1/*-
2 *   BSD LICENSE
3 *
4 *   Copyright(c) 2016 Intel Corporation. All rights reserved.
5 *   All rights reserved.
6 *
7 *   Redistribution and use in source and binary forms, with or without
8 *   modification, are permitted provided that the following conditions
9 *   are met:
10 *
11 *     * Redistributions of source code must retain the above copyright
12 *       notice, this list of conditions and the following disclaimer.
13 *     * Redistributions in binary form must reproduce the above copyright
14 *       notice, this list of conditions and the following disclaimer in
15 *       the documentation and/or other materials provided with the
16 *       distribution.
17 *     * Neither the name of Intel Corporation nor the names of its
18 *       contributors may be used to endorse or promote products derived
19 *       from this software without specific prior written permission.
20 *
21 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34
35#ifndef _L3FWD_COMMON_H_
36#define _L3FWD_COMMON_H_
37
38#include "l3fwd.h"
39
40#ifdef DO_RFC_1812_CHECKS
41
42#define	IPV4_MIN_VER_IHL	0x45
43#define	IPV4_MAX_VER_IHL	0x4f
44#define	IPV4_MAX_VER_IHL_DIFF	(IPV4_MAX_VER_IHL - IPV4_MIN_VER_IHL)
45
46/* Minimum value of IPV4 total length (20B) in network byte order. */
47#define	IPV4_MIN_LEN_BE	(sizeof(struct ipv4_hdr) << 8)
48
49/*
50 * From http://www.rfc-editor.org/rfc/rfc1812.txt section 5.2.2:
51 * - The IP version number must be 4.
52 * - The IP header length field must be large enough to hold the
53 *    minimum length legal IP datagram (20 bytes = 5 words).
54 * - The IP total length field must be large enough to hold the IP
55 *   datagram header, whose length is specified in the IP header length
56 *   field.
57 * If we encounter invalid IPV4 packet, then set destination port for it
58 * to BAD_PORT value.
59 */
60static inline __attribute__((always_inline)) void
61rfc1812_process(struct ipv4_hdr *ipv4_hdr, uint16_t *dp, uint32_t ptype)
62{
63	uint8_t ihl;
64
65	if (RTE_ETH_IS_IPV4_HDR(ptype)) {
66		ihl = ipv4_hdr->version_ihl - IPV4_MIN_VER_IHL;
67
68		ipv4_hdr->time_to_live--;
69		ipv4_hdr->hdr_checksum++;
70
71		if (ihl > IPV4_MAX_VER_IHL_DIFF ||
72				((uint8_t)ipv4_hdr->total_length == 0 &&
73				ipv4_hdr->total_length < IPV4_MIN_LEN_BE))
74			dp[0] = BAD_PORT;
75
76	}
77}
78
79#else
80#define	rfc1812_process(mb, dp, ptype)	do { } while (0)
81#endif /* DO_RFC_1812_CHECKS */
82
83/*
84 * Update source and destination MAC addresses in the ethernet header.
85 * Perform RFC1812 checks and updates for IPV4 packets.
86 */
87static inline void
88processx4_step3(struct rte_mbuf *pkt[FWDSTEP], uint16_t dst_port[FWDSTEP])
89{
90	__m128i te[FWDSTEP];
91	__m128i ve[FWDSTEP];
92	__m128i *p[FWDSTEP];
93
94	p[0] = rte_pktmbuf_mtod(pkt[0], __m128i *);
95	p[1] = rte_pktmbuf_mtod(pkt[1], __m128i *);
96	p[2] = rte_pktmbuf_mtod(pkt[2], __m128i *);
97	p[3] = rte_pktmbuf_mtod(pkt[3], __m128i *);
98
99	ve[0] = val_eth[dst_port[0]];
100	te[0] = _mm_loadu_si128(p[0]);
101
102	ve[1] = val_eth[dst_port[1]];
103	te[1] = _mm_loadu_si128(p[1]);
104
105	ve[2] = val_eth[dst_port[2]];
106	te[2] = _mm_loadu_si128(p[2]);
107
108	ve[3] = val_eth[dst_port[3]];
109	te[3] = _mm_loadu_si128(p[3]);
110
111	/* Update first 12 bytes, keep rest bytes intact. */
112	te[0] =  _mm_blend_epi16(te[0], ve[0], MASK_ETH);
113	te[1] =  _mm_blend_epi16(te[1], ve[1], MASK_ETH);
114	te[2] =  _mm_blend_epi16(te[2], ve[2], MASK_ETH);
115	te[3] =  _mm_blend_epi16(te[3], ve[3], MASK_ETH);
116
117	_mm_storeu_si128(p[0], te[0]);
118	_mm_storeu_si128(p[1], te[1]);
119	_mm_storeu_si128(p[2], te[2]);
120	_mm_storeu_si128(p[3], te[3]);
121
122	rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[0] + 1),
123		&dst_port[0], pkt[0]->packet_type);
124	rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[1] + 1),
125		&dst_port[1], pkt[1]->packet_type);
126	rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[2] + 1),
127		&dst_port[2], pkt[2]->packet_type);
128	rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[3] + 1),
129		&dst_port[3], pkt[3]->packet_type);
130}
131
132/*
133 * We group consecutive packets with the same destionation port into one burst.
