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

[BjÃrn TÃpel]

On Wed, 26 Jun 2019 at 17:59, Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
>
> Use kmap instead of page_address as it's not always in low memory.
>

Ah, some 32-bit love. :-) Thanks for working on this!

For future patches, please base AF_XDP patches on the bpf/bpf-next
tree instead of net/net-next.

Acked-by: BjÃrn TÃpel <bjorn.topel@xxxxxxxxx>

> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
> ---
>  net/xdp/xdp_umem.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
> index 9c6de4f114f8..d3c1411420fd 100644
> --- a/net/xdp/xdp_umem.c
> +++ b/net/xdp/xdp_umem.c
> @@ -169,6 +169,14 @@ static void xdp_umem_clear_dev(struct xdp_umem *umem)
>         }
>  }
>
> +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;
> @@ -210,6 +218,7 @@ 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);
> @@ -372,7 +381,7 @@ 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
>