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

From: Leon Romanovsky
Date: Thu Sep 12 2024 - 07:20:23 EST


From: Leon Romanovsky <leonro@xxxxxxxxxx>

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

Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
---
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