134 * To avoid extra latency this is done together with some other packet
135 * processing, but after we made a final decision about packet's destination.
136 * To do this we maintain:
137 * pnum - array of number of consecutive packets with the same dest port for
138 * each packet in the input burst.
139 * lp - pointer to the last updated element in the pnum.
140 * dlp - dest port value lp corresponds to.
141 */
142
143#define	GRPSZ	(1 << FWDSTEP)
144#define	GRPMSK	(GRPSZ - 1)
145
146#define GROUP_PORT_STEP(dlp, dcp, lp, pn, idx)	do { \
147	if (likely((dlp) == (dcp)[(idx)])) {             \
148		(lp)[0]++;                                   \
149	} else {                                         \
150		(dlp) = (dcp)[idx];                          \
151		(lp) = (pn) + (idx);                         \
152		(lp)[0] = 1;                                 \
153	}                                                \
154} while (0)
155
156/*
157 * Group consecutive packets with the same destination port in bursts of 4.
158 * Suppose we have array of destionation ports:
159 * dst_port[] = {a, b, c, d,, e, ... }
160 * dp1 should contain: <a, b, c, d>, dp2: <b, c, d, e>.
161 * We doing 4 comparisions at once and the result is 4 bit mask.
162 * This mask is used as an index into prebuild array of pnum values.
163 */
164static inline uint16_t *
165port_groupx4(uint16_t pn[FWDSTEP + 1], uint16_t *lp, __m128i dp1, __m128i dp2)
166{
167	static const struct {
168		uint64_t pnum; /* prebuild 4 values for pnum[]. */
169		int32_t  idx;  /* index for new last updated elemnet. */
170		uint16_t lpv;  /* add value to the last updated element. */
171	} gptbl[GRPSZ] = {
172	{
173		/* 0: a != b, b != c, c != d, d != e */
174		.pnum = UINT64_C(0x0001000100010001),
175		.idx = 4,
176		.lpv = 0,
177	},
178	{
179		/* 1: a == b, b != c, c != d, d != e */
180		.pnum = UINT64_C(0x0001000100010002),
181		.idx = 4,
182		.lpv = 1,
183	},
184	{
185		/* 2: a != b, b == c, c != d, d != e */
186		.pnum = UINT64_C(0x0001000100020001),
187		.idx = 4,
188		.lpv = 0,
189	},
190	{
191		/* 3: a == b, b == c, c != d, d != e */
192		.pnum = UINT64_C(0x0001000100020003),
193		.idx = 4,
194		.lpv = 2,
195	},
196	{
197		/* 4: a != b, b != c, c == d, d != e */
198		.pnum = UINT64_C(0x0001000200010001),
199		.idx = 4,
200		.lpv = 0,
201	},
202	{
203		/* 5: a == b, b != c, c == d, d != e */
204		.pnum = UINT64_C(0x0001000200010002),
205		.idx = 4,
206		.lpv = 1,
207	},
208	{
209		/* 6: a != b, b == c, c == d, d != e */
210		.pnum = UINT64_C(0x0001000200030001),
211		.idx = 4,
212		.lpv = 0,
213	},
214	{
215		/* 7: a == b, b == c, c == d, d != e */
216		.pnum = UINT64_C(0x0001000200030004),
217		.idx = 4,
218		.lpv = 3,
219	},
220	{
221		/* 8: a != b, b != c, c != d, d == e */
