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 #define select_skb_count(op) (op >= rxrpc_skb_tx_cleaned ? &rxrpc_n_tx_skbs : &rxrpc_n_rx_skbs)
22
23 /*
24 * Note the allocation or reception of a socket buffer.
25 */
rxrpc_new_skb(struct sk_buff * skb,enum rxrpc_skb_trace op)26 void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
27 {
28 const void *here = __builtin_return_address(0);
29 int n = atomic_inc_return(select_skb_count(op));
30 trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
31 }
32
33 /*
34 * Note the re-emergence of a socket buffer from a queue or buffer.
35 */
rxrpc_see_skb(struct sk_buff * skb,enum rxrpc_skb_trace op)36 void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
37 {
38 const void *here = __builtin_return_address(0);
39 if (skb) {
40 int n = atomic_read(select_skb_count(op));
41 trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
42 }
43 }
44
45 /*
46 * Note the addition of a ref on a socket buffer.
47 */
rxrpc_get_skb(struct sk_buff * skb,enum rxrpc_skb_trace op)48 void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
49 {
50 const void *here = __builtin_return_address(0);
51 int n = atomic_inc_return(select_skb_count(op));
52 trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
53 skb_get(skb);
54 }
55
56 /*
57 * Note the destruction of a socket buffer.
58 */
rxrpc_free_skb(struct sk_buff * skb,enum rxrpc_skb_trace op)59 void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
60 {
61 const void *here = __builtin_return_address(0);
62 if (skb) {
63 int n;
64 CHECK_SLAB_OKAY(&skb->users);
65 n = atomic_dec_return(select_skb_count(op));
66 trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
67 kfree_skb(skb);
68 }
69 }
70
71 /*
72 * Note the injected loss of a socket buffer.
73 */
rxrpc_lose_skb(struct sk_buff * skb,enum rxrpc_skb_trace op)74 void rxrpc_lose_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
75 {
76 const void *here = __builtin_return_address(0);
77 if (skb) {
78 int n;
79 CHECK_SLAB_OKAY(&skb->users);
80 n = atomic_dec_return(select_skb_count(op));
81 trace_rxrpc_skb(skb, op, atomic_read(&skb->users), n, here);
82 kfree_skb(skb);
83 }
84 }
85
86 /*
87 * Clear a queue of socket buffers.
88 */
rxrpc_purge_queue(struct sk_buff_head * list)89 void rxrpc_purge_queue(struct sk_buff_head *list)
90 {
91 const void *here = __builtin_return_address(0);
92 struct sk_buff *skb;
93 while ((skb = skb_dequeue((list))) != NULL) {
94 int n = atomic_dec_return(select_skb_count(rxrpc_skb_rx_purged));
95 trace_rxrpc_skb(skb, rxrpc_skb_rx_purged,
96 atomic_read(&skb->users), n, here);
97 kfree_skb(skb);
98 }
99 }
100