Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6

[sfrench/cifs-2.6.git] / fs / super.c

diff --git a/fs/super.c b/fs/super.c
index 645e5403f2a0da0b4ed97cd6b6499791c732338d..8349ed6b1412aa13e9f23d17fad91e66c9ec1915 100644 (file)
--- a/fs/super.c
+++ b/fs/super.c
@@ -82,7 +82,22 @@ static struct super_block *alloc_super(struct file_system_type *type)
                 * lock ordering than usbfs:
                 */
                lockdep_set_class(&s->s_lock, &type->s_lock_key);
-               down_write(&s->s_umount);
+               /*
+                * sget() can have s_umount recursion.
+                *
+                * When it cannot find a suitable sb, it allocates a new
+                * one (this one), and tries again to find a suitable old
+                * one.
+                *
+                * In case that succeeds, it will acquire the s_umount
+                * lock of the old one. Since these are clearly distrinct
+                * locks, and this object isn't exposed yet, there's no
+                * risk of deadlocks.
+                *
+                * Annotate this by putting this lock in a different
+                * subclass.
+                */
+               down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING);
                s->s_count = S_BIAS;
                atomic_set(&s->s_active, 1);
                mutex_init(&s->s_vfs_rename_mutex);
@@ -301,7 +316,7 @@ void generic_shutdown_super(struct super_block *sb)
                /*
                 * wait for asynchronous fs operations to finish before going further
                 */
-               async_synchronize_full_special(&sb->s_async_list);
+               async_synchronize_full_domain(&sb->s_async_list);
 
                /* bad name - it should be evict_inodes() */
                invalidate_inodes(sb);
@@ -470,7 +485,7 @@ restart:
                sb->s_count++;
                spin_unlock(&sb_lock);
                down_read(&sb->s_umount);
-               async_synchronize_full_special(&sb->s_async_list);
+               async_synchronize_full_domain(&sb->s_async_list);
                if (sb->s_root && (wait || sb->s_dirt))
                        sb->s_op->sync_fs(sb, wait);
                up_read(&sb->s_umount);