From 67f4b5dc49913abcdb5cc736e73674e2f352f81d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sat, 13 Aug 2022 08:22:25 -0400 Subject: NFS: Fix another fsync() issue after a server reboot Currently, when the writeback code detects a server reboot, it redirties any pages that were not committed to disk, and it sets the flag NFS_CONTEXT_RESEND_WRITES in the nfs_open_context of the file descriptor that dirtied the file. While this allows the file descriptor in question to redrive its own writes, it violates the fsync() requirement that we should be synchronising all writes to disk. While the problem is infrequent, we do see corner cases where an untimely server reboot causes the fsync() call to abandon its attempt to sync data to disk and causing data corruption issues due to missed error conditions or similar. In order to tighted up the client's ability to deal with this situation without introducing livelocks, add a counter that records the number of times pages are redirtied due to a server reboot-like condition, and use that in fsync() to redrive the sync to disk. Fixes: 2197e9b06c22 ("NFS: Fix up fsync() when the server rebooted") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust --- include/linux/nfs_fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/nfs_fs.h') diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index b32ed68e7dc4..f08e581f0161 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -182,6 +182,7 @@ struct nfs_inode { /* Regular file */ struct { atomic_long_t nrequests; + atomic_long_t redirtied_pages; struct nfs_mds_commit_info commit_info; struct mutex commit_mutex; }; -- cgit From 5f6277a0c15e1ea54b6fd3d78c9fff7bfe42556c Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sat, 13 Aug 2022 08:51:45 -0400 Subject: NFS: Cleanup to remove unused flag NFS_CONTEXT_RESEND_WRITES Signed-off-by: Trond Myklebust --- include/linux/nfs_fs.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/nfs_fs.h') diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index f08e581f0161..7931fa472561 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -83,7 +83,6 @@ struct nfs_open_context { fmode_t mode; unsigned long flags; -#define NFS_CONTEXT_RESEND_WRITES (1) #define NFS_CONTEXT_BAD (2) #define NFS_CONTEXT_UNLOCK (3) #define NFS_CONTEXT_FILE_OPEN (4) -- cgit