OpenCloudOS-Kernel/fs/xfs/xfs_inode.h

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_INODE_H__
#define __XFS_INODE_H__
#include "xfs_inode_buf.h"
#include "xfs_inode_fork.h"
/*
* Kernel only inode definitions
*/
struct xfs_dinode;
struct xfs_inode;
struct xfs_buf;
struct xfs_bmbt_irec;
struct xfs_inode_log_item;
struct xfs_mount;
struct xfs_trans;
struct xfs_dquot;
typedef struct xfs_inode {
/* Inode linking and identification information. */
struct xfs_mount *i_mount; /* fs mount struct ptr */
struct xfs_dquot *i_udquot; /* user dquot */
struct xfs_dquot *i_gdquot; /* group dquot */
struct xfs_dquot *i_pdquot; /* project dquot */
/* Inode location stuff */
xfs_ino_t i_ino; /* inode number (agno/agino)*/
struct xfs_imap i_imap; /* location for xfs_imap() */
/* Extent information. */
struct xfs_ifork *i_afp; /* attribute fork pointer */
struct xfs_ifork *i_cowfp; /* copy on write extents */
struct xfs_ifork i_df; /* data fork */
xfs: abstract the differences in dir2/dir3 via an ops vector Lots of the dir code now goes through switches to determine what is the correct on-disk format to parse. It generally involves a "xfs_sbversion_hasfoo" check, deferencing the superblock version and feature fields and hence touching several cache lines per operation in the process. Some operations do multiple checks because they nest conditional operations and they don't pass the information in a direct fashion between each other. Hence, add an ops vector to the xfs_inode structure that is configured when the inode is initialised to point to all the correct decode and encoding operations. This will significantly reduce the branchiness and cacheline footprint of the directory object decoding and encoding. This is the first patch in a series of conversion patches. It will introduce the ops structure, the setup of it and add the first operation to the vector. Subsequent patches will convert directory ops one at a time to keep the changes simple and obvious. Just this patch shows the benefit of such an approach on code size. Just converting the two shortform dir operations as this patch does decreases the built binary size by ~1500 bytes: $ size fs/xfs/xfs.o.orig fs/xfs/xfs.o.p1 text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 $ That's a significant decrease in the instruction cache footprint of the directory code for such a simple change, and indicates that this approach is definitely worth pursuing further. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-29 19:11:46 +08:00
/* operations vectors */
const struct xfs_dir_ops *d_ops; /* directory ops vector */
/* Transaction and locking information. */
struct xfs_inode_log_item *i_itemp; /* logging information */
mrlock_t i_lock; /* inode lock */
mrlock_t i_mmaplock; /* inode mmap IO lock */
atomic_t i_pincount; /* inode pin count */
/*
* Bitsets of inode metadata that have been checked and/or are sick.
* Callers must hold i_flags_lock before accessing this field.
*/
uint16_t i_checked;
uint16_t i_sick;
spinlock_t i_flags_lock; /* inode i_flags lock */
/* Miscellaneous state. */
unsigned long i_flags; /* see defined flags below */
uint64_t i_delayed_blks; /* count of delay alloc blks */
struct xfs_icdinode i_d; /* most of ondisk inode */
xfs_extnum_t i_cnextents; /* # of extents in cow fork */
unsigned int i_cformat; /* format of cow fork */
/* VFS inode */
struct inode i_vnode; /* embedded VFS inode */
xfs: implement per-inode writeback completion queues When scheduling writeback of dirty file data in the page cache, XFS uses IO completion workqueue items to ensure that filesystem metadata only updates after the write completes successfully. This is essential for converting unwritten extents to real extents at the right time and performing COW remappings. Unfortunately, XFS queues each IO completion work item to an unbounded workqueue, which means that the kernel can spawn dozens of threads to try to handle the items quickly. These threads need to take the ILOCK to update file metadata, which results in heavy ILOCK contention if a large number of the work items target a single file, which is inefficient. Worse yet, the writeback completion threads get stuck waiting for the ILOCK while holding transaction reservations, which can use up all available log reservation space. When that happens, metadata updates to other parts of the filesystem grind to a halt, even if the filesystem could otherwise have handled it. Even worse, if one of the things grinding to a halt happens to be a thread in the middle of a defer-ops finish holding the same ILOCK and trying to obtain more log reservation having exhausted the permanent reservation, we now have an ABBA deadlock - writeback completion has a transaction reserved and wants the ILOCK, and someone else has the ILOCK and wants a transaction reservation. Therefore, we create a per-inode writeback io completion queue + work item. When writeback finishes, it can add the ioend to the per-inode queue and let the single worker item process that queue. This dramatically cuts down on the number of kworkers and ILOCK contention in the system, and seems to have eliminated an occasional deadlock I was seeing while running generic/476. Testing with a program that simulates a heavy random-write workload to a single file demonstrates that the number of kworkers drops from approximately 120 threads per file to 1, without dramatically changing write bandwidth or pagecache access latency. Note that we leave the xfs-conv workqueue's max_active alone because we still want to be able to run ioend processing for as many inodes as the system can handle. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-16 04:13:20 +08:00
/* pending io completions */
spinlock_t i_ioend_lock;
struct work_struct i_ioend_work;
struct list_head i_ioend_list;
} xfs_inode_t;
/* Convert from vfs inode to xfs inode */
static inline struct xfs_inode *XFS_I(struct inode *inode)
{
return container_of(inode, struct xfs_inode, i_vnode);
}
/* convert from xfs inode to vfs inode */
static inline struct inode *VFS_I(struct xfs_inode *ip)
{
return &ip->i_vnode;
}
/*
* For regular files we only update the on-disk filesize when actually
* writing data back to disk. Until then only the copy in the VFS inode
* is uptodate.
