userns: Disassociate user_struct from the user_namespace.

Modify alloc_uid to take a kuid and make the user hash table global.
Stop holding a reference to the user namespace in struct user_struct.

This simplifies the code and makes the per user accounting not
care about which user namespace a uid happens to appear in.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

1 files changed, 0 insertions, 4 deletions

diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index dc2d85a76376..d767508db4f9 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -6,12 +6,8 @@
 #include <linux/sched.h>
 #include <linux/err.h>
 
-#define UIDHASH_BITS    (CONFIG_BASE_SMALL ? 3 : 7)
-#define UIDHASH_SZ      (1 << UIDHASH_BITS)
-
 struct user_namespace {
         struct kref             kref;
-        struct hlist_head       uidhash_table[UIDHASH_SZ];
         struct user_namespace   *parent;
         struct user_struct      *creator;
         struct work_struct      destroyer;