->user_data, res, cflags);
|
|
/*
|
|
* If we're the last reference to this request, add to our locked
|
|
* free_list cache.
|
|
*/
|
|
if (req_ref_put_and_test(req)) {
|
|
if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
|
|
if (req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_FAIL))
|
|
io_disarm_next(req);
|
|
if (req->link) {
|
|
io_req_task_queue(req->link);
|
|
req->link = NULL;
|
|
}
|
|
}
|
|
io_dismantle_req(req);
|
|
io_put_task(req->task, 1);
|
|
list_add(&req->compl.list, &ctx->locked_free_list);
|
|
ctx->locked_free_nr++;
|
|
} else {
|
|
if (!percpu_ref_tryget(&ctx->refs))
|
|
req = NULL;
|
|
}
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
|
|
if (req) {
|
|
io_cqring_ev_posted(ctx);
|
|
percpu_ref_put(&ctx->refs);
|
|
}
|
|
}
|
|
|
|
static inline bool io_req_needs_clean(struct io_kiocb *req)
|
|
{
|
|
return req->flags & IO_REQ_CLEAN_FLAGS;
|
|
}
|
|
|
|
static void io_req_complete_state(struct io_kiocb *req, long res,
|
|
unsigned int cflags)
|
|
{
|
|
if (io_req_needs_clean(req))
|
|
io_clean_op(req);
|
|
req->result = res;
|
|
req->compl.cflags = cflags;
|
|
req->flags |= REQ_F_COMPLETE_INLINE;
|
|
}
|
|
|
|
static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
|
|
long res, unsigned cflags)
|
|
{
|
|
if (issue_flags & IO_URING_F_COMPLETE_DEFER)
|
|
io_req_complete_state(req, res, cflags);
|
|
else
|
|
io_req_complete_post(req, res, cflags);
|
|
}
|
|
|
|
static inline void io_req_complete(struct io_kiocb *req, long res)
|
|
{
|
|
__io_req_complete(req, 0, res, 0);
|
|
}
|
|
|
|
static void io_req_complete_failed(struct io_kiocb *req, long res)
|
|
{
|
|
req_set_fail(req);
|
|
io_put_req(req);
|
|
io_req_complete_post(req, res, 0);
|
|
}
|
|
|
|
static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
|
|
struct io_comp_state *cs)
|
|
{
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
list_splice_init(&ctx->locked_free_list, &cs->free_list);
|
|
ctx->locked_free_nr = 0;
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
}
|
|
|
|
/* Returns true IFF there are requests in the cache */
|
|
static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_submit_state *state = &ctx->submit_state;
|
|
struct io_comp_state *cs = &state->comp;
|
|
int nr;
|
|
|
|
/*
|
|
* If we have more than a batch's worth of requests in our IRQ side
|
|
* locked cache, grab the lock and move them over to our submission
|
|
* side cache.
|
|
*/
|
|
if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
|
|
io_flush_cached_locked_reqs(ctx, cs);
|
|
|
|
nr = state->free_reqs;
|
|
while (!list_empty(&cs->free_list)) {
|
|
struct io_kiocb *req = list_first_entry(&cs->free_list,
|
|
struct io_kiocb, compl.list);
|
|
|
|
list_del(&req->compl.list);
|
|
state->reqs[nr++] = req;
|
|
if (nr == ARRAY_SIZE(state->reqs))
|
|
break;
|
|
}
|
|
|
|
state->free_reqs = nr;
|
|
return nr != 0;
|
|
}
|
|
|
|
static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_submit_state *state = &ctx->submit_state;
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH);
|
|
|
|
if (!state->free_reqs) {
|
|
gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
|
|
int ret, i;
|
|
|
|
if (io_flush_cached_reqs(ctx))
|
|
goto got_req;
|
|
|
|
ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
|
|
state->reqs);
|
|
|
|
/*
|
|
* Bulk alloc is all-or-nothing. If we fail to get a batch,
|
|
* retry single alloc to be on the safe side.
|
|
*/
|
|
if (unlikely(ret <= 0)) {
|
|
state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
|
|
if (!state->reqs[0])
|
|
return NULL;
|
|
ret = 1;
|
|
}
|
|
|
|
/*
|
|
* Don't initialise the fields below on every allocation, but
|
|
* do that in advance and keep valid on free.
|
|
*/
|
|
for (i = 0; i < ret; i++) {
|
|
struct io_kiocb *req = state->reqs[i];
|
|
|
|
req->ctx = ctx;
|
|
req->link = NULL;
|
|
req->async_data = NULL;
|
|
/* not necessary, but safer to zero */
|
|
req->result = 0;
|
|
}
|
|
state->free_reqs = ret;
|
|
}
|
|
got_req:
|
|
state->free_reqs--;
|
|
return state->reqs[state->free_reqs];
|
|
}
|
|
|
|
static inline void io_put_file(struct file *file)
|
|
{
|
|
if (file)
|
|
fput(file);
|
|
}
|
|
|
|
static void io_dismantle_req(struct io_kiocb *req)
|
|
{
|
|
unsigned int flags = req->flags;
|
|
|
|
if (io_req_needs_clean(req))
|
|
io_clean_op(req);
|
|
if (!(flags & REQ_F_FIXED_FILE))
|
|
io_put_file(req->file);
|
|
if (req->fixed_rsrc_refs)
|
|
percpu_ref_put(req->fixed_rsrc_refs);
|
|
if (req->async_data) {
|
|
kfree(req->async_data);
|
|
req->async_data = NULL;
|
|
}
|
|
}
|
|
|
|
/* must to be called somewhat shortly after putting a request */
|
|
static inline void io_put_task(struct task_struct *task, int nr)
|
|
{
|
|
struct io_uring_task *tctx = task->io_uring;
|
|
|
|
percpu_counter_sub(&tctx->inflight, nr);
|
|
if (unlikely(atomic_read(&tctx->in_idle)))
|
|
wake_up(&tctx->wait);
|
|
put_task_struct_many(task, nr);
|
|
}
|
|
|
|
static void __io_free_req(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
io_dismantle_req(req);
|
|
io_put_task(req->task, 1);
|
|
|
|
kmem_cache_free(req_cachep, req);
|
|
percpu_ref_put(&ctx->refs);
|
|
}
|
|
|
|
static inline void io_remove_next_linked(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *nxt = req->link;
|
|
|
|
req->link = nxt->link;
|
|
nxt->link = NULL;
|
|
}
|
|
|
|
static bool io_kill_linked_timeout(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
struct io_kiocb *link = req->link;
|
|
|
|
/*
|
|
* Can happen if a linked timeout fired and link had been like
|
|
* req -> link t-out -> link t-out [-> ...]
|
|
*/
|
|
if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
|
|
struct io_timeout_data *io = link->async_data;
|
|
|
|
io_remove_next_linked(req);
|
|
link->timeout.head = NULL;
|
|
if (hrtimer_try_to_cancel(&io->timer) != -1) {
|
|
io_cqring_fill_event(link->ctx, link->user_data,
|
|
-ECANCELED, 0);
|
|
io_put_req_deferred(link, 1);
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static void io_fail_links(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
struct io_kiocb *nxt, *link = req->link;
|
|
|
|
req->link = NULL;
|
|
while (link) {
|
|
nxt = link->link;
|
|
link->link = NULL;
|
|
|
|
trace_io_uring_fail_link(req, link);
|
|
io_cqring_fill_event(link->ctx, link->user_data, -ECANCELED, 0);
|
|
io_put_req_deferred(link, 2);
|
|
link = nxt;
|
|
}
|
|
}
|
|
|
|
static bool io_disarm_next(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
bool posted = false;
|
|
|
|
if (likely(req->flags & REQ_F_LINK_TIMEOUT))
|
|
posted = io_kill_linked_timeout(req);
|
|
if (unlikely((req->flags & REQ_F_FAIL) &&
|
|
!(req->flags & REQ_F_HARDLINK))) {
|
|
posted |= (req->link != NULL);
|
|
io_fail_links(req);
|
|
}
|
|
return posted;
|
|
}
|
|
|
|
static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *nxt;
|
|
|
|
/*
|
|
* If LINK is set, we have dependent requests in this chain. If we
|
|
* didn't fail this request, queue the first one up, moving any other
|
|
* dependencies to the next request. In case of failure, fail the rest
|
|
* of the chain.
|
|
*/
|
|
if (req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_FAIL)) {
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
unsigned long flags;
|
|
bool posted;
|
|
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
posted = io_disarm_next(req);
|
|
if (posted)
|
|
io_commit_cqring(req->ctx);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
if (posted)
|
|
io_cqring_ev_posted(ctx);
|
|
}
|
|
nxt = req->link;
|
|
req->link = NULL;
|
|
return nxt;
|
|
}
|
|
|
|
static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
|
|
{
|
|
if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
|
|
return NULL;
|
|
return __io_req_find_next(req);
|
|
}
|
|
|
|
static void ctx_flush_and_put(struct io_ring_ctx *ctx)
|
|
{
|
|
if (!ctx)
|
|
return;
|
|
if (ctx->submit_state.comp.nr) {
|
|
mutex_lock(&ctx->uring_lock);
|
|
io_submit_flush_completions(ctx);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
percpu_ref_put(&ctx->refs);
|
|
}
|
|
|
|
static void tctx_task_work(struct callback_head *cb)
|
|
{
|
|
struct io_ring_ctx *ctx = NULL;
|
|
struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
|
|
task_work);
|
|
|
|
while (1) {
|
|
struct io_wq_work_node *node;
|
|
|
|
spin_lock_irq(&tctx->task_lock);
|
|
node = tctx->task_list.first;
|
|
INIT_WQ_LIST(&tctx->task_list);
|
|
spin_unlock_irq(&tctx->task_lock);
|
|
|
|
while (node) {
|
|
struct io_wq_work_node *next = node->next;
|
|
struct io_kiocb *req = container_of(node, struct io_kiocb,
|
|
io_task_work.node);
|
|
|
|
if (req->ctx != ctx) {
|
|
ctx_flush_and_put(ctx);
|
|
ctx = req->ctx;
|
|
percpu_ref_get(&ctx->refs);
|
|
}
|
|
req->io_task_work.func(req);
|
|
node = next;
|
|
}
|
|
if (wq_list_empty(&tctx->task_list)) {
|
|
clear_bit(0, &tctx->task_state);
|
|
if (wq_list_empty(&tctx->task_list))
|
|
break;
|
|
/* another tctx_task_work() is enqueued, yield */
|
|
if (test_and_set_bit(0, &tctx->task_state))
|
|
break;
|
|
}
|
|
cond_resched();
|
|
}
|
|
|
|
ctx_flush_and_put(ctx);
|
|
}
|
|
|
|
static void io_req_task_work_add(struct io_kiocb *req)
|
|
{
|
|
struct task_struct *tsk = req->task;
|
|
struct io_uring_task *tctx = tsk->io_uring;
|
|
enum task_work_notify_mode notify;
|
|
struct io_wq_work_node *node;
|
|
unsigned long flags;
|
|
|
|
WARN_ON_ONCE(!tctx);
|
|
|
|
spin_lock_irqsave(&tctx->task_lock, flags);
|
|
wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
|
|
spin_unlock_irqrestore(&tctx->task_lock, flags);
|
|
|
|
/* task_work already pending, we're done */
|
|
if (test_bit(0, &tctx->task_state) ||
|
|
test_and_set_bit(0, &tctx->task_state))
|
|
return;
|
|
if (unlikely(tsk->flags & PF_EXITING))
|
|
goto fail;
|
|
|
|
/*
|
|
* SQPOLL kernel thread doesn't need notification, just a wakeup. For
|
|
* all other cases, use TWA_SIGNAL unconditionally to ensure we're
|
|
* processing task_work. There's no reliable way to tell if TWA_RESUME
|
|
* will do the job.
|
|
*/
|
|
notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
|
|
if (!task_work_add(tsk, &tctx->task_work, notify)) {
|
|
wake_up_process(tsk);
|
|
return;
|
|
}
|
|
fail:
|
|
clear_bit(0, &tctx->task_state);
|
|
spin_lock_irqsave(&tctx->task_lock, flags);
|
|
node = tctx->task_list.first;
|
|
INIT_WQ_LIST(&tctx->task_list);
|
|
spin_unlock_irqrestore(&tctx->task_lock, flags);
|
|
|
|
while (node) {
|
|
req = container_of(node, struct io_kiocb, io_task_work.node);
|
|
node = node->next;
|
|
if (llist_add(&req->io_task_work.fallback_node,
|
|
&req->ctx->fallback_llist))
|
|
schedule_delayed_work(&req->ctx->fallback_work, 1);
|
|
}
|
|
}
|
|
|
|
static void io_req_task_cancel(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
/* ctx is guaranteed to stay alive while we hold uring_lock */
|
|
mutex_lock(&ctx->uring_lock);
|
|
io_req_complete_failed(req, req->result);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static void io_req_task_submit(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
/* ctx stays valid until unlock, even if we drop all ours ctx->refs */
|
|
mutex_lock(&ctx->uring_lock);
|
|
if (!(current->flags & PF_EXITING) && !current->in_execve)
|
|
__io_queue_sqe(req);
|
|
else
|
|
io_req_complete_failed(req, -EFAULT);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
|
|
{
|
|
req->result = ret;
|
|
req->io_task_work.func = io_req_task_cancel;
|
|
io_req_task_work_add(req);
|
|
}
|
|
|
|
static void io_req_task_queue(struct io_kiocb *req)
|
|
{
|
|
req->io_task_work.func = io_req_task_submit;
|
|
io_req_task_work_add(req);
|
|
}
|
|
|
|
static inline void io_queue_next(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *nxt = io_req_find_next(req);
|
|
|
|
if (nxt)
|
|
io_req_task_queue(nxt);
|
|
}
|
|
|
|
static void io_free_req(struct io_kiocb *req)
|
|
{
|
|
io_queue_next(req);
|
|
__io_free_req(req);
|
|
}
|
|
|
|
struct req_batch {
|
|
struct task_struct *task;
|
|
int task_refs;
|
|
int ctx_refs;
|
|
};
|
|
|
|
static inline void io_init_req_batch(struct req_batch *rb)
|
|
{
|
|
rb->task_refs = 0;
|
|
rb->ctx_refs = 0;
|
|
rb->task = NULL;
|
|
}
|
|
|
|
static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
|
|
struct req_batch *rb)
|
|
{
|
|
if (rb->task)
|
|
io_put_task(rb->task, rb->task_refs);
|
|
if (rb->ctx_refs)
|
|
percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
|
|
}
|
|
|
|
static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
|
|
struct io_submit_state *state)
|
|
{
|
|
io_queue_next(req);
|
|
io_dismantle_req(req);
|
|
|
|
if (req->task != rb->task) {
|
|
if (rb->task)
|
|
io_put_task(rb->task, rb->task_refs);
|
|
rb->task = req->task;
|
|
rb->task_refs = 0;
|
|
}
|
|
rb->task_refs++;
|
|
rb->ctx_refs++;
|
|
|
|
if (state->free_reqs != ARRAY_SIZE(state->reqs))
|
|
state->reqs[state->free_reqs++] = req;
|
|
else
|
|
list_add(&req->compl.list, &state->comp.free_list);
|
|
}
|
|
|
|
static void io_submit_flush_completions(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_comp_state *cs = &ctx->submit_state.comp;
|
|
int i, nr = cs->nr;
|
|
struct req_batch rb;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
for (i = 0; i < nr; i++) {
|
|
struct io_kiocb *req = cs->reqs[i];
|
|
|
|
__io_cqring_fill_event(ctx, req->user_data, req->result,
|
|
req->compl.cflags);
|
|
}
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
io_cqring_ev_posted(ctx);
|
|
|
|
io_init_req_batch(&rb);
|
|
for (i = 0; i < nr; i++) {
|
|
struct io_kiocb *req = cs->reqs[i];
|
|
|
|
/* submission and completion refs */
|
|
if (req_ref_sub_and_test(req, 2))
|
|
io_req_free_batch(&rb, req, &ctx->submit_state);
|
|
}
|
|
|
|
io_req_free_batch_finish(ctx, &rb);
|
|
cs->nr = 0;
|
|
}
|
|
|
|
/*
|
|
* Drop reference to request, return next in chain (if there is one) if this
|
|
* was the last reference to this request.
|
|
*/
|
|
static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *nxt = NULL;
|
|
|
|
if (req_ref_put_and_test(req)) {
|
|
nxt = io_req_find_next(req);
|
|
__io_free_req(req);
|
|
}
|
|
return nxt;
|
|
}
|
|
|
|
static inline void io_put_req(struct io_kiocb *req)
|
|
{
|
|
if (req_ref_put_and_test(req))
|
|
io_free_req(req);
|
|
}
|
|
|
|
static void io_free_req_deferred(struct io_kiocb *req)
|
|
{
|
|
req->io_task_work.func = io_free_req;
|
|
io_req_task_work_add(req);
|
|
}
|
|
|
|
static inline void io_put_req_deferred(struct io_kiocb *req, int refs)
|
|
{
|
|
if (req_ref_sub_and_test(req, refs))
|
|
io_free_req_deferred(req);
|
|
}
|
|
|
|
static unsigned io_cqring_events(struct io_ring_ctx *ctx)
|
|
{
|
|
/* See comment at the top of this file */
|
|
smp_rmb();
|
|
return __io_cqring_events(ctx);
|
|
}
|
|
|
|
static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rings *rings = ctx->rings;
|
|
|
|
/* make sure SQ entry isn't read before tail */
|
|
return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
|
|
}
|
|
|
|
static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
|
|
{
|
|
unsigned int cflags;
|
|
|
|
cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
|
|
cflags |= IORING_CQE_F_BUFFER;
|
|
req->flags &= ~REQ_F_BUFFER_SELECTED;
|
|
kfree(kbuf);
|
|
return cflags;
|
|
}
|
|
|
|
static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
|
|
{
|
|
struct io_buffer *kbuf;
|
|
|
|
kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
|
|
return io_put_kbuf(req, kbuf);
|
|
}
|
|
|
|
static inline bool io_run_task_work(void)
|
|
{
|
|
if (current->task_works) {
|
|
__set_current_state(TASK_RUNNING);
|
|
task_work_run();
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Find and free completed poll iocbs
|
|
*/
|
|
static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
|
|
struct list_head *done)
|
|
{
|
|
struct req_batch rb;
|
|
struct io_kiocb *req;
|
|
|
|
/* order with ->result store in io_complete_rw_iopoll() */
|
|
smp_rmb();
|
|
|
|
io_init_req_batch(&rb);
|
|
while (!list_empty(done)) {
|
|
int cflags = 0;
|
|
|
|
req = list_first_entry(done, struct io_kiocb, inflight_entry);
|
|
list_del(&req->inflight_entry);
|
|
|
|
if (READ_ONCE(req->result) == -EAGAIN &&
|
|
!(req->flags & REQ_F_DONT_REISSUE)) {
|
|
req->iopoll_completed = 0;
|
|
req_ref_get(req);
|
|
io_queue_async_work(req);
|
|
continue;
|
|
}
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
cflags = io_put_rw_kbuf(req);
|
|
|
|
__io_cqring_fill_event(ctx, req->user_data, req->result, cflags);
|
|
(*nr_events)++;
|
|
|
|
if (req_ref_put_and_test(req))
|
|
io_req_free_batch(&rb, req, &ctx->submit_state);
|
|
}
|
|
|
|
io_commit_cqring(ctx);
|
|
io_cqring_ev_posted_iopoll(ctx);
|
|
io_req_free_batch_finish(ctx, &rb);
|
|
}
|
|
|
|
static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
|
|
long min)
|
|
{
|
|
struct io_kiocb *req, *tmp;
|
|
LIST_HEAD(done);
|
|
bool spin;
|
|
int ret;
|
|
|
|
/*
|
|
* Only spin for completions if we don't have multiple devices hanging
|
|
* off our complete list, and we're under the requested amount.
|
|
*/
|
|
spin = !ctx->poll_multi_queue && *nr_events < min;
|
|
|
|
ret = 0;
|
|
list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
|
|
/*
|
|
* Move completed and retryable entries to our local lists.
|
|
* If we find a request that requires polling, break out
|
|
* and complete those lists first, if we have entries there.
|
|
*/
|
|
if (READ_ONCE(req->iopoll_completed)) {
|
|
list_move_tail(&req->inflight_entry, &done);
|
|
continue;
|
|
}
|
|
if (!list_empty(&done))
|
|
break;
|
|
|
|
ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
|
|
if (ret < 0)
|
|
break;
|
|
|
|
/* iopoll may have completed current req */
|
|
if (READ_ONCE(req->iopoll_completed))
|
|
list_move_tail(&req->inflight_entry, &done);
|
|
|
|
if (ret && spin)
|
|
spin = false;
|
|
ret = 0;
|
|
}
|
|
|
|
if (!list_empty(&done))
|
|
io_iopoll_complete(ctx, nr_events, &done);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* We can't just wait for polled events to come to us, we have to actively
|
|
* find and complete them.
|
|
*/
|
|
static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
|
|
{
|
|
if (!(ctx->flags & IORING_SETUP_IOPOLL))
|
|
return;
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
while (!list_empty(&ctx->iopoll_list)) {
|
|
unsigned int nr_events = 0;
|
|
|
|
io_do_iopoll(ctx, &nr_events, 0);
|
|
|
|
/* let it sleep and repeat later if can't complete a request */
|
|
if (nr_events == 0)
|
|
break;
|
|
/*
|
|
* Ensure we allow local-to-the-cpu processing to take place,
|
|
* in this case we need to ensure that we reap all events.
|
|
* Also let task_work, etc. to progress by releasing the mutex
|
|
*/
|
|
if (need_resched()) {
|
|
mutex_unlock(&ctx->uring_lock);
|
|
cond_resched();
|
|
mutex_lock(&ctx->uring_lock);
|
|
}
|
|
}
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
|
|
{
|
|
unsigned int nr_events = 0;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* We disallow the app entering submit/complete with polling, but we
|
|
* still need to lock the ring to prevent racing with polled issue
|
|
* that got punted to a workqueue.
|
|
*/
|
|
mutex_lock(&ctx->uring_lock);
|
|
/*
|
|
* Don't enter poll loop if we already have events pending.
|
|
* If we do, we can potentially be spinning for commands that
|
|
* already triggered a CQE (eg in error).
|
|
*/
|
|
if (test_bit(0, &ctx->check_cq_overflow))
|
|
__io_cqring_overflow_flush(ctx, false);
|
|
if (io_cqring_events(ctx))
|
|
goto out;
|
|
do {
|
|
/*
|
|
* If a submit got punted to a workqueue, we can have the
|
|
* application entering polling for a command before it gets
|
|
* issued. That app will hold the uring_lock for the duration
|
|
* of the poll right here, so we need to take a breather every
|
|
* now and then to ensure that the issue has a chance to add
|
|
* the poll to the issued list. Otherwise we can spin here
|
|
* forever, while the workqueue is stuck trying to acquire the
|
|
* very same mutex.
|
|
*/
|
|
if (list_empty(&ctx->iopoll_list)) {
|
|
u32 tail = ctx->cached_cq_tail;
|
|
|
|
mutex_unlock(&ctx->uring_lock);
|
|
io_run_task_work();
|
|
mutex_lock(&ctx->uring_lock);
|
|
|
|
/* some requests don't go through iopoll_list */
|
|
if (tail != ctx->cached_cq_tail ||
|
|
list_empty(&ctx->iopoll_list))
|
|
break;
|
|
}
|
|
ret = io_do_iopoll(ctx, &nr_events, min);
|
|
} while (!ret && nr_events < min && !need_resched());
|
|
out:
|
|
mutex_unlock(&ctx->uring_lock);
|
|
return ret;
|
|
}
|
|
|
|
static void kiocb_end_write(struct io_kiocb *req)
|
|
{
|
|
/*
|
|
* Tell lockdep we inherited freeze protection from submission
|
|
* thread.
|
|
*/
|
|
if (req->flags & REQ_F_ISREG) {
|
|
struct super_block *sb = file_inode(req->file)->i_sb;
|
|
|
|
__sb_writers_acquired(sb, SB_FREEZE_WRITE);
|
|
sb_end_write(sb);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
static bool io_resubmit_prep(struct io_kiocb *req)
|
|
{
|
|
struct io_async_rw *rw = req->async_data;
|
|
|
|
if (!rw)
|
|
return !io_req_prep_async(req);
|
|
/* may have left rw->iter inconsistent on -EIOCBQUEUED */
|
|
iov_iter_revert(&rw->iter, req->result - iov_iter_count(&rw->iter));
|
|
return true;
|
|
}
|
|
|
|
static bool io_rw_should_reissue(struct io_kiocb *req)
|
|
{
|
|
umode_t mode = file_inode(req->file)->i_mode;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (!S_ISBLK(mode) && !S_ISREG(mode))
|
|
return false;
|
|
if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
|
|
!(ctx->flags & IORING_SETUP_IOPOLL)))
|
|
return false;
|
|
/*
|
|
* If ref is dying, we might be running poll reap from the exit work.
|
|
* Don't attempt to reissue from that path, just let it fail with
|
|
* -EAGAIN.
|
|
*/
|
|
if (percpu_ref_is_dying(&ctx->refs))
|
|
return false;
|
|
return true;
|
|
}
|
|
#else
|
|
static bool io_resubmit_prep(struct io_kiocb *req)
|
|
{
|
|
return false;
|
|
}
|
|
static bool io_rw_should_reissue(struct io_kiocb *req)
|
|
{
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
static void io_fallback_req_func(struct work_struct *work)
|
|
{
|
|
struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
|
|
fallback_work.work);
|
|
struct llist_node *node = llist_del_all(&ctx->fallback_llist);
|
|
struct io_kiocb *req, *tmp;
|
|
|
|
llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
|
|
req->io_task_work.func(req);
|
|
}
|
|
|
|
static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
|
|
unsigned int issue_flags)
|
|
{
|
|
int cflags = 0;
|
|
|
|
if (req->rw.kiocb.ki_flags & IOCB_WRITE)
|
|
kiocb_end_write(req);
|
|
if (res != req->result) {
|
|
if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
|
|
io_rw_should_reissue(req)) {
|
|
req->flags |= REQ_F_REISSUE;
|
|
return;
|
|
}
|
|
req_set_fail(req);
|
|
}
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
cflags = io_put_rw_kbuf(req);
|
|
__io_req_complete(req, issue_flags, res, cflags);
|
|
}
|
|
|
|
static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
|
|
{
|
|
struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
|
|
|
|
__io_complete_rw(req, res, res2, 0);
|
|
}
|
|
|
|
static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
|
|
{
|
|
struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
|
|
|
|
if (kiocb->ki_flags & IOCB_WRITE)
|
|
kiocb_end_write(req);
|
|
if (unlikely(res != req->result)) {
|
|
if (!(res == -EAGAIN && io_rw_should_reissue(req) &&
|
|
io_resubmit_prep(req))) {
|
|
req_set_fail(req);
|
|
req->flags |= REQ_F_DONT_REISSUE;
|
|
}
|
|
}
|
|
|
|
WRITE_ONCE(req->result, res);
|
|
/* order with io_iopoll_complete() checking ->result */
|
|
smp_wmb();
|
|
WRITE_ONCE(req->iopoll_completed, 1);
|
|
}
|
|
|
|
/*
|
|
* After the iocb has been issued, it's safe to be found on the poll list.
|
|
* Adding the kiocb to the list AFTER submission ensures that we don't
|
|
* find it from a io_do_iopoll() thread before the issuer is done
|
|
* accessing the kiocb cookie.
|
|
*/
|
|
static void io_iopoll_req_issued(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
const bool in_async = io_wq_current_is_worker();
|
|
|
|
/* workqueue context doesn't hold uring_lock, grab it now */
|
|
if (unlikely(in_async))
|
|
mutex_lock(&ctx->uring_lock);
|
|
|
|
/*
|
|
* Track whether we have multiple files in our lists. This will impact
|
|
* how we do polling eventually, not spinning if we're on potentially
|
|
* different devices.
|
|
*/
|
|
if (list_empty(&ctx->iopoll_list)) {
|
|
ctx->poll_multi_queue = false;
|
|
} else if (!ctx->poll_multi_queue) {
|
|
struct io_kiocb *list_req;
|
|
unsigned int queue_num0, queue_num1;
|
|
|
|
list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
|
|
inflight_entry);
|
|
|
|
if (list_req->file != req->file) {
|
|
ctx->poll_multi_queue = true;
|
|
} else {
|
|
queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie);
|
|
queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie);
|
|
if (queue_num0 != queue_num1)
|
|
ctx->poll_multi_queue = true;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* For fast devices, IO may have already completed. If it has, add
|
|
* it to the front so we find it first.
|
|
*/
|
|
if (READ_ONCE(req->iopoll_completed))
|
|
list_add(&req->inflight_entry, &ctx->iopoll_list);
|
|
else
|
|
list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
|
|
|
|
if (unlikely(in_async)) {
|
|
/*
|
|
* If IORING_SETUP_SQPOLL is enabled, sqes are either handle
|
|
* in sq thread task context or in io worker task context. If
|
|
* current task context is sq thread, we don't need to check
|
|
* whether should wake up sq thread.
|
|
*/
|
|
if ((ctx->flags & IORING_SETUP_SQPOLL) &&
|
|
wq_has_sleeper(&ctx->sq_data->wait))
|
|
wake_up(&ctx->sq_data->wait);
|
|
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
}
|
|
|
|
static inline void io_state_file_put(struct io_submit_state *state)
|
|
{
|
|
if (state->file_refs) {
|
|
fput_many(state->file, state->file_refs);
|
|
state->file_refs = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Get as many references to a file as we have IOs left in this submission,
|
|
* assuming most submissions are for one file, or at least that each file
|
|
* has more than one submission.
|
|
*/
|
|
static struct file *__io_file_get(struct io_submit_state *state, int fd)
|
|
{
|
|
if (!state)
|
|
return fget(fd);
|
|
|
|
if (state->file_refs) {
|
|
if (state->fd == fd) {
|
|
state->file_refs--;
|
|
return state->file;
|
|
}
|
|
io_state_file_put(state);
|
|
}
|
|
state->file = fget_many(fd, state->ios_left);
|
|
if (unlikely(!state->file))
|
|
return NULL;
|
|
|
|
state->fd = fd;
|
|
state->file_refs = state->ios_left - 1;
|
|
return state->file;
|
|
}
|
|
|
|
static bool io_bdev_nowait(struct block_device *bdev)
|
|
{
|
|
return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
|
|
}
|
|
|
|
/*
|
|
* If we tracked the file through the SCM inflight mechanism, we could support
|
|
* any file. For now, just ensure that anything potentially problematic is done
|
|
* inline.
