[PATCH net-next v2 07/11] net/smc: retrieve v2 gid from IB device

Karsten Graul
2021-10-14T16:48:49Z

In smc_ib.c, scan for RoCE devices that support UDP encapsulation.
Find an eligible device and check that there is a route to the
remote peer.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
---
net/smc/smc_core.c | 4 ++-
net/smc/smc_ib.c | 77 ++++++++++++++++++++++++++++++++++++++--------
net/smc/smc_ib.h | 3 +-
net/smc/smc_pnet.c | 41 +++++++++++++++---------
4 files changed, 95 insertions(+), 30 deletions(-)

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index a081582e5669..6bbd71de6bc0 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -715,7 +715,9 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
(rndvec[2] << 16);
rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
- ini->vlan_id, lnk->gid, &lnk->sgid_index);
+ ini->vlan_id, lnk->gid, &lnk->sgid_index,
+ lgr->smc_version == SMC_V2 ?
+ &ini->smcrv2 : NULL);
if (rc)
goto out;
rc = smc_llc_link_init(lnk);
diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
index 9f72910af1d0..d15bacbd73e0 100644
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -17,6 +17,7 @@
#include <linux/scatterlist.h>
#include <linux/wait.h>
#include <linux/mutex.h>
+#include <linux/inetdevice.h>
#include <rdma/ib_verbs.h>
#include <rdma/ib_cache.h>

@@ -62,16 +63,23 @@ static int smc_ib_modify_qp_rtr(struct smc_link *lnk)
IB_QP_STATE | IB_QP_AV | IB_QP_PATH_MTU | IB_QP_DEST_QPN |
IB_QP_RQ_PSN | IB_QP_MAX_DEST_RD_ATOMIC | IB_QP_MIN_RNR_TIMER;
struct ib_qp_attr qp_attr;
+ u8 hop_lim = 1;

memset(&qp_attr, 0, sizeof(qp_attr));
qp_attr.qp_state = IB_QPS_RTR;
qp_attr.path_mtu = min(lnk->path_mtu, lnk->peer_mtu);
qp_attr.ah_attr.type = RDMA_AH_ATTR_TYPE_ROCE;
rdma_ah_set_port_num(&qp_attr.ah_attr, lnk->ibport);
- rdma_ah_set_grh(&qp_attr.ah_attr, NULL, 0, lnk->sgid_index, 1, 0);
+ if (lnk->lgr->smc_version == SMC_V2 && lnk->lgr->uses_gateway)
+ hop_lim = IPV6_DEFAULT_HOPLIMIT;
+ rdma_ah_set_grh(&qp_attr.ah_attr, NULL, 0, lnk->sgid_index, hop_lim, 0);
rdma_ah_set_dgid_raw(&qp_attr.ah_attr, lnk->peer_gid);
- memcpy(&qp_attr.ah_attr.roce.dmac, lnk->peer_mac,
- sizeof(lnk->peer_mac));
+ if (lnk->lgr->smc_version == SMC_V2 && lnk->lgr->uses_gateway)
+ memcpy(&qp_attr.ah_attr.roce.dmac, lnk->lgr->nexthop_mac,
+ sizeof(lnk->lgr->nexthop_mac));
+ else
+ memcpy(&qp_attr.ah_attr.roce.dmac, lnk->peer_mac,
+ sizeof(lnk->peer_mac));
qp_attr.dest_qp_num = lnk->peer_qpn;
qp_attr.rq_psn = lnk->peer_psn; /* starting receive packet seq # */
qp_attr.max_dest_rd_atomic = 1; /* max # of resources for incoming
@@ -210,9 +218,54 @@ int smc_ib_find_route(__be32 saddr, __be32 daddr,
return -ENOENT;
}

