diff mbox series

[net-next,v13,04/10] net: page_pool: create hooks for custom memory providers

Message ID 20250204215622.695511-5-dw@davidwei.uk (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series io_uring zero copy rx | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; GEN HAS DIFF 2 files changed, 55 insertions(+);
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 4 this patch: 4
netdev/build_tools success Errors and warnings before: 26 (+1) this patch: 26 (+1)
netdev/cc_maintainers warning 2 maintainers not CCed: horms@kernel.org ilias.apalodimas@linaro.org
netdev/build_clang success Errors and warnings before: 1461 this patch: 1461
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 250 this patch: 250
netdev/checkpatch warning WARNING: Co-developed-by and Signed-off-by: name/email do not match WARNING: added, moved or deleted file(s), does MAINTAINERS need updating? WARNING: space prohibited between function name and open parenthesis '('
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 3 this patch: 3
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-02-05--09-00 (tests: 886)

Commit Message

David Wei Feb. 4, 2025, 9:56 p.m. UTC 
From: Pavel Begunkov <asml.silence@gmail.com>

A spin off from the original page pool memory providers patch by Jakub,
which allows extending page pools with custom allocators. One of such
providers is devmem TCP, and the other is io_uring zerocopy added in
following patches.

Link: https://lore.kernel.org/netdev/20230707183935.997267-7-kuba@kernel.org/
Co-developed-by: Jakub Kicinski <kuba@kernel.org> # initial mp proposal
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Wei <dw@davidwei.uk>
---
 include/net/page_pool/memory_provider.h | 15 +++++++++++++++
 include/net/page_pool/types.h           |  4 ++++
 net/core/devmem.c                       | 15 ++++++++++++++-
 net/core/page_pool.c                    | 23 +++++++++++++++--------
 4 files changed, 48 insertions(+), 9 deletions(-)
 create mode 100644 include/net/page_pool/memory_provider.h
diff mbox series

Patch

diff --git a/include/net/page_pool/memory_provider.h b/include/net/page_pool/memory_provider.h
new file mode 100644
index 000000000000..e49d0a52629d
--- /dev/null
+++ b/include/net/page_pool/memory_provider.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_PAGE_POOL_MEMORY_PROVIDER_H
+#define _NET_PAGE_POOL_MEMORY_PROVIDER_H
+
+#include <net/netmem.h>
+#include <net/page_pool/types.h>
+
+struct memory_provider_ops {
+	netmem_ref (*alloc_netmems)(struct page_pool *pool, gfp_t gfp);
+	bool (*release_netmem)(struct page_pool *pool, netmem_ref netmem);
+	int (*init)(struct page_pool *pool);
+	void (*destroy)(struct page_pool *pool);
+};
+
+#endif
diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h
index 7f405672b089..36eb57d73abc 100644
--- a/include/net/page_pool/types.h
+++ b/include/net/page_pool/types.h
@@ -152,8 +152,11 @@  struct page_pool_stats {
  */
 #define PAGE_POOL_FRAG_GROUP_ALIGN	(4 * sizeof(long))
 
+struct memory_provider_ops;
+
 struct pp_memory_provider_params {
 	void *mp_priv;
+	const struct memory_provider_ops *mp_ops;
 };
 
 struct page_pool {
@@ -216,6 +219,7 @@  struct page_pool {
 	struct ptr_ring ring;
 
 	void *mp_priv;
+	const struct memory_provider_ops *mp_ops;
 
 #ifdef CONFIG_PAGE_POOL_STATS
 	/* recycle stats are per-cpu to avoid locking */
diff --git a/net/core/devmem.c b/net/core/devmem.c
index fb0dddcb4e60..c81625ca57c6 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -16,6 +16,7 @@ 
 #include <net/netdev_queues.h>
 #include <net/netdev_rx_queue.h>
 #include <net/page_pool/helpers.h>
+#include <net/page_pool/memory_provider.h>
 #include <trace/events/page_pool.h>
 
 #include "devmem.h"
@@ -27,6 +28,8 @@ 
 /* Protected by rtnl_lock() */
 static DEFINE_XARRAY_FLAGS(net_devmem_dmabuf_bindings, XA_FLAGS_ALLOC1);
 
