This patch removes the TC_AT_INGRESS_OFFSET and SKB_MONO_DELIVERY_TIME_OFFSET macros. Instead, PKT_VLAN_PRESENT_OFFSET is used because all of them are at the same offset. Comment is added to make it clear that changing the position of tc_at_ingress or mono_delivery_time will require to adjust the defined macros. The earlier discussion can be found here: https://lore.kernel.org/bpf/419d994e-ff61-7c11-0ec7-11fefcb0186e@xxxxxxxxxxxxx/ Signed-off-by: Martin KaFai Lau <kafai@xxxxxx> --- include/linux/skbuff.h | 10 +++++----- net/core/filter.c | 14 +++++++------- 2 files changed, 12 insertions(+), 12 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2be263184d1e..7b0cb10e70cb 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -960,10 +960,10 @@ struct sk_buff { __u8 csum_complete_sw:1; __u8 csum_level:2; __u8 dst_pending_confirm:1; - __u8 mono_delivery_time:1; + __u8 mono_delivery_time:1; /* See SKB_MONO_DELIVERY_TIME_MASK */ #ifdef CONFIG_NET_CLS_ACT __u8 tc_skip_classify:1; - __u8 tc_at_ingress:1; + __u8 tc_at_ingress:1; /* See TC_AT_INGRESS_MASK */ #endif #ifdef CONFIG_IPV6_NDISC_NODETYPE __u8 ndisc_nodetype:2; @@ -1062,7 +1062,9 @@ struct sk_buff { #endif #define PKT_TYPE_OFFSET offsetof(struct sk_buff, __pkt_type_offset) -/* if you move pkt_vlan_present around you also must adapt these constants */ +/* if you move pkt_vlan_present, tc_at_ingress, or mono_delivery_time + * around, you also must adapt these constants. + */ #ifdef __BIG_ENDIAN_BITFIELD #define PKT_VLAN_PRESENT_BIT 7 #define TC_AT_INGRESS_MASK (1 << 0) @@ -1073,8 +1075,6 @@ struct sk_buff { #define SKB_MONO_DELIVERY_TIME_MASK (1 << 5) #endif #define PKT_VLAN_PRESENT_OFFSET offsetof(struct sk_buff, __pkt_vlan_present_offset) -#define TC_AT_INGRESS_OFFSET offsetof(struct sk_buff, __pkt_vlan_present_offset) -#define SKB_MONO_DELIVERY_TIME_OFFSET offsetof(struct sk_buff, __pkt_vlan_present_offset) #ifdef __KERNEL__ /* diff --git a/net/core/filter.c b/net/core/filter.c index 88767f7da150..738a294a3c82 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8896,7 +8896,7 @@ static struct bpf_insn *bpf_convert_dtime_type_read(const struct bpf_insn *si, __u8 tmp_reg = BPF_REG_AX; *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); + PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, SKB_MONO_DELIVERY_TIME_MASK); *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); @@ -8912,7 +8912,7 @@ static struct bpf_insn *bpf_convert_dtime_type_read(const struct bpf_insn *si, *insn++ = BPF_JMP_A(IS_ENABLED(CONFIG_NET_CLS_ACT) ? 6 : 1); #ifdef CONFIG_NET_CLS_ACT - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); /* At ingress, value_reg = 0 */ @@ -8959,14 +8959,14 @@ static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog, if (!prog->delivery_time_access) { __u8 tmp_reg = BPF_REG_AX; - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 5); /* @ingress, read __sk_buff->tstamp as the (rcv) timestamp, * so check the skb->mono_delivery_time. */ *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); + PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, SKB_MONO_DELIVERY_TIME_MASK); *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 2); @@ -8992,18 +8992,18 @@ static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog, if (!prog->delivery_time_access) { __u8 tmp_reg = BPF_REG_AX; - *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, TC_AT_INGRESS_OFFSET); + *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, TC_AT_INGRESS_MASK); *insn++ = BPF_JMP32_IMM(BPF_JEQ, tmp_reg, 0, 3); /* Writing __sk_buff->tstamp at ingress as the (rcv) timestamp. * Clear the skb->mono_delivery_time. */ *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); + PKT_VLAN_PRESENT_OFFSET); *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK); *insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, - SKB_MONO_DELIVERY_TIME_OFFSET); + PKT_VLAN_PRESENT_OFFSET); } #endif -- 2.30.2