*/
static inline xfs_fsize_t XFS_ISIZE(struct xfs_inode *ip)
{
if (S_ISREG(VFS_I(ip)->i_mode))
return i_size_read(VFS_I(ip));
return ip->i_d.di_size;
}
/*
* If this I/O goes past the on-disk inode size update it unless it would
* be past the current in-core inode size.
*/
static inline xfs_fsize_t
xfs_new_eof(struct xfs_inode *ip, xfs_fsize_t new_size)
{
xfs_fsize_t i_size = i_size_read(VFS_I(ip));
2014-10-02 07:21:53 +08:00
if (new_size > i_size || new_size < 0)
new_size = i_size;
return new_size > ip->i_d.di_size ? new_size : 0;
}
/*
* i_flags helper functions
*/
static inline void
__xfs_iflags_set(xfs_inode_t *ip, unsigned short flags)
{
ip->i_flags |= flags;
}
static inline void
xfs_iflags_set(xfs_inode_t *ip, unsigned short flags)
{
spin_lock(&ip->i_flags_lock);
__xfs_iflags_set(ip, flags);
spin_unlock(&ip->i_flags_lock);
}
static inline void
xfs_iflags_clear(xfs_inode_t *ip, unsigned short flags)
{
spin_lock(&ip->i_flags_lock);
ip->i_flags &= ~flags;
spin_unlock(&ip->i_flags_lock);
}
static inline int
__xfs_iflags_test(xfs_inode_t *ip, unsigned short flags)
{
return (ip->i_flags & flags);
}
static inline int
xfs_iflags_test(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = __xfs_iflags_test(ip, flags);
spin_unlock(&ip->i_flags_lock);
return ret;
}
static inline int
xfs_iflags_test_and_clear(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = ip->i_flags & flags;
if (ret)
ip->i_flags &= ~flags;
spin_unlock(&ip->i_flags_lock);
return ret;
}
static inline int
xfs_iflags_test_and_set(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = ip->i_flags & flags;
if (!ret)
ip->i_flags |= flags;
spin_unlock(&ip->i_flags_lock);
return ret;
}
/*
* Project quota id helpers (previously projid was 16bit only
* and using two 16bit values to hold new 32bit projid was chosen
* to retain compatibility with "old" filesystems).
*/
static inline prid_t
xfs_get_projid(struct xfs_inode *ip)
{
return (prid_t)ip->i_d.di_projid_hi << 16 | ip->i_d.di_projid_lo;
}
static inline void
xfs_set_projid(struct xfs_inode *ip,
prid_t projid)
{
ip->i_d.di_projid_hi = (uint16_t) (projid >> 16);
ip->i_d.di_projid_lo = (uint16_t) (projid & 0xffff);
}
static inline prid_t
xfs_get_initial_prid(struct xfs_inode *dp)
{
if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
return xfs_get_projid(dp);
return XFS_PROJID_DEFAULT;
}
static inline bool xfs_is_reflink_inode(struct xfs_inode *ip)
{
return ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
}
/*
* Check if an inode has any data in the COW fork. This might be often false
* even for inodes with the reflink flag when there is no pending COW operation.
*/
static inline bool xfs_inode_has_cow_data(struct xfs_inode *ip)
{
return ip->i_cowfp && ip->i_cowfp->if_bytes;
}
/*
* In-core inode flags.
*/
#define XFS_IRECLAIM (1 << 0) /* started reclaiming this inode */
#define XFS_ISTALE (1 << 1) /* inode has been staled */
#define XFS_IRECLAIMABLE (1 << 2) /* inode can be reclaimed */
#define __XFS_INEW_BIT 3 /* inode has just been allocated */
#define XFS_INEW (1 << __XFS_INEW_BIT)
#define XFS_ITRUNCATED (1 << 5) /* truncated down so flush-on-close */
#define XFS_IDIRTY_RELEASE (1 << 6) /* dirty release already seen */
#define __XFS_IFLOCK_BIT 7 /* inode is being flushed right now */
#define XFS_IFLOCK (1 << __XFS_IFLOCK_BIT)
#define __XFS_IPINNED_BIT 8 /* wakeup key for zero pin count */
#define XFS_IPINNED (1 << __XFS_IPINNED_BIT)
#define XFS_IDONTCACHE (1 << 9) /* don't cache the inode long term */
#define XFS_IEOFBLOCKS (1 << 10)/* has the preallocblocks tag set */
/*
* If this unlinked inode is in the middle of recovery, don't let drop_inode
* truncate and free the inode. This can happen if we iget the inode during
* log recovery to replay a bmap operation on the inode.
*/
#define XFS_IRECOVERY (1 << 11)
#define XFS_ICOWBLOCKS (1 << 12)/* has the cowblocks tag set */
/*
* Per-lifetime flags need to be reset when re-using a reclaimable inode during
* inode lookup. This prevents unintended behaviour on the new inode from
* ocurring.
*/
#define XFS_IRECLAIM_RESET_FLAGS \
(XFS_IRECLAIMABLE | XFS_IRECLAIM | \
XFS_IDIRTY_RELEASE | XFS_ITRUNCATED)
/*
* Synchronize processes attempting to flush the in-core inode back to disk.
*/
static inline int xfs_isiflocked(struct xfs_inode *ip)
{
return xfs_iflags_test(ip, XFS_IFLOCK);
}
extern void __xfs_iflock(struct xfs_inode *ip);
static inline int xfs_iflock_nowait(struct xfs_inode *ip)
{
return !xfs_iflags_test_and_set(ip, XFS_IFLOCK);
}
static inline void xfs_iflock(struct xfs_inode *ip)
{
if (!xfs_iflock_nowait(ip))
__xfs_iflock(ip);
}
static inline void xfs_ifunlock(struct xfs_inode *ip)
{
ASSERT(xfs_isiflocked(ip));
xfs_iflags_clear(ip, XFS_IFLOCK);
smp_mb();
wake_up_bit(&ip->i_flags, __XFS_IFLOCK_BIT);
}
/*
* Flags for inode locking.
