RDMA/bnxt_re: Add resize_cq support

Add resize_cq verb support for user space CQs. Resize operation for
kernel CQs are not supported now.

Driver should free the current CQ only after user library polls
for all the completions and switch to new CQ. So after the resize_cq
is returned from the driver, user library polls for existing completions
and store it as temporary data. Once library reaps all completions in the
current CQ, it invokes the ibv_cmd_poll_cq to inform the driver about
the resize_cq completion. Adding a check for user CQs in driver's
poll_cq and complete the resize operation for user CQs.
Updating uverbs_cmd_mask with poll_cq to support this.

Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1678868215-23626-1-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

5 files changed, 163 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.c b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
index 989edc789633..e86afecfbe46 100644
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.c
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
@@ -2912,6 +2912,106 @@ fail:
 	return rc;
 }
 
+static void bnxt_re_resize_cq_complete(struct bnxt_re_cq *cq)
+{
+	struct bnxt_re_dev *rdev = cq->rdev;
+
+	bnxt_qplib_resize_cq_complete(&rdev->qplib_res, &cq->qplib_cq);
+
+	cq->qplib_cq.max_wqe = cq->resize_cqe;
+	if (cq->resize_umem) {
+		ib_umem_release(cq->umem);
+		cq->umem = cq->resize_umem;
+		cq->resize_umem = NULL;
+		cq->resize_cqe = 0;
+	}
+}
+
+int bnxt_re_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata)
+{
+	struct bnxt_qplib_sg_info sg_info = {};
+	struct bnxt_qplib_dpi *orig_dpi = NULL;
+	struct bnxt_qplib_dev_attr *dev_attr;
+	struct bnxt_re_ucontext *uctx = NULL;
+	struct bnxt_re_resize_cq_req req;
+	struct bnxt_re_dev *rdev;
+	struct bnxt_re_cq *cq;
+	int rc, entries;
+
+	cq =  container_of(ibcq, struct bnxt_re_cq, ib_cq);
+	rdev = cq->rdev;
+	dev_attr = &rdev->dev_attr;
+	if (!ibcq->uobject) {
+		ibdev_err(&rdev->ibdev, "Kernel CQ Resize not supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (cq->resize_umem) {
+		ibdev_err(&rdev->ibdev, "Resize CQ %#x failed - Busy",
+			  cq->qplib_cq.id);
+		return -EBUSY;
+	}
+
+	/* Check the requested cq depth out of supported depth */
+	if (cqe < 1 || cqe > dev_attr->max_cq_wqes) {
+		ibdev_err(&rdev->ibdev, "Resize CQ %#x failed - out of range cqe %d",
+			  cq->qplib_cq.id, cqe);
+		return -EINVAL;
+	}
+
+	entries = roundup_pow_of_two(cqe + 1);
+	if (entries > dev_attr->max_cq_wqes + 1)
+		entries = dev_attr->max_cq_wqes + 1;
+
+	uctx = rdma_udata_to_drv_context(udata, struct bnxt_re_ucontext,
+					 ib_uctx);
+	/* uverbs consumer */
+	if (ib_copy_from_udata(&req, udata, sizeof(req))) {
+		rc = -EFAULT;
+		goto fail;
+	}
+
+	cq->resize_umem = ib_umem_get(&rdev->ibdev, req.cq_va,
+				      entries * sizeof(struct cq_base),
+				      IB_ACCESS_LOCAL_WRITE);
+	if (IS_ERR(cq->resize_umem)) {
+		rc = PTR_ERR(cq->resize_umem);
+		cq->resize_umem = NULL;
+		ibdev_err(&rdev->ibdev, "%s: ib_umem_get failed! rc = %d\n",
+			  __func__, rc);
+		goto fail;
+	}
+	cq->resize_cqe = entries;
+	memcpy(&sg_info, &cq->qplib_cq.sg_info, sizeof(sg_info));
+	orig_dpi = cq->qplib_cq.dpi;
+
+	cq->qplib_cq.sg_info.umem = cq->resize_umem;
+	cq->qplib_cq.sg_info.pgsize = PAGE_SIZE;
+	cq->qplib_cq.sg_info.pgshft = PAGE_SHIFT;
+	cq->qplib_cq.dpi = &uctx->dpi;
+
+	rc = bnxt_qplib_resize_cq(&rdev->qplib_res, &cq->qplib_cq, entries);
+	if (rc) {
+		ibdev_err(&rdev->ibdev, "Resize HW CQ %#x failed!",
+			  cq->qplib_cq.id);
+		goto fail;
+	}
+
+	cq->ib_cq.cqe = cq->resize_cqe;
+
+	return 0;
+
+fail:
+	if (cq->resize_umem) {
+		ib_umem_release(cq->resize_umem);
+		cq->resize_umem = NULL;
+		cq->resize_cqe = 0;
+		memcpy(&cq->qplib_cq.sg_info, &sg_info, sizeof(sg_info));
+		cq->qplib_cq.dpi = orig_dpi;
+	}
+	return rc;
+}
+
 static u8 __req_to_ib_wc_status(u8 qstatus)
 {
 	switch (qstatus) {
@@ -3425,6 +3525,15 @@ int bnxt_re_poll_cq(struct ib_cq *ib_cq, int num_entries, struct ib_wc *wc)
 	struct bnxt_re_sqp_entries *sqp_entry = NULL;
 	unsigned long flags;
 
