diff options
Diffstat (limited to 'fs/super.c')
| -rw-r--r-- | fs/super.c | 28 |
1 files changed, 11 insertions, 17 deletions
diff --git a/fs/super.c b/fs/super.c index d8c8b1d2d010..bc734f8b3e18 100644 --- 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; } |