1 /*******************************************************************************
2 *
3 * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver
4 * Copyright(c) 2013 - 2014 Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program. If not, see <http://www.gnu.org/licenses/>.
17 *
18 * The full GNU General Public License is included in this distribution in
19 * the file called "COPYING".
20 *
21 * Contact Information:
22 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24 *
25 ******************************************************************************/
26
27 #include <linux/prefetch.h>
28 #include <net/busy_poll.h>
29
30 #include "i40evf.h"
31 #include "i40e_prototype.h"
32
build_ctob(u32 td_cmd,u32 td_offset,unsigned int size,u32 td_tag)33 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
34 u32 td_tag)
35 {
36 return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
37 ((u64)td_cmd << I40E_TXD_QW1_CMD_SHIFT) |
38 ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
39 ((u64)size << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
40 ((u64)td_tag << I40E_TXD_QW1_L2TAG1_SHIFT));
41 }
42
43 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
44
45 /**
46 * i40e_unmap_and_free_tx_resource - Release a Tx buffer
47 * @ring: the ring that owns the buffer
48 * @tx_buffer: the buffer to free
49 **/
i40e_unmap_and_free_tx_resource(struct i40e_ring * ring,struct i40e_tx_buffer * tx_buffer)50 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
51 struct i40e_tx_buffer *tx_buffer)
52 {
53 if (tx_buffer->skb) {
54 if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
55 kfree(tx_buffer->raw_buf);
56 else
57 dev_kfree_skb_any(tx_buffer->skb);
58
59 if (dma_unmap_len(tx_buffer, len))
60 dma_unmap_single(ring->dev,
61 dma_unmap_addr(tx_buffer, dma),
62 dma_unmap_len(tx_buffer, len),
63 DMA_TO_DEVICE);
64 } else if (dma_unmap_len(tx_buffer, len)) {
65 dma_unmap_page(ring->dev,
66 dma_unmap_addr(tx_buffer, dma),
67 dma_unmap_len(tx_buffer, len),
68 DMA_TO_DEVICE);
69 }
70 tx_buffer->next_to_watch = NULL;
71 tx_buffer->skb = NULL;
72 dma_unmap_len_set(tx_buffer, len, 0);
73 /* tx_buffer must be completely set up in the transmit path */
74 }
75
76 /**
77 * i40evf_clean_tx_ring - Free any empty Tx buffers
78 * @tx_ring: ring to be cleaned
79 **/
i40evf_clean_tx_ring(struct i40e_ring * tx_ring)80 void i40evf_clean_tx_ring(struct i40e_ring *tx_ring)
81 {
82 unsigned long bi_size;
83 u16 i;
84
85 /* ring already cleared, nothing to do */
86 if (!tx_ring->tx_bi)
87 return;
88
89 /* Free all the Tx ring sk_buffs */
90 for (i = 0; i < tx_ring->count; i++)
91 i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
92
93 bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
94 memset(tx_ring->tx_bi, 0, bi_size);
95
96 /* Zero out the descriptor ring */
97 memset(tx_ring->desc, 0, tx_ring->size);
98
99 tx_ring->next_to_use = 0;
100 tx_ring->next_to_clean = 0;
101
102 if (!tx_ring->netdev)
103 return;
104
105 /* cleanup Tx queue statistics */
106 netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
107 tx_ring->queue_index));
108 }
109
110 /**
111 * i40evf_free_tx_resources - Free Tx resources per queue
112 * @tx_ring: Tx descriptor ring for a specific queue
113 *
114 * Free all transmit software resources
115 **/
i40evf_free_tx_resources(struct i40e_ring * tx_ring)116 void i40evf_free_tx_resources(struct i40e_ring *tx_ring)
117 {
118 i40evf_clean_tx_ring(tx_ring);
119 kfree(tx_ring->tx_bi);
120 tx_ring->tx_bi = NULL;
121
122 if (tx_ring->desc) {
123 dma_free_coherent(tx_ring->dev, tx_ring->size,
124 tx_ring->desc, tx_ring->dma);
125 tx_ring->desc = NULL;
126 }
127 }
128
129 /**
130 * i40e_get_head - Retrieve head from head writeback
131 * @tx_ring: tx ring to fetch head of
132 *
133 * Returns value of Tx ring head based on value stored
134 * in head write-back location
135 **/
i40e_get_head(struct i40e_ring * tx_ring)136 static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
137 {
138 void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
139
140 return le32_to_cpu(*(volatile __le32 *)head);
141 }
142
143 #define WB_STRIDE 0x3
144
145 /**
146 * i40e_clean_tx_irq - Reclaim resources after transmit completes
147 * @tx_ring: tx ring to clean
148 * @budget: how many cleans we're allowed
149 *
150 * Returns true if there's any budget left (e.g. the clean is finished)
151 **/
i40e_clean_tx_irq(struct i40e_ring * tx_ring,int budget)152 static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
153 {
154 u16 i = tx_ring->next_to_clean;
155 struct i40e_tx_buffer *tx_buf;
156 struct i40e_tx_desc *tx_head;
157 struct i40e_tx_desc *tx_desc;
158 unsigned int total_packets = 0;
159 unsigned int total_bytes = 0;
160
161 tx_buf = &tx_ring->tx_bi[i];
162 tx_desc = I40E_TX_DESC(tx_ring, i);
163 i -= tx_ring->count;
164
165 tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
166
167 do {
168 struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
169
170 /* if next_to_watch is not set then there is no work pending */
171 if (!eop_desc)
172 break;
173
174 /* prevent any other reads prior to eop_desc */
175 read_barrier_depends();
176
177 /* we have caught up to head, no work left to do */
178 if (tx_head == tx_desc)
179 break;
180
181 /* clear next_to_watch to prevent false hangs */
182 tx_buf->next_to_watch = NULL;
183
184 /* update the statistics for this packet */
185 total_bytes += tx_buf->bytecount;
186 total_packets += tx_buf->gso_segs;
187
188 /* free the skb */
189 dev_kfree_skb_any(tx_buf->skb);
190
191 /* unmap skb header data */
192 dma_unmap_single(tx_ring->dev,
193 dma_unmap_addr(tx_buf, dma),
194 dma_unmap_len(tx_buf, len),
195 DMA_TO_DEVICE);
196
197 /* clear tx_buffer data */
198 tx_buf->skb = NULL;
199 dma_unmap_len_set(tx_buf, len, 0);
200
201 /* unmap remaining buffers */
202 while (tx_desc != eop_desc) {
203
204 tx_buf++;
205 tx_desc++;
206 i++;
207 if (unlikely(!i)) {
208 i -= tx_ring->count;
209 tx_buf = tx_ring->tx_bi;
210 tx_desc = I40E_TX_DESC(tx_ring, 0);
211 }
212
213 /* unmap any remaining paged data */
214 if (dma_unmap_len(tx_buf, len)) {
215 dma_unmap_page(tx_ring->dev,
216 dma_unmap_addr(tx_buf, dma),
217 dma_unmap_len(tx_buf, len),
218 DMA_TO_DEVICE);
219 dma_unmap_len_set(tx_buf, len, 0);
220 }
221 }
222
223 /* move us one more past the eop_desc for start of next pkt */
224 tx_buf++;
225 tx_desc++;
226 i++;
227 if (unlikely(!i)) {
228 i -= tx_ring->count;
229 tx_buf = tx_ring->tx_bi;
230 tx_desc = I40E_TX_DESC(tx_ring, 0);
231 }
232
233 prefetch(tx_desc);
234
235 /* update budget accounting */
236 budget--;
237 } while (likely(budget));
238
239 i += tx_ring->count;
240 tx_ring->next_to_clean = i;
241 u64_stats_update_begin(&tx_ring->syncp);
242 tx_ring->stats.bytes += total_bytes;
243 tx_ring->stats.packets += total_packets;
244 u64_stats_update_end(&tx_ring->syncp);
245 tx_ring->q_vector->tx.total_bytes += total_bytes;
246 tx_ring->q_vector->tx.total_packets += total_packets;
247
248 /* check to see if there are any non-cache aligned descriptors
249 * waiting to be written back, and kick the hardware to force
250 * them to be written back in case of napi polling
251 */
252 if (budget &&
253 !((i & WB_STRIDE) == WB_STRIDE) &&
254 !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
255 (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
256 tx_ring->arm_wb = true;
257
258 netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
259 tx_ring->queue_index),
260 total_packets, total_bytes);
261
262 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
263 if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
264 (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
265 /* Make sure that anybody stopping the queue after this
266 * sees the new next_to_clean.
