CRED: Wrap task credential accesses in the UDF filesystem

Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index 082409c..f84bfaa 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -604,7 +604,7 @@
 		goto out;
 
 	iinfo = UDF_I(inode);
-	inode->i_uid = current->fsuid;
+	inode->i_uid = current_fsuid();
 	init_special_inode(inode, mode, rdev);
 	fi = udf_add_entry(dir, dentry, &fibh, &cfi, &err);
 	if (!fi) {