xref: /dpdk/drivers/net/mlx4/mlx4_rxtx.c (revision 089e5ed727a15da2729cfee9b63533dd120bd04c)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2017 6WIND S.A.
3  * Copyright 2017 Mellanox Technologies, Ltd
4  */
5 
6 /**
7  * @file
8  * Data plane functions for mlx4 driver.
9  */
10 
11 #include <assert.h>
12 #include <stdbool.h>
13 #include <stdint.h>
14 #include <string.h>
15 
16 /* Verbs headers do not support -pedantic. */
17 #ifdef PEDANTIC
18 #pragma GCC diagnostic ignored "-Wpedantic"
19 #endif
20 #include <infiniband/verbs.h>
21 #ifdef PEDANTIC
22 #pragma GCC diagnostic error "-Wpedantic"
23 #endif
24 
25 #include <rte_branch_prediction.h>
26 #include <rte_common.h>
27 #include <rte_io.h>
28 #include <rte_mbuf.h>
29 #include <rte_mempool.h>
30 #include <rte_prefetch.h>
31 
32 #include "mlx4.h"
33 #include "mlx4_prm.h"
34 #include "mlx4_rxtx.h"
35 #include "mlx4_utils.h"
36 
37 /**
38  * Pointer-value pair structure used in tx_post_send for saving the first
39  * DWORD (32 byte) of a TXBB.
40  */
41 struct pv {
42 	union {
43 		volatile struct mlx4_wqe_data_seg *dseg;
44 		volatile uint32_t *dst;
45 	};
46 	uint32_t val;
47 };
48 
49 /** A helper structure for TSO packet handling. */
50 struct tso_info {
51 	/** Pointer to the array of saved first DWORD (32 byte) of a TXBB. */
52 	struct pv *pv;
53 	/** Current entry in the pv array. */
54 	int pv_counter;
55 	/** Total size of the WQE including padding. */
56 	uint32_t wqe_size;
57 	/** Size of TSO header to prepend to each packet to send. */
58 	uint16_t tso_header_size;
59 	/** Total size of the TSO segment in the WQE. */
60 	uint16_t wqe_tso_seg_size;
61 	/** Raw WQE size in units of 16 Bytes and without padding. */
62 	uint8_t fence_size;
63 };
64 
65 /** A table to translate Rx completion flags to packet type. */
66 uint32_t mlx4_ptype_table[0x100] __rte_cache_aligned = {
67 	/*
68 	 * The index to the array should have:
69 	 *  bit[7] - MLX4_CQE_L2_TUNNEL
70 	 *  bit[6] - MLX4_CQE_L2_TUNNEL_IPV4
71 	 *  bit[5] - MLX4_CQE_STATUS_UDP
72 	 *  bit[4] - MLX4_CQE_STATUS_TCP
73 	 *  bit[3] - MLX4_CQE_STATUS_IPV4OPT
74 	 *  bit[2] - MLX4_CQE_STATUS_IPV6
75 	 *  bit[1] - MLX4_CQE_STATUS_IPF
76 	 *  bit[0] - MLX4_CQE_STATUS_IPV4
77 	 * giving a total of up to 256 entries.
78 	 */
79 	/* L2 */
80 	[0x00] = RTE_PTYPE_L2_ETHER,
81 	/* L3 */
82 	[0x01] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
83 		     RTE_PTYPE_L4_NONFRAG,
84 	[0x02] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
85 		     RTE_PTYPE_L4_FRAG,
86 	[0x03] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
87 		     RTE_PTYPE_L4_FRAG,
88 	[0x04] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
89 		     RTE_PTYPE_L4_NONFRAG,
90 	[0x06] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
91 		     RTE_PTYPE_L4_FRAG,
92 	[0x08] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
93 		     RTE_PTYPE_L4_NONFRAG,
94 	[0x09] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
95 		     RTE_PTYPE_L4_NONFRAG,
96 	[0x0a] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
97 		     RTE_PTYPE_L4_FRAG,
98 	[0x0b] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
99 		     RTE_PTYPE_L4_FRAG,
100 	/* TCP */
101 	[0x11] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
102 		     RTE_PTYPE_L4_TCP,
103 	[0x14] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
104 		     RTE_PTYPE_L4_TCP,
105 	[0x16] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
106 		     RTE_PTYPE_L4_FRAG,
107 	[0x18] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
108 		     RTE_PTYPE_L4_TCP,
109 	[0x19] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
110 		     RTE_PTYPE_L4_TCP,
111 	/* UDP */
112 	[0x21] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
113 		     RTE_PTYPE_L4_UDP,
114 	[0x24] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
115 		     RTE_PTYPE_L4_UDP,
116 	[0x26] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
117 		     RTE_PTYPE_L4_FRAG,
118 	[0x28] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
119 		     RTE_PTYPE_L4_UDP,
120 	[0x29] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT |
121 		     RTE_PTYPE_L4_UDP,
122 	/* Tunneled - L3 IPV6 */
123 	[0x80] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN,
124 	[0x81] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
125 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
126 		     RTE_PTYPE_INNER_L4_NONFRAG,
127 	[0x82] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
128 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
129 		     RTE_PTYPE_INNER_L4_FRAG,
130 	[0x83] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
131 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
132 		     RTE_PTYPE_INNER_L4_FRAG,
133 	[0x84] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
134 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
135 		     RTE_PTYPE_INNER_L4_NONFRAG,
136 	[0x86] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
137 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
138 		     RTE_PTYPE_INNER_L4_FRAG,
139 	[0x88] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
140 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
141 		     RTE_PTYPE_INNER_L4_NONFRAG,
142 	[0x89] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
143 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
144 		     RTE_PTYPE_INNER_L4_NONFRAG,
145 	[0x8a] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
146 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
147 		     RTE_PTYPE_INNER_L4_FRAG,
148 	[0x8b] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
149 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
150 		     RTE_PTYPE_INNER_L4_FRAG,
151 	/* Tunneled - L3 IPV6, TCP */
152 	[0x91] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
153 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
154 		     RTE_PTYPE_INNER_L4_TCP,
155 	[0x94] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
156 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
157 		     RTE_PTYPE_INNER_L4_TCP,
158 	[0x96] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
159 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
160 		     RTE_PTYPE_INNER_L4_FRAG,
161 	[0x98] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
162 		     RTE_PTYPE_INNER_L3_IPV4_EXT | RTE_PTYPE_INNER_L4_TCP,
163 	[0x99] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
164 		     RTE_PTYPE_INNER_L3_IPV4_EXT | RTE_PTYPE_INNER_L4_TCP,
165 	/* Tunneled - L3 IPV6, UDP */
166 	[0xa1] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
167 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
168 		     RTE_PTYPE_INNER_L4_UDP,
169 	[0xa4] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
170 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
171 		     RTE_PTYPE_INNER_L4_UDP,
172 	[0xa6] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
173 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
174 		     RTE_PTYPE_INNER_L4_FRAG,
175 	[0xa8] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
176 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
177 		     RTE_PTYPE_INNER_L4_UDP,
178 	[0xa9] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN |
179 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
180 		     RTE_PTYPE_INNER_L4_UDP,
181 	/* Tunneled - L3 IPV4 */
182 	[0xc0] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN,
183 	[0xc1] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