|
|
*/
|
|
static bool __io_file_supports_async(struct file *file, int rw)
|
|
{
|
|
umode_t mode = file_inode(file)->i_mode;
|
|
|
|
if (S_ISBLK(mode)) {
|
|
if (IS_ENABLED(CONFIG_BLOCK) &&
|
|
io_bdev_nowait(I_BDEV(file->f_mapping->host)))
|
|
return true;
|
|
return false;
|
|
}
|
|
if (S_ISSOCK(mode))
|
|
return true;
|
|
if (S_ISREG(mode)) {
|
|
if (IS_ENABLED(CONFIG_BLOCK) &&
|
|
io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
|
|
file->f_op != &io_uring_fops)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/* any ->read/write should understand O_NONBLOCK */
|
|
if (file->f_flags & O_NONBLOCK)
|
|
return true;
|
|
|
|
if (!(file->f_mode & FMODE_NOWAIT))
|
|
return false;
|
|
|
|
if (rw == READ)
|
|
return file->f_op->read_iter != NULL;
|
|
|
|
return file->f_op->write_iter != NULL;
|
|
}
|
|
|
|
static bool io_file_supports_async(struct io_kiocb *req, int rw)
|
|
{
|
|
if (rw == READ && (req->flags & REQ_F_ASYNC_READ))
|
|
return true;
|
|
else if (rw == WRITE && (req->flags & REQ_F_ASYNC_WRITE))
|
|
return true;
|
|
|
|
return __io_file_supports_async(req->file, rw);
|
|
}
|
|
|
|
static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
struct file *file = req->file;
|
|
unsigned ioprio;
|
|
int ret;
|
|
|
|
if (!(req->flags & REQ_F_ISREG) && S_ISREG(file_inode(file)->i_mode))
|
|
req->flags |= REQ_F_ISREG;
|
|
|
|
kiocb->ki_pos = READ_ONCE(sqe->off);
|
|
if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {
|
|
req->flags |= REQ_F_CUR_POS;
|
|
kiocb->ki_pos = file->f_pos;
|
|
}
|
|
kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
|
|
kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
|
|
ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
|
|
if (unlikely(ret))
|
|
return ret;
|
|
|
|
/* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
|
|
if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))
|
|
req->flags |= REQ_F_NOWAIT;
|
|
|
|
ioprio = READ_ONCE(sqe->ioprio);
|
|
if (ioprio) {
|
|
ret = ioprio_check_cap(ioprio);
|
|
if (ret)
|
|
return ret;
|
|
|
|
kiocb->ki_ioprio = ioprio;
|
|
} else
|
|
kiocb->ki_ioprio = get_current_ioprio();
|
|
|
|
if (ctx->flags & IORING_SETUP_IOPOLL) {
|
|
if (!(kiocb->ki_flags & IOCB_DIRECT) ||
|
|
!kiocb->ki_filp->f_op->iopoll)
|
|
return -EOPNOTSUPP;
|
|
|
|
kiocb->ki_flags |= IOCB_HIPRI;
|
|
kiocb->ki_complete = io_complete_rw_iopoll;
|
|
req->iopoll_completed = 0;
|
|
} else {
|
|
if (kiocb->ki_flags & IOCB_HIPRI)
|
|
return -EINVAL;
|
|
kiocb->ki_complete = io_complete_rw;
|
|
}
|
|
|
|
if (req->opcode == IORING_OP_READ_FIXED ||
|
|
req->opcode == IORING_OP_WRITE_FIXED) {
|
|
req->imu = NULL;
|
|
io_req_set_rsrc_node(req);
|
|
}
|
|
|
|
req->rw.addr = READ_ONCE(sqe->addr);
|
|
req->rw.len = READ_ONCE(sqe->len);
|
|
req->buf_index = READ_ONCE(sqe->buf_index);
|
|
return 0;
|
|
}
|
|
|
|
static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
|
|
{
|
|
switch (ret) {
|
|
case -EIOCBQUEUED:
|
|
break;
|
|
case -ERESTARTSYS:
|
|
case -ERESTARTNOINTR:
|
|
case -ERESTARTNOHAND:
|
|
case -ERESTART_RESTARTBLOCK:
|
|
/*
|
|
* We can't just restart the syscall, since previously
|
|
* submitted sqes may already be in progress. Just fail this
|
|
* IO with EINTR.
|
|
*/
|
|
ret = -EINTR;
|
|
fallthrough;
|
|
default:
|
|
kiocb->ki_complete(kiocb, ret, 0);
|
|
}
|
|
}
|
|
|
|
static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
|
|
unsigned int issue_flags)
|
|
{
|
|
struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
|
|
struct io_async_rw *io = req->async_data;
|
|
bool check_reissue = kiocb->ki_complete == io_complete_rw;
|
|
|
|
/* add previously done IO, if any */
|
|
if (io && io->bytes_done > 0) {
|
|
if (ret < 0)
|
|
ret = io->bytes_done;
|
|
else
|
|
ret += io->bytes_done;
|
|
}
|
|
|
|
if (req->flags & REQ_F_CUR_POS)
|
|
req->file->f_pos = kiocb->ki_pos;
|
|
if (ret >= 0 && check_reissue)
|
|
__io_complete_rw(req, ret, 0, issue_flags);
|
|
else
|
|
io_rw_done(kiocb, ret);
|
|
|
|
if (check_reissue && (req->flags & REQ_F_REISSUE)) {
|
|
req->flags &= ~REQ_F_REISSUE;
|
|
if (io_resubmit_prep(req)) {
|
|
req_ref_get(req);
|
|
io_queue_async_work(req);
|
|
} else {
|
|
int cflags = 0;
|
|
|
|
req_set_fail(req);
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
cflags = io_put_rw_kbuf(req);
|
|
__io_req_complete(req, issue_flags, ret, cflags);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
|
|
struct io_mapped_ubuf *imu)
|
|
{
|
|
size_t len = req->rw.len;
|
|
u64 buf_end, buf_addr = req->rw.addr;
|
|
size_t offset;
|
|
|
|
if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
|
|
return -EFAULT;
|
|
/* not inside the mapped region */
|
|
if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
|
|
return -EFAULT;
|
|
|
|
/*
|
|
* May not be a start of buffer, set size appropriately
|
|
* and advance us to the beginning.
|
|
*/
|
|
offset = buf_addr - imu->ubuf;
|
|
iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
|
|
|
|
if (offset) {
|
|
/*
|
|
* Don't use iov_iter_advance() here, as it's really slow for
|
|
* using the latter parts of a big fixed buffer - it iterates
|
|
* over each segment manually. We can cheat a bit here, because
|
|
* we know that:
|
|
*
|
|
* 1) it's a BVEC iter, we set it up
|
|
* 2) all bvecs are PAGE_SIZE in size, except potentially the
|
|
* first and last bvec
|
|
*
|
|
* So just find our index, and adjust the iterator afterwards.
|
|
* If the offset is within the first bvec (or the whole first
|
|
* bvec, just use iov_iter_advance(). This makes it easier
|
|
* since we can just skip the first segment, which may not
|
|
* be PAGE_SIZE aligned.
|
|
*/
|
|
const struct bio_vec *bvec = imu->bvec;
|
|
|
|
if (offset <= bvec->bv_len) {
|
|
iov_iter_advance(iter, offset);
|
|
} else {
|
|
unsigned long seg_skip;
|
|
|
|
/* skip first vec */
|
|
offset -= bvec->bv_len;
|
|
seg_skip = 1 + (offset >> PAGE_SHIFT);
|
|
|
|
iter->bvec = bvec + seg_skip;
|
|
iter->nr_segs -= seg_skip;
|
|
iter->count -= bvec->bv_len + offset;
|
|
iter->iov_offset = offset & ~PAGE_MASK;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_mapped_ubuf *imu = req->imu;
|
|
u16 index, buf_index = req->buf_index;
|
|
|
|
if (likely(!imu)) {
|
|
if (unlikely(buf_index >= ctx->nr_user_bufs))
|
|
return -EFAULT;
|
|
index = array_index_nospec(buf_index, ctx->nr_user_bufs);
|
|
imu = READ_ONCE(ctx->user_bufs[index]);
|
|
req->imu = imu;
|
|
}
|
|
return __io_import_fixed(req, rw, iter, imu);
|
|
}
|
|
|
|
static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
|
|
{
|
|
if (needs_lock)
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
|
|
{
|
|
/*
|
|
* "Normal" inline submissions always hold the uring_lock, since we
|
|
* grab it from the system call. Same is true for the SQPOLL offload.
|
|
* The only exception is when we've detached the request and issue it
|
|
* from an async worker thread, grab the lock for that case.
|
|
*/
|
|
if (needs_lock)
|
|
mutex_lock(&ctx->uring_lock);
|
|
}
|
|
|
|
static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
|
|
int bgid, struct io_buffer *kbuf,
|
|
bool needs_lock)
|
|
{
|
|
struct io_buffer *head;
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
return kbuf;
|
|
|
|
io_ring_submit_lock(req->ctx, needs_lock);
|
|
|
|
lockdep_assert_held(&req->ctx->uring_lock);
|
|
|
|
head = xa_load(&req->ctx->io_buffers, bgid);
|
|
if (head) {
|
|
if (!list_empty(&head->list)) {
|
|
kbuf = list_last_entry(&head->list, struct io_buffer,
|
|
list);
|
|
list_del(&kbuf->list);
|
|
} else {
|
|
kbuf = head;
|
|
xa_erase(&req->ctx->io_buffers, bgid);
|
|
}
|
|
if (*len > kbuf->len)
|
|
*len = kbuf->len;
|
|
} else {
|
|
kbuf = ERR_PTR(-ENOBUFS);
|
|
}
|
|
|
|
io_ring_submit_unlock(req->ctx, needs_lock);
|
|
|
|
return kbuf;
|
|
}
|
|
|
|
static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
|
|
bool needs_lock)
|
|
{
|
|
struct io_buffer *kbuf;
|
|
u16 bgid;
|
|
|
|
kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
|
|
bgid = req->buf_index;
|
|
kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
|
|
if (IS_ERR(kbuf))
|
|
return kbuf;
|
|
req->rw.addr = (u64) (unsigned long) kbuf;
|
|
req->flags |= REQ_F_BUFFER_SELECTED;
|
|
return u64_to_user_ptr(kbuf->addr);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
|
|
bool needs_lock)
|
|
{
|
|
struct compat_iovec __user *uiov;
|
|
compat_ssize_t clen;
|
|
void __user *buf;
|
|
ssize_t len;
|
|
|
|
uiov = u64_to_user_ptr(req->rw.addr);
|
|
if (!access_ok(uiov, sizeof(*uiov)))
|
|
return -EFAULT;
|
|
if (__get_user(clen, &uiov->iov_len))
|
|
return -EFAULT;
|
|
if (clen < 0)
|
|
return -EINVAL;
|
|
|
|
len = clen;
|
|
buf = io_rw_buffer_select(req, &len, needs_lock);
|
|
if (IS_ERR(buf))
|
|
return PTR_ERR(buf);
|
|
iov[0].iov_base = buf;
|
|
iov[0].iov_len = (compat_size_t) len;
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
|
|
bool needs_lock)
|
|
{
|
|
struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
|
|
void __user *buf;
|
|
ssize_t len;
|
|
|
|
if (copy_from_user(iov, uiov, sizeof(*uiov)))
|
|
return -EFAULT;
|
|
|
|
len = iov[0].iov_len;
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
buf = io_rw_buffer_select(req, &len, needs_lock);
|
|
if (IS_ERR(buf))
|
|
return PTR_ERR(buf);
|
|
iov[0].iov_base = buf;
|
|
iov[0].iov_len = len;
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
|
|
bool needs_lock)
|
|
{
|
|
if (req->flags & REQ_F_BUFFER_SELECTED) {
|
|
struct io_buffer *kbuf;
|
|
|
|
kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
|
|
iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
|
|
iov[0].iov_len = kbuf->len;
|
|
return 0;
|
|
}
|
|
if (req->rw.len != 1)
|
|
return -EINVAL;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (req->ctx->compat)
|
|
return io_compat_import(req, iov, needs_lock);
|
|
#endif
|
|
|
|
return __io_iov_buffer_select(req, iov, needs_lock);
|
|
}
|
|
|
|
static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
|
|
struct iov_iter *iter, bool needs_lock)
|
|
{
|
|
void __user *buf = u64_to_user_ptr(req->rw.addr);
|
|
size_t sqe_len = req->rw.len;
|
|
u8 opcode = req->opcode;
|
|
ssize_t ret;
|
|
|
|
if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
|
|
*iovec = NULL;
|
|
return io_import_fixed(req, rw, iter);
|
|
}
|
|
|
|
/* buffer index only valid with fixed read/write, or buffer select */
|
|
if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
|
|
return -EINVAL;
|
|
|
|
if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
|
|
if (IS_ERR(buf))
|
|
return PTR_ERR(buf);
|
|
req->rw.len = sqe_len;
|
|
}
|
|
|
|
ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
|
|
*iovec = NULL;
|
|
return ret;
|
|
}
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
ret = io_iov_buffer_select(req, *iovec, needs_lock);
|
|
if (!ret)
|
|
iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
|
|
*iovec = NULL;
|
|
return ret;
|
|
}
|
|
|
|
return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
|
|
req->ctx->compat);
|
|
}
|
|
|
|
static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
|
|
{
|
|
return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
|
|
}
|
|
|
|
/*
|
|
* For files that don't have ->read_iter() and ->write_iter(), handle them
|
|
* by looping over ->read() or ->write() manually.
|
|
*/
|
|
static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
|
|
{
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
struct file *file = req->file;
|
|
ssize_t ret = 0;
|
|
|
|
/*
|
|
* Don't support polled IO through this interface, and we can't
|
|
* support non-blocking either. For the latter, this just causes
|
|
* the kiocb to be handled from an async context.
|
|
*/
|
|
if (kiocb->ki_flags & IOCB_HIPRI)
|
|
return -EOPNOTSUPP;
|
|
if (kiocb->ki_flags & IOCB_NOWAIT)
|
|
return -EAGAIN;
|
|
|
|
while (iov_iter_count(iter)) {
|
|
struct iovec iovec;
|
|
ssize_t nr;
|
|
|
|
if (!iov_iter_is_bvec(iter)) {
|
|
iovec = iov_iter_iovec(iter);
|
|
} else {
|
|
iovec.iov_base = u64_to_user_ptr(req->rw.addr);
|
|
iovec.iov_len = req->rw.len;
|
|
}
|
|
|
|
if (rw == READ) {
|
|
nr = file->f_op->read(file, iovec.iov_base,
|
|
iovec.iov_len, io_kiocb_ppos(kiocb));
|
|
} else {
|
|
nr = file->f_op->write(file, iovec.iov_base,
|
|
iovec.iov_len, io_kiocb_ppos(kiocb));
|
|
}
|
|
|
|
if (nr < 0) {
|
|
if (!ret)
|
|
ret = nr;
|
|
break;
|
|
}
|
|
ret += nr;
|
|
if (nr != iovec.iov_len)
|
|
break;
|
|
req->rw.len -= nr;
|
|
req->rw.addr += nr;
|
|
iov_iter_advance(iter, nr);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
|
|
const struct iovec *fast_iov, struct iov_iter *iter)
|
|
{
|
|
struct io_async_rw *rw = req->async_data;
|
|
|
|
memcpy(&rw->iter, iter, sizeof(*iter));
|
|
rw->free_iovec = iovec;
|
|
rw->bytes_done = 0;
|
|
/* can only be fixed buffers, no need to do anything */
|
|
if (iov_iter_is_bvec(iter))
|
|
return;
|
|
if (!iovec) {
|
|
unsigned iov_off = 0;
|
|
|
|
rw->iter.iov = rw->fast_iov;
|
|
if (iter->iov != fast_iov) {
|
|
iov_off = iter->iov - fast_iov;
|
|
rw->iter.iov += iov_off;
|
|
}
|
|
if (rw->fast_iov != fast_iov)
|
|
memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
|
|
sizeof(struct iovec) * iter->nr_segs);
|
|
} else {
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
}
|
|
}
|
|
|
|
static inline int io_alloc_async_data(struct io_kiocb *req)
|
|
{
|
|
WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
|
|
req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
|
|
return req->async_data == NULL;
|
|
}
|
|
|
|
static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
|
|
const struct iovec *fast_iov,
|
|
struct iov_iter *iter, bool force)
|
|
{
|
|
if (!force && !io_op_defs[req->opcode].needs_async_setup)
|
|
return 0;
|
|
if (!req->async_data) {
|
|
if (io_alloc_async_data(req)) {
|
|
kfree(iovec);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
io_req_map_rw(req, iovec, fast_iov, iter);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
|
|
{
|
|
struct io_async_rw *iorw = req->async_data;
|
|
struct iovec *iov = iorw->fast_iov;
|
|
int ret;
|
|
|
|
ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
|
|
if (unlikely(ret < 0))
|
|
return ret;
|
|
|
|
iorw->bytes_done = 0;
|
|
iorw->free_iovec = iov;
|
|
if (iov)
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return 0;
|
|
}
|
|
|
|
static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(!(req->file->f_mode & FMODE_READ)))
|
|
return -EBADF;
|
|
return io_prep_rw(req, sqe);
|
|
}
|
|
|
|
/*
|
|
* This is our waitqueue callback handler, registered through lock_page_async()
|
|
* when we initially tried to do the IO with the iocb armed our waitqueue.
|
|
* This gets called when the page is unlocked, and we generally expect that to
|
|
* happen when the page IO is completed and the page is now uptodate. This will
|
|
* queue a task_work based retry of the operation, attempting to copy the data
|
|
* again. If the latter fails because the page was NOT uptodate, then we will
|
|
* do a thread based blocking retry of the operation. That's the unexpected
|
|
* slow path.
|
|
*/
|
|
static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
|
|
int sync, void *arg)
|
|
{
|
|
struct wait_page_queue *wpq;
|
|
struct io_kiocb *req = wait->private;
|
|
struct wait_page_key *key = arg;
|
|
|
|
wpq = container_of(wait, struct wait_page_queue, wait);
|
|
|
|
if (!wake_page_match(wpq, key))
|
|
return 0;
|
|
|
|
req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
|
|
list_del_init(&wait->entry);
|
|
|
|
/* submit ref gets dropped, acquire a new one */
|
|
req_ref_get(req);
|
|
io_req_task_queue(req);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* This controls whether a given IO request should be armed for async page
|
|
* based retry. If we return false here, the request is handed to the async
|
|
* worker threads for retry. If we're doing buffered reads on a regular file,
|
|
* we prepare a private wait_page_queue entry and retry the operation. This
|
|
* will either succeed because the page is now uptodate and unlocked, or it
|
|
* will register a callback when the page is unlocked at IO completion. Through
|
|
* that callback, io_uring uses task_work to setup a retry of the operation.
|
|
* That retry will attempt the buffered read again. The retry will generally
|
|
* succeed, or in rare cases where it fails, we then fall back to using the
|
|
* async worker threads for a blocking retry.
|
|
*/
|
|
static bool io_rw_should_retry(struct io_kiocb *req)
|
|
{
|
|
struct io_async_rw *rw = req->async_data;
|
|
struct wait_page_queue *wait = &rw->wpq;
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
|
|
/* never retry for NOWAIT, we just complete with -EAGAIN */
|
|
if (req->flags & REQ_F_NOWAIT)
|
|
return false;
|
|
|
|
/* Only for buffered IO */
|
|
if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
|
|
return false;
|
|
|
|
/*
|
|
* just use poll if we can, and don't attempt if the fs doesn't
|
|
* support callback based unlocks
|
|
*/
|
|
if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
|
|
return false;
|
|
|
|
wait->wait.func = io_async_buf_func;
|
|
wait->wait.private = req;
|
|
wait->wait.flags = 0;
|
|
INIT_LIST_HEAD(&wait->wait.entry);
|
|
kiocb->ki_flags |= IOCB_WAITQ;
|
|
kiocb->ki_flags &= ~IOCB_NOWAIT;
|
|
kiocb->ki_waitq = wait;
|
|
return true;
|
|
}
|
|
|
|
static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
|
|
{
|
|
if (req->file->f_op->read_iter)
|
|
return call_read_iter(req->file, &req->rw.kiocb, iter);
|
|
else if (req->file->f_op->read)
|
|
return loop_rw_iter(READ, req, iter);
|
|
else
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int io_read(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
struct iov_iter __iter, *iter = &__iter;
|
|
struct io_async_rw *rw = req->async_data;
|
|
ssize_t io_size, ret, ret2;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
if (rw) {
|
|
iter = &rw->iter;
|
|
iovec = NULL;
|
|
} else {
|
|
ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
io_size = iov_iter_count(iter);
|
|
req->result = io_size;
|
|
|
|
/* Ensure we clear previously set non-block flag */
|
|
if (!force_nonblock)
|
|
kiocb->ki_flags &= ~IOCB_NOWAIT;
|
|
else
|
|
kiocb->ki_flags |= IOCB_NOWAIT;
|
|
|
|
/* If the file doesn't support async, just async punt */
|
|
if (force_nonblock && !io_file_supports_async(req, READ)) {
|
|
ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
|
|
return ret ?: -EAGAIN;
|
|
}
|
|
|
|
ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
|
|
if (unlikely(ret)) {
|
|
kfree(iovec);
|
|
return ret;
|
|
}
|
|
|
|
ret = io_iter_do_read(req, iter);
|
|
|
|
if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
|
|
req->flags &= ~REQ_F_REISSUE;
|
|
/* IOPOLL retry should happen for io-wq threads */
|
|
if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
goto done;
|
|
/* no retry on NONBLOCK nor RWF_NOWAIT */
|
|
if (req->flags & REQ_F_NOWAIT)
|
|
goto done;
|
|
/* some cases will consume bytes even on error returns */
|
|
iov_iter_revert(iter, io_size - iov_iter_count(iter));
|
|
ret = 0;
|
|
} else if (ret == -EIOCBQUEUED) {
|
|
goto out_free;
|
|
} else if (ret <= 0 || ret == io_size || !force_nonblock ||
|
|
(req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {
|
|
/* read all, failed, already did sync or don't want to retry */
|
|
goto done;
|
|
}
|
|
|
|
ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
|
|
if (ret2)
|
|
return ret2;
|
|
|
|
iovec = NULL;
|
|
rw = req->async_data;
|
|
/* now use our persistent iterator, if we aren't already */
|
|
iter = &rw->iter;
|
|
|
|
do {
|
|
io_size -= ret;
|
|
rw->bytes_done += ret;
|
|
/* if we can retry, do so with the callbacks armed */
|
|
if (!io_rw_should_retry(req)) {
|
|
kiocb->ki_flags &= ~IOCB_WAITQ;
|
|
return -EAGAIN;
|
|
}
|
|
|
|
/*
|
|
* Now retry read with the IOCB_WAITQ parts set in the iocb. If
|
|
* we get -EIOCBQUEUED, then we'll get a notification when the
|
|
* desired page gets unlocked. We can also get a partial read
|
|
* here, and if we do, then just retry at the new offset.
|
|
*/
|
|
ret = io_iter_do_read(req, iter);
|
|
if (ret == -EIOCBQUEUED)
|
|
return 0;
|
|
/* we got some bytes, but not all. retry. */
|
|
kiocb->ki_flags &= ~IOCB_WAITQ;
|
|
} while (ret > 0 && ret < io_size);
|
|
done:
|
|
kiocb_done(kiocb, ret, issue_flags);
|
|
out_free:
|
|
/* it's faster to check here then delegate to kfree */
|
|
if (iovec)
|
|
kfree(iovec);
|
|
return 0;
|
|
}
|
|
|
|
static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
|
|
return -EBADF;
|
|
return io_prep_rw(req, sqe);
|
|
}
|
|
|
|
static int io_write(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
|
|
struct kiocb *kiocb = &req->rw.kiocb;
|
|
struct iov_iter __iter, *iter = &__iter;
|
|
struct io_async_rw *rw = req->async_data;
|
|
ssize_t ret, ret2, io_size;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
if (rw) {
|
|
iter = &rw->iter;
|
|
iovec = NULL;
|
|
} else {
|
|
ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
io_size = iov_iter_count(iter);
|
|
req->result = io_size;
|
|
|
|
/* Ensure we clear previously set non-block flag */
|
|
if (!force_nonblock)
|
|
kiocb->ki_flags &= ~IOCB_NOWAIT;
|
|
else
|
|
kiocb->ki_flags |= IOCB_NOWAIT;
|
|
|
|
/* If the file doesn't support async, just async punt */
|
|
if (force_nonblock && !io_file_supports_async(req, WRITE))
|
|
goto copy_iov;
|
|
|
|
/* file path doesn't support NOWAIT for non-direct_IO */
|
|
if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
|
|
(req->flags & REQ_F_ISREG))
|
|
goto copy_iov;
|
|
|
|
ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
|
|
if (unlikely(ret))
|
|
goto out_free;
|
|
|
|
/*
|
|
* Open-code file_start_write here to grab freeze protection,
|
|
* which will be released by another thread in
|
|
* io_complete_rw(). Fool lockdep by telling it the lock got
|
|
* released so that it doesn't complain about the held lock when
|
|
* we return to userspace.
|
|
*/
|
|
if (req->flags & REQ_F_ISREG) {
|
|
sb_start_write(file_inode(req->file)->i_sb);
|
|
__sb_writers_release(file_inode(req->file)->i_sb,
|
|
SB_FREEZE_WRITE);
|
|
}
|
|
kiocb->ki_flags |= IOCB_WRITE;
|
|
|
|
if (req->file->f_op->write_iter)
|
|
ret2 = call_write_iter(req->file, kiocb, iter);
|
|
else if (req->file->f_op->write)
|
|
ret2 = loop_rw_iter(WRITE, req, iter);
|
|
else
|
|
ret2 = -EINVAL;
|
|
|
|
if (req->flags & REQ_F_REISSUE) {
|
|
req->flags &= ~REQ_F_REISSUE;
|
|
ret2 = -EAGAIN;
|
|
}
|
|
|
|
/*
|
|
* Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
|
|
* retry them without IOCB_NOWAIT.
|
|
*/
|
|
if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
|
|
ret2 = -EAGAIN;
|
|
/* no retry on NONBLOCK nor RWF_NOWAIT */
|
|
if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
|
|
goto done;
|
|
if (!force_nonblock || ret2 != -EAGAIN) {
|
|
/* IOPOLL retry should happen for io-wq threads */
|
|
if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
|
|
goto copy_iov;
|
|
done:
|
|
kiocb_done(kiocb, ret2, issue_flags);
|
|
} else {
|
|
copy_iov:
|
|
/* some cases will consume bytes even on error returns */
|
|
iov_iter_revert(iter, io_size - iov_iter_count(iter));
|
|
ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
|
|
return ret ?: -EAGAIN;
|
|
}
|
|
out_free:
|
|
/* it's reportedly faster than delegating the null check to kfree() */
|
|
if (iovec)
|
|
kfree(iovec);
|
|
return ret;
|
|
}
|
|
|
|
static int io_renameat_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_rename *ren = &req->rename;
|
|
const char __user *oldf, *newf;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index)
|
|
return -EINVAL;
|
|
if (unlikely(req->flags & REQ_F_FIXED_FILE))
|
|
return -EBADF;
|
|
|
|
ren->old_dfd = READ_ONCE(sqe->fd);
|
|
oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
|
|
ren->new_dfd = READ_ONCE(sqe->len);
|
|
ren->flags = READ_ONCE(sqe->rename_flags);
|
|
|
|
ren->oldpath = getname(oldf);
|
|
if (IS_ERR(ren->oldpath))
|
|
return PTR_ERR(ren->oldpath);
|
|
|
|
ren->newpath = getname(newf);
|
|
if (IS_ERR(ren->newpath)) {
|
|
putname(ren->oldpath);
|
|
return PTR_ERR(ren->newpath);
|
|
}
|
|
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return 0;
|
|
}
|
|
|
|
static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_rename *ren = &req->rename;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
|
|
ren->newpath, ren->flags);
|
|
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int io_unlinkat_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_unlink *un = &req->unlink;
|
|
const char __user *fname;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
|
|
return -EINVAL;
|
|
if (unlikely(req->flags & REQ_F_FIXED_FILE))
|
|
return -EBADF;
|
|
|
|
un->dfd = READ_ONCE(sqe->fd);
|
|
|
|
un->flags = READ_ONCE(sqe->unlink_flags);
|
|
if (un->flags & ~AT_REMOVEDIR)
|
|
return -EINVAL;
|
|
|
|
fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
un->filename = getname(fname);
|
|
if (IS_ERR(un->filename))
|
|
return PTR_ERR(un->filename);
|
|
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return 0;
|
|
}
|
|
|
|
static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_unlink *un = &req->unlink;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
if (un->flags & AT_REMOVEDIR)
|
|
ret = do_rmdir(un->dfd, un->filename);
|
|
else
|
|
ret = do_unlinkat(un->dfd, un->filename);
|
|
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int io_shutdown_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
#if defined(CONFIG_NET)
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
|
|
sqe->buf_index)
|
|
return -EINVAL;
|
|
|
|
req->shutdown.how = READ_ONCE(sqe->len);
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
#if defined(CONFIG_NET)
|
|
struct socket *sock;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
sock = sock_from_file(req->file);
|
|
if (unlikely(!sock))
|
|
return -ENOTSOCK;
|
|
|
|
ret = __sys_shutdown_sock(sock, req->shutdown.how);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int __io_splice_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_splice *sp = &req->splice;
|
|
unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
sp->file_in = NULL;
|
|
sp->len = READ_ONCE(sqe->len);
|
|
sp->flags = READ_ONCE(sqe->splice_flags);
|
|
|
|
if (unlikely(sp->flags & ~valid_flags))
|
|
return -EINVAL;
|
|
|
|
sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in),
|
|
(sp->flags & SPLICE_F_FD_IN_FIXED));
|
|
if (!sp->file_in)
|
|
return -EBADF;
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return 0;
|
|
}
|
|
|
|
static int io_tee_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
|
|
return -EINVAL;
|
|
return __io_splice_prep(req, sqe);
|
|
}
|
|
|
|
static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_splice *sp = &req->splice;
|
|
struct file *in = sp->file_in;
|
|
struct file *out = sp->file_out;
|
|
unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
|
|
long ret = 0;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
if (sp->len)
|
|
ret = do_tee(in, out, sp->len, flags);
|
|
|
|
if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
|
|
io_put_file(in);
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
|
|
if (ret != sp->len)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_splice *sp = &req->splice;
|
|
|
|
sp->off_in = READ_ONCE(sqe->splice_off_in);
|
|
sp->off_out = READ_ONCE(sqe->off);
|
|
return __io_splice_prep(req, sqe);
|
|
}
|
|
|
|
static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_splice *sp = &req->splice;
|
|
struct file *in = sp->file_in;
|
|
struct file *out = sp->file_out;
|
|
unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
|
|
loff_t *poff_in, *poff_out;
|
|
long ret = 0;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
|
|
poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
|
|
|
|
if (sp->len)
|
|
ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
|
|
|
|
if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
|
|
io_put_file(in);
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
|
|
if (ret != sp->len)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* IORING_OP_NOP just posts a completion event, nothing else.
|
|
*/
|
|
static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
__io_req_complete(req, issue_flags, 0, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (!req->file)
|
|
return -EBADF;
|
|
|
|
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
|
|
return -EINVAL;
|
|
|
|
req->sync.flags = READ_ONCE(sqe->fsync_flags);
|
|
if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
|
|
return -EINVAL;
|
|
|
|
req->sync.off = READ_ONCE(sqe->off);
|
|
req->sync.len = READ_ONCE(sqe->len);
|
|
return 0;
|
|
}
|
|
|
|
static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
loff_t end = req->sync.off + req->sync.len;
|
|
int ret;
|
|
|
|
/* fsync always requires a blocking context */
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = vfs_fsync_range(req->file, req->sync.off,
|
|
end > 0 ? end : LLONG_MAX,
|
|
req->sync.flags & IORING_FSYNC_DATASYNC);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int io_fallocate_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
|
|
return -EINVAL;
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
req->sync.off = READ_ONCE(sqe->off);
|
|
req->sync.len = READ_ONCE(sqe->addr);
|
|
req->sync.mode = READ_ONCE(sqe->len);
|
|
return 0;
|
|
}
|
|
|
|
static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
int ret;
|
|
|
|
/* fallocate always requiring blocking context */
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
|
|
req->sync.len);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
const char __user *fname;
|
|
int ret;
|
|
|
|
if (unlikely(sqe->ioprio || sqe->buf_index))
|
|
return -EINVAL;
|
|
if (unlikely(req->flags & REQ_F_FIXED_FILE))
|
|
return -EBADF;
|
|
|
|
/* open.how should be already initialised */
|
|
if (!(req->open.how.flags & O_PATH) && force_o_largefile())
|
|
req->open.how.flags |= O_LARGEFILE;
|
|
|
|
req->open.dfd = READ_ONCE(sqe->fd);
|
|
fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
req->open.filename = getname(fname);
|
|
if (IS_ERR(req->open.filename)) {
|
|
ret = PTR_ERR(req->open.filename);
|
|
req->open.filename = NULL;
|
|
return ret;
|
|
}
|
|
req->open.nofile = rlimit(RLIMIT_NOFILE);
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return 0;
|
|
}
|
|
|
|
static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
u64 flags, mode;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
mode = READ_ONCE(sqe->len);
|
|
flags = READ_ONCE(sqe->open_flags);
|
|
req->open.how = build_open_how(flags, mode);
|
|
return __io_openat_prep(req, sqe);
|
|
}
|
|
|
|
static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct open_how __user *how;
|
|
size_t len;
|
|
int ret;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
|
|
len = READ_ONCE(sqe->len);
|
|
if (len < OPEN_HOW_SIZE_VER0)
|
|
return -EINVAL;
|
|
|
|
ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
|
|
len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return __io_openat_prep(req, sqe);
|
|
}
|
|
|
|
static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct open_flags op;
|
|
struct file *file;
|
|
bool nonblock_set;
|
|
bool resolve_nonblock;
|
|
int ret;
|
|
|
|
ret = build_open_flags(&req->open.how, &op);
|
|
if (ret)
|
|
goto err;
|
|
nonblock_set = op.open_flag & O_NONBLOCK;
|
|
resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
|
|
if (issue_flags & IO_URING_F_NONBLOCK) {
|
|
/*
|
|
* Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
|
|
* it'll always -EAGAIN
|
|
*/
|
|
if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
|
|
return -EAGAIN;
|
|
op.lookup_flags |= LOOKUP_CACHED;
|
|
op.open_flag |= O_NONBLOCK;
|
|
}
|
|
|
|
ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
|
|
if (ret < 0)
|
|
goto err;
|
|
|
|
file = do_filp_open(req->open.dfd, req->open.filename, &op);
|
|
if (IS_ERR(file)) {
|
|
/*
|
|
* We could hang on to this 'fd' on retrying, but seems like
|
|
* marginal gain for something that is now known to be a slower
|
|
* path. So just put it, and we'll get a new one when we retry.
