RDMA/mana_ib: UD/GSI work requests

Implement post send and post recv for UD/GSI QPs.
Add information about posted requests into shadow queues.

Co-developed-by: Shiraz Saleem <shirazsaleem@microsoft.com>
Signed-off-by: Shiraz Saleem <shirazsaleem@microsoft.com>
Signed-off-by: Konstantin Taranov <kotaranov@microsoft.com>
Link: https://patch.msgid.link/1737394039-28772-10-git-send-email-kotaranov@linux.microsoft.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/hw/mana/Makefile

@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_MANA_INFINIBAND) += mana_ib.o
 
-mana_ib-y := device.o main.o wq.o qp.o cq.o mr.o ah.o
+mana_ib-y := device.o main.o wq.o qp.o cq.o mr.o ah.o wr.o

drivers/infiniband/hw/mana/device.c

@@ -40,6 +40,8 @@ static const struct ib_device_ops mana_ib_dev_ops = {
 	.mmap = mana_ib_mmap,
 	.modify_qp = mana_ib_modify_qp,
 	.modify_wq = mana_ib_modify_wq,
+	.post_recv = mana_ib_post_recv,
+	.post_send = mana_ib_post_send,
 	.query_device = mana_ib_query_device,
 	.query_gid = mana_ib_query_gid,
 	.query_pkey = mana_ib_query_pkey,

drivers/infiniband/hw/mana/mana_ib.h

@@ -14,6 +14,7 @@
 #include <linux/dmapool.h>
 
 #include <net/mana/mana.h>
+#include "shadow_queue.h"
 
 #define PAGE_SZ_BM                                                             \
 	(SZ_4K | SZ_8K | SZ_16K | SZ_32K | SZ_64K | SZ_128K | SZ_256K |        \
@@ -165,6 +166,9 @@ struct mana_ib_qp {
 	/* The port on the IB device, starting with 1 */
 	u32 port;
 
+	struct shadow_queue shadow_rq;
+	struct shadow_queue shadow_sq;
+
 	refcount_t		refcount;
 	struct completion	free;
 };
@@ -404,6 +408,30 @@ struct mana_rnic_set_qp_state_resp {
 	struct gdma_resp_hdr hdr;
 }; /* HW Data */
 
+enum WQE_OPCODE_TYPES {
+	WQE_TYPE_UD_SEND = 0,
+	WQE_TYPE_UD_RECV = 8,
+}; /* HW DATA */
+
+struct rdma_send_oob {
+	u32 wqe_type	: 5;
+	u32 fence	: 1;
+	u32 signaled	: 1;
+	u32 solicited	: 1;
+	u32 psn		: 24;
+
+	u32 ssn_or_rqpn	: 24;
+	u32 reserved1	: 8;
+	union {
+		struct {
+			u32 remote_qkey;
+			u32 immediate;
+			u32 reserved1;
+			u32 reserved2;
+		} ud_send;
+	};
+}; /* HW DATA */
+
 static inline struct gdma_context *mdev_to_gc(struct mana_ib_dev *mdev)
 {
 	return mdev->gdma_dev->gdma_context;
@@ -562,4 +590,9 @@ int mana_ib_gd_destroy_ud_qp(struct mana_ib_dev *mdev, struct mana_ib_qp *qp);
 int mana_ib_create_ah(struct ib_ah *ibah, struct rdma_ah_init_attr *init_attr,
 		      struct ib_udata *udata);
 int mana_ib_destroy_ah(struct ib_ah *ah, u32 flags);
+
+int mana_ib_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr);
+int mana_ib_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+		      const struct ib_send_wr **bad_wr);
 #endif

drivers/infiniband/hw/mana/qp.c

@@ -562,10 +562,23 @@ static int mana_ib_create_ud_qp(struct ib_qp *ibqp, struct ib_pd *ibpd,
 	}
 	doorbell = gc->mana_ib.doorbell;
 
+	err = create_shadow_queue(&qp->shadow_rq, attr->cap.max_recv_wr,
+				  sizeof(struct ud_rq_shadow_wqe));
+	if (err) {
+		ibdev_err(&mdev->ib_dev, "Failed to create shadow rq err %d\n", err);
+		goto destroy_queues;
+	}
+	err = create_shadow_queue(&qp->shadow_sq, attr->cap.max_send_wr,
+				  sizeof(struct ud_sq_shadow_wqe));
+	if (err) {
+		ibdev_err(&mdev->ib_dev, "Failed to create shadow sq err %d\n", err);
+		goto destroy_shadow_queues;
+	}
+
 	err = mana_ib_gd_create_ud_qp(mdev, qp, attr, doorbell, attr->qp_type);
 	if (err) {
 		ibdev_err(&mdev->ib_dev, "Failed to create ud qp  %d\n", err);
-		goto destroy_queues;
+		goto destroy_shadow_queues;
 	}
 	qp->ibqp.qp_num = qp->ud_qp.queues[MANA_UD_RECV_QUEUE].id;
 	qp->port = attr->port_num;
@@ -575,6 +588,9 @@ static int mana_ib_create_ud_qp(struct ib_qp *ibqp, struct ib_pd *ibpd,
 
 	return 0;
 