267 */
268 smp_mb();
269 if (__netif_subqueue_stopped(tx_ring->netdev,
270 tx_ring->queue_index) &&
271 !test_bit(__I40E_DOWN, &tx_ring->vsi->state)) {
272 netif_wake_subqueue(tx_ring->netdev,
273 tx_ring->queue_index);
274 ++tx_ring->tx_stats.restart_queue;
275 }
276 }
277
278 return !!budget;
279 }
280
281 /**
282 * i40evf_force_wb -Arm hardware to do a wb on noncache aligned descriptors
283 * @vsi: the VSI we care about
284 * @q_vector: the vector on which to force writeback
285 *
286 **/
i40evf_force_wb(struct i40e_vsi * vsi,struct i40e_q_vector * q_vector)287 static void i40evf_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
288 {
289 u16 flags = q_vector->tx.ring[0].flags;
290
291 if (flags & I40E_TXR_FLAGS_WB_ON_ITR) {
292 u32 val;
293
294 if (q_vector->arm_wb_state)
295 return;
296
297 val = I40E_VFINT_DYN_CTLN1_WB_ON_ITR_MASK;
298
299 wr32(&vsi->back->hw,
300 I40E_VFINT_DYN_CTLN1(q_vector->v_idx +
301 vsi->base_vector - 1),
302 val);
303 q_vector->arm_wb_state = true;
304 } else {
305 u32 val = I40E_VFINT_DYN_CTLN1_INTENA_MASK |
306 I40E_VFINT_DYN_CTLN1_ITR_INDX_MASK | /* set noitr */
307 I40E_VFINT_DYN_CTLN1_SWINT_TRIG_MASK |
308 I40E_VFINT_DYN_CTLN1_SW_ITR_INDX_ENA_MASK;
309 /* allow 00 to be written to the index */
310
311 wr32(&vsi->back->hw,
312 I40E_VFINT_DYN_CTLN1(q_vector->v_idx +
313 vsi->base_vector - 1), val);
314 }
315 }
316
317 /**
318 * i40e_set_new_dynamic_itr - Find new ITR level
319 * @rc: structure containing ring performance data
320 *
321 * Returns true if ITR changed, false if not
322 *
323 * Stores a new ITR value based on packets and byte counts during
324 * the last interrupt. The advantage of per interrupt computation
325 * is faster updates and more accurate ITR for the current traffic
326 * pattern. Constants in this function were computed based on
327 * theoretical maximum wire speed and thresholds were set based on
328 * testing data as well as attempting to minimize response time
329 * while increasing bulk throughput.
330 **/
i40e_set_new_dynamic_itr(struct i40e_ring_container * rc)331 static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
332 {
333 enum i40e_latency_range new_latency_range = rc->latency_range;
334 struct i40e_q_vector *qv = rc->ring->q_vector;
335 u32 new_itr = rc->itr;
336 int bytes_per_int;
337 int usecs;
338
339 if (rc->total_packets == 0 || !rc->itr)
340 return false;
341
342 /* simple throttlerate management
343 * 0-10MB/s lowest (50000 ints/s)
344 * 10-20MB/s low (20000 ints/s)
345 * 20-1249MB/s bulk (18000 ints/s)
346 * > 40000 Rx packets per second (8000 ints/s)
347 *
348 * The math works out because the divisor is in 10^(-6) which
349 * turns the bytes/us input value into MB/s values, but
350 * make sure to use usecs, as the register values written
351 * are in 2 usec increments in the ITR registers, and make sure
352 * to use the smoothed values that the countdown timer gives us.
353 */
354 usecs = (rc->itr << 1) * ITR_COUNTDOWN_START;
355 bytes_per_int = rc->total_bytes / usecs;
356
357 switch (new_latency_range) {
358 case I40E_LOWEST_LATENCY:
359 if (bytes_per_int > 10)
360 new_latency_range = I40E_LOW_LATENCY;
361 break;
362 case I40E_LOW_LATENCY:
363 if (bytes_per_int > 20)
364 new_latency_range = I40E_BULK_LATENCY;
365 else if (bytes_per_int <= 10)
366 new_latency_range = I40E_LOWEST_LATENCY;
367 break;
368 case I40E_BULK_LATENCY:
369 case I40E_ULTRA_LATENCY:
370 default:
371 if (bytes_per_int <= 20)
372 new_latency_range = I40E_LOW_LATENCY;
373 break;
374 }
375
376 /* this is to adjust RX more aggressively when streaming small
377 * packets. The value of 40000 was picked as it is just beyond
378 * what the hardware can receive per second if in low latency
379 * mode.
380 */
381 #define RX_ULTRA_PACKET_RATE 40000
382
383 if ((((rc->total_packets * 1000000) / usecs) > RX_ULTRA_PACKET_RATE) &&
384 (&qv->rx == rc))
385 new_latency_range = I40E_ULTRA_LATENCY;
386
387 rc->latency_range = new_latency_range;
388
389 switch (new_latency_range) {
390 case I40E_LOWEST_LATENCY:
391 new_itr = I40E_ITR_50K;
392 break;
393 case I40E_LOW_LATENCY:
394 new_itr = I40E_ITR_20K;
395 break;
396 case I40E_BULK_LATENCY:
397 new_itr = I40E_ITR_18K;
398 break;
399 case I40E_ULTRA_LATENCY:
400 new_itr = I40E_ITR_8K;
401 break;
402 default:
403 break;
404 }
405
406 rc->total_bytes = 0;
407 rc->total_packets = 0;
408
409 if (new_itr != rc->itr) {
410 rc->itr = new_itr;
411 return true;
412 }
413
414 return false;
415 }
416
417 /*
418 * i40evf_setup_tx_descriptors - Allocate the Tx descriptors
419 * @tx_ring: the tx ring to set up
420 *
421 * Return 0 on success, negative on error
422 **/
i40evf_setup_tx_descriptors(struct i40e_ring * tx_ring)423 int i40evf_setup_tx_descriptors(struct i40e_ring *tx_ring)
424 {
425 struct device *dev = tx_ring->dev;
426 int bi_size;
427
428 if (!dev)
429 return -ENOMEM;
430
431 /* warn if we are about to overwrite the pointer */
432 WARN_ON(tx_ring->tx_bi);
433 bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
434 tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
435 if (!tx_ring->tx_bi)
436 goto err;
437
438 /* round up to nearest 4K */
439 tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
440 /* add u32 for head writeback, align after this takes care of
441 * guaranteeing this is at least one cache line in size
442 */
443 tx_ring->size += sizeof(u32);
444 tx_ring->size = ALIGN(tx_ring->size, 4096);
445 tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
446 &tx_ring->dma, GFP_KERNEL);
447 if (!tx_ring->desc) {
448 dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
449 tx_ring->size);
450 goto err;
451 }
452
453 tx_ring->next_to_use = 0;
454 tx_ring->next_to_clean = 0;
455 return 0;
456
457 err:
458 kfree(tx_ring->tx_bi);
459 tx_ring->tx_bi = NULL;
460 return -ENOMEM;
461 }
462
463 /**
464 * i40evf_clean_rx_ring - Free Rx buffers
465 * @rx_ring: ring to be cleaned
466 **/
i40evf_clean_rx_ring(struct i40e_ring * rx_ring)467 void i40evf_clean_rx_ring(struct i40e_ring *rx_ring)
468 {
469 struct device *dev = rx_ring->dev;
470 struct i40e_rx_buffer *rx_bi;
471 unsigned long bi_size;
472 u16 i;
473
474 /* ring already cleared, nothing to do */
475 if (!rx_ring->rx_bi)
476 return;
477
478 if (ring_is_ps_enabled(rx_ring)) {
479 int bufsz = ALIGN(rx_ring->rx_hdr_len, 256) * rx_ring->count;
480
481 rx_bi = &rx_ring->rx_bi[0];
482 if (rx_bi->hdr_buf) {
483 dma_free_coherent(dev,
484 bufsz,
485 rx_bi->hdr_buf,
486 rx_bi->dma);
487 for (i = 0; i < rx_ring->count; i++) {
488 rx_bi = &rx_ring->rx_bi[i];
489 rx_bi->dma = 0;
490 rx_bi->hdr_buf = NULL;
491 }
492 }
493 }
494 /* Free all the Rx ring sk_buffs */
495 for (i = 0; i < rx_ring->count; i++) {
496 rx_bi = &rx_ring->rx_bi[i];
497 if (rx_bi->dma) {
498 dma_unmap_single(dev,
499 rx_bi->dma,
500 rx_ring->rx_buf_len,
501 DMA_FROM_DEVICE);
502 rx_bi->dma = 0;
503 }
504 if (rx_bi->skb) {
505 dev_kfree_skb(rx_bi->skb);
506 rx_bi->skb = NULL;
507 }
508 if (rx_bi->page) {
509 if (rx_bi->page_dma) {
510 dma_unmap_page(dev,
511 rx_bi->page_dma,
512 PAGE_SIZE / 2,
513 DMA_FROM_DEVICE);
514 rx_bi->page_dma = 0;
515 }
516 __free_page(rx_bi->page);
517 rx_bi->page = NULL;
518 rx_bi->page_offset = 0;
519 }
520 }
521
522 bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
523 memset(rx_ring->rx_bi, 0, bi_size);
524
525 /* Zero out the descriptor ring */
526 memset(rx_ring->desc, 0, rx_ring->size);
527
528 rx_ring->next_to_clean = 0;
529 rx_ring->next_to_use = 0;
530 }
531
532 /**
533 * i40evf_free_rx_resources - Free Rx resources
534 * @rx_ring: ring to clean the resources from
535 *
536 * Free all receive software resources
537 **/
i40evf_free_rx_resources(struct i40e_ring * rx_ring)538 void i40evf_free_rx_resources(struct i40e_ring *rx_ring)
539 {
540 i40evf_clean_rx_ring(rx_ring);
541 kfree(rx_ring->rx_bi);
542 rx_ring->rx_bi = NULL;
543
544 if (rx_ring->desc) {
545 dma_free_coherent(rx_ring->dev, rx_ring->size,
546 rx_ring->desc, rx_ring->dma);
547 rx_ring->desc = NULL;
548 }
549 }
550
551 /**
552 * i40evf_alloc_rx_headers - allocate rx header buffers
553 * @rx_ring: ring to alloc buffers
554 *
555 * Allocate rx header buffers for the entire ring. As these are static,
556 * this is only called when setting up a new ring.