|
|
*/
|
|
put_unused_fd(ret);
|
|
|
|
ret = PTR_ERR(file);
|
|
/* only retry if RESOLVE_CACHED wasn't already set by application */
|
|
if (ret == -EAGAIN &&
|
|
(!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
|
|
return -EAGAIN;
|
|
goto err;
|
|
}
|
|
|
|
if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
|
|
file->f_flags &= ~O_NONBLOCK;
|
|
fsnotify_open(file);
|
|
fd_install(ret, file);
|
|
err:
|
|
putname(req->open.filename);
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
return io_openat2(req, issue_flags);
|
|
}
|
|
|
|
static int io_remove_buffers_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_provide_buf *p = &req->pbuf;
|
|
u64 tmp;
|
|
|
|
if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
|
|
return -EINVAL;
|
|
|
|
tmp = READ_ONCE(sqe->fd);
|
|
if (!tmp || tmp > USHRT_MAX)
|
|
return -EINVAL;
|
|
|
|
memset(p, 0, sizeof(*p));
|
|
p->nbufs = tmp;
|
|
p->bgid = READ_ONCE(sqe->buf_group);
|
|
return 0;
|
|
}
|
|
|
|
static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
|
|
int bgid, unsigned nbufs)
|
|
{
|
|
unsigned i = 0;
|
|
|
|
/* shouldn't happen */
|
|
if (!nbufs)
|
|
return 0;
|
|
|
|
/* the head kbuf is the list itself */
|
|
while (!list_empty(&buf->list)) {
|
|
struct io_buffer *nxt;
|
|
|
|
nxt = list_first_entry(&buf->list, struct io_buffer, list);
|
|
list_del(&nxt->list);
|
|
kfree(nxt);
|
|
if (++i == nbufs)
|
|
return i;
|
|
}
|
|
i++;
|
|
kfree(buf);
|
|
xa_erase(&ctx->io_buffers, bgid);
|
|
|
|
return i;
|
|
}
|
|
|
|
static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_provide_buf *p = &req->pbuf;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_buffer *head;
|
|
int ret = 0;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
io_ring_submit_lock(ctx, !force_nonblock);
|
|
|
|
lockdep_assert_held(&ctx->uring_lock);
|
|
|
|
ret = -ENOENT;
|
|
head = xa_load(&ctx->io_buffers, p->bgid);
|
|
if (head)
|
|
ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
|
|
/* complete before unlock, IOPOLL may need the lock */
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
io_ring_submit_unlock(ctx, !force_nonblock);
|
|
return 0;
|
|
}
|
|
|
|
static int io_provide_buffers_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
unsigned long size, tmp_check;
|
|
struct io_provide_buf *p = &req->pbuf;
|
|
u64 tmp;
|
|
|
|
if (sqe->ioprio || sqe->rw_flags)
|
|
return -EINVAL;
|
|
|
|
tmp = READ_ONCE(sqe->fd);
|
|
if (!tmp || tmp > USHRT_MAX)
|
|
return -E2BIG;
|
|
p->nbufs = tmp;
|
|
p->addr = READ_ONCE(sqe->addr);
|
|
p->len = READ_ONCE(sqe->len);
|
|
|
|
if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
|
|
&size))
|
|
return -EOVERFLOW;
|
|
if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
|
|
return -EOVERFLOW;
|
|
|
|
size = (unsigned long)p->len * p->nbufs;
|
|
if (!access_ok(u64_to_user_ptr(p->addr), size))
|
|
return -EFAULT;
|
|
|
|
p->bgid = READ_ONCE(sqe->buf_group);
|
|
tmp = READ_ONCE(sqe->off);
|
|
if (tmp > USHRT_MAX)
|
|
return -E2BIG;
|
|
p->bid = tmp;
|
|
return 0;
|
|
}
|
|
|
|
static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
|
|
{
|
|
struct io_buffer *buf;
|
|
u64 addr = pbuf->addr;
|
|
int i, bid = pbuf->bid;
|
|
|
|
for (i = 0; i < pbuf->nbufs; i++) {
|
|
buf = kmalloc(sizeof(*buf), GFP_KERNEL);
|
|
if (!buf)
|
|
break;
|
|
|
|
buf->addr = addr;
|
|
buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
|
|
buf->bid = bid;
|
|
addr += pbuf->len;
|
|
bid++;
|
|
if (!*head) {
|
|
INIT_LIST_HEAD(&buf->list);
|
|
*head = buf;
|
|
} else {
|
|
list_add_tail(&buf->list, &(*head)->list);
|
|
}
|
|
}
|
|
|
|
return i ? i : -ENOMEM;
|
|
}
|
|
|
|
static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_provide_buf *p = &req->pbuf;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_buffer *head, *list;
|
|
int ret = 0;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
io_ring_submit_lock(ctx, !force_nonblock);
|
|
|
|
lockdep_assert_held(&ctx->uring_lock);
|
|
|
|
list = head = xa_load(&ctx->io_buffers, p->bgid);
|
|
|
|
ret = io_add_buffers(p, &head);
|
|
if (ret >= 0 && !list) {
|
|
ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
|
|
if (ret < 0)
|
|
__io_remove_buffers(ctx, head, p->bgid, -1U);
|
|
}
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
/* complete before unlock, IOPOLL may need the lock */
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
io_ring_submit_unlock(ctx, !force_nonblock);
|
|
return 0;
|
|
}
|
|
|
|
static int io_epoll_ctl_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
#if defined(CONFIG_EPOLL)
|
|
if (sqe->ioprio || sqe->buf_index)
|
|
return -EINVAL;
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
req->epoll.epfd = READ_ONCE(sqe->fd);
|
|
req->epoll.op = READ_ONCE(sqe->len);
|
|
req->epoll.fd = READ_ONCE(sqe->off);
|
|
|
|
if (ep_op_has_event(req->epoll.op)) {
|
|
struct epoll_event __user *ev;
|
|
|
|
ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
|
|
return -EFAULT;
|
|
}
|
|
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
#if defined(CONFIG_EPOLL)
|
|
struct io_epoll *ie = &req->epoll;
|
|
int ret;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
|
|
if (force_nonblock && ret == -EAGAIN)
|
|
return -EAGAIN;
|
|
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
|
|
if (sqe->ioprio || sqe->buf_index || sqe->off)
|
|
return -EINVAL;
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
req->madvise.addr = READ_ONCE(sqe->addr);
|
|
req->madvise.len = READ_ONCE(sqe->len);
|
|
req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
|
|
struct io_madvise *ma = &req->madvise;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
if (sqe->ioprio || sqe->buf_index || sqe->addr)
|
|
return -EINVAL;
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
req->fadvise.offset = READ_ONCE(sqe->off);
|
|
req->fadvise.len = READ_ONCE(sqe->len);
|
|
req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
|
|
return 0;
|
|
}
|
|
|
|
static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_fadvise *fa = &req->fadvise;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK) {
|
|
switch (fa->advice) {
|
|
case POSIX_FADV_NORMAL:
|
|
case POSIX_FADV_RANDOM:
|
|
case POSIX_FADV_SEQUENTIAL:
|
|
break;
|
|
default:
|
|
return -EAGAIN;
|
|
}
|
|
}
|
|
|
|
ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index)
|
|
return -EINVAL;
|
|
if (req->flags & REQ_F_FIXED_FILE)
|
|
return -EBADF;
|
|
|
|
req->statx.dfd = READ_ONCE(sqe->fd);
|
|
req->statx.mask = READ_ONCE(sqe->len);
|
|
req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
|
|
req->statx.flags = READ_ONCE(sqe->statx_flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_statx *ctx = &req->statx;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
|
|
ctx->buffer);
|
|
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
|
|
sqe->rw_flags || sqe->buf_index)
|
|
return -EINVAL;
|
|
if (req->flags & REQ_F_FIXED_FILE)
|
|
return -EBADF;
|
|
|
|
req->close.fd = READ_ONCE(sqe->fd);
|
|
return 0;
|
|
}
|
|
|
|
static int io_close(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct files_struct *files = current->files;
|
|
struct io_close *close = &req->close;
|
|
struct fdtable *fdt;
|
|
struct file *file = NULL;
|
|
int ret = -EBADF;
|
|
|
|
spin_lock(&files->file_lock);
|
|
fdt = files_fdtable(files);
|
|
if (close->fd >= fdt->max_fds) {
|
|
spin_unlock(&files->file_lock);
|
|
goto err;
|
|
}
|
|
file = fdt->fd[close->fd];
|
|
if (!file || file->f_op == &io_uring_fops) {
|
|
spin_unlock(&files->file_lock);
|
|
file = NULL;
|
|
goto err;
|
|
}
|
|
|
|
/* if the file has a flush method, be safe and punt to async */
|
|
if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
|
|
spin_unlock(&files->file_lock);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
ret = __close_fd_get_file(close->fd, &file);
|
|
spin_unlock(&files->file_lock);
|
|
if (ret < 0) {
|
|
if (ret == -ENOENT)
|
|
ret = -EBADF;
|
|
goto err;
|
|
}
|
|
|
|
/* No ->flush() or already async, safely close from here */
|
|
ret = filp_close(file, current->files);
|
|
err:
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
if (file)
|
|
fput(file);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
|
|
return -EINVAL;
|
|
|
|
req->sync.off = READ_ONCE(sqe->off);
|
|
req->sync.len = READ_ONCE(sqe->len);
|
|
req->sync.flags = READ_ONCE(sqe->sync_range_flags);
|
|
return 0;
|
|
}
|
|
|
|
static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
int ret;
|
|
|
|
/* sync_file_range always requires a blocking context */
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = sync_file_range(req->file, req->sync.off, req->sync.len,
|
|
req->sync.flags);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
|
|
#if defined(CONFIG_NET)
|
|
static int io_setup_async_msg(struct io_kiocb *req,
|
|
struct io_async_msghdr *kmsg)
|
|
{
|
|
struct io_async_msghdr *async_msg = req->async_data;
|
|
|
|
if (async_msg)
|
|
return -EAGAIN;
|
|
if (io_alloc_async_data(req)) {
|
|
kfree(kmsg->free_iov);
|
|
return -ENOMEM;
|
|
}
|
|
async_msg = req->async_data;
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
memcpy(async_msg, kmsg, sizeof(*kmsg));
|
|
async_msg->msg.msg_name = &async_msg->addr;
|
|
/* if were using fast_iov, set it to the new one */
|
|
if (!async_msg->free_iov)
|
|
async_msg->msg.msg_iter.iov = async_msg->fast_iov;
|
|
|
|
return -EAGAIN;
|
|
}
|
|
|
|
static int io_sendmsg_copy_hdr(struct io_kiocb *req,
|
|
struct io_async_msghdr *iomsg)
|
|
{
|
|
iomsg->msg.msg_name = &iomsg->addr;
|
|
iomsg->free_iov = iomsg->fast_iov;
|
|
return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
|
|
req->sr_msg.msg_flags, &iomsg->free_iov);
|
|
}
|
|
|
|
static int io_sendmsg_prep_async(struct io_kiocb *req)
|
|
{
|
|
int ret;
|
|
|
|
ret = io_sendmsg_copy_hdr(req, req->async_data);
|
|
if (!ret)
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return ret;
|
|
}
|
|
|
|
static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
sr->len = READ_ONCE(sqe->len);
|
|
sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
|
|
if (sr->msg_flags & MSG_DONTWAIT)
|
|
req->flags |= REQ_F_NOWAIT;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (req->ctx->compat)
|
|
sr->msg_flags |= MSG_CMSG_COMPAT;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_async_msghdr iomsg, *kmsg;
|
|
struct socket *sock;
|
|
unsigned flags;
|
|
int min_ret = 0;
|
|
int ret;
|
|
|
|
sock = sock_from_file(req->file);
|
|
if (unlikely(!sock))
|
|
return -ENOTSOCK;
|
|
|
|
kmsg = req->async_data;
|
|
if (!kmsg) {
|
|
ret = io_sendmsg_copy_hdr(req, &iomsg);
|
|
if (ret)
|
|
return ret;
|
|
kmsg = &iomsg;
|
|
}
|
|
|
|
flags = req->sr_msg.msg_flags;
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
flags |= MSG_DONTWAIT;
|
|
if (flags & MSG_WAITALL)
|
|
min_ret = iov_iter_count(&kmsg->msg.msg_iter);
|
|
|
|
ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
|
|
if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
|
|
return io_setup_async_msg(req, kmsg);
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
|
|
/* fast path, check for non-NULL to avoid function call */
|
|
if (kmsg->free_iov)
|
|
kfree(kmsg->free_iov);
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
if (ret < min_ret)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_send(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
struct msghdr msg;
|
|
struct iovec iov;
|
|
struct socket *sock;
|
|
unsigned flags;
|
|
int min_ret = 0;
|
|
int ret;
|
|
|
|
sock = sock_from_file(req->file);
|
|
if (unlikely(!sock))
|
|
return -ENOTSOCK;
|
|
|
|
ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
|
|
msg.msg_name = NULL;
|
|
msg.msg_control = NULL;
|
|
msg.msg_controllen = 0;
|
|
msg.msg_namelen = 0;
|
|
|
|
flags = req->sr_msg.msg_flags;
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
flags |= MSG_DONTWAIT;
|
|
if (flags & MSG_WAITALL)
|
|
min_ret = iov_iter_count(&msg.msg_iter);
|
|
|
|
msg.msg_flags = flags;
|
|
ret = sock_sendmsg(sock, &msg);
|
|
if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
|
|
return -EAGAIN;
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
|
|
if (ret < min_ret)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
|
|
struct io_async_msghdr *iomsg)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
struct iovec __user *uiov;
|
|
size_t iov_len;
|
|
int ret;
|
|
|
|
ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
|
|
&iomsg->uaddr, &uiov, &iov_len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
if (iov_len > 1)
|
|
return -EINVAL;
|
|
if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
|
|
return -EFAULT;
|
|
sr->len = iomsg->fast_iov[0].iov_len;
|
|
iomsg->free_iov = NULL;
|
|
} else {
|
|
iomsg->free_iov = iomsg->fast_iov;
|
|
ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
|
|
&iomsg->free_iov, &iomsg->msg.msg_iter,
|
|
false);
|
|
if (ret > 0)
|
|
ret = 0;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
|
|
struct io_async_msghdr *iomsg)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
struct compat_iovec __user *uiov;
|
|
compat_uptr_t ptr;
|
|
compat_size_t len;
|
|
int ret;
|
|
|
|
ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
|
|
&ptr, &len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
uiov = compat_ptr(ptr);
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
compat_ssize_t clen;
|
|
|
|
if (len > 1)
|
|
return -EINVAL;
|
|
if (!access_ok(uiov, sizeof(*uiov)))
|
|
return -EFAULT;
|
|
if (__get_user(clen, &uiov->iov_len))
|
|
return -EFAULT;
|
|
if (clen < 0)
|
|
return -EINVAL;
|
|
sr->len = clen;
|
|
iomsg->free_iov = NULL;
|
|
} else {
|
|
iomsg->free_iov = iomsg->fast_iov;
|
|
ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
|
|
UIO_FASTIOV, &iomsg->free_iov,
|
|
&iomsg->msg.msg_iter, true);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static int io_recvmsg_copy_hdr(struct io_kiocb *req,
|
|
struct io_async_msghdr *iomsg)
|
|
{
|
|
iomsg->msg.msg_name = &iomsg->addr;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (req->ctx->compat)
|
|
return __io_compat_recvmsg_copy_hdr(req, iomsg);
|
|
#endif
|
|
|
|
return __io_recvmsg_copy_hdr(req, iomsg);
|
|
}
|
|
|
|
static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
|
|
bool needs_lock)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
struct io_buffer *kbuf;
|
|
|
|
kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
|
|
if (IS_ERR(kbuf))
|
|
return kbuf;
|
|
|
|
sr->kbuf = kbuf;
|
|
req->flags |= REQ_F_BUFFER_SELECTED;
|
|
return kbuf;
|
|
}
|
|
|
|
static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
|
|
{
|
|
return io_put_kbuf(req, req->sr_msg.kbuf);
|
|
}
|
|
|
|
static int io_recvmsg_prep_async(struct io_kiocb *req)
|
|
{
|
|
int ret;
|
|
|
|
ret = io_recvmsg_copy_hdr(req, req->async_data);
|
|
if (!ret)
|
|
req->flags |= REQ_F_NEED_CLEANUP;
|
|
return ret;
|
|
}
|
|
|
|
static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
|
|
sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
sr->len = READ_ONCE(sqe->len);
|
|
sr->bgid = READ_ONCE(sqe->buf_group);
|
|
sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
|
|
if (sr->msg_flags & MSG_DONTWAIT)
|
|
req->flags |= REQ_F_NOWAIT;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (req->ctx->compat)
|
|
sr->msg_flags |= MSG_CMSG_COMPAT;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_async_msghdr iomsg, *kmsg;
|
|
struct socket *sock;
|
|
struct io_buffer *kbuf;
|
|
unsigned flags;
|
|
int min_ret = 0;
|
|
int ret, cflags = 0;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
sock = sock_from_file(req->file);
|
|
if (unlikely(!sock))
|
|
return -ENOTSOCK;
|
|
|
|
kmsg = req->async_data;
|
|
if (!kmsg) {
|
|
ret = io_recvmsg_copy_hdr(req, &iomsg);
|
|
if (ret)
|
|
return ret;
|
|
kmsg = &iomsg;
|
|
}
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
kbuf = io_recv_buffer_select(req, !force_nonblock);
|
|
if (IS_ERR(kbuf))
|
|
return PTR_ERR(kbuf);
|
|
kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
|
|
kmsg->fast_iov[0].iov_len = req->sr_msg.len;
|
|
iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
|
|
1, req->sr_msg.len);
|
|
}
|
|
|
|
flags = req->sr_msg.msg_flags;
|
|
if (force_nonblock)
|
|
flags |= MSG_DONTWAIT;
|
|
if (flags & MSG_WAITALL)
|
|
min_ret = iov_iter_count(&kmsg->msg.msg_iter);
|
|
|
|
ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
|
|
kmsg->uaddr, flags);
|
|
if (force_nonblock && ret == -EAGAIN)
|
|
return io_setup_async_msg(req, kmsg);
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
cflags = io_put_recv_kbuf(req);
|
|
/* fast path, check for non-NULL to avoid function call */
|
|
if (kmsg->free_iov)
|
|
kfree(kmsg->free_iov);
|
|
req->flags &= ~REQ_F_NEED_CLEANUP;
|
|
if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, cflags);
|
|
return 0;
|
|
}
|
|
|
|
static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_buffer *kbuf;
|
|
struct io_sr_msg *sr = &req->sr_msg;
|
|
struct msghdr msg;
|
|
void __user *buf = sr->buf;
|
|
struct socket *sock;
|
|
struct iovec iov;
|
|
unsigned flags;
|
|
int min_ret = 0;
|
|
int ret, cflags = 0;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
sock = sock_from_file(req->file);
|
|
if (unlikely(!sock))
|
|
return -ENOTSOCK;
|
|
|
|
if (req->flags & REQ_F_BUFFER_SELECT) {
|
|
kbuf = io_recv_buffer_select(req, !force_nonblock);
|
|
if (IS_ERR(kbuf))
|
|
return PTR_ERR(kbuf);
|
|
buf = u64_to_user_ptr(kbuf->addr);
|
|
}
|
|
|
|
ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
|
|
if (unlikely(ret))
|
|
goto out_free;
|
|
|
|
msg.msg_name = NULL;
|
|
msg.msg_control = NULL;
|
|
msg.msg_controllen = 0;
|
|
msg.msg_namelen = 0;
|
|
msg.msg_iocb = NULL;
|
|
msg.msg_flags = 0;
|
|
|
|
flags = req->sr_msg.msg_flags;
|
|
if (force_nonblock)
|
|
flags |= MSG_DONTWAIT;
|
|
if (flags & MSG_WAITALL)
|
|
min_ret = iov_iter_count(&msg.msg_iter);
|
|
|
|
ret = sock_recvmsg(sock, &msg, flags);
|
|
if (force_nonblock && ret == -EAGAIN)
|
|
return -EAGAIN;
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
out_free:
|
|
if (req->flags & REQ_F_BUFFER_SELECTED)
|
|
cflags = io_put_recv_kbuf(req);
|
|
if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, cflags);
|
|
return 0;
|
|
}
|
|
|
|
static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_accept *accept = &req->accept;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->len || sqe->buf_index)
|
|
return -EINVAL;
|
|
|
|
accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
|
|
accept->flags = READ_ONCE(sqe->accept_flags);
|
|
accept->nofile = rlimit(RLIMIT_NOFILE);
|
|
return 0;
|
|
}
|
|
|
|
static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_accept *accept = &req->accept;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
|
|
int ret;
|
|
|
|
if (req->file->f_flags & O_NONBLOCK)
|
|
req->flags |= REQ_F_NOWAIT;
|
|
|
|
ret = __sys_accept4_file(req->file, file_flags, accept->addr,
|
|
accept->addr_len, accept->flags,
|
|
accept->nofile);
|
|
if (ret == -EAGAIN && force_nonblock)
|
|
return -EAGAIN;
|
|
if (ret < 0) {
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
req_set_fail(req);
|
|
}
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_connect_prep_async(struct io_kiocb *req)
|
|
{
|
|
struct io_async_connect *io = req->async_data;
|
|
struct io_connect *conn = &req->connect;
|
|
|
|
return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
|
|
}
|
|
|
|
static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_connect *conn = &req->connect;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
|
|
return -EINVAL;
|
|
|
|
conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
|
|
conn->addr_len = READ_ONCE(sqe->addr2);
|
|
return 0;
|
|
}
|
|
|
|
static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_async_connect __io, *io;
|
|
unsigned file_flags;
|
|
int ret;
|
|
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
|
|
|
|
if (req->async_data) {
|
|
io = req->async_data;
|
|
} else {
|
|
ret = move_addr_to_kernel(req->connect.addr,
|
|
req->connect.addr_len,
|
|
&__io.address);
|
|
if (ret)
|
|
goto out;
|
|
io = &__io;
|
|
}
|
|
|
|
file_flags = force_nonblock ? O_NONBLOCK : 0;
|
|
|
|
ret = __sys_connect_file(req->file, &io->address,
|
|
req->connect.addr_len, file_flags);
|
|
if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
|
|
if (req->async_data)
|
|
return -EAGAIN;
|
|
if (io_alloc_async_data(req)) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
memcpy(req->async_data, &__io, sizeof(__io));
|
|
return -EAGAIN;
|
|
}
|
|
if (ret == -ERESTARTSYS)
|
|
ret = -EINTR;
|
|
out:
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
#else /* !CONFIG_NET */
|
|
#define IO_NETOP_FN(op) \
|
|
static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
|
|
{ \
|
|
return -EOPNOTSUPP; \
|
|
}
|
|
|
|
#define IO_NETOP_PREP(op) \
|
|
IO_NETOP_FN(op) \
|
|
static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
|
|
{ \
|
|
return -EOPNOTSUPP; \
|
|
} \
|
|
|
|
#define IO_NETOP_PREP_ASYNC(op) \
|
|
IO_NETOP_PREP(op) \
|
|
static int io_##op##_prep_async(struct io_kiocb *req) \
|
|
{ \
|
|
return -EOPNOTSUPP; \
|
|
}
|
|
|
|
IO_NETOP_PREP_ASYNC(sendmsg);
|
|
IO_NETOP_PREP_ASYNC(recvmsg);
|
|
IO_NETOP_PREP_ASYNC(connect);
|
|
IO_NETOP_PREP(accept);
|
|
IO_NETOP_FN(send);
|
|
IO_NETOP_FN(recv);
|
|
#endif /* CONFIG_NET */
|
|
|
|
struct io_poll_table {
|
|
struct poll_table_struct pt;
|
|
struct io_kiocb *req;
|
|
int error;
|
|
};
|
|
|
|
static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
|
|
__poll_t mask, io_req_tw_func_t func)
|
|
{
|
|
/* for instances that support it check for an event match first: */
|
|
if (mask && !(mask & poll->events))
|
|
return 0;
|
|
|
|
trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
|
|
|
|
list_del_init(&poll->wait.entry);
|
|
|
|
req->result = mask;
|
|
req->io_task_work.func = func;
|
|
|
|
/*
|
|
* If this fails, then the task is exiting. When a task exits, the
|
|
* work gets canceled, so just cancel this request as well instead
|
|
* of executing it. We can't safely execute it anyway, as we may not
|
|
* have the needed state needed for it anyway.
|
|
*/
|
|
io_req_task_work_add(req);
|
|
return 1;
|
|
}
|
|
|
|
static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
|
|
__acquires(&req->ctx->completion_lock)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
if (unlikely(req->task->flags & PF_EXITING))
|
|
WRITE_ONCE(poll->canceled, true);
|
|
|
|
if (!req->result && !READ_ONCE(poll->canceled)) {
|
|
struct poll_table_struct pt = { ._key = poll->events };
|
|
|
|
req->result = vfs_poll(req->file, &pt) & poll->events;
|
|
}
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
if (!req->result && !READ_ONCE(poll->canceled)) {
|
|
add_wait_queue(poll->head, &poll->wait);
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
|
|
{
|
|
/* pure poll stashes this in ->async_data, poll driven retry elsewhere */
|
|
if (req->opcode == IORING_OP_POLL_ADD)
|
|
return req->async_data;
|
|
return req->apoll->double_poll;
|
|
}
|
|
|
|
static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
|
|
{
|
|
if (req->opcode == IORING_OP_POLL_ADD)
|
|
return &req->poll;
|
|
return &req->apoll->poll;
|
|
}
|
|
|
|
static void io_poll_remove_double(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
struct io_poll_iocb *poll = io_poll_get_double(req);
|
|
|
|
lockdep_assert_held(&req->ctx->completion_lock);
|
|
|
|
if (poll && poll->head) {
|
|
struct wait_queue_head *head = poll->head;
|
|
|
|
spin_lock(&head->lock);
|
|
list_del_init(&poll->wait.entry);
|
|
if (poll->wait.private)
|
|
req_ref_put(req);
|
|
poll->head = NULL;
|
|
spin_unlock(&head->lock);
|
|
}
|
|
}
|
|
|
|
static bool io_poll_complete(struct io_kiocb *req, __poll_t mask)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
unsigned flags = IORING_CQE_F_MORE;
|
|
int error;
|
|
|
|
if (READ_ONCE(req->poll.canceled)) {
|
|
error = -ECANCELED;
|
|
req->poll.events |= EPOLLONESHOT;
|
|
} else {
|
|
error = mangle_poll(mask);
|
|
}
|
|
if (req->poll.events & EPOLLONESHOT)
|
|
flags = 0;
|
|
if (!io_cqring_fill_event(ctx, req->user_data, error, flags)) {
|
|
io_poll_remove_waitqs(req);
|
|
req->poll.done = true;
|
|
flags = 0;
|
|
}
|
|
if (flags & IORING_CQE_F_MORE)
|
|
ctx->cq_extra++;
|
|
|
|
io_commit_cqring(ctx);
|
|
return !(flags & IORING_CQE_F_MORE);
|
|
}
|
|
|
|
static void io_poll_task_func(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_kiocb *nxt;
|
|
|
|
if (io_poll_rewait(req, &req->poll)) {
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
} else {
|
|
bool done;
|
|
|
|
done = io_poll_complete(req, req->result);
|
|
if (done) {
|
|
hash_del(&req->hash_node);
|
|
} else {
|
|
req->result = 0;
|
|
add_wait_queue(req->poll.head, &req->poll.wait);
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
io_cqring_ev_posted(ctx);
|
|
|
|
if (done) {
|
|
nxt = io_put_req_find_next(req);
|
|
if (nxt)
|
|
io_req_task_submit(nxt);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
|
|
int sync, void *key)
|
|
{
|
|
struct io_kiocb *req = wait->private;
|
|
struct io_poll_iocb *poll = io_poll_get_single(req);
|
|
__poll_t mask = key_to_poll(key);
|
|
|
|
/* for instances that support it check for an event match first: */
|
|
if (mask && !(mask & poll->events))
|
|
return 0;
|
|
if (!(poll->events & EPOLLONESHOT))
|
|
return poll->wait.func(&poll->wait, mode, sync, key);
|
|
|
|
list_del_init(&wait->entry);
|
|
|
|
if (poll->head) {
|
|
bool done;
|
|
|
|
spin_lock(&poll->head->lock);
|
|
done = list_empty(&poll->wait.entry);
|
|
if (!done)
|
|
list_del_init(&poll->wait.entry);
|
|
/* make sure double remove sees this as being gone */
|
|
wait->private = NULL;
|
|
spin_unlock(&poll->head->lock);
|
|
if (!done) {
|
|
/* use wait func handler, so it matches the rq type */
|
|
poll->wait.func(&poll->wait, mode, sync, key);
|
|
}
|
|
}
|
|
req_ref_put(req);
|
|
return 1;
|
|
}
|
|
|
|
static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
|
|
wait_queue_func_t wake_func)
|
|
{
|
|
poll->head = NULL;
|
|
poll->done = false;
|
|
poll->canceled = false;
|
|
#define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
|
|
/* mask in events that we always want/need */
|
|
poll->events = events | IO_POLL_UNMASK;
|
|
INIT_LIST_HEAD(&poll->wait.entry);
|
|
init_waitqueue_func_entry(&poll->wait, wake_func);
|
|
}
|
|
|
|
static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
|
|
struct wait_queue_head *head,
|
|
struct io_poll_iocb **poll_ptr)
|
|
{
|
|
struct io_kiocb *req = pt->req;
|
|
|
|
/*
|
|
* If poll->head is already set, it's because the file being polled
|
|
* uses multiple waitqueues for poll handling (eg one for read, one
|
|
* for write). Setup a separate io_poll_iocb if this happens.
|
|
*/
|
|
if (unlikely(poll->head)) {
|
|
struct io_poll_iocb *poll_one = poll;
|
|
|
|
/* already have a 2nd entry, fail a third attempt */
|
|
if (*poll_ptr) {
|
|
pt->error = -EINVAL;
|
|
return;
|
|
}
|
|
/*
|
|
* Can't handle multishot for double wait for now, turn it
|
|
* into one-shot mode.
