[PATCH V2 mlx5-next 05/10] RDMA/core: Add LAG functionality

Maor Gottlieb
2020-04-20T07:54:38Z

Add support to get the RoCE LAG xmit slave by building skb
of the RoCE packet and call to master_xmit_slave_get.
If driver wants to get the slave assume all slaves are available,
then need to set RDMA_LAG_FLAGS_HASH_ALL_SLAVES in flags.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
---
drivers/infiniband/core/Makefile | 2 +-
drivers/infiniband/core/lag.c | 139 +++++++++++++++++++++++++++++++
include/rdma/ib_verbs.h | 2 +
include/rdma/lag.h | 22 +++++
4 files changed, 164 insertions(+), 1 deletion(-)
create mode 100644 drivers/infiniband/core/lag.c
create mode 100644 include/rdma/lag.h

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index d1b14887960e..870f0fcd54d5 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -12,7 +12,7 @@ ib_core-y := packer.o ud_header.o verbs.o cq.o rw.o sysfs.o \
roce_gid_mgmt.o mr_pool.o addr.o sa_query.o \
multicast.o mad.o smi.o agent.o mad_rmpp.o \
nldev.o restrack.o counters.o ib_core_uverbs.o \
- trace.o
+ trace.o lag.o

ib_core-$(CONFIG_SECURITY_INFINIBAND) += security.o
ib_core-$(CONFIG_CGROUP_RDMA) += cgroup.o
diff --git a/drivers/infiniband/core/lag.c b/drivers/infiniband/core/lag.c
new file mode 100644
index 000000000000..007c06cae3d8
--- /dev/null
+++ b/drivers/infiniband/core/lag.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright (c) 2020 Mellanox Technologies. All rights reserved.
+ */
+
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_cache.h>
+#include <rdma/lag.h>
+
+static struct sk_buff *rdma_build_skb(struct ib_device *device,
+ struct net_device *netdev,
+ struct rdma_ah_attr *ah_attr)
+{
+ struct ipv6hdr *ip6h;
+ struct sk_buff *skb;
+ struct ethhdr *eth;
+ struct iphdr *iph;
+ struct udphdr *uh;
+ u8 smac[ETH_ALEN];
+ bool is_ipv4;
+ int hdr_len;
+
+ is_ipv4 = ipv6_addr_v4mapped((struct in6_addr *)ah_attr->grh.dgid.raw);
+ hdr_len = ETH_HLEN + sizeof(struct udphdr) + LL_RESERVED_SPACE(netdev);
+ hdr_len += is_ipv4 ? sizeof(struct iphdr) : sizeof(struct ipv6hdr);
+
+ skb = alloc_skb(hdr_len, GFP_ATOMIC);
+ if (!skb)
+ return NULL;
+
+ skb->dev = netdev;
+ skb_reserve(skb, hdr_len);
+ skb_push(skb, sizeof(struct udphdr));
+ skb_reset_transport_header(skb);
+ uh = udp_hdr(skb);
+ uh->source = htons(0xC000);
+ uh->dest = htons(ROCE_V2_UDP_DPORT);
+ uh->len = htons(sizeof(struct udphdr));
+
+ if (is_ipv4) {
+ skb_push(skb, sizeof(struct iphdr));
+ skb_reset_network_header(skb);
+ iph = ip_hdr(skb);
+ iph->frag_off = 0;
+ iph->version = 4;
+ iph->protocol = IPPROTO_UDP;
+ iph->ihl = 0x5;
+ iph->tot_len = htons(sizeof(struct udphdr) + sizeof(struct
+ iphdr));
+ memcpy(&iph->saddr, ah_attr->grh.sgid_attr->gid.raw + 12,
+ sizeof(struct in_addr));
+ memcpy(&iph->daddr, ah_attr->grh.dgid.raw + 12,
+ sizeof(struct in_addr));
+ } else {
+ skb_push(skb, sizeof(struct ipv6hdr));
+ skb_reset_network_header(skb);
+ ip6h = ipv6_hdr(skb);
+ ip6h->version = 6;
+ ip6h->nexthdr = IPPROTO_UDP;
+ memcpy(&ip6h->flow_lbl, &ah_attr->grh.flow_label,