184 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
185 		     RTE_PTYPE_INNER_L4_NONFRAG,
186 	[0xc2] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
187 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
188 		     RTE_PTYPE_INNER_L4_FRAG,
189 	[0xc3] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
190 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
191 		     RTE_PTYPE_INNER_L4_FRAG,
192 	[0xc4] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
193 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
194 		     RTE_PTYPE_INNER_L4_NONFRAG,
195 	[0xc6] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
196 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
197 		     RTE_PTYPE_INNER_L4_FRAG,
198 	[0xc8] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
199 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
200 		     RTE_PTYPE_INNER_L4_NONFRAG,
201 	[0xc9] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
202 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
203 		     RTE_PTYPE_INNER_L4_NONFRAG,
204 	[0xca] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
205 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
206 		     RTE_PTYPE_INNER_L4_FRAG,
207 	[0xcb] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
208 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
209 		     RTE_PTYPE_INNER_L4_FRAG,
210 	/* Tunneled - L3 IPV4, TCP */
211 	[0xd1] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
212 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
213 		     RTE_PTYPE_INNER_L4_TCP,
214 	[0xd4] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
215 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
216 		     RTE_PTYPE_INNER_L4_TCP,
217 	[0xd6] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
218 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
219 		     RTE_PTYPE_INNER_L4_FRAG,
220 	[0xd8] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
221 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
222 		     RTE_PTYPE_INNER_L4_TCP,
223 	[0xd9] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
224 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
225 		     RTE_PTYPE_INNER_L4_TCP,
226 	/* Tunneled - L3 IPV4, UDP */
227 	[0xe1] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
228 		     RTE_PTYPE_INNER_L3_IPV4_EXT_UNKNOWN |
229 		     RTE_PTYPE_INNER_L4_UDP,
230 	[0xe4] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
231 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
232 		     RTE_PTYPE_INNER_L4_UDP,
233 	[0xe6] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
234 		     RTE_PTYPE_INNER_L3_IPV6_EXT_UNKNOWN |
235 		     RTE_PTYPE_INNER_L4_FRAG,
236 	[0xe8] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
237 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
238 		     RTE_PTYPE_INNER_L4_UDP,
239 	[0xe9] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN |
240 		     RTE_PTYPE_INNER_L3_IPV4_EXT |
241 		     RTE_PTYPE_INNER_L4_UDP,
242 };
243 
244 /**
245  * Stamp TXBB burst so it won't be reused by the HW.
246  *
247  * Routine is used when freeing WQE used by the chip or when failing
248  * building an WQ entry has failed leaving partial information on the queue.
249  *
250  * @param sq
251  *   Pointer to the SQ structure.
252  * @param start
253  *   Pointer to the first TXBB to stamp.
254  * @param end
255  *   Pointer to the followed end TXBB to stamp.
256  *
257  * @return
258  *   Stamping burst size in byte units.
259  */
260 static uint32_t
261 mlx4_txq_stamp_freed_wqe(struct mlx4_sq *sq, volatile uint32_t *start,
262 			 volatile uint32_t *end)
263 {
264 	uint32_t stamp = sq->stamp;
265 	int32_t size = (intptr_t)end - (intptr_t)start;
266 
267 	assert(start != end);
268 	/* Hold SQ ring wrap around. */
269 	if (size < 0) {
270 		size = (int32_t)sq->size + size;
271 		do {
272 			*start = stamp;
273 			start += MLX4_SQ_STAMP_DWORDS;
274 		} while (start != (volatile uint32_t *)sq->eob);
275 		start = (volatile uint32_t *)sq->buf;
276 		/* Flip invalid stamping ownership. */
277 		stamp ^= RTE_BE32(1u << MLX4_SQ_OWNER_BIT);
278 		sq->stamp = stamp;
279 		if (start == end)
280 			return size;
281 	}
282 	do {
283 		*start = stamp;
284 		start += MLX4_SQ_STAMP_DWORDS;
285 	} while (start != end);
286 	return (uint32_t)size;
287 }
288 
289 /**
290  * Manage Tx completions.
291  *
292  * When sending a burst, mlx4_tx_burst() posts several WRs.
293  * To improve performance, a completion event is only required once every
294  * MLX4_PMD_TX_PER_COMP_REQ sends. Doing so discards completion information
295  * for other WRs, but this information would not be used anyway.
296  *
297  * @param txq
298  *   Pointer to Tx queue structure.
299  * @param elts_m
300  *   Tx elements number mask.
301  * @param sq
302  *   Pointer to the SQ structure.
303  */
304 static void
305 mlx4_txq_complete(struct txq *txq, const unsigned int elts_m,
306 		  struct mlx4_sq *sq)
307 {
308 	unsigned int elts_tail = txq->elts_tail;
309 	struct mlx4_cq *cq = &txq->mcq;
310 	volatile struct mlx4_cqe *cqe;
311 	uint32_t completed;
312 	uint32_t cons_index = cq->cons_index;
313 	volatile uint32_t *first_txbb;
314 
315 	/*
316 	 * Traverse over all CQ entries reported and handle each WQ entry
317 	 * reported by them.
318 	 */
319 	do {
320 		cqe = (volatile struct mlx4_cqe *)mlx4_get_cqe(cq, cons_index);
321 		if (unlikely(!!(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK) ^
322 		    !!(cons_index & cq->cqe_cnt)))
323 			break;
324 #ifndef NDEBUG
325 		/*
326 		 * Make sure we read the CQE after we read the ownership bit.
327 		 */
328 		rte_io_rmb();
329 		if (unlikely((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) ==
330 			     MLX4_CQE_OPCODE_ERROR)) {
331 			volatile struct mlx4_err_cqe *cqe_err =
332 				(volatile struct mlx4_err_cqe *)cqe;
333 			ERROR("%p CQE error - vendor syndrome: 0x%x"
334 			      " syndrome: 0x%x\n",
335 			      (void *)txq, cqe_err->vendor_err,
336 			      cqe_err->syndrome);
337 			break;
338 		}
339 #endif /* NDEBUG */
340 		cons_index++;
341 	} while (1);
342 	completed = (cons_index - cq->cons_index) * txq->elts_comp_cd_init;
343 	if (unlikely(!completed))
344 		return;
345 	/* First stamping address is the end of the last one. */
346 	first_txbb = (&(*txq->elts)[elts_tail & elts_m])->eocb;
347 	elts_tail += completed;
348 	/* The new tail element holds the end address. */
349 	sq->remain_size += mlx4_txq_stamp_freed_wqe(sq, first_txbb,
350 		(&(*txq->elts)[elts_tail & elts_m])->eocb);
351 	/* Update CQ consumer index. */
352 	cq->cons_index = cons_index;
353 	*cq->set_ci_db = rte_cpu_to_be_32(cons_index & MLX4_CQ_DB_CI_MASK);
354 	txq->elts_tail = elts_tail;
355 }
356 
357 /**
358  * Write Tx data segment to the SQ.
359  *
360  * @param dseg
361  *   Pointer to data segment in SQ.
362  * @param lkey
363  *   Memory region lkey.
364  * @param addr
365  *   Data address.
366  * @param byte_count
367  *   Big endian bytes count of the data to send.
368  */
369 static inline void
370 mlx4_fill_tx_data_seg(volatile struct mlx4_wqe_data_seg *dseg,
371 		       uint32_t lkey, uintptr_t addr, rte_be32_t  byte_count)
372 {
373 	dseg->addr = rte_cpu_to_be_64(addr);
374 	dseg->lkey = lkey;
375 #if RTE_CACHE_LINE_SIZE < 64
376 	/*
377 	 * Need a barrier here before writing the byte_count
378 	 * fields to make sure that all the data is visible
379 	 * before the byte_count field is set.