* Bit ranges: 1<<1 - 1<<16-1 -- iolock/ilock modes (bitfield)
* 1<<16 - 1<<32-1 -- lockdep annotation (integers)
*/
#define XFS_IOLOCK_EXCL (1<<0)
#define XFS_IOLOCK_SHARED (1<<1)
#define XFS_ILOCK_EXCL (1<<2)
#define XFS_ILOCK_SHARED (1<<3)
#define XFS_MMAPLOCK_EXCL (1<<4)
#define XFS_MMAPLOCK_SHARED (1<<5)
#define XFS_LOCK_MASK (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED \
| XFS_ILOCK_EXCL | XFS_ILOCK_SHARED \
| XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED)
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
#define XFS_LOCK_FLAGS \
{ XFS_IOLOCK_EXCL, "IOLOCK_EXCL" }, \
{ XFS_IOLOCK_SHARED, "IOLOCK_SHARED" }, \
{ XFS_ILOCK_EXCL, "ILOCK_EXCL" }, \
{ XFS_ILOCK_SHARED, "ILOCK_SHARED" }, \
{ XFS_MMAPLOCK_EXCL, "MMAPLOCK_EXCL" }, \
{ XFS_MMAPLOCK_SHARED, "MMAPLOCK_SHARED" }
xfs: event tracing support Convert the old xfs tracing support that could only be used with the out of tree kdb and xfsidbg patches to use the generic event tracer. To use it make sure CONFIG_EVENT_TRACING is enabled and then enable all xfs trace channels by: echo 1 > /sys/kernel/debug/tracing/events/xfs/enable or alternatively enable single events by just doing the same in one event subdirectory, e.g. echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable or set more complex filters, etc. In Documentation/trace/events.txt all this is desctribed in more detail. To reads the events do a cat /sys/kernel/debug/tracing/trace Compared to the last posting this patch converts the tracing mostly to the one tracepoint per callsite model that other users of the new tracing facility also employ. This allows a very fine-grained control of the tracing, a cleaner output of the traces and also enables the perf tool to use each tracepoint as a virtual performance counter, allowing us to e.g. count how often certain workloads git various spots in XFS. Take a look at http://lwn.net/Articles/346470/ for some examples. Also the btree tracing isn't included at all yet, as it will require additional core tracing features not in mainline yet, I plan to deliver it later. And the really nice thing about this patch is that it actually removes many lines of code while adding this nice functionality: fs/xfs/Makefile | 8 fs/xfs/linux-2.6/xfs_acl.c | 1 fs/xfs/linux-2.6/xfs_aops.c | 52 - fs/xfs/linux-2.6/xfs_aops.h | 2 fs/xfs/linux-2.6/xfs_buf.c | 117 +-- fs/xfs/linux-2.6/xfs_buf.h | 33 fs/xfs/linux-2.6/xfs_fs_subr.c | 3 fs/xfs/linux-2.6/xfs_ioctl.c | 1 fs/xfs/linux-2.6/xfs_ioctl32.c | 1 fs/xfs/linux-2.6/xfs_iops.c | 1 fs/xfs/linux-2.6/xfs_linux.h | 1 fs/xfs/linux-2.6/xfs_lrw.c | 87 -- fs/xfs/linux-2.6/xfs_lrw.h | 45 - fs/xfs/linux-2.6/xfs_super.c | 104 --- fs/xfs/linux-2.6/xfs_super.h | 7 fs/xfs/linux-2.6/xfs_sync.c | 1 fs/xfs/linux-2.6/xfs_trace.c | 75 ++ fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++ fs/xfs/linux-2.6/xfs_vnode.h | 4 fs/xfs/quota/xfs_dquot.c | 110 --- fs/xfs/quota/xfs_dquot.h | 21 fs/xfs/quota/xfs_qm.c | 40 - fs/xfs/quota/xfs_qm_syscalls.c | 4 fs/xfs/support/ktrace.c | 323 --------- fs/xfs/support/ktrace.h | 85 -- fs/xfs/xfs.h | 16 fs/xfs/xfs_ag.h | 14 fs/xfs/xfs_alloc.c | 230 +----- fs/xfs/xfs_alloc.h | 27 fs/xfs/xfs_alloc_btree.c | 1 fs/xfs/xfs_attr.c | 107 --- fs/xfs/xfs_attr.h | 10 fs/xfs/xfs_attr_leaf.c | 14 fs/xfs/xfs_attr_sf.h | 40 - fs/xfs/xfs_bmap.c | 507 +++------------ fs/xfs/xfs_bmap.h | 49 - fs/xfs/xfs_bmap_btree.c | 6 fs/xfs/xfs_btree.c | 5 fs/xfs/xfs_btree_trace.h | 17 fs/xfs/xfs_buf_item.c | 87 -- fs/xfs/xfs_buf_item.h | 20 fs/xfs/xfs_da_btree.c | 3 fs/xfs/xfs_da_btree.h | 7 fs/xfs/xfs_dfrag.c | 2 fs/xfs/xfs_dir2.c | 8 fs/xfs/xfs_dir2_block.c | 20 fs/xfs/xfs_dir2_leaf.c | 21 fs/xfs/xfs_dir2_node.c | 27 fs/xfs/xfs_dir2_sf.c | 26 fs/xfs/xfs_dir2_trace.c | 216 ------ fs/xfs/xfs_dir2_trace.h | 72 -- fs/xfs/xfs_filestream.c | 8 fs/xfs/xfs_fsops.c | 2 fs/xfs/xfs_iget.c | 111 --- fs/xfs/xfs_inode.c | 67 -- fs/xfs/xfs_inode.h | 76 -- fs/xfs/xfs_inode_item.c | 5 fs/xfs/xfs_iomap.c | 85 -- fs/xfs/xfs_iomap.h | 8 fs/xfs/xfs_log.c | 181 +---- fs/xfs/xfs_log_priv.h | 20 fs/xfs/xfs_log_recover.c | 1 fs/xfs/xfs_mount.c | 2 fs/xfs/xfs_quota.h | 8 fs/xfs/xfs_rename.c | 1 fs/xfs/xfs_rtalloc.c | 1 fs/xfs/xfs_rw.c | 3 fs/xfs/xfs_trans.h | 47 + fs/xfs/xfs_trans_buf.c | 62 - fs/xfs/xfs_vnodeops.c | 8 70 files changed, 2151 insertions(+), 2592 deletions(-) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-15 07:14:59 +08:00
/*
* Flags for lockdep annotations.
