[PATCH bpf-next v3 06/11] mlx5e: modify driver for handling offsets

[Kevin Laatz <kevin.laatz@xxxxxxxxx>]

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);
+	}
 	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);
 		xdptxd.len = desc.len;
 
 		dma_sync_single_for_device(sq->pdev, xdptxd.dma_addr,
-- 
2.17.1