+	/* User CQ; the only processing we do is to
+	 * complete any pending CQ resize operation.
+	 */
+	if (cq->umem) {
+		if (cq->resize_umem)
+			bnxt_re_resize_cq_complete(cq);
+		return 0;
+	}
+
 	spin_lock_irqsave(&cq->cq_lock, flags);
 	budget = min_t(u32, num_entries, cq->max_cql);
 	num_entries = budget;
diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.h b/drivers/infiniband/hw/bnxt_re/ib_verbs.h
index 94326267f9bb..31f7e34040f7 100644
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.h
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.h
@@ -104,6 +104,8 @@ struct bnxt_re_cq {
 #define MAX_CQL_PER_POLL	1024
 	u32			max_cql;
 	struct ib_umem		*umem;
+	struct ib_umem		*resize_umem;
+	int			resize_cqe;
 };
 
 struct bnxt_re_mr {
@@ -191,6 +193,7 @@ int bnxt_re_post_recv(struct ib_qp *qp, const struct ib_recv_wr *recv_wr,
 		      const struct ib_recv_wr **bad_recv_wr);
 int bnxt_re_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		      struct ib_udata *udata);
+int bnxt_re_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata);
 int bnxt_re_destroy_cq(struct ib_cq *cq, struct ib_udata *udata);
 int bnxt_re_poll_cq(struct ib_cq *cq, int num_entries, struct ib_wc *wc);
 int bnxt_re_req_notify_cq(struct ib_cq *cq, enum ib_cq_notify_flags flags);
diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c
index c5867e78f231..48bbba7df22e 100644
--- a/drivers/infiniband/hw/bnxt_re/main.c
+++ b/drivers/infiniband/hw/bnxt_re/main.c
@@ -553,6 +553,7 @@ static const struct ib_device_ops bnxt_re_dev_ops = {
 	.query_srq = bnxt_re_query_srq,
 	.reg_user_mr = bnxt_re_reg_user_mr,
 	.req_notify_cq = bnxt_re_req_notify_cq,
+	.resize_cq = bnxt_re_resize_cq,
 	INIT_RDMA_OBJ_SIZE(ib_ah, bnxt_re_ah, ib_ah),
 	INIT_RDMA_OBJ_SIZE(ib_cq, bnxt_re_cq, ib_cq),
 	INIT_RDMA_OBJ_SIZE(ib_pd, bnxt_re_pd, ib_pd),
@@ -584,6 +585,7 @@ static int bnxt_re_register_ib(struct bnxt_re_dev *rdev)
 		return ret;
 
 	dma_set_max_seg_size(&rdev->en_dev->pdev->dev, UINT_MAX);
+	ibdev->uverbs_cmd_mask |= BIT_ULL(IB_USER_VERBS_CMD_POLL_CQ);
 	return ib_register_device(ibdev, "bnxt_re%d", &rdev->en_dev->pdev->dev);
 }
 
diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.c b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
index 96e581ced50e..1d769a3106f6 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
@@ -2100,6 +2100,50 @@ exit:
 	return rc;
 }
 