557 **/
i40evf_alloc_rx_headers(struct i40e_ring * rx_ring)558 void i40evf_alloc_rx_headers(struct i40e_ring *rx_ring)
559 {
560 struct device *dev = rx_ring->dev;
561 struct i40e_rx_buffer *rx_bi;
562 dma_addr_t dma;
563 void *buffer;
564 int buf_size;
565 int i;
566
567 if (rx_ring->rx_bi[0].hdr_buf)
568 return;
569 /* Make sure the buffers don't cross cache line boundaries. */
570 buf_size = ALIGN(rx_ring->rx_hdr_len, 256);
571 buffer = dma_alloc_coherent(dev, buf_size * rx_ring->count,
572 &dma, GFP_KERNEL);
573 if (!buffer)
574 return;
575 for (i = 0; i < rx_ring->count; i++) {
576 rx_bi = &rx_ring->rx_bi[i];
577 rx_bi->dma = dma + (i * buf_size);
578 rx_bi->hdr_buf = buffer + (i * buf_size);
579 }
580 }
581
582 /**
583 * i40evf_setup_rx_descriptors - Allocate Rx descriptors
584 * @rx_ring: Rx descriptor ring (for a specific queue) to setup
585 *
586 * Returns 0 on success, negative on failure
587 **/
i40evf_setup_rx_descriptors(struct i40e_ring * rx_ring)588 int i40evf_setup_rx_descriptors(struct i40e_ring *rx_ring)
589 {
590 struct device *dev = rx_ring->dev;
591 int bi_size;
592
593 /* warn if we are about to overwrite the pointer */
594 WARN_ON(rx_ring->rx_bi);
595 bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
596 rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
597 if (!rx_ring->rx_bi)
598 goto err;
599
600 u64_stats_init(&rx_ring->syncp);
601
602 /* Round up to nearest 4K */
603 rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
604 ? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
605 : rx_ring->count * sizeof(union i40e_32byte_rx_desc);
606 rx_ring->size = ALIGN(rx_ring->size, 4096);
607 rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
608 &rx_ring->dma, GFP_KERNEL);
609
610 if (!rx_ring->desc) {
611 dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
612 rx_ring->size);
613 goto err;
614 }
615
616 rx_ring->next_to_clean = 0;
617 rx_ring->next_to_use = 0;
618
619 return 0;
620 err:
621 kfree(rx_ring->rx_bi);
622 rx_ring->rx_bi = NULL;
623 return -ENOMEM;
624 }
625
626 /**
627 * i40e_release_rx_desc - Store the new tail and head values
628 * @rx_ring: ring to bump
629 * @val: new head index
630 **/
i40e_release_rx_desc(struct i40e_ring * rx_ring,u32 val)631 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
632 {
633 rx_ring->next_to_use = val;
634 /* Force memory writes to complete before letting h/w
635 * know there are new descriptors to fetch. (Only
636 * applicable for weak-ordered memory model archs,
637 * such as IA-64).
638 */
639 wmb();
640 writel(val, rx_ring->tail);
641 }
642
643 /**
644 * i40evf_alloc_rx_buffers_ps - Replace used receive buffers; packet split
645 * @rx_ring: ring to place buffers on
646 * @cleaned_count: number of buffers to replace
647 **/
i40evf_alloc_rx_buffers_ps(struct i40e_ring * rx_ring,u16 cleaned_count)648 void i40evf_alloc_rx_buffers_ps(struct i40e_ring *rx_ring, u16 cleaned_count)
649 {
650 u16 i = rx_ring->next_to_use;
651 union i40e_rx_desc *rx_desc;
652 struct i40e_rx_buffer *bi;
653
654 /* do nothing if no valid netdev defined */
655 if (!rx_ring->netdev || !cleaned_count)
656 return;
657
658 while (cleaned_count--) {
659 rx_desc = I40E_RX_DESC(rx_ring, i);
660 bi = &rx_ring->rx_bi[i];
661
662 if (bi->skb) /* desc is in use */
663 goto no_buffers;
664 if (!bi->page) {
665 bi->page = alloc_page(GFP_ATOMIC);
666 if (!bi->page) {
667 rx_ring->rx_stats.alloc_page_failed++;
668 goto no_buffers;
669 }
670 }
671
672 if (!bi->page_dma) {
673 /* use a half page if we're re-using */
674 bi->page_offset ^= PAGE_SIZE / 2;
675 bi->page_dma = dma_map_page(rx_ring->dev,
676 bi->page,
677 bi->page_offset,
678 PAGE_SIZE / 2,
679 DMA_FROM_DEVICE);
680 if (dma_mapping_error(rx_ring->dev,
681 bi->page_dma)) {
682 rx_ring->rx_stats.alloc_page_failed++;
683 bi->page_dma = 0;
684 goto no_buffers;
685 }
686 }
687
688 dma_sync_single_range_for_device(rx_ring->dev,
689 bi->dma,
690 0,
691 rx_ring->rx_hdr_len,
692 DMA_FROM_DEVICE);
693 /* Refresh the desc even if buffer_addrs didn't change
694 * because each write-back erases this info.
695 */
696 rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
697 rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
698 i++;
699 if (i == rx_ring->count)
700 i = 0;
701 }
702
703 no_buffers:
704 if (rx_ring->next_to_use != i)
705 i40e_release_rx_desc(rx_ring, i);
706 }
707
708 /**
709 * i40evf_alloc_rx_buffers_1buf - Replace used receive buffers; single buffer
710 * @rx_ring: ring to place buffers on
711 * @cleaned_count: number of buffers to replace
712 **/
i40evf_alloc_rx_buffers_1buf(struct i40e_ring * rx_ring,u16 cleaned_count)713 void i40evf_alloc_rx_buffers_1buf(struct i40e_ring *rx_ring, u16 cleaned_count)
714 {
715 u16 i = rx_ring->next_to_use;
716 union i40e_rx_desc *rx_desc;
717 struct i40e_rx_buffer *bi;
718 struct sk_buff *skb;
719
720 /* do nothing if no valid netdev defined */
721 if (!rx_ring->netdev || !cleaned_count)
722 return;
723
724 while (cleaned_count--) {
725 rx_desc = I40E_RX_DESC(rx_ring, i);
726 bi = &rx_ring->rx_bi[i];
727 skb = bi->skb;
728
729 if (!skb) {
730 skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
731 rx_ring->rx_buf_len);
732 if (!skb) {
733 rx_ring->rx_stats.alloc_buff_failed++;
734 goto no_buffers;
735 }
736 /* initialize queue mapping */
737 skb_record_rx_queue(skb, rx_ring->queue_index);
738 bi->skb = skb;
739 }
740
741 if (!bi->dma) {
742 bi->dma = dma_map_single(rx_ring->dev,
743 skb->data,
744 rx_ring->rx_buf_len,
745 DMA_FROM_DEVICE);
746 if (dma_mapping_error(rx_ring->dev, bi->dma)) {
747 rx_ring->rx_stats.alloc_buff_failed++;
748 bi->dma = 0;
749 goto no_buffers;
750 }
751 }
752
753 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
754 rx_desc->read.hdr_addr = 0;
755 i++;
756 if (i == rx_ring->count)
757 i = 0;
758 }
759
760 no_buffers:
761 if (rx_ring->next_to_use != i)
762 i40e_release_rx_desc(rx_ring, i);
763 }
764
765 /**
766 * i40e_receive_skb - Send a completed packet up the stack
767 * @rx_ring: rx ring in play
768 * @skb: packet to send up
769 * @vlan_tag: vlan tag for packet
770 **/
i40e_receive_skb(struct i40e_ring * rx_ring,struct sk_buff * skb,u16 vlan_tag)771 static void i40e_receive_skb(struct i40e_ring *rx_ring,
772 struct sk_buff *skb, u16 vlan_tag)
773 {
774 struct i40e_q_vector *q_vector = rx_ring->q_vector;
775
776 if (vlan_tag & VLAN_VID_MASK)
777 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
778
779 napi_gro_receive(&q_vector->napi, skb);
780 }
781
782 /**
783 * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
784 * @vsi: the VSI we care about
785 * @skb: skb currently being received and modified
786 * @rx_status: status value of last descriptor in packet
787 * @rx_error: error value of last descriptor in packet
788 * @rx_ptype: ptype value of last descriptor in packet
789 **/
i40e_rx_checksum(struct i40e_vsi * vsi,struct sk_buff * skb,u32 rx_status,u32 rx_error,u16 rx_ptype)790 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
791 struct sk_buff *skb,
792 u32 rx_status,
793 u32 rx_error,
794 u16 rx_ptype)
795 {
796 struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(rx_ptype);
797 bool ipv4 = false, ipv6 = false;
798 bool ipv4_tunnel, ipv6_tunnel;
799 __wsum rx_udp_csum;
800 struct iphdr *iph;
801 __sum16 csum;
802
803 ipv4_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT4_MAC_PAY3) &&
804 (rx_ptype <= I40E_RX_PTYPE_GRENAT4_MACVLAN_IPV6_ICMP_PAY4);
805 ipv6_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT6_MAC_PAY3) &&
806 (rx_ptype <= I40E_RX_PTYPE_GRENAT6_MACVLAN_IPV6_ICMP_PAY4);
807
808 skb->ip_summed = CHECKSUM_NONE;
809
810 /* Rx csum enabled and ip headers found? */
811 if (!(vsi->netdev->features & NETIF_F_RXCSUM))
812 return;
813
814 /* did the hardware decode the packet and checksum? */
815 if (!(rx_status & BIT(I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
816 return;
817
818 /* both known and outer_ip must be set for the below code to work */
819 if (!(decoded.known && decoded.outer_ip))
820 return;
821
822 if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
823 decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4)
824 ipv4 = true;
825 else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
826 decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6)
827 ipv6 = true;
828
829 if (ipv4 &&
830 (rx_error & (BIT(I40E_RX_DESC_ERROR_IPE_SHIFT) |
831 BIT(I40E_RX_DESC_ERROR_EIPE_SHIFT))))
832 goto checksum_fail;
833
834 /* likely incorrect csum if alternate IP extension headers found */
835 if (ipv6 &&
836 rx_status & BIT(I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
837 /* don't increment checksum err here, non-fatal err */
838 return;
839
840 /* there was some L4 error, count error and punt packet to the stack */
841 if (rx_error & BIT(I40E_RX_DESC_ERROR_L4E_SHIFT))
842 goto checksum_fail;
843
844 /* handle packets that were not able to be checksummed due
845 * to arrival speed, in this case the stack can compute
846 * the csum.
