[thirdparty/kernel/stable.git] / include / net / erspan.h

#ifndef __LINUX_ERSPAN_H
#define __LINUX_ERSPAN_H

/*
 * GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes
 *       0                   1                   2                   3
 *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |0|0|0|1|0|00000|000000000|00000|    Protocol Type for ERSPAN   |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |      Sequence Number (increments per packet per session)      |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *  Note that in the above GRE header [RFC1701] out of the C, R, K, S,
 *  s, Recur, Flags, Version fields only S (bit 03) is set to 1. The
 *  other fields are set to zero, so only a sequence number follows.
 *
 *  ERSPAN Version 1 (Type II) header (8 octets [42:49])
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Ver  |          VLAN         | COS | En|T|    Session ID     |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |      Reserved         |                  Index                |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *
 *  ERSPAN Version 2 (Type III) header (12 octets [42:49])
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Ver  |          VLAN         | COS |BSO|T|     Session ID    |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                          Timestamp                            |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |             SGT               |P|    FT   |   Hw ID   |D|Gra|O|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *      Platform Specific SubHeader (8 octets, optional)
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Platf ID |               Platform Specific Info              |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                  Platform Specific Info                       |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB
 */

#include <uapi/linux/erspan.h>

#define ERSPAN_VERSION	0x1	/* ERSPAN type II */
#define VER_MASK	0xf000
#define VLAN_MASK	0x0fff
#define COS_MASK	0xe000
#define EN_MASK		0x1800
#define T_MASK		0x0400
#define ID_MASK		0x03ff
#define INDEX_MASK	0xfffff

#define ERSPAN_VERSION2	0x2	/* ERSPAN type III*/
#define BSO_MASK	EN_MASK
#define SGT_MASK	0xffff0000
#define P_MASK		0x8000
#define FT_MASK		0x7c00
#define HWID_MASK	0x03f0
#define DIR_MASK	0x0008
#define GRA_MASK	0x0006
#define O_MASK		0x0001

#define HWID_OFFSET    4
#define DIR_OFFSET     3

enum erspan_encap_type {
	ERSPAN_ENCAP_NOVLAN = 0x0,	/* originally without VLAN tag */
	ERSPAN_ENCAP_ISL = 0x1,		/* originally ISL encapsulated */
	ERSPAN_ENCAP_8021Q = 0x2,	/* originally 802.1Q encapsulated */
	ERSPAN_ENCAP_INFRAME = 0x3,	/* VLAN tag perserved in frame */
};

#define ERSPAN_V1_MDSIZE	4
#define ERSPAN_V2_MDSIZE	8

struct erspan_base_hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__u8	vlan_upper:4,
		ver:4;
	__u8	vlan:8;
	__u8	session_id_upper:2,
		t:1,
		en:2,
		cos:3;
	__u8	session_id:8;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__u8	ver: 4,
		vlan_upper:4;
	__u8	vlan:8;
	__u8	cos:3,
		en:2,
		t:1,
		session_id_upper:2;
	__u8	session_id:8;
#else
#error "Please fix <asm/byteorder.h>"
#endif
};

static inline void set_session_id(struct erspan_base_hdr *ershdr, u16 id)
{
	ershdr->session_id = id & 0xff;
	ershdr->session_id_upper = (id >> 8) & 0x3;
}

static inline u16 get_session_id(const struct erspan_base_hdr *ershdr)
{
	return (ershdr->session_id_upper << 8) + ershdr->session_id;
}

static inline void set_vlan(struct erspan_base_hdr *ershdr, u16 vlan)
{
	ershdr->vlan = vlan & 0xff;
	ershdr->vlan_upper = (vlan >> 8) & 0xf;
}

static inline u16 get_vlan(const struct erspan_base_hdr *ershdr)
{
	return (ershdr->vlan_upper << 8) + ershdr->vlan;
}

static inline void set_hwid(struct erspan_md2 *md2, u8 hwid)
{
	md2->hwid = hwid & 0xf;
	md2->hwid_upper = (hwid >> 4) & 0x3;
}

static inline u8 get_hwid(const struct erspan_md2 *md2)
{
	return (md2->hwid_upper << 4) + md2->hwid;
}

static inline int erspan_hdr_len(int version)
{
	return sizeof(struct erspan_base_hdr) +
	       (version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE);
}

static inline u8 tos_to_cos(u8 tos)
{
	u8 dscp, cos;

