[PATCH for-next 2/4] RDMA/erdma: Support non-contiguous kernel CQ buffers

Cheng Xu <[email protected]>
Newsgroups org.kernel.vger.linux-rdma
Message-ID <[email protected]> 
A single coherent allocation for a kernel CQ can fail when memory is
fragmented.

Use page-sized coherent buffers and describe them with the existing MTT.
Keep the userspace CQ path and doorbell allocation unchanged.

Signed-off-by: Cheng Xu <[email protected]>
---
 drivers/infiniband/hw/erdma/erdma_cq.c    | 15 ++---
 drivers/infiniband/hw/erdma/erdma_verbs.c | 77 +++++++++--------------
 drivers/infiniband/hw/erdma/erdma_verbs.h |  3 +-
 3 files changed, 38 insertions(+), 57 deletions(-)

diff --git a/drivers/infiniband/hw/erdma/erdma_cq.c b/drivers/infiniband/hw/erdma/erdma_cq.c
index 4cc0254b0ab5..7cfb067c0b40 100644
--- a/drivers/infiniband/hw/erdma/erdma_cq.c
+++ b/drivers/infiniband/hw/erdma/erdma_cq.c
@@ -8,8 +8,8 @@
 
 static void *get_next_valid_cqe(struct erdma_cq *cq)
 {
-	__be32 *cqe = get_queue_entry(cq->kern_cq.qbuf, cq->kern_cq.ci,
-				      cq->depth, CQE_SHIFT);
+	__be32 *cqe = erdma_kmem_get_entry(&cq->kern_cq.qbuf_mem,
+					 cq->kern_cq.ci, cq->depth, CQE_SHIFT);
 	u32 owner = FIELD_GET(ERDMA_CQE_HDR_OWNER_MASK,
 			      be32_to_cpu(READ_ONCE(*cqe)));
 
@@ -242,15 +242,16 @@ void erdma_remove_cqes_of_qp(struct ib_cq *ibcq, u32 qpn)
 
 	while (ncqe > 0) {
 		cur_cq_ci = prev_cq_ci + ncqe - 1;
-		cqe = get_queue_entry(cq->kern_cq.qbuf, cur_cq_ci, cq->depth,
-				      CQE_SHIFT);
+		cqe = erdma_kmem_get_entry(&cq->kern_cq.qbuf_mem, cur_cq_ci,
+					   cq->depth, CQE_SHIFT);
 
 		if (be32_to_cpu(cqe->qpn) == qpn) {
 			++nqp_cqe;
 		} else if (nqp_cqe) {
-			dst_cqe = get_queue_entry(cq->kern_cq.qbuf,
-						  cur_cq_ci + nqp_cqe,
-						  cq->depth, CQE_SHIFT);
+			dst_cqe =
+				erdma_kmem_get_entry(&cq->kern_cq.qbuf_mem,
+						     cur_cq_ci + nqp_cqe,
+						     cq->depth, CQE_SHIFT);
 			owner = FIELD_GET(ERDMA_CQE_HDR_OWNER_MASK,
 					  be32_to_cpu(dst_cqe->hdr));
 			cqe->hdr = cpu_to_be32(
diff --git a/drivers/infiniband/hw/erdma/erdma_verbs.c b/drivers/infiniband/hw/erdma/erdma_verbs.c
index 918abc9377ab..49bf3b2a60b9 100644
--- a/drivers/infiniband/hw/erdma/erdma_verbs.c
+++ b/drivers/infiniband/hw/erdma/erdma_verbs.c
@@ -177,7 +177,6 @@ static int create_cq_cmd(struct erdma_ucontext *uctx, struct erdma_cq *cq)
 	struct erdma_dev *dev = to_edev(cq->ibcq.device);
 	struct erdma_cmdq_create_cq_req req;
 	struct erdma_mem *mem;
-	u32 page_size;
 
 	erdma_cmdq_build_reqhdr(&req.hdr, CMDQ_SUBMOD_RDMA,
 				CMDQ_OPCODE_CREATE_CQ);
@@ -187,48 +186,35 @@ static int create_cq_cmd(struct erdma_ucontext *uctx, struct erdma_cq *cq)
 	req.cfg1 = FIELD_PREP(ERDMA_CMD_CREATE_CQ_EQN_MASK, cq->assoc_eqn);
 
 	if (rdma_is_kernel_res(&cq->ibcq.res)) {
-		page_size = SZ_32M;
-		req.cfg0 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_PAGESIZE_MASK,
-				       ilog2(page_size) - ERDMA_HW_PAGE_SHIFT);
-		req.qbuf_addr_l = lower_32_bits(cq->kern_cq.qbuf_dma_addr);
-		req.qbuf_addr_h = upper_32_bits(cq->kern_cq.qbuf_dma_addr);
-
-		req.cfg1 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_CNT_MASK, 1) |
-			    FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_LEVEL_MASK,
-				       ERDMA_MR_MTT_0LEVEL);
-
-		req.first_page_offset = 0;
+		mem = &cq->kern_cq.qbuf_mem;
 		req.cq_dbrec_dma = cq->kern_cq.dbrec_dma;
 	} else {
 		mem = &cq->user_cq.qbuf_mem;
-		req.cfg0 |=
-			FIELD_PREP(ERDMA_CMD_CREATE_CQ_PAGESIZE_MASK,
-				   ilog2(mem->page_size) - ERDMA_HW_PAGE_SHIFT);
-		if (mem->mtt_nents == 1) {
-			req.qbuf_addr_l = lower_32_bits(mem->mtt->buf[0]);
-			req.qbuf_addr_h = upper_32_bits(mem->mtt->buf[0]);
-			req.cfg1 |=
-				FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_LEVEL_MASK,
-					   ERDMA_MR_MTT_0LEVEL);
-		} else {
-			req.qbuf_addr_l = lower_32_bits(mem->mtt->buf_dma);
-			req.qbuf_addr_h = upper_32_bits(mem->mtt->buf_dma);
-			req.cfg1 |=
-				FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_LEVEL_MASK,
-					   ERDMA_MR_MTT_1LEVEL);
-		}
-		req.cfg1 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_CNT_MASK,
-				       mem->mtt_nents);
-
-		req.first_page_offset = mem->page_offset;
 		req.cq_dbrec_dma = cq->user_cq.dbrec_dma;
+	}
 