847 */
848 if (rx_error & BIT(I40E_RX_DESC_ERROR_PPRS_SHIFT))
849 return;
850
851 /* If VXLAN traffic has an outer UDPv4 checksum we need to check
852 * it in the driver, hardware does not do it for us.
853 * Since L3L4P bit was set we assume a valid IHL value (>=5)
854 * so the total length of IPv4 header is IHL*4 bytes
855 * The UDP_0 bit *may* bet set if the *inner* header is UDP
856 */
857 if (ipv4_tunnel) {
858 skb->transport_header = skb->mac_header +
859 sizeof(struct ethhdr) +
860 (ip_hdr(skb)->ihl * 4);
861
862 /* Add 4 bytes for VLAN tagged packets */
863 skb->transport_header += (skb->protocol == htons(ETH_P_8021Q) ||
864 skb->protocol == htons(ETH_P_8021AD))
865 ? VLAN_HLEN : 0;
866
867 if ((ip_hdr(skb)->protocol == IPPROTO_UDP) &&
868 (udp_hdr(skb)->check != 0)) {
869 rx_udp_csum = udp_csum(skb);
870 iph = ip_hdr(skb);
871 csum = csum_tcpudp_magic(iph->saddr, iph->daddr,
872 (skb->len -
873 skb_transport_offset(skb)),
874 IPPROTO_UDP, rx_udp_csum);
875
876 if (udp_hdr(skb)->check != csum)
877 goto checksum_fail;
878
879 } /* else its GRE and so no outer UDP header */
880 }
881
882 skb->ip_summed = CHECKSUM_UNNECESSARY;
883 skb->csum_level = ipv4_tunnel || ipv6_tunnel;
884
885 return;
886
887 checksum_fail:
888 vsi->back->hw_csum_rx_error++;
889 }
890
891 /**
892 * i40e_rx_hash - returns the hash value from the Rx descriptor
893 * @ring: descriptor ring
894 * @rx_desc: specific descriptor
895 **/
i40e_rx_hash(struct i40e_ring * ring,union i40e_rx_desc * rx_desc)896 static inline u32 i40e_rx_hash(struct i40e_ring *ring,
897 union i40e_rx_desc *rx_desc)
898 {
899 const __le64 rss_mask =
900 cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
901 I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
902
903 if ((ring->netdev->features & NETIF_F_RXHASH) &&
904 (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
905 return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
906 else
907 return 0;
908 }
909
910 /**
911 * i40e_ptype_to_hash - get a hash type
912 * @ptype: the ptype value from the descriptor
913 *
914 * Returns a hash type to be used by skb_set_hash
915 **/
i40e_ptype_to_hash(u8 ptype)916 static inline enum pkt_hash_types i40e_ptype_to_hash(u8 ptype)
917 {
918 struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
919
920 if (!decoded.known)
921 return PKT_HASH_TYPE_NONE;
922
923 if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
924 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
925 return PKT_HASH_TYPE_L4;
926 else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
927 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
928 return PKT_HASH_TYPE_L3;
929 else
930 return PKT_HASH_TYPE_L2;
931 }
932
933 /**
934 * i40e_clean_rx_irq_ps - Reclaim resources after receive; packet split
935 * @rx_ring: rx ring to clean
936 * @budget: how many cleans we're allowed
937 *
938 * Returns true if there's any budget left (e.g. the clean is finished)
939 **/
i40e_clean_rx_irq_ps(struct i40e_ring * rx_ring,int budget)940 static int i40e_clean_rx_irq_ps(struct i40e_ring *rx_ring, int budget)
941 {
942 unsigned int total_rx_bytes = 0, total_rx_packets = 0;
943 u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
944 u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
945 const int current_node = numa_mem_id();
946 struct i40e_vsi *vsi = rx_ring->vsi;
947 u16 i = rx_ring->next_to_clean;
948 union i40e_rx_desc *rx_desc;
949 u32 rx_error, rx_status;
950 u8 rx_ptype;
951 u64 qword;
952
953 do {
954 struct i40e_rx_buffer *rx_bi;
955 struct sk_buff *skb;
956 u16 vlan_tag;
957 /* return some buffers to hardware, one at a time is too slow */
958 if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
959 i40evf_alloc_rx_buffers_ps(rx_ring, cleaned_count);
960 cleaned_count = 0;
961 }
962
963 i = rx_ring->next_to_clean;
964 rx_desc = I40E_RX_DESC(rx_ring, i);
965 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
966 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
967 I40E_RXD_QW1_STATUS_SHIFT;
968
969 if (!(rx_status & BIT(I40E_RX_DESC_STATUS_DD_SHIFT)))
970 break;
971
972 /* This memory barrier is needed to keep us from reading
973 * any other fields out of the rx_desc until we know the
974 * DD bit is set.
975 */
976 dma_rmb();
977 rx_bi = &rx_ring->rx_bi[i];
978 skb = rx_bi->skb;
979 if (likely(!skb)) {
980 skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
981 rx_ring->rx_hdr_len);
982 if (!skb) {
983 rx_ring->rx_stats.alloc_buff_failed++;
984 break;
985 }
986
987 /* initialize queue mapping */
988 skb_record_rx_queue(skb, rx_ring->queue_index);
989 /* we are reusing so sync this buffer for CPU use */
990 dma_sync_single_range_for_cpu(rx_ring->dev,
991 rx_bi->dma,
992 0,
993 rx_ring->rx_hdr_len,
994 DMA_FROM_DEVICE);
995 }
996 rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
997 I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
998 rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK) >>
999 I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
1000 rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK) >>
1001 I40E_RXD_QW1_LENGTH_SPH_SHIFT;
1002
1003 rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1004 I40E_RXD_QW1_ERROR_SHIFT;
1005 rx_hbo = rx_error & BIT(I40E_RX_DESC_ERROR_HBO_SHIFT);
1006 rx_error &= ~BIT(I40E_RX_DESC_ERROR_HBO_SHIFT);
1007
1008 rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1009 I40E_RXD_QW1_PTYPE_SHIFT;
1010 prefetch(rx_bi->page);
1011 rx_bi->skb = NULL;
1012 cleaned_count++;
1013 if (rx_hbo || rx_sph) {
1014 int len;
1015
1016 if (rx_hbo)
1017 len = I40E_RX_HDR_SIZE;
1018 else
1019 len = rx_header_len;
1020 memcpy(__skb_put(skb, len), rx_bi->hdr_buf, len);
1021 } else if (skb->len == 0) {
1022 int len;
1023
1024 len = (rx_packet_len > skb_headlen(skb) ?
