1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2023 Intel Corporation 3 */ 4 #ifndef _GRO_TCP_H_ 5 #define _GRO_TCP_H_ 6 7 #define INVALID_ARRAY_INDEX 0xffffffffUL 8 9 #include <rte_tcp.h> 10 11 /* 12 * The max length of a IPv4 packet, which includes the length of the L3 13 * header, the L4 header and the data payload. 14 */ 15 #define MAX_IP_PKT_LENGTH UINT16_MAX 16 17 /* The maximum TCP header length */ 18 #define MAX_TCP_HLEN 60 19 #define INVALID_TCP_HDRLEN(len) \ 20 (((len) < sizeof(struct rte_tcp_hdr)) || ((len) > MAX_TCP_HLEN)) 21 22 #define VALID_GRO_TCP_FLAGS (RTE_TCP_ACK_FLAG | RTE_TCP_PSH_FLAG | RTE_TCP_FIN_FLAG) 23 24 struct cmn_tcp_key { 25 struct rte_ether_addr eth_saddr; 26 struct rte_ether_addr eth_daddr; 27 uint32_t recv_ack; 28 uint16_t src_port; 29 uint16_t dst_port; 30 }; 31 32 #define ASSIGN_COMMON_TCP_KEY(k1, k2) \ 33 do {\ 34 rte_ether_addr_copy(&(k1->eth_saddr), &(k2->eth_saddr)); \ 35 rte_ether_addr_copy(&(k1->eth_daddr), &(k2->eth_daddr)); \ 36 k2->recv_ack = k1->recv_ack; \ 37 k2->src_port = k1->src_port; \ 38 k2->dst_port = k1->dst_port; \ 39 } while (0) 40 41 struct gro_tcp_item { 42 /* 43 * The first MBUF segment of the packet. If the value 44 * is NULL, it means the item is empty. 45 */ 46 struct rte_mbuf *firstseg; 47 /* The last MBUF segment of the packet */ 48 struct rte_mbuf *lastseg; 49 /* 50 * The time when the first packet is inserted into the table. 51 * This value won't be updated, even if the packet is merged 52 * with other packets. 53 */ 54 uint64_t start_time; 55 /* 56 * next_pkt_idx is used to chain the packets that 57 * are in the same flow but can't be merged together 58 * (e.g. caused by packet reordering). 59 */ 60 uint32_t next_pkt_idx; 61 /* TCP sequence number of the packet */ 62 uint32_t sent_seq; 63 union { 64 /* IPv4 ID of the packet */ 65 uint16_t ip_id; 66 /* Unused field for IPv6 */ 67 uint16_t unused; 68 } l3; 69 /* the number of merged packets */ 70 uint16_t nb_merged; 71 /* Indicate if IPv4 ID can be ignored */ 72 uint8_t is_atomic; 73 }; 74 75 /* 76 * Merge two TCP packets without updating checksums. 77 * If cmp is larger than 0, append the new packet to the 78 * original packet. Otherwise, pre-pend the new packet to 79 * the original packet. 80 */ 81 static inline int 82 merge_two_tcp_packets(struct gro_tcp_item *item, 83 struct rte_mbuf *pkt, 84 int cmp, 85 uint32_t sent_seq, 86 uint8_t tcp_flags, 87 uint16_t ip_id, 88 uint16_t l2_offset) 89 { 90 struct rte_mbuf *pkt_head, *pkt_tail, *lastseg; 91 uint16_t hdr_len, l2_len; 92 struct rte_tcp_hdr *tcp_hdr; 93 94 if (cmp > 0) { 95 pkt_head = item->firstseg; 96 pkt_tail = pkt; 97 } else { 98 pkt_head = pkt; 99 pkt_tail = item->firstseg; 100 } 101 102 /* check if the IPv4 packet length is greater than the max value */ 103 hdr_len = l2_offset + pkt_head->l2_len + pkt_head->l3_len + 104 