kernel/linux.git/fs/ext4/fsync.c, branch v6.1.168

block: use an on-stack bio in blkdev_issue_flush

2021-01-27T16:51:48+00:00

There is no point in allocating memory for a synchronous flush. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Chaitanya Kulkarni Acked-by: Damien Le Moal Signed-off-by: Jens Axboe

ext4: use ASSERT() to replace J_ASSERT()

2020-12-03T14:36:57+00:00

There are currently multiple forms of assertion, such as J_ASSERT(). J_ASEERT() is provided for the jbd module, which is a public module. Maybe we should use custom ASSERT() like other file systems, such as xfs, which would be better. Signed-off-by: Chunguang Xu Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/1604764698-4269-1-git-send-email-brookxu@tencent.com Signed-off-by: Theodore Ts'o

ext4: make s_mount_flags modifications atomic

2020-11-07T04:01:05+00:00

Fast commit file system states are recorded in sbi->s_mount_flags. Fast commit expects these bit manipulations to be atomic. This patch adds helpers to make those modifications atomic. Suggested-by: Jan Kara Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20201106035911.1942128-21-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o

ext4: main fast-commit commit path

2020-10-22T03:22:37+00:00

This patch adds main fast commit commit path handlers. The overall patch can be divided into two inter-related parts: (A) Metadata updates tracking This part consists of helper functions to track changes that need to be committed during a commit operation. These updates are maintained by Ext4 in different in-memory queues. Following are the APIs and their short description that are implemented in this patch: - ext4_fc_track_link/unlink/creat() - Track unlink. link and creat operations - ext4_fc_track_range() - Track changed logical block offsets inodes - ext4_fc_track_inode() - Track inodes - ext4_fc_mark_ineligible() - Mark file system fast commit ineligible() - ext4_fc_start_update() / ext4_fc_stop_update() / ext4_fc_start_ineligible() / ext4_fc_stop_ineligible() These functions are useful for co-ordinating inode updates with commits. (B) Main commit Path This part consists of functions to convert updates tracked in in-memory data structures into on-disk commits. Function ext4_fc_commit() is the main entry point to commit path. Reported-by: kernel test robot Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20201015203802.3597742-6-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o

ext4: add trace exit in exception path.

2020-10-18T14:36:59+00:00

Missing trace exit in exception path of ext4_sync_file and ext4_ind_map_blocks. Signed-off-by: Zhang Qilong Link: https://lore.kernel.org/r/20200921124738.23352-1-zhangqilong3@huawei.com Signed-off-by: Theodore Ts'o

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2020-06-05T23:19:28+00:00

Pull ext4 updates from Ted Ts'o: "A lot of bug fixes and cleanups for ext4, including: - Fix performance problems found in dioread_nolock now that it is the default, caused by transaction leaks. - Clean up fiemap handling in ext4 - Clean up and refactor multiple block allocator (mballoc) code - Fix a problem with mballoc with a smaller file systems running out of blocks because they couldn't properly use blocks that had been reserved by inode preallocation. - Fixed a race in ext4_sync_parent() versus rename() - Simplify the error handling in the extent manipulation code - Make sure all metadata I/O errors are felected to ext4_ext_dirty()'s and ext4_make_inode_dirty()'s callers. - Avoid passing an error pointer to brelse in ext4_xattr_set() - Fix race which could result to freeing an inode on the dirty last in data=journal mode. - Fix refcount handling if ext4_iget() fails - Fix a crash in generic/019 caused by a corrupted extent node" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits) ext4: avoid unnecessary transaction starts during writeback ext4: don't block for O_DIRECT if IOCB_NOWAIT is set ext4: remove the access_ok() check in ext4_ioctl_get_es_cache fs: remove the access_ok() check in ioctl_fiemap fs: handle FIEMAP_FLAG_SYNC in fiemap_prep fs: move fiemap range validation into the file systems instances iomap: fix the iomap_fiemap prototype fs: move the fiemap definitions out of fs.h fs: mark __generic_block_fiemap static ext4: remove the call to fiemap_check_flags in ext4_fiemap ext4: split _ext4_fiemap ext4: fix fiemap size checks for bitmap files ext4: fix EXT4_MAX_LOGICAL_BLOCK macro add comment for ext4_dir_entry_2 file_type member jbd2: avoid leaking transaction credits when unreserving handle ext4: drop ext4_journal_free_reserved() ext4: mballoc: use lock for checking free blocks while retrying ext4: mballoc: refactor ext4_mb_good_group() ext4: mballoc: introduce pcpu seqcnt for freeing PA to improve ENOSPC handling ext4: mballoc: refactor ext4_mb_discard_preallocations() ...

