[IB] mthca: SRQ limit reached events

Our hardware supports generating an event when the number of receives
posted to a shared receive queue (SRQ) falls below a user-specified
limit.  Implement mthca_modify_srq() to arm the limit, and add code to
handle dispatching SRQ events when they occur.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

4 files changed, 45 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h
index 67a2f324a274..6e18c128af42 100644
--- a/drivers/infiniband/hw/mthca/mthca_dev.h
+++ b/drivers/infiniband/hw/mthca/mthca_dev.h
@@ -448,6 +448,8 @@ void mthca_cq_clean(struct mthca_dev *dev, u32 cqn, u32 qpn,
 int mthca_alloc_srq(struct mthca_dev *dev, struct mthca_pd *pd,
                     struct ib_srq_attr *attr, struct mthca_srq *srq);
 void mthca_free_srq(struct mthca_dev *dev, struct mthca_srq *srq);
+int mthca_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
+                     enum ib_srq_attr_mask attr_mask);
 void mthca_srq_event(struct mthca_dev *dev, u32 srqn,
                      enum ib_event_type event_type);
 void mthca_free_srq_wqe(struct mthca_srq *srq, u32 wqe_addr);
diff --git a/drivers/infiniband/hw/mthca/mthca_eq.c b/drivers/infiniband/hw/mthca/mthca_eq.c
index c81fa8e975ef..f2afdc6c7e60 100644
--- a/drivers/infiniband/hw/mthca/mthca_eq.c
+++ b/drivers/infiniband/hw/mthca/mthca_eq.c
@@ -83,7 +83,8 @@ enum {
         MTHCA_EVENT_TYPE_PATH_MIG           = 0x01,
         MTHCA_EVENT_TYPE_COMM_EST           = 0x02,
         MTHCA_EVENT_TYPE_SQ_DRAINED         = 0x03,
-        MTHCA_EVENT_TYPE_SRQ_LAST_WQE       = 0x13,
+        MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE    = 0x13,
+        MTHCA_EVENT_TYPE_SRQ_LIMIT          = 0x14,
         MTHCA_EVENT_TYPE_CQ_ERROR           = 0x04,
         MTHCA_EVENT_TYPE_WQ_CATAS_ERROR     = 0x05,
         MTHCA_EVENT_TYPE_EEC_CATAS_ERROR    = 0x06,
@@ -110,8 +111,9 @@ enum {
                                 (1ULL << MTHCA_EVENT_TYPE_LOCAL_CATAS_ERROR)  | \
                                 (1ULL << MTHCA_EVENT_TYPE_PORT_CHANGE)        | \
                                 (1ULL << MTHCA_EVENT_TYPE_ECC_DETECT))
-#define MTHCA_SRQ_EVENT_MASK    (1ULL << MTHCA_EVENT_TYPE_SRQ_CATAS_ERROR)    | \
-                                (1ULL << MTHCA_EVENT_TYPE_SRQ_LAST_WQE)
+#define MTHCA_SRQ_EVENT_MASK   ((1ULL << MTHCA_EVENT_TYPE_SRQ_CATAS_ERROR)    | \
+                                (1ULL << MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE)    | \
+                                (1ULL << MTHCA_EVENT_TYPE_SRQ_LIMIT))
 #define MTHCA_CMD_EVENT_MASK    (1ULL << MTHCA_EVENT_TYPE_CMD)
 
 #define MTHCA_EQ_DB_INC_CI     (1 << 24)
@@ -142,6 +144,9 @@ struct mthca_eqe {
                         __be32 qpn;
                 } __attribute__((packed)) qp;
                 struct {
+                        __be32 srqn;
+                } __attribute__((packed)) srq;
+                struct {
                         __be32 cqn;
                         u32    reserved1;
                         u8     reserved2[3];
@@ -305,6 +310,16 @@ static int mthca_eq_int(struct mthca_dev *dev, struct mthca_eq *eq)
                                        IB_EVENT_SQ_DRAINED);
                         break;
 
+                case MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE:
+                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
+                                       IB_EVENT_QP_LAST_WQE_REACHED);
+                        break;
+
+                case MTHCA_EVENT_TYPE_SRQ_LIMIT:
+                        mthca_srq_event(dev, be32_to_cpu(eqe->event.srq.srqn) & 0xffffff,
+                                        IB_EVENT_SRQ_LIMIT_REACHED);
+                        break;
+
                 case MTHCA_EVENT_TYPE_WQ_CATAS_ERROR:
                         mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                        IB_EVENT_QP_FATAL);
diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 4e87ad115712..53b29a0841bf 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -1084,6 +1084,7 @@ int mthca_register_device(struct mthca_dev *dev)
 
         if (dev->mthca_flags & MTHCA_FLAG_SRQ) {
                 dev->ib_dev.create_srq           = mthca_create_srq;
+                dev->ib_dev.modify_srq           = mthca_modify_srq;
                 dev->ib_dev.destroy_srq          = mthca_destroy_srq;
 
                 if (mthca_is_memfree(dev))
diff --git a/drivers/infiniband/hw/mthca/mthca_srq.c b/drivers/infiniband/hw/mthca/mthca_srq.c
index 18998d48c53e..13d2290261d9 100644
--- a/drivers/infiniband/hw/mthca/mthca_srq.c
+++ b/drivers/infiniband/hw/mthca/mthca_srq.c
@@ -332,6 +332,29 @@ void mthca_free_srq(struct mthca_dev *dev, struct mthca_srq *srq)
         mthca_free_mailbox(dev, mailbox);
 }
 
+int mthca_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
+                     enum ib_srq_attr_mask attr_mask)
+{       
+        struct mthca_dev *dev = to_mdev(ibsrq->device);
+        struct mthca_srq *srq = to_msrq(ibsrq);
+        int ret;
+        u8 status;
+
+        /* We don't support resizing SRQs (yet?) */
+        if (attr_mask & IB_SRQ_MAX_WR)
+                return -EINVAL;
+
+        if (attr_mask & IB_SRQ_LIMIT) {
+                ret = mthca_ARM_SRQ(dev, srq->srqn, attr->srq_limit, &status);
+                if (ret)
+                        return ret;
+                if (status)
+                        return -EINVAL;
+        }
+
+        return 0;
+}
+
 void mthca_srq_event(struct mthca_dev *dev, u32 srqn,
                      enum ib_event_type event_type)
 {
@@ -354,7 +377,7 @@ void mthca_srq_event(struct mthca_dev *dev, u32 srqn,
 
         event.device      = &dev->ib_dev;
         event.event       = event_type;
-        event.element.srq  = &srq->ibsrq;
+        event.element.srq = &srq->ibsrq;
         srq->ibsrq.event_handler(&event, srq->ibsrq.srq_context);
 
 out: