2019-08-08 09:39:20

by Ivan Khoronzhuk

Subject: [PATCH v2 bpf-next] xdp: xdp_umem: fix umem pages mapping for 32bits systems

Use kmap instead of page_address as it's not always in low memory.

Acked-by: Björn Töpel <[email protected]>
Signed-off-by: Ivan Khoronzhuk <[email protected]>
---

Based on bpf-next/master
v2..v1:
included highmem.h

v1: https://lkml.org/lkml/2019/6/26/693

net/xdp/xdp_umem.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index 83de74ca729a..a0607969f8c0 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -14,6 +14,7 @@
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/idr.h>
+#include <linux/highmem.h>

#include "xdp_umem.h"
#include "xsk_queue.h"
@@ -164,6 +165,14 @@ void xdp_umem_clear_dev(struct xdp_umem *umem)
umem->zc = false;
}

+static void xdp_umem_unmap_pages(struct xdp_umem *umem)
+{
+ unsigned int i;
+
+ for (i = 0; i < umem->npgs; i++)
+ kunmap(umem->pgs[i]);
+}
+
static void xdp_umem_unpin_pages(struct xdp_umem *umem)
{
unsigned int i;
@@ -207,6 +216,7 @@ static void xdp_umem_release(struct xdp_umem *umem)

xsk_reuseq_destroy(umem);

+ xdp_umem_unmap_pages(umem);
xdp_umem_unpin_pages(umem);

kfree(umem->pages);
@@ -369,7 +379,7 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr)
}

for (i = 0; i < umem->npgs; i++)
- umem->pages[i].addr = page_address(umem->pgs[i]);
+ umem->pages[i].addr = kmap(umem->pgs[i]);

return 0;

--
2.17.1

2019-08-09 16:14:02

by Daniel Borkmann

Subject: Re: [PATCH v2 bpf-next] xdp: xdp_umem: fix umem pages mapping for 32bits systems

On 8/8/19 11:38 AM, Ivan Khoronzhuk wrote:
> Use kmap instead of page_address as it's not always in low memory.
>
> Acked-by: Björn Töpel <[email protected]>
> Signed-off-by: Ivan Khoronzhuk <[email protected]>

Applied, thanks!