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OpenCloudOS-Kernel/fs/ext4/page-io.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
/*
* linux/fs/ext4/page-io.c
*
* This contains the new page_io functions for ext4
*
* Written by Theodore Ts'o, 2010.
*/
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/highuid.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/string.h>
#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include <linux/pagevec.h>
#include <linux/mpage.h>
#include <linux/namei.h>
#include <linux/uio.h>
#include <linux/bio.h>
#include <linux/workqueue.h>
#include <linux/kernel.h>
#include <linux/slab.h>
ext4: use redirty_page_for_writepage() in ext4_bio_write_page() When we cannot write a page we should use redirty_page_for_writepage() instead of plain set_page_dirty(). That tells writeback code we have problems, redirties only the page (redirtying buffers is not needed), and updates mm accounting of failed page writes. Also move clearing of buffer dirty flag after io_submit_add_bh(). At that moment we are sure buffer will be going to disk. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 22:32:54 +08:00
#include <linux/mm.h>
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
#include <linux/backing-dev.h>
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
#include "ext4_jbd2.h"
#include "xattr.h"
#include "acl.h"
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
static struct kmem_cache *io_end_cachep;
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
static struct kmem_cache *io_end_vec_cachep;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4: rename {exit,init}_ext4_*() to ext4_{exit,init}_*() This is a cleanup to avoid namespace leaks out of fs/ext4 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:14 +08:00
int __init ext4_init_pageio(void)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT);
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
if (io_end_cachep == NULL)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
return -ENOMEM;
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
io_end_vec_cachep = KMEM_CACHE(ext4_io_end_vec, 0);
if (io_end_vec_cachep == NULL) {
kmem_cache_destroy(io_end_cachep);
return -ENOMEM;
}
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
return 0;
}
ext4: rename {exit,init}_ext4_*() to ext4_{exit,init}_*() This is a cleanup to avoid namespace leaks out of fs/ext4 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:14 +08:00
void ext4_exit_pageio(void)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
kmem_cache_destroy(io_end_cachep);
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
kmem_cache_destroy(io_end_vec_cachep);
}
struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end)
{
struct ext4_io_end_vec *io_end_vec;
io_end_vec = kmem_cache_zalloc(io_end_vec_cachep, GFP_NOFS);
if (!io_end_vec)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&io_end_vec->list);
list_add_tail(&io_end_vec->list, &io_end->list_vec);
return io_end_vec;
}
static void ext4_free_io_end_vec(ext4_io_end_t *io_end)
{
struct ext4_io_end_vec *io_end_vec, *tmp;
if (list_empty(&io_end->list_vec))
return;
list_for_each_entry_safe(io_end_vec, tmp, &io_end->list_vec, list) {
list_del(&io_end_vec->list);
kmem_cache_free(io_end_vec_cachep, io_end_vec);
}
}
struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end)
{
BUG_ON(list_empty(&io_end->list_vec));
return list_last_entry(&io_end->list_vec, struct ext4_io_end_vec, list);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
/*
* Print an buffer I/O error compatible with the fs/buffer.c. This
* provides compatibility with dmesg scrapers that look for a specific
* buffer I/O error message. We really need a unified error reporting
* structure to userspace ala Digital Unix's uerf system, but it's
* probably not going to happen in my lifetime, due to LKML politics...
*/
static void buffer_io_error(struct buffer_head *bh)
{
fs: use block_device name vsprintf helper Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:37 +08:00
printk_ratelimited(KERN_ERR "Buffer I/O error on device %pg, logical block %llu\n",
bh->b_bdev,
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
(unsigned long long)bh->b_blocknr);
}
static void ext4_finish_bio(struct bio *bio)
{
block: Convert various code to bio_for_each_segment() With immutable biovecs we don't want code accessing bi_io_vec directly - the uses this patch changes weren't incorrect since they all own the bio, but it makes the code harder to audit for no good reason - also, this will help with multipage bvecs later. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-11-08 04:20:26 +08:00
struct bio_vec *bvec;
block: allow bio_for_each_segment_all() to iterate over multi-page bvec This patch introduces one extra iterator variable to bio_for_each_segment_all(), then we can allow bio_for_each_segment_all() to iterate over multi-page bvec. Given it is just one mechannical & simple change on all bio_for_each_segment_all() users, this patch does tree-wide change in one single patch, so that we can avoid to use a temporary helper for this conversion. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-15 19:13:19 +08:00
struct bvec_iter_all iter_all;
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
block: remove the i argument to bio_for_each_segment_all We only have two callers that need the integer loop iterator, and they can easily maintain it themselves. Suggested-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Coly Li <colyli@suse.de> Reviewed-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-25 15:03:00 +08:00
bio_for_each_segment_all(bvec, bio, iter_all) {
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
struct page *page = bvec->bv_page;
fscrypt: simplify bounce page handling Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:39 +08:00
struct page *bounce_page = NULL;
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
struct buffer_head *bh, *head;
unsigned bio_start = bvec->bv_offset;
unsigned bio_end = bio_start + bvec->bv_len;
unsigned under_io = 0;
unsigned long flags;
fscrypt: simplify bounce page handling Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:39 +08:00
if (fscrypt_is_bounce_page(page)) {
bounce_page = page;
page = fscrypt_pagecache_page(bounce_page);
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
}
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
if (bio->bi_status) {
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
SetPageError(page);
fs: use mapping_set_error instead of opencoded set_bit The mapping_set_error() helper sets the correct AS_ flag for the mapping so there is no reason to open code it. Use the helper directly. [akpm@linux-foundation.org: be honest about conversion from -ENXIO to -EIO] Link: http://lkml.kernel.org/r/20160912111608.2588-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-12 04:56:01 +08:00
mapping_set_error(page->mapping, -EIO);
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
}
bh = head = page_buffers(page);
/*
fs/buffer: Make BH_Uptodate_Lock bit_spin_lock a regular spinlock_t Bit spinlocks are problematic if PREEMPT_RT is enabled, because they disable preemption, which is undesired for latency reasons and breaks when regular spinlocks are taken within the bit_spinlock locked region because regular spinlocks are converted to 'sleeping spinlocks' on RT. PREEMPT_RT replaced the bit spinlocks with regular spinlocks to avoid this problem. The replacement was done conditionaly at compile time, but Christoph requested to do an unconditional conversion. Jan suggested to move the spinlock into a existing padding hole which avoids a size increase of struct buffer_head on production kernels. As a benefit the lock gains lockdep coverage. [ bigeasy: Remove the wrapper and use always spinlock_t and move it into the padding hole ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20191118132824.rclhrbujqh4b4g4d@linutronix.de
2019-11-18 21:28:24 +08:00
* We check all buffers in the page under b_uptodate_lock
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
* to avoid races with other end io clearing async_write flags
*/
fs/buffer: Make BH_Uptodate_Lock bit_spin_lock a regular spinlock_t Bit spinlocks are problematic if PREEMPT_RT is enabled, because they disable preemption, which is undesired for latency reasons and breaks when regular spinlocks are taken within the bit_spinlock locked region because regular spinlocks are converted to 'sleeping spinlocks' on RT. PREEMPT_RT replaced the bit spinlocks with regular spinlocks to avoid this problem. The replacement was done conditionaly at compile time, but Christoph requested to do an unconditional conversion. Jan suggested to move the spinlock into a existing padding hole which avoids a size increase of struct buffer_head on production kernels. As a benefit the lock gains lockdep coverage. [ bigeasy: Remove the wrapper and use always spinlock_t and move it into the padding hole ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20191118132824.rclhrbujqh4b4g4d@linutronix.de
2019-11-18 21:28:24 +08:00
spin_lock_irqsave(&head->b_uptodate_lock, flags);
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
do {
if (bh_offset(bh) < bio_start ||
bh_offset(bh) + bh->b_size > bio_end) {
if (buffer_async_write(bh))
under_io++;
continue;
}
clear_buffer_async_write(bh);
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
if (bio->bi_status)
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
buffer_io_error(bh);
} while ((bh = bh->b_this_page) != head);
fs/buffer: Make BH_Uptodate_Lock bit_spin_lock a regular spinlock_t Bit spinlocks are problematic if PREEMPT_RT is enabled, because they disable preemption, which is undesired for latency reasons and breaks when regular spinlocks are taken within the bit_spinlock locked region because regular spinlocks are converted to 'sleeping spinlocks' on RT. PREEMPT_RT replaced the bit spinlocks with regular spinlocks to avoid this problem. The replacement was done conditionaly at compile time, but Christoph requested to do an unconditional conversion. Jan suggested to move the spinlock into a existing padding hole which avoids a size increase of struct buffer_head on production kernels. As a benefit the lock gains lockdep coverage. [ bigeasy: Remove the wrapper and use always spinlock_t and move it into the padding hole ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20191118132824.rclhrbujqh4b4g4d@linutronix.de
