diff options
Diffstat (limited to 'fs/btrfs/locking.h')
| -rw-r--r-- | fs/btrfs/locking.h | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/fs/btrfs/locking.h b/fs/btrfs/locking.h index 31f6d6405c1d..5fabda8f0a80 100644 --- a/fs/btrfs/locking.h +++ b/fs/btrfs/locking.h @@ -16,12 +16,35 @@ #define BTRFS_WRITE_LOCK_BLOCKING 3 #define BTRFS_READ_LOCK_BLOCKING 4 +/* + * We are limited in number of subclasses by MAX_LOCKDEP_SUBCLASSES, which at + * the time of this patch is 8, which is how many we use. Keep this in mind if + * you decide you want to add another subclass. + */ +enum btrfs_lock_nesting { + BTRFS_NESTING_NORMAL, + + /* + * 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 + * definitely using 8, hence this check to keep us from messing up in + * the future. + */ + BTRFS_NESTING_MAX, +}; + +static_assert(BTRFS_NESTING_MAX <= MAX_LOCKDEP_SUBCLASSES, + "too many lock subclasses defined"); + struct btrfs_path; +void __btrfs_tree_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest); void btrfs_tree_lock(struct extent_buffer *eb); void btrfs_tree_unlock(struct extent_buffer *eb); -void __btrfs_tree_read_lock(struct extent_buffer *eb, bool recurse); +void __btrfs_tree_read_lock(struct extent_buffer *eb, enum btrfs_lock_nesting nest, + bool recurse); void btrfs_tree_read_lock(struct extent_buffer *eb); void btrfs_tree_read_unlock(struct extent_buffer *eb); void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb); |