IB/ipath: Lock and count allocated CQs properly

Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_cq.c b/drivers/infiniband/hw/ipath/ipath_cq.c
index 049221bc590e..00440d5c91e0 100644
--- a/drivers/infiniband/hw/ipath/ipath_cq.c
+++ b/drivers/infiniband/hw/ipath/ipath_cq.c
@@ -177,11 +177,6 @@ struct ib_cq *ipath_create_cq(struct ib_device *ibdev, int entries,
                 goto done;
         }
 
-        if (dev->n_cqs_allocated == ib_ipath_max_cqs) {
-                ret = ERR_PTR(-ENOMEM);
-                goto done;
-        }
-
         /* Allocate the completion queue structure. */
         cq = kmalloc(sizeof(*cq), GFP_KERNEL);
         if (!cq) {
@@ -237,6 +232,16 @@ struct ib_cq *ipath_create_cq(struct ib_device *ibdev, int entries,
         } else
                 cq->ip = NULL;
 
+        spin_lock(&dev->n_cqs_lock);
+        if (dev->n_cqs_allocated == ib_ipath_max_cqs) {
+                spin_unlock(&dev->n_cqs_lock);
+                ret = ERR_PTR(-ENOMEM);
+                goto bail_wc;
+        }
+
+        dev->n_cqs_allocated++;
+        spin_unlock(&dev->n_cqs_lock);
+
         /*
          * ib_create_cq() will initialize cq->ibcq except for cq->ibcq.cqe.
          * The number of entries should be >= the number requested or return
@@ -253,7 +258,6 @@ struct ib_cq *ipath_create_cq(struct ib_device *ibdev, int entries,
 
         ret = &cq->ibcq;
 
-        dev->n_cqs_allocated++;
         goto done;
 
 bail_wc:
@@ -280,7 +284,9 @@ int ipath_destroy_cq(struct ib_cq *ibcq)
         struct ipath_cq *cq = to_icq(ibcq);
 
         tasklet_kill(&cq->comptask);
+        spin_lock(&dev->n_cqs_lock);
         dev->n_cqs_allocated--;
+        spin_unlock(&dev->n_cqs_lock);
         if (cq->ip)
                 kref_put(&cq->ip->ref, ipath_release_mmap_info);
         else