pkt_head->l4_len; 105 l2_len = l2_offset > 0 ? pkt_head->outer_l2_len : pkt_head->l2_len; 106 if (unlikely(pkt_head->pkt_len - l2_len + pkt_tail->pkt_len - 107 hdr_len > MAX_IP_PKT_LENGTH)) 108 return 0; 109 110 if (unlikely(pkt_head->nb_segs >= 20)) 111 return 0; 112 113 /* remove the packet header for the tail packet */ 114 rte_pktmbuf_adj(pkt_tail, hdr_len); 115 116 /* chain two packets together */ 117 if (cmp > 0) { 118 item->lastseg->next = pkt; 119 item->lastseg = rte_pktmbuf_lastseg(pkt); 120 /* update IP ID to the larger value */ 121 item->l3.ip_id = ip_id; 122 } else { 123 lastseg = rte_pktmbuf_lastseg(pkt); 124 lastseg->next = item->firstseg; 125 item->firstseg = pkt; 126 /* update sent_seq to the smaller value */ 127 item->sent_seq = sent_seq; 128 item->l3.ip_id = ip_id; 129 } 130 item->nb_merged++; 131 132 /* update MBUF metadata for the merged packet */ 133 pkt_head->nb_segs += pkt_tail->nb_segs; 134 pkt_head->pkt_len += pkt_tail->pkt_len; 135 if (tcp_flags != RTE_TCP_ACK_FLAG) { 136 tcp_hdr = rte_pktmbuf_mtod_offset(pkt, struct rte_tcp_hdr *, 137 l2_offset + pkt_head->l2_len + pkt_head->l3_len); 138 tcp_hdr->tcp_flags |= tcp_flags; 139 } 140 141 return 1; 142 } 143 144 /* 145 * Check if two TCP packets are neighbors. 146 */ 147 static inline int 148 check_seq_option(struct gro_tcp_item *item, 149 struct rte_tcp_hdr *tcph, 150 uint32_t sent_seq, 151 uint16_t ip_id, 152 uint16_t tcp_hl, 153 uint16_t tcp_dl, 154 uint16_t l2_offset, 155 uint8_t is_atomic) 156 { 157 struct rte_mbuf *pkt_orig = item->firstseg; 158 char *iph_orig; 159 struct rte_tcp_hdr *tcph_orig; 160 uint16_t len, tcp_hl_orig; 161 162 iph_orig = rte_pktmbuf_mtod_offset(pkt_orig, char *, 163 l2_offset + pkt_orig->l2_len); 164 tcph_orig = (struct rte_tcp_hdr *)(iph_orig + pkt_orig->l3_len); 165 tcp_hl_orig = pkt_orig->l4_len; 166 167 /* Check if TCP option fields equal */ 168 len = RTE_MAX(tcp_hl, tcp_hl_orig) - sizeof(struct rte_tcp_hdr); 169 if ((tcp_hl != tcp_hl_orig) || ((len > 0) && 170 (memcmp(tcph + 1, tcph_orig + 1, 171 len) != 0))) 172 return 0; 173 174 /* Don't merge packets whose DF bits are different */ 175 if (unlikely(item->is_atomic ^ is_atomic)) 176 return 0; 177 178 /* check if the two packets are neighbors */ 179 len = pkt_orig->pkt_len - l2_offset - pkt_orig->l2_len - 180 pkt_orig->l3_len - tcp_hl_orig; 181 if ((sent_seq == item->sent_seq + len) && (is_atomic || 182 (ip_id == item->l3.ip_id + 1))) 183 /* append the new packet */ 184 return 1; 185 else if ((sent_seq + tcp_dl == item->sent_seq) && (is_atomic || 186 (ip_id + item->nb_merged == item->l3.ip_id))) 187 /* pre-pend the new packet */ 188 return -1; 189 190 return 0; 191 } 192 193 static inline int 194 is_same_common_tcp_key(struct cmn_tcp_key *k1, struct cmn_tcp_key *k2) 195 { 196 return (!memcmp(k1, k2, sizeof(struct cmn_tcp_key))); 197 } 198 199 #endif 200