net: remove VLAN_TAG_PRESENT

Replace VLAN_TAG_PRESENT with single bit flag and free up
VLAN.CFI overload. Now VLAN.CFI is visible in networking stack
and can be passed around intact.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c
index de4c637..3a0e34f 100644 (file)
--- a/arch/mips/net/bpf_jit.c
+++ b/arch/mips/net/bpf_jit.c
@@ -1164,9 +1164,6 @@ jmp_cmp:
                                                  vlan_tci) != 2);
                        off = offsetof(struct sk_buff, vlan_tci);
                        emit_half_load_unsigned(r_A, r_skb, off, ctx);
-#ifdef VLAN_TAG_PRESENT
-                       emit_andi(r_A, r_A, (u16)~VLAN_TAG_PRESENT, ctx);
-#endif
                        break;
                case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
                        ctx->flags |= SEEN_SKB | SEEN_A;

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index dc4a2f5..91d223c 100644 (file)
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -383,9 +383,6 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 
                        PPC_LHZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
                                                          vlan_tci));
-#ifdef VLAN_TAG_PRESENT
-                       PPC_ANDI(r_A, r_A, ~VLAN_TAG_PRESENT);
-#endif
                        break;
                case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
                        PPC_LBZ_OFFS(r_A, r_skb, PKT_VLAN_PRESENT_OFFSET());

diff --git a/arch/sparc/net/bpf_jit_comp_32.c b/arch/sparc/net/bpf_jit_comp_32.c
index 48f3c04..84cc8f7 100644 (file)
--- a/arch/sparc/net/bpf_jit_comp_32.c
+++ b/arch/sparc/net/bpf_jit_comp_32.c
@@ -553,10 +553,6 @@ void bpf_jit_compile(struct bpf_prog *fp)
                                break;
                        case BPF_ANC | SKF_AD_VLAN_TAG:
                                emit_skb_load16(vlan_tci, r_A);
-#ifdef VLAN_TAG_PRESENT
-                               emit_loadimm(~VLAN_TAG_PRESENT, r_TMP);
-                               emit_and(r_A, r_TMP, r_A);
-#endif
                                break;
                        case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
                                __emit_skb_load8(__pkt_vlan_present_offset, r_A);

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 1be5230..7a541ea 100644 (file)
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -66,7 +66,6 @@ static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
 #define VLAN_PRIO_MASK         0xe000 /* Priority Code Point */
 #define VLAN_PRIO_SHIFT                13
 #define VLAN_CFI_MASK          0x1000 /* Canonical Format Indicator */
-#define VLAN_TAG_PRESENT       VLAN_CFI_MASK
 #define VLAN_VID_MASK          0x0fff /* VLAN Identifier */
 #define VLAN_N_VID             4096
 
@@ -78,8 +77,8 @@ static inline bool is_vlan_dev(const struct net_device *dev)
         return dev->priv_flags & IFF_802_1Q_VLAN;
 }
 
-#define skb_vlan_tag_present(__skb)    ((__skb)->vlan_tci & VLAN_TAG_PRESENT)
-#define skb_vlan_tag_get(__skb)                ((__skb)->vlan_tci & ~VLAN_TAG_PRESENT)
+#define skb_vlan_tag_present(__skb)    ((__skb)->vlan_present)
+#define skb_vlan_tag_get(__skb)                ((__skb)->vlan_tci)
 #define skb_vlan_tag_get_id(__skb)     ((__skb)->vlan_tci & VLAN_VID_MASK)
 #define skb_vlan_tag_get_prio(__skb)   (((__skb)->vlan_tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT)
 
@@ -480,7 +479,7 @@ static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
  */
 static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb)
 {
-       skb->vlan_tci = 0;
+       skb->vlan_present = 0;
 }
 
 /**
@@ -492,6 +491,7 @@ static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb)
  */
 static inline void __vlan_hwaccel_copy_tag(struct sk_buff *dst, const struct sk_buff *src)
 {
+       dst->vlan_present = src->vlan_present;
        dst->vlan_proto = src->vlan_proto;
        dst->vlan_tci = src->vlan_tci;
 }
@@ -526,7 +526,8 @@ static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
                                          __be16 vlan_proto, u16 vlan_tci)
 {
        skb->vlan_proto = vlan_proto;
-       skb->vlan_tci = VLAN_TAG_PRESENT | vlan_tci;
+       skb->vlan_tci = vlan_tci;
+       skb->vlan_present = 1;
 }
 
 /**

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 99f3877..b9aa0d1 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -777,6 +777,14 @@ struct sk_buff {
        __u8                    encap_hdr_csum:1;
        __u8                    csum_valid:1;
 
