1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2018, Intel Corporation. */
3
4 /* The driver transmit and receive code */
5
6 #include <linux/prefetch.h>
7 #include <linux/mm.h>
8 #include <linux/bpf_trace.h>
9 #include <net/xdp.h>
10 #include "ice_txrx_lib.h"
11 #include "ice_lib.h"
12 #include "ice.h"
13 #include "ice_dcb_lib.h"
14 #include "ice_xsk.h"
15
16 #define ICE_RX_HDR_SIZE 256
17
18 #define FDIR_DESC_RXDID 0x40
19 #define ICE_FDIR_CLEAN_DELAY 10
20
21 /**
22 * ice_prgm_fdir_fltr - Program a Flow Director filter
23 * @vsi: VSI to send dummy packet
24 * @fdir_desc: flow director descriptor
25 * @raw_packet: allocated buffer for flow director
26 */
27 int
ice_prgm_fdir_fltr(struct ice_vsi * vsi,struct ice_fltr_desc * fdir_desc,u8 * raw_packet)28 ice_prgm_fdir_fltr(struct ice_vsi *vsi, struct ice_fltr_desc *fdir_desc,
29 u8 *raw_packet)
30 {
31 struct ice_tx_buf *tx_buf, *first;
32 struct ice_fltr_desc *f_desc;
33 struct ice_tx_desc *tx_desc;
34 struct ice_ring *tx_ring;
35 struct device *dev;
36 dma_addr_t dma;
37 u32 td_cmd;
38 u16 i;
39
40 /* VSI and Tx ring */
41 if (!vsi)
42 return -ENOENT;
43 tx_ring = vsi->tx_rings[0];
44 if (!tx_ring || !tx_ring->desc)
45 return -ENOENT;
46 dev = tx_ring->dev;
47
48 /* we are using two descriptors to add/del a filter and we can wait */
49 for (i = ICE_FDIR_CLEAN_DELAY; ICE_DESC_UNUSED(tx_ring) < 2; i--) {
50 if (!i)
51 return -EAGAIN;
52 msleep_interruptible(1);
53 }
54
55 dma = dma_map_single(dev, raw_packet, ICE_FDIR_MAX_RAW_PKT_SIZE,
56 DMA_TO_DEVICE);
57
58 if (dma_mapping_error(dev, dma))
59 return -EINVAL;
60
61 /* grab the next descriptor */
62 i = tx_ring->next_to_use;
63 first = &tx_ring->tx_buf[i];
64 f_desc = ICE_TX_FDIRDESC(tx_ring, i);
65 memcpy(f_desc, fdir_desc, sizeof(*f_desc));
66
67 i++;
68 i = (i < tx_ring->count) ? i : 0;
69 tx_desc = ICE_TX_DESC(tx_ring, i);
70 tx_buf = &tx_ring->tx_buf[i];
71
72 i++;
73 tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
74
75 memset(tx_buf, 0, sizeof(*tx_buf));
76 dma_unmap_len_set(tx_buf, len, ICE_FDIR_MAX_RAW_PKT_SIZE);
77 dma_unmap_addr_set(tx_buf, dma, dma);
78
79 tx_desc->buf_addr = cpu_to_le64(dma);
80 td_cmd = ICE_TXD_LAST_DESC_CMD | ICE_TX_DESC_CMD_DUMMY |
81 ICE_TX_DESC_CMD_RE;
82
83 tx_buf->tx_flags = ICE_TX_FLAGS_DUMMY_PKT;
84 tx_buf->raw_buf = raw_packet;
85
86 tx_desc->cmd_type_offset_bsz =
87 ice_build_ctob(td_cmd, 0, ICE_FDIR_MAX_RAW_PKT_SIZE, 0);
88
89 /* Force memory write to complete before letting h/w know
90 * there are new descriptors to fetch.