2019-11-18 21:28:24 +08:00
spin_unlock_irqrestore(&head->b_uptodate_lock, flags);
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
if (!under_io) {
fscrypt: simplify bounce page handling Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:39 +08:00
fscrypt_free_bounce_page(bounce_page);
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
end_page_writeback(page);
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
}
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
}
}
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
static void ext4_release_io_end(ext4_io_end_t *io_end)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
struct bio *bio, *next_bio;
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
BUG_ON(!list_empty(&io_end->list));
BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
ext4: use transaction reservation for extent conversion in ext4_end_io Later we would like to clear PageWriteback bit only after extent conversion from unwritten to written extents is performed. However it is not possible to start a transaction after PageWriteback is set because that violates lock ordering (and is easy to deadlock). So we have to reserve a transaction before locking pages and sending them for IO and later we use the transaction for extent conversion from ext4_end_io(). Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 01:21:11 +08:00
WARN_ON(io_end->handle);
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
for (bio = io_end->bio; bio; bio = next_bio) {
next_bio = bio->bi_private;
ext4_finish_bio(bio);
bio_put(bio);
}
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
ext4_free_io_end_vec(io_end);
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
kmem_cache_free(io_end_cachep, io_end);
}
ext4: remove wait for unwritten extent conversion from ext4_truncate() Since PageWriteback bit is now cleared after extents are converted from unwritten to written ones, we have full exclusion of writeback path from truncate (truncate_inode_pages() waits for PageWriteback bits to get cleared on all invalidated pages). Exclusion from DIO path is achieved by inode_dio_wait() call in ext4_setattr(). So there's no need to wait for extent convertion in ext4_truncate() anymore. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:30:00 +08:00
/*
* Check a range of space and convert unwritten extents to written. Note that
* we are protected from truncate touching same part of extent tree by the
* fact that truncate code waits for all DIO to finish (thus exclusion from
* direct IO is achieved) and also waits for PageWriteback bits. Thus we
* cannot get to ext4_ext_truncate() before all IOs overlapping that range are
* completed (happens from ext4_free_ioend()).
*/
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
static int ext4_end_io_end(ext4_io_end_t *io_end)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
struct inode *inode = io_end->inode;
handle_t *handle = io_end->handle;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
int ret = 0;
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
ext4_debug("ext4_end_io_nolock: io_end 0x%p from inode %lu,list->next 0x%p,"
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
"list->prev 0x%p\n",
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end, inode->i_ino, io_end->list.next, io_end->list.prev);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end->handle = NULL; /* Following call will use up the handle */
ext4: Add API to bring in support for unwritten io_end_vec conversion This patch just brings in the API for conversion of unwritten io_end_vec extents which will be required for blocksize < pagesize support for dioread_nolock feature. No functional changes in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-3-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:08 +08:00
ret = ext4_convert_unwritten_io_end_vec(handle, io_end);
ext4: add shutdown bit and check for it Add a shutdown bit that will cause ext4 processing to fail immediately with EIO. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-02-05 14:28:48 +08:00
if (ret < 0 && !ext4_forced_shutdown(EXT4_SB(inode->i_sb))) {
ext4: optimize locking for end_io extent conversion Now that we are doing the locking correctly, we need to grab the i_completed_io_lock() twice per end_io. We can clean this up by removing the structure from the i_complted_io_list, and use this as the locking mechanism to prevent ext4_flush_completed_IO() racing against ext4_end_io_work(), instead of clearing the EXT4_IO_END_UNWRITTEN in io->flag. In addition, if the ext4_convert_unwritten_extents() returns an error, we no longer keep the end_io structure on the linked list. This doesn't help, because it tends to lock up the file system and wedges the system. That's one way to call attention to the problem, but it doesn't help the overall robustness of the system. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-31 22:56:32 +08:00
ext4_msg(inode->i_sb, KERN_EMERG,
"failed to convert unwritten extents to written "
"extents -- potential data loss! "
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
"(inode %lu, error %d)", inode->i_ino, ret);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
ext4_clear_io_unwritten_flag(io_end);
ext4_release_io_end(io_end);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
return ret;
}
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
static void dump_completed_IO(struct inode *inode, struct list_head *head)
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
{
#ifdef EXT4FS_DEBUG
struct list_head *cur, *before, *after;
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
ext4_io_end_t *io_end, *io_end0, *io_end1;
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
if (list_empty(head))
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
return;
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
ext4_debug("Dump inode %lu completed io list\n", inode->i_ino);
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
list_for_each_entry(io_end, head, list) {
cur = &io_end->list;
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
before = cur->prev;
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end0 = container_of(before, ext4_io_end_t, list);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
after = cur->next;
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end1 = container_of(after, ext4_io_end_t, list);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n",
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end, inode->i_ino, io_end0, io_end1);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
}
#endif
}
/* Add the io_end to per-inode completed end_io list. */
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
static void ext4_add_complete_io(ext4_io_end_t *io_end)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
struct ext4_inode_info *ei = EXT4_I(io_end->inode);
ext4: fix assertion in ext4_add_complete_io() It doesn't make sense to require io_end->handle when we are in nojournal mode. So update the assertion accordingly to avoid false warnings from ext4_add_complete_io(). Reported-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-10-16 20:25:11 +08:00
struct ext4_sb_info *sbi = EXT4_SB(io_end->inode->i_sb);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
struct workqueue_struct *wq;
unsigned long flags;
direct-io: Implement generic deferred AIO completions Add support to the core direct-io code to defer AIO completions to user context using a workqueue. This replaces opencoded and less efficient code in XFS and ext4 (we save a memory allocation for each direct IO) and will be needed to properly support O_(D)SYNC for AIO. The communication between the filesystem and the direct I/O code requires a new buffer head flag, which is a bit ugly but not avoidable until the direct I/O code stops abusing the buffer_head structure for communicating with the filesystems. Currently this creates a per-superblock unbound workqueue for these completions, which is taken from an earlier patch by Jan Kara. I'm not really convinced about this use and would prefer a "normal" global workqueue with a high concurrency limit, but this needs further discussion. JK: Fixed ext4 part, dynamic allocation of the workqueue. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 21:04:39 +08:00
/* Only reserved conversions from writeback should enter here */
WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN));
ext4: fix assertion in ext4_add_complete_io() It doesn't make sense to require io_end->handle when we are in nojournal mode. So update the assertion accordingly to avoid false warnings from ext4_add_complete_io(). Reported-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-10-16 20:25:11 +08:00
WARN_ON(!io_end->handle && sbi->s_journal);
ext4: Use correct locking for ext4_end_io_nolock() We must hold i_completed_io_lock when manipulating anything on the i_completed_io_list linked list. This includes io->lock, which we were checking in ext4_end_io_nolock(). So move this check to ext4_end_io_work(). This also has the bonus of avoiding extra work if it is already done without needing to take the mutex. Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-31 06:26:08 +08:00
spin_lock_irqsave(&ei->i_completed_io_lock, flags);
ext4: fix assertion in ext4_add_complete_io() It doesn't make sense to require io_end->handle when we are in nojournal mode. So update the assertion accordingly to avoid false warnings from ext4_add_complete_io(). Reported-by: Eric Whitney <enwlinux@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-10-16 20:25:11 +08:00
wq = sbi->rsv_conversion_wq;
direct-io: Implement generic deferred AIO completions Add support to the core direct-io code to defer AIO completions to user context using a workqueue. This replaces opencoded and less efficient code in XFS and ext4 (we save a memory allocation for each direct IO) and will be needed to properly support O_(D)SYNC for AIO. The communication between the filesystem and the direct I/O code requires a new buffer head flag, which is a bit ugly but not avoidable until the direct I/O code stops abusing the buffer_head structure for communicating with the filesystems. Currently this creates a per-superblock unbound workqueue for these completions, which is taken from an earlier patch by Jan Kara. I'm not really convinced about this use and would prefer a "normal" global workqueue with a high concurrency limit, but this needs further discussion. JK: Fixed ext4 part, dynamic allocation of the workqueue. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 21:04:39 +08:00
