ext[234]: move over to 'check_acl' permission model

Don't implement per-filesystem 'extX_permission()' functions that have
to be called for every path component operation, and instead just expose
the actual ACL checking so that the VFS layer can now do it for us.

Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ext2/namei.c

@@ -400,7 +400,7 @@ const struct inode_operations ext2_dir_inode_operations = {
 	.removexattr	= generic_removexattr,
 #endif
 	.setattr	= ext2_setattr,
-	.permission	= ext2_permission,
+	.check_acl	= ext2_check_acl,
 };
 
 const struct inode_operations ext2_special_inode_operations = {
@@ -411,5 +411,5 @@ const struct inode_operations ext2_special_inode_operations = {
 	.removexattr	= generic_removexattr,
 #endif
 	.setattr	= ext2_setattr,
-	.permission	= ext2_permission,
+	.check_acl	= ext2_check_acl,
 };