1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ 2 /* 3 * Copyright (C) 2024 Intel Corporation 4 */ 5 #include <net/gso.h> 6 #include <linux/ieee80211.h> 7 #include <net/ip.h> 8 9 #include "iwl-drv.h" 10 #include "iwl-utils.h" 11 12 #ifdef CONFIG_INET 13 int iwl_tx_tso_segment(struct sk_buff *skb, unsigned int num_subframes, 14 netdev_features_t netdev_flags, 15 struct sk_buff_head *mpdus_skbs) 16 { 17 struct sk_buff *tmp, *next; 18 struct ieee80211_hdr *hdr = (void *)skb->data; 19 char cb[sizeof(skb->cb)]; 20 u16 i = 0; 21 unsigned int tcp_payload_len; 22 unsigned int mss = skb_shinfo(skb)->gso_size; 23 bool ipv4 = (skb->protocol == htons(ETH_P_IP)); 24 bool qos = ieee80211_is_data_qos(hdr->frame_control); 25 u16 ip_base_id = ipv4 ? ntohs(ip_hdr(skb)->id) : 0; 26 27 skb_shinfo(skb)->gso_size = num_subframes * mss; 28 memcpy(cb, skb->cb, sizeof(cb)); 29 30 next = skb_gso_segment(skb, netdev_flags); 31 skb_shinfo(skb)->gso_size = mss; 32 skb_shinfo(skb)->gso_type = ipv4 ? SKB_GSO_TCPV4 : SKB_GSO_TCPV6; 33 34 if (IS_ERR(next) && PTR_ERR(next) == -ENOMEM) 35 return -ENOMEM; 36 37 if (WARN_ONCE(IS_ERR(next), 38 "skb_gso_segment error: %d\n", (int)PTR_ERR(next))) 39 return PTR_ERR(next); 40 41 if (next) 42 consume_skb(skb); 43 44 skb_list_walk_safe(next, tmp, next) { 45 memcpy(tmp->cb, cb, sizeof(tmp->cb)); 46 /* 47 * Compute the length of all the data added for the A-MSDU. 48 * This will be used to compute the length to write in the TX 49 * command. We have: SNAP + IP + TCP for n -1 subframes and 50 * ETH header for n subframes. 51 */ 52 tcp_payload_len = skb_tail_pointer(tmp) - 53 skb_transport_header(tmp) - 54 tcp_hdrlen(tmp) + tmp->data_len; 55 56 if (ipv4) 57 ip_hdr(tmp)->id = htons(ip_base_id + i * num_subframes); 58 59 if (tcp_payload_len > mss) { 60 skb_shinfo(tmp)->gso_size = mss; 61 skb_shinfo(tmp)->gso_type = ipv4 ? SKB_GSO_TCPV4 : 62 SKB_GSO_TCPV6; 63 } else { 64 if (qos) { 65 u8 *qc; 66 67 if (ipv4) 68 ip_send_check(ip_hdr(tmp)); 69 70 qc = ieee80211_get_qos_ctl((void *)tmp->data); 71 *qc &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT; 72 } 73 skb_shinfo(tmp)->gso_size = 0; 74 } 75 76 skb_mark_not_on_list(tmp); 77 __skb_queue_tail(mpdus_skbs, tmp); 78 i++; 79 } 80 81 return 0; 82 } 83 IWL_EXPORT_SYMBOL(iwl_tx_tso_segment); 84 #endif /* CONFIG_INET */ 85