IB/hfi1: Move receive work queue struct into uapi directory

The rvt_rwqe and rvt_rwq struct elements are shared between rdmavt and the
providers but are not in uapi directory.  As per the comment in
https://marc.info/?l=linux-rdma&m=152296522708522&w=2, The hfi1 driver and
the rdma core driver are not using shared structures in the uapi
directory.

Move rvt_rwqe and rvt_rwq struct into rvt-abi.h header in uapi directory.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Kamenee Arumugam <kamenee.arumugam@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 111 insertions, 41 deletions

diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
index 0d804a58f954..1384060f175d 100644
--- a/drivers/infiniband/sw/rdmavt/qp.c
+++ b/drivers/infiniband/sw/rdmavt/qp.c
@@ -803,6 +803,46 @@ static void rvt_remove_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp)
 }
 
 /**
+ * rvt_alloc_rq - allocate memory for user or kernel buffer
+ * @rq: receive queue data structure
+ * @size: number of request queue entries
+ * @node: The NUMA node
+ * @udata: True if user data is available or not false
+ *
+ * Return: If memory allocation failed, return -ENONEM
+ * This function is used by both shared receive
+ * queues and non-shared receive queues to allocate
+ * memory.
+ */
+int rvt_alloc_rq(struct rvt_rq *rq, u32 size, int node,
+		 struct ib_udata *udata)
+{
+	if (udata) {
+		rq->wq = vmalloc_user(sizeof(struct rvt_rwq) + size);
+		if (!rq->wq)
+			goto bail;
+		/* need kwq with no buffers */
+		rq->kwq = kzalloc_node(sizeof(*rq->kwq), GFP_KERNEL, node);
+		if (!rq->kwq)
+			goto bail;
+		rq->kwq->curr_wq = rq->wq->wq;
+	} else {
+		/* need kwq with buffers */
+		rq->kwq =
+			vzalloc_node(sizeof(struct rvt_krwq) + size, node);
+		if (!rq->kwq)
+			goto bail;
+		rq->kwq->curr_wq = rq->kwq->wq;
+	}
+
+	spin_lock_init(&rq->lock);
+	return 0;
+bail:
+	rvt_free_rq(rq);
+	return -ENOMEM;
+}
+
+/**
  * rvt_init_qp - initialize the QP state to the reset state
  * @qp: the QP to init or reinit
  * @type: the QP type
@@ -852,10 +892,6 @@ static void rvt_init_qp(struct rvt_dev_info *rdi, struct rvt_qp *qp,
 	qp->s_tail_ack_queue = 0;
 	qp->s_acked_ack_queue = 0;
 	qp->s_num_rd_atomic = 0;
-	if (qp->r_rq.wq) {
-		qp->r_rq.wq->head = 0;
-		qp->r_rq.wq->tail = 0;
-	}
 	qp->r_sge.num_sge = 0;
 	atomic_set(&qp->s_reserved_used, 0);
 }
@@ -1046,17 +1082,12 @@ struct ib_qp *rvt_create_qp(struct ib_pd *ibpd,
 			qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
 			sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
 				sizeof(struct rvt_rwqe);
-			if (udata)
-				qp->r_rq.wq = vmalloc_user(
-						sizeof(struct rvt_rwq) +
-						qp->r_rq.size * sz);
-			else
-				qp->r_rq.wq = vzalloc_node(
-						sizeof(struct rvt_rwq) +
-						qp->r_rq.size * sz,
-						rdi->dparms.node);
-			if (!qp->r_rq.wq)
+			err = rvt_alloc_rq(&qp->r_rq, qp->r_rq.size * sz,
+					   rdi->dparms.node, udata);
+			if (err) {
+				ret = ERR_PTR(err);
 				goto bail_driver_priv;
+			}
 		}
 
 		/*
@@ -1202,8 +1233,7 @@ bail_qpn:
 	rvt_free_qpn(&rdi->qp_dev->qpn_table, qp->ibqp.qp_num);
 
 bail_rq_wq:
-	if (!qp->ip)
-		vfree(qp->r_rq.wq);
+	rvt_free_rq(&qp->r_rq);
 
 bail_driver_priv:
 	rdi->driver_f.qp_priv_free(rdi, qp);
@@ -1269,19 +1299,26 @@ int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err)
 	}
 	wc.status = IB_WC_WR_FLUSH_ERR;
 
