[PATCH rdma-next v4 08/16] RDMA/efa: Use ib_umem_get_cq_buf() for user CQ buffer

[Jiri Pirko <jiri@resnulli.us>]

From: Jiri Pirko <jiri@nvidia.com>

Pin the user CQ buffer with ib_umem_get_cq_buf() and take
ownership of the umem in the driver. Fall back to the
existing kernel-DMA path on NULL.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
v2->v3:
- used ib_umem_get_cq_buf() to get umem, stored in efa_cq->umem
- replaced ib_umem_release_non_listed() with ib_umem_release()
- added release to efa_destroy_cq() and new error path
---
 drivers/infiniband/hw/efa/efa_verbs.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/drivers/infiniband/hw/efa/efa_verbs.c b/drivers/infiniband/hw/efa/efa_verbs.c
index e103d1654a69..aebae70b882c 100644
--- a/drivers/infiniband/hw/efa/efa_verbs.c
+++ b/drivers/infiniband/hw/efa/efa_verbs.c
@@ -1072,6 +1072,7 @@ int efa_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata)
 
 	if (cq->cpu_addr)
 		efa_free_mapped(dev, cq->cpu_addr, cq->dma_addr, cq->size, DMA_FROM_DEVICE);
+	ib_umem_release(cq->umem);
 	return 0;
 }
 
@@ -1124,6 +1125,7 @@ int efa_create_user_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	struct efa_ibv_create_cq cmd;
 	struct efa_cq *cq = to_ecq(ibcq);
 	int entries = attr->cqe;
+	struct ib_umem *umem;
 	bool set_src_addr;
 	int err;
 
@@ -1172,26 +1174,29 @@ int efa_create_user_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	cq->ucontext = ucontext;
 	cq->size = PAGE_ALIGN(cmd.cq_entry_size * entries * cmd.num_sub_cqs);
 
-	if (ibcq->umem) {
-		if (ibcq->umem->length < cq->size) {
-			ibdev_dbg(&dev->ibdev, "External memory too small\n");
-			err = -EINVAL;
-			goto err_out;
-		}
+	umem = ib_umem_get_cq_buf(ibcq->device, udata, cq->size,
+				  IB_ACCESS_LOCAL_WRITE);
+	if (IS_ERR(umem)) {
+		err = PTR_ERR(umem);
+		goto err_out;
+	}
+
+	cq->umem = umem;
 
-		if (!ib_umem_is_contiguous(ibcq->umem)) {
+	if (umem) {
+		if (!ib_umem_is_contiguous(umem)) {
 			ibdev_dbg(&dev->ibdev, "Non contiguous CQ unsupported\n");
 			err = -EINVAL;
-			goto err_out;
+			goto err_release_umem;
 		}
 
-		cq->dma_addr = ib_umem_start_dma_addr(ibcq->umem);
+		cq->dma_addr = ib_umem_start_dma_addr(umem);
 	} else {
 		cq->cpu_addr = efa_zalloc_mapped(dev, &cq->dma_addr, cq->size,
 						 DMA_FROM_DEVICE);
 		if (!cq->cpu_addr) {
 			err = -ENOMEM;
-			goto err_out;
+			goto err_release_umem;
 		}
 	}
 
@@ -1262,6 +1267,8 @@ int efa_create_user_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	if (cq->cpu_addr)
 		efa_free_mapped(dev, cq->cpu_addr, cq->dma_addr, cq->size,
 				DMA_FROM_DEVICE);
+err_release_umem:
+	ib_umem_release(cq->umem);
 err_out:
 	atomic64_inc(&dev->stats.create_cq_err);
 	return err;
-- 
2.53.0