+static const struct memory_provider_ops dmabuf_devmem_ops;
+
 static void net_devmem_dmabuf_free_chunk_owner(struct gen_pool *genpool,
 					       struct gen_pool_chunk *chunk,
 					       void *not_used)
@@ -118,6 +121,7 @@  void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding)
 		WARN_ON(rxq->mp_params.mp_priv != binding);
 
 		rxq->mp_params.mp_priv = NULL;
+		rxq->mp_params.mp_ops = NULL;
 
 		rxq_idx = get_netdev_rx_queue_index(rxq);
 
@@ -153,7 +157,7 @@  int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 	}
 
 	rxq = __netif_get_rx_queue(dev, rxq_idx);
-	if (rxq->mp_params.mp_priv) {
+	if (rxq->mp_params.mp_ops) {
 		NL_SET_ERR_MSG(extack, "designated queue already memory provider bound");
 		return -EEXIST;
 	}
@@ -171,6 +175,7 @@  int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 		return err;
 
 	rxq->mp_params.mp_priv = binding;
+	rxq->mp_params.mp_ops = &dmabuf_devmem_ops;
 
 	err = netdev_rx_queue_restart(dev, rxq_idx);
 	if (err)
@@ -180,6 +185,7 @@  int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 
 err_xa_erase:
 	rxq->mp_params.mp_priv = NULL;
+	rxq->mp_params.mp_ops = NULL;
 	xa_erase(&binding->bound_rxqs, xa_idx);
 
 	return err;
@@ -399,3 +405,10 @@  bool mp_dmabuf_devmem_release_page(struct page_pool *pool, netmem_ref netmem)
 	/* We don't want the page pool put_page()ing our net_iovs. */
 	return false;
 }
+
+static const struct memory_provider_ops dmabuf_devmem_ops = {
+	.init			= mp_dmabuf_devmem_init,
+	.destroy		= mp_dmabuf_devmem_destroy,
+	.alloc_netmems		= mp_dmabuf_devmem_alloc_netmems,
+	.release_netmem		= mp_dmabuf_devmem_release_page,
+};
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index f5e908c9e7ad..d632cf2c91c3 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -13,6 +13,7 @@ 
 
 #include <net/netdev_rx_queue.h>
 #include <net/page_pool/helpers.h>
+#include <net/page_pool/memory_provider.h>
 #include <net/xdp.h>
 
 #include <linux/dma-direction.h>
@@ -285,13 +286,19 @@  static int page_pool_init(struct page_pool *pool,
 		rxq = __netif_get_rx_queue(pool->slow.netdev,
 					   pool->slow.queue_idx);
 		pool->mp_priv = rxq->mp_params.mp_priv;
+		pool->mp_ops = rxq->mp_params.mp_ops;
 	}
 
-	if (pool->mp_priv) {
+	if (pool->mp_ops) {
 		if (!pool->dma_map || !pool->dma_sync)
 			return -EOPNOTSUPP;
 
-		err = mp_dmabuf_devmem_init(pool);
+		if (WARN_ON(!is_kernel_rodata((unsigned long)pool->mp_ops))) {
+			err = -EFAULT;
+			goto free_ptr_ring;
+		}
+
+		err = pool->mp_ops->init(pool);
 		if (err) {
 			pr_warn("%s() mem-provider init failed %d\n", __func__,
 				err);
@@ -587,8 +594,8 @@  netmem_ref page_pool_alloc_netmems(struct page_pool *pool, gfp_t gfp)
 		return netmem;
 
 	/* Slow-path: cache empty, do real allocation */
-	if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_priv)
-		netmem = mp_dmabuf_devmem_alloc_netmems(pool, gfp);
+	if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops)
+		netmem = pool->mp_ops->alloc_netmems(pool, gfp);
 	else
 		netmem = __page_pool_alloc_pages_slow(pool, gfp);
 	return netmem;
@@ -679,8 +686,8 @@  void page_pool_return_page(struct page_pool *pool, netmem_ref netmem)
 	bool put;
 
 	put = true;
-	if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_priv)
-		put = mp_dmabuf_devmem_release_page(pool, netmem);
+	if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops)
+		put = pool->mp_ops->release_netmem(pool, netmem);
 	else
 		__page_pool_release_page_dma(pool, netmem);
 
@@ -1048,8 +1055,8 @@  static void __page_pool_destroy(struct page_pool *pool)
 	page_pool_unlist(pool);
 	page_pool_uninit(pool);
 
-	if (pool->mp_priv) {
-		mp_dmabuf_devmem_destroy(pool);
+	if (pool->mp_ops) {
+		pool->mp_ops->destroy(pool);
 		static_branch_dec(&page_pool_mem_providers);
 	}