-	if (qp->r_rq.wq) {
-		struct rvt_rwq *wq;
+	if (qp->r_rq.kwq) {
 		u32 head;
 		u32 tail;
+		struct rvt_rwq *wq = NULL;
+		struct rvt_krwq *kwq = NULL;
 
 		spin_lock(&qp->r_rq.lock);
-
+		/* qp->ip used to validate if there is a  user buffer mmaped */
+		if (qp->ip) {
+			wq = qp->r_rq.wq;
+			head = RDMA_READ_UAPI_ATOMIC(wq->head);
+			tail = RDMA_READ_UAPI_ATOMIC(wq->tail);
+		} else {
+			kwq = qp->r_rq.kwq;
+			head = kwq->head;
+			tail = kwq->tail;
+		}
 		/* sanity check pointers before trusting them */
-		wq = qp->r_rq.wq;
-		head = wq->head;
 		if (head >= qp->r_rq.size)
 			head = 0;
-		tail = wq->tail;
 		if (tail >= qp->r_rq.size)
 			tail = 0;
 		while (tail != head) {
@@ -1290,8 +1327,10 @@ int rvt_error_qp(struct rvt_qp *qp, enum ib_wc_status err)
 				tail = 0;
 			rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc, 1);
 		}
-		wq->tail = tail;
-
+		if (qp->ip)
+			RDMA_WRITE_UAPI_ATOMIC(wq->tail, tail);
+		else
+			kwq->tail = tail;
 		spin_unlock(&qp->r_rq.lock);
 	} else if (qp->ibqp.event_handler) {
 		ret = 1;
@@ -1634,8 +1673,7 @@ int rvt_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
 
 	if (qp->ip)
 		kref_put(&qp->ip->ref, rvt_release_mmap_info);
-	else
-		vfree(qp->r_rq.wq);
+	kvfree(qp->r_rq.kwq);
 	rdi->driver_f.qp_priv_free(rdi, qp);
 	kfree(qp->s_ack_queue);
 	rdma_destroy_ah_attr(&qp->remote_ah_attr);
@@ -1721,7 +1759,7 @@ int rvt_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
 		  const struct ib_recv_wr **bad_wr)
 {
 	struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
-	struct rvt_rwq *wq = qp->r_rq.wq;
+	struct rvt_krwq *wq = qp->r_rq.kwq;
 	unsigned long flags;
 	int qp_err_flush = (ib_rvt_state_ops[qp->state] & RVT_FLUSH_RECV) &&
 				!qp->ibqp.srq;
@@ -1746,7 +1784,7 @@ int rvt_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
 		next = wq->head + 1;
 		if (next >= qp->r_rq.size)
 			next = 0;
-		if (next == wq->tail) {
+		if (next == READ_ONCE(wq->tail)) {
 			spin_unlock_irqrestore(&qp->r_rq.lock, flags);
 			*bad_wr = wr;
 			return -ENOMEM;
@@ -1770,8 +1808,7 @@ int rvt_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
 			 * Make sure queue entry is written
 			 * before the head index.
 			 */
-			smp_wmb();
-			wq->head = next;
+			smp_store_release(&wq->head, next);
 		}
 		spin_unlock_irqrestore(&qp->r_rq.lock, flags);
 	}
@@ -2141,7 +2178,7 @@ int rvt_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
 		      const struct ib_recv_wr **bad_wr)
 {
 	struct rvt_srq *srq = ibsrq_to_rvtsrq(ibsrq);
-	struct rvt_rwq *wq;
+	struct rvt_krwq *wq;
 	unsigned long flags;
 
 	for (; wr; wr = wr->next) {
@@ -2155,11 +2192,11 @@ int rvt_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
 		}
 
