CRED: Wrap task credential accesses in the HFS 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>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/fs/hfs/super.c b/fs/hfs/super.c
index 3c7c763..c8b5acf 100644
--- a/fs/hfs/super.c
+++ b/fs/hfs/super.c
@@ -210,8 +210,8 @@
 	int tmp, token;
 
 	/* initialize the sb with defaults */
-	hsb->s_uid = current->uid;
-	hsb->s_gid = current->gid;
+	hsb->s_uid = current_uid();
+	hsb->s_gid = current_gid();
 	hsb->s_file_umask = 0133;
 	hsb->s_dir_umask = 0022;
 	hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f);	/* == '????' */