1025 skb_headlen(skb) : rx_packet_len);
1026 memcpy(__skb_put(skb, len),
1027 rx_bi->page + rx_bi->page_offset,
1028 len);
1029 rx_bi->page_offset += len;
1030 rx_packet_len -= len;
1031 }
1032
1033 /* Get the rest of the data if this was a header split */
1034 if (rx_packet_len) {
1035 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
1036 rx_bi->page,
1037 rx_bi->page_offset,
1038 rx_packet_len);
1039
1040 skb->len += rx_packet_len;
1041 skb->data_len += rx_packet_len;
1042 skb->truesize += rx_packet_len;
1043
1044 if ((page_count(rx_bi->page) == 1) &&
1045 (page_to_nid(rx_bi->page) == current_node))
1046 get_page(rx_bi->page);
1047 else
1048 rx_bi->page = NULL;
1049
1050 dma_unmap_page(rx_ring->dev,
1051 rx_bi->page_dma,
1052 PAGE_SIZE / 2,
1053 DMA_FROM_DEVICE);
1054 rx_bi->page_dma = 0;
1055 }
1056 I40E_RX_INCREMENT(rx_ring, i);
1057
1058 if (unlikely(
1059 !(rx_status & BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1060 struct i40e_rx_buffer *next_buffer;
1061
1062 next_buffer = &rx_ring->rx_bi[i];
1063 next_buffer->skb = skb;
1064 rx_ring->rx_stats.non_eop_descs++;
1065 continue;
1066 }
1067
1068 /* ERR_MASK will only have valid bits if EOP set */
1069 if (unlikely(rx_error & BIT(I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1070 dev_kfree_skb_any(skb);
1071 continue;
1072 }
1073
1074 skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1075 i40e_ptype_to_hash(rx_ptype));
1076 /* probably a little skewed due to removing CRC */
1077 total_rx_bytes += skb->len;
1078 total_rx_packets++;
1079
1080 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1081
1082 i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1083
1084 vlan_tag = rx_status & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1085 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1086 : 0;
1087 #ifdef I40E_FCOE
1088 if (!i40e_fcoe_handle_offload(rx_ring, rx_desc, skb)) {
1089 dev_kfree_skb_any(skb);
1090 continue;
1091 }
1092 #endif
1093 skb_mark_napi_id(skb, &rx_ring->q_vector->napi);
1094 i40e_receive_skb(rx_ring, skb, vlan_tag);
1095
1096 rx_desc->wb.qword1.status_error_len = 0;
1097
1098 } while (likely(total_rx_packets < budget));
1099
1100 u64_stats_update_begin(&rx_ring->syncp);
1101 rx_ring->stats.packets += total_rx_packets;
1102 rx_ring->stats.bytes += total_rx_bytes;
1103 u64_stats_update_end(&rx_ring->syncp);
1104 rx_ring->q_vector->rx.total_packets += total_rx_packets;
1105 rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1106
1107 return total_rx_packets;
1108 }
1109
1110 /**
1111 * i40e_clean_rx_irq_1buf - Reclaim resources after receive; single buffer
1112 * @rx_ring: rx ring to clean
1113 * @budget: how many cleans we're allowed
1114 *
1115 * Returns number of packets cleaned
1116 **/
i40e_clean_rx_irq_1buf(struct i40e_ring * rx_ring,int budget)1117 static int i40e_clean_rx_irq_1buf(struct i40e_ring *rx_ring, int budget)
1118 {
1119 unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1120 u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1121 struct i40e_vsi *vsi = rx_ring->vsi;
1122 union i40e_rx_desc *rx_desc;
1123 u32 rx_error, rx_status;
1124 u16 rx_packet_len;
1125 u8 rx_ptype;
1126 u64 qword;
1127 u16 i;
1128
1129 do {
1130 struct i40e_rx_buffer *rx_bi;
1131 struct sk_buff *skb;
1132 u16 vlan_tag;
1133 /* return some buffers to hardware, one at a time is too slow */
1134 if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1135 i40evf_alloc_rx_buffers_1buf(rx_ring, cleaned_count);
1136 cleaned_count = 0;
1137 }
1138
1139 i = rx_ring->next_to_clean;
1140 rx_desc = I40E_RX_DESC(rx_ring, i);
1141 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1142 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1143 I40E_RXD_QW1_STATUS_SHIFT;
1144
1145 if (!(rx_status & BIT(I40E_RX_DESC_STATUS_DD_SHIFT)))
1146 break;
1147
1148 /* This memory barrier is needed to keep us from reading
1149 * any other fields out of the rx_desc until we know the
1150 * DD bit is set.
1151 */
1152 dma_rmb();
1153
1154 rx_bi = &rx_ring->rx_bi[i];
1155 skb = rx_bi->skb;
1156 prefetch(skb->data);
1157
1158 rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
1159 I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
1160
1161 rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1162 I40E_RXD_QW1_ERROR_SHIFT;
1163 rx_error &= ~BIT(I40E_RX_DESC_ERROR_HBO_SHIFT);
1164
1165 rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1166 I40E_RXD_QW1_PTYPE_SHIFT;
1167 rx_bi->skb = NULL;
1168 cleaned_count++;
1169
1170 /* Get the header and possibly the whole packet
1171 * If this is an skb from previous receive dma will be 0
1172 */
1173 skb_put(skb, rx_packet_len);
1174 dma_unmap_single(rx_ring->dev, rx_bi->dma, rx_ring->rx_buf_len,
1175 DMA_FROM_DEVICE);
1176 rx_bi->dma = 0;
1177
1178 I40E_RX_INCREMENT(rx_ring, i);
1179
1180 if (unlikely(
1181 !(rx_status & BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1182 rx_ring->rx_stats.non_eop_descs++;
1183 continue;
1184 }
1185
1186 /* ERR_MASK will only have valid bits if EOP set */
1187 if (unlikely(rx_error & BIT(I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1188 dev_kfree_skb_any(skb);
1189 continue;
1190 }
1191
1192 skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1193 i40e_ptype_to_hash(rx_ptype));
1194 /* probably a little skewed due to removing CRC */
1195 total_rx_bytes += skb->len;
1196 total_rx_packets++;
1197
1198 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1199
1200 i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1201
1202 vlan_tag = rx_status & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1203 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1204 : 0;
1205 i40e_receive_skb(rx_ring, skb, vlan_tag);
1206
1207 rx_desc->wb.qword1.status_error_len = 0;
1208 } while (likely(total_rx_packets < budget));
1209
1210 u64_stats_update_begin(&rx_ring->syncp);
1211 rx_ring->stats.packets += total_rx_packets;
1212 rx_ring->stats.bytes += total_rx_bytes;
1213 u64_stats_update_end(&rx_ring->syncp);
1214 rx_ring->q_vector->rx.total_packets += total_rx_packets;
1215 rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1216
1217 return total_rx_packets;
1218 }
1219
i40e_buildreg_itr(const int type,const u16 itr)1220 static u32 i40e_buildreg_itr(const int type, const u16 itr)
1221 {
1222 u32 val;
1223
1224 val = I40E_VFINT_DYN_CTLN1_INTENA_MASK |
1225 I40E_VFINT_DYN_CTLN1_CLEARPBA_MASK |
1226 (type << I40E_VFINT_DYN_CTLN1_ITR_INDX_SHIFT) |
1227 (itr << I40E_VFINT_DYN_CTLN1_INTERVAL_SHIFT);
1228
1229 return val;
1230 }
1231
1232 /* a small macro to shorten up some long lines */
1233 #define INTREG I40E_VFINT_DYN_CTLN1
1234
1235 /**
1236 * i40e_update_enable_itr - Update itr and re-enable MSIX interrupt
1237 * @vsi: the VSI we care about
1238 * @q_vector: q_vector for which itr is being updated and interrupt enabled
1239 *
1240 **/
i40e_update_enable_itr(struct i40e_vsi * vsi,struct i40e_q_vector * q_vector)1241 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
1242 struct i40e_q_vector *q_vector)
1243 {
1244 struct i40e_hw *hw = &vsi->back->hw;
1245 bool rx = false, tx = false;
1246 u32 rxval, txval;
1247 int vector;
1248
1249 vector = (q_vector->v_idx + vsi->base_vector);
1250
1251 /* avoid dynamic calculation if in countdown mode OR if
1252 * all dynamic is disabled
1253 */
1254 rxval = txval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
1255
1256 if (q_vector->itr_countdown > 0 ||
1257 (!ITR_IS_DYNAMIC(vsi->rx_itr_setting) &&
1258 !ITR_IS_DYNAMIC(vsi->tx_itr_setting))) {
1259 goto enable_int;
1260 }
1261
1262 if (ITR_IS_DYNAMIC(vsi->rx_itr_setting)) {
1263 rx = i40e_set_new_dynamic_itr(&q_vector->rx);
1264 rxval = i40e_buildreg_itr(I40E_RX_ITR, q_vector->rx.itr);
1265 }
1266 if (ITR_IS_DYNAMIC(vsi->tx_itr_setting)) {
1267 tx = i40e_set_new_dynamic_itr(&q_vector->tx);
1268 txval = i40e_buildreg_itr(I40E_TX_ITR, q_vector->tx.itr);
1269 }
1270 if (rx || tx) {
1271 /* get the higher of the two ITR adjustments and
1272 * use the same value for both ITR registers
1273 * when in adaptive mode (Rx and/or Tx)
1274 */
1275 u16 itr = max(q_vector->tx.itr, q_vector->rx.itr);
1276
1277 q_vector->tx.itr = q_vector->rx.itr = itr;
1278 txval = i40e_buildreg_itr(I40E_TX_ITR, itr);
1279 tx = true;
1280 rxval = i40e_buildreg_itr(I40E_RX_ITR, itr);
1281 rx = true;
1282 }
1283
1284 /* only need to enable the interrupt once, but need
1285 * to possibly update both ITR values
1286 */
1287 if (rx) {
1288 /* set the INTENA_MSK_MASK so that this first write
1289 * won't actually enable the interrupt, instead just
1290 * updating the ITR (it's bit 31 PF and VF)
1291 */
1292 rxval |= BIT(31);
1293 /* don't check _DOWN because interrupt isn't being enabled */
1294 wr32(hw, INTREG(vector - 1), rxval);
1295 }
1296
1297 enable_int:
1298 if (!test_bit(__I40E_DOWN, &vsi->state))
1299 wr32(hw, INTREG(vector - 1), txval);
1300
1301 if (q_vector->itr_countdown)
1302 q_vector->itr_countdown--;
1303 else
1304 q_vector->itr_countdown = ITR_COUNTDOWN_START;
1305
1306 }
1307
1308 /**
1309 * i40evf_napi_poll - NAPI polling Rx/Tx cleanup routine
1310 * @napi: napi struct with our devices info in it
1311 * @budget: amount of work driver is allowed to do this pass, in packets
1312 *
1313 * This function will clean all queues associated with a q_vector.