-		if (uctx->ext_db.enable) {
-			req.cfg1 |= FIELD_PREP(
-				ERDMA_CMD_CREATE_CQ_MTT_DB_CFG_MASK, 1);
-			req.cfg2 = FIELD_PREP(ERDMA_CMD_CREATE_CQ_DB_CFG_MASK,
-					      uctx->ext_db.cdb_off);
-		}
+	req.cfg0 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_PAGESIZE_MASK,
+			       ilog2(mem->page_size) - ERDMA_HW_PAGE_SHIFT);
+	if (mem->mtt_nents == 1) {
+		req.qbuf_addr_l = lower_32_bits(mem->mtt->buf[0]);
+		req.qbuf_addr_h = upper_32_bits(mem->mtt->buf[0]);
+		req.cfg1 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_LEVEL_MASK,
+				       ERDMA_MR_MTT_0LEVEL);
+	} else {
+		req.qbuf_addr_l = lower_32_bits(mem->mtt->buf_dma);
+		req.qbuf_addr_h = upper_32_bits(mem->mtt->buf_dma);
+		req.cfg1 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_LEVEL_MASK,
+				       ERDMA_MR_MTT_1LEVEL);
+	}
+	req.cfg1 |= FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_CNT_MASK,
+			       mem->mtt_nents);
+	req.first_page_offset = mem->page_offset;
+
+	if (uctx && uctx->ext_db.enable) {
+		req.cfg1 |=
+			FIELD_PREP(ERDMA_CMD_CREATE_CQ_MTT_DB_CFG_MASK, 1);
+		req.cfg2 = FIELD_PREP(ERDMA_CMD_CREATE_CQ_DB_CFG_MASK,
+				      uctx->ext_db.cdb_off);
 	}
 
 	return erdma_post_cmd_wait(&dev->cmdq, &req, sizeof(req), NULL, NULL,
@@ -1392,8 +1378,7 @@ int erdma_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata)
 	wait_for_completion(&cq->free);
 
 	if (rdma_is_kernel_res(&cq->ibcq.res)) {
-		dma_free_coherent(&dev->pdev->dev, cq->depth << CQE_SHIFT,
-				  cq->kern_cq.qbuf, cq->kern_cq.qbuf_dma_addr);
+		put_mtt_entries(dev, &cq->kern_cq.qbuf_mem);
 		dma_pool_free(dev->db_pool, cq->kern_cq.dbrec,
 			      cq->kern_cq.dbrec_dma);
 	} else {
@@ -1991,10 +1976,8 @@ static int erdma_init_kernel_cq(struct erdma_cq *cq)
 {
 	struct erdma_dev *dev = to_edev(cq->ibcq.device);
 
-	cq->kern_cq.qbuf =
-		dma_alloc_coherent(&dev->pdev->dev, cq->depth << CQE_SHIFT,
-				   &cq->kern_cq.qbuf_dma_addr, GFP_KERNEL);
-	if (!cq->kern_cq.qbuf)
+	if (erdma_alloc_kmem(dev, &cq->kern_cq.qbuf_mem,
+			     cq->depth << CQE_SHIFT))
 		return -ENOMEM;
 
 	cq->kern_cq.dbrec = dma_pool_zalloc(dev->db_pool, GFP_KERNEL,
@@ -2009,8 +1992,7 @@ static int erdma_init_kernel_cq(struct erdma_cq *cq)
 	return 0;
 
 err_out:
-	dma_free_coherent(&dev->pdev->dev, cq->depth << CQE_SHIFT,
-			  cq->kern_cq.qbuf, cq->kern_cq.qbuf_dma_addr);
+	put_mtt_entries(dev, &cq->kern_cq.qbuf_mem);
 
 	return -ENOMEM;
 }
@@ -2077,8 +2059,7 @@ int erdma_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 		erdma_unmap_user_dbrecords(ctx, &cq->user_cq.user_dbr_page);
 		put_mtt_entries(dev, &cq->user_cq.qbuf_mem);
 	} else {
-		dma_free_coherent(&dev->pdev->dev, depth << CQE_SHIFT,
-				  cq->kern_cq.qbuf, cq->kern_cq.qbuf_dma_addr);
+		put_mtt_entries(dev, &cq->kern_cq.qbuf_mem);
 		dma_pool_free(dev->db_pool, cq->kern_cq.dbrec,
 			      cq->kern_cq.dbrec_dma);
 	}
diff --git a/drivers/infiniband/hw/erdma/erdma_verbs.h b/drivers/infiniband/hw/erdma/erdma_verbs.h
index eb7318cf7a52..5056d60357db 100644
--- a/drivers/infiniband/hw/erdma/erdma_verbs.h
+++ b/drivers/infiniband/hw/erdma/erdma_verbs.h
@@ -352,8 +352,7 @@ struct erdma_qp {
 };
 
 struct erdma_kcq_info {
-	void *qbuf;
-	dma_addr_t qbuf_dma_addr;
+	struct erdma_mem qbuf_mem;
 	u32 ci;
 	u32 cmdsn;
 	u32 notify_cnt;
-- 
2.31.1
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.