	dscp = tos >> 2;
	cos = dscp >> 3;
	return cos;
}

static inline void erspan_build_header(struct sk_buff *skb,
				u32 id, u32 index,
				bool truncate, bool is_ipv4)
{
	struct ethhdr *eth = (struct ethhdr *)skb->data;
	enum erspan_encap_type enc_type;
	struct erspan_base_hdr *ershdr;
	struct qtag_prefix {
		__be16 eth_type;
		__be16 tci;
	} *qp;
	u16 vlan_tci = 0;
	u8 tos;
	__be32 *idx;

	tos = is_ipv4 ? ip_hdr(skb)->tos :
			(ipv6_hdr(skb)->priority << 4) +
			(ipv6_hdr(skb)->flow_lbl[0] >> 4);

	enc_type = ERSPAN_ENCAP_NOVLAN;

	/* If mirrored packet has vlan tag, extract tci and
	 *  perserve vlan header in the mirrored frame.
	 */
	if (eth->h_proto == htons(ETH_P_8021Q)) {
		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);
		vlan_tci = ntohs(qp->tci);
		enc_type = ERSPAN_ENCAP_INFRAME;
	}

	skb_push(skb, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
	ershdr = (struct erspan_base_hdr *)skb->data;
	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);

	/* Build base header */
	ershdr->ver = ERSPAN_VERSION;
	ershdr->cos = tos_to_cos(tos);
	ershdr->en = enc_type;
	ershdr->t = truncate;
	set_vlan(ershdr, vlan_tci);
	set_session_id(ershdr, id);

	/* Build metadata */
	idx = (__be32 *)(ershdr + 1);
	*idx = htonl(index & INDEX_MASK);
}

/* ERSPAN GRA: timestamp granularity
 *   00b --> granularity = 100 microseconds
 *   01b --> granularity = 100 nanoseconds
 *   10b --> granularity = IEEE 1588
 * Here we only support 100 microseconds.
 */
static inline __be32 erspan_get_timestamp(void)
{
	u64 h_usecs;
	ktime_t kt;

	kt = ktime_get_real();
	h_usecs = ktime_divns(kt, 100 * NSEC_PER_USEC);

	/* ERSPAN base header only has 32-bit,
	 * so it wraps around 4 days.
	 */
	return htonl((u32)h_usecs);
}

/* ERSPAN BSO (Bad/Short/Oversized), see RFC1757
 *   00b --> Good frame with no error, or unknown integrity
 *   01b --> Payload is a Short Frame
 *   10b --> Payload is an Oversized Frame
 *   11b --> Payload is a Bad Frame with CRC or Alignment Error
 */
enum erspan_bso {
	BSO_NOERROR = 0x0,
	BSO_SHORT = 0x1,
	BSO_OVERSIZED = 0x2,
	BSO_BAD = 0x3,
};

static inline u8 erspan_detect_bso(struct sk_buff *skb)
{
	/* BSO_BAD is not handled because the frame CRC
	 * or alignment error information is in FCS.
	 */
	if (skb->len < ETH_ZLEN)
		return BSO_SHORT;

	if (skb->len > ETH_FRAME_LEN)
		return BSO_OVERSIZED;

	return BSO_NOERROR;
}

static inline void erspan_build_header_v2(struct sk_buff *skb,
					  u32 id, u8 direction, u16 hwid,
					  bool truncate, bool is_ipv4)
{
	struct ethhdr *eth = (struct ethhdr *)skb->data;
	struct erspan_base_hdr *ershdr;
	struct erspan_md2 *md2;
	struct qtag_prefix {
		__be16 eth_type;
		__be16 tci;
	} *qp;
	u16 vlan_tci = 0;
	u8 gra = 0; /* 100 usec */
	u8 bso = 0; /* Bad/Short/Oversized */
	u8 sgt = 0;
	u8 tos;

	tos = is_ipv4 ? ip_hdr(skb)->tos :
			(ipv6_hdr(skb)->priority << 4) +
			(ipv6_hdr(skb)->flow_lbl[0] >> 4);

	/* Unlike v1, v2 does not have En field,
	 * so only extract vlan tci field.
	 */
	if (eth->h_proto == htons(ETH_P_8021Q)) {
		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);
		vlan_tci = ntohs(qp->tci);
	}

	bso = erspan_detect_bso(skb);
	skb_push(skb, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	ershdr = (struct erspan_base_hdr *)skb->data;
	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);

