netdev - [PATCH io_uring for-6.18 11/20] io_uring/zcrx: set sgt for umem area

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]

Message-ID: <f07b13cee1fcf13eb3e0c739f8efb223de370432.1758030357.git.asml.silence@gmail.com>
Date: Tue, 16 Sep 2025 15:27:54 +0100
From: Pavel Begunkov <asml.silence@...il.com>
To: io-uring@...r.kernel.org
Cc: asml.silence@...il.com,
	axboe@...nel.dk,
	netdev@...r.kernel.org
Subject: [PATCH io_uring for-6.18 11/20] io_uring/zcrx: set sgt for umem area

Set struct io_zcrx_mem::sgt for umem areas as well to simplify looking
up the current sg table.

Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 io_uring/zcrx.c | 14 ++++++--------
 io_uring/zcrx.h |  2 +-
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index bcefb302aadf..764723bf04d6 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -52,9 +52,9 @@ static inline struct page *io_zcrx_iov_page(const struct net_iov *niov)
 }
 
 static int io_populate_area_dma(struct io_zcrx_ifq *ifq,
-				struct io_zcrx_area *area,
-				struct sg_table *sgt)
+				struct io_zcrx_area *area)
 {
+	struct sg_table *sgt = area->mem.sgt;
 	struct scatterlist *sg;
 	unsigned i, niov_idx = 0;
 
@@ -197,6 +197,7 @@ static int io_import_umem(struct io_zcrx_ifq *ifq,
 	if (ret < 0)
 		mem->account_pages = 0;
 
+	mem->sgt = &mem->page_sg_table;
 	mem->pages = pages;
 	mem->nr_folios = nr_pages;
 	mem->size = area_reg->len;
@@ -211,7 +212,8 @@ static void io_release_area_mem(struct io_zcrx_mem *mem)
 	}
 	if (mem->pages) {
 		unpin_user_pages(mem->pages, mem->nr_folios);
-		sg_free_table(&mem->page_sg_table);
+		sg_free_table(mem->sgt);
+		mem->sgt = NULL;
 		kvfree(mem->pages);
 	}
 }
@@ -263,7 +265,6 @@ static void io_zcrx_unmap_area(struct io_zcrx_ifq *ifq,
 
 static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 {
-	struct sg_table *sgt;
 	int ret;
 
 	guard(mutex)(&ifq->dma_lock);
@@ -275,12 +276,9 @@ static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 				      DMA_FROM_DEVICE, IO_DMA_ATTR);
 		if (ret < 0)
 			return ret;
-		sgt = &area->mem.page_sg_table;
-	} else {
-		sgt = area->mem.sgt;
 	}
 
-	ret = io_populate_area_dma(ifq, area, sgt);
+	ret = io_populate_area_dma(ifq, area);
 	if (ret == 0)
 		area->is_mapped = true;
 	return ret;
diff --git a/io_uring/zcrx.h b/io_uring/zcrx.h
index 24ed473632c6..27d7cf28a04e 100644
--- a/io_uring/zcrx.h
+++ b/io_uring/zcrx.h
@@ -16,10 +16,10 @@ struct io_zcrx_mem {
 	unsigned long			nr_folios;
 	struct sg_table			page_sg_table;
 	unsigned long			account_pages;
+	struct sg_table			*sgt;
 
 	struct dma_buf_attachment	*attach;
 	struct dma_buf			*dmabuf;
-	struct sg_table			*sgt;
 };
 
 struct io_zcrx_area {
-- 
2.49.0