91 */
92 wmb();
93
94 /* mark the data descriptor to be watched */
95 first->next_to_watch = tx_desc;
96
97 writel(tx_ring->next_to_use, tx_ring->tail);
98
99 return 0;
100 }
101
102 /**
103 * ice_unmap_and_free_tx_buf - Release a Tx buffer
104 * @ring: the ring that owns the buffer
105 * @tx_buf: the buffer to free
106 */
107 static void
ice_unmap_and_free_tx_buf(struct ice_ring * ring,struct ice_tx_buf * tx_buf)108 ice_unmap_and_free_tx_buf(struct ice_ring *ring, struct ice_tx_buf *tx_buf)
109 {
110 if (tx_buf->skb) {
111 if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
112 devm_kfree(ring->dev, tx_buf->raw_buf);
113 else if (ice_ring_is_xdp(ring))
114 page_frag_free(tx_buf->raw_buf);
115 else
116 dev_kfree_skb_any(tx_buf->skb);
117 if (dma_unmap_len(tx_buf, len))
118 dma_unmap_single(ring->dev,
119 dma_unmap_addr(tx_buf, dma),
120 dma_unmap_len(tx_buf, len),
121 DMA_TO_DEVICE);
122 } else if (dma_unmap_len(tx_buf, len)) {
123 dma_unmap_page(ring->dev,
124 dma_unmap_addr(tx_buf, dma),
125 dma_unmap_len(tx_buf, len),
126 DMA_TO_DEVICE);
127 }
128
129 tx_buf->next_to_watch = NULL;
130 tx_buf->skb = NULL;
131 dma_unmap_len_set(tx_buf, len, 0);
132 /* tx_buf must be completely set up in the transmit path */
133 }
134
txring_txq(const struct ice_ring * ring)135 static struct netdev_queue *txring_txq(const struct ice_ring *ring)
136 {
137 return netdev_get_tx_queue(ring->netdev, ring->q_index);
138 }
139
140 /**
141 * ice_clean_tx_ring - Free any empty Tx buffers
142 * @tx_ring: ring to be cleaned
143 */
ice_clean_tx_ring(struct ice_ring * tx_ring)144 void ice_clean_tx_ring(struct ice_ring *tx_ring)
145 {
146 u16 i;
147
148 if (ice_ring_is_xdp(tx_ring) && tx_ring->xsk_pool) {
149 ice_xsk_clean_xdp_ring(tx_ring);
150 goto tx_skip_free;
151 }
152
153 /* ring already cleared, nothing to do */
154 if (!tx_ring->tx_buf)
155 return;
156
157 /* Free all the Tx ring sk_buffs */
158 for (i = 0; i < tx_ring->count; i++)
159 ice_unmap_and_free_tx_buf(tx_ring, &tx_ring->tx_buf[i]);
160
161 tx_skip_free:
162 memset(tx_ring->tx_buf, 0, sizeof(*tx_ring->tx_buf) * tx_ring->count);
163
164 /* Zero out the descriptor ring */
165 memset(tx_ring->desc, 0, tx_ring->size);
166
167 tx_ring->next_to_use = 0;
168 tx_ring->next_to_clean = 0;
169
170 if (!tx_ring->netdev)
171 return;
172
173 /* cleanup Tx queue statistics */
174 netdev_tx_reset_queue(txring_txq(tx_ring));
175 }
176
177 /**
178 * ice_free_tx_ring - Free Tx resources per queue
179 * @tx_ring: Tx descriptor ring for a specific queue
180 *
181 * Free all transmit software resources
182 */
ice_free_tx_ring(struct ice_ring * tx_ring)183 void ice_free_tx_ring(struct ice_ring *tx_ring)
184 {
185 ice_clean_tx_ring(tx_ring);
186 devm_kfree(tx_ring->dev, tx_ring->tx_buf);
187 tx_ring->tx_buf = NULL;
188
189 if (tx_ring->desc) {
190 dmam_free_coherent(tx_ring->dev, tx_ring->size,
191 tx_ring->desc, tx_ring->dma);
192 tx_ring->desc = NULL;
193 }
194 }
195
196 /**
197 * ice_clean_tx_irq - Reclaim resources after transmit completes
198 * @tx_ring: Tx ring to clean
199 * @napi_budget: Used to determine if we are in netpoll
200 *
201 * Returns true if there's any budget left (e.g. the clean is finished)
202 */
ice_clean_tx_irq(struct ice_ring * tx_ring,int napi_budget)203 static bool ice_clean_tx_irq(struct ice_ring *tx_ring, int napi_budget)
204 {
205 unsigned int total_bytes = 0, total_pkts = 0;
206 unsigned int budget = ICE_DFLT_IRQ_WORK;
207 struct ice_vsi *vsi = tx_ring->vsi;
208 s16 i = tx_ring->next_to_clean;
209 struct ice_tx_desc *tx_desc;
210 struct ice_tx_buf *tx_buf;
211
212 tx_buf = &tx_ring->tx_buf[i];
213 tx_desc = ICE_TX_DESC(tx_ring, i);
214 i -= tx_ring->count;
215
216 prefetch(&vsi->state);
217
218 do {
219 struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
220
221 /* if next_to_watch is not set then there is no work pending */
222 if (!eop_desc)
223 break;
224
225 smp_rmb(); /* prevent any other reads prior to eop_desc */
226
227 /* if the descriptor isn't done, no work yet to do */
228 if (!(eop_desc->cmd_type_offset_bsz &
229 cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
230 break;
231
232 /* clear next_to_watch to prevent false hangs */
