[PATCH net-next v2 11/11] net/smc: stop links when their GID is removed

Karsten Graul
2021-10-14T16:48:56Z

With SMC-Rv2 the GID is an IP address that can be deleted from the
device. When an IB_EVENT_GID_CHANGE event is provided then iterate over
all active links and check if their GID is still defined. Otherwise
stop the affected link.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
---
net/smc/smc_ib.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)

diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c
index 32f9d2fdc474..d93055ec17ae 100644
--- a/net/smc/smc_ib.c
+++ b/net/smc/smc_ib.c
@@ -295,6 +295,58 @@ int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
return -ENODEV;
}

+/* check if gid is still defined on smcibdev */
+static bool smc_ib_check_link_gid(u8 gid[SMC_GID_SIZE], bool smcrv2,
+ struct smc_ib_device *smcibdev, u8 ibport)
+{
+ const struct ib_gid_attr *attr;
+ bool rc = false;
+ int i;
+
+ for (i = 0; !rc && i < smcibdev->pattr[ibport - 1].gid_tbl_len; i++) {
+ attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, i);
+ if (IS_ERR(attr))
+ continue;
+
+ rcu_read_lock();
+ if ((!smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE) ||
+ (smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
+ !(ipv6_addr_type((const struct in6_addr *)&attr->gid)
+ & IPV6_ADDR_LINKLOCAL)))
+ if (!memcmp(gid, &attr->gid, SMC_GID_SIZE))
+ rc = true;
+ rcu_read_unlock();
+ rdma_put_gid_attr(attr);
+ }
+ return rc;
+}
+
+/* check all links if the gid is still defined on smcibdev */
+static void smc_ib_gid_check(struct smc_ib_device *smcibdev, u8 ibport)
+{
+ struct smc_link_group *lgr;
+ int i;
+
+ spin_lock_bh(&smc_lgr_list.lock);
+ list_for_each_entry(lgr, &smc_lgr_list.list, list) {
+ if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
+ SMC_MAX_PNETID_LEN))
+ continue; /* lgr is not affected */
+ if (list_empty(&lgr->list))
+ continue;
+ for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
+ if (lgr->lnk[i].state == SMC_LNK_UNUSED ||
+ lgr->lnk[i].smcibdev != smcibdev)
+ continue;
+ if (!smc_ib_check_link_gid(lgr->lnk[i].gid,
+ lgr->smc_version == SMC_V2,
+ smcibdev, ibport))
+ smcr_port_err(smcibdev, ibport);
+ }
+ }
+ spin_unlock_bh(&smc_lgr_list.lock);
+}
+
static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport)
{
int rc;
@@ -333,6 +385,7 @@ static void smc_ib_port_event_work(struct work_struct *work)
} else {
clear_bit(port_idx, smcibdev->ports_going_away);
smcr_port_add(smcibdev, port_idx + 1);
+ smc_ib_gid_check(smcibdev, port_idx + 1);
}
}
}
--
2.25.1