1314 *
1315 * Returns the amount of work done
1316 **/
i40evf_napi_poll(struct napi_struct * napi,int budget)1317 int i40evf_napi_poll(struct napi_struct *napi, int budget)
1318 {
1319 struct i40e_q_vector *q_vector =
1320 container_of(napi, struct i40e_q_vector, napi);
1321 struct i40e_vsi *vsi = q_vector->vsi;
1322 struct i40e_ring *ring;
1323 bool clean_complete = true;
1324 bool arm_wb = false;
1325 int budget_per_ring;
1326 int work_done = 0;
1327
1328 if (test_bit(__I40E_DOWN, &vsi->state)) {
1329 napi_complete(napi);
1330 return 0;
1331 }
1332
1333 /* Since the actual Tx work is minimal, we can give the Tx a larger
1334 * budget and be more aggressive about cleaning up the Tx descriptors.
1335 */
1336 i40e_for_each_ring(ring, q_vector->tx) {
1337 clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
1338 arm_wb |= ring->arm_wb;
1339 ring->arm_wb = false;
1340 }
1341
1342 /* Handle case where we are called by netpoll with a budget of 0 */
1343 if (budget <= 0)
1344 goto tx_only;
1345
1346 /* We attempt to distribute budget to each Rx queue fairly, but don't
1347 * allow the budget to go below 1 because that would exit polling early.
1348 */
1349 budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
1350
1351 i40e_for_each_ring(ring, q_vector->rx) {
1352 int cleaned;
1353
1354 if (ring_is_ps_enabled(ring))
1355 cleaned = i40e_clean_rx_irq_ps(ring, budget_per_ring);
1356 else
1357 cleaned = i40e_clean_rx_irq_1buf(ring, budget_per_ring);
1358
1359 work_done += cleaned;
1360 /* if we didn't clean as many as budgeted, we must be done */
1361 clean_complete &= (budget_per_ring != cleaned);
1362 }
1363
1364 /* If work not completed, return budget and polling will return */
1365 if (!clean_complete) {
1366 tx_only:
1367 if (arm_wb)
1368 i40evf_force_wb(vsi, q_vector);
1369 return budget;
1370 }
1371
1372 if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR)
1373 q_vector->arm_wb_state = false;
1374
1375 /* Work is done so exit the polling mode and re-enable the interrupt */
1376 napi_complete_done(napi, work_done);
1377 i40e_update_enable_itr(vsi, q_vector);
1378 return 0;
1379 }
1380
1381 /**
1382 * i40evf_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
1383 * @skb: send buffer
1384 * @tx_ring: ring to send buffer on
1385 * @flags: the tx flags to be set
1386 *
1387 * Checks the skb and set up correspondingly several generic transmit flags
1388 * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1389 *
1390 * Returns error code indicate the frame should be dropped upon error and the
1391 * otherwise returns 0 to indicate the flags has been set properly.
1392 **/
i40evf_tx_prepare_vlan_flags(struct sk_buff * skb,struct i40e_ring * tx_ring,u32 * flags)1393 static inline int i40evf_tx_prepare_vlan_flags(struct sk_buff *skb,
1394 struct i40e_ring *tx_ring,
1395 u32 *flags)
1396 {
1397 __be16 protocol = skb->protocol;
1398 u32 tx_flags = 0;
1399
1400 if (protocol == htons(ETH_P_8021Q) &&
1401 !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
1402 /* When HW VLAN acceleration is turned off by the user the
1403 * stack sets the protocol to 8021q so that the driver
1404 * can take any steps required to support the SW only
1405 * VLAN handling. In our case the driver doesn't need
1406 * to take any further steps so just set the protocol
1407 * to the encapsulated ethertype.
1408 */
1409 skb->protocol = vlan_get_protocol(skb);
1410 goto out;
1411 }
1412
1413 /* if we have a HW VLAN tag being added, default to the HW one */
1414 if (skb_vlan_tag_present(skb)) {
1415 tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
1416 tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1417 /* else if it is a SW VLAN, check the next protocol and store the tag */
1418 } else if (protocol == htons(ETH_P_8021Q)) {
1419 struct vlan_hdr *vhdr, _vhdr;
1420
1421 vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
1422 if (!vhdr)
1423 return -EINVAL;
1424
1425 protocol = vhdr->h_vlan_encapsulated_proto;
1426 tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
1427 tx_flags |= I40E_TX_FLAGS_SW_VLAN;
1428 }
1429
1430 out:
1431 *flags = tx_flags;
1432 return 0;
1433 }
1434
1435 /**
1436 * i40e_tso - set up the tso context descriptor
1437 * @tx_ring: ptr to the ring to send
1438 * @skb: ptr to the skb we're sending
1439 * @hdr_len: ptr to the size of the packet header
1440 * @cd_tunneling: ptr to context descriptor bits
1441 *
1442 * Returns 0 if no TSO can happen, 1 if tso is going, or error
1443 **/
i40e_tso(struct i40e_ring * tx_ring,struct sk_buff * skb,u8 * hdr_len,u64 * cd_type_cmd_tso_mss,u32 * cd_tunneling)1444 static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
1445 u8 *hdr_len, u64 *cd_type_cmd_tso_mss,
1446 u32 *cd_tunneling)
1447 {
1448 u32 cd_cmd, cd_tso_len, cd_mss;
1449 struct ipv6hdr *ipv6h;
1450 struct tcphdr *tcph;
1451 struct iphdr *iph;
1452 u32 l4len;
1453 int err;
1454
1455 if (!skb_is_gso(skb))
1456 return 0;
1457
1458 err = skb_cow_head(skb, 0);
1459 if (err < 0)
1460 return err;
1461
1462 iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
1463 ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
1464
1465 if (iph->version == 4) {
1466 tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1467 iph->tot_len = 0;
1468 iph->check = 0;
1469 tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
1470 0, IPPROTO_TCP, 0);
1471 } else if (ipv6h->version == 6) {
1472 tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1473 ipv6h->payload_len = 0;
1474 tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
1475 0, IPPROTO_TCP, 0);
1476 }
1477
1478 l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
1479 *hdr_len = (skb->encapsulation
1480 ? (skb_inner_transport_header(skb) - skb->data)
1481 : skb_transport_offset(skb)) + l4len;
1482
1483 /* find the field values */
1484 cd_cmd = I40E_TX_CTX_DESC_TSO;
1485 cd_tso_len = skb->len - *hdr_len;
1486 cd_mss = skb_shinfo(skb)->gso_size;
1487 *cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
1488 ((u64)cd_tso_len <<
1489 I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
1490 ((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
1491 return 1;
1492 }
1493
1494 /**
1495 * i40e_tx_enable_csum - Enable Tx checksum offloads
1496 * @skb: send buffer
1497 * @tx_flags: pointer to Tx flags currently set
1498 * @td_cmd: Tx descriptor command bits to set
1499 * @td_offset: Tx descriptor header offsets to set
1500 * @cd_tunneling: ptr to context desc bits
1501 **/
i40e_tx_enable_csum(struct sk_buff * skb,u32 * tx_flags,u32 * td_cmd,u32 * td_offset,struct i40e_ring * tx_ring,u32 * cd_tunneling)1502 static void i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
1503 u32 *td_cmd, u32 *td_offset,
1504 struct i40e_ring *tx_ring,
1505 u32 *cd_tunneling)
1506 {
1507 struct ipv6hdr *this_ipv6_hdr;
1508 unsigned int this_tcp_hdrlen;
1509 struct iphdr *this_ip_hdr;
1510 u32 network_hdr_len;
1511 u8 l4_hdr = 0;
1512 struct udphdr *oudph;
1513 struct iphdr *oiph;
1514 u32 l4_tunnel = 0;
1515
1516 if (skb->encapsulation) {
1517 switch (ip_hdr(skb)->protocol) {
1518 case IPPROTO_UDP:
1519 oudph = udp_hdr(skb);
1520 oiph = ip_hdr(skb);
1521 l4_tunnel = I40E_TXD_CTX_UDP_TUNNELING;
1522 *tx_flags |= I40E_TX_FLAGS_VXLAN_TUNNEL;
1523 break;
1524 default:
1525 return;
1526 }
1527 network_hdr_len = skb_inner_network_header_len(skb);
1528 this_ip_hdr = inner_ip_hdr(skb);
1529 this_ipv6_hdr = inner_ipv6_hdr(skb);
1530 this_tcp_hdrlen = inner_tcp_hdrlen(skb);
1531
1532 if (*tx_flags & I40E_TX_FLAGS_IPV4) {
1533 if (*tx_flags & I40E_TX_FLAGS_TSO) {
1534 *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
1535 ip_hdr(skb)->check = 0;
1536 } else {
1537 *cd_tunneling |=
1538 I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1539 }
1540 } else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
1541 *cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
1542 if (*tx_flags & I40E_TX_FLAGS_TSO)
1543 ip_hdr(skb)->check = 0;
1544 }
1545
1546 /* Now set the ctx descriptor fields */
1547 *cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
1548 I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
1549 l4_tunnel |
1550 ((skb_inner_network_offset(skb) -
1551 skb_transport_offset(skb)) >> 1) <<
1552 I40E_TXD_CTX_QW0_NATLEN_SHIFT;
1553 if (this_ip_hdr->version == 6) {
1554 *tx_flags &= ~I40E_TX_FLAGS_IPV4;
1555 *tx_flags |= I40E_TX_FLAGS_IPV6;
1556 }
1557
1558
1559 if ((tx_ring->flags & I40E_TXR_FLAGS_OUTER_UDP_CSUM) &&
1560 (l4_tunnel == I40E_TXD_CTX_UDP_TUNNELING) &&
1561 (*cd_tunneling & I40E_TXD_CTX_QW0_EXT_IP_MASK)) {
1562 oudph->check = ~csum_tcpudp_magic(oiph->saddr,
1563 oiph->daddr,
1564 (skb->len - skb_transport_offset(skb)),
1565 IPPROTO_UDP, 0);
1566 *cd_tunneling |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
1567 }
1568 } else {
1569 network_hdr_len = skb_network_header_len(skb);
1570 this_ip_hdr = ip_hdr(skb);
1571 this_ipv6_hdr = ipv6_hdr(skb);
1572 this_tcp_hdrlen = tcp_hdrlen(skb);
1573 }
1574
1575 /* Enable IP checksum offloads */
1576 if (*tx_flags & I40E_TX_FLAGS_IPV4) {
1577 l4_hdr = this_ip_hdr->protocol;
1578 /* the stack computes the IP header already, the only time we
1579 * need the hardware to recompute it is in the case of TSO.