233 tx_buf->next_to_watch = NULL;
234
235 /* update the statistics for this packet */
236 total_bytes += tx_buf->bytecount;
237 total_pkts += tx_buf->gso_segs;
238
239 if (ice_ring_is_xdp(tx_ring))
240 page_frag_free(tx_buf->raw_buf);
241 else
242 /* free the skb */
243 napi_consume_skb(tx_buf->skb, napi_budget);
244
245 /* unmap skb header data */
246 dma_unmap_single(tx_ring->dev,
247 dma_unmap_addr(tx_buf, dma),
248 dma_unmap_len(tx_buf, len),
249 DMA_TO_DEVICE);
250
251 /* clear tx_buf data */
252 tx_buf->skb = NULL;
253 dma_unmap_len_set(tx_buf, len, 0);
254
255 /* unmap remaining buffers */
256 while (tx_desc != eop_desc) {
257 tx_buf++;
258 tx_desc++;
259 i++;
260 if (unlikely(!i)) {
261 i -= tx_ring->count;
262 tx_buf = tx_ring->tx_buf;
263 tx_desc = ICE_TX_DESC(tx_ring, 0);
264 }
265
266 /* unmap any remaining paged data */
267 if (dma_unmap_len(tx_buf, len)) {
268 dma_unmap_page(tx_ring->dev,
269 dma_unmap_addr(tx_buf, dma),
270 dma_unmap_len(tx_buf, len),
271 DMA_TO_DEVICE);
272 dma_unmap_len_set(tx_buf, len, 0);
273 }
274 }
275
276 /* move us one more past the eop_desc for start of next pkt */
277 tx_buf++;
278 tx_desc++;
279 i++;
280 if (unlikely(!i)) {
281 i -= tx_ring->count;
282 tx_buf = tx_ring->tx_buf;
283 tx_desc = ICE_TX_DESC(tx_ring, 0);
284 }
285
286 prefetch(tx_desc);
287
288 /* update budget accounting */
289 budget--;
290 } while (likely(budget));
291
292 i += tx_ring->count;
293 tx_ring->next_to_clean = i;
294
295 ice_update_tx_ring_stats(tx_ring, total_pkts, total_bytes);
296
297 if (ice_ring_is_xdp(tx_ring))
298 return !!budget;
299
300 netdev_tx_completed_queue(txring_txq(tx_ring), total_pkts,
301 total_bytes);
302
303 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
304 if (unlikely(total_pkts && netif_carrier_ok(tx_ring->netdev) &&
305 (ICE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
306 /* Make sure that anybody stopping the queue after this
307 * sees the new next_to_clean.
308 */
309 smp_mb();
310 if (__netif_subqueue_stopped(tx_ring->netdev,
311 tx_ring->q_index) &&
312 !test_bit(__ICE_DOWN, vsi->state)) {
313 netif_wake_subqueue(tx_ring->netdev,
314 tx_ring->q_index);
315 ++tx_ring->tx_stats.restart_q;
316 }
317 }
318
319 return !!budget;
320 }
321
322 /**
323 * ice_setup_tx_ring - Allocate the Tx descriptors
324 * @tx_ring: the Tx ring to set up
325 *
326 * Return 0 on success, negative on error
327 */
ice_setup_tx_ring(struct ice_ring * tx_ring)328 int ice_setup_tx_ring(struct ice_ring *tx_ring)
329 {
330 struct device *dev = tx_ring->dev;
331
332 if (!dev)
333 return -ENOMEM;
334
335 /* warn if we are about to overwrite the pointer */
336 WARN_ON(tx_ring->tx_buf);
337 tx_ring->tx_buf =
338 devm_kzalloc(dev, sizeof(*tx_ring->tx_buf) * tx_ring->count,
339 GFP_KERNEL);
340 if (!tx_ring->tx_buf)
341 return -ENOMEM;
342
343 /* round up to nearest page */
344 tx_ring->size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
345 PAGE_SIZE);
346 tx_ring->desc = dmam_alloc_coherent(dev, tx_ring->size, &tx_ring->dma,
347 GFP_KERNEL);
348 if (!tx_ring->desc) {
349 dev_err(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
350 tx_ring->size);
351 goto err;
352 }
353
354 tx_ring->next_to_use = 0;
355 tx_ring->next_to_clean = 0;
356 tx_ring->tx_stats.prev_pkt = -1;
357 return 0;
358
359 err:
360 devm_kfree(dev, tx_ring->tx_buf);
361 tx_ring->tx_buf = NULL;
362 return -ENOMEM;
363 }
364
365 /**
366 * ice_clean_rx_ring - Free Rx buffers
367 * @rx_ring: ring to be cleaned
368 */
ice_clean_rx_ring(struct ice_ring * rx_ring)369 void ice_clean_rx_ring(struct ice_ring *rx_ring)
370 {
371 struct device *dev = rx_ring->dev;
372 u16 i;
373
374 /* ring already cleared, nothing to do */
375 if (!rx_ring->rx_buf)
376 return;
377
378 if (rx_ring->xsk_pool) {
379 ice_xsk_clean_rx_ring(rx_ring);
380 goto rx_skip_free;
381 }
382
383 /* Free all the Rx ring sk_buffs */
384 for (i = 0; i < rx_ring->count; i++) {
385 struct ice_rx_buf *rx_buf = &rx_ring->rx_buf[i];
386
387 if (rx_buf->skb) {
388 dev_kfree_skb(rx_buf->skb);
389 rx_buf->skb = NULL;
390 }
391 if (!rx_buf->page)
392 continue;
393
394 /* Invalidate cache lines that may have been written to by
395 * device so that we avoid corrupting memory.
