net/rxrpc/skbuff.c

   1 /* ar-skbuff.c: socket buffer destruction handling
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/net.h>
  16 #include <linux/skbuff.h>
  17 #include <net/sock.h>
  18 #include <net/af_rxrpc.h>
  19 #include "ar-internal.h"
  20
  21 /*
  22  * Note the existence of a new-to-us socket buffer (allocated or dequeued).
  23  */
  24 void rxrpc_new_skb(struct sk_buff *skb)
  25 {
  26         const void *here = __builtin_return_address(0);
  27         int n = atomic_inc_return(&rxrpc_n_skbs);
  28         trace_rxrpc_skb(skb, 0, atomic_read(&skb->users), n, here);
  29 }
  30
  31 /*
  32  * Note the re-emergence of a socket buffer from a queue or buffer.
  33  */
  34 void rxrpc_see_skb(struct sk_buff *skb)
  35 {
  36         const void *here = __builtin_return_address(0);
  37         if (skb) {
  38                 int n = atomic_read(&rxrpc_n_skbs);
  39                 trace_rxrpc_skb(skb, 1, atomic_read(&skb->users), n, here);
  40         }
  41 }
  42
  43 /*
  44  * Note the addition of a ref on a socket buffer.
  45  */
  46 void rxrpc_get_skb(struct sk_buff *skb)
  47 {
  48         const void *here = __builtin_return_address(0);
  49         int n = atomic_inc_return(&rxrpc_n_skbs);
  50         trace_rxrpc_skb(skb, 2, atomic_read(&skb->users), n, here);
  51         skb_get(skb);
  52 }
  53
  54 /*
  55  * Note the destruction of a socket buffer.
  56  */
  57 void rxrpc_free_skb(struct sk_buff *skb)
  58 {
  59         const void *here = __builtin_return_address(0);
  60         if (skb) {
  61                 int n;
  62                 CHECK_SLAB_OKAY(&skb->users);
  63                 n = atomic_dec_return(&rxrpc_n_skbs);
  64                 trace_rxrpc_skb(skb, 3, atomic_read(&skb->users), n, here);
  65                 kfree_skb(skb);
  66         }
  67 }
  68
  69 /*
  70  * Clear a queue of socket buffers.
  71  */
  72 void rxrpc_purge_queue(struct sk_buff_head *list)
  73 {
  74         const void *here = __builtin_return_address(0);
  75         struct sk_buff *skb;
  76         while ((skb = skb_dequeue((list))) != NULL) {
  77                 int n = atomic_dec_return(&rxrpc_n_skbs);
  78                 trace_rxrpc_skb(skb, 4, atomic_read(&skb->users), n, here);
  79                 kfree_skb(skb);
  80         }
  81 }