222		.pnum = UINT64_C(0x0002000100010001),
223		.idx = 3,
224		.lpv = 0,
225	},
226	{
227		/* 9: a == b, b != c, c != d, d == e */
228		.pnum = UINT64_C(0x0002000100010002),
229		.idx = 3,
230		.lpv = 1,
231	},
232	{
233		/* 0xa: a != b, b == c, c != d, d == e */
234		.pnum = UINT64_C(0x0002000100020001),
235		.idx = 3,
236		.lpv = 0,
237	},
238	{
239		/* 0xb: a == b, b == c, c != d, d == e */
240		.pnum = UINT64_C(0x0002000100020003),
241		.idx = 3,
242		.lpv = 2,
243	},
244	{
245		/* 0xc: a != b, b != c, c == d, d == e */
246		.pnum = UINT64_C(0x0002000300010001),
247		.idx = 2,
248		.lpv = 0,
249	},
250	{
251		/* 0xd: a == b, b != c, c == d, d == e */
252		.pnum = UINT64_C(0x0002000300010002),
253		.idx = 2,
254		.lpv = 1,
255	},
256	{
257		/* 0xe: a != b, b == c, c == d, d == e */
258		.pnum = UINT64_C(0x0002000300040001),
259		.idx = 1,
260		.lpv = 0,
261	},
262	{
263		/* 0xf: a == b, b == c, c == d, d == e */
264		.pnum = UINT64_C(0x0002000300040005),
265		.idx = 0,
266		.lpv = 4,
267	},
268	};
269
270	union {
271		uint16_t u16[FWDSTEP + 1];
272		uint64_t u64;
273	} *pnum = (void *)pn;
274
275	int32_t v;
276
277	dp1 = _mm_cmpeq_epi16(dp1, dp2);
278	dp1 = _mm_unpacklo_epi16(dp1, dp1);
279	v = _mm_movemask_ps((__m128)dp1);
280
281	/* update last port counter. */
282	lp[0] += gptbl[v].lpv;
283
284	/* if dest port value has changed. */
285	if (v != GRPMSK) {
286		pnum->u64 = gptbl[v].pnum;
287		pnum->u16[FWDSTEP] = 1;
288		lp = pnum->u16 + gptbl[v].idx;
289	}
290
291	return lp;
292}
293
294/**
295 * Process one packet:
296 * Update source and destination MAC addresses in the ethernet header.
297 * Perform RFC1812 checks and updates for IPV4 packets.
298 */
299static inline void
300process_packet(struct rte_mbuf *pkt, uint16_t *dst_port)
301{
302	struct ether_hdr *eth_hdr;
303	__m128i te, ve;
304
305	eth_hdr = rte_pktmbuf_mtod(pkt, struct ether_hdr *);
306
307	te = _mm_loadu_si128((__m128i *)eth_hdr);
308	ve = val_eth[dst_port[0]];
309
310	rfc1812_process((struct ipv4_hdr *)(eth_hdr + 1), dst_port,
311			pkt->packet_type);
312
313	te =  _mm_blend_epi16(te, ve, MASK_ETH);
314	_mm_storeu_si128((__m128i *)eth_hdr, te);
315}
316
317static inline __attribute__((always_inline)) void
318send_packetsx4(struct lcore_conf *qconf, uint8_t port, struct rte_mbuf *m[],
319		uint32_t num)
320{
321	uint32_t len, j, n;
322
323	len = qconf->tx_mbufs[port].len;
324
325	/*
326	 * If TX buffer for that queue is empty, and we have enough packets,
327	 * then send them straightway.
328	 */
329	if (num >= MAX_TX_BURST && len == 0) {
330		n = rte_eth_tx_burst(port, qconf->tx_queue_id[port], m, num);
331		if (unlikely(n < num)) {
332			do {
333				rte_pktmbuf_free(m[n]);
334			} while (++n < num);
335		}
336		return;
337	}
338
339	/*
340	 * Put packets into TX buffer for that queue.