396 */
397 dma_sync_single_range_for_cpu(dev, rx_buf->dma,
398 rx_buf->page_offset,
399 rx_ring->rx_buf_len,
400 DMA_FROM_DEVICE);
401
402 /* free resources associated with mapping */
403 dma_unmap_page_attrs(dev, rx_buf->dma, ice_rx_pg_size(rx_ring),
404 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
405 __page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
406
407 rx_buf->page = NULL;
408 rx_buf->page_offset = 0;
409 }
410
411 rx_skip_free:
412 memset(rx_ring->rx_buf, 0, sizeof(*rx_ring->rx_buf) * rx_ring->count);
413
414 /* Zero out the descriptor ring */
415 memset(rx_ring->desc, 0, rx_ring->size);
416
417 rx_ring->next_to_alloc = 0;
418 rx_ring->next_to_clean = 0;
419 rx_ring->next_to_use = 0;
420 }
421
422 /**
423 * ice_free_rx_ring - Free Rx resources
424 * @rx_ring: ring to clean the resources from
425 *
426 * Free all receive software resources
427 */
ice_free_rx_ring(struct ice_ring * rx_ring)428 void ice_free_rx_ring(struct ice_ring *rx_ring)
429 {
430 ice_clean_rx_ring(rx_ring);
431 if (rx_ring->vsi->type == ICE_VSI_PF)
432 if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
433 xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
434 rx_ring->xdp_prog = NULL;
435 devm_kfree(rx_ring->dev, rx_ring->rx_buf);
436 rx_ring->rx_buf = NULL;
437
438 if (rx_ring->desc) {
439 dmam_free_coherent(rx_ring->dev, rx_ring->size,
440 rx_ring->desc, rx_ring->dma);
441 rx_ring->desc = NULL;
442 }
443 }
444
445 /**
446 * ice_setup_rx_ring - Allocate the Rx descriptors
447 * @rx_ring: the Rx ring to set up
448 *
449 * Return 0 on success, negative on error
450 */
ice_setup_rx_ring(struct ice_ring * rx_ring)451 int ice_setup_rx_ring(struct ice_ring *rx_ring)
452 {
453 struct device *dev = rx_ring->dev;
454
455 if (!dev)
456 return -ENOMEM;
457
458 /* warn if we are about to overwrite the pointer */
459 WARN_ON(rx_ring->rx_buf);
460 rx_ring->rx_buf =
461 devm_kzalloc(dev, sizeof(*rx_ring->rx_buf) * rx_ring->count,
462 GFP_KERNEL);
463 if (!rx_ring->rx_buf)
464 return -ENOMEM;
465
466 /* round up to nearest page */
467 rx_ring->size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
468 PAGE_SIZE);
469 rx_ring->desc = dmam_alloc_coherent(dev, rx_ring->size, &rx_ring->dma,
470 GFP_KERNEL);
471 if (!rx_ring->desc) {
472 dev_err(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
473 rx_ring->size);
474 goto err;
475 }
476
477 rx_ring->next_to_use = 0;
478 rx_ring->next_to_clean = 0;
479
480 if (ice_is_xdp_ena_vsi(rx_ring->vsi))
481 WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
482
483 if (rx_ring->vsi->type == ICE_VSI_PF &&
484 !xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
485 if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
486 rx_ring->q_index))
487 goto err;
488 return 0;
489
490 err:
491 devm_kfree(dev, rx_ring->rx_buf);
492 rx_ring->rx_buf = NULL;
493 return -ENOMEM;
494 }
495
496 /**
497 * ice_rx_offset - Return expected offset into page to access data
498 * @rx_ring: Ring we are requesting offset of
499 *
500 * Returns the offset value for ring into the data buffer.
501 */
ice_rx_offset(struct ice_ring * rx_ring)502 static unsigned int ice_rx_offset(struct ice_ring *rx_ring)
503 {
504 if (ice_ring_uses_build_skb(rx_ring))
505 return ICE_SKB_PAD;
506 else if (ice_is_xdp_ena_vsi(rx_ring->vsi))
507 return XDP_PACKET_HEADROOM;
508
509 return 0;
510 }
511
512 static unsigned int
ice_rx_frame_truesize(struct ice_ring * rx_ring,unsigned int __maybe_unused size)513 ice_rx_frame_truesize(struct ice_ring *rx_ring, unsigned int __maybe_unused size)
514 {
515 unsigned int truesize;
516
517 #if (PAGE_SIZE < 8192)
518 truesize = ice_rx_pg_size(rx_ring) / 2; /* Must be power-of-2 */
519 #else
520 truesize = ice_rx_offset(rx_ring) ?