+static int smc_ib_determine_gid_rcu(const struct net_device *ndev,
+ const struct ib_gid_attr *attr,
+ u8 gid[], u8 *sgid_index,
+ struct smc_init_info_smcrv2 *smcrv2)
+{
+ if (!smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE) {
+ if (gid)
+ memcpy(gid, &attr->gid, SMC_GID_SIZE);
+ if (sgid_index)
+ *sgid_index = attr->index;
+ return 0;
+ }
+ if (smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
+ smc_ib_gid_to_ipv4((u8 *)&attr->gid) != cpu_to_be32(INADDR_NONE)) {
+ struct in_device *in_dev = __in_dev_get_rcu(ndev);
+ const struct in_ifaddr *ifa;
+ bool subnet_match = false;
+
+ if (!in_dev)
+ goto out;
+ in_dev_for_each_ifa_rcu(ifa, in_dev) {
+ if (!inet_ifa_match(smcrv2->saddr, ifa))
+ continue;
+ subnet_match = true;
+ break;
+ }
+ if (!subnet_match)
+ goto out;
+ if (smcrv2->daddr && smc_ib_find_route(smcrv2->saddr,
+ smcrv2->daddr,
+ smcrv2->nexthop_mac,
+ &smcrv2->uses_gateway))
+ goto out;
+
+ if (gid)
+ memcpy(gid, &attr->gid, SMC_GID_SIZE);
+ if (sgid_index)
+ *sgid_index = attr->index;
+ return 0;
+ }
+out:
+ return -ENODEV;
+}
+
/* determine the gid for an ib-device port and vlan id */
int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
- unsigned short vlan_id, u8 gid[], u8 *sgid_index)
+ unsigned short vlan_id, u8 gid[], u8 *sgid_index,
+ struct smc_init_info_smcrv2 *smcrv2)
{
const struct ib_gid_attr *attr;
const struct net_device *ndev;
@@ -228,15 +281,13 @@ int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
if (!IS_ERR(ndev) &&
((!vlan_id && !is_vlan_dev(ndev)) ||
(vlan_id && is_vlan_dev(ndev) &&
- vlan_dev_vlan_id(ndev) == vlan_id)) &&
- attr->gid_type == IB_GID_TYPE_ROCE) {
- rcu_read_unlock();
- if (gid)
- memcpy(gid, &attr->gid, SMC_GID_SIZE);
- if (sgid_index)
- *sgid_index = attr->index;
- rdma_put_gid_attr(attr);
- return 0;
+ vlan_dev_vlan_id(ndev) == vlan_id))) {
+ if (!smc_ib_determine_gid_rcu(ndev, attr, gid,
+ sgid_index, smcrv2)) {
+ rcu_read_unlock();
+ rdma_put_gid_attr(attr);
+ return 0;
+ }
}
rcu_read_unlock();
rdma_put_gid_attr(attr);
diff --git a/net/smc/smc_ib.h b/net/smc/smc_ib.h
index c55cbd7be67a..07585937370e 100644
--- a/net/smc/smc_ib.h
+++ b/net/smc/smc_ib.h
@@ -101,7 +101,8 @@ void smc_ib_sync_sg_for_device(struct smc_link *lnk,
struct smc_buf_desc *buf_slot,
enum dma_data_direction data_direction);
int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
- unsigned short vlan_id, u8 gid[], u8 *sgid_index);
+ unsigned short vlan_id, u8 gid[], u8 *sgid_index,
+ struct smc_init_info_smcrv2 *smcrv2);
int smc_ib_find_route(__be32 saddr, __be32 daddr,
u8 nexthop_mac[], u8 *uses_gateway);
bool smc_ib_is_valid_local_systemid(void);
diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index 4a964e9190b0..67e9d9fde085 100644
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -953,6 +953,26 @@ static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
return rc;
}

+static int smc_pnet_determine_gid(struct smc_ib_device *ibdev, int i,
+ struct smc_init_info *ini)
+{
+ if (!ini->check_smcrv2 &&
+ !smc_ib_determine_gid(ibdev, i, ini->vlan_id, ini->ib_gid, NULL,
+ NULL)) {
+ ini->ib_dev = ibdev;
+ ini->ib_port = i;
+ return 0;
+ }
+ if (ini->check_smcrv2 &&
+ !smc_ib_determine_gid(ibdev, i, ini->vlan_id, ini->smcrv2.ib_gid_v2,
+ NULL, &ini->smcrv2)) {
+ ini->smcrv2.ib_dev_v2 = ibdev;
+ ini->smcrv2.ib_port_v2 = i;
+ return 0;
+ }
+ return -ENODEV;
+}
+
/* find a roce device for the given pnetid */
static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
struct smc_init_info *ini,
@@ -961,7 +981,6 @@ static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
struct smc_ib_device *ibdev;
int i;

- ini->ib_dev = NULL;
mutex_lock(&smc_ib_devices.mutex);
list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
if (ibdev == known_dev)
@@ -971,12 +990,9 @@ static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
continue;
if (smc_pnet_match(ibdev->pnetid[i - 1], pnet_id) &&
smc_ib_port_active(ibdev, i) &&
- !test_bit(i - 1, ibdev->ports_going_away) &&
- !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
- ini->ib_gid, NULL)) {
- ini->ib_dev = ibdev;
- ini->ib_port = i;
- goto out;
+ !test_bit(i - 1, ibdev->ports_going_away)) {
+ if (!smc_pnet_determine_gid(ibdev, i, ini))
+ goto out;
}
}
}
@@ -1016,12 +1032,9 @@ static void smc_pnet_find_rdma_dev(struct net_device *netdev,
dev_put(ndev);
if (netdev == ndev &&
smc_ib_port_active(ibdev, i) &&
- !test_bit(i - 1, ibdev->ports_going_away) &&
- !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
- ini->ib_gid, NULL)) {
- ini->ib_dev = ibdev;
- ini->ib_port = i;
- break;
+ !test_bit(i - 1, ibdev->ports_going_away)) {
+ if (!smc_pnet_determine_gid(ibdev, i, ini))
+ break;
}
}
}
@@ -1083,8 +1096,6 @@ void smc_pnet_find_roce_resource(struct sock *sk, struct smc_init_info *ini)
{
struct dst_entry *dst = sk_dst_get(sk);

- ini->ib_dev = NULL;
- ini->ib_port = 0;
if (!dst)
goto out;
if (!dst->dev)
--
2.25.1