Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  fs: brlock vfsmount_lock
  fs: scale files_lock
  lglock: introduce special lglock and brlock spin locks
  tty: fix fu_list abuse
  fs: cleanup files_lock locking
  fs: remove extra lookup in __lookup_hash
  fs: fs_struct rwlock to spinlock
  apparmor: use task path helpers
  fs: dentry allocation consolidation
  fs: fix do_lookup false negative
  mbcache: Limit the maximum number of cache entries
  hostfs ->follow_link() braino
  hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpy
  remove SWRITE* I/O types
  kill BH_Ordered flag
  vfs: update ctime when changing the file's permission by setfacl
  cramfs: only unlock new inodes
  fix reiserfs_evict_inode end_writeback second call

1 files changed, 9 insertions, 2 deletions

diff --git a/fs/pnode.c b/fs/pnode.c
index 5cc564a83149..8066b8dd748f 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -126,6 +126,9 @@ static int do_make_slave(struct vfsmount *mnt)
         return 0;
 }
 
+/*
+ * vfsmount lock must be held for write
+ */
 void change_mnt_propagation(struct vfsmount *mnt, int type)
 {
         if (type == MS_SHARED) {
@@ -270,12 +273,12 @@ int propagate_mnt(struct vfsmount *dest_mnt, struct dentry *dest_dentry,
                 prev_src_mnt  = child;
         }
 out:
-        spin_lock(&vfsmount_lock);
+        br_write_lock(vfsmount_lock);
         while (!list_empty(&tmp_list)) {
                 child = list_first_entry(&tmp_list, struct vfsmount, mnt_hash);
                 umount_tree(child, 0, &umount_list);
         }
-        spin_unlock(&vfsmount_lock);
+        br_write_unlock(vfsmount_lock);
         release_mounts(&umount_list);
         return ret;
 }
@@ -296,6 +299,8 @@ static inline int do_refcount_check(struct vfsmount *mnt, int count)
  * other mounts its parent propagates to.
  * Check if any of these mounts that **do not have submounts**
  * have more references than 'refcnt'. If so return busy.
+ *
+ * vfsmount lock must be held for read or write
  */
 int propagate_mount_busy(struct vfsmount *mnt, int refcnt)
 {
@@ -353,6 +358,8 @@ static void __propagate_umount(struct vfsmount *mnt)
  * collect all mounts that receive propagation from the mount in @list,
  * and return these additional mounts in the same list.
  * @list: the list of mounts to be unmounted.
+ *
+ * vfsmount lock must be held for write
  */
 int propagate_umount(struct list_head *list)
 {