521 SKB_DATA_ALIGN(ice_rx_offset(rx_ring) + size) +
522 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
523 SKB_DATA_ALIGN(size);
524 #endif
525 return truesize;
526 }
527
528 /**
529 * ice_run_xdp - Executes an XDP program on initialized xdp_buff
530 * @rx_ring: Rx ring
531 * @xdp: xdp_buff used as input to the XDP program
532 * @xdp_prog: XDP program to run
533 *
534 * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
535 */
536 static int
ice_run_xdp(struct ice_ring * rx_ring,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)537 ice_run_xdp(struct ice_ring *rx_ring, struct xdp_buff *xdp,
538 struct bpf_prog *xdp_prog)
539 {
540 struct ice_ring *xdp_ring;
541 int err, result;
542 u32 act;
543
544 act = bpf_prog_run_xdp(xdp_prog, xdp);
545 switch (act) {
546 case XDP_PASS:
547 return ICE_XDP_PASS;
548 case XDP_TX:
549 xdp_ring = rx_ring->vsi->xdp_rings[smp_processor_id()];
550 result = ice_xmit_xdp_buff(xdp, xdp_ring);
551 if (result == ICE_XDP_CONSUMED)
552 goto out_failure;
553 return result;
554 case XDP_REDIRECT:
555 err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
556 if (err)
557 goto out_failure;
558 return ICE_XDP_REDIR;
559 default:
560 bpf_warn_invalid_xdp_action(act);
561 fallthrough;
562 case XDP_ABORTED:
563 out_failure:
564 trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
565 fallthrough;
566 case XDP_DROP:
567 return ICE_XDP_CONSUMED;
568 }
569 }
570
571 /**
572 * ice_xdp_xmit - submit packets to XDP ring for transmission
573 * @dev: netdev
574 * @n: number of XDP frames to be transmitted
575 * @frames: XDP frames to be transmitted
576 * @flags: transmit flags
577 *
578 * Returns number of frames successfully sent. Frames that fail are
579 * free'ed via XDP return API.
580 * For error cases, a negative errno code is returned and no-frames
581 * are transmitted (caller must handle freeing frames).
582 */
583 int
ice_xdp_xmit(struct net_device * dev,int n,struct xdp_frame ** frames,u32 flags)584 ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
585 u32 flags)
586 {
587 struct ice_netdev_priv *np = netdev_priv(dev);
588 unsigned int queue_index = smp_processor_id();
589 struct ice_vsi *vsi = np->vsi;
590 struct ice_ring *xdp_ring;
591 int drops = 0, i;
592
593 if (test_bit(__ICE_DOWN, vsi->state))
594 return -ENETDOWN;
595
596 if (!ice_is_xdp_ena_vsi(vsi) || queue_index >= vsi->num_xdp_txq)
597 return -ENXIO;
598
599 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
600 return -EINVAL;
601
602 xdp_ring = vsi->xdp_rings[queue_index];
603 for (i = 0; i < n; i++) {
604 struct xdp_frame *xdpf = frames[i];
605 int err;
606
607 err = ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
608 if (err != ICE_XDP_TX) {
609 xdp_return_frame_rx_napi(xdpf);
610 drops++;
611 }
612 }
613
614 if (unlikely(flags & XDP_XMIT_FLUSH))
615 ice_xdp_ring_update_tail(xdp_ring);
616
617 return n - drops;
618 }
619
620 /**
621 * ice_alloc_mapped_page - recycle or make a new page
622 * @rx_ring: ring to use
623 * @bi: rx_buf struct to modify
624 *
625 * Returns true if the page was successfully allocated or
626 * reused.
627 */
628 static bool
ice_alloc_mapped_page(struct ice_ring * rx_ring,struct ice_rx_buf * bi)629 ice_alloc_mapped_page(struct ice_ring *rx_ring, struct ice_rx_buf *bi)
630 {
631 struct page *page = bi->page;
632 dma_addr_t dma;
633
634 /* since we are recycling buffers we should seldom need to alloc */
635 if (likely(page))
636 return true;
637
638 /* alloc new page for storage */
639 page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
640 if (unlikely(!page)) {
641 rx_ring->rx_stats.alloc_page_failed++;
642 return false;
643 }
644
645 /* map page for use */
646 dma = dma_map_page_attrs(rx_ring->dev, page, 0, ice_rx_pg_size(rx_ring),
647 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
648
649 /* if mapping failed free memory back to system since
650 * there isn't much point in holding memory we can't use
651 */
652 if (dma_mapping_error(rx_ring->dev, dma)) {
653 __free_pages(page, ice_rx_pg_order(rx_ring));
654 rx_ring->rx_stats.alloc_page_failed++;
655 return false;
656 }
657
658 bi->dma = dma;
659 bi->page = page;
660 bi->page_offset = ice_rx_offset(rx_ring);
661 page_ref_add(page, USHRT_MAX - 1);
662 bi->pagecnt_bias = USHRT_MAX;
663
664 return true;
665 }
666
667 /**
668 * ice_alloc_rx_bufs - Replace used receive buffers
669 * @rx_ring: ring to place buffers on
670 * @cleaned_count: number of buffers to replace
671 *
672 * Returns false if all allocations were successful, true if any fail. Returning
673 * true signals to the caller that we didn't replace cleaned_count buffers and
674 * there is more work to do.
