From: Pavel Begunkov <asml.silence@gmail.com>
Date: Thu, 1 May 2025 12:17:17 +0000 (+0100)
Subject: io_uring/zcrx: split common area map/unmap parts
X-Git-Tag: v6.16-rc1~215^2~35
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8a62804248fff77749048a0f5511649b2569bba9;p=thirdparty%2Fkernel%2Flinux.git

io_uring/zcrx: split common area map/unmap parts

Extract area type depedent parts of io_zcrx_[un]map_area from the
generic path. It'll be helpful once there are more area memory types
and not only user pages.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/50f6e893e2d20f937e628196cbf528d15f81c289.1746097431.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 8d4cfd957e38d..34b09beba9926 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -82,22 +82,31 @@ static int io_import_area(struct io_zcrx_ifq *ifq,
 	return 0;
 }
 
-static void __io_zcrx_unmap_area(struct io_zcrx_ifq *ifq,
-				 struct io_zcrx_area *area, int nr_mapped)
+static void io_zcrx_unmap_umem(struct io_zcrx_ifq *ifq,
+				struct io_zcrx_area *area, int nr_mapped)
 {
 	int i;
 
 	for (i = 0; i < nr_mapped; i++) {
-		struct net_iov *niov = &area->nia.niovs[i];
-		dma_addr_t dma;
+		netmem_ref netmem = net_iov_to_netmem(&area->nia.niovs[i]);
+		dma_addr_t dma = page_pool_get_dma_addr_netmem(netmem);
 
-		dma = page_pool_get_dma_addr_netmem(net_iov_to_netmem(niov));
 		dma_unmap_page_attrs(ifq->dev, dma, PAGE_SIZE,
 				     DMA_FROM_DEVICE, IO_DMA_ATTR);
-		net_mp_niov_set_dma_addr(niov, 0);
 	}
 }
 
+static void __io_zcrx_unmap_area(struct io_zcrx_ifq *ifq,
+				 struct io_zcrx_area *area, int nr_mapped)
+{
+	int i;
+
+	io_zcrx_unmap_umem(ifq, area, nr_mapped);
+
+	for (i = 0; i < area->nia.num_niovs; i++)
+		net_mp_niov_set_dma_addr(&area->nia.niovs[i], 0);
+}
+
 static void io_zcrx_unmap_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 {
 	guard(mutex)(&ifq->dma_lock);
@@ -107,14 +116,10 @@ static void io_zcrx_unmap_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *are
 	area->is_mapped = false;
 }
 
-static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
+static int io_zcrx_map_area_umem(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 {
 	int i;
 
-	guard(mutex)(&ifq->dma_lock);
-	if (area->is_mapped)
-		return 0;
-
 	for (i = 0; i < area->nia.num_niovs; i++) {
 		struct net_iov *niov = &area->nia.niovs[i];
 		dma_addr_t dma;
@@ -129,9 +134,20 @@ static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 			break;
 		}
 	}
+	return i;
+}
+
+static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
+{
+	unsigned nr;
+
+	guard(mutex)(&ifq->dma_lock);
+	if (area->is_mapped)
+		return 0;
 
-	if (i != area->nia.num_niovs) {
-		__io_zcrx_unmap_area(ifq, area, i);
+	nr = io_zcrx_map_area_umem(ifq, area);
+	if (nr != area->nia.num_niovs) {
+		__io_zcrx_unmap_area(ifq, area, nr);
 		return -EINVAL;
 	}