380 	 * Otherwise, if the segment begins a new cacheline,
381 	 * the HCA prefetcher could grab the 64-byte chunk and
382 	 * get a valid (!= 0xffffffff) byte count but stale
383 	 * data, and end up sending the wrong data.
384 	 */
385 	rte_io_wmb();
386 #endif /* RTE_CACHE_LINE_SIZE */
387 	dseg->byte_count = byte_count;
388 }
389 
390 /**
391  * Obtain and calculate TSO information needed for assembling a TSO WQE.
392  *
393  * @param buf
394  *   Pointer to the first packet mbuf.
395  * @param txq
396  *   Pointer to Tx queue structure.
397  * @param tinfo
398  *   Pointer to a structure to fill the info with.
399  *
400  * @return
401  *   0 on success, negative value upon error.
402  */
403 static inline int
404 mlx4_tx_burst_tso_get_params(struct rte_mbuf *buf,
405 			     struct txq *txq,
406 			     struct tso_info *tinfo)
407 {
408 	struct mlx4_sq *sq = &txq->msq;
409 	const uint8_t tunneled = txq->priv->hw_csum_l2tun &&
410 				 (buf->ol_flags & PKT_TX_TUNNEL_MASK);
411 
412 	tinfo->tso_header_size = buf->l2_len + buf->l3_len + buf->l4_len;
413 	if (tunneled)
414 		tinfo->tso_header_size +=
415 				buf->outer_l2_len + buf->outer_l3_len;
416 	if (unlikely(buf->tso_segsz == 0 ||
417 		     tinfo->tso_header_size == 0 ||
418 		     tinfo->tso_header_size > MLX4_MAX_TSO_HEADER ||
419 		     tinfo->tso_header_size > buf->data_len))
420 		return -EINVAL;
421 	/*
422 	 * Calculate the WQE TSO segment size
423 	 * Note:
424 	 * 1. An LSO segment must be padded such that the subsequent data
425 	 *    segment is 16-byte aligned.
426 	 * 2. The start address of the TSO segment is always 16 Bytes aligned.
427 	 */
428 	tinfo->wqe_tso_seg_size = RTE_ALIGN(sizeof(struct mlx4_wqe_lso_seg) +
429 					    tinfo->tso_header_size,
430 					    sizeof(struct mlx4_wqe_data_seg));
431 	tinfo->fence_size = ((sizeof(struct mlx4_wqe_ctrl_seg) +
432 			     tinfo->wqe_tso_seg_size) >> MLX4_SEG_SHIFT) +
433 			     buf->nb_segs;
434 	tinfo->wqe_size =
435 		RTE_ALIGN((uint32_t)(tinfo->fence_size << MLX4_SEG_SHIFT),
436 			  MLX4_TXBB_SIZE);
437 	/* Validate WQE size and WQE space in the send queue. */
438 	if (sq->remain_size < tinfo->wqe_size ||
439 	    tinfo->wqe_size > MLX4_MAX_WQE_SIZE)
440 		return -ENOMEM;
441 	/* Init pv. */
442 	tinfo->pv = (struct pv *)txq->bounce_buf;
443 	tinfo->pv_counter = 0;
444 	return 0;
445 }
446 
447 /**
448  * Fill the TSO WQE data segments with info on buffers to transmit .
449  *
450  * @param buf
451  *   Pointer to the first packet mbuf.
452  * @param txq
453  *   Pointer to Tx queue structure.
454  * @param tinfo
455  *   Pointer to TSO info to use.
456  * @param dseg
457  *   Pointer to the first data segment in the TSO WQE.
458  * @param ctrl
459  *   Pointer to the control segment in the TSO WQE.
460  *
461  * @return
462  *   0 on success, negative value upon error.
463  */
464 static inline volatile struct mlx4_wqe_ctrl_seg *
465 mlx4_tx_burst_fill_tso_dsegs(struct rte_mbuf *buf,
466 			     struct txq *txq,
467 			     struct tso_info *tinfo,
468 			     volatile struct mlx4_wqe_data_seg *dseg,
469 			     volatile struct mlx4_wqe_ctrl_seg *ctrl)
470 {
471 	uint32_t lkey;
472 	int nb_segs = buf->nb_segs;
473 	int nb_segs_txbb;
474 	struct mlx4_sq *sq = &txq->msq;
475 	struct rte_mbuf *sbuf = buf;
476 	struct pv *pv = tinfo->pv;
477 	int *pv_counter = &tinfo->pv_counter;
478 	volatile struct mlx4_wqe_ctrl_seg *ctrl_next =
479 			(volatile struct mlx4_wqe_ctrl_seg *)
480 				((volatile uint8_t *)ctrl + tinfo->wqe_size);
481 	uint16_t data_len = sbuf->data_len - tinfo->tso_header_size;
482 	uintptr_t data_addr = rte_pktmbuf_mtod_offset(sbuf, uintptr_t,
483 						      tinfo->tso_header_size);
484 
485 	do {
486 		/* how many dseg entries do we have in the current TXBB ? */
487 		nb_segs_txbb = (MLX4_TXBB_SIZE -
488 				((uintptr_t)dseg & (MLX4_TXBB_SIZE - 1))) >>
489 			       MLX4_SEG_SHIFT;
490 		switch (nb_segs_txbb) {
491 #ifndef NDEBUG
492 		default:
493 			/* Should never happen. */
494 			rte_panic("%p: Invalid number of SGEs(%d) for a TXBB",
495 			(void *)txq, nb_segs_txbb);
496 			/* rte_panic never returns. */
497 			break;
498 #endif /* NDEBUG */
499 		case 4:
500 			/* Memory region key for this memory pool. */
501 			lkey = mlx4_tx_mb2mr(txq, sbuf);
502 			if (unlikely(lkey == (uint32_t)-1))
503 				goto err;
504 			dseg->addr = rte_cpu_to_be_64(data_addr);
505 			dseg->lkey = lkey;
506 			/*
507 			 * This data segment starts at the beginning of a new
508 			 * TXBB, so we need to postpone its byte_count writing
509 			 * for later.
510 			 */
511 			pv[*pv_counter].dseg = dseg;
512 			/*
513 			 * Zero length segment is treated as inline segment
514 			 * with zero data.
515 			 */
516 			pv[(*pv_counter)++].val =
517 				rte_cpu_to_be_32(data_len ?
518 						 data_len :
519 						 0x80000000);
520 			if (--nb_segs == 0)
521 				return ctrl_next;
522 			/* Prepare next buf info */
523 			sbuf = sbuf->next;
524 			dseg++;
525 			data_len = sbuf->data_len;
526 			data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
527 			/* fallthrough */
528 		case 3:
529 			lkey = mlx4_tx_mb2mr(txq, sbuf);
530 			if (unlikely(lkey == (uint32_t)-1))
531 				goto err;
532 			mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
533 					rte_cpu_to_be_32(data_len ?
534 							 data_len :
535 							 0x80000000));
536 			if (--nb_segs == 0)
537 				return ctrl_next;
538 			/* Prepare next buf info */
539 			sbuf = sbuf->next;
540 			dseg++;
541 			data_len = sbuf->data_len;
542 			data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
543 			/* fallthrough */
544 		case 2:
545 			lkey = mlx4_tx_mb2mr(txq, sbuf);
546 			if (unlikely(lkey == (uint32_t)-1))
547 				goto err;
548 			mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
549 					rte_cpu_to_be_32(data_len ?