675 *
676 * First, try to clean "cleaned_count" Rx buffers. Then refill the cleaned Rx
677 * buffers. Then bump tail at most one time. Grouping like this lets us avoid
678 * multiple tail writes per call.
679 */
ice_alloc_rx_bufs(struct ice_ring * rx_ring,u16 cleaned_count)680 bool ice_alloc_rx_bufs(struct ice_ring *rx_ring, u16 cleaned_count)
681 {
682 union ice_32b_rx_flex_desc *rx_desc;
683 u16 ntu = rx_ring->next_to_use;
684 struct ice_rx_buf *bi;
685
686 /* do nothing if no valid netdev defined */
687 if ((!rx_ring->netdev && rx_ring->vsi->type != ICE_VSI_CTRL) ||
688 !cleaned_count)
689 return false;
690
691 /* get the Rx descriptor and buffer based on next_to_use */
692 rx_desc = ICE_RX_DESC(rx_ring, ntu);
693 bi = &rx_ring->rx_buf[ntu];
694
695 do {
696 /* if we fail here, we have work remaining */
697 if (!ice_alloc_mapped_page(rx_ring, bi))
698 break;
699
700 /* sync the buffer for use by the device */
701 dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
702 bi->page_offset,
703 rx_ring->rx_buf_len,
704 DMA_FROM_DEVICE);
705
706 /* Refresh the desc even if buffer_addrs didn't change
707 * because each write-back erases this info.
708 */
709 rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
710
711 rx_desc++;
712 bi++;
713 ntu++;
714 if (unlikely(ntu == rx_ring->count)) {
715 rx_desc = ICE_RX_DESC(rx_ring, 0);
716 bi = rx_ring->rx_buf;
717 ntu = 0;
718 }
719
720 /* clear the status bits for the next_to_use descriptor */
721 rx_desc->wb.status_error0 = 0;
722
723 cleaned_count--;
724 } while (cleaned_count);
725
726 if (rx_ring->next_to_use != ntu)
727 ice_release_rx_desc(rx_ring, ntu);
728
729 return !!cleaned_count;
730 }
731
732 /**
733 * ice_page_is_reserved - check if reuse is possible
734 * @page: page struct to check
735 */
ice_page_is_reserved(struct page * page)736 static bool ice_page_is_reserved(struct page *page)
737 {
738 return (page_to_nid(page) != numa_mem_id()) || page_is_pfmemalloc(page);
739 }
740
741 /**
742 * ice_rx_buf_adjust_pg_offset - Prepare Rx buffer for reuse
743 * @rx_buf: Rx buffer to adjust
744 * @size: Size of adjustment
745 *
746 * Update the offset within page so that Rx buf will be ready to be reused.
747 * For systems with PAGE_SIZE < 8192 this function will flip the page offset
748 * so the second half of page assigned to Rx buffer will be used, otherwise
749 * the offset is moved by "size" bytes
750 */
751 static void
ice_rx_buf_adjust_pg_offset(struct ice_rx_buf * rx_buf,unsigned int size)752 ice_rx_buf_adjust_pg_offset(struct ice_rx_buf *rx_buf, unsigned int size)
753 {
754 #if (PAGE_SIZE < 8192)
755 /* flip page offset to other buffer */
756 rx_buf->page_offset ^= size;
757 #else
758 /* move offset up to the next cache line */
759 rx_buf->page_offset += size;
760 #endif
761 }
762
763 /**
764 * ice_can_reuse_rx_page - Determine if page can be reused for another Rx
765 * @rx_buf: buffer containing the page
766 * @rx_buf_pgcnt: rx_buf page refcount pre xdp_do_redirect() call
767 *
768 * If page is reusable, we have a green light for calling ice_reuse_rx_page,
769 * which will assign the current buffer to the buffer that next_to_alloc is
770 * pointing to; otherwise, the DMA mapping needs to be destroyed and
771 * page freed
772 */
773 static bool
ice_can_reuse_rx_page(struct ice_rx_buf * rx_buf,int rx_buf_pgcnt)774 ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf, int rx_buf_pgcnt)
775 {
776 unsigned int pagecnt_bias = rx_buf->pagecnt_bias;
777 struct page *page = rx_buf->page;
778
779 /* avoid re-using remote pages */
780 if (unlikely(ice_page_is_reserved(page)))
781 return false;
782
783 #if (PAGE_SIZE < 8192)
784 /* if we are only owner of page we can reuse it */
785 if (unlikely((rx_buf_pgcnt - pagecnt_bias) > 1))
786 return false;
787 #else
788 #define ICE_LAST_OFFSET \
789 (SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_2048)
790 if (rx_buf->page_offset > ICE_LAST_OFFSET)
791 return false;
792 #endif /* PAGE_SIZE < 8192) */
793
794 /* If we have drained the page fragment pool we need to update
795 * the pagecnt_bias and page count so that we fully restock the
796 * number of references the driver holds.
