[PATCH 2/2] bpf: report queue_index to xdp_rxq_info in cpumap and devmap

[Anand Kumar Shaw]

When a second-stage XDP program runs on a cpumap or devmap redirected
frame, ctx->rx_queue_index always returns 0 because the reconstructed
xdp_rxq_info never had queue_index set.

Now that xdp_frame carries queue_index, set rxq.queue_index from
xdpf->queue_index in both cpu_map_bpf_prog_run_xdp() and
dev_map_bpf_prog_run(). This allows BPF programs to correctly identify
the original hardware RX queue after a cpumap or devmap redirect.

Resolves a TODO left since the cpumap implementation.

Signed-off-by: Anand Kumar Shaw <anandkrshawheritage@xxxxxxxxx>
---
 kernel/bpf/cpumap.c | 2 +-
 kernel/bpf/devmap.c | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index 04171fbc39cb..f5b2ff17e328 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -195,7 +195,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu,
 
 		rxq.dev = xdpf->dev_rx;
 		rxq.mem.type = xdpf->mem_type;
-		/* TODO: report queue_index to xdp_rxq_info */
+		rxq.queue_index = xdpf->queue_index;
 
 		xdp_convert_frame_to_buff(xdpf, &xdp);
 
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 2625601de76e..aa2e929792c8 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -346,6 +346,7 @@ static int dev_map_bpf_prog_run(struct bpf_prog *xdp_prog,
 		u32 act;
 		int err;
 
+		rxq.queue_index = xdpf->queue_index;
 		xdp_convert_frame_to_buff(xdpf, &xdp);
 		xdp.txq = &txq;
 		xdp.rxq = &rxq;
-- 
2.39.5 (Apple Git-154)