diff options
| -rw-r--r-- | include/uapi/linux/bpf.h | 9 | ||||
| -rw-r--r-- | net/core/filter.c | 19 |
2 files changed, 28 insertions, 0 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index f44504d875e2..c14ca1cd6297 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -348,6 +348,15 @@ enum bpf_func_id { * < 0 error */ BPF_FUNC_skb_in_cgroup, + + /** + * bpf_get_hash_recalc(skb) + * Retrieve and possibly recalculate skb->hash. + * @skb: pointer to skb + * Return: hash + */ + BPF_FUNC_get_hash_recalc, + __BPF_FUNC_MAX_ID, }; diff --git a/net/core/filter.c b/net/core/filter.c index 54071cf70fb5..10c4a2f9e8bb 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1729,6 +1729,23 @@ static const struct bpf_func_proto bpf_get_route_realm_proto = { .arg1_type = ARG_PTR_TO_CTX, }; +static u64 bpf_get_hash_recalc(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + /* If skb_clear_hash() was called due to mangling, we can + * trigger SW recalculation here. Later access to hash + * can then use the inline skb->hash via context directly + * instead of calling this helper again. + */ + return skb_get_hash((struct sk_buff *) (unsigned long) r1); +} + +static const struct bpf_func_proto bpf_get_hash_recalc_proto = { + .func = bpf_get_hash_recalc, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + static u64 bpf_skb_vlan_push(u64 r1, u64 r2, u64 vlan_tci, u64 r4, u64 r5) { struct sk_buff *skb = (struct sk_buff *) (long) r1; @@ -2337,6 +2354,8 @@ tc_cls_act_func_proto(enum bpf_func_id func_id) return &bpf_redirect_proto; case BPF_FUNC_get_route_realm: return &bpf_get_route_realm_proto; + case BPF_FUNC_get_hash_recalc: + return &bpf_get_hash_recalc_proto; case BPF_FUNC_perf_event_output: return bpf_get_event_output_proto(); case BPF_FUNC_get_smp_processor_id: |