if (list_empty(&ei->i_rsv_conversion_list))
queue_work(wq, &ei->i_rsv_conversion_work);
list_add_tail(&io_end->list, &ei->i_rsv_conversion_list);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
}
ext4: Use correct locking for ext4_end_io_nolock() We must hold i_completed_io_lock when manipulating anything on the i_completed_io_list linked list. This includes io->lock, which we were checking in ext4_end_io_nolock(). So move this check to ext4_end_io_work(). This also has the bonus of avoiding extra work if it is already done without needing to take the mutex. Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-31 06:26:08 +08:00
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
static int ext4_do_flush_completed_IO(struct inode *inode,
struct list_head *head)
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
{
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
ext4_io_end_t *io_end;
ext4: simplify list handling in ext4_do_flush_completed_IO() The function splices i_completed_io_list to its private list first. From that moment on we don't need any lock for working with io_end structures because all io_end structure on the list are only our own. So we can remove the other two lists in the function and free io_end immediately after we are done with it. CC: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 22:49:15 +08:00
struct list_head unwritten;
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
unsigned long flags;
struct ext4_inode_info *ei = EXT4_I(inode);
int err, ret = 0;
spin_lock_irqsave(&ei->i_completed_io_lock, flags);
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
dump_completed_IO(inode, head);
list_replace_init(head, &unwritten);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
while (!list_empty(&unwritten)) {
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
io_end = list_entry(unwritten.next, ext4_io_end_t, list);
BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN));
list_del_init(&io_end->list);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
err = ext4_end_io_end(io_end);
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
if (unlikely(!ret && err))
ret = err;
}
return ret;
}
/*
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
* work on completed IO, to convert unwritten extents to extents
ext4: completed_io locking cleanup Current unwritten extent conversion state-machine is very fuzzy. - For unknown reason it performs conversion under i_mutex. What for? My diagnosis: We already protect extent tree with i_data_sem, truncate and punch_hole should wait for DIO, so the only data we have to protect is end_io->flags modification, but only flush_completed_IO and end_io_work modified this flags and we can serialize them via i_completed_io_lock. Currently all these games with mutex_trylock result in the following deadlock truncate: kworker: ext4_setattr ext4_end_io_work mutex_lock(i_mutex) inode_dio_wait(inode) ->BLOCK DEADLOCK<- mutex_trylock() inode_dio_done() #TEST_CASE1_BEGIN MNT=/mnt_scrach unlink $MNT/file fallocate -l $((1024*1024*1024)) $MNT/file aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file sleep 2 truncate -s 0 $MNT/file #TEST_CASE1_END Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286 This patch makes state machine simple and clean: (1) xxx_end_io schedule final extent conversion simply by calling ext4_add_complete_io(), which append it to ei->i_completed_io_list NOTE1: because of (2A) work should be queued only if ->i_completed_io_list was empty, otherwise the work is scheduled already. (2) ext4_flush_completed_IO is responsible for handling all pending end_io from ei->i_completed_io_list Flushing sequence consists of following stages: A) LOCKED: Atomically drain completed_io_list to local_list B) Perform extents conversion C) LOCKED: move converted io's to to_free list for final deletion This logic depends on context which we was called from. D) Final end_io context destruction NOTE1: i_mutex is no longer required because end_io->flags modification is protected by ei->ext4_complete_io_lock Full list of changes: - Move all completion end_io related routines to page-io.c in order to improve logic locality - Move open coded logic from various xx_end_xx routines to ext4_add_complete_io() - remove EXT4_IO_END_FSYNC - Improve SMP scalability by removing useless i_mutex which does not protect io->flags anymore. - Reduce lock contention on i_completed_io_lock by optimizing list walk. - Rename ext4_end_io_nolock to end4_end_io and make it static - Check flush completion status to ext4_ext_punch_hole(). Because it is not good idea to punch blocks from corrupted inode. Changes since V3 (in request to Jan's comments): Fall back to active flush_completed_IO() approach in order to prevent performance issues with nolocked DIO reads. Changes since V2: Fix use-after-free caused by race truncate vs end_io_work Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 12:14:55 +08:00
*/
ext4: split extent conversion lists to reserved & unreserved parts Now that we have extent conversions with reserved transaction, we have to prevent extent conversions without reserved transaction (from DIO code) to block these (as that would effectively void any transaction reservation we did). So split lists, work items, and work queues to reserved and unreserved parts. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:21:02 +08:00
void ext4_end_io_rsv_work(struct work_struct *work)
{
struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info,
i_rsv_conversion_work);
ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list);
}
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags)
{
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
ext4_io_end_t *io_end = kmem_cache_zalloc(io_end_cachep, flags);
if (io_end) {
io_end->inode = inode;
INIT_LIST_HEAD(&io_end->list);
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
INIT_LIST_HEAD(&io_end->list_vec);
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
atomic_set(&io_end->count, 1);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: keep uniform naming convention for io & io_end variables Let's keep uniform naming convention for ext4_submit_io (io) & ext4_end_io_t (io_end) structures, to avoid any confusion. No functionality change in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-2-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:07 +08:00
return io_end;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
void ext4_put_io_end_defer(ext4_io_end_t *io_end)
{
if (atomic_dec_and_test(&io_end->count)) {
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) ||
list_empty(&io_end->list_vec)) {
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
ext4_release_io_end(io_end);
return;
}
ext4_add_complete_io(io_end);
}
}
int ext4_put_io_end(ext4_io_end_t *io_end)
{
int err = 0;
if (atomic_dec_and_test(&io_end->count)) {
if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
ext4: Add API to bring in support for unwritten io_end_vec conversion This patch just brings in the API for conversion of unwritten io_end_vec extents which will be required for blocksize < pagesize support for dioread_nolock feature. No functional changes in this patch. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-3-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:08 +08:00
err = ext4_convert_unwritten_io_end_vec(io_end->handle,
io_end);
ext4: use transaction reservation for extent conversion in ext4_end_io Later we would like to clear PageWriteback bit only after extent conversion from unwritten to written extents is performed. However it is not possible to start a transaction after PageWriteback is set because that violates lock ordering (and is easy to deadlock). So we have to reserve a transaction before locking pages and sending them for IO and later we use the transaction for extent conversion from ext4_end_io(). Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 01:21:11 +08:00
io_end->handle = NULL;
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
ext4_clear_io_unwritten_flag(io_end);
}
ext4_release_io_end(io_end);
}
return err;
}
ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end)
{
atomic_inc(&io_end->count);
return io_end;
}
ext4: fix warning in ext4_evict_inode() The following race can lead to ext4_evict_inode() seeing i_ioend_count > 0 and thus triggering a sanity check warning: CPU1 CPU2 ext4_end_bio() ext4_evict_inode() ext4_finish_bio() end_page_writeback(); truncate_inode_pages() evict page WARN_ON(i_ioend_count > 0); ext4_put_io_end_defer() ext4_release_io_end() dec i_ioend_count This is possible use-after-free bug since we decrement i_ioend_count in possibly released inode. Since i_ioend_count is used only for sanity checks one possible solution would be to just remove it but for now I'd like to keep those sanity checks to help debugging the new ext4 writeback code. This patch changes ext4_end_bio() to call ext4_put_io_end_defer() before ext4_finish_bio() in the shortcut case when unwritten extent conversion isn't needed. In that case we don't need the io_end so we are safe to drop it early. Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-07-11 09:31:04 +08:00
/* BIO completion function for page writeback */
block: add a bi_error field to struct bio Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-20 21:29:37 +08:00
static void ext4_end_bio(struct bio *bio)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
ext4_io_end_t *io_end = bio->bi_private;
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-12 06:44:27 +08:00
sector_t bi_sector = bio->bi_iter.bi_sector;
ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio() Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in the ext4_end_bio() function. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-01 08:08:05 +08:00
char b[BDEVNAME_SIZE];
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio() Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in the ext4_end_bio() function. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-01 08:08:05 +08:00
if (WARN_ONCE(!io_end, "io_end is NULL: %s: sector %Lu len %u err %d\n",
block: replace bi_bdev with a gendisk pointer and partitions index This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 01:10:32 +08:00
bio_devname(bio, b),
ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio() Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in the ext4_end_bio() function. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-01 08:08:05 +08:00
(long long) bio->bi_iter.bi_sector,
(unsigned) bio_sectors(bio),
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
bio->bi_status)) {
ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio() Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in the ext4_end_bio() function. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-01 08:08:05 +08:00
ext4_finish_bio(bio);
bio_put(bio);
return;
}
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
bio->bi_end_io = NULL;
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
if (bio->bi_status) {
ext4: defer clearing of PageWriteback after extent conversion Currently PageWriteback bit gets cleared from put_io_page() called from ext4_end_bio(). This is somewhat inconvenient as extent tree is not fully updated at that time (unwritten extents are not marked as written) so we cannot read the data back yet. This design was dictated by lock ordering as we cannot start a transaction while PageWriteback bit is set (we could easily deadlock with ext4_da_writepages()). But now that we use transaction reservation for extent conversion, locking issues are solved and we can move PageWriteback bit clearing after extent conversion is done. As a result we can remove wait for unwritten extent conversion from ext4_sync_file() because it already implicitely happens through wait_on_page_writeback(). We implement deferring of PageWriteback clearing by queueing completed bios to appropriate io_end and processing all the pages when io_end is going to be freed instead of at the moment ext4_io_end() is called. Reviewed-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-05 02:23:41 +08:00
struct inode *inode = io_end->inode;
ext4: note the error in ext4_end_bio() ext4_end_bio() currently throws away the error that it receives. Chances are this is part of a spate of errors, one of which will end up getting the error returned to userspace somehow, but we shouldn't take that risk. Also print out the errno to aid in debug. Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org
2014-04-07 22:54:20 +08:00
ext4_warning(inode->i_sb, "I/O error %d writing to inode %lu "
ext4: Add support for blocksize < pagesize in dioread_nolock This patch adds the support for blocksize < pagesize for dioread_nolock feature. Since in case of blocksize < pagesize, we can have multiple small buffers of page as unwritten extents, we need to maintain a vector of these unwritten extents which needs the conversion after the IO is complete. Thus, we maintain a list of tuple <offset, size> pair (io_end_vec) for this & traverse this list to do the unwritten to written conversion. Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-16 15:37:10 +08:00
"starting block %llu)",
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
bio->bi_status, inode->i_ino,
ext4: handle writeback of inodes which are being freed The following BUG can occur when an inode which is getting freed when it still has dirty pages outstanding, and it gets deleted (in this because it was the target of a rename). In ordered mode, we need to make sure the data pages are written just in case we crash before the rename (or unlink) is committed. If the inode is being freed then when we try to igrab the inode, we end up tripping the BUG_ON at fs/ext4/page-io.c:146. To solve this problem, we need to keep track of the number of io callbacks which are pending, and avoid destroying the inode until they have all been completed. That way we don't have to bump the inode count to keep the inode from being destroyed; an approach which doesn't work because the count could have already been dropped down to zero before the inode writeback has started (at which point we're not allowed to bump the count back up to 1, since it's already started getting freed). Thanks to Dave Chinner for suggesting this approach, which is also used by XFS. kernel BUG at /scratch_space/linux-2.6/fs/ext4/page-io.c:146! Call Trace: [<ffffffff811075b1>] ext4_bio_write_page+0x172/0x307 [<ffffffff811033a7>] mpage_da_submit_io+0x2f9/0x37b [<ffffffff811068d7>] mpage_da_map_and_submit+0x2cc/0x2e2 [<ffffffff811069b3>] mpage_add_bh_to_extent+0xc6/0xd5 [<ffffffff81106c66>] write_cache_pages_da+0x2a4/0x3ac [<ffffffff81107044>] ext4_da_writepages+0x2d6/0x44d [<ffffffff81087910>] do_writepages+0x1c/0x25 [<ffffffff810810a4>] __filemap_fdatawrite_range+0x4b/0x4d [<ffffffff810815f5>] filemap_fdatawrite_range+0xe/0x10 [<ffffffff81122a2e>] jbd2_journal_begin_ordered_truncate+0x7b/0xa2 [<ffffffff8110615d>] ext4_evict_inode+0x57/0x24c [<ffffffff810c14a3>] evict+0x22/0x92 [<ffffffff810c1a3d>] iput+0x212/0x249 [<ffffffff810bdf16>] dentry_iput+0xa1/0xb9 [<ffffffff810bdf6b>] d_kill+0x3d/0x5d [<ffffffff810be613>] dput+0x13a/0x147 [<ffffffff810b990d>] sys_renameat+0x1b5/0x258 [<ffffffff81145f71>] ? _atomic_dec_and_lock+0x2d/0x4c [<ffffffff810b2950>] ? cp_new_stat+0xde/0xea [<ffffffff810b29c1>] ? sys_newlstat+0x2d/0x38 [<ffffffff810b99c6>] sys_rename+0x16/0x18 [<ffffffff81002a2b>] system_call_fastpath+0x16/0x1b Reported-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Tested-by: Nick Bowler <nbowler@elliptictech.com>
2010-11-09 02:43:33 +08:00
(unsigned long long)
ext4: Fix data corruption with multi-block writepages support This fixes a corruption problem with the multi-block writepages submittal change for ext4, from commit bd2d0210cf22f2bd0cef72eb97cf94fc7d31d8cc ("ext4: use bio layer instead of buffer layer in mpage_da_submit_io"). (Note that this corruption is not present in 2.6.37 on ext4, because the corruption was detected after the feature was merged in 2.6.37-rc1, and so it was turned off by adding a non-default mount option, mblk_io_submit. With this commit, which hopefully fixes the last of the bugs with this feature, we'll be able to turn on this performance feature by default in 2.6.38, and remove the mblk_io_submit option.) The ext4 code path to bundle multiple pages for writeback in ext4_bio_write_page() had a bug: we should be clearing buffer head dirty flags *before* we submit the bio, not in the completion routine. The patch below was tested on 2.6.37 under KVM with the postgresql script which was submitted by Jon Nelson as documented in commit 1449032be1. Without the patch, I'd hit the corruption problem about 50-70% of the time. With the patch, I executed the script > 100 times with no corruption seen. I also fixed a bug to make sure ext4_end_bio() doesn't dereference the bio after the bio_put() call. Reported-by: Jon Nelson <jnelson@jamponi.net> Reported-by: Matthias Bayer <jackdachef@gmail.com> Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2011-02-08 01:46:14 +08:00
bi_sector >> (inode->i_blkbits - 9));
block: switch bios to blk_status_t Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 15:38:06 +08:00
mapping_set_error(inode->i_mapping,
blk_status_to_errno(bio->bi_status));
ext4: handle writeback of inodes which are being freed The following BUG can occur when an inode which is getting freed when it still has dirty pages outstanding, and it gets deleted (in this because it was the target of a rename). In ordered mode, we need to make sure the data pages are written just in case we crash before the rename (or unlink) is committed. If the inode is being freed then when we try to igrab the inode, we end up tripping the BUG_ON at fs/ext4/page-io.c:146. To solve this problem, we need to keep track of the number of io callbacks which are pending, and avoid destroying the inode until they have all been completed. That way we don't have to bump the inode count to keep the inode from being destroyed; an approach which doesn't work because the count could have already been dropped down to zero before the inode writeback has started (at which point we're not allowed to bump the count back up to 1, since it's already started getting freed). Thanks to Dave Chinner for suggesting this approach, which is also used by XFS. kernel BUG at /scratch_space/linux-2.6/fs/ext4/page-io.c:146! Call Trace: [<ffffffff811075b1>] ext4_bio_write_page+0x172/0x307 [<ffffffff811033a7>] mpage_da_submit_io+0x2f9/0x37b [<ffffffff811068d7>] mpage_da_map_and_submit+0x2cc/0x2e2 [<ffffffff811069b3>] mpage_add_bh_to_extent+0xc6/0xd5 [<ffffffff81106c66>] write_cache_pages_da+0x2a4/0x3ac [<ffffffff81107044>] ext4_da_writepages+0x2d6/0x44d [<ffffffff81087910>] do_writepages+0x1c/0x25 [<ffffffff810810a4>] __filemap_fdatawrite_range+0x4b/0x4d [<ffffffff810815f5>] filemap_fdatawrite_range+0xe/0x10 [<ffffffff81122a2e>] jbd2_journal_begin_ordered_truncate+0x7b/0xa2 [<ffffffff8110615d>] ext4_evict_inode+0x57/0x24c [<ffffffff810c14a3>] evict+0x22/0x92 [<ffffffff810c1a3d>] iput+0x212/0x249 [<ffffffff810bdf16>] dentry_iput+0xa1/0xb9 [<ffffffff810bdf6b>] d_kill+0x3d/0x5d [<ffffffff810be613>] dput+0x13a/0x147 [<ffffffff810b990d>] sys_renameat+0x1b5/0x258 [<ffffffff81145f71>] ? _atomic_dec_and_lock+0x2d/0x4c [<ffffffff810b2950>] ? cp_new_stat+0xde/0xea [<ffffffff810b29c1>] ? sys_newlstat+0x2d/0x38 [<ffffffff810b99c6>] sys_rename+0x16/0x18 [<ffffffff81002a2b>] system_call_fastpath+0x16/0x1b Reported-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Tested-by: Nick Bowler <nbowler@elliptictech.com>
2010-11-09 02:43:33 +08:00
}
ext4: fix warning in ext4_evict_inode() The following race can lead to ext4_evict_inode() seeing i_ioend_count > 0 and thus triggering a sanity check warning: CPU1 CPU2 ext4_end_bio() ext4_evict_inode() ext4_finish_bio() end_page_writeback(); truncate_inode_pages() evict page WARN_ON(i_ioend_count > 0); ext4_put_io_end_defer() ext4_release_io_end() dec i_ioend_count This is possible use-after-free bug since we decrement i_ioend_count in possibly released inode. Since i_ioend_count is used only for sanity checks one possible solution would be to just remove it but for now I'd like to keep those sanity checks to help debugging the new ext4 writeback code. This patch changes ext4_end_bio() to call ext4_put_io_end_defer() before ext4_finish_bio() in the shortcut case when unwritten extent conversion isn't needed. In that case we don't need the io_end so we are safe to drop it early. Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-07-11 09:31:04 +08:00
if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
/*
* Link bio into list hanging from io_end. We have to do it
* atomically as bio completions can be racing against each
* other.