|
|
*/
|
|
if (!(poll_one->events & EPOLLONESHOT))
|
|
poll_one->events |= EPOLLONESHOT;
|
|
/* double add on the same waitqueue head, ignore */
|
|
if (poll_one->head == head)
|
|
return;
|
|
poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
|
|
if (!poll) {
|
|
pt->error = -ENOMEM;
|
|
return;
|
|
}
|
|
io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
|
|
req_ref_get(req);
|
|
poll->wait.private = req;
|
|
*poll_ptr = poll;
|
|
}
|
|
|
|
pt->error = 0;
|
|
poll->head = head;
|
|
|
|
if (poll->events & EPOLLEXCLUSIVE)
|
|
add_wait_queue_exclusive(head, &poll->wait);
|
|
else
|
|
add_wait_queue(head, &poll->wait);
|
|
}
|
|
|
|
static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
|
|
struct poll_table_struct *p)
|
|
{
|
|
struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
|
|
struct async_poll *apoll = pt->req->apoll;
|
|
|
|
__io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
|
|
}
|
|
|
|
static void io_async_task_func(struct io_kiocb *req)
|
|
{
|
|
struct async_poll *apoll = req->apoll;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
trace_io_uring_task_run(req->ctx, req, req->opcode, req->user_data);
|
|
|
|
if (io_poll_rewait(req, &apoll->poll)) {
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
return;
|
|
}
|
|
|
|
hash_del(&req->hash_node);
|
|
io_poll_remove_double(req);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
if (!READ_ONCE(apoll->poll.canceled))
|
|
io_req_task_submit(req);
|
|
else
|
|
io_req_complete_failed(req, -ECANCELED);
|
|
}
|
|
|
|
static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
|
|
void *key)
|
|
{
|
|
struct io_kiocb *req = wait->private;
|
|
struct io_poll_iocb *poll = &req->apoll->poll;
|
|
|
|
trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
|
|
key_to_poll(key));
|
|
|
|
return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
|
|
}
|
|
|
|
static void io_poll_req_insert(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct hlist_head *list;
|
|
|
|
list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
|
|
hlist_add_head(&req->hash_node, list);
|
|
}
|
|
|
|
static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
|
|
struct io_poll_iocb *poll,
|
|
struct io_poll_table *ipt, __poll_t mask,
|
|
wait_queue_func_t wake_func)
|
|
__acquires(&ctx->completion_lock)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
bool cancel = false;
|
|
|
|
INIT_HLIST_NODE(&req->hash_node);
|
|
io_init_poll_iocb(poll, mask, wake_func);
|
|
poll->file = req->file;
|
|
poll->wait.private = req;
|
|
|
|
ipt->pt._key = mask;
|
|
ipt->req = req;
|
|
ipt->error = -EINVAL;
|
|
|
|
mask = vfs_poll(req->file, &ipt->pt) & poll->events;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
if (likely(poll->head)) {
|
|
spin_lock(&poll->head->lock);
|
|
if (unlikely(list_empty(&poll->wait.entry))) {
|
|
if (ipt->error)
|
|
cancel = true;
|
|
ipt->error = 0;
|
|
mask = 0;
|
|
}
|
|
if ((mask && (poll->events & EPOLLONESHOT)) || ipt->error)
|
|
list_del_init(&poll->wait.entry);
|
|
else if (cancel)
|
|
WRITE_ONCE(poll->canceled, true);
|
|
else if (!poll->done) /* actually waiting for an event */
|
|
io_poll_req_insert(req);
|
|
spin_unlock(&poll->head->lock);
|
|
}
|
|
|
|
return mask;
|
|
}
|
|
|
|
enum {
|
|
IO_APOLL_OK,
|
|
IO_APOLL_ABORTED,
|
|
IO_APOLL_READY
|
|
};
|
|
|
|
static int io_arm_poll_handler(struct io_kiocb *req)
|
|
{
|
|
const struct io_op_def *def = &io_op_defs[req->opcode];
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct async_poll *apoll;
|
|
struct io_poll_table ipt;
|
|
__poll_t ret, mask = EPOLLONESHOT | POLLERR | POLLPRI;
|
|
int rw;
|
|
|
|
if (!req->file || !file_can_poll(req->file))
|
|
return IO_APOLL_ABORTED;
|
|
if (req->flags & REQ_F_POLLED)
|
|
return IO_APOLL_ABORTED;
|
|
if (!def->pollin && !def->pollout)
|
|
return IO_APOLL_ABORTED;
|
|
|
|
if (def->pollin) {
|
|
rw = READ;
|
|
mask |= POLLIN | POLLRDNORM;
|
|
|
|
/* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
|
|
if ((req->opcode == IORING_OP_RECVMSG) &&
|
|
(req->sr_msg.msg_flags & MSG_ERRQUEUE))
|
|
mask &= ~POLLIN;
|
|
} else {
|
|
rw = WRITE;
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
}
|
|
|
|
/* if we can't nonblock try, then no point in arming a poll handler */
|
|
if (!io_file_supports_async(req, rw))
|
|
return IO_APOLL_ABORTED;
|
|
|
|
apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
|
|
if (unlikely(!apoll))
|
|
return IO_APOLL_ABORTED;
|
|
apoll->double_poll = NULL;
|
|
req->apoll = apoll;
|
|
req->flags |= REQ_F_POLLED;
|
|
ipt.pt._qproc = io_async_queue_proc;
|
|
|
|
ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
|
|
io_async_wake);
|
|
if (ret || ipt.error) {
|
|
io_poll_remove_double(req);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
if (ret)
|
|
return IO_APOLL_READY;
|
|
return IO_APOLL_ABORTED;
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
|
|
mask, apoll->poll.events);
|
|
return IO_APOLL_OK;
|
|
}
|
|
|
|
static bool __io_poll_remove_one(struct io_kiocb *req,
|
|
struct io_poll_iocb *poll, bool do_cancel)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
bool do_complete = false;
|
|
|
|
if (!poll->head)
|
|
return false;
|
|
spin_lock(&poll->head->lock);
|
|
if (do_cancel)
|
|
WRITE_ONCE(poll->canceled, true);
|
|
if (!list_empty(&poll->wait.entry)) {
|
|
list_del_init(&poll->wait.entry);
|
|
do_complete = true;
|
|
}
|
|
spin_unlock(&poll->head->lock);
|
|
hash_del(&req->hash_node);
|
|
return do_complete;
|
|
}
|
|
|
|
static bool io_poll_remove_waitqs(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
bool do_complete;
|
|
|
|
io_poll_remove_double(req);
|
|
do_complete = __io_poll_remove_one(req, io_poll_get_single(req), true);
|
|
|
|
if (req->opcode != IORING_OP_POLL_ADD && do_complete) {
|
|
/* non-poll requests have submit ref still */
|
|
req_ref_put(req);
|
|
}
|
|
return do_complete;
|
|
}
|
|
|
|
static bool io_poll_remove_one(struct io_kiocb *req)
|
|
__must_hold(&req->ctx->completion_lock)
|
|
{
|
|
bool do_complete;
|
|
|
|
do_complete = io_poll_remove_waitqs(req);
|
|
if (do_complete) {
|
|
io_cqring_fill_event(req->ctx, req->user_data, -ECANCELED, 0);
|
|
io_commit_cqring(req->ctx);
|
|
req_set_fail(req);
|
|
io_put_req_deferred(req, 1);
|
|
}
|
|
|
|
return do_complete;
|
|
}
|
|
|
|
/*
|
|
* Returns true if we found and killed one or more poll requests
|
|
*/
|
|
static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
|
|
bool cancel_all)
|
|
{
|
|
struct hlist_node *tmp;
|
|
struct io_kiocb *req;
|
|
int posted = 0, i;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
|
|
struct hlist_head *list;
|
|
|
|
list = &ctx->cancel_hash[i];
|
|
hlist_for_each_entry_safe(req, tmp, list, hash_node) {
|
|
if (io_match_task(req, tsk, cancel_all))
|
|
posted += io_poll_remove_one(req);
|
|
}
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
if (posted)
|
|
io_cqring_ev_posted(ctx);
|
|
|
|
return posted != 0;
|
|
}
|
|
|
|
static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
|
|
bool poll_only)
|
|
__must_hold(&ctx->completion_lock)
|
|
{
|
|
struct hlist_head *list;
|
|
struct io_kiocb *req;
|
|
|
|
list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
|
|
hlist_for_each_entry(req, list, hash_node) {
|
|
if (sqe_addr != req->user_data)
|
|
continue;
|
|
if (poll_only && req->opcode != IORING_OP_POLL_ADD)
|
|
continue;
|
|
return req;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
|
|
bool poll_only)
|
|
__must_hold(&ctx->completion_lock)
|
|
{
|
|
struct io_kiocb *req;
|
|
|
|
req = io_poll_find(ctx, sqe_addr, poll_only);
|
|
if (!req)
|
|
return -ENOENT;
|
|
if (io_poll_remove_one(req))
|
|
return 0;
|
|
|
|
return -EALREADY;
|
|
}
|
|
|
|
static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
|
|
unsigned int flags)
|
|
{
|
|
u32 events;
|
|
|
|
events = READ_ONCE(sqe->poll32_events);
|
|
#ifdef __BIG_ENDIAN
|
|
events = swahw32(events);
|
|
#endif
|
|
if (!(flags & IORING_POLL_ADD_MULTI))
|
|
events |= EPOLLONESHOT;
|
|
return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
|
|
}
|
|
|
|
static int io_poll_update_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_poll_update *upd = &req->poll_update;
|
|
u32 flags;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index)
|
|
return -EINVAL;
|
|
flags = READ_ONCE(sqe->len);
|
|
if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
|
|
IORING_POLL_ADD_MULTI))
|
|
return -EINVAL;
|
|
/* meaningless without update */
|
|
if (flags == IORING_POLL_ADD_MULTI)
|
|
return -EINVAL;
|
|
|
|
upd->old_user_data = READ_ONCE(sqe->addr);
|
|
upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
|
|
upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
|
|
|
|
upd->new_user_data = READ_ONCE(sqe->off);
|
|
if (!upd->update_user_data && upd->new_user_data)
|
|
return -EINVAL;
|
|
if (upd->update_events)
|
|
upd->events = io_poll_parse_events(sqe, flags);
|
|
else if (sqe->poll32_events)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
|
|
void *key)
|
|
{
|
|
struct io_kiocb *req = wait->private;
|
|
struct io_poll_iocb *poll = &req->poll;
|
|
|
|
return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
|
|
}
|
|
|
|
static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
|
|
struct poll_table_struct *p)
|
|
{
|
|
struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
|
|
|
|
__io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
|
|
}
|
|
|
|
static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_poll_iocb *poll = &req->poll;
|
|
u32 flags;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
|
|
return -EINVAL;
|
|
flags = READ_ONCE(sqe->len);
|
|
if (flags & ~IORING_POLL_ADD_MULTI)
|
|
return -EINVAL;
|
|
|
|
poll->events = io_poll_parse_events(sqe, flags);
|
|
return 0;
|
|
}
|
|
|
|
static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_poll_iocb *poll = &req->poll;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_poll_table ipt;
|
|
__poll_t mask;
|
|
|
|
ipt.pt._qproc = io_poll_queue_proc;
|
|
|
|
mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
|
|
io_poll_wake);
|
|
|
|
if (mask) { /* no async, we'd stolen it */
|
|
ipt.error = 0;
|
|
io_poll_complete(req, mask);
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
if (mask) {
|
|
io_cqring_ev_posted(ctx);
|
|
if (poll->events & EPOLLONESHOT)
|
|
io_put_req(req);
|
|
}
|
|
return ipt.error;
|
|
}
|
|
|
|
static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_kiocb *preq;
|
|
bool completing;
|
|
int ret;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
|
|
if (!preq) {
|
|
ret = -ENOENT;
|
|
goto err;
|
|
}
|
|
|
|
if (!req->poll_update.update_events && !req->poll_update.update_user_data) {
|
|
completing = true;
|
|
ret = io_poll_remove_one(preq) ? 0 : -EALREADY;
|
|
goto err;
|
|
}
|
|
|
|
/*
|
|
* Don't allow racy completion with singleshot, as we cannot safely
|
|
* update those. For multishot, if we're racing with completion, just
|
|
* let completion re-add it.
|
|
*/
|
|
completing = !__io_poll_remove_one(preq, &preq->poll, false);
|
|
if (completing && (preq->poll.events & EPOLLONESHOT)) {
|
|
ret = -EALREADY;
|
|
goto err;
|
|
}
|
|
/* we now have a detached poll request. reissue. */
|
|
ret = 0;
|
|
err:
|
|
if (ret < 0) {
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
req_set_fail(req);
|
|
io_req_complete(req, ret);
|
|
return 0;
|
|
}
|
|
/* only mask one event flags, keep behavior flags */
|
|
if (req->poll_update.update_events) {
|
|
preq->poll.events &= ~0xffff;
|
|
preq->poll.events |= req->poll_update.events & 0xffff;
|
|
preq->poll.events |= IO_POLL_UNMASK;
|
|
}
|
|
if (req->poll_update.update_user_data)
|
|
preq->user_data = req->poll_update.new_user_data;
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
/* complete update request, we're done with it */
|
|
io_req_complete(req, ret);
|
|
|
|
if (!completing) {
|
|
ret = io_poll_add(preq, issue_flags);
|
|
if (ret < 0) {
|
|
req_set_fail(preq);
|
|
io_req_complete(preq, ret);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
|
|
{
|
|
struct io_timeout_data *data = container_of(timer,
|
|
struct io_timeout_data, timer);
|
|
struct io_kiocb *req = data->req;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
list_del_init(&req->timeout.list);
|
|
atomic_set(&req->ctx->cq_timeouts,
|
|
atomic_read(&req->ctx->cq_timeouts) + 1);
|
|
|
|
io_cqring_fill_event(ctx, req->user_data, -ETIME, 0);
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
|
|
io_cqring_ev_posted(ctx);
|
|
req_set_fail(req);
|
|
io_put_req(req);
|
|
return HRTIMER_NORESTART;
|
|
}
|
|
|
|
static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
|
|
__u64 user_data)
|
|
__must_hold(&ctx->completion_lock)
|
|
{
|
|
struct io_timeout_data *io;
|
|
struct io_kiocb *req;
|
|
bool found = false;
|
|
|
|
list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
|
|
found = user_data == req->user_data;
|
|
if (found)
|
|
break;
|
|
}
|
|
if (!found)
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
io = req->async_data;
|
|
if (hrtimer_try_to_cancel(&io->timer) == -1)
|
|
return ERR_PTR(-EALREADY);
|
|
list_del_init(&req->timeout.list);
|
|
return req;
|
|
}
|
|
|
|
static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
|
|
__must_hold(&ctx->completion_lock)
|
|
{
|
|
struct io_kiocb *req = io_timeout_extract(ctx, user_data);
|
|
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
req_set_fail(req);
|
|
io_cqring_fill_event(ctx, req->user_data, -ECANCELED, 0);
|
|
io_put_req_deferred(req, 1);
|
|
return 0;
|
|
}
|
|
|
|
static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
|
|
struct timespec64 *ts, enum hrtimer_mode mode)
|
|
__must_hold(&ctx->completion_lock)
|
|
{
|
|
struct io_kiocb *req = io_timeout_extract(ctx, user_data);
|
|
struct io_timeout_data *data;
|
|
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
req->timeout.off = 0; /* noseq */
|
|
data = req->async_data;
|
|
list_add_tail(&req->timeout.list, &ctx->timeout_list);
|
|
hrtimer_init(&data->timer, CLOCK_MONOTONIC, mode);
|
|
data->timer.function = io_timeout_fn;
|
|
hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
|
|
return 0;
|
|
}
|
|
|
|
static int io_timeout_remove_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_timeout_rem *tr = &req->timeout_rem;
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index || sqe->len)
|
|
return -EINVAL;
|
|
|
|
tr->addr = READ_ONCE(sqe->addr);
|
|
tr->flags = READ_ONCE(sqe->timeout_flags);
|
|
if (tr->flags & IORING_TIMEOUT_UPDATE) {
|
|
if (tr->flags & ~(IORING_TIMEOUT_UPDATE|IORING_TIMEOUT_ABS))
|
|
return -EINVAL;
|
|
if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
|
|
return -EFAULT;
|
|
} else if (tr->flags) {
|
|
/* timeout removal doesn't support flags */
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
|
|
{
|
|
return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
|
|
: HRTIMER_MODE_REL;
|
|
}
|
|
|
|
/*
|
|
* Remove or update an existing timeout command
|
|
*/
|
|
static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_timeout_rem *tr = &req->timeout_rem;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
int ret;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE))
|
|
ret = io_timeout_cancel(ctx, tr->addr);
|
|
else
|
|
ret = io_timeout_update(ctx, tr->addr, &tr->ts,
|
|
io_translate_timeout_mode(tr->flags));
|
|
|
|
io_cqring_fill_event(ctx, req->user_data, ret, 0);
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
io_cqring_ev_posted(ctx);
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_put_req(req);
|
|
return 0;
|
|
}
|
|
|
|
static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
|
|
bool is_timeout_link)
|
|
{
|
|
struct io_timeout_data *data;
|
|
unsigned flags;
|
|
u32 off = READ_ONCE(sqe->off);
|
|
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->buf_index || sqe->len != 1)
|
|
return -EINVAL;
|
|
if (off && is_timeout_link)
|
|
return -EINVAL;
|
|
flags = READ_ONCE(sqe->timeout_flags);
|
|
if (flags & ~IORING_TIMEOUT_ABS)
|
|
return -EINVAL;
|
|
|
|
req->timeout.off = off;
|
|
if (unlikely(off && !req->ctx->off_timeout_used))
|
|
req->ctx->off_timeout_used = true;
|
|
|
|
if (!req->async_data && io_alloc_async_data(req))
|
|
return -ENOMEM;
|
|
|
|
data = req->async_data;
|
|
data->req = req;
|
|
|
|
if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
|
|
return -EFAULT;
|
|
|
|
data->mode = io_translate_timeout_mode(flags);
|
|
hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
|
|
if (is_timeout_link)
|
|
io_req_track_inflight(req);
|
|
return 0;
|
|
}
|
|
|
|
static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_timeout_data *data = req->async_data;
|
|
struct list_head *entry;
|
|
u32 tail, off = req->timeout.off;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
|
|
/*
|
|
* sqe->off holds how many events that need to occur for this
|
|
* timeout event to be satisfied. If it isn't set, then this is
|
|
* a pure timeout request, sequence isn't used.
|
|
*/
|
|
if (io_is_timeout_noseq(req)) {
|
|
entry = ctx->timeout_list.prev;
|
|
goto add;
|
|
}
|
|
|
|
tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
|
|
req->timeout.target_seq = tail + off;
|
|
|
|
/* Update the last seq here in case io_flush_timeouts() hasn't.
|
|
* This is safe because ->completion_lock is held, and submissions
|
|
* and completions are never mixed in the same ->completion_lock section.
|
|
*/
|
|
ctx->cq_last_tm_flush = tail;
|
|
|
|
/*
|
|
* Insertion sort, ensuring the first entry in the list is always
|
|
* the one we need first.
|
|
*/
|
|
list_for_each_prev(entry, &ctx->timeout_list) {
|
|
struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
|
|
timeout.list);
|
|
|
|
if (io_is_timeout_noseq(nxt))
|
|
continue;
|
|
/* nxt.seq is behind @tail, otherwise would've been completed */
|
|
if (off >= nxt->timeout.target_seq - tail)
|
|
break;
|
|
}
|
|
add:
|
|
list_add(&req->timeout.list, entry);
|
|
data->timer.function = io_timeout_fn;
|
|
hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
return 0;
|
|
}
|
|
|
|
struct io_cancel_data {
|
|
struct io_ring_ctx *ctx;
|
|
u64 user_data;
|
|
};
|
|
|
|
static bool io_cancel_cb(struct io_wq_work *work, void *data)
|
|
{
|
|
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
|
|
struct io_cancel_data *cd = data;
|
|
|
|
return req->ctx == cd->ctx && req->user_data == cd->user_data;
|
|
}
|
|
|
|
static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
|
|
struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
|
|
enum io_wq_cancel cancel_ret;
|
|
int ret = 0;
|
|
|
|
if (!tctx || !tctx->io_wq)
|
|
return -ENOENT;
|
|
|
|
cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
|
|
switch (cancel_ret) {
|
|
case IO_WQ_CANCEL_OK:
|
|
ret = 0;
|
|
break;
|
|
case IO_WQ_CANCEL_RUNNING:
|
|
ret = -EALREADY;
|
|
break;
|
|
case IO_WQ_CANCEL_NOTFOUND:
|
|
ret = -ENOENT;
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
|
|
struct io_kiocb *req, __u64 sqe_addr,
|
|
int success_ret)
|
|
{
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
if (ret != -ENOENT)
|
|
goto done;
|
|
ret = io_timeout_cancel(ctx, sqe_addr);
|
|
if (ret != -ENOENT)
|
|
goto done;
|
|
ret = io_poll_cancel(ctx, sqe_addr, false);
|
|
done:
|
|
if (!ret)
|
|
ret = success_ret;
|
|
io_cqring_fill_event(ctx, req->user_data, ret, 0);
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
io_cqring_ev_posted(ctx);
|
|
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
}
|
|
|
|
static int io_async_cancel_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
|
|
return -EINVAL;
|
|
if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags)
|
|
return -EINVAL;
|
|
|
|
req->cancel.addr = READ_ONCE(sqe->addr);
|
|
return 0;
|
|
}
|
|
|
|
static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
u64 sqe_addr = req->cancel.addr;
|
|
struct io_tctx_node *node;
|
|
int ret;
|
|
|
|
/* tasks should wait for their io-wq threads, so safe w/o sync */
|
|
ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
if (ret != -ENOENT)
|
|
goto done;
|
|
ret = io_timeout_cancel(ctx, sqe_addr);
|
|
if (ret != -ENOENT)
|
|
goto done;
|
|
ret = io_poll_cancel(ctx, sqe_addr, false);
|
|
if (ret != -ENOENT)
|
|
goto done;
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
/* slow path, try all io-wq's */
|
|
io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
|
|
ret = -ENOENT;
|
|
list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
|
|
struct io_uring_task *tctx = node->task->io_uring;
|
|
|
|
ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
|
|
if (ret != -ENOENT)
|
|
break;
|
|
}
|
|
io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
done:
|
|
io_cqring_fill_event(ctx, req->user_data, ret, 0);
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
io_cqring_ev_posted(ctx);
|
|
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
io_put_req(req);
|
|
return 0;
|
|
}
|
|
|
|
static int io_rsrc_update_prep(struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
|
|
return -EINVAL;
|
|
if (sqe->ioprio || sqe->rw_flags)
|
|
return -EINVAL;
|
|
|
|
req->rsrc_update.offset = READ_ONCE(sqe->off);
|
|
req->rsrc_update.nr_args = READ_ONCE(sqe->len);
|
|
if (!req->rsrc_update.nr_args)
|
|
return -EINVAL;
|
|
req->rsrc_update.arg = READ_ONCE(sqe->addr);
|
|
return 0;
|
|
}
|
|
|
|
static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_uring_rsrc_update2 up;
|
|
int ret;
|
|
|
|
if (issue_flags & IO_URING_F_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
up.offset = req->rsrc_update.offset;
|
|
up.data = req->rsrc_update.arg;
|
|
up.nr = 0;
|
|
up.tags = 0;
|
|
up.resv = 0;
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
|
|
&up, req->rsrc_update.nr_args);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
|
|
if (ret < 0)
|
|
req_set_fail(req);
|
|
__io_req_complete(req, issue_flags, ret, 0);
|
|
return 0;
|
|
}
|
|
|
|
static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
|
|
{
|
|
switch (req->opcode) {
|
|
case IORING_OP_NOP:
|
|
return 0;
|
|
case IORING_OP_READV:
|
|
case IORING_OP_READ_FIXED:
|
|
case IORING_OP_READ:
|
|
return io_read_prep(req, sqe);
|
|
case IORING_OP_WRITEV:
|
|
case IORING_OP_WRITE_FIXED:
|
|
case IORING_OP_WRITE:
|
|
return io_write_prep(req, sqe);
|
|
case IORING_OP_POLL_ADD:
|
|
return io_poll_add_prep(req, sqe);
|
|
case IORING_OP_POLL_REMOVE:
|
|
return io_poll_update_prep(req, sqe);
|
|
case IORING_OP_FSYNC:
|
|
return io_fsync_prep(req, sqe);
|
|
case IORING_OP_SYNC_FILE_RANGE:
|
|
return io_sfr_prep(req, sqe);
|
|
case IORING_OP_SENDMSG:
|
|
case IORING_OP_SEND:
|
|
return io_sendmsg_prep(req, sqe);
|
|
case IORING_OP_RECVMSG:
|
|
case IORING_OP_RECV:
|
|
return io_recvmsg_prep(req, sqe);
|
|
case IORING_OP_CONNECT:
|
|
return io_connect_prep(req, sqe);
|
|
case IORING_OP_TIMEOUT:
|
|
return io_timeout_prep(req, sqe, false);
|
|
case IORING_OP_TIMEOUT_REMOVE:
|
|
return io_timeout_remove_prep(req, sqe);
|
|
case IORING_OP_ASYNC_CANCEL:
|
|
return io_async_cancel_prep(req, sqe);
|
|
case IORING_OP_LINK_TIMEOUT:
|
|
return io_timeout_prep(req, sqe, true);
|
|
case IORING_OP_ACCEPT:
|
|
return io_accept_prep(req, sqe);
|
|
case IORING_OP_FALLOCATE:
|
|
return io_fallocate_prep(req, sqe);
|
|
case IORING_OP_OPENAT:
|
|
return io_openat_prep(req, sqe);
|
|
case IORING_OP_CLOSE:
|
|
return io_close_prep(req, sqe);
|
|
case IORING_OP_FILES_UPDATE:
|
|
return io_rsrc_update_prep(req, sqe);
|
|
case IORING_OP_STATX:
|
|
return io_statx_prep(req, sqe);
|
|
case IORING_OP_FADVISE:
|
|
return io_fadvise_prep(req, sqe);
|
|
case IORING_OP_MADVISE:
|
|
return io_madvise_prep(req, sqe);
|
|
case IORING_OP_OPENAT2:
|
|
return io_openat2_prep(req, sqe);
|
|
case IORING_OP_EPOLL_CTL:
|
|
return io_epoll_ctl_prep(req, sqe);
|
|
case IORING_OP_SPLICE:
|
|
return io_splice_prep(req, sqe);
|
|
case IORING_OP_PROVIDE_BUFFERS:
|
|
return io_provide_buffers_prep(req, sqe);
|
|
case IORING_OP_REMOVE_BUFFERS:
|
|
return io_remove_buffers_prep(req, sqe);
|
|
case IORING_OP_TEE:
|
|
return io_tee_prep(req, sqe);
|
|
case IORING_OP_SHUTDOWN:
|
|
return io_shutdown_prep(req, sqe);
|
|
case IORING_OP_RENAMEAT:
|
|
return io_renameat_prep(req, sqe);
|
|
case IORING_OP_UNLINKAT:
|
|
return io_unlinkat_prep(req, sqe);
|
|
}
|
|
|
|
printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
|
|
req->opcode);
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int io_req_prep_async(struct io_kiocb *req)
|
|
{
|
|
if (!io_op_defs[req->opcode].needs_async_setup)
|
|
return 0;
|
|
if (WARN_ON_ONCE(req->async_data))
|
|
return -EFAULT;
|
|
if (io_alloc_async_data(req))
|
|
return -EAGAIN;
|
|
|
|
switch (req->opcode) {
|
|
case IORING_OP_READV:
|
|
return io_rw_prep_async(req, READ);
|
|
case IORING_OP_WRITEV:
|
|
return io_rw_prep_async(req, WRITE);
|
|
case IORING_OP_SENDMSG:
|
|
return io_sendmsg_prep_async(req);
|
|
case IORING_OP_RECVMSG:
|
|
return io_recvmsg_prep_async(req);
|
|
case IORING_OP_CONNECT:
|
|
return io_connect_prep_async(req);
|
|
}
|
|
printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
|
|
req->opcode);
|
|
return -EFAULT;
|
|
}
|
|
|
|
static u32 io_get_sequence(struct io_kiocb *req)
|
|
{
|
|
u32 seq = req->ctx->cached_sq_head;
|
|
|
|
/* need original cached_sq_head, but it was increased for each req */
|
|
io_for_each_link(req, req)
|
|
seq--;
|
|
return seq;
|
|
}
|
|
|
|
static bool io_drain_req(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *pos;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_defer_entry *de;
|
|
int ret;
|
|
u32 seq;
|
|
|
|
/*
|
|
* If we need to drain a request in the middle of a link, drain the
|
|
* head request and the next request/link after the current link.
|
|
* Considering sequential execution of links, IOSQE_IO_DRAIN will be
|
|
* maintained for every request of our link.
