1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* 3 * Copyright (c) 2020 Mellanox Technologies. All rights reserved. 4 */ 5 6 #include <rdma/ib_verbs.h> 7 #include <rdma/ib_cache.h> 8 #include <rdma/lag.h> 9 10 static struct sk_buff *rdma_build_skb(struct net_device *netdev, 11 struct rdma_ah_attr *ah_attr, 12 gfp_t flags) 13 { 14 struct ipv6hdr *ip6h; 15 struct sk_buff *skb; 16 struct ethhdr *eth; 17 struct iphdr *iph; 18 struct udphdr *uh; 19 u8 smac[ETH_ALEN]; 20 bool is_ipv4; 21 int hdr_len; 22 23 is_ipv4 = ipv6_addr_v4mapped((struct in6_addr *)ah_attr->grh.dgid.raw); 24 hdr_len = ETH_HLEN + sizeof(struct udphdr) + LL_RESERVED_SPACE(netdev); 25 hdr_len += is_ipv4 ? sizeof(struct iphdr) : sizeof(struct ipv6hdr); 26 27 skb = alloc_skb(hdr_len, flags); 28 if (!skb) 29 return NULL; 30 31 skb->dev = netdev; 32 skb_reserve(skb, hdr_len); 33 skb_push(skb, sizeof(struct udphdr)); 34 skb_reset_transport_header(skb); 35 uh = udp_hdr(skb); 36 uh->source = 37 htons(rdma_flow_label_to_udp_sport(ah_attr->grh.flow_label)); 38 uh->dest = htons(ROCE_V2_UDP_DPORT); 39 uh->len = htons(sizeof(struct udphdr)); 40 41 if (is_ipv4) { 42 skb_push(skb, sizeof(struct iphdr)); 43 skb_reset_network_header(skb); 44 iph = ip_hdr(skb); 45 iph->frag_off = 0; 46 iph->version = 4; 47 iph->protocol = IPPROTO_UDP; 48 iph->ihl = 0x5; 49 iph->tot_len = htons(sizeof(struct udphdr) + sizeof(struct 50 iphdr)); 51 memcpy(&iph->saddr, ah_attr->grh.sgid_attr->gid.raw + 12, 52 sizeof(struct in_addr)); 53 memcpy(&iph->daddr, ah_attr->grh.dgid.raw + 12, 54 sizeof(struct in_addr)); 55 } else { 56 skb_push(skb, sizeof(struct ipv6hdr)); 57 skb_reset_network_header(skb); 58 ip6h = ipv6_hdr(skb); 59 ip6h->version = 6; 60 ip6h->nexthdr = IPPROTO_UDP; 61 memcpy(&ip6h->flow_lbl, &ah_attr->grh.flow_label, 62 sizeof(*ip6h->flow_lbl)); 63 memcpy(&ip6h->saddr, ah_attr->grh.sgid_attr->gid.raw, 64 sizeof(struct in6_addr)); 65 memcpy(&ip6h->daddr, ah_attr->grh.dgid.raw, 66 sizeof(struct in6_addr)); 67 } 68 69 skb_push(skb, sizeof(struct ethhdr)); 70 skb_reset_mac_header(skb); 71 eth = eth_hdr(skb); 72 skb->protocol = eth->h_proto = htons(is_ipv4 ? ETH_P_IP : ETH_P_IPV6); 73 rdma_read_gid_l2_fields(ah_attr->grh.sgid_attr, NULL, smac); 74 memcpy(eth->h_source, smac, ETH_ALEN); 75 memcpy(eth->h_dest, ah_attr->roce.dmac, ETH_ALEN); 76 77 return skb; 78 } 79 80 static struct net_device *rdma_get_xmit_slave_udp(struct ib_device *device, 81 struct net_device *master, 82 struct rdma_ah_attr *ah_attr, 83 gfp_t flags) 84 { 85 struct net_device *slave; 86 struct sk_buff *skb; 87 88 skb = rdma_build_skb(master, ah_attr, flags); 89 if (!skb) 90 return ERR_PTR(-ENOMEM); 91 92 rcu_read_lock(); 93 slave = netdev_get_xmit_slave(master, skb, 94 !!(device->lag_flags & 95 RDMA_LAG_FLAGS_HASH_ALL_SLAVES)); 96 dev_hold(slave); 97 rcu_read_unlock(); 98 kfree_skb(skb); 99 return slave; 100 } 101 102 void rdma_lag_put_ah_roce_slave(struct net_device *xmit_slave) 103 { 104 if (xmit_slave) 105 dev_put(xmit_slave); 106 } 107 108 struct net_device *rdma_lag_get_ah_roce_slave(struct ib_device *device, 109 struct rdma_ah_attr *ah_attr, 110 gfp_t flags) 111 { 112 struct net_device *slave = NULL; 113 struct net_device *master; 114 115 if (!(ah_attr->type == RDMA_AH_ATTR_TYPE_ROCE && 116 ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP && 117 ah_attr->grh.flow_label)) 118 return NULL; 119 120 rcu_read_lock(); 121 master = rdma_read_gid_attr_ndev_rcu(ah_attr->grh.sgid_attr); 122 if (IS_ERR(master)) { 123 rcu_read_unlock(); 124 return master; 125 } 126 dev_hold(master); 127 rcu_read_unlock(); 128 129 if (!netif_is_bond_master(master)) 130 goto put; 131 132 slave = rdma_get_xmit_slave_udp(device, master, ah_attr, flags); 133 put: 134 dev_put(master); 135 return slave; 136 } 137