*/
bio->bi_private = xchg(&io_end->bio, bio);
ext4_put_io_end_defer(io_end);
} else {
/*
* Drop io_end reference early. Inode can get freed once
* we finish the bio.
*/
ext4_put_io_end_defer(io_end);
ext4_finish_bio(bio);
bio_put(bio);
}
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
void ext4_io_submit(struct ext4_io_submit *io)
{
struct bio *bio = io->io_bio;
if (bio) {
block, fs, mm, drivers: use bio set/get op accessors This patch converts the simple bi_rw use cases in the block, drivers, mm and fs code to set/get the bio operation using bio_set_op_attrs/bio_op These should be simple one or two liner cases, so I just did them in one patch. The next patches handle the more complicated cases in a module per patch. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-06 03:31:48 +08:00
int io_op_flags = io->io_wbc->sync_mode == WB_SYNC_ALL ?
block,fs: use REQ_* flags directly Remove the WRITE_* and READ_SYNC wrappers, and just use the flags directly. Where applicable this also drops usage of the bio_set_op_attrs wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01 21:40:10 +08:00
REQ_SYNC : 0;
ext4: add support for passing in write hints for buffered writes Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 23:32:37 +08:00
io->io_bio->bi_write_hint = io->io_end->inode->i_write_hint;
block, fs, mm, drivers: use bio set/get op accessors This patch converts the simple bi_rw use cases in the block, drivers, mm and fs code to set/get the bio operation using bio_set_op_attrs/bio_op These should be simple one or two liner cases, so I just did them in one patch. The next patches handle the more complicated cases in a module per patch. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-06 03:31:48 +08:00
bio_set_op_attrs(io->io_bio, REQ_OP_WRITE, io_op_flags);
block/fs/drivers: remove rw argument from submit_bio This has callers of submit_bio/submit_bio_wait set the bio->bi_rw instead of passing it in. This makes that use the same as generic_make_request and how we set the other bio fields. Signed-off-by: Mike Christie <mchristi@redhat.com> Fixed up fs/ext4/crypto.c Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-06 03:31:41 +08:00
submit_bio(io->io_bio);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: Fix sparse warning: Using plain integer as NULL pointer This patch fixes the warning "Using plain integer as NULL pointer", generated by sparse, by replacing the offending 0s with NULL. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-22 10:01:42 +08:00
io->io_bio = NULL;
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
}
void ext4_io_submit_init(struct ext4_io_submit *io,
struct writeback_control *wbc)
{
ext4: replace ext4_io_submit->io_op with ->io_wbc ext4_io_submit_init() takes the pointer to writeback_control to test its sync_mode and determine between WRITE and WRITE_SYNC and records the result in ->io_op. This patch makes it record the pointer directly and moves the test to ext4_io_submit(). This doesn't cause any noticeable differences now but having writeback_control available throughout IO submission path will be depended upon by the planned cgroup writeback support. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-07-22 11:50:24 +08:00
io->io_wbc = wbc;
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
io->io_bio = NULL;
ext4: Fix sparse warning: Using plain integer as NULL pointer This patch fixes the warning "Using plain integer as NULL pointer", generated by sparse, by replacing the offending 0s with NULL. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-22 10:01:42 +08:00
io->io_end = NULL;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
static void io_submit_init_bio(struct ext4_io_submit *io,
struct buffer_head *bh)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
struct bio *bio;
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
/*
* bio_alloc will _always_ be able to allocate a bio if
* __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
*/
block: rename BIO_MAX_PAGES to BIO_MAX_VECS Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop confusing users of the bio API. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-11 19:01:37 +08:00
bio = bio_alloc(GFP_NOIO, BIO_MAX_VECS);
ext4: add inline encryption support Wire up ext4 to support inline encryption via the helper functions which fs/crypto/ now provides. This includes: - Adding a mount option 'inlinecrypt' which enables inline encryption on encrypted files where it can be used. - Setting the bio_crypt_ctx on bios that will be submitted to an inline-encrypted file. Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for this part, since ext4 sometimes uses ll_rw_block() on file data. - Not adding logically discontiguous data to bios that will be submitted to an inline-encrypted file. - Not doing filesystem-layer crypto on inline-encrypted files. Co-developed-by: Satya Tangirala <satyat@google.com> Signed-off-by: Satya Tangirala <satyat@google.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/20200702015607.1215430-5-satyat@google.com Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-07-02 09:56:07 +08:00
fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-12 06:44:27 +08:00
bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
block: replace bi_bdev with a gendisk pointer and partitions index This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 01:10:32 +08:00
bio_set_dev(bio, bh->b_bdev);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
bio->bi_end_io = ext4_end_bio;
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
bio->bi_private = ext4_get_io_end(io->io_end);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
io->io_bio = bio;
io->io_next_block = bh->b_blocknr;
blkcg: associate writeback bios with a blkg One of the goals of this series is to remove a separate reference to the css of the bio. This can and should be accessed via bio_blkcg(). In this patch, wbc_init_bio() now requires a bio to have a device associated with it. Signed-off-by: Dennis Zhou <dennis@kernel.org> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-06 01:10:34 +08:00
wbc_init_bio(io->io_wbc, bio);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
static void io_submit_add_bh(struct ext4_io_submit *io,
struct inode *inode,
struct page *page,
struct buffer_head *bh)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
int ret;
ext4: add inline encryption support Wire up ext4 to support inline encryption via the helper functions which fs/crypto/ now provides. This includes: - Adding a mount option 'inlinecrypt' which enables inline encryption on encrypted files where it can be used. - Setting the bio_crypt_ctx on bios that will be submitted to an inline-encrypted file. Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for this part, since ext4 sometimes uses ll_rw_block() on file data. - Not adding logically discontiguous data to bios that will be submitted to an inline-encrypted file. - Not doing filesystem-layer crypto on inline-encrypted files. Co-developed-by: Satya Tangirala <satyat@google.com> Signed-off-by: Satya Tangirala <satyat@google.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/20200702015607.1215430-5-satyat@google.com Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-07-02 09:56:07 +08:00
if (io->io_bio && (bh->b_blocknr != io->io_next_block ||
!fscrypt_mergeable_bio_bh(io->io_bio, bh))) {
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
submit_and_retry:
ext4_io_submit(io);
}
if (io->io_bio == NULL) {
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
io_submit_init_bio(io, bh);
ext4: add support for passing in write hints for buffered writes Reviewed-by: Andreas Dilger <adilger@dilger.ca> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 23:32:37 +08:00
io->io_bio->bi_write_hint = inode->i_write_hint;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
}
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh));
