From: "Darrick J. Wong" djwong@kernel.org
stable inclusion from linux-4.19.231 commit d5c33270b8b2c274eb8df7b92d166166102528c6
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[ Upstream commit 2719c7160dcfaae1f73a1c0c210ad3281c19022e ]
If we fail to synchronize the filesystem while preparing to freeze the fs, abort the freeze.
Signed-off-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Jan Kara jack@suse.cz Reviewed-by: Christoph Hellwig hch@lst.de Acked-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yongqiang Liu liuyongqiang13@huawei.com Signed-off-by: Laibin Qiu qiulaibin@huawei.com --- fs/super.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/fs/super.c b/fs/super.c index 9fb4553c46e6..8dc26e23f1a3 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1404,11 +1404,9 @@ static void lockdep_sb_freeze_acquire(struct super_block *sb) percpu_rwsem_acquire(sb->s_writers.rw_sem + level, 0, _THIS_IP_); }
-static void sb_freeze_unlock(struct super_block *sb) +static void sb_freeze_unlock(struct super_block *sb, int level) { - int level; - - for (level = SB_FREEZE_LEVELS - 1; level >= 0; level--) + for (level--; level >= 0; level--) percpu_up_write(sb->s_writers.rw_sem + level); }
@@ -1479,7 +1477,14 @@ int freeze_super(struct super_block *sb) sb_wait_write(sb, SB_FREEZE_PAGEFAULT);
/* All writers are done so after syncing there won't be dirty data */ - sync_filesystem(sb); + ret = sync_filesystem(sb); + if (ret) { + sb->s_writers.frozen = SB_UNFROZEN; + sb_freeze_unlock(sb, SB_FREEZE_PAGEFAULT); + wake_up(&sb->s_writers.wait_unfrozen); + deactivate_locked_super(sb); + return ret; + }
/* Now wait for internal filesystem counter */ sb->s_writers.frozen = SB_FREEZE_FS; @@ -1491,7 +1496,7 @@ int freeze_super(struct super_block *sb) printk(KERN_ERR "VFS:Filesystem freeze failed\n"); sb->s_writers.frozen = SB_UNFROZEN; - sb_freeze_unlock(sb); + sb_freeze_unlock(sb, SB_FREEZE_FS); wake_up(&sb->s_writers.wait_unfrozen); deactivate_locked_super(sb); return ret; @@ -1542,7 +1547,7 @@ static int thaw_super_locked(struct super_block *sb) }
sb->s_writers.frozen = SB_UNFROZEN; - sb_freeze_unlock(sb); + sb_freeze_unlock(sb, SB_FREEZE_FS); out: wake_up(&sb->s_writers.wait_unfrozen); deactivate_locked_super(sb);