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/gfs2/inode.c b/fs/gfs2/inode.c
index 0fb51a9..900cf98 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1846,7 +1846,7 @@
 	.listxattr = gfs2_listxattr,
 	.removexattr = gfs2_removexattr,
 	.fiemap = gfs2_fiemap,
-	.check_acl = gfs2_check_acl,
+	.get_acl = gfs2_get_acl,
 };
 
 const struct inode_operations gfs2_dir_iops = {
@@ -1867,7 +1867,7 @@
 	.listxattr = gfs2_listxattr,
 	.removexattr = gfs2_removexattr,
 	.fiemap = gfs2_fiemap,
-	.check_acl = gfs2_check_acl,
+	.get_acl = gfs2_get_acl,
 };
 
 const struct inode_operations gfs2_symlink_iops = {
@@ -1882,6 +1882,6 @@
 	.listxattr = gfs2_listxattr,
 	.removexattr = gfs2_removexattr,
 	.fiemap = gfs2_fiemap,
-	.check_acl = gfs2_check_acl,
+	.get_acl = gfs2_get_acl,
 };