IB/mthca: Make all device methods truly reentrant
Documentation/infiniband/core_locking.txt says:
All of the methods in struct ib_device exported by a low-level
driver must be fully reentrant. The low-level driver is required to
perform all synchronization necessary to maintain consistency, even
if multiple function calls using the same object are run
simultaneously.
However, mthca's modify_qp, modify_srq and resize_cq methods are
currently not reentrant. Add a mutex to the QP, SRQ and CQ structures
so that these calls can be properly serialized.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_srq.c b/drivers/infiniband/hw/mthca/mthca_srq.c
index b292fef..fab417c 100644
--- a/drivers/infiniband/hw/mthca/mthca_srq.c
+++ b/drivers/infiniband/hw/mthca/mthca_srq.c
@@ -243,6 +243,7 @@
spin_lock_init(&srq->lock);
srq->refcount = 1;
init_waitqueue_head(&srq->wait);
+ mutex_init(&srq->mutex);
if (mthca_is_memfree(dev))
mthca_arbel_init_srq_context(dev, pd, srq, mailbox->buf);
@@ -371,7 +372,11 @@
if (attr_mask & IB_SRQ_LIMIT) {
if (attr->srq_limit > srq->max)
return -EINVAL;
+
+ mutex_lock(&srq->mutex);
ret = mthca_ARM_SRQ(dev, srq->srqn, attr->srq_limit, &status);
+ mutex_unlock(&srq->mutex);
+
if (ret)
return ret;
if (status)