diff options
| author | Jan Kara <jack@suse.cz> | 2009-06-04 15:26:49 +0200 |
|---|---|---|
| committer | Joel Becker <joel.becker@oracle.com> | 2009-06-22 14:34:22 -0700 |
| commit | 9a7aa12f3911853a3574d47d567b81a2a5df7208 (patch) | |
| tree | ec3c8efe46b59ed78515ec75302a86054f60d6e5 | |
| parent | df152c241df9e9d2b9a65d37bd02961abe7f591a (diff) | |
| download | op-kernel-dev-9a7aa12f3911853a3574d47d567b81a2a5df7208.zip op-kernel-dev-9a7aa12f3911853a3574d47d567b81a2a5df7208.tar.gz | |
vfs: Set special lockdep map for dirs only if not set by fs
Some filesystems need to set lockdep map for i_mutex differently for
different directories. For example OCFS2 has system directories (for
orphan inode tracking and for gathering all system files like journal
or quota files into a single place) which have different locking
locking rules than standard directories. For a filesystem setting
lockdep map is naturaly done when the inode is read but we have to
modify unlock_new_inode() not to overwrite the lockdep map the filesystem
has set.
Acked-by: peterz@infradead.org
CC: mingo@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
| -rw-r--r-- | fs/inode.c | 17 | ||||
| -rw-r--r-- | include/linux/lockdep.h | 15 |
2 files changed, 26 insertions, 6 deletions
@@ -665,12 +665,17 @@ void unlock_new_inode(struct inode *inode) if (inode->i_mode & S_IFDIR) { struct file_system_type *type = inode->i_sb->s_type; - /* - * ensure nobody is actually holding i_mutex - */ - mutex_destroy(&inode->i_mutex); - mutex_init(&inode->i_mutex); - lockdep_set_class(&inode->i_mutex, &type->i_mutex_dir_key); + /* Set new key only if filesystem hasn't already changed it */ + if (!lockdep_match_class(&inode->i_mutex, + &type->i_mutex_key)) { + /* + * ensure nobody is actually holding i_mutex + */ + mutex_destroy(&inode->i_mutex); + mutex_init(&inode->i_mutex); + lockdep_set_class(&inode->i_mutex, + &type->i_mutex_dir_key); + } } #endif /* diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index da5a5a1..b25d1b5 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -258,6 +258,16 @@ extern void lockdep_init_map(struct lockdep_map *lock, const char *name, #define lockdep_set_subclass(lock, sub) \ lockdep_init_map(&(lock)->dep_map, #lock, \ (lock)->dep_map.key, sub) +/* + * Compare locking classes + */ +#define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key) + +static inline int lockdep_match_key(struct lockdep_map *lock, + struct lock_class_key *key) +{ + return lock->key == key; +} /* * Acquire a lock. @@ -326,6 +336,11 @@ static inline void lockdep_on(void) #define lockdep_set_class_and_subclass(lock, key, sub) \ do { (void)(key); } while (0) #define lockdep_set_subclass(lock, sub) do { } while (0) +/* + * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP + * case since the result is not well defined and the caller should rather + * #ifdef the call himself. + */ # define INIT_LOCKDEP # define lockdep_reset() do { debug_locks = 1; } while (0) |
