nfp: bpf: add basic support for adjust head call
Support bpf_xdp_adjust_head(). We need to check whether the
packet offset after adjustment is within datapath's limits.
We also check if the frame is at least ETH_HLEN long (similar
to the kernel implementation).
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c b/drivers/net/ethernet/netronome/nfp/bpf/main.c
index f76bb40..bd4a1dc 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c
@@ -39,6 +39,7 @@
#include "../nfp_main.h"
#include "../nfp_net.h"
#include "../nfp_port.h"
+#include "fw.h"
#include "main.h"
static bool nfp_net_ebpf_capable(struct nfp_net *nn)
@@ -156,6 +157,36 @@ static bool nfp_bpf_tc_busy(struct nfp_app *app, struct nfp_net *nn)
return nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF;
}
+static int
+nfp_bpf_parse_cap_adjust_head(struct nfp_app_bpf *bpf, void __iomem *value,
+ u32 length)
+{
+ struct nfp_bpf_cap_tlv_adjust_head __iomem *cap = value;
+ struct nfp_cpp *cpp = bpf->app->pf->cpp;
+
+ if (length < sizeof(*cap)) {
+ nfp_err(cpp, "truncated adjust_head TLV: %d\n", length);
+ return -EINVAL;
+ }
+
+ bpf->adjust_head.flags = readl(&cap->flags);
+ bpf->adjust_head.off_min = readl(&cap->off_min);
+ bpf->adjust_head.off_max = readl(&cap->off_max);
+
+ if (bpf->adjust_head.off_min > bpf->adjust_head.off_max) {
+ nfp_err(cpp, "invalid adjust_head TLV: min > max\n");
+ return -EINVAL;
+ }
+ if (!FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_min) ||
+ !FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_max)) {
+ nfp_warn(cpp, "disabling adjust_head - driver expects min/max to fit in as immediates\n");
+ memset(&bpf->adjust_head, 0, sizeof(bpf->adjust_head));
+ return 0;
+ }
+
+ return 0;
+}
+
static int nfp_bpf_parse_capabilities(struct nfp_app *app)
{
struct nfp_cpp *cpp = app->pf->cpp;
@@ -169,16 +200,23 @@ static int nfp_bpf_parse_capabilities(struct nfp_app *app)
start = mem;
while (mem - start + 8 < nfp_cpp_area_size(area)) {
+ u8 __iomem *value;
u32 type, length;
type = readl(mem);
length = readl(mem + 4);
+ value = mem + 8;
mem += 8 + length;
if (mem - start > nfp_cpp_area_size(area))
goto err_release_free;
switch (type) {
+ case NFP_BPF_CAP_TYPE_ADJUST_HEAD:
+ if (nfp_bpf_parse_cap_adjust_head(app->priv, value,
+ length))
+ goto err_release_free;
+ break;
default:
nfp_dbg(cpp, "unknown BPF capability: %d\n", type);
break;