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
rdma_build_skb(struct net_device * netdev,struct rdma_ah_attr * ah_attr,gfp_t flags)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
rdma_get_xmit_slave_udp(struct ib_device * device,struct net_device * master,struct rdma_ah_attr * ah_attr,gfp_t flags)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
rdma_lag_put_ah_roce_slave(struct net_device * xmit_slave)102 void rdma_lag_put_ah_roce_slave(struct net_device *xmit_slave)
103 {
104 dev_put(xmit_slave);
105 }
106
rdma_lag_get_ah_roce_slave(struct ib_device * device,struct rdma_ah_attr * ah_attr,gfp_t flags)107 struct net_device *rdma_lag_get_ah_roce_slave(struct ib_device *device,
108 struct rdma_ah_attr *ah_attr,
109 gfp_t flags)
110 {
111 struct net_device *slave = NULL;
112 struct net_device *master;
113
114 if (!(ah_attr->type == RDMA_AH_ATTR_TYPE_ROCE &&
115 ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
116 ah_attr->grh.flow_label))
117 return NULL;
118
119 rcu_read_lock();
120 master = rdma_read_gid_attr_ndev_rcu(ah_attr->grh.sgid_attr);
121 if (IS_ERR(master)) {
122 rcu_read_unlock();
123 return master;
124 }
125 dev_hold(master);
126 rcu_read_unlock();
127
128 if (!netif_is_bond_master(master))
129 goto put;
130
131 slave = rdma_get_xmit_slave_udp(device, master, ah_attr, flags);
132 put:
133 dev_put(master);
134 return slave;
135 }
136