ext4: use io_end for multiple bios Change writeback path to create just one io_end structure for the extent to which we submit IO and share it among bios writing that extent. This prevents needless splitting and joining of unwritten extents when they cannot be submitted as a single bio. Bugs in ENOMEM handling found by Linux File System Verification project (linuxtesting.org) and fixed by Alexey Khoroshilov <khoroshilov@ispras.ru>. CC: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-06-04 23:58:58 +08:00
if (ret != bh->b_size)
goto submit_and_retry;
blkcg, writeback: Rename wbc_account_io() to wbc_account_cgroup_owner() wbc_account_io() does a very specific job - try to see which cgroup is actually dirtying an inode and transfer its ownership to the majority dirtier if needed. The name is too generic and confusing. Let's rename it to something more specific. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 04:39:49 +08:00
wbc_account_cgroup_owner(io->io_wbc, page, bh->b_size);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
io->io_next_block++;
}
int ext4_bio_write_page(struct ext4_io_submit *io,
struct page *page,
int len,
ext4: fix data integrity sync in ordered mode When we perform a data integrity sync we tag all the dirty pages with PAGECACHE_TAG_TOWRITE at start of ext4_da_writepages. Later we check for this tag in write_cache_pages_da and creates a struct mpage_da_data containing contiguously indexed pages tagged with this tag and sync these pages with a call to mpage_da_map_and_submit. This process is done in while loop until all the PAGECACHE_TAG_TOWRITE pages are synced. We also do journal start and stop in each iteration. journal_stop could initiate journal commit which would call ext4_writepage which in turn will call ext4_bio_write_page even for delayed OR unwritten buffers. When ext4_bio_write_page is called for such buffers, even though it does not sync them but it clears the PAGECACHE_TAG_TOWRITE of the corresponding page and hence these pages are also not synced by the currently running data integrity sync. We will end up with dirty pages although sync is completed. This could cause a potential data loss when the sync call is followed by a truncate_pagecache call, which is exactly the case in collapse_range. (It will cause generic/127 failure in xfstests) To avoid this issue, we can use set_page_writeback_keepwrite instead of set_page_writeback, which doesn't clear TOWRITE tag. Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2014-05-12 20:12:25 +08:00
bool keep_towrite)
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
{
fscrypt: simplify bounce page handling Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:39 +08:00
struct page *bounce_page = NULL;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
struct inode *inode = page->mapping->host;
ext4: remove unused variable Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
2016-09-30 14:14:56 +08:00
unsigned block_start;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
struct buffer_head *bh, *head;
int ret = 0;
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
int nr_submitted = 0;
ext4 crypto: fix memory leak in ext4_bio_write_page() There are times when ext4_bio_write_page() is called even though we don't actually need to do any I/O. This happens when ext4_writepage() gets called by the jbd2 commit path when an inode needs to force its pages written out in order to provide data=ordered guarantees --- and a page is backed by an unwritten (e.g., uninitialized) block on disk, or if delayed allocation means the page's backing store hasn't been allocated yet. In that case, we need to skip the call to ext4_encrypt_page(), since in addition to wasting CPU, it leads to a bounce page and an ext4 crypto context getting leaked. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2015-10-03 11:54:58 +08:00
int nr_to_submit = 0;
ext4: remove unnecessary wbc parameter from ext4_bio_write_page ext4_bio_write_page does not need wbc parameter, since its parameter io contains the io_wbc field. The io::io_wbc is initialized by ext4_io_submit_init which is called in ext4_writepages and ext4_writepage functions prior to ext4_bio_write_page. Therefor, when ext4_bio_write_page is called, wbc info has already been included in io parameter. Signed-off-by: Lei Chen <lennychen@tencent.com> Link: https://lore.kernel.org/r/1607669664-25656-1-git-send-email-lennychen@tencent.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-12-11 14:54:24 +08:00
struct writeback_control *wbc = io->io_wbc;
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4: Fix data corruption with multi-block writepages support This fixes a corruption problem with the multi-block writepages submittal change for ext4, from commit bd2d0210cf22f2bd0cef72eb97cf94fc7d31d8cc ("ext4: use bio layer instead of buffer layer in mpage_da_submit_io"). (Note that this corruption is not present in 2.6.37 on ext4, because the corruption was detected after the feature was merged in 2.6.37-rc1, and so it was turned off by adding a non-default mount option, mblk_io_submit. With this commit, which hopefully fixes the last of the bugs with this feature, we'll be able to turn on this performance feature by default in 2.6.38, and remove the mblk_io_submit option.) The ext4 code path to bundle multiple pages for writeback in ext4_bio_write_page() had a bug: we should be clearing buffer head dirty flags *before* we submit the bio, not in the completion routine. The patch below was tested on 2.6.37 under KVM with the postgresql script which was submitted by Jon Nelson as documented in commit 1449032be1. Without the patch, I'd hit the corruption problem about 50-70% of the time. With the patch, I executed the script > 100 times with no corruption seen. I also fixed a bug to make sure ext4_end_bio() doesn't dereference the bio after the bio_put() call. Reported-by: Jon Nelson <jnelson@jamponi.net> Reported-by: Matthias Bayer <jackdachef@gmail.com> Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2011-02-08 01:46:14 +08:00
BUG_ON(!PageLocked(page));
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
BUG_ON(PageWriteback(page));
ext4: fix data integrity sync in ordered mode When we perform a data integrity sync we tag all the dirty pages with PAGECACHE_TAG_TOWRITE at start of ext4_da_writepages. Later we check for this tag in write_cache_pages_da and creates a struct mpage_da_data containing contiguously indexed pages tagged with this tag and sync these pages with a call to mpage_da_map_and_submit. This process is done in while loop until all the PAGECACHE_TAG_TOWRITE pages are synced. We also do journal start and stop in each iteration. journal_stop could initiate journal commit which would call ext4_writepage which in turn will call ext4_bio_write_page even for delayed OR unwritten buffers. When ext4_bio_write_page is called for such buffers, even though it does not sync them but it clears the PAGECACHE_TAG_TOWRITE of the corresponding page and hence these pages are also not synced by the currently running data integrity sync. We will end up with dirty pages although sync is completed. This could cause a potential data loss when the sync call is followed by a truncate_pagecache call, which is exactly the case in collapse_range. (It will cause generic/127 failure in xfstests) To avoid this issue, we can use set_page_writeback_keepwrite instead of set_page_writeback, which doesn't clear TOWRITE tag. Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2014-05-12 20:12:25 +08:00
if (keep_towrite)
set_page_writeback_keepwrite(page);
else
set_page_writeback(page);
ext4: don't leave PageWriteback set after memory failure In ext4_bio_write_page(), if the memory allocation for the struct ext4_io_page fails, it returns with the page's PageWriteback flag set. This will end up causing the page not to skip writeback in WB_SYNC_NONE mode, and in WB_SYNC_ALL mode (i.e., on a sync, fsync, or umount) the writeback daemon will get stuck forever on the wait_on_page_writeback() function in write_cache_pages_da(). Or, if journalling is enabled and the file gets deleted, it the journal thread can get stuck in journal_finish_inode_data_buffers() call to filemap_fdatawait(). Another place where things can get hung up is in truncate_inode_pages(), called out of ext4_evict_inode(). Fix this by not setting PageWriteback until after we have successfully allocated the struct ext4_io_page. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-02-28 05:43:24 +08:00