+void bnxt_qplib_resize_cq_complete(struct bnxt_qplib_res *res,
+				   struct bnxt_qplib_cq *cq)
+{
+	bnxt_qplib_free_hwq(res, &cq->hwq);
+	memcpy(&cq->hwq, &cq->resize_hwq, sizeof(cq->hwq));
+}
+
+int bnxt_qplib_resize_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq,
+			 int new_cqes)
+{
+	struct bnxt_qplib_hwq_attr hwq_attr = {};
+	struct bnxt_qplib_rcfw *rcfw = res->rcfw;
+	struct creq_resize_cq_resp resp = {};
+	struct cmdq_resize_cq req = {};
+	struct bnxt_qplib_pbl *pbl;
+	u32 pg_sz, lvl, new_sz;
+	u16 cmd_flags = 0;
+	int rc;
+
+	RCFW_CMD_PREP(req, RESIZE_CQ, cmd_flags);
+	hwq_attr.sginfo = &cq->sg_info;
+	hwq_attr.res = res;
+	hwq_attr.depth = new_cqes;
+	hwq_attr.stride = sizeof(struct cq_base);
+	hwq_attr.type = HWQ_TYPE_QUEUE;
+	rc = bnxt_qplib_alloc_init_hwq(&cq->resize_hwq, &hwq_attr);
+	if (rc)
+		return rc;
+
+	req.cq_cid = cpu_to_le32(cq->id);
+	pbl = &cq->resize_hwq.pbl[PBL_LVL_0];
+	pg_sz = bnxt_qplib_base_pg_size(&cq->resize_hwq);
+	lvl = (cq->resize_hwq.level << CMDQ_RESIZE_CQ_LVL_SFT) &
+				       CMDQ_RESIZE_CQ_LVL_MASK;
+	new_sz = (new_cqes << CMDQ_RESIZE_CQ_NEW_CQ_SIZE_SFT) &
+		  CMDQ_RESIZE_CQ_NEW_CQ_SIZE_MASK;
+	req.new_cq_size_pg_size_lvl = cpu_to_le32(new_sz | pg_sz | lvl);
+	req.new_pbl = cpu_to_le64(pbl->pg_map_arr[0]);
+
+	rc = bnxt_qplib_rcfw_send_message(rcfw, (void *)&req,
+					  (void *)&resp, NULL, 0);
+	return rc;
+}
+
 int bnxt_qplib_destroy_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq)
 {
 	struct bnxt_qplib_rcfw *rcfw = res->rcfw;
diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.h b/drivers/infiniband/hw/bnxt_re/qplib_fp.h
index 037501952543..d74d5ead2e32 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.h
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.h
@@ -400,6 +400,7 @@ struct bnxt_qplib_cq {
 	u16				count;
 	u16				period;
 	struct bnxt_qplib_hwq		hwq;
+	struct bnxt_qplib_hwq		resize_hwq;
 	u32				cnq_hw_ring_id;
 	struct bnxt_qplib_nq		*nq;
 	bool				resize_in_progress;
@@ -532,6 +533,10 @@ void bnxt_qplib_post_recv_db(struct bnxt_qplib_qp *qp);
 int bnxt_qplib_post_recv(struct bnxt_qplib_qp *qp,
 			 struct bnxt_qplib_swqe *wqe);
 int bnxt_qplib_create_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq);
+int bnxt_qplib_resize_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq,
+			 int new_cqes);
+void bnxt_qplib_resize_cq_complete(struct bnxt_qplib_res *res,
+				   struct bnxt_qplib_cq *cq);
 int bnxt_qplib_destroy_cq(struct bnxt_qplib_res *res, struct bnxt_qplib_cq *cq);
 int bnxt_qplib_poll_cq(struct bnxt_qplib_cq *cq, struct bnxt_qplib_cqe *cqe,
 		       int num, struct bnxt_qplib_qp **qp);