[RFC v2 10/21] RDMA/umem: Preallocate and cache IOVA for UMEM ODP

[Leon Romanovsky <leon@kernel.org>]

From: Leon Romanovsky <leonro@nvidia.com>

As a preparation to provide two step interface to map pages,
preallocate IOVA when UMEM is initialized.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/infiniband/core/umem_odp.c | 13 ++++++++++++-
 include/rdma/ib_umem_odp.h         |  1 +
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index e9fa22d31c23..01cbf7f55b3a 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -50,6 +50,7 @@
 static inline int ib_init_umem_odp(struct ib_umem_odp *umem_odp,
 				   const struct mmu_interval_notifier_ops *ops)
 {
+	struct ib_device *dev = umem_odp->umem.ibdev;
 	int ret;
 
 	umem_odp->umem.is_odp = 1;
@@ -87,15 +88,24 @@ static inline int ib_init_umem_odp(struct ib_umem_odp *umem_odp,
 			goto out_pfn_list;
 		}
 
+		dma_init_iova_state(&umem_odp->state, dev->dma_device,
+				    DMA_BIDIRECTIONAL);
+		ret = dma_alloc_iova(&umem_odp->state, end - start);
+		if (ret)
+			goto out_dma_list;
+
+
 		ret = mmu_interval_notifier_insert(&umem_odp->notifier,
 						   umem_odp->umem.owning_mm,
 						   start, end - start, ops);
 		if (ret)
-			goto out_dma_list;
+			goto out_free_iova;
 	}
 
 	return 0;
 
+out_free_iova:
+	dma_free_iova(&umem_odp->state);
 out_dma_list:
 	kvfree(umem_odp->dma_list);
 out_pfn_list:
@@ -274,6 +284,7 @@ void ib_umem_odp_release(struct ib_umem_odp *umem_odp)
 					    ib_umem_end(umem_odp));
 		mutex_unlock(&umem_odp->umem_mutex);
 		mmu_interval_notifier_remove(&umem_odp->notifier);
+		dma_free_iova(&umem_odp->state);
 		kvfree(umem_odp->dma_list);
 		kvfree(umem_odp->pfn_list);
 	}
diff --git a/include/rdma/ib_umem_odp.h b/include/rdma/ib_umem_odp.h
index 0844c1d05ac6..c0c1215925eb 100644
--- a/include/rdma/ib_umem_odp.h
+++ b/include/rdma/ib_umem_odp.h
@@ -23,6 +23,7 @@ struct ib_umem_odp {
 	 * See ODP_READ_ALLOWED_BIT and ODP_WRITE_ALLOWED_BIT.
 	 */
 	dma_addr_t		*dma_list;
+	struct dma_iova_state state;
 	/*
 	 * The umem_mutex protects the page_list and dma_list fields of an ODP
 	 * umem, allowing only a single thread to map/unmap pages. The mutex
-- 
2.46.0