+ sizeof(*ip6h->flow_lbl));
+ memcpy(&ip6h->saddr, ah_attr->grh.sgid_attr->gid.raw,
+ sizeof(struct in6_addr));
+ memcpy(&ip6h->daddr, ah_attr->grh.dgid.raw,
+ sizeof(struct in6_addr));
+ }
+
+ skb_push(skb, sizeof(struct ethhdr));
+ skb_reset_mac_header(skb);
+ eth = eth_hdr(skb);
+ skb->protocol = eth->h_proto = htons(is_ipv4 ? ETH_P_IP : ETH_P_IPV6);
+ rdma_read_gid_l2_fields(ah_attr->grh.sgid_attr, NULL, smac);
+ memcpy(eth->h_source, smac, ETH_ALEN);
+ memcpy(eth->h_dest, ah_attr->roce.dmac, ETH_ALEN);
+
+ return skb;
+}
+
+static struct net_device *rdma_get_xmit_slave_udp(struct ib_device *device,
+ struct net_device *master,
+ struct rdma_ah_attr *ah_attr)
+{
+ struct net_device *slave;
+ struct sk_buff *skb;
+ u16 flags;
+
+ skb = rdma_build_skb(device, master, ah_attr);
+ if (!skb)
+ return NULL;
+
+ flags = device->lag_flags & RDMA_LAG_FLAGS_HASH_ALL_SLAVES ?
+ LAG_FLAGS_HASH_ALL_SLAVES : 0;
+ slave = master_xmit_get_slave(master, skb, flags);
+ kfree_skb(skb);
+ return slave;
+}
+
+void rdma_lag_put_ah_roce_slave(struct rdma_ah_attr *ah_attr)
+{
+ if (ah_attr->roce.xmit_slave)
+ dev_put(ah_attr->roce.xmit_slave);
+}
+
+int rdma_lag_get_ah_roce_slave(struct ib_device *device,
+ struct rdma_ah_attr *ah_attr)
+{
+ struct net_device *master;
+ struct net_device *slave;
+
+ if (!(ah_attr->type == RDMA_AH_ATTR_TYPE_ROCE &&
+ ah_attr->grh.sgid_attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP))
+ return 0;
+
+ rcu_read_lock();
+ master = rdma_read_gid_attr_ndev_rcu(ah_attr->grh.sgid_attr);
+ if (IS_ERR(master)) {
+ rcu_read_unlock();
+ return PTR_ERR(master);
+ }
+ dev_hold(master);
+ rcu_read_unlock();
+
+ if (!netif_is_bond_master(master)) {
+ dev_put(master);
+ return 0;
+ }
+
+ slave = rdma_get_xmit_slave_udp(device, master, ah_attr);
+
+ dev_put(master);
+ if (!slave) {
+ ibdev_warn(device, "Failed to get lag xmit slave\n");
+ return -EINVAL;
+ }
+
+ ah_attr->roce.xmit_slave = slave;
+
+ return 0;
+}
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index bbc5cfb57cd2..60f9969b6d83 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -894,6 +894,7 @@ struct ib_ah_attr {

struct roce_ah_attr {
u8 dmac[ETH_ALEN];
+ struct net_device *xmit_slave;
};

struct opa_ah_attr {
@@ -2709,6 +2710,7 @@ struct ib_device {
/* Used by iWarp CM */
char iw_ifname[IFNAMSIZ];
u32 iw_driver_flags;
+ u32 lag_flags;
};

struct ib_client_nl_info;
diff --git a/include/rdma/lag.h b/include/rdma/lag.h
new file mode 100644
index 000000000000..a71511824207
--- /dev/null
+++ b/include/rdma/lag.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2020 Mellanox Technologies. All rights reserved.
+ */
+
+#ifndef _RDMA_LAG_H_
+#define _RDMA_LAG_H_
+
+#include <net/lag.h>
+
+struct ib_device;
+struct rdma_ah_attr;
+
+enum rdma_lag_flags {
+ RDMA_LAG_FLAGS_HASH_ALL_SLAVES = 1 << 0
+};
+
+void rdma_lag_put_ah_roce_slave(struct rdma_ah_attr *ah_attr);
+int rdma_lag_get_ah_roce_slave(struct ib_device *device,
+ struct rdma_ah_attr *ah_attr);
+
+#endif /* _RDMA_LAG_H_ */
--
2.17.2