|
|
*/
|
|
if (ctx->drain_next) {
|
|
req->flags |= REQ_F_IO_DRAIN;
|
|
ctx->drain_next = false;
|
|
}
|
|
/* not interested in head, start from the first linked */
|
|
io_for_each_link(pos, req->link) {
|
|
if (pos->flags & REQ_F_IO_DRAIN) {
|
|
ctx->drain_next = true;
|
|
req->flags |= REQ_F_IO_DRAIN;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Still need defer if there is pending req in defer list. */
|
|
if (likely(list_empty_careful(&ctx->defer_list) &&
|
|
!(req->flags & REQ_F_IO_DRAIN))) {
|
|
ctx->drain_active = false;
|
|
return false;
|
|
}
|
|
|
|
seq = io_get_sequence(req);
|
|
/* Still a chance to pass the sequence check */
|
|
if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
|
|
return false;
|
|
|
|
ret = io_req_prep_async(req);
|
|
if (ret)
|
|
return ret;
|
|
io_prep_async_link(req);
|
|
de = kmalloc(sizeof(*de), GFP_KERNEL);
|
|
if (!de) {
|
|
io_req_complete_failed(req, -ENOMEM);
|
|
return true;
|
|
}
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
kfree(de);
|
|
io_queue_async_work(req);
|
|
return true;
|
|
}
|
|
|
|
trace_io_uring_defer(ctx, req, req->user_data);
|
|
de->req = req;
|
|
de->seq = seq;
|
|
list_add_tail(&de->list, &ctx->defer_list);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
return true;
|
|
}
|
|
|
|
static void io_clean_op(struct io_kiocb *req)
|
|
{
|
|
if (req->flags & REQ_F_BUFFER_SELECTED) {
|
|
switch (req->opcode) {
|
|
case IORING_OP_READV:
|
|
case IORING_OP_READ_FIXED:
|
|
case IORING_OP_READ:
|
|
kfree((void *)(unsigned long)req->rw.addr);
|
|
break;
|
|
case IORING_OP_RECVMSG:
|
|
case IORING_OP_RECV:
|
|
kfree(req->sr_msg.kbuf);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (req->flags & REQ_F_NEED_CLEANUP) {
|
|
switch (req->opcode) {
|
|
case IORING_OP_READV:
|
|
case IORING_OP_READ_FIXED:
|
|
case IORING_OP_READ:
|
|
case IORING_OP_WRITEV:
|
|
case IORING_OP_WRITE_FIXED:
|
|
case IORING_OP_WRITE: {
|
|
struct io_async_rw *io = req->async_data;
|
|
|
|
kfree(io->free_iovec);
|
|
break;
|
|
}
|
|
case IORING_OP_RECVMSG:
|
|
case IORING_OP_SENDMSG: {
|
|
struct io_async_msghdr *io = req->async_data;
|
|
|
|
kfree(io->free_iov);
|
|
break;
|
|
}
|
|
case IORING_OP_SPLICE:
|
|
case IORING_OP_TEE:
|
|
if (!(req->splice.flags & SPLICE_F_FD_IN_FIXED))
|
|
io_put_file(req->splice.file_in);
|
|
break;
|
|
case IORING_OP_OPENAT:
|
|
case IORING_OP_OPENAT2:
|
|
if (req->open.filename)
|
|
putname(req->open.filename);
|
|
break;
|
|
case IORING_OP_RENAMEAT:
|
|
putname(req->rename.oldpath);
|
|
putname(req->rename.newpath);
|
|
break;
|
|
case IORING_OP_UNLINKAT:
|
|
putname(req->unlink.filename);
|
|
break;
|
|
}
|
|
}
|
|
if ((req->flags & REQ_F_POLLED) && req->apoll) {
|
|
kfree(req->apoll->double_poll);
|
|
kfree(req->apoll);
|
|
req->apoll = NULL;
|
|
}
|
|
if (req->flags & REQ_F_INFLIGHT) {
|
|
struct io_uring_task *tctx = req->task->io_uring;
|
|
|
|
atomic_dec(&tctx->inflight_tracked);
|
|
}
|
|
if (req->flags & REQ_F_CREDS)
|
|
put_cred(req->creds);
|
|
|
|
req->flags &= ~IO_REQ_CLEAN_FLAGS;
|
|
}
|
|
|
|
static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
const struct cred *creds = NULL;
|
|
int ret;
|
|
|
|
if ((req->flags & REQ_F_CREDS) && req->creds != current_cred())
|
|
creds = override_creds(req->creds);
|
|
|
|
switch (req->opcode) {
|
|
case IORING_OP_NOP:
|
|
ret = io_nop(req, issue_flags);
|
|
break;
|
|
case IORING_OP_READV:
|
|
case IORING_OP_READ_FIXED:
|
|
case IORING_OP_READ:
|
|
ret = io_read(req, issue_flags);
|
|
break;
|
|
case IORING_OP_WRITEV:
|
|
case IORING_OP_WRITE_FIXED:
|
|
case IORING_OP_WRITE:
|
|
ret = io_write(req, issue_flags);
|
|
break;
|
|
case IORING_OP_FSYNC:
|
|
ret = io_fsync(req, issue_flags);
|
|
break;
|
|
case IORING_OP_POLL_ADD:
|
|
ret = io_poll_add(req, issue_flags);
|
|
break;
|
|
case IORING_OP_POLL_REMOVE:
|
|
ret = io_poll_update(req, issue_flags);
|
|
break;
|
|
case IORING_OP_SYNC_FILE_RANGE:
|
|
ret = io_sync_file_range(req, issue_flags);
|
|
break;
|
|
case IORING_OP_SENDMSG:
|
|
ret = io_sendmsg(req, issue_flags);
|
|
break;
|
|
case IORING_OP_SEND:
|
|
ret = io_send(req, issue_flags);
|
|
break;
|
|
case IORING_OP_RECVMSG:
|
|
ret = io_recvmsg(req, issue_flags);
|
|
break;
|
|
case IORING_OP_RECV:
|
|
ret = io_recv(req, issue_flags);
|
|
break;
|
|
case IORING_OP_TIMEOUT:
|
|
ret = io_timeout(req, issue_flags);
|
|
break;
|
|
case IORING_OP_TIMEOUT_REMOVE:
|
|
ret = io_timeout_remove(req, issue_flags);
|
|
break;
|
|
case IORING_OP_ACCEPT:
|
|
ret = io_accept(req, issue_flags);
|
|
break;
|
|
case IORING_OP_CONNECT:
|
|
ret = io_connect(req, issue_flags);
|
|
break;
|
|
case IORING_OP_ASYNC_CANCEL:
|
|
ret = io_async_cancel(req, issue_flags);
|
|
break;
|
|
case IORING_OP_FALLOCATE:
|
|
ret = io_fallocate(req, issue_flags);
|
|
break;
|
|
case IORING_OP_OPENAT:
|
|
ret = io_openat(req, issue_flags);
|
|
break;
|
|
case IORING_OP_CLOSE:
|
|
ret = io_close(req, issue_flags);
|
|
break;
|
|
case IORING_OP_FILES_UPDATE:
|
|
ret = io_files_update(req, issue_flags);
|
|
break;
|
|
case IORING_OP_STATX:
|
|
ret = io_statx(req, issue_flags);
|
|
break;
|
|
case IORING_OP_FADVISE:
|
|
ret = io_fadvise(req, issue_flags);
|
|
break;
|
|
case IORING_OP_MADVISE:
|
|
ret = io_madvise(req, issue_flags);
|
|
break;
|
|
case IORING_OP_OPENAT2:
|
|
ret = io_openat2(req, issue_flags);
|
|
break;
|
|
case IORING_OP_EPOLL_CTL:
|
|
ret = io_epoll_ctl(req, issue_flags);
|
|
break;
|
|
case IORING_OP_SPLICE:
|
|
ret = io_splice(req, issue_flags);
|
|
break;
|
|
case IORING_OP_PROVIDE_BUFFERS:
|
|
ret = io_provide_buffers(req, issue_flags);
|
|
break;
|
|
case IORING_OP_REMOVE_BUFFERS:
|
|
ret = io_remove_buffers(req, issue_flags);
|
|
break;
|
|
case IORING_OP_TEE:
|
|
ret = io_tee(req, issue_flags);
|
|
break;
|
|
case IORING_OP_SHUTDOWN:
|
|
ret = io_shutdown(req, issue_flags);
|
|
break;
|
|
case IORING_OP_RENAMEAT:
|
|
ret = io_renameat(req, issue_flags);
|
|
break;
|
|
case IORING_OP_UNLINKAT:
|
|
ret = io_unlinkat(req, issue_flags);
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (creds)
|
|
revert_creds(creds);
|
|
if (ret)
|
|
return ret;
|
|
/* If the op doesn't have a file, we're not polling for it */
|
|
if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
|
|
io_iopoll_req_issued(req);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void io_wq_submit_work(struct io_wq_work *work)
|
|
{
|
|
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
|
|
struct io_kiocb *timeout;
|
|
int ret = 0;
|
|
|
|
timeout = io_prep_linked_timeout(req);
|
|
if (timeout)
|
|
io_queue_linked_timeout(timeout);
|
|
|
|
if (work->flags & IO_WQ_WORK_CANCEL)
|
|
ret = -ECANCELED;
|
|
|
|
if (!ret) {
|
|
do {
|
|
ret = io_issue_sqe(req, 0);
|
|
/*
|
|
* We can get EAGAIN for polled IO even though we're
|
|
* forcing a sync submission from here, since we can't
|
|
* wait for request slots on the block side.
|
|
*/
|
|
if (ret != -EAGAIN)
|
|
break;
|
|
cond_resched();
|
|
} while (1);
|
|
}
|
|
|
|
/* avoid locking problems by failing it from a clean context */
|
|
if (ret) {
|
|
/* io-wq is going to take one down */
|
|
req_ref_get(req);
|
|
io_req_task_queue_fail(req, ret);
|
|
}
|
|
}
|
|
|
|
#define FFS_ASYNC_READ 0x1UL
|
|
#define FFS_ASYNC_WRITE 0x2UL
|
|
#ifdef CONFIG_64BIT
|
|
#define FFS_ISREG 0x4UL
|
|
#else
|
|
#define FFS_ISREG 0x0UL
|
|
#endif
|
|
#define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
|
|
|
|
static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
|
|
unsigned i)
|
|
{
|
|
struct io_fixed_file *table_l2;
|
|
|
|
table_l2 = table->files[i >> IORING_FILE_TABLE_SHIFT];
|
|
return &table_l2[i & IORING_FILE_TABLE_MASK];
|
|
}
|
|
|
|
static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
|
|
int index)
|
|
{
|
|
struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
|
|
|
|
return (struct file *) (slot->file_ptr & FFS_MASK);
|
|
}
|
|
|
|
static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
|
|
{
|
|
unsigned long file_ptr = (unsigned long) file;
|
|
|
|
if (__io_file_supports_async(file, READ))
|
|
file_ptr |= FFS_ASYNC_READ;
|
|
if (__io_file_supports_async(file, WRITE))
|
|
file_ptr |= FFS_ASYNC_WRITE;
|
|
if (S_ISREG(file_inode(file)->i_mode))
|
|
file_ptr |= FFS_ISREG;
|
|
file_slot->file_ptr = file_ptr;
|
|
}
|
|
|
|
static struct file *io_file_get(struct io_submit_state *state,
|
|
struct io_kiocb *req, int fd, bool fixed)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct file *file;
|
|
|
|
if (fixed) {
|
|
unsigned long file_ptr;
|
|
|
|
if (unlikely((unsigned int)fd >= ctx->nr_user_files))
|
|
return NULL;
|
|
fd = array_index_nospec(fd, ctx->nr_user_files);
|
|
file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
|
|
file = (struct file *) (file_ptr & FFS_MASK);
|
|
file_ptr &= ~FFS_MASK;
|
|
/* mask in overlapping REQ_F and FFS bits */
|
|
req->flags |= (file_ptr << REQ_F_ASYNC_READ_BIT);
|
|
io_req_set_rsrc_node(req);
|
|
} else {
|
|
trace_io_uring_file_get(ctx, fd);
|
|
file = __io_file_get(state, fd);
|
|
|
|
/* we don't allow fixed io_uring files */
|
|
if (file && unlikely(file->f_op == &io_uring_fops))
|
|
io_req_track_inflight(req);
|
|
}
|
|
|
|
return file;
|
|
}
|
|
|
|
static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
|
|
{
|
|
struct io_timeout_data *data = container_of(timer,
|
|
struct io_timeout_data, timer);
|
|
struct io_kiocb *prev, *req = data->req;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
prev = req->timeout.head;
|
|
req->timeout.head = NULL;
|
|
|
|
/*
|
|
* We don't expect the list to be empty, that will only happen if we
|
|
* race with the completion of the linked work.
|
|
*/
|
|
if (prev) {
|
|
io_remove_next_linked(prev);
|
|
if (!req_ref_inc_not_zero(prev))
|
|
prev = NULL;
|
|
}
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
|
|
if (prev) {
|
|
io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
|
|
io_put_req_deferred(prev, 1);
|
|
io_put_req_deferred(req, 1);
|
|
} else {
|
|
io_req_complete_post(req, -ETIME, 0);
|
|
}
|
|
return HRTIMER_NORESTART;
|
|
}
|
|
|
|
static void io_queue_linked_timeout(struct io_kiocb *req)
|
|
{
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
/*
|
|
* If the back reference is NULL, then our linked request finished
|
|
* before we got a chance to setup the timer
|
|
*/
|
|
if (req->timeout.head) {
|
|
struct io_timeout_data *data = req->async_data;
|
|
|
|
data->timer.function = io_link_timeout_fn;
|
|
hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
|
|
data->mode);
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
/* drop submission reference */
|
|
io_put_req(req);
|
|
}
|
|
|
|
static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *nxt = req->link;
|
|
|
|
if (!nxt || (req->flags & REQ_F_LINK_TIMEOUT) ||
|
|
nxt->opcode != IORING_OP_LINK_TIMEOUT)
|
|
return NULL;
|
|
|
|
nxt->timeout.head = req;
|
|
nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
|
|
req->flags |= REQ_F_LINK_TIMEOUT;
|
|
return nxt;
|
|
}
|
|
|
|
static void __io_queue_sqe(struct io_kiocb *req)
|
|
{
|
|
struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);
|
|
int ret;
|
|
|
|
issue_sqe:
|
|
ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
|
|
|
|
/*
|
|
* We async punt it if the file wasn't marked NOWAIT, or if the file
|
|
* doesn't support non-blocking read/write attempts
|
|
*/
|
|
if (likely(!ret)) {
|
|
/* drop submission reference */
|
|
if (req->flags & REQ_F_COMPLETE_INLINE) {
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
struct io_comp_state *cs = &ctx->submit_state.comp;
|
|
|
|
cs->reqs[cs->nr++] = req;
|
|
if (cs->nr == ARRAY_SIZE(cs->reqs))
|
|
io_submit_flush_completions(ctx);
|
|
} else {
|
|
io_put_req(req);
|
|
}
|
|
} else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
|
|
switch (io_arm_poll_handler(req)) {
|
|
case IO_APOLL_READY:
|
|
goto issue_sqe;
|
|
case IO_APOLL_ABORTED:
|
|
/*
|
|
* Queued up for async execution, worker will release
|
|
* submit reference when the iocb is actually submitted.
|
|
*/
|
|
io_queue_async_work(req);
|
|
break;
|
|
}
|
|
} else {
|
|
io_req_complete_failed(req, ret);
|
|
}
|
|
if (linked_timeout)
|
|
io_queue_linked_timeout(linked_timeout);
|
|
}
|
|
|
|
static inline void io_queue_sqe(struct io_kiocb *req)
|
|
{
|
|
if (unlikely(req->ctx->drain_active) && io_drain_req(req))
|
|
return;
|
|
|
|
if (likely(!(req->flags & REQ_F_FORCE_ASYNC))) {
|
|
__io_queue_sqe(req);
|
|
} else {
|
|
int ret = io_req_prep_async(req);
|
|
|
|
if (unlikely(ret))
|
|
io_req_complete_failed(req, ret);
|
|
else
|
|
io_queue_async_work(req);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check SQE restrictions (opcode and flags).
|
|
*
|
|
* Returns 'true' if SQE is allowed, 'false' otherwise.
|
|
*/
|
|
static inline bool io_check_restriction(struct io_ring_ctx *ctx,
|
|
struct io_kiocb *req,
|
|
unsigned int sqe_flags)
|
|
{
|
|
if (likely(!ctx->restricted))
|
|
return true;
|
|
|
|
if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
|
|
return false;
|
|
|
|
if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
|
|
ctx->restrictions.sqe_flags_required)
|
|
return false;
|
|
|
|
if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
|
|
ctx->restrictions.sqe_flags_required))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_submit_state *state;
|
|
unsigned int sqe_flags;
|
|
int personality, ret = 0;
|
|
|
|
req->opcode = READ_ONCE(sqe->opcode);
|
|
/* same numerical values with corresponding REQ_F_*, safe to copy */
|
|
req->flags = sqe_flags = READ_ONCE(sqe->flags);
|
|
req->user_data = READ_ONCE(sqe->user_data);
|
|
req->file = NULL;
|
|
req->fixed_rsrc_refs = NULL;
|
|
/* one is dropped after submission, the other at completion */
|
|
atomic_set(&req->refs, 2);
|
|
req->task = current;
|
|
|
|
/* enforce forwards compatibility on users */
|
|
if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
|
|
return -EINVAL;
|
|
if (unlikely(req->opcode >= IORING_OP_LAST))
|
|
return -EINVAL;
|
|
if (!io_check_restriction(ctx, req, sqe_flags))
|
|
return -EACCES;
|
|
|
|
if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
|
|
!io_op_defs[req->opcode].buffer_select)
|
|
return -EOPNOTSUPP;
|
|
if (unlikely(sqe_flags & IOSQE_IO_DRAIN))
|
|
ctx->drain_active = true;
|
|
|
|
personality = READ_ONCE(sqe->personality);
|
|
if (personality) {
|
|
req->creds = xa_load(&ctx->personalities, personality);
|
|
if (!req->creds)
|
|
return -EINVAL;
|
|
get_cred(req->creds);
|
|
req->flags |= REQ_F_CREDS;
|
|
}
|
|
state = &ctx->submit_state;
|
|
|
|
/*
|
|
* Plug now if we have more than 1 IO left after this, and the target
|
|
* is potentially a read/write to block based storage.
|
|
*/
|
|
if (!state->plug_started && state->ios_left > 1 &&
|
|
io_op_defs[req->opcode].plug) {
|
|
blk_start_plug(&state->plug);
|
|
state->plug_started = true;
|
|
}
|
|
|
|
if (io_op_defs[req->opcode].needs_file) {
|
|
bool fixed = req->flags & REQ_F_FIXED_FILE;
|
|
|
|
req->file = io_file_get(state, req, READ_ONCE(sqe->fd), fixed);
|
|
if (unlikely(!req->file))
|
|
ret = -EBADF;
|
|
}
|
|
|
|
state->ios_left--;
|
|
return ret;
|
|
}
|
|
|
|
static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
|
|
const struct io_uring_sqe *sqe)
|
|
{
|
|
struct io_submit_link *link = &ctx->submit_state.link;
|
|
int ret;
|
|
|
|
ret = io_init_req(ctx, req, sqe);
|
|
if (unlikely(ret)) {
|
|
fail_req:
|
|
if (link->head) {
|
|
/* fail even hard links since we don't submit */
|
|
req_set_fail(link->head);
|
|
io_req_complete_failed(link->head, -ECANCELED);
|
|
link->head = NULL;
|
|
}
|
|
io_req_complete_failed(req, ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = io_req_prep(req, sqe);
|
|
if (unlikely(ret))
|
|
goto fail_req;
|
|
|
|
/* don't need @sqe from now on */
|
|
trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
|
|
req->flags, true,
|
|
ctx->flags & IORING_SETUP_SQPOLL);
|
|
|
|
/*
|
|
* If we already have a head request, queue this one for async
|
|
* submittal once the head completes. If we don't have a head but
|
|
* IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
|
|
* submitted sync once the chain is complete. If none of those
|
|
* conditions are true (normal request), then just queue it.
|
|
*/
|
|
if (link->head) {
|
|
struct io_kiocb *head = link->head;
|
|
|
|
ret = io_req_prep_async(req);
|
|
if (unlikely(ret))
|
|
goto fail_req;
|
|
trace_io_uring_link(ctx, req, head);
|
|
link->last->link = req;
|
|
link->last = req;
|
|
|
|
/* last request of a link, enqueue the link */
|
|
if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
|
|
link->head = NULL;
|
|
io_queue_sqe(head);
|
|
}
|
|
} else {
|
|
if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
|
|
link->head = req;
|
|
link->last = req;
|
|
} else {
|
|
io_queue_sqe(req);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Batched submission is done, ensure local IO is flushed out.
|
|
*/
|
|
static void io_submit_state_end(struct io_submit_state *state,
|
|
struct io_ring_ctx *ctx)
|
|
{
|
|
if (state->link.head)
|
|
io_queue_sqe(state->link.head);
|
|
if (state->comp.nr)
|
|
io_submit_flush_completions(ctx);
|
|
if (state->plug_started)
|
|
blk_finish_plug(&state->plug);
|
|
io_state_file_put(state);
|
|
}
|
|
|
|
/*
|
|
* Start submission side cache.
|
|
*/
|
|
static void io_submit_state_start(struct io_submit_state *state,
|
|
unsigned int max_ios)
|
|
{
|
|
state->plug_started = false;
|
|
state->ios_left = max_ios;
|
|
/* set only head, no need to init link_last in advance */
|
|
state->link.head = NULL;
|
|
}
|
|
|
|
static void io_commit_sqring(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rings *rings = ctx->rings;
|
|
|
|
/*
|
|
* Ensure any loads from the SQEs are done at this point,
|
|
* since once we write the new head, the application could
|
|
* write new data to them.
|
|
*/
|
|
smp_store_release(&rings->sq.head, ctx->cached_sq_head);
|
|
}
|
|
|
|
/*
|
|
* Fetch an sqe, if one is available. Note this returns a pointer to memory
|
|
* that is mapped by userspace. This means that care needs to be taken to
|
|
* ensure that reads are stable, as we cannot rely on userspace always
|
|
* being a good citizen. If members of the sqe are validated and then later
|
|
* used, it's important that those reads are done through READ_ONCE() to
|
|
* prevent a re-load down the line.
|
|
*/
|
|
static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
|
|
{
|
|
unsigned head, mask = ctx->sq_entries - 1;
|
|
unsigned sq_idx = ctx->cached_sq_head++ & mask;
|
|
|
|
/*
|
|
* The cached sq head (or cq tail) serves two purposes:
|
|
*
|
|
* 1) allows us to batch the cost of updating the user visible
|
|
* head updates.
|
|
* 2) allows the kernel side to track the head on its own, even
|
|
* though the application is the one updating it.
|
|
*/
|
|
head = READ_ONCE(ctx->sq_array[sq_idx]);
|
|
if (likely(head < ctx->sq_entries))
|
|
return &ctx->sq_sqes[head];
|
|
|
|
/* drop invalid entries */
|
|
ctx->cq_extra--;
|
|
WRITE_ONCE(ctx->rings->sq_dropped,
|
|
READ_ONCE(ctx->rings->sq_dropped) + 1);
|
|
return NULL;
|
|
}
|
|
|
|
static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
|
|
{
|
|
struct io_uring_task *tctx;
|
|
int submitted = 0;
|
|
|
|
/* make sure SQ entry isn't read before tail */
|
|
nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
|
|
if (!percpu_ref_tryget_many(&ctx->refs, nr))
|
|
return -EAGAIN;
|
|
|
|
tctx = current->io_uring;
|
|
tctx->cached_refs -= nr;
|
|
if (unlikely(tctx->cached_refs < 0)) {
|
|
unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
|
|
|
|
percpu_counter_add(&tctx->inflight, refill);
|
|
refcount_add(refill, ¤t->usage);
|
|
tctx->cached_refs += refill;
|
|
}
|
|
io_submit_state_start(&ctx->submit_state, nr);
|
|
|
|
while (submitted < nr) {
|
|
const struct io_uring_sqe *sqe;
|
|
struct io_kiocb *req;
|
|
|
|
req = io_alloc_req(ctx);
|
|
if (unlikely(!req)) {
|
|
if (!submitted)
|
|
submitted = -EAGAIN;
|
|
break;
|
|
}
|
|
sqe = io_get_sqe(ctx);
|
|
if (unlikely(!sqe)) {
|
|
kmem_cache_free(req_cachep, req);
|
|
break;
|
|
}
|
|
/* will complete beyond this point, count as submitted */
|
|
submitted++;
|
|
if (io_submit_sqe(ctx, req, sqe))
|
|
break;
|
|
}
|
|
|
|
if (unlikely(submitted != nr)) {
|
|
int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
|
|
int unused = nr - ref_used;
|
|
|
|
current->io_uring->cached_refs += unused;
|
|
percpu_ref_put_many(&ctx->refs, unused);
|
|
}
|
|
|
|
io_submit_state_end(&ctx->submit_state, ctx);
|
|
/* Commit SQ ring head once we've consumed and submitted all SQEs */
|
|
io_commit_sqring(ctx);
|
|
|
|
return submitted;
|
|
}
|
|
|
|
static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
|
|
{
|
|
return READ_ONCE(sqd->state);
|
|
}
|
|
|
|
static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
|
|
{
|
|
/* Tell userspace we may need a wakeup call */
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
}
|
|
|
|
static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
|
|
{
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
}
|
|
|
|
static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
|
|
{
|
|
unsigned int to_submit;
|
|
int ret = 0;
|
|
|
|
to_submit = io_sqring_entries(ctx);
|
|
/* if we're handling multiple rings, cap submit size for fairness */
|
|
if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
|
|
to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
|
|
|
|
if (!list_empty(&ctx->iopoll_list) || to_submit) {
|
|
unsigned nr_events = 0;
|
|
const struct cred *creds = NULL;
|
|
|
|
if (ctx->sq_creds != current_cred())
|
|
creds = override_creds(ctx->sq_creds);
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
if (!list_empty(&ctx->iopoll_list))
|
|
io_do_iopoll(ctx, &nr_events, 0);
|
|
|
|
/*
|
|
* Don't submit if refs are dying, good for io_uring_register(),
|
|
* but also it is relied upon by io_ring_exit_work()
|
|
*/
|
|
if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
|
|
!(ctx->flags & IORING_SETUP_R_DISABLED))
|
|
ret = io_submit_sqes(ctx, to_submit);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
|
|
if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
|
|
wake_up(&ctx->sqo_sq_wait);
|
|
if (creds)
|
|
revert_creds(creds);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
unsigned sq_thread_idle = 0;
|
|
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
|
|
sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
|
|
sqd->sq_thread_idle = sq_thread_idle;
|
|
}
|
|
|
|
static bool io_sqd_handle_event(struct io_sq_data *sqd)
|
|
{
|
|
bool did_sig = false;
|
|
struct ksignal ksig;
|
|
|
|
if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
|
|
signal_pending(current)) {
|
|
mutex_unlock(&sqd->lock);
|
|
if (signal_pending(current))
|
|
did_sig = get_signal(&ksig);
|
|
cond_resched();
|
|
mutex_lock(&sqd->lock);
|
|
}
|
|
return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
|
|
}
|
|
|
|
static int io_sq_thread(void *data)
|
|
{
|
|
struct io_sq_data *sqd = data;
|
|
struct io_ring_ctx *ctx;
|
|
unsigned long timeout = 0;
|
|
char buf[TASK_COMM_LEN];
|
|
DEFINE_WAIT(wait);
|
|
|
|
snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
|
|
set_task_comm(current, buf);
|
|
|
|
if (sqd->sq_cpu != -1)
|
|
set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
|
|
else
|
|
set_cpus_allowed_ptr(current, cpu_online_mask);
|
|
current->flags |= PF_NO_SETAFFINITY;
|
|
|
|
mutex_lock(&sqd->lock);
|
|
while (1) {
|
|
bool cap_entries, sqt_spin = false;
|
|
|
|
if (io_sqd_events_pending(sqd) || signal_pending(current)) {
|
|
if (io_sqd_handle_event(sqd))
|
|
break;
|
|
timeout = jiffies + sqd->sq_thread_idle;
|
|
}
|
|
|
|
cap_entries = !list_is_singular(&sqd->ctx_list);
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
|
|
int ret = __io_sq_thread(ctx, cap_entries);
|
|
|
|
if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
|
|
sqt_spin = true;
|
|
}
|
|
if (io_run_task_work())
|
|
sqt_spin = true;
|
|
|
|
if (sqt_spin || !time_after(jiffies, timeout)) {
|
|
cond_resched();
|
|
if (sqt_spin)
|
|
timeout = jiffies + sqd->sq_thread_idle;
|
|
continue;
|
|
}
|
|
|
|
prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
|
|
if (!io_sqd_events_pending(sqd) && !current->task_works) {
|
|
bool needs_sched = true;
|
|
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
|
|
io_ring_set_wakeup_flag(ctx);
|
|
|
|
if ((ctx->flags & IORING_SETUP_IOPOLL) &&
|
|
!list_empty_careful(&ctx->iopoll_list)) {
|
|
needs_sched = false;
|
|
break;
|
|
}
|
|
if (io_sqring_entries(ctx)) {
|
|
needs_sched = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (needs_sched) {
|
|
mutex_unlock(&sqd->lock);
|
|
schedule();
|
|
mutex_lock(&sqd->lock);
|
|
}
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
|
|
io_ring_clear_wakeup_flag(ctx);
|
|
}
|
|
|
|
finish_wait(&sqd->wait, &wait);
|
|
timeout = jiffies + sqd->sq_thread_idle;
|
|
}
|
|
|
|
io_uring_cancel_generic(true, sqd);
|
|
sqd->thread = NULL;
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
|
|
io_ring_set_wakeup_flag(ctx);
|
|
io_run_task_work();
|
|
mutex_unlock(&sqd->lock);
|
|
|
|
complete(&sqd->exited);
|
|
do_exit(0);
|
|
}
|
|
|
|
struct io_wait_queue {
|
|
struct wait_queue_entry wq;
|
|
struct io_ring_ctx *ctx;
|
|
unsigned to_wait;
|
|
unsigned nr_timeouts;
|
|
};
|
|
|
|
static inline bool io_should_wake(struct io_wait_queue *iowq)
|
|
{
|
|
struct io_ring_ctx *ctx = iowq->ctx;
|
|
|
|
/*
|
|
* Wake up if we have enough events, or if a timeout occurred since we
|
|
* started waiting. For timeouts, we always want to return to userspace,
|
|
* regardless of event count.
|
|
*/
|
|
return io_cqring_events(ctx) >= iowq->to_wait ||
|
|
atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
|
|
}
|
|
|
|
static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
|
|
int wake_flags, void *key)
|
|
{
|
|
struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
|
|
wq);
|
|
|
|
/*
|
|
* Cannot safely flush overflowed CQEs from here, ensure we wake up
|
|
* the task, and the next invocation will do it.
|
|
*/
|
|
if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
|
|
return autoremove_wake_function(curr, mode, wake_flags, key);
|
|
return -1;
|
|
}
|
|
|
|
static int io_run_task_work_sig(void)
|
|
{
|
|
if (io_run_task_work())
|
|
return 1;
|
|
if (!signal_pending(current))
|
|
return 0;
|
|
if (test_thread_flag(TIF_NOTIFY_SIGNAL))
|
|
return -ERESTARTSYS;
|
|
return -EINTR;
|
|
}
|
|
|
|
/* when returns >0, the caller should retry */
|
|
static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
|
|
struct io_wait_queue *iowq,
|
|
signed long *timeout)
|
|
{
|
|
int ret;
|
|
|
|
/* make sure we run task_work before checking for signals */
|
|
ret = io_run_task_work_sig();
|
|
if (ret || io_should_wake(iowq))
|
|
return ret;
|
|
/* let the caller flush overflows, retry */
|
|
if (test_bit(0, &ctx->check_cq_overflow))
|
|
return 1;
|
|
|
|
*timeout = schedule_timeout(*timeout);
|
|
return !*timeout ? -ETIME : 1;
|
|
}
|
|
|
|
/*
|
|
* Wait until events become available, if we don't already have some. The
|
|
* application must reap them itself, as they reside on the shared cq ring.
