[for-next PATCH 4/5] RDMA/rxe: refactor iova_to_vaddr

[Li Zhijian]

For IB_MR_TYPE_USER MR, iova_to_vaddr() will call kmap_local_page() to
map page.

Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
---
 drivers/infiniband/sw/rxe/rxe_loc.h   |  1 +
 drivers/infiniband/sw/rxe/rxe_mr.c    | 38 +++++++++++++++------------
 drivers/infiniband/sw/rxe/rxe_resp.c  |  1 +
 drivers/infiniband/sw/rxe/rxe_verbs.h |  5 +++-
 4 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
index c2a5c8814a48..22a8c44d39c8 100644
--- a/drivers/infiniband/sw/rxe/rxe_loc.h
+++ b/drivers/infiniband/sw/rxe/rxe_loc.h
@@ -73,6 +73,7 @@ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
 int copy_data(struct rxe_pd *pd, int access, struct rxe_dma_info *dma,
 	      void *addr, int length, enum rxe_mr_copy_dir dir);
 void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length);
+void rxe_unmap_vaddr(struct rxe_mr *mr, void *vaddr);
 struct rxe_mr *lookup_mr(struct rxe_pd *pd, int access, u32 key,
 			 enum rxe_mr_lookup_type type);
 int mr_check_range(struct rxe_mr *mr, u64 iova, size_t length);
diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
index a4e786b657b7..d26a4a33119c 100644
--- a/drivers/infiniband/sw/rxe/rxe_mr.c
+++ b/drivers/infiniband/sw/rxe/rxe_mr.c
@@ -120,9 +120,7 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
 	struct ib_umem		*umem;
 	struct sg_page_iter	sg_iter;
 	int			num_buf;
-	void			*vaddr;
 	int err;
-	int i;
 
 	umem = ib_umem_get(&rxe->ib_dev, start, length, access);
 	if (IS_ERR(umem)) {
@@ -159,18 +157,9 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
 				num_buf = 0;
 			}
 
-			vaddr = page_address(sg_page_iter_page(&sg_iter));
-			if (!vaddr) {
-				pr_warn("%s: Unable to get virtual address\n",
-						__func__);
-				err = -ENOMEM;
-				goto err_cleanup_map;
-			}
-
-			buf->addr = (uintptr_t)vaddr;
+			buf->page = sg_page_iter_page(&sg_iter);
 			num_buf++;
 			buf++;
-
 		}
 	}
 
@@ -182,10 +171,6 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
 
 	return 0;
 
-err_cleanup_map:
-	for (i = 0; i < mr->num_map; i++)
-		kfree(mr->map[i]);
-	kfree(mr->map);
 err_release_umem:
 	ib_umem_release(umem);
 err_out:
@@ -246,6 +231,12 @@ static void lookup_iova(struct rxe_mr *mr, u64 iova, int *m_out, int *n_out,
 	}
 }
 
+void rxe_unmap_vaddr(struct rxe_mr *mr, void *vaddr)
+{
+	if (mr->ibmr.type == IB_MR_TYPE_USER)
+		kunmap_local(vaddr);
+}
+
 static void *__iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length)
 {
 	size_t offset;
@@ -258,9 +249,21 @@ static void *__iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length)
 		return NULL;
 	}
 
-	return (void *)(uintptr_t)mr->map[m]->buf[n].addr + offset;
+	if (mr->ibmr.type == IB_MR_TYPE_USER) {
+		char *paddr;
+		struct page *pg = mr->map[m]->buf[n].page;
+
+		paddr = kmap_local_page(pg);
+		if (paddr == NULL) {
+			pr_warn("Failed to map page");
+			return NULL;
+		}
+		return paddr + offset;
+	} else
+		return (void *)(uintptr_t)mr->map[m]->buf[n].addr + offset;
 }
 
+/* must call rxe_unmap_vaddr to unmap vaddr */
 void *iova_to_vaddr(struct rxe_mr *mr, u64 iova, int length)
 {
 	if (mr->state != RXE_MR_STATE_VALID) {
@@ -326,6 +329,7 @@ int rxe_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, int length,
 		dest = (dir == RXE_TO_MR_OBJ) ? va : addr;
 
 		memcpy(dest, src, bytes);
+		rxe_unmap_vaddr(mr, va);
 
 		length	-= bytes;
 		addr	+= bytes;
diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
index 483043dc4e89..765cb9f8538a 100644
--- a/drivers/infiniband/sw/rxe/rxe_resp.c
+++ b/drivers/infiniband/sw/rxe/rxe_resp.c
@@ -636,6 +636,7 @@ static enum resp_states atomic_reply(struct rxe_qp *qp,
 
 		*vaddr = value;
 		spin_unlock_bh(&atomic_ops_lock);
+		rxe_unmap_vaddr(mr, vaddr);
 
 		qp->resp.msn++;
 
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index acab785ba7e2..6080a4b32f09 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -280,7 +280,10 @@ enum rxe_mr_lookup_type {
 #define RXE_BUF_PER_MAP		(PAGE_SIZE / sizeof(struct rxe_phys_buf))
 
 struct rxe_phys_buf {
-	u64      addr;
+	union {
+		u64 addr; /* IB_MR_TYPE_MEM_REG */
+		struct page *page; /* IB_MR_TYPE_USER */
+	};
 };
 
 struct rxe_map {
-- 
2.31.1