[PATCH 3.16 014/328] IB/srpt: Support HCAs with more than two ports

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Bart Van Assche <bart.vanassche@xxxxxxx>

commit e620ebfc228dcbef7519e3d16f43c6c6f1a1d0cb upstream.

Since there are adapters that have four ports, increase the size of
the srpt_device.port[] array. This patch avoids that the following
warning is hit with quad port Chelsio adapters:

    WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));

Reported-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Reviewed-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
[bwh: Backported to 3.16:
 - Use inline calculation instead of struct_size; the number of ports is not
   user-controlled so no overflow check is needed
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -3147,7 +3147,9 @@ static void srpt_add_one(struct ib_devic
 	pr_debug("device = %p, device->dma_ops = %p\n", device,
 		 device->dma_ops);
 
-	sdev = kzalloc(sizeof *sdev, GFP_KERNEL);
+	sdev = kzalloc(sizeof(*sdev) +
+		       device->phys_port_cnt * sizeof(*sdev->port),
+		       GFP_KERNEL);
 	if (!sdev)
 		goto err;
 
@@ -3220,8 +3222,6 @@ static void srpt_add_one(struct ib_devic
 	for (i = 0; i < sdev->srq_size; ++i)
 		srpt_post_recv(sdev, sdev->ioctx_ring[i]);
 
-	WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
-
 	for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
 		sport = &sdev->port[i - 1];
 		sport->sdev = sdev;
--- a/drivers/infiniband/ulp/srpt/ib_srpt.h
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.h
@@ -387,9 +387,9 @@ struct srpt_port {
  * @rch_list:      Per-device channel list -- see also srpt_rdma_ch.list.
  * @ch_releaseQ:   Enables waiting for removal from rch_list.
  * @spinlock:      Protects rch_list and tpg.
- * @port:          Information about the ports owned by this HCA.
  * @event_handler: Per-HCA asynchronous IB event handler.
  * @list:          Node in srpt_dev_list.
+ * @port:          Information about the ports owned by this HCA.
  */
 struct srpt_device {
 	struct ib_device	*device;
@@ -403,9 +403,9 @@ struct srpt_device {
 	struct list_head	rch_list;
 	wait_queue_head_t	ch_releaseQ;
 	spinlock_t		spinlock;
-	struct srpt_port	port[2];
 	struct ib_event_handler	event_handler;
 	struct list_head	list;
+	struct srpt_port        port[];
 };
 
 /**