550 							 data_len :
551 							 0x80000000));
552 			if (--nb_segs == 0)
553 				return ctrl_next;
554 			/* Prepare next buf info */
555 			sbuf = sbuf->next;
556 			dseg++;
557 			data_len = sbuf->data_len;
558 			data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
559 			/* fallthrough */
560 		case 1:
561 			lkey = mlx4_tx_mb2mr(txq, sbuf);
562 			if (unlikely(lkey == (uint32_t)-1))
563 				goto err;
564 			mlx4_fill_tx_data_seg(dseg, lkey, data_addr,
565 					rte_cpu_to_be_32(data_len ?
566 							 data_len :
567 							 0x80000000));
568 			if (--nb_segs == 0)
569 				return ctrl_next;
570 			/* Prepare next buf info */
571 			sbuf = sbuf->next;
572 			dseg++;
573 			data_len = sbuf->data_len;
574 			data_addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
575 			/* fallthrough */
576 		}
577 		/* Wrap dseg if it points at the end of the queue. */
578 		if ((volatile uint8_t *)dseg >= sq->eob)
579 			dseg = (volatile struct mlx4_wqe_data_seg *)
580 					((volatile uint8_t *)dseg - sq->size);
581 	} while (true);
582 err:
583 	return NULL;
584 }
585 
586 /**
587  * Fill the packet's l2, l3 and l4 headers to the WQE.
588  *
589  * This will be used as the header for each TSO segment that is transmitted.
590  *
591  * @param buf
592  *   Pointer to the first packet mbuf.
593  * @param txq
594  *   Pointer to Tx queue structure.
595  * @param tinfo
596  *   Pointer to TSO info to use.
597  * @param ctrl
598  *   Pointer to the control segment in the TSO WQE.
599  *
600  * @return
601  *   0 on success, negative value upon error.
602  */
603 static inline volatile struct mlx4_wqe_data_seg *
604 mlx4_tx_burst_fill_tso_hdr(struct rte_mbuf *buf,
605 			   struct txq *txq,
606 			   struct tso_info *tinfo,
607 			   volatile struct mlx4_wqe_ctrl_seg *ctrl)
608 {
609 	volatile struct mlx4_wqe_lso_seg *tseg =
610 		(volatile struct mlx4_wqe_lso_seg *)(ctrl + 1);
611 	struct mlx4_sq *sq = &txq->msq;
612 	struct pv *pv = tinfo->pv;
613 	int *pv_counter = &tinfo->pv_counter;
614 	int remain_size = tinfo->tso_header_size;
615 	char *from = rte_pktmbuf_mtod(buf, char *);
616 	uint16_t txbb_avail_space;
617 	/* Union to overcome volatile constraints when copying TSO header. */
618 	union {
619 		volatile uint8_t *vto;
620 		uint8_t *to;
621 	} thdr = { .vto = (volatile uint8_t *)tseg->header, };
622 
623 	/*
624 	 * TSO data always starts at offset 20 from the beginning of the TXBB
625 	 * (16 byte ctrl + 4byte TSO desc). Since each TXBB is 64Byte aligned
626 	 * we can write the first 44 TSO header bytes without worry for TxQ
627 	 * wrapping or overwriting the first TXBB 32bit word.
628 	 */
629 	txbb_avail_space = MLX4_TXBB_SIZE -
630 			   (sizeof(struct mlx4_wqe_ctrl_seg) +
631 			    sizeof(struct mlx4_wqe_lso_seg));
632 	while (remain_size >= (int)(txbb_avail_space + sizeof(uint32_t))) {
633 		/* Copy to end of txbb. */
634 		rte_memcpy(thdr.to, from, txbb_avail_space);
635 		from += txbb_avail_space;
636 		thdr.to += txbb_avail_space;
637 		/* New TXBB, Check for TxQ wrap. */
638 		if (thdr.to >= sq->eob)
639 			thdr.vto = sq->buf;
640 		/* New TXBB, stash the first 32bits for later use. */
641 		pv[*pv_counter].dst = (volatile uint32_t *)thdr.to;
642 		pv[(*pv_counter)++].val = *(uint32_t *)from,
643 		from += sizeof(uint32_t);
644 		thdr.to += sizeof(uint32_t);
645 		remain_size -= txbb_avail_space + sizeof(uint32_t);
646 		/* Avail space in new TXBB is TXBB size - 4 */
647 		txbb_avail_space = MLX4_TXBB_SIZE - sizeof(uint32_t);
648 	}
649 	if (remain_size > txbb_avail_space) {
650 		rte_memcpy(thdr.to, from, txbb_avail_space);
651 		from += txbb_avail_space;
652 		thdr.to += txbb_avail_space;
653 		remain_size -= txbb_avail_space;
654 		/* New TXBB, Check for TxQ wrap. */
655 		if (thdr.to >= sq->eob)
656 			thdr.vto = sq->buf;
657 		pv[*pv_counter].dst = (volatile uint32_t *)thdr.to;
658 		rte_memcpy(&pv[*pv_counter].val, from, remain_size);
659 		(*pv_counter)++;
660 	} else if (remain_size) {
661 		rte_memcpy(thdr.to, from, remain_size);
662 	}
663 	tseg->mss_hdr_size = rte_cpu_to_be_32((buf->tso_segsz << 16) |
664 					      tinfo->tso_header_size);
665 	/* Calculate data segment location */
666 	return (volatile struct mlx4_wqe_data_seg *)
667 				((uintptr_t)tseg + tinfo->wqe_tso_seg_size);
668 }
669 
670 /**
671  * Write data segments and header for TSO uni/multi segment packet.
672  *
673  * @param buf
674  *   Pointer to the first packet mbuf.
675  * @param txq
676  *   Pointer to Tx queue structure.
677  * @param ctrl
678  *   Pointer to the WQE control segment.
679  *
680  * @return
681  *   Pointer to the next WQE control segment on success, NULL otherwise.
682  */
683 static volatile struct mlx4_wqe_ctrl_seg *
684 mlx4_tx_burst_tso(struct rte_mbuf *buf, struct txq *txq,
685 		  volatile struct mlx4_wqe_ctrl_seg *ctrl)
686 {
687 	volatile struct mlx4_wqe_data_seg *dseg;
688 	volatile struct mlx4_wqe_ctrl_seg *ctrl_next;
689 	struct mlx4_sq *sq = &txq->msq;
690 	struct tso_info tinfo;
691 	struct pv *pv;
692 	int pv_counter;
693 	int ret;
694 
695 	ret = mlx4_tx_burst_tso_get_params(buf, txq, &tinfo);
696 	if (unlikely(ret))
697 		goto error;
698 	dseg = mlx4_tx_burst_fill_tso_hdr(buf, txq, &tinfo, ctrl);
699 	if (unlikely(dseg == NULL))
700 		goto error;
701 	if ((uintptr_t)dseg >= (uintptr_t)sq->eob)
702 		dseg = (volatile struct mlx4_wqe_data_seg *)
703 					((uintptr_t)dseg - sq->size);
704 	ctrl_next = mlx4_tx_burst_fill_tso_dsegs(buf, txq, &tinfo, dseg, ctrl);
705 	if (unlikely(ctrl_next == NULL))
706 		goto error;
707 	/* Write the first DWORD of each TXBB save earlier. */
708 	if (likely(tinfo.pv_counter)) {
709 		pv = tinfo.pv;
710 		pv_counter = tinfo.pv_counter;
711 		/* Need a barrier here before writing the first TXBB word. */
712 		rte_io_wmb();
713 		do {
714 			--pv_counter;
715 			*pv[pv_counter].dst = pv[pv_counter].val;
716 		} while (pv_counter > 0);
717 	}
718 	ctrl->fence_size = tinfo.fence_size;
719 	sq->remain_size -= tinfo.wqe_size;
720 	return ctrl_next;
721 error:
722 	txq->stats.odropped++;
723 	return NULL;
724 }
725 
726 /**
727  * Write data segments of multi-segment packet.