|
|
*/
|
|
static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
|
|
const sigset_t __user *sig, size_t sigsz,
|
|
struct __kernel_timespec __user *uts)
|
|
{
|
|
struct io_wait_queue iowq = {
|
|
.wq = {
|
|
.private = current,
|
|
.func = io_wake_function,
|
|
.entry = LIST_HEAD_INIT(iowq.wq.entry),
|
|
},
|
|
.ctx = ctx,
|
|
.to_wait = min_events,
|
|
};
|
|
struct io_rings *rings = ctx->rings;
|
|
signed long timeout = MAX_SCHEDULE_TIMEOUT;
|
|
int ret;
|
|
|
|
do {
|
|
io_cqring_overflow_flush(ctx, false);
|
|
if (io_cqring_events(ctx) >= min_events)
|
|
return 0;
|
|
if (!io_run_task_work())
|
|
break;
|
|
} while (1);
|
|
|
|
if (sig) {
|
|
#ifdef CONFIG_COMPAT
|
|
if (in_compat_syscall())
|
|
ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
|
|
sigsz);
|
|
else
|
|
#endif
|
|
ret = set_user_sigmask(sig, sigsz);
|
|
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
if (uts) {
|
|
struct timespec64 ts;
|
|
|
|
if (get_timespec64(&ts, uts))
|
|
return -EFAULT;
|
|
timeout = timespec64_to_jiffies(&ts);
|
|
}
|
|
|
|
iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
|
|
trace_io_uring_cqring_wait(ctx, min_events);
|
|
do {
|
|
/* if we can't even flush overflow, don't wait for more */
|
|
if (!io_cqring_overflow_flush(ctx, false)) {
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
|
|
TASK_INTERRUPTIBLE);
|
|
ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
|
|
finish_wait(&ctx->cq_wait, &iowq.wq);
|
|
cond_resched();
|
|
} while (ret > 0);
|
|
|
|
restore_saved_sigmask_unless(ret == -EINTR);
|
|
|
|
return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
|
|
}
|
|
|
|
static void io_free_page_table(void **table, size_t size)
|
|
{
|
|
unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
|
|
|
|
for (i = 0; i < nr_tables; i++)
|
|
kfree(table[i]);
|
|
kfree(table);
|
|
}
|
|
|
|
static void **io_alloc_page_table(size_t size)
|
|
{
|
|
unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
|
|
size_t init_size = size;
|
|
void **table;
|
|
|
|
table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL);
|
|
if (!table)
|
|
return NULL;
|
|
|
|
for (i = 0; i < nr_tables; i++) {
|
|
unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
|
|
|
|
table[i] = kzalloc(this_size, GFP_KERNEL);
|
|
if (!table[i]) {
|
|
io_free_page_table(table, init_size);
|
|
return NULL;
|
|
}
|
|
size -= this_size;
|
|
}
|
|
return table;
|
|
}
|
|
|
|
static inline void io_rsrc_ref_lock(struct io_ring_ctx *ctx)
|
|
{
|
|
spin_lock_bh(&ctx->rsrc_ref_lock);
|
|
}
|
|
|
|
static inline void io_rsrc_ref_unlock(struct io_ring_ctx *ctx)
|
|
{
|
|
spin_unlock_bh(&ctx->rsrc_ref_lock);
|
|
}
|
|
|
|
static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
|
|
{
|
|
percpu_ref_exit(&ref_node->refs);
|
|
kfree(ref_node);
|
|
}
|
|
|
|
static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
|
|
struct io_rsrc_data *data_to_kill)
|
|
{
|
|
WARN_ON_ONCE(!ctx->rsrc_backup_node);
|
|
WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
|
|
|
|
if (data_to_kill) {
|
|
struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
|
|
|
|
rsrc_node->rsrc_data = data_to_kill;
|
|
io_rsrc_ref_lock(ctx);
|
|
list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
|
|
io_rsrc_ref_unlock(ctx);
|
|
|
|
atomic_inc(&data_to_kill->refs);
|
|
percpu_ref_kill(&rsrc_node->refs);
|
|
ctx->rsrc_node = NULL;
|
|
}
|
|
|
|
if (!ctx->rsrc_node) {
|
|
ctx->rsrc_node = ctx->rsrc_backup_node;
|
|
ctx->rsrc_backup_node = NULL;
|
|
}
|
|
}
|
|
|
|
static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
|
|
{
|
|
if (ctx->rsrc_backup_node)
|
|
return 0;
|
|
ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
|
|
return ctx->rsrc_backup_node ? 0 : -ENOMEM;
|
|
}
|
|
|
|
static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx)
|
|
{
|
|
int ret;
|
|
|
|
/* As we may drop ->uring_lock, other task may have started quiesce */
|
|
if (data->quiesce)
|
|
return -ENXIO;
|
|
|
|
data->quiesce = true;
|
|
do {
|
|
ret = io_rsrc_node_switch_start(ctx);
|
|
if (ret)
|
|
break;
|
|
io_rsrc_node_switch(ctx, data);
|
|
|
|
/* kill initial ref, already quiesced if zero */
|
|
if (atomic_dec_and_test(&data->refs))
|
|
break;
|
|
flush_delayed_work(&ctx->rsrc_put_work);
|
|
ret = wait_for_completion_interruptible(&data->done);
|
|
if (!ret)
|
|
break;
|
|
|
|
atomic_inc(&data->refs);
|
|
/* wait for all works potentially completing data->done */
|
|
flush_delayed_work(&ctx->rsrc_put_work);
|
|
reinit_completion(&data->done);
|
|
|
|
mutex_unlock(&ctx->uring_lock);
|
|
ret = io_run_task_work_sig();
|
|
mutex_lock(&ctx->uring_lock);
|
|
} while (ret >= 0);
|
|
data->quiesce = false;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
|
|
{
|
|
unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
|
|
unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
|
|
|
|
return &data->tags[table_idx][off];
|
|
}
|
|
|
|
static void io_rsrc_data_free(struct io_rsrc_data *data)
|
|
{
|
|
size_t size = data->nr * sizeof(data->tags[0][0]);
|
|
|
|
if (data->tags)
|
|
io_free_page_table((void **)data->tags, size);
|
|
kfree(data);
|
|
}
|
|
|
|
static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
|
|
u64 __user *utags, unsigned nr,
|
|
struct io_rsrc_data **pdata)
|
|
{
|
|
struct io_rsrc_data *data;
|
|
int ret = -ENOMEM;
|
|
unsigned i;
|
|
|
|
data = kzalloc(sizeof(*data), GFP_KERNEL);
|
|
if (!data)
|
|
return -ENOMEM;
|
|
data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
|
|
if (!data->tags) {
|
|
kfree(data);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
data->nr = nr;
|
|
data->ctx = ctx;
|
|
data->do_put = do_put;
|
|
if (utags) {
|
|
ret = -EFAULT;
|
|
for (i = 0; i < nr; i++) {
|
|
u64 *tag_slot = io_get_tag_slot(data, i);
|
|
|
|
if (copy_from_user(tag_slot, &utags[i],
|
|
sizeof(*tag_slot)))
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
atomic_set(&data->refs, 1);
|
|
init_completion(&data->done);
|
|
*pdata = data;
|
|
return 0;
|
|
fail:
|
|
io_rsrc_data_free(data);
|
|
return ret;
|
|
}
|
|
|
|
static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
|
|
{
|
|
size_t size = nr_files * sizeof(struct io_fixed_file);
|
|
|
|
table->files = (struct io_fixed_file **)io_alloc_page_table(size);
|
|
return !!table->files;
|
|
}
|
|
|
|
static void io_free_file_tables(struct io_file_table *table, unsigned nr_files)
|
|
{
|
|
size_t size = nr_files * sizeof(struct io_fixed_file);
|
|
|
|
io_free_page_table((void **)table->files, size);
|
|
table->files = NULL;
|
|
}
|
|
|
|
static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
|
|
{
|
|
#if defined(CONFIG_UNIX)
|
|
if (ctx->ring_sock) {
|
|
struct sock *sock = ctx->ring_sock->sk;
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
|
|
kfree_skb(skb);
|
|
}
|
|
#else
|
|
int i;
|
|
|
|
for (i = 0; i < ctx->nr_user_files; i++) {
|
|
struct file *file;
|
|
|
|
file = io_file_from_index(ctx, i);
|
|
if (file)
|
|
fput(file);
|
|
}
|
|
#endif
|
|
io_free_file_tables(&ctx->file_table, ctx->nr_user_files);
|
|
io_rsrc_data_free(ctx->file_data);
|
|
ctx->file_data = NULL;
|
|
ctx->nr_user_files = 0;
|
|
}
|
|
|
|
static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
|
|
{
|
|
int ret;
|
|
|
|
if (!ctx->file_data)
|
|
return -ENXIO;
|
|
ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
|
|
if (!ret)
|
|
__io_sqe_files_unregister(ctx);
|
|
return ret;
|
|
}
|
|
|
|
static void io_sq_thread_unpark(struct io_sq_data *sqd)
|
|
__releases(&sqd->lock)
|
|
{
|
|
WARN_ON_ONCE(sqd->thread == current);
|
|
|
|
/*
|
|
* Do the dance but not conditional clear_bit() because it'd race with
|
|
* other threads incrementing park_pending and setting the bit.
|
|
*/
|
|
clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
|
|
if (atomic_dec_return(&sqd->park_pending))
|
|
set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
|
|
mutex_unlock(&sqd->lock);
|
|
}
|
|
|
|
static void io_sq_thread_park(struct io_sq_data *sqd)
|
|
__acquires(&sqd->lock)
|
|
{
|
|
WARN_ON_ONCE(sqd->thread == current);
|
|
|
|
atomic_inc(&sqd->park_pending);
|
|
set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
|
|
mutex_lock(&sqd->lock);
|
|
if (sqd->thread)
|
|
wake_up_process(sqd->thread);
|
|
}
|
|
|
|
static void io_sq_thread_stop(struct io_sq_data *sqd)
|
|
{
|
|
WARN_ON_ONCE(sqd->thread == current);
|
|
WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
|
|
|
|
set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
|
|
mutex_lock(&sqd->lock);
|
|
if (sqd->thread)
|
|
wake_up_process(sqd->thread);
|
|
mutex_unlock(&sqd->lock);
|
|
wait_for_completion(&sqd->exited);
|
|
}
|
|
|
|
static void io_put_sq_data(struct io_sq_data *sqd)
|
|
{
|
|
if (refcount_dec_and_test(&sqd->refs)) {
|
|
WARN_ON_ONCE(atomic_read(&sqd->park_pending));
|
|
|
|
io_sq_thread_stop(sqd);
|
|
kfree(sqd);
|
|
}
|
|
}
|
|
|
|
static void io_sq_thread_finish(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_sq_data *sqd = ctx->sq_data;
|
|
|
|
if (sqd) {
|
|
io_sq_thread_park(sqd);
|
|
list_del_init(&ctx->sqd_list);
|
|
io_sqd_update_thread_idle(sqd);
|
|
io_sq_thread_unpark(sqd);
|
|
|
|
io_put_sq_data(sqd);
|
|
ctx->sq_data = NULL;
|
|
}
|
|
}
|
|
|
|
static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
|
|
{
|
|
struct io_ring_ctx *ctx_attach;
|
|
struct io_sq_data *sqd;
|
|
struct fd f;
|
|
|
|
f = fdget(p->wq_fd);
|
|
if (!f.file)
|
|
return ERR_PTR(-ENXIO);
|
|
if (f.file->f_op != &io_uring_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
ctx_attach = f.file->private_data;
|
|
sqd = ctx_attach->sq_data;
|
|
if (!sqd) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
if (sqd->task_tgid != current->tgid) {
|
|
fdput(f);
|
|
return ERR_PTR(-EPERM);
|
|
}
|
|
|
|
refcount_inc(&sqd->refs);
|
|
fdput(f);
|
|
return sqd;
|
|
}
|
|
|
|
static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
|
|
bool *attached)
|
|
{
|
|
struct io_sq_data *sqd;
|
|
|
|
*attached = false;
|
|
if (p->flags & IORING_SETUP_ATTACH_WQ) {
|
|
sqd = io_attach_sq_data(p);
|
|
if (!IS_ERR(sqd)) {
|
|
*attached = true;
|
|
return sqd;
|
|
}
|
|
/* fall through for EPERM case, setup new sqd/task */
|
|
if (PTR_ERR(sqd) != -EPERM)
|
|
return sqd;
|
|
}
|
|
|
|
sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
|
|
if (!sqd)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
atomic_set(&sqd->park_pending, 0);
|
|
refcount_set(&sqd->refs, 1);
|
|
INIT_LIST_HEAD(&sqd->ctx_list);
|
|
mutex_init(&sqd->lock);
|
|
init_waitqueue_head(&sqd->wait);
|
|
init_completion(&sqd->exited);
|
|
return sqd;
|
|
}
|
|
|
|
#if defined(CONFIG_UNIX)
|
|
/*
|
|
* Ensure the UNIX gc is aware of our file set, so we are certain that
|
|
* the io_uring can be safely unregistered on process exit, even if we have
|
|
* loops in the file referencing.
|
|
*/
|
|
static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
|
|
{
|
|
struct sock *sk = ctx->ring_sock->sk;
|
|
struct scm_fp_list *fpl;
|
|
struct sk_buff *skb;
|
|
int i, nr_files;
|
|
|
|
fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
|
|
if (!fpl)
|
|
return -ENOMEM;
|
|
|
|
skb = alloc_skb(0, GFP_KERNEL);
|
|
if (!skb) {
|
|
kfree(fpl);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
skb->sk = sk;
|
|
|
|
nr_files = 0;
|
|
fpl->user = get_uid(current_user());
|
|
for (i = 0; i < nr; i++) {
|
|
struct file *file = io_file_from_index(ctx, i + offset);
|
|
|
|
if (!file)
|
|
continue;
|
|
fpl->fp[nr_files] = get_file(file);
|
|
unix_inflight(fpl->user, fpl->fp[nr_files]);
|
|
nr_files++;
|
|
}
|
|
|
|
if (nr_files) {
|
|
fpl->max = SCM_MAX_FD;
|
|
fpl->count = nr_files;
|
|
UNIXCB(skb).fp = fpl;
|
|
skb->destructor = unix_destruct_scm;
|
|
refcount_add(skb->truesize, &sk->sk_wmem_alloc);
|
|
skb_queue_head(&sk->sk_receive_queue, skb);
|
|
|
|
for (i = 0; i < nr_files; i++)
|
|
fput(fpl->fp[i]);
|
|
} else {
|
|
kfree_skb(skb);
|
|
kfree(fpl);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If UNIX sockets are enabled, fd passing can cause a reference cycle which
|
|
* causes regular reference counting to break down. We rely on the UNIX
|
|
* garbage collection to take care of this problem for us.
|
|
*/
|
|
static int io_sqe_files_scm(struct io_ring_ctx *ctx)
|
|
{
|
|
unsigned left, total;
|
|
int ret = 0;
|
|
|
|
total = 0;
|
|
left = ctx->nr_user_files;
|
|
while (left) {
|
|
unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
|
|
|
|
ret = __io_sqe_files_scm(ctx, this_files, total);
|
|
if (ret)
|
|
break;
|
|
left -= this_files;
|
|
total += this_files;
|
|
}
|
|
|
|
if (!ret)
|
|
return 0;
|
|
|
|
while (total < ctx->nr_user_files) {
|
|
struct file *file = io_file_from_index(ctx, total);
|
|
|
|
if (file)
|
|
fput(file);
|
|
total++;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
#else
|
|
static int io_sqe_files_scm(struct io_ring_ctx *ctx)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
|
|
{
|
|
struct file *file = prsrc->file;
|
|
#if defined(CONFIG_UNIX)
|
|
struct sock *sock = ctx->ring_sock->sk;
|
|
struct sk_buff_head list, *head = &sock->sk_receive_queue;
|
|
struct sk_buff *skb;
|
|
int i;
|
|
|
|
__skb_queue_head_init(&list);
|
|
|
|
/*
|
|
* Find the skb that holds this file in its SCM_RIGHTS. When found,
|
|
* remove this entry and rearrange the file array.
|
|
*/
|
|
skb = skb_dequeue(head);
|
|
while (skb) {
|
|
struct scm_fp_list *fp;
|
|
|
|
fp = UNIXCB(skb).fp;
|
|
for (i = 0; i < fp->count; i++) {
|
|
int left;
|
|
|
|
if (fp->fp[i] != file)
|
|
continue;
|
|
|
|
unix_notinflight(fp->user, fp->fp[i]);
|
|
left = fp->count - 1 - i;
|
|
if (left) {
|
|
memmove(&fp->fp[i], &fp->fp[i + 1],
|
|
left * sizeof(struct file *));
|
|
}
|
|
fp->count--;
|
|
if (!fp->count) {
|
|
kfree_skb(skb);
|
|
skb = NULL;
|
|
} else {
|
|
__skb_queue_tail(&list, skb);
|
|
}
|
|
fput(file);
|
|
file = NULL;
|
|
break;
|
|
}
|
|
|
|
if (!file)
|
|
break;
|
|
|
|
__skb_queue_tail(&list, skb);
|
|
|
|
skb = skb_dequeue(head);
|
|
}
|
|
|
|
if (skb_peek(&list)) {
|
|
spin_lock_irq(&head->lock);
|
|
while ((skb = __skb_dequeue(&list)) != NULL)
|
|
__skb_queue_tail(head, skb);
|
|
spin_unlock_irq(&head->lock);
|
|
}
|
|
#else
|
|
fput(file);
|
|
#endif
|
|
}
|
|
|
|
static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
|
|
{
|
|
struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
|
|
struct io_ring_ctx *ctx = rsrc_data->ctx;
|
|
struct io_rsrc_put *prsrc, *tmp;
|
|
|
|
list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
|
|
list_del(&prsrc->list);
|
|
|
|
if (prsrc->tag) {
|
|
bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
|
|
|
|
io_ring_submit_lock(ctx, lock_ring);
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
io_cqring_fill_event(ctx, prsrc->tag, 0, 0);
|
|
ctx->cq_extra++;
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
io_cqring_ev_posted(ctx);
|
|
io_ring_submit_unlock(ctx, lock_ring);
|
|
}
|
|
|
|
rsrc_data->do_put(ctx, prsrc);
|
|
kfree(prsrc);
|
|
}
|
|
|
|
io_rsrc_node_destroy(ref_node);
|
|
if (atomic_dec_and_test(&rsrc_data->refs))
|
|
complete(&rsrc_data->done);
|
|
}
|
|
|
|
static void io_rsrc_put_work(struct work_struct *work)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
struct llist_node *node;
|
|
|
|
ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
|
|
node = llist_del_all(&ctx->rsrc_put_llist);
|
|
|
|
while (node) {
|
|
struct io_rsrc_node *ref_node;
|
|
struct llist_node *next = node->next;
|
|
|
|
ref_node = llist_entry(node, struct io_rsrc_node, llist);
|
|
__io_rsrc_put_work(ref_node);
|
|
node = next;
|
|
}
|
|
}
|
|
|
|
static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
|
|
{
|
|
struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
|
|
struct io_ring_ctx *ctx = node->rsrc_data->ctx;
|
|
bool first_add = false;
|
|
|
|
io_rsrc_ref_lock(ctx);
|
|
node->done = true;
|
|
|
|
while (!list_empty(&ctx->rsrc_ref_list)) {
|
|
node = list_first_entry(&ctx->rsrc_ref_list,
|
|
struct io_rsrc_node, node);
|
|
/* recycle ref nodes in order */
|
|
if (!node->done)
|
|
break;
|
|
list_del(&node->node);
|
|
first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
|
|
}
|
|
io_rsrc_ref_unlock(ctx);
|
|
|
|
if (first_add)
|
|
mod_delayed_work(system_wq, &ctx->rsrc_put_work, HZ);
|
|
}
|
|
|
|
static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_rsrc_node *ref_node;
|
|
|
|
ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
|
|
if (!ref_node)
|
|
return NULL;
|
|
|
|
if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
|
|
0, GFP_KERNEL)) {
|
|
kfree(ref_node);
|
|
return NULL;
|
|
}
|
|
INIT_LIST_HEAD(&ref_node->node);
|
|
INIT_LIST_HEAD(&ref_node->rsrc_list);
|
|
ref_node->done = false;
|
|
return ref_node;
|
|
}
|
|
|
|
static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned nr_args, u64 __user *tags)
|
|
{
|
|
__s32 __user *fds = (__s32 __user *) arg;
|
|
struct file *file;
|
|
int fd, ret;
|
|
unsigned i;
|
|
|
|
if (ctx->file_data)
|
|
return -EBUSY;
|
|
if (!nr_args)
|
|
return -EINVAL;
|
|
if (nr_args > IORING_MAX_FIXED_FILES)
|
|
return -EMFILE;
|
|
ret = io_rsrc_node_switch_start(ctx);
|
|
if (ret)
|
|
return ret;
|
|
ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
|
|
&ctx->file_data);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = -ENOMEM;
|
|
if (!io_alloc_file_tables(&ctx->file_table, nr_args))
|
|
goto out_free;
|
|
|
|
for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
|
|
if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
|
|
ret = -EFAULT;
|
|
goto out_fput;
|
|
}
|
|
/* allow sparse sets */
|
|
if (fd == -1) {
|
|
ret = -EINVAL;
|
|
if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
|
|
goto out_fput;
|
|
continue;
|
|
}
|
|
|
|
file = fget(fd);
|
|
ret = -EBADF;
|
|
if (unlikely(!file))
|
|
goto out_fput;
|
|
|
|
/*
|
|
* Don't allow io_uring instances to be registered. If UNIX
|
|
* isn't enabled, then this causes a reference cycle and this
|
|
* instance can never get freed. If UNIX is enabled we'll
|
|
* handle it just fine, but there's still no point in allowing
|
|
* a ring fd as it doesn't support regular read/write anyway.
|
|
*/
|
|
if (file->f_op == &io_uring_fops) {
|
|
fput(file);
|
|
goto out_fput;
|
|
}
|
|
io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
|
|
}
|
|
|
|
ret = io_sqe_files_scm(ctx);
|
|
if (ret) {
|
|
__io_sqe_files_unregister(ctx);
|
|
return ret;
|
|
}
|
|
|
|
io_rsrc_node_switch(ctx, NULL);
|
|
return ret;
|
|
out_fput:
|
|
for (i = 0; i < ctx->nr_user_files; i++) {
|
|
file = io_file_from_index(ctx, i);
|
|
if (file)
|
|
fput(file);
|
|
}
|
|
io_free_file_tables(&ctx->file_table, nr_args);
|
|
ctx->nr_user_files = 0;
|
|
out_free:
|
|
io_rsrc_data_free(ctx->file_data);
|
|
ctx->file_data = NULL;
|
|
return ret;
|
|
}
|
|
|
|
static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
|
|
int index)
|
|
{
|
|
#if defined(CONFIG_UNIX)
|
|
struct sock *sock = ctx->ring_sock->sk;
|
|
struct sk_buff_head *head = &sock->sk_receive_queue;
|
|
struct sk_buff *skb;
|
|
|
|
/*
|
|
* See if we can merge this file into an existing skb SCM_RIGHTS
|
|
* file set. If there's no room, fall back to allocating a new skb
|
|
* and filling it in.
|
|
*/
|
|
spin_lock_irq(&head->lock);
|
|
skb = skb_peek(head);
|
|
if (skb) {
|
|
struct scm_fp_list *fpl = UNIXCB(skb).fp;
|
|
|
|
if (fpl->count < SCM_MAX_FD) {
|
|
__skb_unlink(skb, head);
|
|
spin_unlock_irq(&head->lock);
|
|
fpl->fp[fpl->count] = get_file(file);
|
|
unix_inflight(fpl->user, fpl->fp[fpl->count]);
|
|
fpl->count++;
|
|
spin_lock_irq(&head->lock);
|
|
__skb_queue_head(head, skb);
|
|
} else {
|
|
skb = NULL;
|
|
}
|
|
}
|
|
spin_unlock_irq(&head->lock);
|
|
|
|
if (skb) {
|
|
fput(file);
|
|
return 0;
|
|
}
|
|
|
|
return __io_sqe_files_scm(ctx, 1, index);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
|
|
struct io_rsrc_node *node, void *rsrc)
|
|
{
|
|
struct io_rsrc_put *prsrc;
|
|
|
|
prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
|
|
if (!prsrc)
|
|
return -ENOMEM;
|
|
|
|
prsrc->tag = *io_get_tag_slot(data, idx);
|
|
prsrc->rsrc = rsrc;
|
|
list_add(&prsrc->list, &node->rsrc_list);
|
|
return 0;
|
|
}
|
|
|
|
static int __io_sqe_files_update(struct io_ring_ctx *ctx,
|
|
struct io_uring_rsrc_update2 *up,
|
|
unsigned nr_args)
|
|
{
|
|
u64 __user *tags = u64_to_user_ptr(up->tags);
|
|
__s32 __user *fds = u64_to_user_ptr(up->data);
|
|
struct io_rsrc_data *data = ctx->file_data;
|
|
struct io_fixed_file *file_slot;
|
|
struct file *file;
|
|
int fd, i, err = 0;
|
|
unsigned int done;
|
|
bool needs_switch = false;
|
|
|
|
if (!ctx->file_data)
|
|
return -ENXIO;
|
|
if (up->offset + nr_args > ctx->nr_user_files)
|
|
return -EINVAL;
|
|
|
|
for (done = 0; done < nr_args; done++) {
|
|
u64 tag = 0;
|
|
|
|
if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
|
|
copy_from_user(&fd, &fds[done], sizeof(fd))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
if (fd == IORING_REGISTER_FILES_SKIP)
|
|
continue;
|
|
|
|
i = array_index_nospec(up->offset + done, ctx->nr_user_files);
|
|
file_slot = io_fixed_file_slot(&ctx->file_table, i);
|
|
|
|
if (file_slot->file_ptr) {
|
|
file = (struct file *)(file_slot->file_ptr & FFS_MASK);
|
|
err = io_queue_rsrc_removal(data, up->offset + done,
|
|
ctx->rsrc_node, file);
|
|
if (err)
|
|
break;
|
|
file_slot->file_ptr = 0;
|
|
needs_switch = true;
|
|
}
|
|
if (fd != -1) {
|
|
file = fget(fd);
|
|
if (!file) {
|
|
err = -EBADF;
|
|
break;
|
|
}
|
|
/*
|
|
* Don't allow io_uring instances to be registered. If
|
|
* UNIX isn't enabled, then this causes a reference
|
|
* cycle and this instance can never get freed. If UNIX
|
|
* is enabled we'll handle it just fine, but there's
|
|
* still no point in allowing a ring fd as it doesn't
|
|
* support regular read/write anyway.
|
|
*/
|
|
if (file->f_op == &io_uring_fops) {
|
|
fput(file);
|
|
err = -EBADF;
|
|
break;
|
|
}
|
|
*io_get_tag_slot(data, up->offset + done) = tag;
|
|
io_fixed_file_set(file_slot, file);
|
|
err = io_sqe_file_register(ctx, file, i);
|
|
if (err) {
|
|
file_slot->file_ptr = 0;
|
|
fput(file);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (needs_switch)
|
|
io_rsrc_node_switch(ctx, data);
|
|
return done ? done : err;
|
|
}
|
|
|
|
static struct io_wq_work *io_free_work(struct io_wq_work *work)
|
|
{
|
|
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
|
|
|
|
req = io_put_req_find_next(req);
|
|
return req ? &req->work : NULL;
|
|
}
|
|
|
|
static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
|
|
struct task_struct *task)
|
|
{
|
|
struct io_wq_hash *hash;
|
|
struct io_wq_data data;
|
|
unsigned int concurrency;
|
|
|
|
hash = ctx->hash_map;
|
|
if (!hash) {
|
|
hash = kzalloc(sizeof(*hash), GFP_KERNEL);
|
|
if (!hash)
|
|
return ERR_PTR(-ENOMEM);
|
|
refcount_set(&hash->refs, 1);
|
|
init_waitqueue_head(&hash->wait);
|
|
ctx->hash_map = hash;
|
|
}
|
|
|
|
data.hash = hash;
|
|
data.task = task;
|
|
data.free_work = io_free_work;
|
|
data.do_work = io_wq_submit_work;
|
|
|
|
/* Do QD, or 4 * CPUS, whatever is smallest */
|
|
concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
|
|
|
|
return io_wq_create(concurrency, &data);
|
|
}
|
|
|
|
static int io_uring_alloc_task_context(struct task_struct *task,
|
|
struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_uring_task *tctx;
|
|
int ret;
|
|
|
|
tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
|
|
if (unlikely(!tctx))
|
|
return -ENOMEM;
|
|
|
|
ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
|
|
if (unlikely(ret)) {
|
|
kfree(tctx);
|
|
return ret;
|
|
}
|
|
|
|
tctx->io_wq = io_init_wq_offload(ctx, task);
|
|
if (IS_ERR(tctx->io_wq)) {
|
|
ret = PTR_ERR(tctx->io_wq);
|
|
percpu_counter_destroy(&tctx->inflight);
|
|
kfree(tctx);
|
|
return ret;
|
|
}
|
|
|
|
xa_init(&tctx->xa);
|
|
init_waitqueue_head(&tctx->wait);
|
|
atomic_set(&tctx->in_idle, 0);
|
|
atomic_set(&tctx->inflight_tracked, 0);
|
|
task->io_uring = tctx;
|
|
spin_lock_init(&tctx->task_lock);
|
|
INIT_WQ_LIST(&tctx->task_list);
|
|
init_task_work(&tctx->task_work, tctx_task_work);
|
|
return 0;
|
|
}
|
|
|
|
void __io_uring_free(struct task_struct *tsk)
|
|
{
|
|
struct io_uring_task *tctx = tsk->io_uring;
|
|
|
|
WARN_ON_ONCE(!xa_empty(&tctx->xa));
|
|
WARN_ON_ONCE(tctx->io_wq);
|
|
WARN_ON_ONCE(tctx->cached_refs);
|
|
|
|
percpu_counter_destroy(&tctx->inflight);
|
|
kfree(tctx);
|
|
tsk->io_uring = NULL;
|
|
}
|
|
|
|
static int io_sq_offload_create(struct io_ring_ctx *ctx,
|
|
struct io_uring_params *p)
|
|
{
|
|
int ret;
|
|
|
|
/* Retain compatibility with failing for an invalid attach attempt */
|
|
if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
|
|
IORING_SETUP_ATTACH_WQ) {
|
|
struct fd f;
|
|
|
|
f = fdget(p->wq_fd);
|
|
if (!f.file)
|
|
return -ENXIO;
|
|
fdput(f);
|
|
if (f.file->f_op != &io_uring_fops)
|
|
return -EINVAL;
|
|
}
|
|
if (ctx->flags & IORING_SETUP_SQPOLL) {
|
|
struct task_struct *tsk;
|
|
struct io_sq_data *sqd;
|
|
bool attached;
|
|
|
|
sqd = io_get_sq_data(p, &attached);
|
|
if (IS_ERR(sqd)) {
|
|
ret = PTR_ERR(sqd);
|
|
goto err;
|
|
}
|
|
|
|
ctx->sq_creds = get_current_cred();
|
|
ctx->sq_data = sqd;
|
|
ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
|
|
if (!ctx->sq_thread_idle)
|
|
ctx->sq_thread_idle = HZ;
|
|
|
|
io_sq_thread_park(sqd);
|
|
list_add(&ctx->sqd_list, &sqd->ctx_list);
|
|
io_sqd_update_thread_idle(sqd);
|
|
/* don't attach to a dying SQPOLL thread, would be racy */
|
|
ret = (attached && !sqd->thread) ? -ENXIO : 0;
|
|
io_sq_thread_unpark(sqd);
|
|
|
|
if (ret < 0)
|
|
goto err;
|
|
if (attached)
|
|
return 0;
|
|
|
|
if (p->flags & IORING_SETUP_SQ_AFF) {
|
|
int cpu = p->sq_thread_cpu;
|
|
|
|
ret = -EINVAL;
|
|
if (cpu >= nr_cpu_ids || !cpu_online(cpu))
|
|
goto err_sqpoll;
|
|
sqd->sq_cpu = cpu;
|
|
} else {
|
|
sqd->sq_cpu = -1;
|
|
}
|
|
|
|
sqd->task_pid = current->pid;
|
|
sqd->task_tgid = current->tgid;
|
|
tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
|
|
if (IS_ERR(tsk)) {
|
|
ret = PTR_ERR(tsk);
|
|
goto err_sqpoll;
|
|
}
|
|
|
|
sqd->thread = tsk;
|
|
ret = io_uring_alloc_task_context(tsk, ctx);
|
|
wake_up_new_task(tsk);
|
|
if (ret)
|
|
goto err;
|
|
} else if (p->flags & IORING_SETUP_SQ_AFF) {
|
|
/* Can't have SQ_AFF without SQPOLL */
|
|
ret = -EINVAL;
|
|
goto err;
|
|
}
|
|
|
|
return 0;
|
|
err_sqpoll:
|
|
complete(&ctx->sq_data->exited);
|
|
err:
|
|
io_sq_thread_finish(ctx);
|
|
return ret;
|
|
}
|
|
|
|
static inline void __io_unaccount_mem(struct user_struct *user,
|
|
unsigned long nr_pages)
|
|
{
|
|
atomic_long_sub(nr_pages, &user->locked_vm);
|
|
}
|
|
|
|
static inline int __io_account_mem(struct user_struct *user,
|
|
unsigned long nr_pages)
|
|
{
|
|
unsigned long page_limit, cur_pages, new_pages;
|
|
|
|
/* Don't allow more pages than we can safely lock */
|
|
page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
|
|
|
|
do {
|
|
cur_pages = atomic_long_read(&user->locked_vm);
|
|
new_pages = cur_pages + nr_pages;
|
|
if (new_pages > page_limit)
|
|
return -ENOMEM;
|
|
} while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
|
|
new_pages) != cur_pages);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
|
|
{
|
|
if (ctx->user)
|
|
__io_unaccount_mem(ctx->user, nr_pages);
|
|
|
|
if (ctx->mm_account)
|
|
atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
|
|
}
|
|
|
|
static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
|
|
{
|
|
int ret;
|
|
|
|
if (ctx->user) {
|
|
ret = __io_account_mem(ctx->user, nr_pages);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
if (ctx->mm_account)
|
|
atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void io_mem_free(void *ptr)
|
|
{
|
|
struct page *page;
|
|
|
|
if (!ptr)
|
|
return;
|
|
|
|
page = virt_to_head_page(ptr);
|
|
if (put_page_testzero(page))
|
|
free_compound_page(page);
|
|
}
|
|
|
|
static void *io_mem_alloc(size_t size)
|
|
{
|
|
gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
|
|
__GFP_NORETRY | __GFP_ACCOUNT;
|
|
|
|
return (void *) __get_free_pages(gfp_flags, get_order(size));
|
|
}
|
|
|
|
static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
|
|
size_t *sq_offset)
|
|
{
|
|
struct io_rings *rings;
|
|
size_t off, sq_array_size;
|
|
|
|
off = struct_size(rings, cqes, cq_entries);
|
|
if (off == SIZE_MAX)
|
|
return SIZE_MAX;
|
|
|
|
#ifdef CONFIG_SMP
|
|
off = ALIGN(off, SMP_CACHE_BYTES);
|
|
if (off == 0)
|
|
return SIZE_MAX;
|
|
#endif
|
|
|
|
if (sq_offset)
|
|
*sq_offset = off;
|
|
|
|
sq_array_size = array_size(sizeof(u32), sq_entries);
|
|
if (sq_array_size == SIZE_MAX)
|
|
return SIZE_MAX;
|
|
|
|
if (check_add_overflow(off, sq_array_size, &off))
|
|
return SIZE_MAX;
|
|
|
|
return off;
|
|
}
|
|
|
|
static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
|
|
{
|
|
struct io_mapped_ubuf *imu = *slot;
|
|
unsigned int i;
|
|
|
|
if (imu != ctx->dummy_ubuf) {
|
|
for (i = 0; i < imu->nr_bvecs; i++)
|
|
unpin_user_page(imu->bvec[i].bv_page);
|
|
if (imu->acct_pages)
|
|
io_unaccount_mem(ctx, imu->acct_pages);
|
|
kvfree(imu);
|
|
}
|
|
*slot = NULL;
|
|
}
|
|
|
|
static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
|
|
{
|
|
io_buffer_unmap(ctx, &prsrc->buf);
|
|
prsrc->buf = NULL;
|
|
}
|
|
|
|
static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < ctx->nr_user_bufs; i++)
|
|
io_buffer_unmap(ctx, &ctx->user_bufs[i]);
|
|
kfree(ctx->user_bufs);
|
|
io_rsrc_data_free(ctx->buf_data);
|
|
ctx->user_bufs = NULL;
|
|
ctx->buf_data = NULL;
|
|
ctx->nr_user_bufs = 0;
|
|
}
|
|
|
|
static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
|
|
{
|
|
int ret;
|
|
|
|
if (!ctx->buf_data)
|
|
return -ENXIO;
|
|
|
|
ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
|
|
if (!ret)
|
|
__io_sqe_buffers_unregister(ctx);
|
|
return ret;
|
|
}
|
|
|
|
static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
|
|
void __user *arg, unsigned index)
|
|
{
|
|
struct iovec __user *src;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (ctx->compat) {
|
|
struct compat_iovec __user *ciovs;
|
|
struct compat_iovec ciov;
|
|
|
|
ciovs = (struct compat_iovec __user *) arg;
|
|
if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
|
|
return -EFAULT;
|
|
|
|
dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
|
|
dst->iov_len = ciov.iov_len;
|
|
return 0;
|
|
}
|
|
#endif
|
|
src = (struct iovec __user *) arg;
|
|
if (copy_from_user(dst, &src[index], sizeof(*dst)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Not super efficient, but this is just a registration time. And we do cache
|
|
* the last compound head, so generally we'll only do a full search if we don't
|
|
* match that one.
