[PATCH] remove lock_kernel() from inode_setattr's

vmtruncate() does not need lock_kernel().  And lock_kernel() is not taken by
other vmtruncate() callers.

fs/attr.c

@@ -68,17 +68,11 @@ int inode_setattr(struct inode * inode, struct iattr * attr)
 	int error = 0;
 
 	if (ia_valid & ATTR_SIZE) {
-		if (attr->ia_size == inode->i_size) {
-			if (ia_valid == ATTR_SIZE)
-				goto out;	/* we can skip lock_kernel() */
-		} else {
-			lock_kernel();
+		if (attr->ia_size != inode->i_size)
 			error = vmtruncate(inode, attr->ia_size);
-			unlock_kernel();
-			if (error)
+		if (error || (ia_valid == ATTR_SIZE))
 			goto out;
 	}
-	}
 
 	lock_kernel();
 	if (ia_valid & ATTR_UID)