 		spin_lock_irqsave(&srq->rq.lock, flags);
-		wq = srq->rq.wq;
+		wq = srq->rq.kwq;
 		next = wq->head + 1;
 		if (next >= srq->rq.size)
 			next = 0;
-		if (next == wq->tail) {
+		if (next == READ_ONCE(wq->tail)) {
 			spin_unlock_irqrestore(&srq->rq.lock, flags);
 			*bad_wr = wr;
 			return -ENOMEM;
@@ -2171,8 +2208,7 @@ int rvt_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
 		for (i = 0; i < wr->num_sge; i++)
 			wqe->sg_list[i] = wr->sg_list[i];
 		/* Make sure queue entry is written before the head index. */
-		smp_wmb();
-		wq->head = next;
+		smp_store_release(&wq->head, next);
 		spin_unlock_irqrestore(&srq->rq.lock, flags);
 	}
 	return 0;
@@ -2230,6 +2266,25 @@ bad_lkey:
 }
 
 /**
+ * get_rvt_head - get head indices of the circular buffer
+ * @rq: data structure for request queue entry
+ * @ip: the QP
+ *
+ * Return - head index value
+ */
+static inline u32 get_rvt_head(struct rvt_rq *rq, void *ip)
+{
+	u32 head;
+
+	if (ip)
+		head = RDMA_READ_UAPI_ATOMIC(rq->wq->head);
+	else
+		head = rq->kwq->head;
+
+	return head;
+}
+
+/**
  * rvt_get_rwqe - copy the next RWQE into the QP's RWQE
  * @qp: the QP
  * @wr_id_only: update qp->r_wr_id only, not qp->r_sge
@@ -2243,21 +2298,26 @@ int rvt_get_rwqe(struct rvt_qp *qp, bool wr_id_only)
 {
 	unsigned long flags;
 	struct rvt_rq *rq;
+	struct rvt_krwq *kwq;
 	struct rvt_rwq *wq;
 	struct rvt_srq *srq;
 	struct rvt_rwqe *wqe;
 	void (*handler)(struct ib_event *, void *);
 	u32 tail;
+	u32 head;
 	int ret;
+	void *ip = NULL;
 
 	if (qp->ibqp.srq) {
 		srq = ibsrq_to_rvtsrq(qp->ibqp.srq);
 		handler = srq->ibsrq.event_handler;
 		rq = &srq->rq;
+		ip = srq->ip;
 	} else {
 		srq = NULL;
 		handler = NULL;
 		rq = &qp->r_rq;
+		ip = qp->ip;
 	}
 
 	spin_lock_irqsave(&rq->lock, flags);
@@ -2265,17 +2325,24 @@ int rvt_get_rwqe(struct rvt_qp *qp, bool wr_id_only)
 		ret = 0;
 		goto unlock;
 	}
+	if (ip) {
+		wq = rq->wq;
+		tail = RDMA_READ_UAPI_ATOMIC(wq->tail);
+	} else {
+		kwq = rq->kwq;
+		tail = kwq->tail;
+	}
 
-	wq = rq->wq;
-	tail = wq->tail;
 	/* Validate tail before using it since it is user writable. */
 	if (tail >= rq->size)
 		tail = 0;
-	if (unlikely(tail == wq->head)) {
+
+	head = get_rvt_head(rq, ip);
+	if (unlikely(tail == head)) {
 		ret = 0;
 		goto unlock;
 	}
-	/* Make sure entry is read after head index is read. */
+	/* Make sure entry is read after the count is read. */
 	smp_rmb();
 	wqe = rvt_get_rwqe_ptr(rq, tail);
 	/*
@@ -2285,7 +2352,10 @@ int rvt_get_rwqe(struct rvt_qp *qp, bool wr_id_only)
 	 */
 	if (++tail >= rq->size)
 		tail = 0;
-	wq->tail = tail;
+	if (ip)
+		RDMA_WRITE_UAPI_ATOMIC(wq->tail, tail);
+	else
+		kwq->tail = tail;
 	if (!wr_id_only && !init_sge(qp, wqe)) {
 		ret = -1;
 		goto unlock;
@@ -2301,7 +2371,7 @@ int rvt_get_rwqe(struct rvt_qp *qp, bool wr_id_only)
 		 * Validate head pointer value and compute
 		 * the number of remaining WQEs.
 		 */
-		n = wq->head;
+		n = get_rvt_head(rq, ip);
 		if (n >= rq->size)
 			n = 0;
 		if (n < tail)