728  *
729  * @param buf
730  *   Pointer to the first packet mbuf.
731  * @param txq
732  *   Pointer to Tx queue structure.
733  * @param ctrl
734  *   Pointer to the WQE control segment.
735  *
736  * @return
737  *   Pointer to the next WQE control segment on success, NULL otherwise.
738  */
739 static volatile struct mlx4_wqe_ctrl_seg *
740 mlx4_tx_burst_segs(struct rte_mbuf *buf, struct txq *txq,
741 		   volatile struct mlx4_wqe_ctrl_seg *ctrl)
742 {
743 	struct pv *pv = (struct pv *)txq->bounce_buf;
744 	struct mlx4_sq *sq = &txq->msq;
745 	struct rte_mbuf *sbuf = buf;
746 	uint32_t lkey;
747 	int pv_counter = 0;
748 	int nb_segs = buf->nb_segs;
749 	uint32_t wqe_size;
750 	volatile struct mlx4_wqe_data_seg *dseg =
751 		(volatile struct mlx4_wqe_data_seg *)(ctrl + 1);
752 
753 	ctrl->fence_size = 1 + nb_segs;
754 	wqe_size = RTE_ALIGN((uint32_t)(ctrl->fence_size << MLX4_SEG_SHIFT),
755 			     MLX4_TXBB_SIZE);
756 	/* Validate WQE size and WQE space in the send queue. */
757 	if (sq->remain_size < wqe_size ||
758 	    wqe_size > MLX4_MAX_WQE_SIZE)
759 		return NULL;
760 	/*
761 	 * Fill the data segments with buffer information.
762 	 * First WQE TXBB head segment is always control segment,
763 	 * so jump to tail TXBB data segments code for the first
764 	 * WQE data segments filling.
765 	 */
766 	goto txbb_tail_segs;
767 txbb_head_seg:
768 	/* Memory region key (big endian) for this memory pool. */
769 	lkey = mlx4_tx_mb2mr(txq, sbuf);
770 	if (unlikely(lkey == (uint32_t)-1)) {
771 		DEBUG("%p: unable to get MP <-> MR association",
772 		      (void *)txq);
773 		return NULL;
774 	}
775 	/* Handle WQE wraparound. */
776 	if (dseg >=
777 		(volatile struct mlx4_wqe_data_seg *)sq->eob)
778 		dseg = (volatile struct mlx4_wqe_data_seg *)
779 			sq->buf;
780 	dseg->addr = rte_cpu_to_be_64(rte_pktmbuf_mtod(sbuf, uintptr_t));
781 	dseg->lkey = lkey;
782 	/*
783 	 * This data segment starts at the beginning of a new
784 	 * TXBB, so we need to postpone its byte_count writing
785 	 * for later.
786 	 */
787 	pv[pv_counter].dseg = dseg;
788 	/*
789 	 * Zero length segment is treated as inline segment
790 	 * with zero data.
791 	 */
792 	pv[pv_counter++].val = rte_cpu_to_be_32(sbuf->data_len ?
793 						sbuf->data_len : 0x80000000);
794 	sbuf = sbuf->next;
795 	dseg++;
796 	nb_segs--;
797 txbb_tail_segs:
798 	/* Jump to default if there are more than two segments remaining. */
799 	switch (nb_segs) {
800 	default:
801 		lkey = mlx4_tx_mb2mr(txq, sbuf);
802 		if (unlikely(lkey == (uint32_t)-1)) {
803 			DEBUG("%p: unable to get MP <-> MR association",
804 			      (void *)txq);
805 			return NULL;
806 		}
807 		mlx4_fill_tx_data_seg(dseg, lkey,
808 				      rte_pktmbuf_mtod(sbuf, uintptr_t),
809 				      rte_cpu_to_be_32(sbuf->data_len ?
810 						       sbuf->data_len :
811 						       0x80000000));
812 		sbuf = sbuf->next;
813 		dseg++;
814 		nb_segs--;
815 		/* fallthrough */
816 	case 2:
817 		lkey = mlx4_tx_mb2mr(txq, sbuf);
818 		if (unlikely(lkey == (uint32_t)-1)) {
819 			DEBUG("%p: unable to get MP <-> MR association",
820 			      (void *)txq);
821 			return NULL;
822 		}
823 		mlx4_fill_tx_data_seg(dseg, lkey,
824 				      rte_pktmbuf_mtod(sbuf, uintptr_t),
825 				      rte_cpu_to_be_32(sbuf->data_len ?
826 						       sbuf->data_len :
827 						       0x80000000));
828 		sbuf = sbuf->next;
829 		dseg++;
830 		nb_segs--;
831 		/* fallthrough */
832 	case 1:
833 		lkey = mlx4_tx_mb2mr(txq, sbuf);
834 		if (unlikely(lkey == (uint32_t)-1)) {
835 			DEBUG("%p: unable to get MP <-> MR association",
836 			      (void *)txq);
837 			return NULL;
838 		}
839 		mlx4_fill_tx_data_seg(dseg, lkey,
840 				      rte_pktmbuf_mtod(sbuf, uintptr_t),
841 				      rte_cpu_to_be_32(sbuf->data_len ?
842 						       sbuf->data_len :
843 						       0x80000000));
844 		nb_segs--;
845 		if (nb_segs) {
846 			sbuf = sbuf->next;
847 			dseg++;
848 			goto txbb_head_seg;
849 		}
850 		/* fallthrough */
851 	case 0:
852 		break;
853 	}
854 	/* Write the first DWORD of each TXBB save earlier. */
855 	if (pv_counter) {
856 		/* Need a barrier here before writing the byte_count. */
857 		rte_io_wmb();
858 		for (--pv_counter; pv_counter  >= 0; pv_counter--)
859 			pv[pv_counter].dseg->byte_count = pv[pv_counter].val;
860 	}
861 	sq->remain_size -= wqe_size;
862 	/* Align next WQE address to the next TXBB. */
863 	return (volatile struct mlx4_wqe_ctrl_seg *)
864 		((volatile uint8_t *)ctrl + wqe_size);
865 }
866 
867 /**
868  * DPDK callback for Tx.
869  *
870  * @param dpdk_txq
871  *   Generic pointer to Tx queue structure.
872  * @param[in] pkts
873  *   Packets to transmit.
874  * @param pkts_n
875  *   Number of packets in array.
876  *
877  * @return
878  *   Number of packets successfully transmitted (<= pkts_n).
