[ofw][mlx4] SRQ attached QP issue

[Anatoly Greenblatt]

Hi,
 
What about mthca? Is this thing allowed in non connectx hcas?
 
Thanks,
Anatoly.

________________________________

From: ofw-bounces at lists.openfabrics.org on behalf of Alex Estrin
Sent: Sat 9/27/2008 1:20 AM
To: Leonid Keller
Cc: ofw at lists.openfabrics.org
Subject: [ofw][mlx4] SRQ attached QP issue



Hello,

This patch seem fixed the create-QP-attached-to-SRQ issue.
I didn't verify though, if code allowes send queue zero size. Included
check anyway.
Please review.

Thanks,
Alex.

Index: mlx4/kernel/bus/ib/qp.c
===================================================================
--- mlx4/kernel/bus/ib/qp.c     (revision 1622)
+++ mlx4/kernel/bus/ib/qp.c     (working copy)
@@ -411,14 +411,20 @@
                err = mlx4_buf_write_mtt(dev->dev, &qp->mtt, &qp->buf);
                if (err)
                        goto err_mtt;
-
-               qp->sq.wrid  = kmalloc(qp->sq.wqe_cnt * sizeof (u64),
GFP_KERNEL);
-               qp->rq.wrid  = kmalloc(qp->rq.wqe_cnt * sizeof (u64),
GFP_KERNEL);
-
-               if (!qp->sq.wrid || !qp->rq.wrid) {
-                       err = -ENOMEM;
-                       goto err_wrid;
+               if (qp->sq.wqe_cnt) {
+                       qp->sq.wrid  = kmalloc(qp->sq.wqe_cnt * sizeof
(u64), GFP_KERNEL);
+                       if (!qp->sq.wrid) {
+                               err = -ENOMEM;
+                               goto err_wrid;
+                       }
                }
+               if (qp->rq.wqe_cnt) {
+                       qp->rq.wrid  = kmalloc(qp->rq.wqe_cnt * sizeof
(u64), GFP_KERNEL);
+                       if (!qp->rq.wrid) {
+                               err = -ENOMEM;
+                               goto err_wrid;
+                       }
+               }
        }

        if (!sqpn)
@@ -452,8 +458,10 @@
                        mlx4_ib_db_unmap_user(to_mucontext(pd->p_uctx),
                                              &qp->db);
        } else {
-               kfree(qp->sq.wrid);
-               kfree(qp->rq.wrid);
+               if (qp->sq.wrid)
+                       kfree(qp->sq.wrid);
+               if (qp->rq.wrid)
+                       kfree(qp->rq.wrid);
        }

 err_mtt:



> Hello,
>
> It seem there is a controversy exist in mlx4 driver that
> won't allow to create QP if it was attached to SRQ.
>
> At first it doesn't allow to set any recv queue size (which is fine)
>
> mlx4\kernel\bus\ib\qp.c@ line 219:
>               if (cap->max_recv_wr)
>                       return -EINVAL;
>
>               qp->rq.wqe_cnt = qp->rq.max_gs = 0;
>
> But then there is assertion for zero size memory request in 'kmalloc':
> mlx4\kernel\bus\ib\qp.c @ line 416:
>
>               qp->rq.wrid  = kmalloc(qp->rq.wqe_cnt * sizeof
> (u64), GFP_KERNEL);
>              
> mlx4\kernel\inc\l2w_memory.h @ line 81:
>
>               static inline void * kmalloc( SIZE_T bsize,
> gfp_t gfp_mask)
>               {
>                       void *ptr;
>                       ASSERT( KeGetCurrentIrql() <= DISPATCH_LEVEL);
>                       ASSERT(bsize);
>               .....
>
> I believe it was added for a reason.
> Please let me know if I missed anything.
>
> Thanks,
> Alex.
>
>
>