*
* XFS_LOCK_PARENT - for directory operations that require locking a
xfs: clean up inode lockdep annotations Lockdep annotations are a maintenance nightmare. Locking has to be modified to suit the limitations of the annotations, and we're always having to fix the annotations because they are unable to express the complexity of locking heirarchies correctly. So, next up, we've got more issues with lockdep annotations for inode locking w.r.t. XFS_LOCK_PARENT: - lockdep classes are exclusive and can't be ORed together to form new classes. - IOLOCK needs multiple PARENT subclasses to express the changes needed for the readdir locking rework needed to stop the endless flow of lockdep false positives involving readdir calling filldir under the ILOCK. - there are only 8 unique lockdep subclasses available, so we can't create a generic solution. IOWs we need to treat the 3-bit space available to each lock type differently: - IOLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 IOLOCK subclasses - at least 2 IOLOCK_PARENT subclasses - MMAPLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 MMAPLOCK subclasses - ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs: - at least 5 ILOCK subclasses - one ILOCK_PARENT subclass - one RTBITMAP subclass - one RTSUM subclass For the IOLOCK, split the space into two sets of subclasses. For the MMAPLOCK, just use half the space for the one subclass to match the non-parent lock classes of the IOLOCK. For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the remaining individual subclasses. Because they are now all different, modify xfs_lock_inumorder() to handle the nested subclasses, and to assert fail if passed an invalid subclass. Further, annotate xfs_lock_inodes() to assert fail if an invalid combination of lock primitives and inode counts are passed that would result in a lockdep subclass annotation overflow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 08:32:49 +08:00
* parent directory inode and a child entry inode. IOLOCK requires nesting,
* MMAPLOCK does not support this class, ILOCK requires a single subclass
* to differentiate parent from child.
*
* XFS_LOCK_RTBITMAP/XFS_LOCK_RTSUM - the realtime device bitmap and summary
* inodes do not participate in the normal lock order, and thus have their
* own subclasses.
*
* XFS_LOCK_INUMORDER - for locking several inodes at the some time
* with xfs_lock_inodes(). This flag is used as the starting subclass
* and each subsequent lock acquired will increment the subclass by one.
xfs: clean up inode lockdep annotations Lockdep annotations are a maintenance nightmare. Locking has to be modified to suit the limitations of the annotations, and we're always having to fix the annotations because they are unable to express the complexity of locking heirarchies correctly. So, next up, we've got more issues with lockdep annotations for inode locking w.r.t. XFS_LOCK_PARENT: - lockdep classes are exclusive and can't be ORed together to form new classes. - IOLOCK needs multiple PARENT subclasses to express the changes needed for the readdir locking rework needed to stop the endless flow of lockdep false positives involving readdir calling filldir under the ILOCK. - there are only 8 unique lockdep subclasses available, so we can't create a generic solution. IOWs we need to treat the 3-bit space available to each lock type differently: - IOLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 IOLOCK subclasses - at least 2 IOLOCK_PARENT subclasses - MMAPLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 MMAPLOCK subclasses - ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs: - at least 5 ILOCK subclasses - one ILOCK_PARENT subclass - one RTBITMAP subclass - one RTSUM subclass For the IOLOCK, split the space into two sets of subclasses. For the MMAPLOCK, just use half the space for the one subclass to match the non-parent lock classes of the IOLOCK. For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the remaining individual subclasses. Because they are now all different, modify xfs_lock_inumorder() to handle the nested subclasses, and to assert fail if passed an invalid subclass. Further, annotate xfs_lock_inodes() to assert fail if an invalid combination of lock primitives and inode counts are passed that would result in a lockdep subclass annotation overflow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 08:32:49 +08:00
* However, MAX_LOCKDEP_SUBCLASSES == 8, which means we are greatly
* limited to the subclasses we can represent via nesting. We need at least
* 5 inodes nest depth for the ILOCK through rename, and we also have to support
* XFS_ILOCK_PARENT, which gives 6 subclasses. Then we have XFS_ILOCK_RTBITMAP
* and XFS_ILOCK_RTSUM, which are another 2 unique subclasses, so that's all
* 8 subclasses supported by lockdep.
*
* This also means we have to number the sub-classes in the lowest bits of
* the mask we keep, and we have to ensure we never exceed 3 bits of lockdep
* mask and we can't use bit-masking to build the subclasses. What a mess.