879  */
880 uint16_t
881 mlx4_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
882 {
883 	struct txq *txq = (struct txq *)dpdk_txq;
884 	unsigned int elts_head = txq->elts_head;
885 	const unsigned int elts_n = txq->elts_n;
886 	const unsigned int elts_m = elts_n - 1;
887 	unsigned int bytes_sent = 0;
888 	unsigned int i;
889 	unsigned int max = elts_head - txq->elts_tail;
890 	struct mlx4_sq *sq = &txq->msq;
891 	volatile struct mlx4_wqe_ctrl_seg *ctrl;
892 	struct txq_elt *elt;
893 
894 	assert(txq->elts_comp_cd != 0);
895 	if (likely(max >= txq->elts_comp_cd_init))
896 		mlx4_txq_complete(txq, elts_m, sq);
897 	max = elts_n - max;
898 	assert(max >= 1);
899 	assert(max <= elts_n);
900 	/* Always leave one free entry in the ring. */
901 	--max;
902 	if (max > pkts_n)
903 		max = pkts_n;
904 	elt = &(*txq->elts)[elts_head & elts_m];
905 	/* First Tx burst element saves the next WQE control segment. */
906 	ctrl = elt->wqe;
907 	for (i = 0; (i != max); ++i) {
908 		struct rte_mbuf *buf = pkts[i];
909 		struct txq_elt *elt_next = &(*txq->elts)[++elts_head & elts_m];
910 		uint32_t owner_opcode = sq->owner_opcode;
911 		volatile struct mlx4_wqe_data_seg *dseg =
912 				(volatile struct mlx4_wqe_data_seg *)(ctrl + 1);
913 		volatile struct mlx4_wqe_ctrl_seg *ctrl_next;
914 		union {
915 			uint32_t flags;
916 			uint16_t flags16[2];
917 		} srcrb;
918 		uint32_t lkey;
919 		bool tso = txq->priv->tso && (buf->ol_flags & PKT_TX_TCP_SEG);
920 
921 		/* Clean up old buffer. */
922 		if (likely(elt->buf != NULL)) {
923 			struct rte_mbuf *tmp = elt->buf;
924 
925 #ifndef NDEBUG
926 			/* Poisoning. */
927 			memset(&elt->buf, 0x66, sizeof(struct rte_mbuf *));
928 #endif
929 			/* Faster than rte_pktmbuf_free(). */
930 			do {
931 				struct rte_mbuf *next = tmp->next;
932 
933 				rte_pktmbuf_free_seg(tmp);
934 				tmp = next;
935 			} while (tmp != NULL);
936 		}
937 		RTE_MBUF_PREFETCH_TO_FREE(elt_next->buf);
938 		if (tso) {
939 			/* Change opcode to TSO */
940 			owner_opcode &= ~MLX4_OPCODE_CONFIG_CMD;
941 			owner_opcode |= MLX4_OPCODE_LSO | MLX4_WQE_CTRL_RR;
942 			ctrl_next = mlx4_tx_burst_tso(buf, txq, ctrl);
943 			if (!ctrl_next) {
944 				elt->buf = NULL;
945 				break;
946 			}
947 		} else if (buf->nb_segs == 1) {
948 			/* Validate WQE space in the send queue. */
949 			if (sq->remain_size < MLX4_TXBB_SIZE) {
950 				elt->buf = NULL;
951 				break;
952 			}
953 			lkey = mlx4_tx_mb2mr(txq, buf);
954 			if (unlikely(lkey == (uint32_t)-1)) {
955 				/* MR does not exist. */
956 				DEBUG("%p: unable to get MP <-> MR association",
957 				      (void *)txq);
958 				elt->buf = NULL;
959 				break;
960 			}
961 			mlx4_fill_tx_data_seg(dseg++, lkey,
962 					      rte_pktmbuf_mtod(buf, uintptr_t),
963 					      rte_cpu_to_be_32(buf->data_len));
964 			/* Set WQE size in 16-byte units. */
965 			ctrl->fence_size = 0x2;
966 			sq->remain_size -= MLX4_TXBB_SIZE;
967 			/* Align next WQE address to the next TXBB. */
968 			ctrl_next = ctrl + 0x4;
969 		} else {
970 			ctrl_next = mlx4_tx_burst_segs(buf, txq, ctrl);
971 			if (!ctrl_next) {
972 				elt->buf = NULL;
973 				break;
974 			}
975 		}
976 		/* Hold SQ ring wrap around. */
977 		if ((volatile uint8_t *)ctrl_next >= sq->eob) {
978 			ctrl_next = (volatile struct mlx4_wqe_ctrl_seg *)
979 				((volatile uint8_t *)ctrl_next - sq->size);
980 			/* Flip HW valid ownership. */
981 			sq->owner_opcode ^= 1u << MLX4_SQ_OWNER_BIT;
982 		}
983 		/*
984 		 * For raw Ethernet, the SOLICIT flag is used to indicate
985 		 * that no ICRC should be calculated.
986 		 */
987 		if (--txq->elts_comp_cd == 0) {
988 			/* Save the completion burst end address. */
989 			elt_next->eocb = (volatile uint32_t *)ctrl_next;
990 			txq->elts_comp_cd = txq->elts_comp_cd_init;
991 			srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT |
992 					       MLX4_WQE_CTRL_CQ_UPDATE);
993 		} else {
994 			srcrb.flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT);
995 		}
996 		/* Enable HW checksum offload if requested */
997 		if (txq->csum &&
998 		    (buf->ol_flags &
999 		     (PKT_TX_IP_CKSUM | PKT_TX_TCP_CKSUM | PKT_TX_UDP_CKSUM))) {
1000 			const uint64_t is_tunneled = (buf->ol_flags &
1001 						      (PKT_TX_TUNNEL_GRE |
1002 						       PKT_TX_TUNNEL_VXLAN));
1003 
1004 			if (is_tunneled && txq->csum_l2tun) {
1005 				owner_opcode |= MLX4_WQE_CTRL_IIP_HDR_CSUM |
1006 						MLX4_WQE_CTRL_IL4_HDR_CSUM;
1007 				if (buf->ol_flags & PKT_TX_OUTER_IP_CKSUM)
1008 					srcrb.flags |=
1009 					    RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM);
1010 			} else {
1011 				srcrb.flags |=
1012 					RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM |
1013 						MLX4_WQE_CTRL_TCP_UDP_CSUM);
1014 			}
1015 		}
1016 		if (txq->lb) {
1017 			/*
1018 			 * Copy destination MAC address to the WQE, this allows
1019 			 * loopback in eSwitch, so that VFs and PF can
1020 			 * communicate with each other.
1021 			 */
1022 			srcrb.flags16[0] = *(rte_pktmbuf_mtod(buf, uint16_t *));
1023 			ctrl->imm = *(rte_pktmbuf_mtod_offset(buf, uint32_t *,
1024 					      sizeof(uint16_t)));
1025 		} else {
1026 			ctrl->imm = 0;
1027 		}
1028 		ctrl->srcrb_flags = srcrb.flags;
1029 		/*
1030 		 * Make sure descriptor is fully written before
1031 		 * setting ownership bit (because HW can start
1032 		 * executing as soon as we do).
