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

Pull filesystem fixes from Al Viro:
 "Several bugfixes (all of them -stable fodder).

  Alexey's one deals with double mutex_lock() in UFS (apparently, nobody
  has tried to test "ufs: sb mutex merge + mutex_destroy" on something
  like file creation/removal on ufs).  Mine deal with two kinds of
  umount bugs, in umount propagation and in handling of automounted
  submounts, both resulting in bogus transient EBUSY from umount"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ufs: fix deadlocks introduced by sb mutex merge
  fix EBUSY on umount() from MNT_SHRINKABLE
  get rid of propagate_umount() mistakenly treating slaves as busy.

4 files changed, 18 insertions, 14 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index a01c7730e9af..ef42d9bee212 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1217,6 +1217,11 @@ static void namespace_unlock(void)
 	head.first->pprev = &head.first;
 	INIT_HLIST_HEAD(&unmounted);
 
+	/* undo decrements we'd done in umount_tree() */
+	hlist_for_each_entry(mnt, &head, mnt_hash)
+		if (mnt->mnt_ex_mountpoint.mnt)
+			mntget(mnt->mnt_ex_mountpoint.mnt);
+
 	up_write(&namespace_sem);
 
 	synchronize_rcu();
@@ -1253,6 +1258,9 @@ void umount_tree(struct mount *mnt, int how)
 		hlist_add_head(&p->mnt_hash, &tmp_list);
 	}
 
+	hlist_for_each_entry(p, &tmp_list, mnt_hash)
+		list_del_init(&p->mnt_child);
+
 	if (how)
 		propagate_umount(&tmp_list);
 
@@ -1263,9 +1271,9 @@ void umount_tree(struct mount *mnt, int how)
 		p->mnt_ns = NULL;
 		if (how < 2)
 			p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
-		list_del_init(&p->mnt_child);
 		if (mnt_has_parent(p)) {
 			put_mountpoint(p->mnt_mp);
+			mnt_add_count(p->mnt_parent, -1);
 			/* move the reference to mountpoint into ->mnt_ex_mountpoint */
 			p->mnt_ex_mountpoint.dentry = p->mnt_mountpoint;
 			p->mnt_ex_mountpoint.mnt = &p->mnt_parent->mnt;
diff --git a/fs/pnode.c b/fs/pnode.c
index 302bf22c4a30..aae331a5d03b 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -381,6 +381,7 @@ static void __propagate_umount(struct mount *mnt)
 		 * other children
 		 */
 		if (child && list_empty(&child->mnt_mounts)) {
+			list_del_init(&child->mnt_child);
 			hlist_del_init_rcu(&child->mnt_hash);
 			hlist_add_before_rcu(&child->mnt_hash, &mnt->mnt_hash);
 		}
diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c
index 7c580c97990e..be7d42c7d938 100644
--- a/fs/ufs/inode.c
+++ b/fs/ufs/inode.c
@@ -902,9 +902,6 @@ void ufs_evict_inode(struct inode * inode)
 	invalidate_inode_buffers(inode);
 	clear_inode(inode);
 
-	if (want_delete) {
-		lock_ufs(inode->i_sb);
-		ufs_free_inode (inode);
-		unlock_ufs(inode->i_sb);
-	}
+	if (want_delete)
+		ufs_free_inode(inode);
 }
diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c
index 90d74b8f8eba..2df62a73f20c 100644
--- a/fs/ufs/namei.c
+++ b/fs/ufs/namei.c
@@ -126,12 +126,12 @@ static int ufs_symlink (struct inode * dir, struct dentry * dentry,
 	if (l > sb->s_blocksize)
 		goto out_notlocked;
 
-	lock_ufs(dir->i_sb);
 	inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO);
 	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
-		goto out;
+		goto out_notlocked;
 
+	lock_ufs(dir->i_sb);
 	if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {
 		/* slow symlink */
 		inode->i_op = &ufs_symlink_inode_operations;
@@ -181,13 +181,9 @@ static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
 	struct inode * inode;
 	int err;
 
-	lock_ufs(dir->i_sb);
-	inode_inc_link_count(dir);
-
 	inode = ufs_new_inode(dir, S_IFDIR|mode);
-	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
-		goto out_dir;
+		return PTR_ERR(inode);
 
 	inode->i_op = &ufs_dir_inode_operations;
 	inode->i_fop = &ufs_dir_operations;
@@ -195,6 +191,9 @@ static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
 
 	inode_inc_link_count(inode);
 
+	lock_ufs(dir->i_sb);
+	inode_inc_link_count(dir);
+
 	err = ufs_make_empty(inode, dir);
 	if (err)
 		goto out_fail;
@@ -212,7 +211,6 @@ out_fail:
 	inode_dec_link_count(inode);
 	inode_dec_link_count(inode);
 	iput (inode);
-out_dir:
 	inode_dec_link_count(dir);
 	unlock_ufs(dir->i_sb);
 	goto out;