From cbfecb927f429a6fa613d74b998496bd71e4438a Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Thu, 25 Aug 2022 12:06:57 +0200 Subject: fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODE Currently the I_DIRTY_TIME will never get set if the inode already has I_DIRTY_INODE with assumption that it supersedes I_DIRTY_TIME. That's true, however ext4 will only update the on-disk inode in ->dirty_inode(), not on actual writeback. As a result if the inode already has I_DIRTY_INODE state by the time we get to __mark_inode_dirty() only with I_DIRTY_TIME, the time was already filled into on-disk inode and will not get updated until the next I_DIRTY_INODE update, which might never come if we crash or get a power failure. The problem can be reproduced on ext4 by running xfstest generic/622 with -o iversion mount option. Fix it by allowing I_DIRTY_TIME to be set even if the inode already has I_DIRTY_INODE. Also make sure that the case is properly handled in writeback_single_inode() as well. Additionally changes in xfs_fs_dirty_inode() was made to accommodate for I_DIRTY_TIME in flag. Thanks Jan Kara for suggestions on how to make this work properly. Cc: Dave Chinner Cc: Christoph Hellwig Cc: stable@kernel.org Signed-off-by: Lukas Czerner Suggested-by: Jan Kara Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220825100657.44217-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o --- Documentation/filesystems/vfs.rst | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index 6cd6953e175b..b2ef2449aed9 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -274,6 +274,9 @@ or bottom half). This is specifically for the inode itself being marked dirty, not its data. If the update needs to be persisted by fdatasync(), then I_DIRTY_DATASYNC will be set in the flags argument. + I_DIRTY_TIME will be set in the flags in case lazytime is enabled + and struct inode has times updated since the last ->dirty_inode + call. ``write_inode`` this method is called when the VFS needs to write an inode to -- cgit v1.2.3-59-g8ed1b