|
|
*
|
|
* We check if the given compound head page has already been accounted, to
|
|
* avoid double accounting it. This allows us to account the full size of the
|
|
* page, not just the constituent pages of a huge page.
|
|
*/
|
|
static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
|
|
int nr_pages, struct page *hpage)
|
|
{
|
|
int i, j;
|
|
|
|
/* check current page array */
|
|
for (i = 0; i < nr_pages; i++) {
|
|
if (!PageCompound(pages[i]))
|
|
continue;
|
|
if (compound_head(pages[i]) == hpage)
|
|
return true;
|
|
}
|
|
|
|
/* check previously registered pages */
|
|
for (i = 0; i < ctx->nr_user_bufs; i++) {
|
|
struct io_mapped_ubuf *imu = ctx->user_bufs[i];
|
|
|
|
for (j = 0; j < imu->nr_bvecs; j++) {
|
|
if (!PageCompound(imu->bvec[j].bv_page))
|
|
continue;
|
|
if (compound_head(imu->bvec[j].bv_page) == hpage)
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
|
|
int nr_pages, struct io_mapped_ubuf *imu,
|
|
struct page **last_hpage)
|
|
{
|
|
int i, ret;
|
|
|
|
imu->acct_pages = 0;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
if (!PageCompound(pages[i])) {
|
|
imu->acct_pages++;
|
|
} else {
|
|
struct page *hpage;
|
|
|
|
hpage = compound_head(pages[i]);
|
|
if (hpage == *last_hpage)
|
|
continue;
|
|
*last_hpage = hpage;
|
|
if (headpage_already_acct(ctx, pages, i, hpage))
|
|
continue;
|
|
imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
|
|
}
|
|
}
|
|
|
|
if (!imu->acct_pages)
|
|
return 0;
|
|
|
|
ret = io_account_mem(ctx, imu->acct_pages);
|
|
if (ret)
|
|
imu->acct_pages = 0;
|
|
return ret;
|
|
}
|
|
|
|
static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
|
|
struct io_mapped_ubuf **pimu,
|
|
struct page **last_hpage)
|
|
{
|
|
struct io_mapped_ubuf *imu = NULL;
|
|
struct vm_area_struct **vmas = NULL;
|
|
struct page **pages = NULL;
|
|
unsigned long off, start, end, ubuf;
|
|
size_t size;
|
|
int ret, pret, nr_pages, i;
|
|
|
|
if (!iov->iov_base) {
|
|
*pimu = ctx->dummy_ubuf;
|
|
return 0;
|
|
}
|
|
|
|
ubuf = (unsigned long) iov->iov_base;
|
|
end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
start = ubuf >> PAGE_SHIFT;
|
|
nr_pages = end - start;
|
|
|
|
*pimu = NULL;
|
|
ret = -ENOMEM;
|
|
|
|
pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
|
|
if (!pages)
|
|
goto done;
|
|
|
|
vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
|
|
GFP_KERNEL);
|
|
if (!vmas)
|
|
goto done;
|
|
|
|
imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
|
|
if (!imu)
|
|
goto done;
|
|
|
|
ret = 0;
|
|
mmap_read_lock(current->mm);
|
|
pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
|
|
pages, vmas);
|
|
if (pret == nr_pages) {
|
|
/* don't support file backed memory */
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct vm_area_struct *vma = vmas[i];
|
|
|
|
if (vma_is_shmem(vma))
|
|
continue;
|
|
if (vma->vm_file &&
|
|
!is_file_hugepages(vma->vm_file)) {
|
|
ret = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
ret = pret < 0 ? pret : -EFAULT;
|
|
}
|
|
mmap_read_unlock(current->mm);
|
|
if (ret) {
|
|
/*
|
|
* if we did partial map, or found file backed vmas,
|
|
* release any pages we did get
|
|
*/
|
|
if (pret > 0)
|
|
unpin_user_pages(pages, pret);
|
|
goto done;
|
|
}
|
|
|
|
ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
|
|
if (ret) {
|
|
unpin_user_pages(pages, pret);
|
|
goto done;
|
|
}
|
|
|
|
off = ubuf & ~PAGE_MASK;
|
|
size = iov->iov_len;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
size_t vec_len;
|
|
|
|
vec_len = min_t(size_t, size, PAGE_SIZE - off);
|
|
imu->bvec[i].bv_page = pages[i];
|
|
imu->bvec[i].bv_len = vec_len;
|
|
imu->bvec[i].bv_offset = off;
|
|
off = 0;
|
|
size -= vec_len;
|
|
}
|
|
/* store original address for later verification */
|
|
imu->ubuf = ubuf;
|
|
imu->ubuf_end = ubuf + iov->iov_len;
|
|
imu->nr_bvecs = nr_pages;
|
|
*pimu = imu;
|
|
ret = 0;
|
|
done:
|
|
if (ret)
|
|
kvfree(imu);
|
|
kvfree(pages);
|
|
kvfree(vmas);
|
|
return ret;
|
|
}
|
|
|
|
static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
|
|
{
|
|
ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
|
|
return ctx->user_bufs ? 0 : -ENOMEM;
|
|
}
|
|
|
|
static int io_buffer_validate(struct iovec *iov)
|
|
{
|
|
unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
|
|
|
|
/*
|
|
* Don't impose further limits on the size and buffer
|
|
* constraints here, we'll -EINVAL later when IO is
|
|
* submitted if they are wrong.
|
|
*/
|
|
if (!iov->iov_base)
|
|
return iov->iov_len ? -EFAULT : 0;
|
|
if (!iov->iov_len)
|
|
return -EFAULT;
|
|
|
|
/* arbitrary limit, but we need something */
|
|
if (iov->iov_len > SZ_1G)
|
|
return -EFAULT;
|
|
|
|
if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
|
|
return -EOVERFLOW;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned int nr_args, u64 __user *tags)
|
|
{
|
|
struct page *last_hpage = NULL;
|
|
struct io_rsrc_data *data;
|
|
int i, ret;
|
|
struct iovec iov;
|
|
|
|
if (ctx->user_bufs)
|
|
return -EBUSY;
|
|
if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
|
|
return -EINVAL;
|
|
ret = io_rsrc_node_switch_start(ctx);
|
|
if (ret)
|
|
return ret;
|
|
ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
|
|
if (ret)
|
|
return ret;
|
|
ret = io_buffers_map_alloc(ctx, nr_args);
|
|
if (ret) {
|
|
io_rsrc_data_free(data);
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
|
|
ret = io_copy_iov(ctx, &iov, arg, i);
|
|
if (ret)
|
|
break;
|
|
ret = io_buffer_validate(&iov);
|
|
if (ret)
|
|
break;
|
|
if (!iov.iov_base && *io_get_tag_slot(data, i)) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
|
|
&last_hpage);
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
WARN_ON_ONCE(ctx->buf_data);
|
|
|
|
ctx->buf_data = data;
|
|
if (ret)
|
|
__io_sqe_buffers_unregister(ctx);
|
|
else
|
|
io_rsrc_node_switch(ctx, NULL);
|
|
return ret;
|
|
}
|
|
|
|
static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
|
|
struct io_uring_rsrc_update2 *up,
|
|
unsigned int nr_args)
|
|
{
|
|
u64 __user *tags = u64_to_user_ptr(up->tags);
|
|
struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
|
|
struct page *last_hpage = NULL;
|
|
bool needs_switch = false;
|
|
__u32 done;
|
|
int i, err;
|
|
|
|
if (!ctx->buf_data)
|
|
return -ENXIO;
|
|
if (up->offset + nr_args > ctx->nr_user_bufs)
|
|
return -EINVAL;
|
|
|
|
for (done = 0; done < nr_args; done++) {
|
|
struct io_mapped_ubuf *imu;
|
|
int offset = up->offset + done;
|
|
u64 tag = 0;
|
|
|
|
err = io_copy_iov(ctx, &iov, iovs, done);
|
|
if (err)
|
|
break;
|
|
if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
err = io_buffer_validate(&iov);
|
|
if (err)
|
|
break;
|
|
if (!iov.iov_base && tag) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
|
|
if (err)
|
|
break;
|
|
|
|
i = array_index_nospec(offset, ctx->nr_user_bufs);
|
|
if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
|
|
err = io_queue_rsrc_removal(ctx->buf_data, offset,
|
|
ctx->rsrc_node, ctx->user_bufs[i]);
|
|
if (unlikely(err)) {
|
|
io_buffer_unmap(ctx, &imu);
|
|
break;
|
|
}
|
|
ctx->user_bufs[i] = NULL;
|
|
needs_switch = true;
|
|
}
|
|
|
|
ctx->user_bufs[i] = imu;
|
|
*io_get_tag_slot(ctx->buf_data, offset) = tag;
|
|
}
|
|
|
|
if (needs_switch)
|
|
io_rsrc_node_switch(ctx, ctx->buf_data);
|
|
return done ? done : err;
|
|
}
|
|
|
|
static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
|
|
{
|
|
__s32 __user *fds = arg;
|
|
int fd;
|
|
|
|
if (ctx->cq_ev_fd)
|
|
return -EBUSY;
|
|
|
|
if (copy_from_user(&fd, fds, sizeof(*fds)))
|
|
return -EFAULT;
|
|
|
|
ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
|
|
if (IS_ERR(ctx->cq_ev_fd)) {
|
|
int ret = PTR_ERR(ctx->cq_ev_fd);
|
|
|
|
ctx->cq_ev_fd = NULL;
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_eventfd_unregister(struct io_ring_ctx *ctx)
|
|
{
|
|
if (ctx->cq_ev_fd) {
|
|
eventfd_ctx_put(ctx->cq_ev_fd);
|
|
ctx->cq_ev_fd = NULL;
|
|
return 0;
|
|
}
|
|
|
|
return -ENXIO;
|
|
}
|
|
|
|
static void io_destroy_buffers(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_buffer *buf;
|
|
unsigned long index;
|
|
|
|
xa_for_each(&ctx->io_buffers, index, buf)
|
|
__io_remove_buffers(ctx, buf, index, -1U);
|
|
}
|
|
|
|
static void io_req_cache_free(struct list_head *list, struct task_struct *tsk)
|
|
{
|
|
struct io_kiocb *req, *nxt;
|
|
|
|
list_for_each_entry_safe(req, nxt, list, compl.list) {
|
|
if (tsk && req->task != tsk)
|
|
continue;
|
|
list_del(&req->compl.list);
|
|
kmem_cache_free(req_cachep, req);
|
|
}
|
|
}
|
|
|
|
static void io_req_caches_free(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_submit_state *submit_state = &ctx->submit_state;
|
|
struct io_comp_state *cs = &ctx->submit_state.comp;
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
|
|
if (submit_state->free_reqs) {
|
|
kmem_cache_free_bulk(req_cachep, submit_state->free_reqs,
|
|
submit_state->reqs);
|
|
submit_state->free_reqs = 0;
|
|
}
|
|
|
|
io_flush_cached_locked_reqs(ctx, cs);
|
|
io_req_cache_free(&cs->free_list, NULL);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static bool io_wait_rsrc_data(struct io_rsrc_data *data)
|
|
{
|
|
if (!data)
|
|
return false;
|
|
if (!atomic_dec_and_test(&data->refs))
|
|
wait_for_completion(&data->done);
|
|
return true;
|
|
}
|
|
|
|
static void io_ring_ctx_free(struct io_ring_ctx *ctx)
|
|
{
|
|
io_sq_thread_finish(ctx);
|
|
|
|
if (ctx->mm_account) {
|
|
mmdrop(ctx->mm_account);
|
|
ctx->mm_account = NULL;
|
|
}
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
if (io_wait_rsrc_data(ctx->buf_data))
|
|
__io_sqe_buffers_unregister(ctx);
|
|
if (io_wait_rsrc_data(ctx->file_data))
|
|
__io_sqe_files_unregister(ctx);
|
|
if (ctx->rings)
|
|
__io_cqring_overflow_flush(ctx, true);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
io_eventfd_unregister(ctx);
|
|
io_destroy_buffers(ctx);
|
|
if (ctx->sq_creds)
|
|
put_cred(ctx->sq_creds);
|
|
|
|
/* there are no registered resources left, nobody uses it */
|
|
if (ctx->rsrc_node)
|
|
io_rsrc_node_destroy(ctx->rsrc_node);
|
|
if (ctx->rsrc_backup_node)
|
|
io_rsrc_node_destroy(ctx->rsrc_backup_node);
|
|
flush_delayed_work(&ctx->rsrc_put_work);
|
|
|
|
WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
|
|
WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
|
|
|
|
#if defined(CONFIG_UNIX)
|
|
if (ctx->ring_sock) {
|
|
ctx->ring_sock->file = NULL; /* so that iput() is called */
|
|
sock_release(ctx->ring_sock);
|
|
}
|
|
#endif
|
|
|
|
io_mem_free(ctx->rings);
|
|
io_mem_free(ctx->sq_sqes);
|
|
|
|
percpu_ref_exit(&ctx->refs);
|
|
free_uid(ctx->user);
|
|
io_req_caches_free(ctx);
|
|
if (ctx->hash_map)
|
|
io_wq_put_hash(ctx->hash_map);
|
|
kfree(ctx->cancel_hash);
|
|
kfree(ctx->dummy_ubuf);
|
|
kfree(ctx);
|
|
}
|
|
|
|
static __poll_t io_uring_poll(struct file *file, poll_table *wait)
|
|
{
|
|
struct io_ring_ctx *ctx = file->private_data;
|
|
__poll_t mask = 0;
|
|
|
|
poll_wait(file, &ctx->poll_wait, wait);
|
|
/*
|
|
* synchronizes with barrier from wq_has_sleeper call in
|
|
* io_commit_cqring
|
|
*/
|
|
smp_rmb();
|
|
if (!io_sqring_full(ctx))
|
|
mask |= EPOLLOUT | EPOLLWRNORM;
|
|
|
|
/*
|
|
* Don't flush cqring overflow list here, just do a simple check.
|
|
* Otherwise there could possible be ABBA deadlock:
|
|
* CPU0 CPU1
|
|
* ---- ----
|
|
* lock(&ctx->uring_lock);
|
|
* lock(&ep->mtx);
|
|
* lock(&ctx->uring_lock);
|
|
* lock(&ep->mtx);
|
|
*
|
|
* Users may get EPOLLIN meanwhile seeing nothing in cqring, this
|
|
* pushs them to do the flush.
|
|
*/
|
|
if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
|
|
mask |= EPOLLIN | EPOLLRDNORM;
|
|
|
|
return mask;
|
|
}
|
|
|
|
static int io_uring_fasync(int fd, struct file *file, int on)
|
|
{
|
|
struct io_ring_ctx *ctx = file->private_data;
|
|
|
|
return fasync_helper(fd, file, on, &ctx->cq_fasync);
|
|
}
|
|
|
|
static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
|
|
{
|
|
const struct cred *creds;
|
|
|
|
creds = xa_erase(&ctx->personalities, id);
|
|
if (creds) {
|
|
put_cred(creds);
|
|
return 0;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct io_tctx_exit {
|
|
struct callback_head task_work;
|
|
struct completion completion;
|
|
struct io_ring_ctx *ctx;
|
|
};
|
|
|
|
static void io_tctx_exit_cb(struct callback_head *cb)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
struct io_tctx_exit *work;
|
|
|
|
work = container_of(cb, struct io_tctx_exit, task_work);
|
|
/*
|
|
* When @in_idle, we're in cancellation and it's racy to remove the
|
|
* node. It'll be removed by the end of cancellation, just ignore it.
|
|
*/
|
|
if (!atomic_read(&tctx->in_idle))
|
|
io_uring_del_tctx_node((unsigned long)work->ctx);
|
|
complete(&work->completion);
|
|
}
|
|
|
|
static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
|
|
{
|
|
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
|
|
|
|
return req->ctx == data;
|
|
}
|
|
|
|
static void io_ring_exit_work(struct work_struct *work)
|
|
{
|
|
struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
|
|
unsigned long timeout = jiffies + HZ * 60 * 5;
|
|
struct io_tctx_exit exit;
|
|
struct io_tctx_node *node;
|
|
int ret;
|
|
|
|
/*
|
|
* If we're doing polled IO and end up having requests being
|
|
* submitted async (out-of-line), then completions can come in while
|
|
* we're waiting for refs to drop. We need to reap these manually,
|
|
* as nobody else will be looking for them.
|
|
*/
|
|
do {
|
|
io_uring_try_cancel_requests(ctx, NULL, true);
|
|
if (ctx->sq_data) {
|
|
struct io_sq_data *sqd = ctx->sq_data;
|
|
struct task_struct *tsk;
|
|
|
|
io_sq_thread_park(sqd);
|
|
tsk = sqd->thread;
|
|
if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
|
|
io_wq_cancel_cb(tsk->io_uring->io_wq,
|
|
io_cancel_ctx_cb, ctx, true);
|
|
io_sq_thread_unpark(sqd);
|
|
}
|
|
|
|
WARN_ON_ONCE(time_after(jiffies, timeout));
|
|
} while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20));
|
|
|
|
init_completion(&exit.completion);
|
|
init_task_work(&exit.task_work, io_tctx_exit_cb);
|
|
exit.ctx = ctx;
|
|
/*
|
|
* Some may use context even when all refs and requests have been put,
|
|
* and they are free to do so while still holding uring_lock or
|
|
* completion_lock, see io_req_task_submit(). Apart from other work,
|
|
* this lock/unlock section also waits them to finish.
|
|
*/
|
|
mutex_lock(&ctx->uring_lock);
|
|
while (!list_empty(&ctx->tctx_list)) {
|
|
WARN_ON_ONCE(time_after(jiffies, timeout));
|
|
|
|
node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
|
|
ctx_node);
|
|
/* don't spin on a single task if cancellation failed */
|
|
list_rotate_left(&ctx->tctx_list);
|
|
ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
|
|
if (WARN_ON_ONCE(ret))
|
|
continue;
|
|
wake_up_process(node->task);
|
|
|
|
mutex_unlock(&ctx->uring_lock);
|
|
wait_for_completion(&exit.completion);
|
|
mutex_lock(&ctx->uring_lock);
|
|
}
|
|
mutex_unlock(&ctx->uring_lock);
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
|
|
io_ring_ctx_free(ctx);
|
|
}
|
|
|
|
/* Returns true if we found and killed one or more timeouts */
|
|
static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
|
|
bool cancel_all)
|
|
{
|
|
struct io_kiocb *req, *tmp;
|
|
int canceled = 0;
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
|
|
if (io_match_task(req, tsk, cancel_all)) {
|
|
io_kill_timeout(req, -ECANCELED);
|
|
canceled++;
|
|
}
|
|
}
|
|
if (canceled != 0)
|
|
io_commit_cqring(ctx);
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
if (canceled != 0)
|
|
io_cqring_ev_posted(ctx);
|
|
return canceled != 0;
|
|
}
|
|
|
|
static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
|
|
{
|
|
unsigned long index;
|
|
struct creds *creds;
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
percpu_ref_kill(&ctx->refs);
|
|
if (ctx->rings)
|
|
__io_cqring_overflow_flush(ctx, true);
|
|
xa_for_each(&ctx->personalities, index, creds)
|
|
io_unregister_personality(ctx, index);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
|
|
io_kill_timeouts(ctx, NULL, true);
|
|
io_poll_remove_all(ctx, NULL, true);
|
|
|
|
/* if we failed setting up the ctx, we might not have any rings */
|
|
io_iopoll_try_reap_events(ctx);
|
|
|
|
INIT_WORK(&ctx->exit_work, io_ring_exit_work);
|
|
/*
|
|
* Use system_unbound_wq to avoid spawning tons of event kworkers
|
|
* if we're exiting a ton of rings at the same time. It just adds
|
|
* noise and overhead, there's no discernable change in runtime
|
|
* over using system_wq.
|
|
*/
|
|
queue_work(system_unbound_wq, &ctx->exit_work);
|
|
}
|
|
|
|
static int io_uring_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct io_ring_ctx *ctx = file->private_data;
|
|
|
|
file->private_data = NULL;
|
|
io_ring_ctx_wait_and_kill(ctx);
|
|
return 0;
|
|
}
|
|
|
|
struct io_task_cancel {
|
|
struct task_struct *task;
|
|
bool all;
|
|
};
|
|
|
|
static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
|
|
{
|
|
struct io_kiocb *req = container_of(work, struct io_kiocb, work);
|
|
struct io_task_cancel *cancel = data;
|
|
bool ret;
|
|
|
|
if (!cancel->all && (req->flags & REQ_F_LINK_TIMEOUT)) {
|
|
unsigned long flags;
|
|
struct io_ring_ctx *ctx = req->ctx;
|
|
|
|
/* protect against races with linked timeouts */
|
|
spin_lock_irqsave(&ctx->completion_lock, flags);
|
|
ret = io_match_task(req, cancel->task, cancel->all);
|
|
spin_unlock_irqrestore(&ctx->completion_lock, flags);
|
|
} else {
|
|
ret = io_match_task(req, cancel->task, cancel->all);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
|
|
struct task_struct *task, bool cancel_all)
|
|
{
|
|
struct io_defer_entry *de;
|
|
LIST_HEAD(list);
|
|
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
list_for_each_entry_reverse(de, &ctx->defer_list, list) {
|
|
if (io_match_task(de->req, task, cancel_all)) {
|
|
list_cut_position(&list, &ctx->defer_list, &de->list);
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
if (list_empty(&list))
|
|
return false;
|
|
|
|
while (!list_empty(&list)) {
|
|
de = list_first_entry(&list, struct io_defer_entry, list);
|
|
list_del_init(&de->list);
|
|
io_req_complete_failed(de->req, -ECANCELED);
|
|
kfree(de);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_tctx_node *node;
|
|
enum io_wq_cancel cret;
|
|
bool ret = false;
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
|
|
struct io_uring_task *tctx = node->task->io_uring;
|
|
|
|
/*
|
|
* io_wq will stay alive while we hold uring_lock, because it's
|
|
* killed after ctx nodes, which requires to take the lock.
|
|
*/
|
|
if (!tctx || !tctx->io_wq)
|
|
continue;
|
|
cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
|
|
ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
|
|
}
|
|
mutex_unlock(&ctx->uring_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
|
|
struct task_struct *task,
|
|
bool cancel_all)
|
|
{
|
|
struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
|
|
struct io_uring_task *tctx = task ? task->io_uring : NULL;
|
|
|
|
while (1) {
|
|
enum io_wq_cancel cret;
|
|
bool ret = false;
|
|
|
|
if (!task) {
|
|
ret |= io_uring_try_cancel_iowq(ctx);
|
|
} else if (tctx && tctx->io_wq) {
|
|
/*
|
|
* Cancels requests of all rings, not only @ctx, but
|
|
* it's fine as the task is in exit/exec.
|
|
*/
|
|
cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
|
|
&cancel, true);
|
|
ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
|
|
}
|
|
|
|
/* SQPOLL thread does its own polling */
|
|
if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
|
|
(ctx->sq_data && ctx->sq_data->thread == current)) {
|
|
while (!list_empty_careful(&ctx->iopoll_list)) {
|
|
io_iopoll_try_reap_events(ctx);
|
|
ret = true;
|
|
}
|
|
}
|
|
|
|
ret |= io_cancel_defer_files(ctx, task, cancel_all);
|
|
ret |= io_poll_remove_all(ctx, task, cancel_all);
|
|
ret |= io_kill_timeouts(ctx, task, cancel_all);
|
|
if (task)
|
|
ret |= io_run_task_work();
|
|
if (!ret)
|
|
break;
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
struct io_tctx_node *node;
|
|
int ret;
|
|
|
|
if (unlikely(!tctx)) {
|
|
ret = io_uring_alloc_task_context(current, ctx);
|
|
if (unlikely(ret))
|
|
return ret;
|
|
tctx = current->io_uring;
|
|
}
|
|
if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
|
|
node = kmalloc(sizeof(*node), GFP_KERNEL);
|
|
if (!node)
|
|
return -ENOMEM;
|
|
node->ctx = ctx;
|
|
node->task = current;
|
|
|
|
ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
|
|
node, GFP_KERNEL));
|
|
if (ret) {
|
|
kfree(node);
|
|
return ret;
|
|
}
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
list_add(&node->ctx_node, &ctx->tctx_list);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
tctx->last = ctx;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Note that this task has used io_uring. We use it for cancelation purposes.
|
|
*/
|
|
static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
|
|
if (likely(tctx && tctx->last == ctx))
|
|
return 0;
|
|
return __io_uring_add_tctx_node(ctx);
|
|
}
|
|
|
|
/*
|
|
* Remove this io_uring_file -> task mapping.
|
|
*/
|
|
static void io_uring_del_tctx_node(unsigned long index)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
struct io_tctx_node *node;
|
|
|
|
if (!tctx)
|
|
return;
|
|
node = xa_erase(&tctx->xa, index);
|
|
if (!node)
|
|
return;
|
|
|
|
WARN_ON_ONCE(current != node->task);
|
|
WARN_ON_ONCE(list_empty(&node->ctx_node));
|
|
|
|
mutex_lock(&node->ctx->uring_lock);
|
|
list_del(&node->ctx_node);
|
|
mutex_unlock(&node->ctx->uring_lock);
|
|
|
|
if (tctx->last == node->ctx)
|
|
tctx->last = NULL;
|
|
kfree(node);
|
|
}
|
|
|
|
static void io_uring_clean_tctx(struct io_uring_task *tctx)
|
|
{
|
|
struct io_wq *wq = tctx->io_wq;
|
|
struct io_tctx_node *node;
|
|
unsigned long index;
|
|
|
|
xa_for_each(&tctx->xa, index, node)
|
|
io_uring_del_tctx_node(index);
|
|
if (wq) {
|
|
/*
|
|
* Must be after io_uring_del_task_file() (removes nodes under
|
|
* uring_lock) to avoid race with io_uring_try_cancel_iowq().
|
|
*/
|
|
tctx->io_wq = NULL;
|
|
io_wq_put_and_exit(wq);
|
|
}
|
|
}
|
|
|
|
static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
|
|
{
|
|
if (tracked)
|
|
return atomic_read(&tctx->inflight_tracked);
|
|
return percpu_counter_sum(&tctx->inflight);
|
|
}
|
|
|
|
static void io_uring_drop_tctx_refs(struct task_struct *task)
|
|
{
|
|
struct io_uring_task *tctx = task->io_uring;
|
|
unsigned int refs = tctx->cached_refs;
|
|
|
|
tctx->cached_refs = 0;
|
|
percpu_counter_sub(&tctx->inflight, refs);
|
|
put_task_struct_many(task, refs);
|
|
}
|
|
|
|
/*
|
|
* Find any io_uring ctx that this task has registered or done IO on, and cancel
|
|
* requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
|
|
*/
|
|
static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
struct io_ring_ctx *ctx;
|
|
s64 inflight;
|
|
DEFINE_WAIT(wait);
|
|
|
|
WARN_ON_ONCE(sqd && sqd->thread != current);
|
|
|
|
if (!current->io_uring)
|
|
return;
|
|
if (tctx->io_wq)
|
|
io_wq_exit_start(tctx->io_wq);
|
|
|
|
io_uring_drop_tctx_refs(current);
|
|
atomic_inc(&tctx->in_idle);
|
|
do {
|
|
/* read completions before cancelations */
|
|
inflight = tctx_inflight(tctx, !cancel_all);
|
|
if (!inflight)
|
|
break;
|
|
|
|
if (!sqd) {
|
|
struct io_tctx_node *node;
|
|
unsigned long index;
|
|
|
|
xa_for_each(&tctx->xa, index, node) {
|
|
/* sqpoll task will cancel all its requests */
|
|
if (node->ctx->sq_data)
|
|
continue;
|
|
io_uring_try_cancel_requests(node->ctx, current,
|
|
cancel_all);
|
|
}
|
|
} else {
|
|
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
|
|
io_uring_try_cancel_requests(ctx, current,
|
|
cancel_all);
|
|
}
|
|
|
|
prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
|
|
/*
|
|
* If we've seen completions, retry without waiting. This
|
|
* avoids a race where a completion comes in before we did
|
|
* prepare_to_wait().
|
|
*/
|
|
if (inflight == tctx_inflight(tctx, !cancel_all))
|
|
schedule();
|
|
finish_wait(&tctx->wait, &wait);
|
|
} while (1);
|
|
atomic_dec(&tctx->in_idle);
|
|
|
|
io_uring_clean_tctx(tctx);
|
|
if (cancel_all) {
|
|
/* for exec all current's requests should be gone, kill tctx */
|
|
__io_uring_free(current);
|
|
}
|
|
}
|
|
|
|
void __io_uring_cancel(struct files_struct *files)
|
|
{
|
|
io_uring_cancel_generic(!files, NULL);
|
|
}
|
|
|
|
static void *io_uring_validate_mmap_request(struct file *file,
|
|
loff_t pgoff, size_t sz)
|
|
{
|
|
struct io_ring_ctx *ctx = file->private_data;
|
|
loff_t offset = pgoff << PAGE_SHIFT;
|
|
struct page *page;
|
|
void *ptr;
|
|
|
|
switch (offset) {
|
|
case IORING_OFF_SQ_RING:
|
|
case IORING_OFF_CQ_RING:
|
|
ptr = ctx->rings;
|
|
break;
|
|
case IORING_OFF_SQES:
|
|
ptr = ctx->sq_sqes;
|
|
break;
|
|
default:
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
page = virt_to_head_page(ptr);
|
|
if (sz > page_size(page))
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
return ptr;
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
size_t sz = vma->vm_end - vma->vm_start;
|
|
unsigned long pfn;
|
|
void *ptr;
|
|
|
|
ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
|
|
if (IS_ERR(ptr))
|
|
return PTR_ERR(ptr);
|
|
|
|
pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
|
|
return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
|
|
}
|
|
|
|
#else /* !CONFIG_MMU */
|
|
|
|
static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
|
|
}
|
|
|
|
static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
|
|
{
|
|
return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
|
|
}
|
|
|
|
static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
|
|
unsigned long addr, unsigned long len,
|
|
unsigned long pgoff, unsigned long flags)
|
|
{
|
|
void *ptr;
|
|
|
|
ptr = io_uring_validate_mmap_request(file, pgoff, len);
|
|
if (IS_ERR(ptr))
|
|
return PTR_ERR(ptr);
|
|
|
|
return (unsigned long) ptr;
|
|
}
|
|
|
|
#endif /* !CONFIG_MMU */
|
|
|
|
static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
|
|
{
|
|
DEFINE_WAIT(wait);
|
|
|
|
do {
|
|
if (!io_sqring_full(ctx))
|
|
break;
|
|
prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
|
|
|
|
if (!io_sqring_full(ctx))
|
|
break;
|
|
schedule();
|
|
} while (!signal_pending(current));
|
|
|
|
finish_wait(&ctx->sqo_sq_wait, &wait);
|
|
return 0;
|
|
}
|
|
|
|
static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
|
|
struct __kernel_timespec __user **ts,
|
|
const sigset_t __user **sig)
|
|
{
|
|
struct io_uring_getevents_arg arg;
|
|
|
|
/*
|
|
* If EXT_ARG isn't set, then we have no timespec and the argp pointer
|
|
* is just a pointer to the sigset_t.