341	 */
342
343	n = len + num;
344	n = (n > MAX_PKT_BURST) ? MAX_PKT_BURST - len : num;
345
346	j = 0;
347	switch (n % FWDSTEP) {
348	while (j < n) {
349	case 0:
350		qconf->tx_mbufs[port].m_table[len + j] = m[j];
351		j++;
352	case 3:
353		qconf->tx_mbufs[port].m_table[len + j] = m[j];
354		j++;
355	case 2:
356		qconf->tx_mbufs[port].m_table[len + j] = m[j];
357		j++;
358	case 1:
359		qconf->tx_mbufs[port].m_table[len + j] = m[j];
360		j++;
361	}
362	}
363
364	len += n;
365
366	/* enough pkts to be sent */
367	if (unlikely(len == MAX_PKT_BURST)) {
368
369		send_burst(qconf, MAX_PKT_BURST, port);
370
371		/* copy rest of the packets into the TX buffer. */
372		len = num - n;
373		j = 0;
374		switch (len % FWDSTEP) {
375		while (j < len) {
376		case 0:
377			qconf->tx_mbufs[port].m_table[j] = m[n + j];
378			j++;
379		case 3:
380			qconf->tx_mbufs[port].m_table[j] = m[n + j];
381			j++;
382		case 2:
383			qconf->tx_mbufs[port].m_table[j] = m[n + j];
384			j++;
385		case 1:
386			qconf->tx_mbufs[port].m_table[j] = m[n + j];
387			j++;
388		}
389		}
390	}
391
392	qconf->tx_mbufs[port].len = len;
393}
394
395/**
396 * Send packets burst from pkts_burst to the ports in dst_port array
397 */
398static inline __attribute__((always_inline)) void
399send_packets_multi(struct lcore_conf *qconf, struct rte_mbuf **pkts_burst,
400		uint16_t dst_port[MAX_PKT_BURST], int nb_rx)
401{
402	int32_t k;
403	int j = 0;
404	uint16_t dlp;
405	uint16_t *lp;
406	uint16_t pnum[MAX_PKT_BURST + 1];
407
408	/*
409	 * Finish packet processing and group consecutive
410	 * packets with the same destination port.
411	 */
412	k = RTE_ALIGN_FLOOR(nb_rx, FWDSTEP);
413	if (k != 0) {
414		__m128i dp1, dp2;
415
416		lp = pnum;
417		lp[0] = 1;
418
419		processx4_step3(pkts_burst, dst_port);
420
421		/* dp1: <d[0], d[1], d[2], d[3], ... > */
422		dp1 = _mm_loadu_si128((__m128i *)dst_port);
423
424		for (j = FWDSTEP; j != k; j += FWDSTEP) {
425			processx4_step3(&pkts_burst[j], &dst_port[j]);
426
427			/*
428			 * dp2:
429			 * <d[j-3], d[j-2], d[j-1], d[j], ... >
430			 */
431			dp2 = _mm_loadu_si128((__m128i *)
432					&dst_port[j - FWDSTEP + 1]);
433			lp  = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
434
435			/*
436			 * dp1:
437			 * <d[j], d[j+1], d[j+2], d[j+3], ... >
438			 */
439			dp1 = _mm_srli_si128(dp2, (FWDSTEP - 1) *
440						sizeof(dst_port[0]));
441		}
442
443		/*
444		 * dp2: <d[j-3], d[j-2], d[j-1], d[j-1], ... >
445		 */
446		dp2 = _mm_shufflelo_epi16(dp1, 0xf9);
447		lp  = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
448
449		/*
450		 * remove values added by the last repeated
451		 * dst port.
452		 */
453		lp[0]--;
454		dlp = dst_port[j - 1];
455	} else {
456		/* set dlp and lp to the never used values. */
457		dlp = BAD_PORT - 1;
458		lp = pnum + MAX_PKT_BURST;
459	}
460
461	/* Process up to last 3 packets one by one. */
462	switch (nb_rx % FWDSTEP) {
463	case 3:
464		process_packet(pkts_burst[j], dst_port + j);
465		GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
466		j++;
467	case 2:
468		process_packet(pkts_burst[j], dst_port + j);
469		GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
470		j++;
471	case 1:
472		process_packet(pkts_burst[j], dst_port + j);
473		GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
474		j++;
475	}
476
477	/*
478	 * Send packets out, through destination port.
479	 * Consecutive packets with the same destination port
480	 * are already grouped together.
481	 * If destination port for the packet equals BAD_PORT,
482	 * then free the packet without sending it out.
483	 */
484	for (j = 0; j < nb_rx; j += k) {
485
486		int32_t m;
487		uint16_t pn;
488
489		pn = dst_port[j];
490		k = pnum[j];
491
492		if (likely(pn != BAD_PORT))
493			send_packetsx4(qconf, pn, pkts_burst + j, k);
494		else
495			for (m = j; m != j + k; m++)
496				rte_pktmbuf_free(pkts_burst[m]);
497
498	}
499}
500
501#endif /* _L3FWD_COMMON_H_ */
502