+#ifdef __BIG_ENDIAN_BITFIELD
+#define PKT_VLAN_PRESENT_BIT   7
+#else
+#define PKT_VLAN_PRESENT_BIT   0
+#endif
+#define PKT_VLAN_PRESENT_OFFSET()      offsetof(struct sk_buff, __pkt_vlan_present_offset)
+       __u8                    __pkt_vlan_present_offset[0];
+       __u8                    vlan_present:1;
        __u8                    csum_complete_sw:1;
        __u8                    csum_level:2;
        __u8                    csum_not_inet:1;
@@ -784,8 +792,8 @@ struct sk_buff {
 #ifdef CONFIG_IPV6_NDISC_NODETYPE
        __u8                    ndisc_nodetype:2;
 #endif
-       __u8                    ipvs_property:1;
 
+       __u8                    ipvs_property:1;
        __u8                    inner_protocol_type:1;
        __u8                    remcsum_offload:1;
 #ifdef CONFIG_NET_SWITCHDEV
@@ -816,12 +824,6 @@ struct sk_buff {
        __u32                   priority;
        int                     skb_iif;
        __u32                   hash;
-#define PKT_VLAN_PRESENT_BIT   4       // CFI (12-th bit) in TCI
-#ifdef __BIG_ENDIAN
-#define PKT_VLAN_PRESENT_OFFSET()      offsetof(struct sk_buff, vlan_tci)
-#else
-#define PKT_VLAN_PRESENT_OFFSET()      (offsetof(struct sk_buff, vlan_tci) + 1)
-#endif
        __be16                  vlan_proto;
        __u16                   vlan_tci;
 #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS)

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index aa22bca..f3e5707 100644 (file)
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -39,6 +39,7 @@
 #define SKB_HASH       0x1234aaab
 #define SKB_QUEUE_MAP  123
 #define SKB_VLAN_TCI   0xffff
+#define SKB_VLAN_PRESENT       1
 #define SKB_DEV_IFINDEX        577
 #define SKB_DEV_TYPE   588
 
@@ -725,8 +726,8 @@ static struct bpf_test tests[] = {
                CLASSIC,
                { },
                {
-                       { 1, SKB_VLAN_TCI & ~VLAN_TAG_PRESENT },
-                       { 10, SKB_VLAN_TCI & ~VLAN_TAG_PRESENT }
+                       { 1, SKB_VLAN_TCI },
+                       { 10, SKB_VLAN_TCI }
                },
        },
        {
@@ -739,8 +740,8 @@ static struct bpf_test tests[] = {
                CLASSIC,
                { },
                {
-                       { 1, !!(SKB_VLAN_TCI & VLAN_TAG_PRESENT) },
-                       { 10, !!(SKB_VLAN_TCI & VLAN_TAG_PRESENT) }
+                       { 1, SKB_VLAN_PRESENT },
+                       { 10, SKB_VLAN_PRESENT }
                },
        },
        {
@@ -5289,8 +5290,8 @@ static struct bpf_test tests[] = {
 #endif
                { },
                {
-                       {  1, !!(SKB_VLAN_TCI & VLAN_TAG_PRESENT) },
-                       { 10, !!(SKB_VLAN_TCI & VLAN_TAG_PRESENT) }
+                       {  1, SKB_VLAN_PRESENT },
+                       { 10, SKB_VLAN_PRESENT }
                },
                .fill_helper = bpf_fill_maxinsns6,
                .expected_errcode = -ENOTSUPP,
@@ -6493,6 +6494,7 @@ static struct sk_buff *populate_skb(char *buf, int size)
        skb->hash = SKB_HASH;
        skb->queue_mapping = SKB_QUEUE_MAP;
        skb->vlan_tci = SKB_VLAN_TCI;
+       skb->vlan_present = SKB_VLAN_PRESENT;
        skb->vlan_proto = htons(ETH_P_IP);
        dev_net_set(&dev, &init_net);
        skb->dev = &dev;

diff --git a/net/core/filter.c b/net/core/filter.c
index c151b90..10acbc0 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -301,9 +301,6 @@ static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
                /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
                *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
                                      offsetof(struct sk_buff, vlan_tci));
-#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());
@@ -6152,9 +6149,6 @@ static u32 bpf_convert_ctx_access(enum bpf_access_type type,
                *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
                                      bpf_target_off(struct sk_buff, vlan_tci, 2,
                                                     target_size));
-#ifdef VLAN_TAG_PRESENT
-               *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, ~VLAN_TAG_PRESENT);
-#endif
                break;
 
        case offsetof(struct __sk_buff, cb[0]) ...