*
* Bit layout:
*
* Bit Lock Region
* 16-19 XFS_IOLOCK_SHIFT dependencies
* 20-23 XFS_MMAPLOCK_SHIFT dependencies
* 24-31 XFS_ILOCK_SHIFT dependencies
*
* IOLOCK values
*
* 0-3 subclass value
* 4-7 unused
xfs: clean up inode lockdep annotations Lockdep annotations are a maintenance nightmare. Locking has to be modified to suit the limitations of the annotations, and we're always having to fix the annotations because they are unable to express the complexity of locking heirarchies correctly. So, next up, we've got more issues with lockdep annotations for inode locking w.r.t. XFS_LOCK_PARENT: - lockdep classes are exclusive and can't be ORed together to form new classes. - IOLOCK needs multiple PARENT subclasses to express the changes needed for the readdir locking rework needed to stop the endless flow of lockdep false positives involving readdir calling filldir under the ILOCK. - there are only 8 unique lockdep subclasses available, so we can't create a generic solution. IOWs we need to treat the 3-bit space available to each lock type differently: - IOLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 IOLOCK subclasses - at least 2 IOLOCK_PARENT subclasses - MMAPLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 MMAPLOCK subclasses - ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs: - at least 5 ILOCK subclasses - one ILOCK_PARENT subclass - one RTBITMAP subclass - one RTSUM subclass For the IOLOCK, split the space into two sets of subclasses. For the MMAPLOCK, just use half the space for the one subclass to match the non-parent lock classes of the IOLOCK. For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the remaining individual subclasses. Because they are now all different, modify xfs_lock_inumorder() to handle the nested subclasses, and to assert fail if passed an invalid subclass. Further, annotate xfs_lock_inodes() to assert fail if an invalid combination of lock primitives and inode counts are passed that would result in a lockdep subclass annotation overflow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 08:32:49 +08:00
*
* MMAPLOCK values
*
* 0-3 subclass value
* 4-7 unused
*
* ILOCK values
* 0-4 subclass values
* 5 PARENT subclass (not nestable)
* 6 RTBITMAP subclass (not nestable)
* 7 RTSUM subclass (not nestable)
*
*/
xfs: clean up inode lockdep annotations Lockdep annotations are a maintenance nightmare. Locking has to be modified to suit the limitations of the annotations, and we're always having to fix the annotations because they are unable to express the complexity of locking heirarchies correctly. So, next up, we've got more issues with lockdep annotations for inode locking w.r.t. XFS_LOCK_PARENT: - lockdep classes are exclusive and can't be ORed together to form new classes. - IOLOCK needs multiple PARENT subclasses to express the changes needed for the readdir locking rework needed to stop the endless flow of lockdep false positives involving readdir calling filldir under the ILOCK. - there are only 8 unique lockdep subclasses available, so we can't create a generic solution. IOWs we need to treat the 3-bit space available to each lock type differently: - IOLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 IOLOCK subclasses - at least 2 IOLOCK_PARENT subclasses - MMAPLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 MMAPLOCK subclasses - ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs: - at least 5 ILOCK subclasses - one ILOCK_PARENT subclass - one RTBITMAP subclass - one RTSUM subclass For the IOLOCK, split the space into two sets of subclasses. For the MMAPLOCK, just use half the space for the one subclass to match the non-parent lock classes of the IOLOCK. For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the remaining individual subclasses. Because they are now all different, modify xfs_lock_inumorder() to handle the nested subclasses, and to assert fail if passed an invalid subclass. Further, annotate xfs_lock_inodes() to assert fail if an invalid combination of lock primitives and inode counts are passed that would result in a lockdep subclass annotation overflow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 08:32:49 +08:00
#define XFS_IOLOCK_SHIFT 16
#define XFS_IOLOCK_MAX_SUBCLASS 3
xfs: clean up inode lockdep annotations Lockdep annotations are a maintenance nightmare. Locking has to be modified to suit the limitations of the annotations, and we're always having to fix the annotations because they are unable to express the complexity of locking heirarchies correctly. So, next up, we've got more issues with lockdep annotations for inode locking w.r.t. XFS_LOCK_PARENT: - lockdep classes are exclusive and can't be ORed together to form new classes. - IOLOCK needs multiple PARENT subclasses to express the changes needed for the readdir locking rework needed to stop the endless flow of lockdep false positives involving readdir calling filldir under the ILOCK. - there are only 8 unique lockdep subclasses available, so we can't create a generic solution. IOWs we need to treat the 3-bit space available to each lock type differently: - IOLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 IOLOCK subclasses - at least 2 IOLOCK_PARENT subclasses - MMAPLOCK uses xfs_lock_two_inodes(), so needs: - at least 2 MMAPLOCK subclasses - ILOCK uses xfs_lock_inodes with up to 5 inodes, so needs: - at least 5 ILOCK subclasses - one ILOCK_PARENT subclass - one RTBITMAP subclass - one RTSUM subclass For the IOLOCK, split the space into two sets of subclasses. For the MMAPLOCK, just use half the space for the one subclass to match the non-parent lock classes of the IOLOCK. For the ILOCK, use 0-4 as the ILOCK subclasses, 5-7 for the remaining individual subclasses. Because they are now all different, modify xfs_lock_inumorder() to handle the nested subclasses, and to assert fail if passed an invalid subclass. Further, annotate xfs_lock_inodes() to assert fail if an invalid combination of lock primitives and inode counts are passed that would result in a lockdep subclass annotation overflow. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 08:32:49 +08:00
