From: Christoph Hellwig hch@lst.de
mainline-inclusion from mainline-v5.11-rc4 commit ae29e4220fd3047b5442e7e8db8027d7745093f5 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4KIAO CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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If the inode is not pinned by the time fsync is called we don't need the ilock to protect against concurrent clearing of ili_fsync_fields as the inode won't need a log flush or clearing of these fields. Not taking the iolock allows for full concurrency of fsync and thus O_DSYNC completions with io_uring/aio write submissions.
Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Dave Chinner dchinner@redhat.com Signed-off-by: Lihong Kou koulihong@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- fs/xfs/xfs_file.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 407d884bf7e0..2fb8cf556f8d 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -200,7 +200,14 @@ xfs_file_fsync( else if (mp->m_logdev_targp != mp->m_ddev_targp) xfs_blkdev_issue_flush(mp->m_ddev_targp);
- error = xfs_fsync_flush_log(ip, datasync, &log_flushed); + /* + * Any inode that has dirty modifications in the log is pinned. The + * racy check here for a pinned inode while not catch modifications + * that happen concurrently to the fsync call, but fsync semantics + * only require to sync previously completed I/O. + */ + if (xfs_ipincount(ip)) + error = xfs_fsync_flush_log(ip, datasync, &log_flushed);
/* * If we only have a single device, and the log force about was