On 2019-07-30 11:53, Kevin Laatz wrote:
> With the addition of the unaligned chunks option, we need to make sure we
> handle the offsets accordingly based on the mode we are currently running
> in. This patch modifies the driver to appropriately mask the address for
> each case.
>
> Signed-off-by: Kevin Laatz <kevin.laatz@xxxxxxxxx>
Please note that this patch doesn't actually add the support for the new
feature, because the validation checks in mlx5e_rx_get_linear_frag_sz
and mlx5e_validate_xsk_param need to be relaxed. Currently the frame
size of PAGE_SIZE is forced, and the fragment size is increased to
PAGE_SIZE in case of XDP (including XSK).
After making the changes required to permit frame sizes smaller than
PAGE_SIZE, our Striding RQ feature will be used in a way we haven't used
it before, so we need to verify with the hardware team that this usage
is legitimate.
> ---
> v3:
> - Use new helper function to handle offset
>
> v4:
> - fixed headroom addition to handle. Using xsk_umem_adjust_headroom()
> now.
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 8 ++++++--
> drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c | 3 ++-
> 2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> index b0b982cf69bb..d5245893d2c8 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> @@ -122,6 +122,7 @@ bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct mlx5e_dma_info *di,
> void *va, u16 *rx_headroom, u32 *len, bool xsk)
> {
> struct bpf_prog *prog = READ_ONCE(rq->xdp_prog);
> + struct xdp_umem *umem = rq->umem;
> struct xdp_buff xdp;
> u32 act;
> int err;
> @@ -138,8 +139,11 @@ bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct mlx5e_dma_info *di,
> xdp.rxq = &rq->xdp_rxq;
>
> act = bpf_prog_run_xdp(prog, &xdp);
> - if (xsk)
> - xdp.handle += xdp.data - xdp.data_hard_start;
> + if (xsk) {
> + u64 off = xdp.data - xdp.data_hard_start;
> +
> + xdp.handle = xsk_umem_handle_offset(umem, xdp.handle, off);
> + }
> switch (act) {
> case XDP_PASS:
> *rx_headroom = xdp.data - xdp.data_hard_start;
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> index 6a55573ec8f2..7c49a66d28c9 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> @@ -24,7 +24,8 @@ int mlx5e_xsk_page_alloc_umem(struct mlx5e_rq *rq,
> if (!xsk_umem_peek_addr_rq(umem, &handle))
> return -ENOMEM;
>
> - dma_info->xsk.handle = handle + rq->buff.umem_headroom;
> + dma_info->xsk.handle = xsk_umem_adjust_offset(umem, handle,
> + rq->buff.umem_headroom);
> dma_info->xsk.data = xdp_umem_get_data(umem, dma_info->xsk.handle);
>
> /* No need to add headroom to the DMA address. In striding RQ case, we
>