1033 		 */
1034 		rte_io_wmb();
1035 		ctrl->owner_opcode = rte_cpu_to_be_32(owner_opcode);
1036 		elt->buf = buf;
1037 		bytes_sent += buf->pkt_len;
1038 		ctrl = ctrl_next;
1039 		elt = elt_next;
1040 	}
1041 	/* Take a shortcut if nothing must be sent. */
1042 	if (unlikely(i == 0))
1043 		return 0;
1044 	/* Save WQE address of the next Tx burst element. */
1045 	elt->wqe = ctrl;
1046 	/* Increment send statistics counters. */
1047 	txq->stats.opackets += i;
1048 	txq->stats.obytes += bytes_sent;
1049 	/* Make sure that descriptors are written before doorbell record. */
1050 	rte_wmb();
1051 	/* Ring QP doorbell. */
1052 	rte_write32(txq->msq.doorbell_qpn, MLX4_TX_BFREG(txq));
1053 	txq->elts_head += i;
1054 	return i;
1055 }
1056 
1057 /**
1058  * Translate Rx completion flags to packet type.
1059  *
1060  * @param[in] cqe
1061  *   Pointer to CQE.
1062  *
1063  * @return
1064  *   Packet type for struct rte_mbuf.
1065  */
1066 static inline uint32_t
1067 rxq_cq_to_pkt_type(volatile struct mlx4_cqe *cqe,
1068 		   uint32_t l2tun_offload)
1069 {
1070 	uint8_t idx = 0;
1071 	uint32_t pinfo = rte_be_to_cpu_32(cqe->vlan_my_qpn);
1072 	uint32_t status = rte_be_to_cpu_32(cqe->status);
1073 
1074 	/*
1075 	 * The index to the array should have:
1076 	 *  bit[7] - MLX4_CQE_L2_TUNNEL
1077 	 *  bit[6] - MLX4_CQE_L2_TUNNEL_IPV4
1078 	 */
1079 	if (l2tun_offload && (pinfo & MLX4_CQE_L2_TUNNEL))
1080 		idx |= ((pinfo & MLX4_CQE_L2_TUNNEL) >> 20) |
1081 		       ((pinfo & MLX4_CQE_L2_TUNNEL_IPV4) >> 19);
1082 	/*
1083 	 * The index to the array should have:
1084 	 *  bit[5] - MLX4_CQE_STATUS_UDP
1085 	 *  bit[4] - MLX4_CQE_STATUS_TCP
1086 	 *  bit[3] - MLX4_CQE_STATUS_IPV4OPT
1087 	 *  bit[2] - MLX4_CQE_STATUS_IPV6
1088 	 *  bit[1] - MLX4_CQE_STATUS_IPF
1089 	 *  bit[0] - MLX4_CQE_STATUS_IPV4
1090 	 * giving a total of up to 256 entries.
1091 	 */
1092 	idx |= ((status & MLX4_CQE_STATUS_PTYPE_MASK) >> 22);
1093 	if (status & MLX4_CQE_STATUS_IPV6)
1094 		idx |= ((status & MLX4_CQE_STATUS_IPV6F) >> 11);
1095 	return mlx4_ptype_table[idx];
1096 }
1097 
1098 /**
1099  * Translate Rx completion flags to offload flags.
1100  *
1101  * @param flags
1102  *   Rx completion flags returned by mlx4_cqe_flags().
1103  * @param csum
1104  *   Whether Rx checksums are enabled.
1105  * @param csum_l2tun
1106  *   Whether Rx L2 tunnel checksums are enabled.
1107  *
1108  * @return
1109  *   Offload flags (ol_flags) in mbuf format.
1110  */
1111 static inline uint32_t
1112 rxq_cq_to_ol_flags(uint32_t flags, int csum, int csum_l2tun)
1113 {
1114 	uint32_t ol_flags = 0;
1115 
1116 	if (csum)
1117 		ol_flags |=
1118 			mlx4_transpose(flags,
1119 				       MLX4_CQE_STATUS_IP_HDR_CSUM_OK,
1120 				       PKT_RX_IP_CKSUM_GOOD) |
1121 			mlx4_transpose(flags,
1122 				       MLX4_CQE_STATUS_TCP_UDP_CSUM_OK,
1123 				       PKT_RX_L4_CKSUM_GOOD);
1124 	if ((flags & MLX4_CQE_L2_TUNNEL) && csum_l2tun)
1125 		ol_flags |=
1126 			mlx4_transpose(flags,
1127 				       MLX4_CQE_L2_TUNNEL_IPOK,
1128 				       PKT_RX_IP_CKSUM_GOOD) |
1129 			mlx4_transpose(flags,
1130 				       MLX4_CQE_L2_TUNNEL_L4_CSUM,
1131 				       PKT_RX_L4_CKSUM_GOOD);
1132 	return ol_flags;
1133 }
1134 
1135 /**
1136  * Extract checksum information from CQE flags.
1137  *
1138  * @param cqe
1139  *   Pointer to CQE structure.
1140  * @param csum
1141  *   Whether Rx checksums are enabled.
1142  * @param csum_l2tun
1143  *   Whether Rx L2 tunnel checksums are enabled.
1144  *
1145  * @return
1146  *   CQE checksum information.
1147  */
1148 static inline uint32_t
1149 mlx4_cqe_flags(volatile struct mlx4_cqe *cqe, int csum, int csum_l2tun)
1150 {
1151 	uint32_t flags = 0;
1152 
1153 	/*
1154 	 * The relevant bits are in different locations on their
1155 	 * CQE fields therefore we can join them in one 32bit
1156 	 * variable.
1157 	 */
1158 	if (csum)
1159 		flags = (rte_be_to_cpu_32(cqe->status) &
1160 			 MLX4_CQE_STATUS_IPV4_CSUM_OK);
1161 	if (csum_l2tun)
1162 		flags |= (rte_be_to_cpu_32(cqe->vlan_my_qpn) &
1163 			  (MLX4_CQE_L2_TUNNEL |
1164 			   MLX4_CQE_L2_TUNNEL_IPOK |
1165 			   MLX4_CQE_L2_TUNNEL_L4_CSUM |
1166 			   MLX4_CQE_L2_TUNNEL_IPV4));
1167 	return flags;
1168 }
1169 
1170 /**
1171  * Poll one CQE from CQ.
1172  *
1173  * @param rxq
1174  *   Pointer to the receive queue structure.
1175  * @param[out] out
1176  *   Just polled CQE.
1177  *
1178  * @return
1179  *   Number of bytes of the CQE, 0 in case there is no completion.
1180  */
1181 static unsigned int
1182 mlx4_cq_poll_one(struct rxq *rxq, volatile struct mlx4_cqe **out)
1183 {
1184 	int ret = 0;
1185 	volatile struct mlx4_cqe *cqe = NULL;
1186 	struct mlx4_cq *cq = &rxq->mcq;
1187 
1188 	cqe = (volatile struct mlx4_cqe *)mlx4_get_cqe(cq, cq->cons_index);
1189 	if (!!(cqe->owner_sr_opcode & MLX4_CQE_OWNER_MASK) ^
1190 	    !!(cq->cons_index & cq->cqe_cnt))
1191 		goto out;
1192 	/*
1193 	 * Make sure we read CQ entry contents after we've checked the
1194 	 * ownership bit.
1195 	 */
1196 	rte_rmb();
1197 	assert(!(cqe->owner_sr_opcode & MLX4_CQE_IS_SEND_MASK));
1198 	assert((cqe->owner_sr_opcode & MLX4_CQE_OPCODE_MASK) !=
1199 	       MLX4_CQE_OPCODE_ERROR);
1200 	ret = rte_be_to_cpu_32(cqe->byte_cnt);
1201 	++cq->cons_index;
1202 out:
1203 	*out = cqe;
1204 	return ret;
1205 }
1206 
1207 /**
1208  * DPDK callback for Rx with scattered packets support.
