net: sock: simplify tw proto registration

Introduce the new function tw_prot_init (inspired by
req_prot_init) to simplify "proto_register" function.

tw_prot_cleanup will take care of a partially initialized
timewait_sock_ops.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/sock.c b/net/core/sock.c
index 0ed98f2..cc31b60 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -3440,6 +3440,32 @@ static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
        twsk_prot->twsk_slab = NULL;
 }
 
+static int tw_prot_init(const struct proto *prot)
+{
+       struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
+
+       if (!twsk_prot)
+               return 0;
+
+       twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
+                                             prot->name);
+       if (!twsk_prot->twsk_slab_name)
+               return -ENOMEM;
+
+       twsk_prot->twsk_slab =
+               kmem_cache_create(twsk_prot->twsk_slab_name,
+                                 twsk_prot->twsk_obj_size, 0,
+                                 SLAB_ACCOUNT | prot->slab_flags,
+                                 NULL);
+       if (!twsk_prot->twsk_slab) {
+               pr_crit("%s: Can't create timewait sock SLAB cache!\n",
+                       prot->name);
+               return -ENOMEM;
+       }
+
+       return 0;
+}
+
 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
 {
        if (!rsk_prot)
@@ -3496,22 +3522,8 @@ int proto_register(struct proto *prot, int alloc_slab)
                if (req_prot_init(prot))
                        goto out_free_request_sock_slab;
 
-               if (prot->twsk_prot != NULL) {
-                       prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
-
-                       if (prot->twsk_prot->twsk_slab_name == NULL)
-                               goto out_free_request_sock_slab;
-
-                       prot->twsk_prot->twsk_slab =
-                               kmem_cache_create(prot->twsk_prot->twsk_slab_name,
-                                                 prot->twsk_prot->twsk_obj_size,
-                                                 0,
-                                                 SLAB_ACCOUNT |
-                                                 prot->slab_flags,
-                                                 NULL);
-                       if (prot->twsk_prot->twsk_slab == NULL)
-                               goto out_free_timewait_sock_slab;
-               }
+               if (tw_prot_init(prot))
+                       goto out_free_timewait_sock_slab;
        }
 
        mutex_lock(&proto_list_mutex);