fs: take the ACL checks to common code

Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 803f59f..9d808d0 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -872,7 +872,7 @@
 	.getxattr = generic_getxattr,
 	.removexattr = generic_removexattr,
 	.listxattr = v9fs_listxattr,
-	.check_acl = v9fs_check_acl,
+	.get_acl = v9fs_iop_get_acl,
 };
 
 const struct inode_operations v9fs_file_inode_operations_dotl = {
@@ -882,7 +882,7 @@
 	.getxattr = generic_getxattr,
 	.removexattr = generic_removexattr,
 	.listxattr = v9fs_listxattr,
-	.check_acl = v9fs_check_acl,
+	.get_acl = v9fs_iop_get_acl,
 };
 
 const struct inode_operations v9fs_symlink_inode_operations_dotl = {