1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* ar-skbuff.c: socket buffer destruction handling 3 * 4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/module.h> 11 #include <linux/net.h> 12 #include <linux/skbuff.h> 13 #include <net/sock.h> 14 #include <net/af_rxrpc.h> 15 #include "ar-internal.h" 16 17 #define is_tx_skb(skb) (rxrpc_skb(skb)->rx_flags & RXRPC_SKB_TX_BUFFER) 18 #define select_skb_count(skb) (is_tx_skb(skb) ? &rxrpc_n_tx_skbs : &rxrpc_n_rx_skbs) 19 20 /* 21 * Note the allocation or reception of a socket buffer. 22 */ 23 void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op) 24 { 25 const void *here = __builtin_return_address(0); 26 int n = atomic_inc_return(select_skb_count(skb)); 27 trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, 28 rxrpc_skb(skb)->rx_flags, 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, enum rxrpc_skb_trace op) 35 { 36 const void *here = __builtin_return_address(0); 37 if (skb) { 38 int n = atomic_read(select_skb_count(skb)); 39 trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, 40 rxrpc_skb(skb)->rx_flags, here); 41 } 42 } 43 44 /* 45 * Note the addition of a ref on a socket buffer. 46 */ 47 void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op) 48 { 49 const void *here = __builtin_return_address(0); 50 int n = atomic_inc_return(select_skb_count(skb)); 51 trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, 52 rxrpc_skb(skb)->rx_flags, here); 53 skb_get(skb); 54 } 55 56 /* 57 * Note the dropping of a ref on a socket buffer by the core. 58 */ 59 void rxrpc_eaten_skb(struct sk_buff *skb, enum rxrpc_skb_trace op) 60 { 61 const void *here = __builtin_return_address(0); 62 int n = atomic_inc_return(&rxrpc_n_rx_skbs); 63 trace_rxrpc_skb(skb, op, 0, n, 0, here); 64 } 65 66 /* 67 * Note the destruction of a socket buffer. 68 */ 69 void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op) 70 { 71 const void *here = __builtin_return_address(0); 72 if (skb) { 73 int n; 74 CHECK_SLAB_OKAY(&skb->users); 75 n = atomic_dec_return(select_skb_count(skb)); 76 trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, 77 rxrpc_skb(skb)->rx_flags, here); 78 kfree_skb(skb); 79 } 80 } 81 82 /* 83 * Clear a queue of socket buffers. 84 */ 85 void rxrpc_purge_queue(struct sk_buff_head *list) 86 { 87 const void *here = __builtin_return_address(0); 88 struct sk_buff *skb; 89 while ((skb = skb_dequeue((list))) != NULL) { 90 int n = atomic_dec_return(select_skb_count(skb)); 91 trace_rxrpc_skb(skb, rxrpc_skb_purged, 92 refcount_read(&skb->users), n, 93 rxrpc_skb(skb)->rx_flags, here); 94 kfree_skb(skb); 95 } 96 } 97