797 */
798 if (unlikely(pagecnt_bias == 1)) {
799 page_ref_add(page, USHRT_MAX - 1);
800 rx_buf->pagecnt_bias = USHRT_MAX;
801 }
802
803 return true;
804 }
805
806 /**
807 * ice_add_rx_frag - Add contents of Rx buffer to sk_buff as a frag
808 * @rx_ring: Rx descriptor ring to transact packets on
809 * @rx_buf: buffer containing page to add
810 * @skb: sk_buff to place the data into
811 * @size: packet length from rx_desc
812 *
813 * This function will add the data contained in rx_buf->page to the skb.
814 * It will just attach the page as a frag to the skb.
815 * The function will then update the page offset.
816 */
817 static void
ice_add_rx_frag(struct ice_ring * rx_ring,struct ice_rx_buf * rx_buf,struct sk_buff * skb,unsigned int size)818 ice_add_rx_frag(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
819 struct sk_buff *skb, unsigned int size)
820 {
821 #if (PAGE_SIZE >= 8192)
822 unsigned int truesize = SKB_DATA_ALIGN(size + ice_rx_offset(rx_ring));
823 #else
824 unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
825 #endif
826
827 if (!size)
828 return;
829 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buf->page,
830 rx_buf->page_offset, size, truesize);
831
832 /* page is being used so we must update the page offset */
833 ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
834 }
835
836 /**
837 * ice_reuse_rx_page - page flip buffer and store it back on the ring
838 * @rx_ring: Rx descriptor ring to store buffers on
839 * @old_buf: donor buffer to have page reused
840 *
841 * Synchronizes page for reuse by the adapter
842 */
843 static void
ice_reuse_rx_page(struct ice_ring * rx_ring,struct ice_rx_buf * old_buf)844 ice_reuse_rx_page(struct ice_ring *rx_ring, struct ice_rx_buf *old_buf)
845 {
846 u16 nta = rx_ring->next_to_alloc;
847 struct ice_rx_buf *new_buf;
848
849 new_buf = &rx_ring->rx_buf[nta];
850
851 /* update, and store next to alloc */
852 nta++;
853 rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
854
855 /* Transfer page from old buffer to new buffer.
856 * Move each member individually to avoid possible store
857 * forwarding stalls and unnecessary copy of skb.
858 */
859 new_buf->dma = old_buf->dma;
860 new_buf->page = old_buf->page;
861 new_buf->page_offset = old_buf->page_offset;
862 new_buf->pagecnt_bias = old_buf->pagecnt_bias;
863 }
864
865 /**
866 * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
867 * @rx_ring: Rx descriptor ring to transact packets on
868 * @skb: skb to be used
869 * @size: size of buffer to add to skb
870 * @rx_buf_pgcnt: rx_buf page refcount
871 *
872 * This function will pull an Rx buffer from the ring and synchronize it
873 * for use by the CPU.
874 */
875 static struct ice_rx_buf *
ice_get_rx_buf(struct ice_ring * rx_ring,struct sk_buff ** skb,const unsigned int size,int * rx_buf_pgcnt)876 ice_get_rx_buf(struct ice_ring *rx_ring, struct sk_buff **skb,
877 const unsigned int size, int *rx_buf_pgcnt)
878 {
879 struct ice_rx_buf *rx_buf;
880
881 rx_buf = &rx_ring->rx_buf[rx_ring->next_to_clean];
882 *rx_buf_pgcnt =
883 #if (PAGE_SIZE < 8192)
884 page_count(rx_buf->page);
885 #else
886 0;
887 #endif
888 prefetchw(rx_buf->page);
889 *skb = rx_buf->skb;
890
891 if (!size)
892 return rx_buf;
893 /* we are reusing so sync this buffer for CPU use */
894 dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
895 rx_buf->page_offset, size,
896 DMA_FROM_DEVICE);
897
898 /* We have pulled a buffer for use, so decrement pagecnt_bias */
899 rx_buf->pagecnt_bias--;
900
901 return rx_buf;
902 }
903
904 /**
905 * ice_build_skb - Build skb around an existing buffer
906 * @rx_ring: Rx descriptor ring to transact packets on
907 * @rx_buf: Rx buffer to pull data from
908 * @xdp: xdp_buff pointing to the data
909 *
910 * This function builds an skb around an existing Rx buffer, taking care
911 * to set up the skb correctly and avoid any memcpy overhead.
