[PATCH] IB: Add SRQ support to midlayer

Make the required core API additions and changes for
shared receive queues (SRQs).

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

2 files changed, 158 insertions, 5 deletions

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index c301a2c41f34..c035510c5a36 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -154,6 +154,66 @@ int ib_destroy_ah(struct ib_ah *ah)
 }
 EXPORT_SYMBOL(ib_destroy_ah);
 
+/* Shared receive queues */
+
+struct ib_srq *ib_create_srq(struct ib_pd *pd,
+                             struct ib_srq_init_attr *srq_init_attr)
+{
+        struct ib_srq *srq;
+
+        if (!pd->device->create_srq)
+                return ERR_PTR(-ENOSYS);
+
+        srq = pd->device->create_srq(pd, srq_init_attr, NULL);
+
+        if (!IS_ERR(srq)) {
+                srq->device        = pd->device;
+                srq->pd            = pd;
+                srq->uobject       = NULL;
+                srq->event_handler = srq_init_attr->event_handler;
+                srq->srq_context   = srq_init_attr->srq_context;
+                atomic_inc(&pd->usecnt);
+                atomic_set(&srq->usecnt, 0);
+        }
+
+        return srq;
+}
+EXPORT_SYMBOL(ib_create_srq);
+
+int ib_modify_srq(struct ib_srq *srq,
+                  struct ib_srq_attr *srq_attr,
+                  enum ib_srq_attr_mask srq_attr_mask)
+{
+        return srq->device->modify_srq(srq, srq_attr, srq_attr_mask);
+}
+EXPORT_SYMBOL(ib_modify_srq);
+
+int ib_query_srq(struct ib_srq *srq,
+                 struct ib_srq_attr *srq_attr)
+{
+        return srq->device->query_srq ?
+                srq->device->query_srq(srq, srq_attr) : -ENOSYS;
+}
+EXPORT_SYMBOL(ib_query_srq);
+
+int ib_destroy_srq(struct ib_srq *srq)
+{
+        struct ib_pd *pd;
+        int ret;
+
+        if (atomic_read(&srq->usecnt))
+                return -EBUSY;
+
+        pd = srq->pd;
+
+        ret = srq->device->destroy_srq(srq);
+        if (!ret)
+                atomic_dec(&pd->usecnt);
+
+        return ret;
+}
+EXPORT_SYMBOL(ib_destroy_srq);
+
 /* Queue pairs */
 
 struct ib_qp *ib_create_qp(struct ib_pd *pd,
diff --git a/drivers/infiniband/include/ib_verbs.h b/drivers/infiniband/include/ib_verbs.h
index 042a7d11fbcc..e16cf94870f2 100644
--- a/drivers/infiniband/include/ib_verbs.h
+++ b/drivers/infiniband/include/ib_verbs.h
@@ -256,7 +256,10 @@ enum ib_event_type {
         IB_EVENT_PORT_ERR,
         IB_EVENT_LID_CHANGE,
         IB_EVENT_PKEY_CHANGE,
-        IB_EVENT_SM_CHANGE
+        IB_EVENT_SM_CHANGE,
+        IB_EVENT_SRQ_ERR,
+        IB_EVENT_SRQ_LIMIT_REACHED,
+        IB_EVENT_QP_LAST_WQE_REACHED
 };
 
 struct ib_event {
@@ -264,6 +267,7 @@ struct ib_event {
         union {
                 struct ib_cq    *cq;
                 struct ib_qp    *qp;
+                struct ib_srq   *srq;
                 u8              port_num;
         } element;
         enum ib_event_type      event;
@@ -386,6 +390,23 @@ enum ib_cq_notify {
         IB_CQ_NEXT_COMP
 };
 
+enum ib_srq_attr_mask {
+        IB_SRQ_MAX_WR   = 1 << 0,
+        IB_SRQ_LIMIT    = 1 << 1,
+};
+
+struct ib_srq_attr {
+        u32     max_wr;
+        u32     max_sge;
+        u32     srq_limit;
+};
+
+struct ib_srq_init_attr {
+        void                  (*event_handler)(struct ib_event *, void *);
+        void                   *srq_context;
+        struct ib_srq_attr      attr;
+};
+
 struct ib_qp_cap {
         u32     max_send_wr;
         u32     max_recv_wr;
@@ -713,10 +734,11 @@ struct ib_cq {
 };
 
 struct ib_srq {
-        struct ib_device        *device;
-        struct ib_uobject       *uobject;
-        struct ib_pd            *pd;
-        void                    *srq_context;
+        struct ib_device       *device;
+        struct ib_pd           *pd;
+        struct ib_uobject      *uobject;
+        void                  (*event_handler)(struct ib_event *, void *);
+        void                   *srq_context;
         atomic_t                usecnt;
 };
 
