mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-02 15:18:19 +00:00
Code Issues Releases Wiki Activity

btrfs: clear oneshot options on mount and remount

Browse source 
Some options only apply during mount time and are cleared at the end
of mount. For now, the example is USEBACKUPROOT, but CLEAR_CACHE also
fits the bill, and this is a preparation patch for also clearing that
option.

One subtlety is that the current code only resets USEBACKUPROOT on rw
mounts, but the option is meaningfully "consumed" by a ro mount, so it
feels appropriate to clear in that case as well. A subsequent read-write
remount would not go through open_ctree, which is the only place that
checks the option, so the change should be benign.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Boris Burkov 2020-11-18 15:06:20 -08:00 committed by David Sterba
parent 5011139a47
commit 8cd2908846
3 changed files with 15 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
fs/btrfs/disk-io.c
View file

@ -2870,6 +2870,16 @@ static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
return 0;
}
/*
* Some options only have meaning at mount time and shouldn't persist across
* remounts, or be displayed. Clear these at the end of mount and remount
* code paths.
*/
void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info)
{
btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT);
}
/*
* Mounting logic specific to read-write file systems. Shared by open_ctree
* and btrfs_remount when remounting from read-only to read-write.
@ -3359,7 +3369,7 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
}
if (sb_rdonly(sb))
return 0;
goto clear_oneshot;
if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
@ -3402,6 +3412,8 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
}
set_bit(BTRFS_FS_OPEN, &fs_info->flags);
clear_oneshot:
btrfs_clear_oneshot_options(fs_info);
return 0;
fail_qgroup:

1
fs/btrfs/disk-io.h
View file

@ -50,6 +50,7 @@ struct extent_buffer *btrfs_find_create_tree_block(
u64 bytenr, u64 owner_root,
int level);
void btrfs_clean_tree_block(struct extent_buffer *buf);
void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
int __cold open_ctree(struct super_block *sb,
struct btrfs_fs_devices *fs_devices,

1
fs/btrfs/super.c
View file

@ -1999,6 +1999,7 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data)
wake_up_process(fs_info->transaction_kthread);
btrfs_remount_cleanup(fs_info, old_opts);
btrfs_clear_oneshot_options(fs_info);
clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state);
return 0;