[PATCH 5.8 372/633] RDMA/cma: Remove dead code for kernel rdmacm multicast

Greg Kroah-Hartman
2020-10-27T15:09:58Z

From: Jason Gunthorpe <jgg@nvidia.com>

[ Upstream commit 1bb5091def706732c749df9aae45fbca003696f2 ]

There is no kernel user of RDMA CM multicast so this code managing the
multicast subscription of the kernel-only internal QP is dead. Remove it.

This makes the bug fixes in the next patches much simpler.

Link: https://lore.kernel.org/r/20200902081122.745412-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/core/cma.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 015b2fe509dca..0c3c7b85c65df 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -4289,16 +4289,6 @@ static int cma_ib_mc_handler(int status, struct ib_sa_multicast *multicast)
else
pr_debug_ratelimited("RDMA CM: MULTICAST_ERROR: failed to join multicast. status %d\n",
status);
- mutex_lock(&id_priv->qp_mutex);
- if (!status && id_priv->id.qp) {
- status = ib_attach_mcast(id_priv->id.qp, &multicast->rec.mgid,
- be16_to_cpu(multicast->rec.mlid));
- if (status)
- pr_debug_ratelimited("RDMA CM: MULTICAST_ERROR: failed to attach QP. status %d\n",
- status);
- }
- mutex_unlock(&id_priv->qp_mutex);
-
event.status = status;
event.param.ud.private_data = mc->context;
if (!status) {
@@ -4551,6 +4541,10 @@ int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
struct cma_multicast *mc;
int ret;

+ /* Not supported for kernel QPs */
+ if (WARN_ON(id->qp))
+ return -EINVAL;
+
if (!id->device)
return -EINVAL;

@@ -4605,11 +4599,6 @@ void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr)
list_del(&mc->list);
spin_unlock_irq(&id_priv->lock);

- if (id->qp)
- ib_detach_mcast(id->qp,
- &mc->multicast.ib->rec.mgid,
- be16_to_cpu(mc->multicast.ib->rec.mlid));
-
BUG_ON(id_priv->cma_dev->device != id->device);

if (rdma_cap_ib_mcast(id->device, id->port_num)) {
--
2.25.1