	/* Build base header */
	ershdr->ver = ERSPAN_VERSION2;
	ershdr->cos = tos_to_cos(tos);
	ershdr->en = bso;
	ershdr->t = truncate;
	set_vlan(ershdr, vlan_tci);
	set_session_id(ershdr, id);

	/* Build metadata */
	md2 = (struct erspan_md2 *)(ershdr + 1);
	md2->timestamp = erspan_get_timestamp();
	md2->sgt = htons(sgt);
	md2->p = 1;
	md2->ft = 0;
	md2->dir = direction;
	md2->gra = gra;
	md2->o = 0;
	set_hwid(md2, hwid);
}

#endif
Commit	Line	Data
84e54fe0 WT	1	#ifndef __LINUX_ERSPAN_H
	2	#define __LINUX_ERSPAN_H
	3
	4	/*
	5	* GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes
	6	* 0 1 2 3
	7	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	8	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	9	* \|0\|0\|0\|1\|0\|00000\|000000000\|00000\| Protocol Type for ERSPAN \|
	10	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	11	* \| Sequence Number (increments per packet per session) \|
	12	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	13	*
	14	* Note that in the above GRE header [RFC1701] out of the C, R, K, S,
	15	* s, Recur, Flags, Version fields only S (bit 03) is set to 1. The
	16	* other fields are set to zero, so only a sequence number follows.
	17	*
1d7e2ed2	18	* ERSPAN Version 1 (Type II) header (8 octets [42:49])
84e54fe0 WT	19	* 0 1 2 3
	20	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	21	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	22	* \| Ver \| VLAN \| COS \| En\|T\| Session ID \|
	23	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	24	* \| Reserved \| Index \|
	25	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	26	*
f551c91d WT	27	*
	28	* ERSPAN Version 2 (Type III) header (12 octets [42:49])
	29	* 0 1 2 3
	30	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	31	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	32	* \| Ver \| VLAN \| COS \|BSO\|T\| Session ID \|
	33	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	34	* \| Timestamp \|
	35	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	36	* \| SGT \|P\| FT \| Hw ID \|D\|Gra\|O\|
	37	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	38	*
	39	* Platform Specific SubHeader (8 octets, optional)
	40	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	41	* \| Platf ID \| Platform Specific Info \|
	42	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	43	* \| Platform Specific Info \|
	44	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	45	*
84e54fe0 WT	46	* GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB
	47	*/
	48
d350a823 WT	49	#include <uapi/linux/erspan.h>
d350a823 WT	50
1d7e2ed2	51	#define ERSPAN_VERSION 0x1 /* ERSPAN type II */
84e54fe0 WT	52	#define VER_MASK 0xf000
	53	#define VLAN_MASK 0x0fff
	54	#define COS_MASK 0xe000
	55	#define EN_MASK 0x1800
	56	#define T_MASK 0x0400
	57	#define ID_MASK 0x03ff
	58	#define INDEX_MASK 0xfffff
	59
f551c91d WT	60	#define ERSPAN_VERSION2 0x2 /* ERSPAN type III*/
	61	#define BSO_MASK EN_MASK
	62	#define SGT_MASK 0xffff0000
	63	#define P_MASK 0x8000
	64	#define FT_MASK 0x7c00
	65	#define HWID_MASK 0x03f0
	66	#define DIR_MASK 0x0008
	67	#define GRA_MASK 0x0006
	68	#define O_MASK 0x0001
	69
c69de58b WT	70	#define HWID_OFFSET 4
	71	#define DIR_OFFSET 3
	72
84e54fe0 WT	73	enum erspan_encap_type {
	74	ERSPAN_ENCAP_NOVLAN = 0x0, /* originally without VLAN tag */
	75	ERSPAN_ENCAP_ISL = 0x1, /* originally ISL encapsulated */
