diff options
| author | Josef Bacik <josef@toxicpanda.com> | 2020-08-20 11:46:05 -0400 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-10-07 12:12:16 +0200 |
| commit | bf59a5a21604ef79da9105bef1bae817fd053e75 (patch) | |
| tree | c77e328755674e909fede6da8bca28748b6584b1 /fs/btrfs/locking.h | |
| parent | bf77467a93bdf11d815f5c5f25206a0d058da8de (diff) | |
btrfs: introduce BTRFS_NESTING_LEFT/RIGHT_COW
For similar reasons as BTRFS_NESTING_COW, we need
BTRFS_NESTING_LEFT/RIGHT_COW. The pattern is this
lock leaf -> BTRFS_NESTING_NORMAL
cow leaf -> BTRFS_NESTING_COW
split leaf
lock left -> BTRFS_NESTING_LEFT
cow left -> BTRFS_NESTING_LEFT_COW
We need this in order to indicate to lockdep that these locks are
discrete and are being taken in a safe order.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/locking.h')
| -rw-r--r-- | fs/btrfs/locking.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/btrfs/locking.h b/fs/btrfs/locking.h index 5844bc1c8410..16563bc486c7 100644 --- a/fs/btrfs/locking.h +++ b/fs/btrfs/locking.h @@ -45,6 +45,14 @@ enum btrfs_lock_nesting { BTRFS_NESTING_RIGHT, /* + * When splitting we will be holding a lock on the left/right node when + * we need to cow that node, thus we need a new set of subclasses for + * these two operations. + */ + BTRFS_NESTING_LEFT_COW, + BTRFS_NESTING_RIGHT_COW, + + /* * We are limited to MAX_LOCKDEP_SUBLCLASSES number of subclasses, so * add this in here and add a static_assert to keep us from going over * the limit. As of this writing we're limited to 8, and we're |