mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

btrfs: move and comment read-only check in btrfs_cancel_balance 

Balance cannot be started on a read-only filesystem and will have to
finish/exit before eg. going to read-only via remount.

In case the filesystem is forcibly set to read-only after an error,
balance will finish anyway and if the cancel call is too fast it will
just wait for that to happen.

The last case is when the balance is paused after mount but it's
read-only and cancelling would want to delete the item. The test is
moved after the check if balance is running at all, as it looks more
logical to report "no balance running" instead of "read-only
filesystem".

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2018-03-21 01:45:32 +01:00
parent 3009a62f3b
commit cf7d20f447
1 changed files with 10 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
fs/btrfs/volumes.c
View File

@ -4083,15 +4083,22 @@ int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
{
if (sb_rdonly(fs_info->sb))
return -EROFS;
mutex_lock(&fs_info->balance_mutex);
if (!fs_info->balance_ctl) {
mutex_unlock(&fs_info->balance_mutex);
return -ENOTCONN;
}
/*
* A paused balance with the item stored on disk can be resumed at
* mount time if the mount is read-write. Otherwise it's still paused
* and we must not allow cancelling as it deletes the item.
*/
if (sb_rdonly(fs_info->sb)) {
mutex_unlock(&fs_info->balance_mutex);
return -EROFS;
}
atomic_inc(&fs_info->balance_cancel_req);
/*
* if we are running just wait and return, balance item is