@@ -830,6 +852,18 @@ struct ib_device {
         int                        (*query_ah)(struct ib_ah *ah,
                                                struct ib_ah_attr *ah_attr);
         int                        (*destroy_ah)(struct ib_ah *ah);
+        struct ib_srq *            (*create_srq)(struct ib_pd *pd,
+                                                 struct ib_srq_init_attr *srq_init_attr,
+                                                 struct ib_udata *udata);
+        int                        (*modify_srq)(struct ib_srq *srq,
+                                                 struct ib_srq_attr *srq_attr,
+                                                 enum ib_srq_attr_mask srq_attr_mask);
+        int                        (*query_srq)(struct ib_srq *srq,
+                                                struct ib_srq_attr *srq_attr);
+        int                        (*destroy_srq)(struct ib_srq *srq);
+        int                        (*post_srq_recv)(struct ib_srq *srq,
+                                                    struct ib_recv_wr *recv_wr,
+                                                    struct ib_recv_wr **bad_recv_wr);
         struct ib_qp *             (*create_qp)(struct ib_pd *pd,
                                                 struct ib_qp_init_attr *qp_init_attr,
                                                 struct ib_udata *udata);
@@ -1042,6 +1076,65 @@ int ib_query_ah(struct ib_ah *ah, struct ib_ah_attr *ah_attr);
 int ib_destroy_ah(struct ib_ah *ah);
 
 /**
+ * ib_create_srq - Creates a SRQ associated with the specified protection
+ *   domain.
+ * @pd: The protection domain associated with the SRQ.
+ * @srq_init_attr: A list of initial attributes required to create the SRQ.
+ *
+ * srq_attr->max_wr and srq_attr->max_sge are read the determine the
+ * requested size of the SRQ, and set to the actual values allocated
+ * on return.  If ib_create_srq() succeeds, then max_wr and max_sge
+ * will always be at least as large as the requested values.
+ */
+struct ib_srq *ib_create_srq(struct ib_pd *pd,
+                             struct ib_srq_init_attr *srq_init_attr);
+
+/**
+ * ib_modify_srq - Modifies the attributes for the specified SRQ.
+ * @srq: The SRQ to modify.
+ * @srq_attr: On input, specifies the SRQ attributes to modify.  On output,
+ *   the current values of selected SRQ attributes are returned.
+ * @srq_attr_mask: A bit-mask used to specify which attributes of the SRQ
+ *   are being modified.
+ *
+ * The mask may contain IB_SRQ_MAX_WR to resize the SRQ and/or
+ * IB_SRQ_LIMIT to set the SRQ's limit and request notification when
+ * the number of receives queued drops below the limit.
+ */
+int ib_modify_srq(struct ib_srq *srq,
+                  struct ib_srq_attr *srq_attr,
+                  enum ib_srq_attr_mask srq_attr_mask);
+
+/**
+ * ib_query_srq - Returns the attribute list and current values for the
+ *   specified SRQ.
+ * @srq: The SRQ to query.
+ * @srq_attr: The attributes of the specified SRQ.
+ */
+int ib_query_srq(struct ib_srq *srq,
+                 struct ib_srq_attr *srq_attr);
+
+/**
+ * ib_destroy_srq - Destroys the specified SRQ.
+ * @srq: The SRQ to destroy.
+ */
+int ib_destroy_srq(struct ib_srq *srq);
+
+/**
+ * ib_post_srq_recv - Posts a list of work requests to the specified SRQ.
+ * @srq: The SRQ to post the work request on.
+ * @recv_wr: A list of work requests to post on the receive queue.
+ * @bad_recv_wr: On an immediate failure, this parameter will reference
+ *   the work request that failed to be posted on the QP.
+ */
+static inline int ib_post_srq_recv(struct ib_srq *srq,
+                                   struct ib_recv_wr *recv_wr,
+                                   struct ib_recv_wr **bad_recv_wr)
+{
+        return srq->device->post_srq_recv(srq, recv_wr, bad_recv_wr);
+}
+
+/**
  * ib_create_qp - Creates a QP associated with the specified protection
  *   domain.
  * @pd: The protection domain associated with the QP.