RDMA/iw_cxgb4: Low resource fixes for Completion queue

Pre-allocate buffers to deallocate completion queue, so that completion
queue is deallocated during RDMA termination when system is running
out of memory.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/cxgb4/cq.c b/drivers/infiniband/hw/cxgb4/cq.c
index b0b9557..812ab72 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/cq.c
+++ b/drivers/infiniband/hw/cxgb4/cq.c
@@ -33,19 +33,15 @@
 #include "iw_cxgb4.h"
 
 static int destroy_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
-                     struct c4iw_dev_ucontext *uctx)
+                     struct c4iw_dev_ucontext *uctx, struct sk_buff *skb)
 {
        struct fw_ri_res_wr *res_wr;
        struct fw_ri_res *res;
        int wr_len;
        struct c4iw_wr_wait wr_wait;
-       struct sk_buff *skb;
        int ret;
 
        wr_len = sizeof *res_wr + sizeof *res;
-       skb = alloc_skb(wr_len, GFP_KERNEL);
-       if (!skb)
-               return -ENOMEM;
        set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
 
        res_wr = (struct fw_ri_res_wr *)__skb_put(skb, wr_len);
@@ -863,7 +859,9 @@ int c4iw_destroy_cq(struct ib_cq *ib_cq)
        ucontext = ib_cq->uobject ? to_c4iw_ucontext(ib_cq->uobject->context)
                                  : NULL;
        destroy_cq(&chp->rhp->rdev, &chp->cq,
-                  ucontext ? &ucontext->uctx : &chp->cq.rdev->uctx);
+                  ucontext ? &ucontext->uctx : &chp->cq.rdev->uctx,
+                  chp->destroy_skb);
+       chp->destroy_skb = NULL;
        kfree(chp);
        return 0;
 }
@@ -879,7 +877,7 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
        struct c4iw_cq *chp;
        struct c4iw_create_cq_resp uresp;
        struct c4iw_ucontext *ucontext = NULL;
-       int ret;
+       int ret, wr_len;
        size_t memsize, hwentries;
        struct c4iw_mm_entry *mm, *mm2;
 
@@ -896,6 +894,13 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
        if (!chp)
                return ERR_PTR(-ENOMEM);
 
+       wr_len = sizeof(struct fw_ri_res_wr) + sizeof(struct fw_ri_res);
+       chp->destroy_skb = alloc_skb(wr_len, GFP_KERNEL);
+       if (!chp->destroy_skb) {
+               ret = -ENOMEM;
+               goto err1;
+       }
+
        if (ib_context)
                ucontext = to_c4iw_ucontext(ib_context);
 
@@ -936,7 +941,7 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
        ret = create_cq(&rhp->rdev, &chp->cq,
                        ucontext ? &ucontext->uctx : &rhp->rdev.uctx);
        if (ret)
-               goto err1;
+               goto err2;
 
        chp->rhp = rhp;
        chp->cq.size--;                         /* status page */
@@ -947,15 +952,15 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
        init_waitqueue_head(&chp->wait);
        ret = insert_handle(rhp, &rhp->cqidr, chp, chp->cq.cqid);
        if (ret)
-               goto err2;
+               goto err3;
 
        if (ucontext) {
                mm = kmalloc(sizeof *mm, GFP_KERNEL);
                if (!mm)
-                       goto err3;
+                       goto err4;
                mm2 = kmalloc(sizeof *mm2, GFP_KERNEL);
                if (!mm2)
-                       goto err4;
+                       goto err5;
 
                uresp.qid_mask = rhp->rdev.cqmask;
                uresp.cqid = chp->cq.cqid;
@@ -970,7 +975,7 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
                ret = ib_copy_to_udata(udata, &uresp,
                                       sizeof(uresp) - sizeof(uresp.reserved));
                if (ret)
-                       goto err5;
+                       goto err6;
 
                mm->key = uresp.key;
                mm->addr = virt_to_phys(chp->cq.queue);
@@ -986,15 +991,18 @@ struct ib_cq *c4iw_create_cq(struct ib_device *ibdev,
             __func__, chp->cq.cqid, chp, chp->cq.size,
             chp->cq.memsize, (unsigned long long) chp->cq.dma_addr);
        return &chp->ibcq;
-err5:
+err6:
        kfree(mm2);
-err4:
+err5:
        kfree(mm);
-err3:
+err4:
        remove_handle(rhp, &rhp->cqidr, chp->cq.cqid);
-err2:
+err3:
        destroy_cq(&chp->rhp->rdev, &chp->cq,
-                  ucontext ? &ucontext->uctx : &rhp->rdev.uctx);
+                  ucontext ? &ucontext->uctx : &rhp->rdev.uctx,
+                  chp->destroy_skb);
+err2:
+       kfree_skb(chp->destroy_skb);
 err1:
        kfree(chp);
        return ERR_PTR(ret);

diff --git a/drivers/infiniband/hw/cxgb4/iw_cxgb4.h b/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
index e94ec0d..c5f5881 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
+++ b/drivers/infiniband/hw/cxgb4/iw_cxgb4.h
@@ -414,6 +414,7 @@ static inline struct c4iw_mw *to_c4iw_mw(struct ib_mw *ibmw)
 struct c4iw_cq {
        struct ib_cq ibcq;
        struct c4iw_dev *rhp;
+       struct sk_buff *destroy_skb;
        struct t4_cq cq;
        spinlock_t lock;
        spinlock_t comp_handler_lock;