	76	ERSPAN_ENCAP_8021Q = 0x2, /* originally 802.1Q encapsulated */
	77	ERSPAN_ENCAP_INFRAME = 0x3, /* VLAN tag perserved in frame */
	78	};
	79
1d7e2ed2 WT	80	#define ERSPAN_V1_MDSIZE 4
1d7e2ed2 WT	81	#define ERSPAN_V2_MDSIZE 8
84e54fe0	82
1d7e2ed2	83	struct erspan_base_hdr {
c69de58b WT	84	#if defined(__LITTLE_ENDIAN_BITFIELD)
	85	__u8 vlan_upper:4,
	86	ver:4;
	87	__u8 vlan:8;
	88	__u8 session_id_upper:2,
	89	t:1,
	90	en:2,
	91	cos:3;
	92	__u8 session_id:8;
	93	#elif defined(__BIG_ENDIAN_BITFIELD)
	94	__u8 ver: 4,
	95	vlan_upper:4;
	96	__u8 vlan:8;
	97	__u8 cos:3,
	98	en:2,
	99	t:1,
	100	session_id_upper:2;
	101	__u8 session_id:8;
	102	#else
	103	#error "Please fix <asm/byteorder.h>"
	104	#endif
84e54fe0 WT	105	};
84e54fe0 WT	106
c69de58b WT	107	static inline void set_session_id(struct erspan_base_hdr *ershdr, u16 id)
	108	{
	109	ershdr->session_id = id & 0xff;
	110	ershdr->session_id_upper = (id >> 8) & 0x3;
	111	}
	112
	113	static inline u16 get_session_id(const struct erspan_base_hdr *ershdr)
	114	{
	115	return (ershdr->session_id_upper << 8) + ershdr->session_id;
	116	}
	117
	118	static inline void set_vlan(struct erspan_base_hdr *ershdr, u16 vlan)
	119	{
	120	ershdr->vlan = vlan & 0xff;
	121	ershdr->vlan_upper = (vlan >> 8) & 0xf;
	122	}
	123
	124	static inline u16 get_vlan(const struct erspan_base_hdr *ershdr)
	125	{
	126	return (ershdr->vlan_upper << 8) + ershdr->vlan;
	127	}
	128
	129	static inline void set_hwid(struct erspan_md2 *md2, u8 hwid)
	130	{
	131	md2->hwid = hwid & 0xf;
	132	md2->hwid_upper = (hwid >> 4) & 0x3;
	133	}
	134
	135	static inline u8 get_hwid(const struct erspan_md2 *md2)
	136	{
	137	return (md2->hwid_upper << 4) + md2->hwid;
	138	}
	139
1d7e2ed2 WT	140	static inline int erspan_hdr_len(int version)
	141	{
	142	return sizeof(struct erspan_base_hdr) +
	143	(version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE);
	144	}
	145
a3222dc9 WT	146	static inline u8 tos_to_cos(u8 tos)
	147	{
	148	u8 dscp, cos;
	149
	150	dscp = tos >> 2;
	151	cos = dscp >> 3;
	152	return cos;
	153	}
	154
	155	static inline void erspan_build_header(struct sk_buff *skb,
c69de58b	156	u32 id, u32 index,
a3222dc9 WT	157	bool truncate, bool is_ipv4)
a3222dc9 WT	158	{
b423d13c	159	struct ethhdr eth = (struct ethhdr )skb->data;
a3222dc9	160	enum erspan_encap_type enc_type;
1d7e2ed2	161	struct erspan_base_hdr *ershdr;
a3222dc9 WT	162	struct qtag_prefix {
	163	__be16 eth_type;
	164	__be16 tci;
	165	} *qp;
	166	u16 vlan_tci = 0;
	167	u8 tos;
3df19283	168	__be32 *idx;
a3222dc9 WT	169
	170	tos = is_ipv4 ? ip_hdr(skb)->tos :
	171	(ipv6_hdr(skb)->priority << 4) +
	172	(ipv6_hdr(skb)->flow_lbl[0] >> 4);
	173
	174	enc_type = ERSPAN_ENCAP_NOVLAN;
	175
	176	/* If mirrored packet has vlan tag, extract tci and
	177	* perserve vlan header in the mirrored frame.
	178	*/
	179	if (eth->h_proto == htons(ETH_P_8021Q)) {
	180	qp = (struct qtag_prefix )(skb->data + 2 ETH_ALEN);
	181	vlan_tci = ntohs(qp->tci);
	182	enc_type = ERSPAN_ENCAP_INFRAME;
	183	}
	184
1d7e2ed2 WT	185	skb_push(skb, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
	186	ershdr = (struct erspan_base_hdr *)skb->data;
	187	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
a3222dc9	188
1d7e2ed2	189	/* Build base header */
c69de58b WT	190	ershdr->ver = ERSPAN_VERSION;
	191	ershdr->cos = tos_to_cos(tos);
	192	ershdr->en = enc_type;
