[RFC PATCH v3 19/20] net: page pool: generalise ppiov dma address get

[David Wei <dw@davidwei.uk>]

From: Pavel Begunkov <asml.silence@gmail.com>

io_uring pp memory provider doesn't have contiguous dma addresses,
implement page_pool_iov_dma_addr() via callbacks.

Note: it might be better to stash dma address into struct page_pool_iov.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Wei <dw@davidwei.uk>
---
 include/net/page_pool/helpers.h | 5 +----
 include/net/page_pool/types.h   | 2 ++
 io_uring/zc_rx.c                | 8 ++++++++
 net/core/page_pool.c            | 9 +++++++++
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h
index aca3a52d0e22..10dba1f2aa0c 100644
--- a/include/net/page_pool/helpers.h
+++ b/include/net/page_pool/helpers.h
@@ -105,10 +105,7 @@ static inline unsigned int page_pool_iov_idx(const struct page_pool_iov *ppiov)
 static inline dma_addr_t
 page_pool_iov_dma_addr(const struct page_pool_iov *ppiov)
 {
-	struct dmabuf_genpool_chunk_owner *owner = page_pool_iov_owner(ppiov);
-
-	return owner->base_dma_addr +
-	       ((dma_addr_t)page_pool_iov_idx(ppiov) << PAGE_SHIFT);
+	return ppiov->pp->mp_ops->ppiov_dma_addr(ppiov);
 }
 
 static inline unsigned long
diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h
index f54ee759e362..1b9266835ab6 100644
--- a/include/net/page_pool/types.h
+++ b/include/net/page_pool/types.h
@@ -125,6 +125,7 @@ struct page_pool_stats {
 #endif
 
 struct mem_provider;
+struct page_pool_iov;
 
 enum pp_memory_provider_type {
 	__PP_MP_NONE, /* Use system allocator directly */
@@ -138,6 +139,7 @@ struct pp_memory_provider_ops {
 	void (*scrub)(struct page_pool *pool);
 	struct page *(*alloc_pages)(struct page_pool *pool, gfp_t gfp);
 	bool (*release_page)(struct page_pool *pool, struct page *page);
+	dma_addr_t (*ppiov_dma_addr)(const struct page_pool_iov *ppiov);
 };
 
 extern const struct pp_memory_provider_ops dmabuf_devmem_ops;
diff --git a/io_uring/zc_rx.c b/io_uring/zc_rx.c
index f7d99d569885..20fb89e6bad7 100644
--- a/io_uring/zc_rx.c
+++ b/io_uring/zc_rx.c
@@ -600,12 +600,20 @@ static void io_pp_zc_destroy(struct page_pool *pp)
 	percpu_ref_put(&ifq->ctx->refs);
 }
 
+static dma_addr_t io_pp_zc_ppiov_dma_addr(const struct page_pool_iov *ppiov)
+{
+	struct io_zc_rx_buf *buf = io_iov_to_buf((struct page_pool_iov *)ppiov);
+
+	return buf->dma;
+}
+
 const struct pp_memory_provider_ops io_uring_pp_zc_ops = {
 	.alloc_pages		= io_pp_zc_alloc_pages,
 	.release_page		= io_pp_zc_release_page,
 	.init			= io_pp_zc_init,
 	.destroy		= io_pp_zc_destroy,
 	.scrub			= io_pp_zc_scrub,
+	.ppiov_dma_addr		= io_pp_zc_ppiov_dma_addr,
 };
 EXPORT_SYMBOL(io_uring_pp_zc_ops);
 
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index ebf5ff009d9d..6586631ecc2e 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -1105,10 +1105,19 @@ static bool mp_dmabuf_devmem_release_page(struct page_pool *pool,
 	return true;
 }
 
+static dma_addr_t mp_dmabuf_devmem_ppiov_dma_addr(const struct page_pool_iov *ppiov)
+{
+	struct dmabuf_genpool_chunk_owner *owner = page_pool_iov_owner(ppiov);
+
+	return owner->base_dma_addr +
+	       ((dma_addr_t)page_pool_iov_idx(ppiov) << PAGE_SHIFT);
+}
+
 const struct pp_memory_provider_ops dmabuf_devmem_ops = {
 	.init			= mp_dmabuf_devmem_init,
 	.destroy		= mp_dmabuf_devmem_destroy,
 	.alloc_pages		= mp_dmabuf_devmem_alloc_pages,
 	.release_page		= mp_dmabuf_devmem_release_page,
+	.ppiov_dma_addr		= mp_dmabuf_devmem_ppiov_dma_addr,
 };
 EXPORT_SYMBOL(dmabuf_devmem_ops);
-- 
2.39.3