1580 */
1581 if (*tx_flags & I40E_TX_FLAGS_TSO) {
1582 *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
1583 this_ip_hdr->check = 0;
1584 } else {
1585 *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
1586 }
1587 /* Now set the td_offset for IP header length */
1588 *td_offset = (network_hdr_len >> 2) <<
1589 I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1590 } else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
1591 l4_hdr = this_ipv6_hdr->nexthdr;
1592 *td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
1593 /* Now set the td_offset for IP header length */
1594 *td_offset = (network_hdr_len >> 2) <<
1595 I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1596 }
1597 /* words in MACLEN + dwords in IPLEN + dwords in L4Len */
1598 *td_offset |= (skb_network_offset(skb) >> 1) <<
1599 I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
1600
1601 /* Enable L4 checksum offloads */
1602 switch (l4_hdr) {
1603 case IPPROTO_TCP:
1604 /* enable checksum offloads */
1605 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
1606 *td_offset |= (this_tcp_hdrlen >> 2) <<
1607 I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1608 break;
1609 case IPPROTO_SCTP:
1610 /* enable SCTP checksum offload */
1611 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
1612 *td_offset |= (sizeof(struct sctphdr) >> 2) <<
1613 I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1614 break;
1615 case IPPROTO_UDP:
1616 /* enable UDP checksum offload */
1617 *td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
1618 *td_offset |= (sizeof(struct udphdr) >> 2) <<
1619 I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1620 break;
1621 default:
1622 break;
1623 }
1624 }
1625
1626 /**
1627 * i40e_create_tx_ctx Build the Tx context descriptor
1628 * @tx_ring: ring to create the descriptor on
1629 * @cd_type_cmd_tso_mss: Quad Word 1
1630 * @cd_tunneling: Quad Word 0 - bits 0-31
1631 * @cd_l2tag2: Quad Word 0 - bits 32-63
1632 **/
i40e_create_tx_ctx(struct i40e_ring * tx_ring,const u64 cd_type_cmd_tso_mss,const u32 cd_tunneling,const u32 cd_l2tag2)1633 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
1634 const u64 cd_type_cmd_tso_mss,
1635 const u32 cd_tunneling, const u32 cd_l2tag2)
1636 {
1637 struct i40e_tx_context_desc *context_desc;
1638 int i = tx_ring->next_to_use;
1639
1640 if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
1641 !cd_tunneling && !cd_l2tag2)
1642 return;
1643
1644 /* grab the next descriptor */
1645 context_desc = I40E_TX_CTXTDESC(tx_ring, i);
1646
1647 i++;
1648 tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1649
1650 /* cpu_to_le32 and assign to struct fields */
1651 context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
1652 context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
1653 context_desc->rsvd = cpu_to_le16(0);
1654 context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
1655 }
1656
1657 /**
1658 * i40e_chk_linearize - Check if there are more than 8 fragments per packet
1659 * @skb: send buffer
1660 * @tx_flags: collected send information
1661 *
1662 * Note: Our HW can't scatter-gather more than 8 fragments to build
1663 * a packet on the wire and so we need to figure out the cases where we
1664 * need to linearize the skb.
1665 **/
i40e_chk_linearize(struct sk_buff * skb,u32 tx_flags)1666 static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags)
1667 {
1668 struct skb_frag_struct *frag;
1669 bool linearize = false;
1670 unsigned int size = 0;
1671 u16 num_frags;
1672 u16 gso_segs;
1673
1674 num_frags = skb_shinfo(skb)->nr_frags;
1675 gso_segs = skb_shinfo(skb)->gso_segs;
1676
1677 if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO)) {
1678 u16 j = 0;
1679
1680 if (num_frags < (I40E_MAX_BUFFER_TXD))
1681 goto linearize_chk_done;
1682 /* try the simple math, if we have too many frags per segment */
1683 if (DIV_ROUND_UP((num_frags + gso_segs), gso_segs) >
1684 I40E_MAX_BUFFER_TXD) {
1685 linearize = true;
1686 goto linearize_chk_done;
1687 }
1688 frag = &skb_shinfo(skb)->frags[0];
1689 /* we might still have more fragments per segment */
1690 do {
1691 size += skb_frag_size(frag);
1692 frag++; j++;
1693 if ((size >= skb_shinfo(skb)->gso_size) &&
1694 (j < I40E_MAX_BUFFER_TXD)) {
1695 size = (size % skb_shinfo(skb)->gso_size);
1696 j = (size) ? 1 : 0;
1697 }
1698 if (j == I40E_MAX_BUFFER_TXD) {
1699 linearize = true;
1700 break;
1701 }
1702 num_frags--;
1703 } while (num_frags);
1704 } else {
1705 if (num_frags >= I40E_MAX_BUFFER_TXD)
1706 linearize = true;
1707 }
1708
1709 linearize_chk_done:
1710 return linearize;
1711 }
1712
1713 /**
1714 * __i40evf_maybe_stop_tx - 2nd level check for tx stop conditions
1715 * @tx_ring: the ring to be checked
1716 * @size: the size buffer we want to assure is available
1717 *
1718 * Returns -EBUSY if a stop is needed, else 0
1719 **/
__i40evf_maybe_stop_tx(struct i40e_ring * tx_ring,int size)1720 static inline int __i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
1721 {
1722 netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
1723 /* Memory barrier before checking head and tail */
1724 smp_mb();
1725
1726 /* Check again in a case another CPU has just made room available. */
1727 if (likely(I40E_DESC_UNUSED(tx_ring) < size))
1728 return -EBUSY;
1729
1730 /* A reprieve! - use start_queue because it doesn't call schedule */
1731 netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
1732 ++tx_ring->tx_stats.restart_queue;
1733 return 0;
1734 }
1735
1736 /**
1737 * i40evf_maybe_stop_tx - 1st level check for tx stop conditions
1738 * @tx_ring: the ring to be checked
1739 * @size: the size buffer we want to assure is available
1740 *
1741 * Returns 0 if stop is not needed
1742 **/
i40evf_maybe_stop_tx(struct i40e_ring * tx_ring,int size)1743 static inline int i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
1744 {
1745 if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
1746 return 0;
1747 return __i40evf_maybe_stop_tx(tx_ring, size);
1748 }
1749
1750 /**
1751 * i40evf_tx_map - Build the Tx descriptor
1752 * @tx_ring: ring to send buffer on
1753 * @skb: send buffer
1754 * @first: first buffer info buffer to use
1755 * @tx_flags: collected send information
1756 * @hdr_len: size of the packet header
1757 * @td_cmd: the command field in the descriptor
1758 * @td_offset: offset for checksum or crc
1759 **/
i40evf_tx_map(struct i40e_ring * tx_ring,struct sk_buff * skb,struct i40e_tx_buffer * first,u32 tx_flags,const u8 hdr_len,u32 td_cmd,u32 td_offset)1760 static inline void i40evf_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
1761 struct i40e_tx_buffer *first, u32 tx_flags,
1762 const u8 hdr_len, u32 td_cmd, u32 td_offset)
1763 {
1764 unsigned int data_len = skb->data_len;
1765 unsigned int size = skb_headlen(skb);
1766 struct skb_frag_struct *frag;
1767 struct i40e_tx_buffer *tx_bi;
1768 struct i40e_tx_desc *tx_desc;
1769 u16 i = tx_ring->next_to_use;
1770 u32 td_tag = 0;
1771 dma_addr_t dma;
1772 u16 gso_segs;
1773
1774 if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
1775 td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
1776 td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
1777 I40E_TX_FLAGS_VLAN_SHIFT;
1778 }
1779
1780 if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
1781 gso_segs = skb_shinfo(skb)->gso_segs;
1782 else
1783 gso_segs = 1;
1784
1785 /* multiply data chunks by size of headers */
1786 first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
1787 first->gso_segs = gso_segs;
1788 first->skb = skb;
1789 first->tx_flags = tx_flags;
1790