|
|
*/
|
|
if (!(flags & IORING_ENTER_EXT_ARG)) {
|
|
*sig = (const sigset_t __user *) argp;
|
|
*ts = NULL;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* EXT_ARG is set - ensure we agree on the size of it and copy in our
|
|
* timespec and sigset_t pointers if good.
|
|
*/
|
|
if (*argsz != sizeof(arg))
|
|
return -EINVAL;
|
|
if (copy_from_user(&arg, argp, sizeof(arg)))
|
|
return -EFAULT;
|
|
*sig = u64_to_user_ptr(arg.sigmask);
|
|
*argsz = arg.sigmask_sz;
|
|
*ts = u64_to_user_ptr(arg.ts);
|
|
return 0;
|
|
}
|
|
|
|
SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
|
|
u32, min_complete, u32, flags, const void __user *, argp,
|
|
size_t, argsz)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
int submitted = 0;
|
|
struct fd f;
|
|
long ret;
|
|
|
|
io_run_task_work();
|
|
|
|
if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
|
|
IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
|
|
return -EINVAL;
|
|
|
|
f = fdget(fd);
|
|
if (unlikely(!f.file))
|
|
return -EBADF;
|
|
|
|
ret = -EOPNOTSUPP;
|
|
if (unlikely(f.file->f_op != &io_uring_fops))
|
|
goto out_fput;
|
|
|
|
ret = -ENXIO;
|
|
ctx = f.file->private_data;
|
|
if (unlikely(!percpu_ref_tryget(&ctx->refs)))
|
|
goto out_fput;
|
|
|
|
ret = -EBADFD;
|
|
if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
|
|
goto out;
|
|
|
|
/*
|
|
* For SQ polling, the thread will do all submissions and completions.
|
|
* Just return the requested submit count, and wake the thread if
|
|
* we were asked to.
|
|
*/
|
|
ret = 0;
|
|
if (ctx->flags & IORING_SETUP_SQPOLL) {
|
|
io_cqring_overflow_flush(ctx, false);
|
|
|
|
ret = -EOWNERDEAD;
|
|
if (unlikely(ctx->sq_data->thread == NULL))
|
|
goto out;
|
|
if (flags & IORING_ENTER_SQ_WAKEUP)
|
|
wake_up(&ctx->sq_data->wait);
|
|
if (flags & IORING_ENTER_SQ_WAIT) {
|
|
ret = io_sqpoll_wait_sq(ctx);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
submitted = to_submit;
|
|
} else if (to_submit) {
|
|
ret = io_uring_add_tctx_node(ctx);
|
|
if (unlikely(ret))
|
|
goto out;
|
|
mutex_lock(&ctx->uring_lock);
|
|
submitted = io_submit_sqes(ctx, to_submit);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
|
|
if (submitted != to_submit)
|
|
goto out;
|
|
}
|
|
if (flags & IORING_ENTER_GETEVENTS) {
|
|
const sigset_t __user *sig;
|
|
struct __kernel_timespec __user *ts;
|
|
|
|
ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
|
|
if (unlikely(ret))
|
|
goto out;
|
|
|
|
min_complete = min(min_complete, ctx->cq_entries);
|
|
|
|
/*
|
|
* When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
|
|
* space applications don't need to do io completion events
|
|
* polling again, they can rely on io_sq_thread to do polling
|
|
* work, which can reduce cpu usage and uring_lock contention.
|
|
*/
|
|
if (ctx->flags & IORING_SETUP_IOPOLL &&
|
|
!(ctx->flags & IORING_SETUP_SQPOLL)) {
|
|
ret = io_iopoll_check(ctx, min_complete);
|
|
} else {
|
|
ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
|
|
}
|
|
}
|
|
|
|
out:
|
|
percpu_ref_put(&ctx->refs);
|
|
out_fput:
|
|
fdput(f);
|
|
return submitted ? submitted : ret;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static int io_uring_show_cred(struct seq_file *m, unsigned int id,
|
|
const struct cred *cred)
|
|
{
|
|
struct user_namespace *uns = seq_user_ns(m);
|
|
struct group_info *gi;
|
|
kernel_cap_t cap;
|
|
unsigned __capi;
|
|
int g;
|
|
|
|
seq_printf(m, "%5d\n", id);
|
|
seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
|
|
seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
|
|
seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
|
|
seq_puts(m, "\n\tGroups:\t");
|
|
gi = cred->group_info;
|
|
for (g = 0; g < gi->ngroups; g++) {
|
|
seq_put_decimal_ull(m, g ? " " : "",
|
|
from_kgid_munged(uns, gi->gid[g]));
|
|
}
|
|
seq_puts(m, "\n\tCapEff:\t");
|
|
cap = cred->cap_effective;
|
|
CAP_FOR_EACH_U32(__capi)
|
|
seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
|
|
seq_putc(m, '\n');
|
|
return 0;
|
|
}
|
|
|
|
static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
|
|
{
|
|
struct io_sq_data *sq = NULL;
|
|
bool has_lock;
|
|
int i;
|
|
|
|
/*
|
|
* Avoid ABBA deadlock between the seq lock and the io_uring mutex,
|
|
* since fdinfo case grabs it in the opposite direction of normal use
|
|
* cases. If we fail to get the lock, we just don't iterate any
|
|
* structures that could be going away outside the io_uring mutex.
|
|
*/
|
|
has_lock = mutex_trylock(&ctx->uring_lock);
|
|
|
|
if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
|
|
sq = ctx->sq_data;
|
|
if (!sq->thread)
|
|
sq = NULL;
|
|
}
|
|
|
|
seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
|
|
seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
|
|
seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
|
|
for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
|
|
struct file *f = io_file_from_index(ctx, i);
|
|
|
|
if (f)
|
|
seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
|
|
else
|
|
seq_printf(m, "%5u: <none>\n", i);
|
|
}
|
|
seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
|
|
for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
|
|
struct io_mapped_ubuf *buf = ctx->user_bufs[i];
|
|
unsigned int len = buf->ubuf_end - buf->ubuf;
|
|
|
|
seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
|
|
}
|
|
if (has_lock && !xa_empty(&ctx->personalities)) {
|
|
unsigned long index;
|
|
const struct cred *cred;
|
|
|
|
seq_printf(m, "Personalities:\n");
|
|
xa_for_each(&ctx->personalities, index, cred)
|
|
io_uring_show_cred(m, index, cred);
|
|
}
|
|
seq_printf(m, "PollList:\n");
|
|
spin_lock_irq(&ctx->completion_lock);
|
|
for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
|
|
struct hlist_head *list = &ctx->cancel_hash[i];
|
|
struct io_kiocb *req;
|
|
|
|
hlist_for_each_entry(req, list, hash_node)
|
|
seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
|
|
req->task->task_works != NULL);
|
|
}
|
|
spin_unlock_irq(&ctx->completion_lock);
|
|
if (has_lock)
|
|
mutex_unlock(&ctx->uring_lock);
|
|
}
|
|
|
|
static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
|
|
{
|
|
struct io_ring_ctx *ctx = f->private_data;
|
|
|
|
if (percpu_ref_tryget(&ctx->refs)) {
|
|
__io_uring_show_fdinfo(ctx, m);
|
|
percpu_ref_put(&ctx->refs);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
static const struct file_operations io_uring_fops = {
|
|
.release = io_uring_release,
|
|
.mmap = io_uring_mmap,
|
|
#ifndef CONFIG_MMU
|
|
.get_unmapped_area = io_uring_nommu_get_unmapped_area,
|
|
.mmap_capabilities = io_uring_nommu_mmap_capabilities,
|
|
#endif
|
|
.poll = io_uring_poll,
|
|
.fasync = io_uring_fasync,
|
|
#ifdef CONFIG_PROC_FS
|
|
.show_fdinfo = io_uring_show_fdinfo,
|
|
#endif
|
|
};
|
|
|
|
static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
|
|
struct io_uring_params *p)
|
|
{
|
|
struct io_rings *rings;
|
|
size_t size, sq_array_offset;
|
|
|
|
/* make sure these are sane, as we already accounted them */
|
|
ctx->sq_entries = p->sq_entries;
|
|
ctx->cq_entries = p->cq_entries;
|
|
|
|
size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
|
|
if (size == SIZE_MAX)
|
|
return -EOVERFLOW;
|
|
|
|
rings = io_mem_alloc(size);
|
|
if (!rings)
|
|
return -ENOMEM;
|
|
|
|
ctx->rings = rings;
|
|
ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
|
|
rings->sq_ring_mask = p->sq_entries - 1;
|
|
rings->cq_ring_mask = p->cq_entries - 1;
|
|
rings->sq_ring_entries = p->sq_entries;
|
|
rings->cq_ring_entries = p->cq_entries;
|
|
|
|
size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
|
|
if (size == SIZE_MAX) {
|
|
io_mem_free(ctx->rings);
|
|
ctx->rings = NULL;
|
|
return -EOVERFLOW;
|
|
}
|
|
|
|
ctx->sq_sqes = io_mem_alloc(size);
|
|
if (!ctx->sq_sqes) {
|
|
io_mem_free(ctx->rings);
|
|
ctx->rings = NULL;
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
|
|
{
|
|
int ret, fd;
|
|
|
|
fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
ret = io_uring_add_tctx_node(ctx);
|
|
if (ret) {
|
|
put_unused_fd(fd);
|
|
return ret;
|
|
}
|
|
fd_install(fd, file);
|
|
return fd;
|
|
}
|
|
|
|
/*
|
|
* Allocate an anonymous fd, this is what constitutes the application
|
|
* visible backing of an io_uring instance. The application mmaps this
|
|
* fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
|
|
* we have to tie this fd to a socket for file garbage collection purposes.
|
|
*/
|
|
static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
|
|
{
|
|
struct file *file;
|
|
#if defined(CONFIG_UNIX)
|
|
int ret;
|
|
|
|
ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
|
|
&ctx->ring_sock);
|
|
if (ret)
|
|
return ERR_PTR(ret);
|
|
#endif
|
|
|
|
file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
|
|
O_RDWR | O_CLOEXEC);
|
|
#if defined(CONFIG_UNIX)
|
|
if (IS_ERR(file)) {
|
|
sock_release(ctx->ring_sock);
|
|
ctx->ring_sock = NULL;
|
|
} else {
|
|
ctx->ring_sock->file = file;
|
|
}
|
|
#endif
|
|
return file;
|
|
}
|
|
|
|
static int io_uring_create(unsigned entries, struct io_uring_params *p,
|
|
struct io_uring_params __user *params)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
struct file *file;
|
|
int ret;
|
|
|
|
if (!entries)
|
|
return -EINVAL;
|
|
if (entries > IORING_MAX_ENTRIES) {
|
|
if (!(p->flags & IORING_SETUP_CLAMP))
|
|
return -EINVAL;
|
|
entries = IORING_MAX_ENTRIES;
|
|
}
|
|
|
|
/*
|
|
* Use twice as many entries for the CQ ring. It's possible for the
|
|
* application to drive a higher depth than the size of the SQ ring,
|
|
* since the sqes are only used at submission time. This allows for
|
|
* some flexibility in overcommitting a bit. If the application has
|
|
* set IORING_SETUP_CQSIZE, it will have passed in the desired number
|
|
* of CQ ring entries manually.
|
|
*/
|
|
p->sq_entries = roundup_pow_of_two(entries);
|
|
if (p->flags & IORING_SETUP_CQSIZE) {
|
|
/*
|
|
* If IORING_SETUP_CQSIZE is set, we do the same roundup
|
|
* to a power-of-two, if it isn't already. We do NOT impose
|
|
* any cq vs sq ring sizing.
|
|
*/
|
|
if (!p->cq_entries)
|
|
return -EINVAL;
|
|
if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
|
|
if (!(p->flags & IORING_SETUP_CLAMP))
|
|
return -EINVAL;
|
|
p->cq_entries = IORING_MAX_CQ_ENTRIES;
|
|
}
|
|
p->cq_entries = roundup_pow_of_two(p->cq_entries);
|
|
if (p->cq_entries < p->sq_entries)
|
|
return -EINVAL;
|
|
} else {
|
|
p->cq_entries = 2 * p->sq_entries;
|
|
}
|
|
|
|
ctx = io_ring_ctx_alloc(p);
|
|
if (!ctx)
|
|
return -ENOMEM;
|
|
ctx->compat = in_compat_syscall();
|
|
if (!capable(CAP_IPC_LOCK))
|
|
ctx->user = get_uid(current_user());
|
|
|
|
/*
|
|
* This is just grabbed for accounting purposes. When a process exits,
|
|
* the mm is exited and dropped before the files, hence we need to hang
|
|
* on to this mm purely for the purposes of being able to unaccount
|
|
* memory (locked/pinned vm). It's not used for anything else.
|
|
*/
|
|
mmgrab(current->mm);
|
|
ctx->mm_account = current->mm;
|
|
|
|
ret = io_allocate_scq_urings(ctx, p);
|
|
if (ret)
|
|
goto err;
|
|
|
|
ret = io_sq_offload_create(ctx, p);
|
|
if (ret)
|
|
goto err;
|
|
/* always set a rsrc node */
|
|
ret = io_rsrc_node_switch_start(ctx);
|
|
if (ret)
|
|
goto err;
|
|
io_rsrc_node_switch(ctx, NULL);
|
|
|
|
memset(&p->sq_off, 0, sizeof(p->sq_off));
|
|
p->sq_off.head = offsetof(struct io_rings, sq.head);
|
|
p->sq_off.tail = offsetof(struct io_rings, sq.tail);
|
|
p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
|
|
p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
|
|
p->sq_off.flags = offsetof(struct io_rings, sq_flags);
|
|
p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
|
|
p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
|
|
|
|
memset(&p->cq_off, 0, sizeof(p->cq_off));
|
|
p->cq_off.head = offsetof(struct io_rings, cq.head);
|
|
p->cq_off.tail = offsetof(struct io_rings, cq.tail);
|
|
p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
|
|
p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
|
|
p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
|
|
p->cq_off.cqes = offsetof(struct io_rings, cqes);
|
|
p->cq_off.flags = offsetof(struct io_rings, cq_flags);
|
|
|
|
p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
|
|
IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
|
|
IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
|
|
IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
|
|
IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
|
|
IORING_FEAT_RSRC_TAGS;
|
|
|
|
if (copy_to_user(params, p, sizeof(*p))) {
|
|
ret = -EFAULT;
|
|
goto err;
|
|
}
|
|
|
|
file = io_uring_get_file(ctx);
|
|
if (IS_ERR(file)) {
|
|
ret = PTR_ERR(file);
|
|
goto err;
|
|
}
|
|
|
|
/*
|
|
* Install ring fd as the very last thing, so we don't risk someone
|
|
* having closed it before we finish setup
|
|
*/
|
|
ret = io_uring_install_fd(ctx, file);
|
|
if (ret < 0) {
|
|
/* fput will clean it up */
|
|
fput(file);
|
|
return ret;
|
|
}
|
|
|
|
trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
|
|
return ret;
|
|
err:
|
|
io_ring_ctx_wait_and_kill(ctx);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Sets up an aio uring context, and returns the fd. Applications asks for a
|
|
* ring size, we return the actual sq/cq ring sizes (among other things) in the
|
|
* params structure passed in.
|
|
*/
|
|
static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
|
|
{
|
|
struct io_uring_params p;
|
|
int i;
|
|
|
|
if (copy_from_user(&p, params, sizeof(p)))
|
|
return -EFAULT;
|
|
for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
|
|
if (p.resv[i])
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
|
|
IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
|
|
IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
|
|
IORING_SETUP_R_DISABLED))
|
|
return -EINVAL;
|
|
|
|
return io_uring_create(entries, &p, params);
|
|
}
|
|
|
|
SYSCALL_DEFINE2(io_uring_setup, u32, entries,
|
|
struct io_uring_params __user *, params)
|
|
{
|
|
return io_uring_setup(entries, params);
|
|
}
|
|
|
|
static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
|
|
{
|
|
struct io_uring_probe *p;
|
|
size_t size;
|
|
int i, ret;
|
|
|
|
size = struct_size(p, ops, nr_args);
|
|
if (size == SIZE_MAX)
|
|
return -EOVERFLOW;
|
|
p = kzalloc(size, GFP_KERNEL);
|
|
if (!p)
|
|
return -ENOMEM;
|
|
|
|
ret = -EFAULT;
|
|
if (copy_from_user(p, arg, size))
|
|
goto out;
|
|
ret = -EINVAL;
|
|
if (memchr_inv(p, 0, size))
|
|
goto out;
|
|
|
|
p->last_op = IORING_OP_LAST - 1;
|
|
if (nr_args > IORING_OP_LAST)
|
|
nr_args = IORING_OP_LAST;
|
|
|
|
for (i = 0; i < nr_args; i++) {
|
|
p->ops[i].op = i;
|
|
if (!io_op_defs[i].not_supported)
|
|
p->ops[i].flags = IO_URING_OP_SUPPORTED;
|
|
}
|
|
p->ops_len = i;
|
|
|
|
ret = 0;
|
|
if (copy_to_user(arg, p, size))
|
|
ret = -EFAULT;
|
|
out:
|
|
kfree(p);
|
|
return ret;
|
|
}
|
|
|
|
static int io_register_personality(struct io_ring_ctx *ctx)
|
|
{
|
|
const struct cred *creds;
|
|
u32 id;
|
|
int ret;
|
|
|
|
creds = get_current_cred();
|
|
|
|
ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
|
|
XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
|
|
if (!ret)
|
|
return id;
|
|
put_cred(creds);
|
|
return ret;
|
|
}
|
|
|
|
static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned int nr_args)
|
|
{
|
|
struct io_uring_restriction *res;
|
|
size_t size;
|
|
int i, ret;
|
|
|
|
/* Restrictions allowed only if rings started disabled */
|
|
if (!(ctx->flags & IORING_SETUP_R_DISABLED))
|
|
return -EBADFD;
|
|
|
|
/* We allow only a single restrictions registration */
|
|
if (ctx->restrictions.registered)
|
|
return -EBUSY;
|
|
|
|
if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
|
|
return -EINVAL;
|
|
|
|
size = array_size(nr_args, sizeof(*res));
|
|
if (size == SIZE_MAX)
|
|
return -EOVERFLOW;
|
|
|
|
res = memdup_user(arg, size);
|
|
if (IS_ERR(res))
|
|
return PTR_ERR(res);
|
|
|
|
ret = 0;
|
|
|
|
for (i = 0; i < nr_args; i++) {
|
|
switch (res[i].opcode) {
|
|
case IORING_RESTRICTION_REGISTER_OP:
|
|
if (res[i].register_op >= IORING_REGISTER_LAST) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
__set_bit(res[i].register_op,
|
|
ctx->restrictions.register_op);
|
|
break;
|
|
case IORING_RESTRICTION_SQE_OP:
|
|
if (res[i].sqe_op >= IORING_OP_LAST) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
__set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
|
|
break;
|
|
case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
|
|
ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
|
|
break;
|
|
case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
|
|
ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
out:
|
|
/* Reset all restrictions if an error happened */
|
|
if (ret != 0)
|
|
memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
|
|
else
|
|
ctx->restrictions.registered = true;
|
|
|
|
kfree(res);
|
|
return ret;
|
|
}
|
|
|
|
static int io_register_enable_rings(struct io_ring_ctx *ctx)
|
|
{
|
|
if (!(ctx->flags & IORING_SETUP_R_DISABLED))
|
|
return -EBADFD;
|
|
|
|
if (ctx->restrictions.registered)
|
|
ctx->restricted = 1;
|
|
|
|
ctx->flags &= ~IORING_SETUP_R_DISABLED;
|
|
if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
|
|
wake_up(&ctx->sq_data->wait);
|
|
return 0;
|
|
}
|
|
|
|
static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
|
|
struct io_uring_rsrc_update2 *up,
|
|
unsigned nr_args)
|
|
{
|
|
__u32 tmp;
|
|
int err;
|
|
|
|
if (up->resv)
|
|
return -EINVAL;
|
|
if (check_add_overflow(up->offset, nr_args, &tmp))
|
|
return -EOVERFLOW;
|
|
err = io_rsrc_node_switch_start(ctx);
|
|
if (err)
|
|
return err;
|
|
|
|
switch (type) {
|
|
case IORING_RSRC_FILE:
|
|
return __io_sqe_files_update(ctx, up, nr_args);
|
|
case IORING_RSRC_BUFFER:
|
|
return __io_sqe_buffers_update(ctx, up, nr_args);
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned nr_args)
|
|
{
|
|
struct io_uring_rsrc_update2 up;
|
|
|
|
if (!nr_args)
|
|
return -EINVAL;
|
|
memset(&up, 0, sizeof(up));
|
|
if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
|
|
return -EFAULT;
|
|
return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
|
|
}
|
|
|
|
static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned size, unsigned type)
|
|
{
|
|
struct io_uring_rsrc_update2 up;
|
|
|
|
if (size != sizeof(up))
|
|
return -EINVAL;
|
|
if (copy_from_user(&up, arg, sizeof(up)))
|
|
return -EFAULT;
|
|
if (!up.nr || up.resv)
|
|
return -EINVAL;
|
|
return __io_register_rsrc_update(ctx, type, &up, up.nr);
|
|
}
|
|
|
|
static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned int size, unsigned int type)
|
|
{
|
|
struct io_uring_rsrc_register rr;
|
|
|
|
/* keep it extendible */
|
|
if (size != sizeof(rr))
|
|
return -EINVAL;
|
|
|
|
memset(&rr, 0, sizeof(rr));
|
|
if (copy_from_user(&rr, arg, size))
|
|
return -EFAULT;
|
|
if (!rr.nr || rr.resv || rr.resv2)
|
|
return -EINVAL;
|
|
|
|
switch (type) {
|
|
case IORING_RSRC_FILE:
|
|
return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
|
|
rr.nr, u64_to_user_ptr(rr.tags));
|
|
case IORING_RSRC_BUFFER:
|
|
return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
|
|
rr.nr, u64_to_user_ptr(rr.tags));
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg,
|
|
unsigned len)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
cpumask_var_t new_mask;
|
|
int ret;
|
|
|
|
if (!tctx || !tctx->io_wq)
|
|
return -EINVAL;
|
|
|
|
if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
|
|
return -ENOMEM;
|
|
|
|
cpumask_clear(new_mask);
|
|
if (len > cpumask_size())
|
|
len = cpumask_size();
|
|
|
|
if (copy_from_user(new_mask, arg, len)) {
|
|
free_cpumask_var(new_mask);
|
|
return -EFAULT;
|
|
}
|
|
|
|
ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
|
|
free_cpumask_var(new_mask);
|
|
return ret;
|
|
}
|
|
|
|
static int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
|
|
{
|
|
struct io_uring_task *tctx = current->io_uring;
|
|
|
|
if (!tctx || !tctx->io_wq)
|
|
return -EINVAL;
|
|
|
|
return io_wq_cpu_affinity(tctx->io_wq, NULL);
|
|
}
|
|
|
|
static bool io_register_op_must_quiesce(int op)
|
|
{
|
|
switch (op) {
|
|
case IORING_REGISTER_BUFFERS:
|
|
case IORING_UNREGISTER_BUFFERS:
|
|
case IORING_REGISTER_FILES:
|
|
case IORING_UNREGISTER_FILES:
|
|
case IORING_REGISTER_FILES_UPDATE:
|
|
case IORING_REGISTER_PROBE:
|
|
case IORING_REGISTER_PERSONALITY:
|
|
case IORING_UNREGISTER_PERSONALITY:
|
|
case IORING_REGISTER_FILES2:
|
|
case IORING_REGISTER_FILES_UPDATE2:
|
|
case IORING_REGISTER_BUFFERS2:
|
|
case IORING_REGISTER_BUFFERS_UPDATE:
|
|
case IORING_REGISTER_IOWQ_AFF:
|
|
case IORING_UNREGISTER_IOWQ_AFF:
|
|
return false;
|
|
default:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
|
|
void __user *arg, unsigned nr_args)
|
|
__releases(ctx->uring_lock)
|
|
__acquires(ctx->uring_lock)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* We're inside the ring mutex, if the ref is already dying, then
|
|
* someone else killed the ctx or is already going through
|
|
* io_uring_register().
|
|
*/
|
|
if (percpu_ref_is_dying(&ctx->refs))
|
|
return -ENXIO;
|
|
|
|
if (ctx->restricted) {
|
|
if (opcode >= IORING_REGISTER_LAST)
|
|
return -EINVAL;
|
|
opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
|
|
if (!test_bit(opcode, ctx->restrictions.register_op))
|
|
return -EACCES;
|
|
}
|
|
|
|
if (io_register_op_must_quiesce(opcode)) {
|
|
percpu_ref_kill(&ctx->refs);
|
|
|
|
/*
|
|
* Drop uring mutex before waiting for references to exit. If
|
|
* another thread is currently inside io_uring_enter() it might
|
|
* need to grab the uring_lock to make progress. If we hold it
|
|
* here across the drain wait, then we can deadlock. It's safe
|
|
* to drop the mutex here, since no new references will come in
|
|
* after we've killed the percpu ref.
|
|
*/
|
|
mutex_unlock(&ctx->uring_lock);
|
|
do {
|
|
ret = wait_for_completion_interruptible(&ctx->ref_comp);
|
|
if (!ret)
|
|
break;
|
|
ret = io_run_task_work_sig();
|
|
if (ret < 0)
|
|
break;
|
|
} while (1);
|
|
mutex_lock(&ctx->uring_lock);
|
|
|
|
if (ret) {
|
|
io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
switch (opcode) {
|
|
case IORING_REGISTER_BUFFERS:
|
|
ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
|
|
break;
|
|
case IORING_UNREGISTER_BUFFERS:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_sqe_buffers_unregister(ctx);
|
|
break;
|
|
case IORING_REGISTER_FILES:
|
|
ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
|
|
break;
|
|
case IORING_UNREGISTER_FILES:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_sqe_files_unregister(ctx);
|
|
break;
|
|
case IORING_REGISTER_FILES_UPDATE:
|
|
ret = io_register_files_update(ctx, arg, nr_args);
|
|
break;
|
|
case IORING_REGISTER_EVENTFD:
|
|
case IORING_REGISTER_EVENTFD_ASYNC:
|
|
ret = -EINVAL;
|
|
if (nr_args != 1)
|
|
break;
|
|
ret = io_eventfd_register(ctx, arg);
|
|
if (ret)
|
|
break;
|
|
if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
|
|
ctx->eventfd_async = 1;
|
|
else
|
|
ctx->eventfd_async = 0;
|
|
break;
|
|
case IORING_UNREGISTER_EVENTFD:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_eventfd_unregister(ctx);
|
|
break;
|
|
case IORING_REGISTER_PROBE:
|
|
ret = -EINVAL;
|
|
if (!arg || nr_args > 256)
|
|
break;
|
|
ret = io_probe(ctx, arg, nr_args);
|
|
break;
|
|
case IORING_REGISTER_PERSONALITY:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_register_personality(ctx);
|
|
break;
|
|
case IORING_UNREGISTER_PERSONALITY:
|
|
ret = -EINVAL;
|
|
if (arg)
|
|
break;
|
|
ret = io_unregister_personality(ctx, nr_args);
|
|
break;
|
|
case IORING_REGISTER_ENABLE_RINGS:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_register_enable_rings(ctx);
|
|
break;
|
|
case IORING_REGISTER_RESTRICTIONS:
|
|
ret = io_register_restrictions(ctx, arg, nr_args);
|
|
break;
|
|
case IORING_REGISTER_FILES2:
|
|
ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
|
|
break;
|
|
case IORING_REGISTER_FILES_UPDATE2:
|
|
ret = io_register_rsrc_update(ctx, arg, nr_args,
|
|
IORING_RSRC_FILE);
|
|
break;
|
|
case IORING_REGISTER_BUFFERS2:
|
|
ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
|
|
break;
|
|
case IORING_REGISTER_BUFFERS_UPDATE:
|
|
ret = io_register_rsrc_update(ctx, arg, nr_args,
|
|
IORING_RSRC_BUFFER);
|
|
break;
|
|
case IORING_REGISTER_IOWQ_AFF:
|
|
ret = -EINVAL;
|
|
if (!arg || !nr_args)
|
|
break;
|
|
ret = io_register_iowq_aff(ctx, arg, nr_args);
|
|
break;
|
|
case IORING_UNREGISTER_IOWQ_AFF:
|
|
ret = -EINVAL;
|
|
if (arg || nr_args)
|
|
break;
|
|
ret = io_unregister_iowq_aff(ctx);
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (io_register_op_must_quiesce(opcode)) {
|
|
/* bring the ctx back to life */
|
|
percpu_ref_reinit(&ctx->refs);
|
|
reinit_completion(&ctx->ref_comp);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
|
|
void __user *, arg, unsigned int, nr_args)
|
|
{
|
|
struct io_ring_ctx *ctx;
|
|
long ret = -EBADF;
|
|
struct fd f;
|
|
|
|
f = fdget(fd);
|
|
if (!f.file)
|
|
return -EBADF;
|
|
|
|
ret = -EOPNOTSUPP;
|
|
if (f.file->f_op != &io_uring_fops)
|
|
goto out_fput;
|
|
|
|
ctx = f.file->private_data;
|
|
|
|
io_run_task_work();
|
|
|
|
mutex_lock(&ctx->uring_lock);
|
|
ret = __io_uring_register(ctx, opcode, arg, nr_args);
|
|
mutex_unlock(&ctx->uring_lock);
|
|
trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
|
|
ctx->cq_ev_fd != NULL, ret);
|
|
out_fput:
|
|
fdput(f);
|
|
return ret;
|
|
}
|
|
|
|
static int __init io_uring_init(void)
|
|
{
|
|
#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
|
|
BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
|
|
BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
|
|
} while (0)
|
|
|
|
#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
|
|
__BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
|
|
BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
|
|
BUILD_BUG_SQE_ELEM(0, __u8, opcode);
|
|
BUILD_BUG_SQE_ELEM(1, __u8, flags);
|
|
BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
|
|
BUILD_BUG_SQE_ELEM(4, __s32, fd);
|
|
BUILD_BUG_SQE_ELEM(8, __u64, off);
|
|
BUILD_BUG_SQE_ELEM(8, __u64, addr2);
|
|
BUILD_BUG_SQE_ELEM(16, __u64, addr);
|
|
BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
|
|
BUILD_BUG_SQE_ELEM(24, __u32, len);
|
|
BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
|
|
BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
|
|
BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
|
|
BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
|
|
BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
|
|
BUILD_BUG_SQE_ELEM(32, __u64, user_data);
|
|
BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
|
|
BUILD_BUG_SQE_ELEM(40, __u16, buf_group);
|
|
BUILD_BUG_SQE_ELEM(42, __u16, personality);
|
|
BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
|
|
|
|
BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
|
|
sizeof(struct io_uring_rsrc_update));
|
|
BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
|
|
sizeof(struct io_uring_rsrc_update2));
|
|
/* should fit into one byte */
|
|
BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
|
|
BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
|
|
|
|
req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
|
|
SLAB_ACCOUNT);
|
|
return 0;
|
|
};
|
|
__initcall(io_uring_init);
|