	193	ershdr->t = truncate;
	194	set_vlan(ershdr, vlan_tci);
	195	set_session_id(ershdr, id);
1d7e2ed2 WT	196
1d7e2ed2 WT	197	/* Build metadata */
3df19283 WT	198	idx = (__be32 *)(ershdr + 1);
3df19283 WT	199	*idx = htonl(index & INDEX_MASK);
a3222dc9 WT	200	}
a3222dc9 WT	201
f551c91d WT	202	/* ERSPAN GRA: timestamp granularity
	203	* 00b --> granularity = 100 microseconds
	204	* 01b --> granularity = 100 nanoseconds
	205	* 10b --> granularity = IEEE 1588
	206	* Here we only support 100 microseconds.
	207	*/
	208	static inline __be32 erspan_get_timestamp(void)
	209	{
	210	u64 h_usecs;
	211	ktime_t kt;
	212
	213	kt = ktime_get_real();
	214	h_usecs = ktime_divns(kt, 100 * NSEC_PER_USEC);
	215
	216	/* ERSPAN base header only has 32-bit,
	217	* so it wraps around 4 days.
	218	*/
	219	return htonl((u32)h_usecs);
	220	}
	221
d48f1958 WT	222	/* ERSPAN BSO (Bad/Short/Oversized), see RFC1757
	223	* 00b --> Good frame with no error, or unknown integrity
	224	* 01b --> Payload is a Short Frame
	225	* 10b --> Payload is an Oversized Frame
	226	* 11b --> Payload is a Bad Frame with CRC or Alignment Error
	227	*/
	228	enum erspan_bso {
	229	BSO_NOERROR = 0x0,
	230	BSO_SHORT = 0x1,
	231	BSO_OVERSIZED = 0x2,
	232	BSO_BAD = 0x3,
	233	};
	234
	235	static inline u8 erspan_detect_bso(struct sk_buff *skb)
	236	{
	237	/* BSO_BAD is not handled because the frame CRC
	238	* or alignment error information is in FCS.
	239	*/
	240	if (skb->len < ETH_ZLEN)
	241	return BSO_SHORT;
	242
	243	if (skb->len > ETH_FRAME_LEN)
	244	return BSO_OVERSIZED;
	245
	246	return BSO_NOERROR;
	247	}
	248
f551c91d	249	static inline void erspan_build_header_v2(struct sk_buff *skb,
c69de58b	250	u32 id, u8 direction, u16 hwid,
f551c91d WT	251	bool truncate, bool is_ipv4)
f551c91d WT	252	{
b423d13c	253	struct ethhdr eth = (struct ethhdr )skb->data;
f551c91d	254	struct erspan_base_hdr *ershdr;
3df19283	255	struct erspan_md2 *md2;
f551c91d WT	256	struct qtag_prefix {
	257	__be16 eth_type;
	258	__be16 tci;
	259	} *qp;
	260	u16 vlan_tci = 0;
f551c91d WT	261	u8 gra = 0; /* 100 usec */
	262	u8 bso = 0; /* Bad/Short/Oversized */
	263	u8 sgt = 0;
	264	u8 tos;
	265
	266	tos = is_ipv4 ? ip_hdr(skb)->tos :
	267	(ipv6_hdr(skb)->priority << 4) +
	268	(ipv6_hdr(skb)->flow_lbl[0] >> 4);
	269
	270	/* Unlike v1, v2 does not have En field,
	271	* so only extract vlan tci field.
	272	*/
	273	if (eth->h_proto == htons(ETH_P_8021Q)) {
	274	qp = (struct qtag_prefix )(skb->data + 2 ETH_ALEN);
	275	vlan_tci = ntohs(qp->tci);
	276	}
	277
d48f1958	278	bso = erspan_detect_bso(skb);
f551c91d WT	279	skb_push(skb, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	280	ershdr = (struct erspan_base_hdr *)skb->data;
	281	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	282
	283	/* Build base header */
c69de58b WT	284	ershdr->ver = ERSPAN_VERSION2;
	285	ershdr->cos = tos_to_cos(tos);
	286	ershdr->en = bso;
	287	ershdr->t = truncate;
	288	set_vlan(ershdr, vlan_tci);
	289	set_session_id(ershdr, id);
f551c91d WT	290
f551c91d WT	291	/* Build metadata */
3df19283 WT	292	md2 = (struct erspan_md2 *)(ershdr + 1);
	293	md2->timestamp = erspan_get_timestamp();
	294	md2->sgt = htons(sgt);
	295	md2->p = 1;
	296	md2->ft = 0;
	297	md2->dir = direction;
	298	md2->gra = gra;
	299	md2->o = 0;
	300	set_hwid(md2, hwid);
f551c91d WT	301	}
f551c91d WT	302
84e54fe0	303	#endif