On 25/07/2019 11:15, Maxim Mikityanskiy wrote:
On 2019-07-24 08:10, 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>
---
v3:
- Use new helper function to handle offset
---
drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 8 ++++++--
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c | 9 +++++++--
2 files changed, 13 insertions(+), 4 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);
+ }
What's missed is that umem_headroom is added to handle directly in
mlx5e_xsk_page_alloc_umem. In my understanding umem_headroom should go
to the offset part (high 16 bits) of the handle, to
xsk_umem_handle_offset has to support increasing the offset.
Will look into it and make the changes for the v4
switch (act) {
case XDP_PASS:
*rx_headroom = xdp.data - xdp.data_hard_start;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
index 35e188cf4ea4..f596e63cba00 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
@@ -61,6 +61,7 @@ bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget)
struct mlx5e_xdp_xmit_data xdptxd;
bool work_done = true;
bool flush = false;
+ u64 addr, offset;
xdpi.mode = MLX5E_XDP_XMIT_MODE_XSK;
@@ -82,8 +83,12 @@ bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget)
break;
}
- xdptxd.dma_addr = xdp_umem_get_dma(umem, desc.addr);
- xdptxd.data = xdp_umem_get_data(umem, desc.addr);
+ /* for unaligned chunks need to take offset from upper bits */
+ offset = (desc.addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT);
+ addr = (desc.addr & XSK_UNALIGNED_BUF_ADDR_MASK);
+
+ xdptxd.dma_addr = xdp_umem_get_dma(umem, addr + offset);
+ xdptxd.data = xdp_umem_get_data(umem, addr + offset);
Why can't these calculations be encapsulated into
xdp_umem_get_{dma,data}? I think they are common for all drivers, aren't
they?
Even if there is some reason not to put this bitshifting stuff into
xdp_umem_get_* functions, I suggest to encapsulate it into a function
anyway, because it's a good idea to keep those calculations in a single
place.
Nice suggestion! I will move it to the xdp_umem_get_* functions in the
v4. Thanks