1791 dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1792
1793 tx_desc = I40E_TX_DESC(tx_ring, i);
1794 tx_bi = first;
1795
1796 for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1797 if (dma_mapping_error(tx_ring->dev, dma))
1798 goto dma_error;
1799
1800 /* record length, and DMA address */
1801 dma_unmap_len_set(tx_bi, len, size);
1802 dma_unmap_addr_set(tx_bi, dma, dma);
1803
1804 tx_desc->buffer_addr = cpu_to_le64(dma);
1805
1806 while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
1807 tx_desc->cmd_type_offset_bsz =
1808 build_ctob(td_cmd, td_offset,
1809 I40E_MAX_DATA_PER_TXD, td_tag);
1810
1811 tx_desc++;
1812 i++;
1813 if (i == tx_ring->count) {
1814 tx_desc = I40E_TX_DESC(tx_ring, 0);
1815 i = 0;
1816 }
1817
1818 dma += I40E_MAX_DATA_PER_TXD;
1819 size -= I40E_MAX_DATA_PER_TXD;
1820
1821 tx_desc->buffer_addr = cpu_to_le64(dma);
1822 }
1823
1824 if (likely(!data_len))
1825 break;
1826
1827 tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
1828 size, td_tag);
1829
1830 tx_desc++;
1831 i++;
1832 if (i == tx_ring->count) {
1833 tx_desc = I40E_TX_DESC(tx_ring, 0);
1834 i = 0;
1835 }
1836
1837 size = skb_frag_size(frag);
1838 data_len -= size;
1839
1840 dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1841 DMA_TO_DEVICE);
1842
1843 tx_bi = &tx_ring->tx_bi[i];
1844 }
1845
1846 /* Place RS bit on last descriptor of any packet that spans across the
1847 * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
1848 */
1849 #define WB_STRIDE 0x3
1850 if (((i & WB_STRIDE) != WB_STRIDE) &&
1851 (first <= &tx_ring->tx_bi[i]) &&
1852 (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
1853 tx_desc->cmd_type_offset_bsz =
1854 build_ctob(td_cmd, td_offset, size, td_tag) |
1855 cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
1856 I40E_TXD_QW1_CMD_SHIFT);
1857 } else {
1858 tx_desc->cmd_type_offset_bsz =
1859 build_ctob(td_cmd, td_offset, size, td_tag) |
1860 cpu_to_le64((u64)I40E_TXD_CMD <<
1861 I40E_TXD_QW1_CMD_SHIFT);
1862 }
1863
1864 netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
1865 tx_ring->queue_index),
1866 first->bytecount);
1867
1868 /* Force memory writes to complete before letting h/w
1869 * know there are new descriptors to fetch. (Only
1870 * applicable for weak-ordered memory model archs,
1871 * such as IA-64).
1872 */
1873 wmb();
1874
1875 /* set next_to_watch value indicating a packet is present */
1876 first->next_to_watch = tx_desc;
1877
1878 i++;
1879 if (i == tx_ring->count)
1880 i = 0;
1881
1882 tx_ring->next_to_use = i;
1883
1884 i40evf_maybe_stop_tx(tx_ring, DESC_NEEDED);
1885 /* notify HW of packet */
1886 if (!skb->xmit_more ||
1887 netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
1888 tx_ring->queue_index)))
1889 writel(i, tx_ring->tail);
1890 else
1891 prefetchw(tx_desc + 1);
1892
1893 return;
1894
1895 dma_error:
1896 dev_info(tx_ring->dev, "TX DMA map failed\n");
1897
1898 /* clear dma mappings for failed tx_bi map */
1899 for (;;) {
1900 tx_bi = &tx_ring->tx_bi[i];
1901 i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
1902 if (tx_bi == first)
1903 break;
1904 if (i == 0)
1905 i = tx_ring->count;
1906 i--;
1907 }
1908
1909 tx_ring->next_to_use = i;
1910 }
1911
1912 /**
1913 * i40evf_xmit_descriptor_count - calculate number of tx descriptors needed
1914 * @skb: send buffer
1915 * @tx_ring: ring to send buffer on
1916 *
1917 * Returns number of data descriptors needed for this skb. Returns 0 to indicate
1918 * there is not enough descriptors available in this ring since we need at least
1919 * one descriptor.
1920 **/
i40evf_xmit_descriptor_count(struct sk_buff * skb,struct i40e_ring * tx_ring)1921 static inline int i40evf_xmit_descriptor_count(struct sk_buff *skb,
1922 struct i40e_ring *tx_ring)
1923 {
1924 unsigned int f;
1925 int count = 0;
1926
1927 /* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
1928 * + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
1929 * + 4 desc gap to avoid the cache line where head is,
1930 * + 1 desc for context descriptor,
1931 * otherwise try next time
1932 */
1933 for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
1934 count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
1935
1936 count += TXD_USE_COUNT(skb_headlen(skb));
1937 if (i40evf_maybe_stop_tx(tx_ring, count + 4 + 1)) {
1938 tx_ring->tx_stats.tx_busy++;
1939 return 0;
1940 }
1941 return count;
1942 }
1943
1944 /**
1945 * i40e_xmit_frame_ring - Sends buffer on Tx ring
1946 * @skb: send buffer
1947 * @tx_ring: ring to send buffer on
1948 *
1949 * Returns NETDEV_TX_OK if sent, else an error code
1950 **/
i40e_xmit_frame_ring(struct sk_buff * skb,struct i40e_ring * tx_ring)1951 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
1952 struct i40e_ring *tx_ring)
1953 {
1954 u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
1955 u32 cd_tunneling = 0, cd_l2tag2 = 0;
1956 struct i40e_tx_buffer *first;
1957 u32 td_offset = 0;
1958 u32 tx_flags = 0;
1959 __be16 protocol;
1960 u32 td_cmd = 0;
1961 u8 hdr_len = 0;
1962 int tso;
1963
1964 if (0 == i40evf_xmit_descriptor_count(skb, tx_ring))
1965 return NETDEV_TX_BUSY;
1966
1967 /* prepare the xmit flags */
1968 if (i40evf_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
1969 goto out_drop;
1970
1971 /* obtain protocol of skb */
1972 protocol = vlan_get_protocol(skb);
1973
1974 /* record the location of the first descriptor for this packet */
1975 first = &tx_ring->tx_bi[tx_ring->next_to_use];
1976
1977 /* setup IPv4/IPv6 offloads */
1978 if (protocol == htons(ETH_P_IP))
1979 tx_flags |= I40E_TX_FLAGS_IPV4;
1980 else if (protocol == htons(ETH_P_IPV6))
1981 tx_flags |= I40E_TX_FLAGS_IPV6;
1982
1983 tso = i40e_tso(tx_ring, skb, &hdr_len,
1984 &cd_type_cmd_tso_mss, &cd_tunneling);
1985
1986 if (tso < 0)
1987 goto out_drop;
1988 else if (tso)
1989 tx_flags |= I40E_TX_FLAGS_TSO;
1990
1991 if (i40e_chk_linearize(skb, tx_flags)) {
1992 if (skb_linearize(skb))
1993 goto out_drop;
1994 tx_ring->tx_stats.tx_linearize++;
1995 }
1996 skb_tx_timestamp(skb);
1997
1998 /* always enable CRC insertion offload */
1999 td_cmd |= I40E_TX_DESC_CMD_ICRC;
2000
2001 /* Always offload the checksum, since it's in the data descriptor */
2002 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2003 tx_flags |= I40E_TX_FLAGS_CSUM;
2004
2005 i40e_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset,
2006 tx_ring, &cd_tunneling);
2007 }
2008
2009 i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
2010 cd_tunneling, cd_l2tag2);
2011
2012 i40evf_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
2013 td_cmd, td_offset);
2014
2015 return NETDEV_TX_OK;
2016
2017 out_drop:
2018 dev_kfree_skb_any(skb);
2019 return NETDEV_TX_OK;
2020 }
2021
2022 /**
2023 * i40evf_xmit_frame - Selects the correct VSI and Tx queue to send buffer
2024 * @skb: send buffer
2025 * @netdev: network interface device structure
2026 *
2027 * Returns NETDEV_TX_OK if sent, else an error code
2028 **/
i40evf_xmit_frame(struct sk_buff * skb,struct net_device * netdev)2029 netdev_tx_t i40evf_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
2030 {
2031 struct i40evf_adapter *adapter = netdev_priv(netdev);
2032 struct i40e_ring *tx_ring = adapter->tx_rings[skb->queue_mapping];
2033
2034 /* hardware can't handle really short frames, hardware padding works
2035 * beyond this point
2036 */
2037 if (unlikely(skb->len < I40E_MIN_TX_LEN)) {
2038 if (skb_pad(skb, I40E_MIN_TX_LEN - skb->len))
2039 return NETDEV_TX_OK;
2040 skb->len = I40E_MIN_TX_LEN;
2041 skb_set_tail_pointer(skb, I40E_MIN_TX_LEN);
2042 }
2043
2044 return i40e_xmit_frame_ring(skb, tx_ring);
2045 }
2046