+destroy_shadow_queues:
+	destroy_shadow_queue(&qp->shadow_rq);
+	destroy_shadow_queue(&qp->shadow_sq);
 destroy_queues:
 	while (i-- > 0)
 		mana_ib_destroy_queue(mdev, &qp->ud_qp.queues[i]);
@@ -754,6 +770,9 @@ static int mana_ib_destroy_ud_qp(struct mana_ib_qp *qp, struct ib_udata *udata)
 		container_of(qp->ibqp.device, struct mana_ib_dev, ib_dev);
 	int i;
 
+	destroy_shadow_queue(&qp->shadow_rq);
+	destroy_shadow_queue(&qp->shadow_sq);
+
 	/* Ignore return code as there is not much we can do about it.
 	 * The error message is printed inside.
 	 */

drivers/infiniband/hw/mana/shadow_queue.h

@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2024, Microsoft Corporation. All rights reserved.
+ */
+
+#ifndef _MANA_SHADOW_QUEUE_H_
+#define _MANA_SHADOW_QUEUE_H_
+
+struct shadow_wqe_header {
+	u16 opcode;
+	u16 error_code;
+	u32 posted_wqe_size;
+	u64 wr_id;
+};
+
+struct ud_rq_shadow_wqe {
+	struct shadow_wqe_header header;
+	u32 byte_len;
+	u32 src_qpn;
+};
+
+struct ud_sq_shadow_wqe {
+	struct shadow_wqe_header header;
+};
+
+struct shadow_queue {
+	/* Unmasked producer index, Incremented on wqe posting */
+	u64 prod_idx;
+	/* Unmasked consumer index, Incremented on cq polling */
+	u64 cons_idx;
+	/* Unmasked index of next-to-complete (from HW) shadow WQE */
+	u64 next_to_complete_idx;
+	/* queue size in wqes */
+	u32 length;
+	/* distance between elements in bytes */
+	u32 stride;
+	/* ring buffer holding wqes */
+	void *buffer;
+};
+
+static inline int create_shadow_queue(struct shadow_queue *queue, uint32_t length, uint32_t stride)
+{
+	queue->buffer = kvmalloc(length * stride, GFP_KERNEL);
+	if (!queue->buffer)
+		return -ENOMEM;
+
+	queue->length = length;
+	queue->stride = stride;
+
+	return 0;
+}
+
+static inline void destroy_shadow_queue(struct shadow_queue *queue)
+{
+	kvfree(queue->buffer);
+}
+
+static inline bool shadow_queue_full(struct shadow_queue *queue)
+{
+	return (queue->prod_idx - queue->cons_idx) >= queue->length;
+}
+
+static inline bool shadow_queue_empty(struct shadow_queue *queue)
+{
+	return queue->prod_idx == queue->cons_idx;
+}
+
+static inline void *
+shadow_queue_get_element(const struct shadow_queue *queue, u64 unmasked_index)
+{
+	u32 index = unmasked_index % queue->length;
+
+	return ((u8 *)queue->buffer + index * queue->stride);
+}
+
+static inline void *
+shadow_queue_producer_entry(struct shadow_queue *queue)
+{
+	return shadow_queue_get_element(queue, queue->prod_idx);
+}
+
+static inline void *
+shadow_queue_get_next_to_consume(const struct shadow_queue *queue)
+{
+	if (queue->cons_idx == queue->next_to_complete_idx)
+		return NULL;
+
+	return shadow_queue_get_element(queue, queue->cons_idx);
+}
+
+static inline void *
+shadow_queue_get_next_to_complete(struct shadow_queue *queue)
+{
+	if (queue->next_to_complete_idx == queue->prod_idx)
+		return NULL;
+
+	return shadow_queue_get_element(queue, queue->next_to_complete_idx);
+}
+
+static inline void shadow_queue_advance_producer(struct shadow_queue *queue)
+{
+	queue->prod_idx++;
+}
+
+static inline void shadow_queue_advance_consumer(struct shadow_queue *queue)
+{
+	queue->cons_idx++;
+}
+
+static inline void shadow_queue_advance_next_to_complete(struct shadow_queue *queue)
+{
+	queue->next_to_complete_idx++;
+}
+
+#endif