ClearPageError(page);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
ext4: fix zeroing of page during writeback Tail of a page straddling inode size must be zeroed when being written out due to POSIX requirement that modifications of mmaped page beyond inode size must not be written to the file. ext4_bio_write_page() did this only for blocks fully beyond inode size but didn't properly zero blocks partially beyond inode size. Fix this. The problem has been uncovered by mmap_11-4 test in openposix test suite (part of LTP). Reported-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com> Fixes: 5a0dc7365c240 Fixes: bd2d0210cf22f CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-28 00:48:55 +08:00
/*
Clean ups and miscellaneous bug fixes, in particular for the new collapse_range and zero_range fallocate functions. In addition, improve the scalability of adding and remove inodes from the orphan list. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAABCAAGBQJTk9x7AAoJENNvdpvBGATwQQ4QAN85xkNWWiq0feLGZjUVTre/ JUgRQWXZYVogAQckQoTDXqJt1qKYxO45A8oIoUMI4uzgcFJm7iJIZJAv3Hjd2ftz 48RVwjWHblmBz6e+CdmETpzJUaJr3KXbnk3EDQzagWg3Q64dBU/yT0c4foBO8wfX FI1MNin70r5NGQv6Mp4xNUfMoU6liCrsMO2RWkyxY2rcmxy6tkpNO/NBAPwhmn0e vwKHvnnqKM08Frrt6Lz3MpXGAJ+rhTSvmL+qSRXQn9BcbphdGa4jy+i3HbviRX4N z77UZMgMbfK1V3YHm8KzmmbIHrmIARXUlCM7jp4HPSnb4qhyERrhVmGCJZ8civ6Q 3Cm9WwA93PQDfRX6Kid3K1tR/ql+ryac55o9SM990osrWp4C0IH+P/CdlSN0GspN 3pJTLHUVVcxF6gSnOD+q/JzM8Iudl87Rxb17wA+6eg3AJRaPoQSPJoqtwZ89ZwOz RiZGuugFp7gDOxqo32lJ53fivO/e1zxXxu0dVHHjOnHBVWX063hlcibTg8kvFWg1 7bBvUkvgT5jR+UuDX81wPZ+c0kkmfk4gxT5sHg6RlMKeCYi3uuLmAYgla3AM4j9G GeNNdVTmilH7wMgYB2wxd0C5HofgKgM5YFLZWc0FVSXMeFs5ST2kbLMXAZqzrKPa szHFEJHIGZByXfkP/jix =C1ZV -----END PGP SIGNATURE----- Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Clean ups and miscellaneous bug fixes, in particular for the new collapse_range and zero_range fallocate functions. In addition, improve the scalability of adding and remove inodes from the orphan list" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits) ext4: handle symlink properly with inline_data ext4: fix wrong assert in ext4_mb_normalize_request() ext4: fix zeroing of page during writeback ext4: remove unused local variable "stored" from ext4_readdir(...) ext4: fix ZERO_RANGE test failure in data journalling ext4: reduce contention on s_orphan_lock ext4: use sbi in ext4_orphan_{add|del}() ext4: use EXT_MAX_BLOCKS in ext4_es_can_be_merged() ext4: add missing BUFFER_TRACE before ext4_journal_get_write_access ext4: remove unnecessary double parentheses ext4: do not destroy ext4_groupinfo_caches if ext4_mb_init() fails ext4: make local functions static ext4: fix block bitmap validation when bigalloc, ^flex_bg ext4: fix block bitmap initialization under sparse_super2 ext4: find the group descriptors on a 1k-block bigalloc,meta_bg filesystem ext4: avoid unneeded lookup when xattr name is invalid ext4: fix data integrity sync in ordered mode ext4: remove obsoleted check ext4: add a new spinlock i_raw_lock to protect the ext4's raw inode ext4: fix locking for O_APPEND writes ...
2014-06-09 04:03:35 +08:00
* Comments copied from block_write_full_page:
ext4: fix zeroing of page during writeback Tail of a page straddling inode size must be zeroed when being written out due to POSIX requirement that modifications of mmaped page beyond inode size must not be written to the file. ext4_bio_write_page() did this only for blocks fully beyond inode size but didn't properly zero blocks partially beyond inode size. Fix this. The problem has been uncovered by mmap_11-4 test in openposix test suite (part of LTP). Reported-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com> Fixes: 5a0dc7365c240 Fixes: bd2d0210cf22f CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-28 00:48:55 +08:00
*
* The page straddles i_size. It must be zeroed out on each and every
* writepage invocation because it may be mmapped. "A file is mapped
* in multiples of the page size. For a file that is not a multiple of
* the page size, the remaining memory is zeroed when mapped, and
* writes to that region are not written out to the file."
*/
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 20:29:47 +08:00
if (len < PAGE_SIZE)
zero_user_segment(page, len, PAGE_SIZE);
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
/*
* In the first loop we prepare and mark buffers to submit. We have to
* mark all buffers in the page before submitting so that
* end_page_writeback() cannot be called from ext4_bio_end_io() when IO
* on the first buffer finishes and we are still working on submitting
* the second buffer.
*/
bh = head = page_buffers(page);
do {
block_start = bh_offset(bh);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
if (block_start >= len) {
clear_buffer_dirty(bh);
set_buffer_uptodate(bh);
continue;
}
ext4: Make ext4_bio_writepage() handle unprepared buffers So far ext4_bio_writepage() unconditionally cleared dirty bit on all buffers underlying the page. That implicitely assumes we can write all buffers. So far that is true because callers call into ext4_bio_writepage() make sure all buffers in the page are mapped but: a) it's a data corruption bug waiting to happen b) in data=ordered mode when blocksize < pagesize we do need to write pages that may have only some of dirty buffers mapped. So change ext4_bio_writepage() to skip buffers that cannot be written without clearing their dirty bit. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-29 09:53:28 +08:00
if (!buffer_dirty(bh) || buffer_delay(bh) ||
!buffer_mapped(bh) || buffer_unwritten(bh)) {
/* A hole? We can safely clear the dirty bit */
if (!buffer_mapped(bh))
clear_buffer_dirty(bh);
if (io->io_bio)
ext4_io_submit(io);
continue;
}
ext4: cleanup clean_bdev_aliases() calls Now, we have already handle all cases of forgetting buffer in jbd2_journal_forget(), the buffer should not be mapped to blockdevice when reallocating it. So this patch remove all clean_bdev_aliases() and clean_bdev_bh_alias() calls which were invoked by ext4 explicitly. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2019-02-11 12:32:07 +08:00
if (buffer_new(bh))
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
clear_buffer_new(bh);
set_buffer_async_write(bh);
ext4 crypto: fix memory leak in ext4_bio_write_page() There are times when ext4_bio_write_page() is called even though we don't actually need to do any I/O. This happens when ext4_writepage() gets called by the jbd2 commit path when an inode needs to force its pages written out in order to provide data=ordered guarantees --- and a page is backed by an unwritten (e.g., uninitialized) block on disk, or if delayed allocation means the page's backing store hasn't been allocated yet. In that case, we need to skip the call to ext4_encrypt_page(), since in addition to wasting CPU, it leads to a bounce page and an ext4 crypto context getting leaked. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2015-10-03 11:54:58 +08:00
nr_to_submit++;
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
} while ((bh = bh->b_this_page) != head);
bh = head = page_buffers(page);
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
ext4: encrypt only up to last block in ext4_bio_write_page() As an optimization, don't encrypt blocks fully beyond i_size, since those definitely won't need to be written out. Also add a comment. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:52 +08:00
/*
* If any blocks are being written to an encrypted file, encrypt them
* into a bounce page. For simplicity, just encrypt until the last
* block which might be needed. This may cause some unneeded blocks
* (e.g. holes) to be unnecessarily encrypted, but this is rare and
* can't happen in the common case of blocksize == PAGE_SIZE.