#define XFS_IOLOCK_DEP_MASK 0x000f0000
#define XFS_MMAPLOCK_SHIFT 20
#define XFS_MMAPLOCK_NUMORDER 0
#define XFS_MMAPLOCK_MAX_SUBCLASS 3
#define XFS_MMAPLOCK_DEP_MASK 0x00f00000
#define XFS_ILOCK_SHIFT 24
#define XFS_ILOCK_PARENT_VAL 5
#define XFS_ILOCK_MAX_SUBCLASS (XFS_ILOCK_PARENT_VAL - 1)
#define XFS_ILOCK_RTBITMAP_VAL 6
#define XFS_ILOCK_RTSUM_VAL 7
#define XFS_ILOCK_DEP_MASK 0xff000000
#define XFS_ILOCK_PARENT (XFS_ILOCK_PARENT_VAL << XFS_ILOCK_SHIFT)
#define XFS_ILOCK_RTBITMAP (XFS_ILOCK_RTBITMAP_VAL << XFS_ILOCK_SHIFT)
#define XFS_ILOCK_RTSUM (XFS_ILOCK_RTSUM_VAL << XFS_ILOCK_SHIFT)
#define XFS_LOCK_SUBCLASS_MASK (XFS_IOLOCK_DEP_MASK | \
XFS_MMAPLOCK_DEP_MASK | \
XFS_ILOCK_DEP_MASK)
#define XFS_IOLOCK_DEP(flags) (((flags) & XFS_IOLOCK_DEP_MASK) \
>> XFS_IOLOCK_SHIFT)
#define XFS_MMAPLOCK_DEP(flags) (((flags) & XFS_MMAPLOCK_DEP_MASK) \
>> XFS_MMAPLOCK_SHIFT)
#define XFS_ILOCK_DEP(flags) (((flags) & XFS_ILOCK_DEP_MASK) \
>> XFS_ILOCK_SHIFT)
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-21 05:42:38 +08:00
/*
* Layouts are broken in the BREAK_WRITE case to ensure that
* layout-holders do not collide with local writes. Additionally,
* layouts are broken in the BREAK_UNMAP case to make sure the
* layout-holder has a consistent view of the file's extent map. While
* BREAK_WRITE breaks can be satisfied by recalling FL_LAYOUT leases,
* BREAK_UNMAP breaks additionally require waiting for busy dax-pages to
* go idle.
*/
enum layout_break_reason {
BREAK_WRITE,
BREAK_UNMAP,
};
/*
* For multiple groups support: if S_ISGID bit is set in the parent
* directory, group of new file is set to that of the parent, and
* new subdirectory gets S_ISGID bit from parent.
*/
#define XFS_INHERIT_GID(pip) \
(((pip)->i_mount->m_flags & XFS_MOUNT_GRPID) || \
(VFS_I(pip)->i_mode & S_ISGID))
int xfs_release(struct xfs_inode *ip);
void xfs_inactive(struct xfs_inode *ip);
int xfs_lookup(struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode **ipp, struct xfs_name *ci_name);
int xfs_create(struct xfs_inode *dp, struct xfs_name *name,
umode_t mode, dev_t rdev, struct xfs_inode **ipp);
int xfs_create_tmpfile(struct xfs_inode *dp, umode_t mode,
struct xfs_inode **ipp);
int xfs_remove(struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode *ip);
int xfs_link(struct xfs_inode *tdp, struct xfs_inode *sip,
struct xfs_name *target_name);
int xfs_rename(struct xfs_inode *src_dp, struct xfs_name *src_name,
struct xfs_inode *src_ip, struct xfs_inode *target_dp,
struct xfs_name *target_name,
struct xfs_inode *target_ip, unsigned int flags);
void xfs_ilock(xfs_inode_t *, uint);
int xfs_ilock_nowait(xfs_inode_t *, uint);
void xfs_iunlock(xfs_inode_t *, uint);
void xfs_ilock_demote(xfs_inode_t *, uint);
int xfs_isilocked(xfs_inode_t *, uint);
uint xfs_ilock_data_map_shared(struct xfs_inode *);
uint xfs_ilock_attr_map_shared(struct xfs_inode *);
uint xfs_ip2xflags(struct xfs_inode *);
int xfs_ifree(struct xfs_trans *, struct xfs_inode *);
int xfs_itruncate_extents_flags(struct xfs_trans **,
struct xfs_inode *, int, xfs_fsize_t, int);
void xfs_iext_realloc(xfs_inode_t *, int, int);
void xfs_iunpin_wait(xfs_inode_t *);
#define xfs_ipincount(ip) ((unsigned int) atomic_read(&ip->i_pincount))
int xfs_iflush(struct xfs_inode *, struct xfs_buf **);
void xfs_lock_two_inodes(struct xfs_inode *ip0, uint ip0_mode,
struct xfs_inode *ip1, uint ip1_mode);
xfs_extlen_t xfs_get_extsz_hint(struct xfs_inode *ip);
xfs_extlen_t xfs_get_cowextsz_hint(struct xfs_inode *ip);
int xfs_dir_ialloc(struct xfs_trans **, struct xfs_inode *, umode_t,
xfs: remove "no-allocation" reservations for file creations If we create a new file we will need an inode, and usually some metadata in the parent direction. Aiming for everything to go well despite the lack of a reservation leads to dirty transactions cancelled under a heavy create/delete load. This patch removes those nospace transactions, which will lead to slightly earlier ENOSPC on some workloads, but instead prevent file system shutdowns due to cancelling dirty transactions for others. A customer could observe assertations failures and shutdowns due to cancelation of dirty transactions during heavy NFS workloads as shown below: 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728125] XFS: Assertion failed: error != -ENOSPC, file: fs/xfs/xfs_inode.c, line: 1262 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728222] Call Trace: 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728246] [<ffffffff81795daf>] dump_stack+0x63/0x81 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728262] [<ffffffff810a1a5a>] warn_slowpath_common+0x8a/0xc0 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728264] [<ffffffff810a1b8a>] warn_slowpath_null+0x1a/0x20 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728285] [<ffffffffa01bf403>] asswarn+0x33/0x40 [xfs] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728308] [<ffffffffa01bb07e>] xfs_create+0x7be/0x7d0 [xfs] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728329] [<ffffffffa01b6ffb>] xfs_generic_create+0x1fb/0x2e0 [xfs] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728348] [<ffffffffa01b7114>] xfs_vn_mknod+0x14/0x20 [xfs] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728366] [<ffffffffa01b7153>] xfs_vn_create+0x13/0x20 [xfs] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728380] [<ffffffff81231de5>] vfs_create+0xd5/0x140 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728390] [<ffffffffa045ddb9>] do_nfsd_create+0x499/0x610 [nfsd] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728396] [<ffffffffa0465fa5>] nfsd3_proc_create+0x135/0x210 [nfsd] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728401] [<ffffffffa04561e3>] nfsd_dispatch+0xc3/0x210 [nfsd] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728416] [<ffffffffa03bfa43>] svc_process_common+0x453/0x6f0 [sunrpc] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728423] [<ffffffffa03bfdf3>] svc_process+0x113/0x1f0 [sunrpc] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728427] [<ffffffffa0455bcf>] nfsd+0x10f/0x180 [nfsd] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728432] [<ffffffffa0455ac0>] ? nfsd_destroy+0x80/0x80 [nfsd] 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728438] [<ffffffff810c0d58>] kthread+0xd8/0xf0 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728441] [<ffffffff810c0c80>] ? kthread_create_on_node+0x1b0/0x1b0 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728451] [<ffffffff8179d962>] ret_from_fork+0x42/0x70 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728453] [<ffffffff810c0c80>] ? kthread_create_on_node+0x1b0/0x1b0 2017-05-30 21:17:06 kernel: WARNING: [ 2670.728454] ---[ end trace f9822c842fec81d4 ]--- 2017-05-30 21:17:06 kernel: ALERT: [ 2670.728477] XFS (sdb): Internal error xfs_trans_cancel at line 983 of file fs/xfs/xfs_trans.c. Caller xfs_create+0x4ee/0x7d0 [xfs] 2017-05-30 21:17:06 kernel: ALERT: [ 2670.728684] XFS (sdb): Corruption of in-memory data detected. Shutting down filesystem 2017-05-30 21:17:06 kernel: ALERT: [ 2670.728685] XFS (sdb): Please umount the filesystem and rectify the problem(s) Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-12-05 09:32:55 +08:00
xfs_nlink_t, dev_t, prid_t,
struct xfs_inode **);
static inline int
xfs_itruncate_extents(
struct xfs_trans **tpp,
struct xfs_inode *ip,
int whichfork,
xfs_fsize_t new_size)
{
return xfs_itruncate_extents_flags(tpp, ip, whichfork, new_size, 0);
}
/* from xfs_file.c */
enum xfs_prealloc_flags {
XFS_PREALLOC_SET = (1 << 1),
XFS_PREALLOC_CLEAR = (1 << 2),
XFS_PREALLOC_SYNC = (1 << 3),
XFS_PREALLOC_INVISIBLE = (1 << 4),
};
int xfs_update_prealloc_flags(struct xfs_inode *ip,
enum xfs_prealloc_flags flags);
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-21 05:42:38 +08:00
int xfs_break_layouts(struct inode *inode, uint *iolock,
enum layout_break_reason reason);
xfs: inodes are new until the dentry cache is set up Al Viro noticed a generic set of issues to do with filehandle lookup racing with dentry cache setup. They involve a filehandle lookup occurring while an inode is being created and the filehandle lookup racing with the dentry creation for the real file. This can lead to multiple dentries for the one path being instantiated. There are a host of other issues around this same set of paths. The underlying cause is that file handle lookup only waits on inode cache instantiation rather than full dentry cache instantiation. XFS is mostly immune to the problems discovered due to it's own internal inode cache, but there are a couple of corner cases where races can happen. We currently clear the XFS_INEW flag when the inode is fully set up after insertion into the cache. Newly allocated inodes are inserted locked and so aren't usable until the allocation transaction commits. This, however, occurs before the dentry and security information is fully initialised and hence the inode is unlocked and available for lookups to find too early. To solve the problem, only clear the XFS_INEW flag for newly created inodes once the dentry is fully instantiated. This means lookups will retry until the XFS_INEW flag is removed from the inode and hence avoids the race conditions in questions. THis also means that xfs_create(), xfs_create_tmpfile() and xfs_symlink() need to finish the setup of the inode in their error paths if we had allocated the inode but failed later in the creation process. xfs_symlink(), in particular, needed a lot of help to make it's error handling match that of xfs_create(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 19:38:08 +08:00
/* from xfs_iops.c */
extern void xfs_setup_inode(struct xfs_inode *ip);
extern void xfs_setup_iops(struct xfs_inode *ip);
xfs: inodes are new until the dentry cache is set up Al Viro noticed a generic set of issues to do with filehandle lookup racing with dentry cache setup. They involve a filehandle lookup occurring while an inode is being created and the filehandle lookup racing with the dentry creation for the real file. This can lead to multiple dentries for the one path being instantiated. There are a host of other issues around this same set of paths. The underlying cause is that file handle lookup only waits on inode cache instantiation rather than full dentry cache instantiation. XFS is mostly immune to the problems discovered due to it's own internal inode cache, but there are a couple of corner cases where races can happen. We currently clear the XFS_INEW flag when the inode is fully set up after insertion into the cache. Newly allocated inodes are inserted locked and so aren't usable until the allocation transaction commits. This, however, occurs before the dentry and security information is fully initialised and hence the inode is unlocked and available for lookups to find too early. To solve the problem, only clear the XFS_INEW flag for newly created inodes once the dentry is fully instantiated. This means lookups will retry until the XFS_INEW flag is removed from the inode and hence avoids the race conditions in questions. THis also means that xfs_create(), xfs_create_tmpfile() and xfs_symlink() need to finish the setup of the inode in their error paths if we had allocated the inode but failed later in the creation process. xfs_symlink(), in particular, needed a lot of help to make it's error handling match that of xfs_create(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 19:38:08 +08:00
/*
* When setting up a newly allocated inode, we need to call
* xfs_finish_inode_setup() once the inode is fully instantiated at
* the VFS level to prevent the rest of the world seeing the inode
* before we've completed instantiation. Otherwise we can do it
* the moment the inode lookup is complete.