ext4: fix race between ext4_sync_parent() and rename()

2020-06-04T03:16:51+00:00

'igrab(d_inode(dentry->d_parent))' without holding dentry->d_lock is broken because without d_lock, d_parent can be concurrently changed due to a rename(). Then if the old directory is immediately deleted, old d_parent->inode can be NULL. That causes a NULL dereference in igrab(). To fix this, use dget_parent() to safely grab a reference to the parent dentry, which pins the inode. This also eliminates the need to use d_find_any_alias() other than for the initial inode, as we no longer throw away the dentry at each step. This is an extremely hard race to hit, but it is possible. Adding a udelay() in between the reads of ->d_parent and its ->d_inode makes it reproducible on a no-journal filesystem using the following program: #include #include int main() { if (fork()) { for (;;) { mkdir("dir1", 0700); int fd = open("dir1/file", O_RDWR|O_CREAT|O_SYNC); write(fd, "X", 1); close(fd); } } else { mkdir("dir2", 0700); for (;;) { rename("dir1/file", "dir2/file"); rmdir("dir1"); } } } Fixes: d59729f4e794 ("ext4: fix races in ext4_sync_parent()") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Link: https://lore.kernel.org/r/20200506183140.541194-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

block: remove the error_sector argument to blkdev_issue_flush

2020-05-22T14:45:46+00:00

The argument isn't used by any caller, and drivers don't fill out bi_sector for flush requests either. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

ext4: update ext4_sync_file() to not use __generic_file_fsync()

2019-11-05T16:31:40+00:00

When the filesystem is created without a journal, we eventually call into __generic_file_fsync() in order to write out all the modified in-core data to the permanent storage device. This function happens to try and obtain an inode_lock() while synchronizing the files buffer and it's associated metadata. Generally, this is fine, however it becomes a problem when there is higher level code that has already obtained an inode_lock() as this leads to a recursive lock situation. This case is especially true when porting across direct I/O to iomap infrastructure as we obtain an inode_lock() early on in the I/O within ext4_dio_write_iter() and hold it until the I/O has been completed. Consequently, to not run into this specific issue, we move away from calling into __generic_file_fsync() and perform the necessary synchronization tasks within ext4_sync_file(). Signed-off-by: Matthew Bobrowski Reviewed-by: Ritesh Harjani Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/3495f35ef67f2021b567e28e6f59222e583689b8.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o

Revert "ext4: use ext4_write_inode() when fsyncing w/o a journal"

2019-02-01T04:41:11+00:00

This reverts commit ad211f3e94b314a910d4af03178a0b52a7d1ee0a. As Jan Kara pointed out, this change was unsafe since it means we lose the call to sync_mapping_buffers() in the nojournal case. The original point of the commit was avoid taking the inode mutex (since it causes a lockdep warning in generic/113); but we need the mutex in order to call sync_mapping_buffers(). The real fix to this problem was discussed here: https://lore.kernel.org/lkml/20181025150540.259281-4-bvanassche@acm.org The proposed patch was to fix a syzbot complaint, but the problem can also demonstrated via "kvm-xfstests -c nojournal generic/113". Multiple solutions were discused in the e-mail thread, but none have landed in the kernel as of this writing. Anyway, commit ad211f3e94b314 is absolutely the wrong way to suppress the lockdep, so revert it. Fixes: ad211f3e94b314a910d4af03178a0b52a7d1ee0a ("ext4: use ext4_write_inode() when fsyncing w/o a journal") Signed-off-by: Theodore Ts'o Reported: Jan Kara