i40iw: Extend port reuse support for listeners

If two listeners are created with different IP's but
same port, the second rdma_listen fails due to a
duplicate port entry being added from the CQP add
APBVT OP. commit f16dc0aa5ea2 ("i40iw: Add support
for port reuse on active side connections") does not
account for listener side port reuse.

Check for duplicate port before invoking the CQP command
to add APBVT entry and delete the entry only if the port
is not in use. Additionally, consolidate all port-reuse
logic into i40iw_manage_apbvt.

Fixes: f16dc0aa5ea2 ("i40iw: Add support for port reuse on active side connections")
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 31 insertions, 3 deletions

diff --git a/drivers/infiniband/hw/i40iw/i40iw_hw.c b/drivers/infiniband/hw/i40iw/i40iw_hw.c
index 6139836fb533..414a36ce16af 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_hw.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_hw.c
@@ -443,13 +443,37 @@ void i40iw_process_aeq(struct i40iw_device *iwdev)
 int i40iw_manage_apbvt(struct i40iw_device *iwdev, u16 accel_local_port, bool add_port)
 {
 	struct i40iw_apbvt_info *info;
-	enum i40iw_status_code status;
 	struct i40iw_cqp_request *cqp_request;
 	struct cqp_commands_info *cqp_info;
+	unsigned long flags;
+	struct i40iw_cm_core *cm_core = &iwdev->cm_core;
+	enum i40iw_status_code status = 0;
+	bool in_use;
+
+	/* apbvt_lock is held across CQP delete APBVT OP (non-waiting) to
+	 * protect against race where add APBVT CQP can race ahead of the delete
+	 * APBVT for same port.
+	 */
+	spin_lock_irqsave(&cm_core->apbvt_lock, flags);
+
+	if (!add_port) {
+		in_use = i40iw_port_in_use(cm_core, accel_local_port);
+		if (in_use)
+			goto exit;
+		clear_bit(accel_local_port, cm_core->ports_in_use);
+	} else {
+		in_use = test_and_set_bit(accel_local_port,
+					  cm_core->ports_in_use);
+		spin_unlock_irqrestore(&cm_core->apbvt_lock, flags);
+		if (in_use)
+			return 0;
+	}
 
 	cqp_request = i40iw_get_cqp_request(&iwdev->cqp, add_port);
-	if (!cqp_request)
-		return -ENOMEM;
+	if (!cqp_request) {
+		status = -ENOMEM;
+		goto exit;
+	}
 
 	cqp_info = &cqp_request->info;
 	info = &cqp_info->in.u.manage_apbvt_entry.info;
@@ -465,6 +489,10 @@ int i40iw_manage_apbvt(struct i40iw_device *iwdev, u16 accel_local_port, bool ad
 	status = i40iw_handle_cqp_op(iwdev, cqp_request);
 	if (status)
 		i40iw_pr_err("CQP-OP Manage APBVT entry fail");
+exit:
+	if (!add_port)
+		spin_unlock_irqrestore(&cm_core->apbvt_lock, flags);
+
 	return status;
 }