*/
static inline void xfs_finish_inode_setup(struct xfs_inode *ip)
{
xfs_iflags_clear(ip, XFS_INEW);
barrier();
unlock_new_inode(VFS_I(ip));
wake_up_bit(&ip->i_flags, __XFS_INEW_BIT);
xfs: inodes are new until the dentry cache is set up Al Viro noticed a generic set of issues to do with filehandle lookup racing with dentry cache setup. They involve a filehandle lookup occurring while an inode is being created and the filehandle lookup racing with the dentry creation for the real file. This can lead to multiple dentries for the one path being instantiated. There are a host of other issues around this same set of paths. The underlying cause is that file handle lookup only waits on inode cache instantiation rather than full dentry cache instantiation. XFS is mostly immune to the problems discovered due to it's own internal inode cache, but there are a couple of corner cases where races can happen. We currently clear the XFS_INEW flag when the inode is fully set up after insertion into the cache. Newly allocated inodes are inserted locked and so aren't usable until the allocation transaction commits. This, however, occurs before the dentry and security information is fully initialised and hence the inode is unlocked and available for lookups to find too early. To solve the problem, only clear the XFS_INEW flag for newly created inodes once the dentry is fully instantiated. This means lookups will retry until the XFS_INEW flag is removed from the inode and hence avoids the race conditions in questions. THis also means that xfs_create(), xfs_create_tmpfile() and xfs_symlink() need to finish the setup of the inode in their error paths if we had allocated the inode but failed later in the creation process. xfs_symlink(), in particular, needed a lot of help to make it's error handling match that of xfs_create(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 19:38:08 +08:00
}
static inline void xfs_setup_existing_inode(struct xfs_inode *ip)
{
xfs_setup_inode(ip);
xfs_setup_iops(ip);
xfs: inodes are new until the dentry cache is set up Al Viro noticed a generic set of issues to do with filehandle lookup racing with dentry cache setup. They involve a filehandle lookup occurring while an inode is being created and the filehandle lookup racing with the dentry creation for the real file. This can lead to multiple dentries for the one path being instantiated. There are a host of other issues around this same set of paths. The underlying cause is that file handle lookup only waits on inode cache instantiation rather than full dentry cache instantiation. XFS is mostly immune to the problems discovered due to it's own internal inode cache, but there are a couple of corner cases where races can happen. We currently clear the XFS_INEW flag when the inode is fully set up after insertion into the cache. Newly allocated inodes are inserted locked and so aren't usable until the allocation transaction commits. This, however, occurs before the dentry and security information is fully initialised and hence the inode is unlocked and available for lookups to find too early. To solve the problem, only clear the XFS_INEW flag for newly created inodes once the dentry is fully instantiated. This means lookups will retry until the XFS_INEW flag is removed from the inode and hence avoids the race conditions in questions. THis also means that xfs_create(), xfs_create_tmpfile() and xfs_symlink() need to finish the setup of the inode in their error paths if we had allocated the inode but failed later in the creation process. xfs_symlink(), in particular, needed a lot of help to make it's error handling match that of xfs_create(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 19:38:08 +08:00
xfs_finish_inode_setup(ip);
}
void xfs_irele(struct xfs_inode *ip);
extern struct kmem_zone *xfs_inode_zone;
/* The default CoW extent size hint. */
#define XFS_DEFAULT_COWEXTSZ_HINT 32
bool xfs_inode_verify_forks(struct xfs_inode *ip);
int xfs_iunlink_init(struct xfs_perag *pag);
void xfs_iunlink_destroy(struct xfs_perag *pag);
xfs: implement per-inode writeback completion queues When scheduling writeback of dirty file data in the page cache, XFS uses IO completion workqueue items to ensure that filesystem metadata only updates after the write completes successfully. This is essential for converting unwritten extents to real extents at the right time and performing COW remappings. Unfortunately, XFS queues each IO completion work item to an unbounded workqueue, which means that the kernel can spawn dozens of threads to try to handle the items quickly. These threads need to take the ILOCK to update file metadata, which results in heavy ILOCK contention if a large number of the work items target a single file, which is inefficient. Worse yet, the writeback completion threads get stuck waiting for the ILOCK while holding transaction reservations, which can use up all available log reservation space. When that happens, metadata updates to other parts of the filesystem grind to a halt, even if the filesystem could otherwise have handled it. Even worse, if one of the things grinding to a halt happens to be a thread in the middle of a defer-ops finish holding the same ILOCK and trying to obtain more log reservation having exhausted the permanent reservation, we now have an ABBA deadlock - writeback completion has a transaction reserved and wants the ILOCK, and someone else has the ILOCK and wants a transaction reservation. Therefore, we create a per-inode writeback io completion queue + work item. When writeback finishes, it can add the ioend to the per-inode queue and let the single worker item process that queue. This dramatically cuts down on the number of kworkers and ILOCK contention in the system, and seems to have eliminated an occasional deadlock I was seeing while running generic/476. Testing with a program that simulates a heavy random-write workload to a single file demonstrates that the number of kworkers drops from approximately 120 threads per file to 1, without dramatically changing write bandwidth or pagecache access latency. Note that we leave the xfs-conv workqueue's max_active alone because we still want to be able to run ioend processing for as many inodes as the system can handle. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-16 04:13:20 +08:00
void xfs_end_io(struct work_struct *work);
#endif /* __XFS_INODE_H__ */