[PATCH] IB/srpt: Increase port count

[PATCH] IB/srpt: Increase port count

[Bart Van Assche]

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@opengridcomputing.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: <stable@vger.kernel.org>
---
 drivers/infiniband/ulp/srpt/ib_srpt.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.h b/drivers/infiniband/ulp/srpt/ib_srpt.h
index 2361483476a0..b72f1f4066fa 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.h
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.h
@@ -410,7 +410,7 @@ struct srpt_device {
 	struct mutex		sdev_mutex;
 	bool			use_srq;
 	struct srpt_recv_ioctx	**ioctx_ring;
-	struct srpt_port	port[2];
+	struct srpt_port	port[4];
 	struct ib_event_handler	event_handler;
 	struct list_head	list;
 };
-- 
2.16.3

Re: [PATCH] IB/srpt: Increase port count

[Christoph Hellwig]

On Thu, May 10, 2018 at 03:32:09PM -0700, Bart Van Assche wrote:
> 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));

Should we add a IB_MAX_PORTS define that ULPs can rely on in the core?

Re: [PATCH] IB/srpt: Increase port count

[Bart Van Assche]

On Mon, 2018-05-14 at 05:03 -0700, Christoph Hellwig wrote:
> On Thu, May 10, 2018 at 03:32:09PM -0700, Bart Van Assche wrote:
> > 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));
> 
> Should we add a IB_MAX_PORTS define that ULPs can rely on in the core?

How many drivers would benefit from the introduction of such a constant?
A third possible alternative is that I change the port array in the ib_srpt
driver such that it is allocated dynamically. That would allow to eliminate
the WARN_ON() statement mentioned above.

Bart.

Re: [PATCH] IB/srpt: Increase port count

[hch]

On Mon, May 14, 2018 at 02:23:16PM +0000, Bart Van Assche wrote:
> > >     WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
> > 
> > Should we add a IB_MAX_PORTS define that ULPs can rely on in the core?
> 
> How many drivers would benefit from the introduction of such a constant?
> A third possible alternative is that I change the port array in the ib_srpt
> driver such that it is allocated dynamically. That would allow to eliminate
> the WARN_ON() statement mentioned above.

No idea how many benefit.  But either we have an upper limit, or
ULPs should be able to deal with any possible number, e.g. by using
your dynamic allocation idea.