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 ib_device * device,struct net_device * netdev,struct rdma_ah_attr * ah_attr,gfp_t flags)10 static struct sk_buff *rdma_build_skb(struct ib_device *device,
11 struct net_device *netdev,
12 struct rdma_ah_attr *ah_attr,
13 gfp_t flags)
14 {
15 struct ipv6hdr *ip6h;
16 struct sk_buff *skb;
17 struct ethhdr *eth;
18 struct iphdr *iph;
19 struct udphdr *uh;
20 u8 smac[ETH_ALEN];
21 bool is_ipv4;
22 int hdr_len;
23
24 is_ipv4 = ipv6_addr_v4mapped((struct in6_addr *)ah_attr->grh.dgid.raw);
25 hdr_len = ETH_HLEN + sizeof(struct udphdr) + LL_RESERVED_SPACE(netdev);
26 hdr_len += is_ipv4 ? sizeof(struct iphdr) : sizeof(struct ipv6hdr);
27
28 skb = alloc_skb(hdr_len, flags);
29 if (!skb)
30 return NULL;
31
32 skb->dev = netdev;
33 skb_reserve(skb, hdr_len);
34 skb_push(skb, sizeof(struct udphdr));
35 skb_reset_transport_header(skb);
36 uh = udp_hdr(skb);
37 uh->source =
38 htons(rdma_flow_label_to_udp_sport(ah_attr->grh.flow_label));
39 uh->dest = htons(ROCE_V2_UDP_DPORT);
40 uh->len = htons(sizeof(struct udphdr));
41
42 if (is_ipv4) {
43 skb_push(skb, sizeof(struct iphdr));
44 skb_reset_network_header(skb);
45 iph = ip_hdr(skb);
46 iph->frag_off = 0;
47 iph->version = 4;
48 iph->protocol = IPPROTO_UDP;
49 iph->ihl = 0x5;
50 iph->tot_len = htons(sizeof(struct udphdr) + sizeof(struct
51 iphdr));
52 memcpy(&iph->saddr, ah_attr->grh.sgid_attr->gid.raw + 12,
53 sizeof(struct in_addr));
54 memcpy(&iph->daddr, ah_attr->grh.dgid.raw + 12,
55 sizeof(struct in_addr));
56 } else {
57 skb_push(skb, sizeof(struct ipv6hdr));
58 skb_reset_network_header(skb);
59 ip6h = ipv6_hdr(skb);
60 ip6h->version = 6;
61 ip6h->nexthdr = IPPROTO_UDP;
62 memcpy(&ip6h->flow_lbl, &ah_attr->grh.flow_label,
63 sizeof(*ip6h->flow_lbl));
64 memcpy(&ip6h->saddr, ah_attr->grh.sgid_attr->gid.raw,
65 sizeof(struct in6_addr));
66 memcpy(&ip6h->daddr, ah_attr->grh.dgid.raw,
67 sizeof(struct in6_addr));
68 }
69
70 skb_push(skb, sizeof(struct ethhdr));
71 skb_reset_mac_header(skb);
72 eth = eth_hdr(skb);
73 skb->protocol = eth->h_proto = htons(is_ipv4 ? ETH_P_IP : ETH_P_IPV6);
74 rdma_read_gid_l2_fields(ah_attr->grh.sgid_attr, NULL, smac);
75 memcpy(eth->h_source, smac, ETH_ALEN);
76 memcpy(eth->h_dest, ah_attr->roce.dmac, ETH_ALEN);
77
78 return skb;
79 }
80
rdma_get_xmit_slave_udp(struct ib_device * device,struct net_device * master,struct rdma_ah_attr * ah_attr,gfp_t flags)81 static struct net_device *rdma_get_xmit_slave_udp(struct ib_device *device,
82 struct net_device *master,
83 struct rdma_ah_attr *ah_attr,
84 gfp_t flags)
85 {
86 struct net_device *slave;
87 struct sk_buff *skb;
88
89 skb = rdma_build_skb(device, master, ah_attr, flags);
90 if (!skb)
91 return ERR_PTR(-ENOMEM);
92
93 rcu_read_lock();
94 slave = netdev_get_xmit_slave(master, skb,
95 !!(device->lag_flags &
96 RDMA_LAG_FLAGS_HASH_ALL_SLAVES));
97 if (slave)
98 dev_hold(slave);
99 rcu_read_unlock();
100 kfree_skb(skb);
101 return slave;
102 }
103
rdma_lag_put_ah_roce_slave(struct net_device * xmit_slave)104 void rdma_lag_put_ah_roce_slave(struct net_device *xmit_slave)
105 {
106 if (xmit_slave)
107 dev_put(xmit_slave);
108 }
109
rdma_lag_get_ah_roce_slave(struct ib_device * device,struct rdma_ah_attr * ah_attr,gfp_t flags)110 struct net_device *rdma_lag_get_ah_roce_slave(struct ib_device *device,
111 struct rdma_ah_attr *ah_attr,
112 gfp_t flags)
113 {
114 struct net_device *slave = NULL;
115 struct net_device *master;
116
117 if (!(ah_attr->type == RDMA_AH_ATTR_TYPE_ROCE &&
118 ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
119 ah_attr->grh.flow_label))
120 return NULL;
121
122 rcu_read_lock();
123 master = rdma_read_gid_attr_ndev_rcu(ah_attr->grh.sgid_attr);
124 if (IS_ERR(master)) {
125 rcu_read_unlock();
126 return master;
127 }
128 dev_hold(master);
129 rcu_read_unlock();
130
131 if (!netif_is_bond_master(master))
132 goto put;
133
134 slave = rdma_get_xmit_slave_udp(device, master, ah_attr, flags);
135 put:
136 dev_put(master);
137 return slave;
138 }
139