Commits
Guangyu Sun committed 93fd63c2f00
Btrfs: dir_inode_operations should use btrfs_update_time also Commit 2bc5565286121d2a77ccd728eb3484dff2035b58 (Btrfs: don't update atime on RO subvolumes) ensures that the access time of an inode is not updated when the inode lives in a read-only subvolume. However, if a directory on a read-only subvolume is accessed, the atime is updated. This results in a write operation to a read-only subvolume. I believe that access times should never be updated on read-only subvolumes. To reproduce: # mkfs.btrfs -f /dev/dm-3 (...) # mount /dev/dm-3 /mnt # btrfs subvol create /mnt/sub Create subvolume '/mnt/sub' # mkdir /mnt/sub/dir # echo "abc" > /mnt/sub/dir/file # btrfs subvol snapshot -r /mnt/sub /mnt/rosnap Create a readonly snapshot of '/mnt/sub' in '/mnt/rosnap' # stat /mnt/rosnap/dir File: `/mnt/rosnap/dir' Size: 8 Blocks: 0 IO Block: 4096 directory Device: 16h/22d Inode: 257 Links: 1 Access: (0755/drwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2013-09-11 07:21:49.389157126 -0400 Modify: 2013-09-11 07:22:02.330156079 -0400 Change: 2013-09-11 07:22:02.330156079 -0400 # ls /mnt/rosnap/dir file # stat /mnt/rosnap/dir File: `/mnt/rosnap/dir' Size: 8 Blocks: 0 IO Block: 4096 directory Device: 16h/22d Inode: 257 Links: 1 Access: (0755/drwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2013-09-11 07:22:56.797151670 -0400 Modify: 2013-09-11 07:22:02.330156079 -0400 Change: 2013-09-11 07:22:02.330156079 -0400 Reported-by: Koen De Wit <koen.de.wit@oracle.com> Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>