*/
ext4: add inline encryption support Wire up ext4 to support inline encryption via the helper functions which fs/crypto/ now provides. This includes: - Adding a mount option 'inlinecrypt' which enables inline encryption on encrypted files where it can be used. - Setting the bio_crypt_ctx on bios that will be submitted to an inline-encrypted file. Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for this part, since ext4 sometimes uses ll_rw_block() on file data. - Not adding logically discontiguous data to bios that will be submitted to an inline-encrypted file. - Not doing filesystem-layer crypto on inline-encrypted files. Co-developed-by: Satya Tangirala <satyat@google.com> Signed-off-by: Satya Tangirala <satyat@google.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/20200702015607.1215430-5-satyat@google.com Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-07-02 09:56:07 +08:00
if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) {
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
gfp_t gfp_flags = GFP_NOFS;
ext4: encrypt only up to last block in ext4_bio_write_page() As an optimization, don't encrypt blocks fully beyond i_size, since those definitely won't need to be written out. Also add a comment. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:52 +08:00
unsigned int enc_bytes = round_up(len, i_blocksize(inode));
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
ext4: fix deadlock allocating crypto bounce page from mempool ext4_writepages() on an encrypted file has to encrypt the data, but it can't modify the pagecache pages in-place, so it encrypts the data into bounce pages and writes those instead. All bounce pages are allocated from a mempool using GFP_NOFS. This is not correct use of a mempool, and it can deadlock. This is because GFP_NOFS includes __GFP_DIRECT_RECLAIM, which enables the "never fail" mode for mempool_alloc() where a failed allocation will fall back to waiting for one of the preallocated elements in the pool. But since this mode is used for all a bio's pages and not just the first, it can deadlock waiting for pages already in the bio to be freed. This deadlock can be reproduced by patching mempool_alloc() to pretend that pool->alloc() always fails (so that it always falls back to the preallocations), and then creating an encrypted file of size > 128 KiB. Fix it by only using GFP_NOFS for the first page in the bio. For subsequent pages just use GFP_NOWAIT, and if any of those fail, just submit the bio and start a new one. This will need to be fixed in f2fs too, but that's less straightforward. Fixes: c9af28fdd449 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20191231181149.47619-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-01 02:11:49 +08:00
/*
* Since bounce page allocation uses a mempool, we can only use
* a waiting mask (i.e. request guaranteed allocation) on the
* first page of the bio. Otherwise it can deadlock.
*/
if (io->io_bio)
gfp_flags = GFP_NOWAIT | __GFP_NOWARN;
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
retry_encrypt:
ext4: encrypt only up to last block in ext4_bio_write_page() As an optimization, don't encrypt blocks fully beyond i_size, since those definitely won't need to be written out. Also add a comment. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:52 +08:00
bounce_page = fscrypt_encrypt_pagecache_blocks(page, enc_bytes,
fscrypt: support encrypting multiple filesystem blocks per page Rename fscrypt_encrypt_page() to fscrypt_encrypt_pagecache_blocks() and redefine its behavior to encrypt all filesystem blocks from the given region of the given page, rather than assuming that the region consists of just one filesystem block. Also remove the 'inode' and 'lblk_num' parameters, since they can be retrieved from the page as it's already assumed to be a pagecache page. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:44 +08:00
0, gfp_flags);
fscrypt: simplify bounce page handling Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-05-21 00:29:39 +08:00
if (IS_ERR(bounce_page)) {
ret = PTR_ERR(bounce_page);
ext4: fix deadlock allocating crypto bounce page from mempool ext4_writepages() on an encrypted file has to encrypt the data, but it can't modify the pagecache pages in-place, so it encrypts the data into bounce pages and writes those instead. All bounce pages are allocated from a mempool using GFP_NOFS. This is not correct use of a mempool, and it can deadlock. This is because GFP_NOFS includes __GFP_DIRECT_RECLAIM, which enables the "never fail" mode for mempool_alloc() where a failed allocation will fall back to waiting for one of the preallocated elements in the pool. But since this mode is used for all a bio's pages and not just the first, it can deadlock waiting for pages already in the bio to be freed. This deadlock can be reproduced by patching mempool_alloc() to pretend that pool->alloc() always fails (so that it always falls back to the preallocations), and then creating an encrypted file of size > 128 KiB. Fix it by only using GFP_NOFS for the first page in the bio. For subsequent pages just use GFP_NOWAIT, and if any of those fail, just submit the bio and start a new one. This will need to be fixed in f2fs too, but that's less straightforward. Fixes: c9af28fdd449 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20191231181149.47619-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-01 02:11:49 +08:00
if (ret == -ENOMEM &&
(io->io_bio || wbc->sync_mode == WB_SYNC_ALL)) {
gfp_flags = GFP_NOFS;
if (io->io_bio)
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
ext4_io_submit(io);
ext4: fix deadlock allocating crypto bounce page from mempool ext4_writepages() on an encrypted file has to encrypt the data, but it can't modify the pagecache pages in-place, so it encrypts the data into bounce pages and writes those instead. All bounce pages are allocated from a mempool using GFP_NOFS. This is not correct use of a mempool, and it can deadlock. This is because GFP_NOFS includes __GFP_DIRECT_RECLAIM, which enables the "never fail" mode for mempool_alloc() where a failed allocation will fall back to waiting for one of the preallocated elements in the pool. But since this mode is used for all a bio's pages and not just the first, it can deadlock waiting for pages already in the bio to be freed. This deadlock can be reproduced by patching mempool_alloc() to pretend that pool->alloc() always fails (so that it always falls back to the preallocations), and then creating an encrypted file of size > 128 KiB. Fix it by only using GFP_NOFS for the first page in the bio. For subsequent pages just use GFP_NOWAIT, and if any of those fail, just submit the bio and start a new one. This will need to be fixed in f2fs too, but that's less straightforward. Fixes: c9af28fdd449 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20191231181149.47619-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-01 02:11:49 +08:00
else
gfp_flags |= __GFP_NOFAIL;
congestion_wait(BLK_RW_ASYNC, HZ/50);
ext4 crypto: don't let data integrity writebacks fail with ENOMEM We don't want the writeback triggered from the journal commit (in data=writeback mode) to cause the journal to abort due to generic_writepages() returning an ENOMEM error. In addition, if fsync() fails with ENOMEM, most applications will probably not do the right thing. So if we are doing a data integrity sync, and ext4_encrypt() returns ENOMEM, we will submit any queued I/O to date, and then retry the allocation using GFP_NOFAIL. Google-Bug-Id: 27641567 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-27 04:14:34 +08:00
goto retry_encrypt;
}
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret);
redirty_page_for_writepage(wbc, page);
do {
clear_buffer_async_write(bh);
bh = bh->b_this_page;
} while (bh != head);
goto unlock;
ext4 crypto: implement the ext4 encryption write path Pulls block_write_begin() into fs/ext4/inode.c because it might need to do a low-level read of the existing data, in which case we need to decrypt it. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12 12:55:10 +08:00
}
}
/* Now submit buffers to write */
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
do {
if (!buffer_async_write(bh))
continue;
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
io_submit_add_bh(io, inode,
bounce_page ? bounce_page : page, bh);
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
nr_submitted++;
ext4: use redirty_page_for_writepage() in ext4_bio_write_page() When we cannot write a page we should use redirty_page_for_writepage() instead of plain set_page_dirty(). That tells writeback code we have problems, redirties only the page (redirtying buffers is not needed), and updates mm accounting of failed page writes. Also move clearing of buffer dirty flag after io_submit_add_bh(). At that moment we are sure buffer will be going to disk. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 22:32:54 +08:00
clear_buffer_dirty(bh);
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
} while ((bh = bh->b_this_page) != head);
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails Similar to [1] [2], bio_alloc with __GFP_DIRECT_RECLAIM flags guarantees bio allocation under some given restrictions, as stated in block/bio.c and fs/direct-io.c So here it's ok to not check for NULL value from bio_alloc(). [1] https://lore.kernel.org/r/20191030035518.65477-1-gaoxiang25@huawei.com [2] https://lore.kernel.org/r/20190830162812.GA10694@infradead.org Cc: Theodore Ts'o <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com> Link: https://lore.kernel.org/r/20191031092315.139267-1-gaoxiang25@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-10-31 17:23:15 +08:00
unlock:
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
unlock_page(page);
ext4: make ext4_bio_write_page() use BH_Async_Write flags So far ext4_bio_write_page() attached all the pages to ext4_io_end structure. This makes that structure pretty heavy (1 KB for pointers + 16 bytes per page attached to the bio). Also later we would like to share ext4_io_end structure among several bios in case IO to a single extent needs to be split among several bios and pointing to pages from ext4_io_end makes this complex. We remove page pointers from ext4_io_end and use pointers from bio itself instead. This isn't as easy when blocksize < pagesize because then we can have several bios in flight for a single page and we have to be careful when to call end_page_writeback(). However this is a known problem already solved by block_write_full_page() / end_buffer_async_write() so we mimic its behavior here. We mark buffers going to disk with BH_Async_Write flag and in ext4_bio_end_io() we check whether there are any buffers with BH_Async_Write flag left. If there are not, we can call end_page_writeback(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-04-12 11:48:32 +08:00
/* Nothing submitted - we have to end page writeback */
if (!nr_submitted)
end_page_writeback(page);
ext4: use bio layer instead of buffer layer in mpage_da_submit_io Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-28 09:30:10 +08:00
return ret;
}