[PATCH] mutex subsystem, semaphore to mutex: VFS, sb->s_lock

This patch converts the superblock-lock semaphore to a mutex, affecting
lock_super()/unlock_super(). Tested on ext3 and XFS.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 6 insertions, 6 deletions

diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index c3dbebdb989..56bf7658601 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2150,7 +2150,7 @@ int ext3_force_commit(struct super_block *sb)
 
 static void ext3_write_super (struct super_block * sb)
 {
-        if (down_trylock(&sb->s_lock) == 0)
+        if (mutex_trylock(&sb->s_lock) != 0)
                 BUG();
         sb->s_dirt = 0;
 }
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 48bf7f0ce54..364d64bd5f1 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -169,7 +169,7 @@ static match_table_t tokens = {
  */
 static void ocfs2_write_super(struct super_block *sb)
 {
-        if (down_trylock(&sb->s_lock) == 0)
+        if (mutex_trylock(&sb->s_lock) != 0)
                 BUG();
         sb->s_dirt = 0;
 }
diff --git a/fs/super.c b/fs/super.c
index 0a30e51692c..c177b92419c 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -72,7 +72,7 @@ static struct super_block *alloc_super(void)
                 INIT_HLIST_HEAD(&s->s_anon);
                 INIT_LIST_HEAD(&s->s_inodes);
                 init_rwsem(&s->s_umount);
-                sema_init(&s->s_lock, 1);
+                mutex_init(&s->s_lock);
                 down_write(&s->s_umount);
                 s->s_count = S_BIAS;
                 atomic_set(&s->s_active, 1);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 01654b218e4..92ae3e2067b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -821,7 +821,7 @@ struct super_block {
         unsigned long           s_magic;
         struct dentry           *s_root;
         struct rw_semaphore     s_umount;
-        struct semaphore        s_lock;
+        struct mutex            s_lock;
         int                     s_count;
         int                     s_syncing;
         int                     s_need_sync_fs;
@@ -893,13 +893,13 @@ static inline int has_fs_excl(void)
 static inline void lock_super(struct super_block * sb)
 {
         get_fs_excl();
-        down(&sb->s_lock);
+        mutex_lock(&sb->s_lock);
 }
 
 static inline void unlock_super(struct super_block * sb)
 {
         put_fs_excl();
-        up(&sb->s_lock);
+        mutex_unlock(&sb->s_lock);
 }
 
 /*