1209  *
1210  * @param dpdk_rxq
1211  *   Generic pointer to Rx queue structure.
1212  * @param[out] pkts
1213  *   Array to store received packets.
1214  * @param pkts_n
1215  *   Maximum number of packets in array.
1216  *
1217  * @return
1218  *   Number of packets successfully received (<= pkts_n).
1219  */
1220 uint16_t
1221 mlx4_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
1222 {
1223 	struct rxq *rxq = dpdk_rxq;
1224 	const uint32_t wr_cnt = (1 << rxq->elts_n) - 1;
1225 	const uint16_t sges_n = rxq->sges_n;
1226 	struct rte_mbuf *pkt = NULL;
1227 	struct rte_mbuf *seg = NULL;
1228 	unsigned int i = 0;
1229 	uint32_t rq_ci = rxq->rq_ci << sges_n;
1230 	int len = 0;
1231 
1232 	while (pkts_n) {
1233 		volatile struct mlx4_cqe *cqe;
1234 		uint32_t idx = rq_ci & wr_cnt;
1235 		struct rte_mbuf *rep = (*rxq->elts)[idx];
1236 		volatile struct mlx4_wqe_data_seg *scat = &(*rxq->wqes)[idx];
1237 
1238 		/* Update the 'next' pointer of the previous segment. */
1239 		if (pkt)
1240 			seg->next = rep;
1241 		seg = rep;
1242 		rte_prefetch0(seg);
1243 		rte_prefetch0(scat);
1244 		rep = rte_mbuf_raw_alloc(rxq->mp);
1245 		if (unlikely(rep == NULL)) {
1246 			++rxq->stats.rx_nombuf;
1247 			if (!pkt) {
1248 				/*
1249 				 * No buffers before we even started,
1250 				 * bail out silently.
1251 				 */
1252 				break;
1253 			}
1254 			while (pkt != seg) {
1255 				assert(pkt != (*rxq->elts)[idx]);
1256 				rep = pkt->next;
1257 				pkt->next = NULL;
1258 				pkt->nb_segs = 1;
1259 				rte_mbuf_raw_free(pkt);
1260 				pkt = rep;
1261 			}
1262 			break;
1263 		}
1264 		if (!pkt) {
1265 			/* Looking for the new packet. */
1266 			len = mlx4_cq_poll_one(rxq, &cqe);
1267 			if (!len) {
1268 				rte_mbuf_raw_free(rep);
1269 				break;
1270 			}
1271 			if (unlikely(len < 0)) {
1272 				/* Rx error, packet is likely too large. */
1273 				rte_mbuf_raw_free(rep);
1274 				++rxq->stats.idropped;
1275 				goto skip;
1276 			}
1277 			pkt = seg;
1278 			assert(len >= (rxq->crc_present << 2));
1279 			/* Update packet information. */
1280 			pkt->packet_type =
1281 				rxq_cq_to_pkt_type(cqe, rxq->l2tun_offload);
1282 			pkt->ol_flags = PKT_RX_RSS_HASH;
1283 			pkt->hash.rss = cqe->immed_rss_invalid;
1284 			if (rxq->crc_present)
1285 				len -= RTE_ETHER_CRC_LEN;
1286 			pkt->pkt_len = len;
1287 			if (rxq->csum | rxq->csum_l2tun) {
1288 				uint32_t flags =
1289 					mlx4_cqe_flags(cqe,
1290 						       rxq->csum,
1291 						       rxq->csum_l2tun);
1292 
1293 				pkt->ol_flags =
1294 					rxq_cq_to_ol_flags(flags,
1295 							   rxq->csum,
1296 							   rxq->csum_l2tun);
1297 			}
1298 		}
1299 		rep->nb_segs = 1;
1300 		rep->port = rxq->port_id;
1301 		rep->data_len = seg->data_len;
1302 		rep->data_off = seg->data_off;
1303 		(*rxq->elts)[idx] = rep;
1304 		/*
1305 		 * Fill NIC descriptor with the new buffer. The lkey and size
1306 		 * of the buffers are already known, only the buffer address
1307 		 * changes.
1308 		 */
1309 		scat->addr = rte_cpu_to_be_64(rte_pktmbuf_mtod(rep, uintptr_t));
1310 		/* If there's only one MR, no need to replace LKey in WQE. */
1311 		if (unlikely(mlx4_mr_btree_len(&rxq->mr_ctrl.cache_bh) > 1))
1312 			scat->lkey = mlx4_rx_mb2mr(rxq, rep);
1313 		if (len > seg->data_len) {
1314 			len -= seg->data_len;
1315 			++pkt->nb_segs;
1316 			++rq_ci;
1317 			continue;
1318 		}
1319 		/* The last segment. */
1320 		seg->data_len = len;
1321 		/* Increment bytes counter. */
1322 		rxq->stats.ibytes += pkt->pkt_len;
1323 		/* Return packet. */
1324 		*(pkts++) = pkt;
1325 		pkt = NULL;
1326 		--pkts_n;
1327 		++i;
1328 skip:
1329 		/* Align consumer index to the next stride. */
1330 		rq_ci >>= sges_n;
1331 		++rq_ci;
1332 		rq_ci <<= sges_n;
1333 	}
1334 	if (unlikely(i == 0 && (rq_ci >> sges_n) == rxq->rq_ci))
1335 		return 0;
1336 	/* Update the consumer index. */
1337 	rxq->rq_ci = rq_ci >> sges_n;
1338 	rte_wmb();
1339 	*rxq->rq_db = rte_cpu_to_be_32(rxq->rq_ci);
1340 	*rxq->mcq.set_ci_db =
1341 		rte_cpu_to_be_32(rxq->mcq.cons_index & MLX4_CQ_DB_CI_MASK);
1342 	/* Increment packets counter. */
1343 	rxq->stats.ipackets += i;
1344 	return i;
1345 }
1346 
1347 /**
1348  * Dummy DPDK callback for Tx.
1349  *
1350  * This function is used to temporarily replace the real callback during
1351  * unsafe control operations on the queue, or in case of error.
1352  *
1353  * @param dpdk_txq
1354  *   Generic pointer to Tx queue structure.
1355  * @param[in] pkts
1356  *   Packets to transmit.
1357  * @param pkts_n
1358  *   Number of packets in array.
1359  *
1360  * @return
1361  *   Number of packets successfully transmitted (<= pkts_n).
1362  */
1363 uint16_t
1364 mlx4_tx_burst_removed(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
1365 {
1366 	(void)dpdk_txq;
1367 	(void)pkts;
1368 	(void)pkts_n;
1369 	rte_mb();
1370 	return 0;
1371 }
1372 
1373 /**
1374  * Dummy DPDK callback for Rx.
1375  *
1376  * This function is used to temporarily replace the real callback during
1377  * unsafe control operations on the queue, or in case of error.
1378  *
1379  * @param dpdk_rxq
1380  *   Generic pointer to Rx queue structure.
1381  * @param[out] pkts
1382  *   Array to store received packets.
1383  * @param pkts_n
1384  *   Maximum number of packets in array.
1385  *
1386  * @return
1387  *   Number of packets successfully received (<= pkts_n).
1388  */
1389 uint16_t
1390 mlx4_rx_burst_removed(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
1391 {
1392 	(void)dpdk_rxq;
1393 	(void)pkts;
1394 	(void)pkts_n;
1395 	rte_mb();
1396 	return 0;
1397 }
1398