devcgroup_inode_permission: take "is it a device node" checks to inlined wrapper

inode_permission() calls devcgroup_inode_permission() and almost all such
calls are _not_ for device nodes; let's at least keep the common path
straight...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 9 insertions, 1 deletions

diff --git a/include/linux/device_cgroup.h b/include/linux/device_cgroup.h
index 0b0d9c39ed67..7aad1f440867 100644
--- a/include/linux/device_cgroup.h
+++ b/include/linux/device_cgroup.h
@@ -2,8 +2,16 @@
 #include <linux/fs.h>
 
 #ifdef CONFIG_CGROUP_DEVICE
-extern int devcgroup_inode_permission(struct inode *inode, int mask);
+extern int __devcgroup_inode_permission(struct inode *inode, int mask);
 extern int devcgroup_inode_mknod(int mode, dev_t dev);
+static inline int devcgroup_inode_permission(struct inode *inode, int mask)
+{
+        if (likely(!inode->i_rdev))
+                return 0;
+        if (!S_ISBLK(inode->i_mode) && !S_ISCHR(inode->i_mode))
+                return 0;
+        return __devcgroup_inode_permission(inode, mask);
+}
 #else
 static inline int devcgroup_inode_permission(struct inode *inode, int mask)
 { return 0; }