[PATCH net-next 23/27] net/bpf: split VLAN_PRESENT bit handling from VLAN_TCI
From: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Date: 2016-12-13 00:18:56
Also in:
lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> --- net/core/filter.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-)
diff --git a/net/core/filter.c b/net/core/filter.c
index b146170..c3321f1 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -188,22 +188,20 @@ static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg, break; case SKF_AD_VLAN_TAG: - case SKF_AD_VLAN_TAG_PRESENT: BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2); - BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */ *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, offsetof(struct sk_buff, vlan_tci)); - if (skb_field == SKF_AD_VLAN_TAG) { - *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, - ~VLAN_TAG_PRESENT); - } else { - /* dst_reg >>= 12 */ - *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12); - /* dst_reg &= 1 */ - *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); - } +#ifdef VLAN_TAG_PRESENT + *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, ~VLAN_TAG_PRESENT); +#endif + break; + case SKF_AD_VLAN_TAG_PRESENT: + *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET()); + if (PKT_VLAN_PRESENT_BIT) + *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT); + *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); break; }
--
2.10.2