From: J. Bruce Fields <bfields@redhat.com>
Date: Wed, 25 Apr 2012 11:19:52 +0000 (-0400)
Subject: vfs: don't use PARENT/CHILD lock classes for non-directories
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=275555163e3ac09c016c964a10e0f389cf152c4c;p=deliverable%2Flinux.git

vfs: don't use PARENT/CHILD lock classes for non-directories

Reserve I_MUTEX_PARENT and I_MUTEX_CHILD for locking of actual
directories.

(Also I_MUTEX_QUOTA isn't really a meaningful name for this locking
class any more; fixed in a later patch.)

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/inode.c b/fs/inode.c
index ef25afdf3906..51f329b98aa4 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -951,16 +951,16 @@ void lock_two_nondirectories(struct inode *inode1, struct inode *inode2)
 {
 	WARN_ON_ONCE(S_ISDIR(inode1->i_mode));
 	if (inode1 == inode2 || !inode2) {
-		mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
+		mutex_lock(&inode1->i_mutex);
 		return;
 	}
 	WARN_ON_ONCE(S_ISDIR(inode2->i_mode));
 	if (inode1 < inode2) {
-		mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
-		mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
+		mutex_lock(&inode1->i_mutex);
+		mutex_lock_nested(&inode2->i_mutex, I_MUTEX_QUOTA);
 	} else {
-		mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT);
-		mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD);
+		mutex_lock(&inode2->i_mutex);
+		mutex_lock_nested(&inode1->i_mutex, I_MUTEX_QUOTA);
 	}
 }
 EXPORT_SYMBOL(lock_two_nondirectories);