get rid of S_BIAS

[safe/jmp/linux-2.6] / fs / super.c

diff --git a/fs/super.c b/fs/super.c
index d8c8b1d..bc734f8 100644 (file)
--- a/fs/super.c
+++ b/fs/super.c
@@ -93,7 +93,7 @@ static struct super_block *alloc_super(struct file_system_type *type)
                 * subclass.
                 */
                down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING);
-               s->s_count = S_BIAS;
+               s->s_count = 1;
                atomic_set(&s->s_active, 1);
                mutex_init(&s->s_vfs_rename_mutex);
                mutex_init(&s->s_dquot.dqio_mutex);
@@ -189,9 +189,7 @@ void put_super(struct super_block *sb)
 void deactivate_super(struct super_block *s)
 {
        struct file_system_type *fs = s->s_type;
-       if (atomic_dec_and_lock(&s->s_active, &sb_lock)) {
-               s->s_count -= S_BIAS-1;
-               spin_unlock(&sb_lock);
+       if (atomic_dec_and_test(&s->s_active)) {
                vfs_dq_off(s, 0);
                down_write(&s->s_umount);
                fs->kill_sb(s);
@@ -216,9 +214,7 @@ EXPORT_SYMBOL(deactivate_super);
 void deactivate_locked_super(struct super_block *s)
 {
        struct file_system_type *fs = s->s_type;
-       if (atomic_dec_and_lock(&s->s_active, &sb_lock)) {
-               s->s_count -= S_BIAS-1;
-               spin_unlock(&sb_lock);
+       if (atomic_dec_and_test(&s->s_active)) {
                vfs_dq_off(s, 0);
                fs->kill_sb(s);
                put_filesystem(fs);
@@ -243,21 +239,19 @@ EXPORT_SYMBOL(deactivate_locked_super);
  */
 static int grab_super(struct super_block *s) __releases(sb_lock)
 {
+       if (atomic_inc_not_zero(&s->s_active)) {
+               spin_unlock(&sb_lock);
+               down_write(&s->s_umount);
+               return 1;
+       }
+       /* it's going away */
        s->s_count++;
        spin_unlock(&sb_lock);
+       /* usually that'll be enough for it to die... */
        down_write(&s->s_umount);
-       if (s->s_root) {
-               spin_lock(&sb_lock);
-               if (s->s_count > S_BIAS) {
-                       atomic_inc(&s->s_active);
-                       s->s_count--;
-                       spin_unlock(&sb_lock);
-                       return 1;
-               }
-               spin_unlock(&sb_lock);
-       }
        up_write(&s->s_umount);
        put_super(s);
+       /* ... but in case it wasn't, let's at least yield() */
        yield();
        return 0;
 }