netdev - [RFC 05/12] net: page_pool: factor out releasing DMA from releasing the page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Fri,  7 Jul 2023 11:39:28 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: netdev@...r.kernel.org
Cc: almasrymina@...gle.com,
	hawk@...nel.org,
	ilias.apalodimas@...aro.org,
	edumazet@...gle.com,
	dsahern@...il.com,
	michael.chan@...adcom.com,
	willemb@...gle.com,
	Jakub Kicinski <kuba@...nel.org>
Subject: [RFC 05/12] net: page_pool: factor out releasing DMA from releasing the page

Releasing the DMA mapping will be useful for other types
of pages, so factor it out. Make sure compiler inlines it,
to avoid any regressions.

Signed-off-by: Jakub Kicinski <kuba@...nel.org>
---
 net/core/page_pool.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 7ca456bfab71..09f8c34ad4a7 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -487,21 +487,16 @@ static s32 page_pool_inflight(struct page_pool *pool)
 	return inflight;
 }
 
-/* Disconnects a page (from a page_pool).  API users can have a need
- * to disconnect a page (from a page_pool), to allow it to be used as
- * a regular page (that will eventually be returned to the normal
- * page-allocator via put_page).
- */
-static void page_pool_return_page(struct page_pool *pool, struct page *page)
+static __always_inline
+void __page_pool_release_page_dma(struct page_pool *pool, struct page *page)
 {
 	dma_addr_t dma;
-	int count;
 
 	if (!(pool->p.flags & PP_FLAG_DMA_MAP))
 		/* Always account for inflight pages, even if we didn't
 		 * map them
 		 */
-		goto skip_dma_unmap;
+		return;
 
 	dma = page_pool_get_dma_addr(page);
 
@@ -510,7 +505,19 @@ static void page_pool_return_page(struct page_pool *pool, struct page *page)
 			     PAGE_SIZE << pool->p.order, pool->p.dma_dir,
 			     DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING);
 	page_pool_set_dma_addr(page, 0);
-skip_dma_unmap:
+}
+
+/* Disconnects a page (from a page_pool).  API users can have a need
+ * to disconnect a page (from a page_pool), to allow it to be used as
+ * a regular page (that will eventually be returned to the normal
+ * page-allocator via put_page).
+ */
+void page_pool_return_page(struct page_pool *pool, struct page *page)
+{
+	int count;
+
+	__page_pool_release_page_dma(pool, page);
+
 	page_pool_clear_pp_info(page);
 
 	/* This may be the last page returned, releasing the pool, so
-- 
2.41.0