912 */
913 static struct sk_buff *
ice_build_skb(struct ice_ring * rx_ring,struct ice_rx_buf * rx_buf,struct xdp_buff * xdp)914 ice_build_skb(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
915 struct xdp_buff *xdp)
916 {
917 u8 metasize = xdp->data - xdp->data_meta;
918 #if (PAGE_SIZE < 8192)
919 unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
920 #else
921 unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
922 SKB_DATA_ALIGN(xdp->data_end -
923 xdp->data_hard_start);
924 #endif
925 struct sk_buff *skb;
926
927 /* Prefetch first cache line of first page. If xdp->data_meta
928 * is unused, this points exactly as xdp->data, otherwise we
929 * likely have a consumer accessing first few bytes of meta
930 * data, and then actual data.
931 */
932 net_prefetch(xdp->data_meta);
933 /* build an skb around the page buffer */
934 skb = build_skb(xdp->data_hard_start, truesize);
935 if (unlikely(!skb))
936 return NULL;
937
938 /* must to record Rx queue, otherwise OS features such as
939 * symmetric queue won't work
940 */
941 skb_record_rx_queue(skb, rx_ring->q_index);
942
943 /* update pointers within the skb to store the data */
944 skb_reserve(skb, xdp->data - xdp->data_hard_start);
945 __skb_put(skb, xdp->data_end - xdp->data);
946 if (metasize)
947 skb_metadata_set(skb, metasize);
948
949 /* buffer is used by skb, update page_offset */
950 ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
951
952 return skb;
953 }
954
955 /**
956 * ice_construct_skb - Allocate skb and populate it
957 * @rx_ring: Rx descriptor ring to transact packets on
958 * @rx_buf: Rx buffer to pull data from
959 * @xdp: xdp_buff pointing to the data
960 *
961 * This function allocates an skb. It then populates it with the page
962 * data from the current receive descriptor, taking care to set up the
963 * skb correctly.
964 */
965 static struct sk_buff *
ice_construct_skb(struct ice_ring * rx_ring,struct ice_rx_buf * rx_buf,struct xdp_buff * xdp)966 ice_construct_skb(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
967 struct xdp_buff *xdp)
968 {
969 unsigned int size = xdp->data_end - xdp->data;
970 unsigned int headlen;
971 struct sk_buff *skb;
972
973 /* prefetch first cache line of first page */
974 net_prefetch(xdp->data);
975
976 /* allocate a skb to store the frags */
977 skb = __napi_alloc_skb(&rx_ring->q_vector->napi, ICE_RX_HDR_SIZE,
978 GFP_ATOMIC | __GFP_NOWARN);
979 if (unlikely(!skb))
980 return NULL;
981
982 skb_record_rx_queue(skb, rx_ring->q_index);
983 /* Determine available headroom for copy */
984 headlen = size;
985 if (headlen > ICE_RX_HDR_SIZE)
986 headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE);
987
988 /* align pull length to size of long to optimize memcpy performance */
989 memcpy(__skb_put(skb, headlen), xdp->data, ALIGN(headlen,
990 sizeof(long)));
991
992 /* if we exhaust the linear part then add what is left as a frag */
993 size -= headlen;
994 if (size) {
995 #if (PAGE_SIZE >= 8192)
996 unsigned int truesize = SKB_DATA_ALIGN(size);
997 #else
998 unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
999 #endif
1000 skb_add_rx_frag(skb, 0, rx_buf->page,
1001 rx_buf->page_offset + headlen, size, truesize);
1002 /* buffer is used by skb, update page_offset */
1003 ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
1004 } else {
1005 /* buffer is unused, reset bias back to rx_buf; data was copied
1006 * onto skb's linear part so there's no need for adjusting
1007 * page offset and we can reuse this buffer as-is
1008 */
1009 rx_buf->pagecnt_bias++;
1010 }
1011
1012 return skb;
1013 }
1014
1015 /**
1016 * ice_put_rx_buf - Clean up used buffer and either recycle or free
1017 * @rx_ring: Rx descriptor ring to transact packets on
1018 * @rx_buf: Rx buffer to pull data from
1019 * @rx_buf_pgcnt: Rx buffer page count pre xdp_do_redirect()
1020 *
1021 * This function will update next_to_clean and then clean up the contents
1022 * of the rx_buf. It will either recycle the buffer or unmap it and free
1023 * the associated resources.
1024 */
1025 static void
ice_put_rx_buf(struct ice_ring * rx_ring,struct ice_rx_buf * rx_buf,int rx_buf_pgcnt)1026 ice_put_rx_buf(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
1027 int rx_buf_pgcnt)
1028 {
1029 u16 ntc = rx_ring->next_to_clean + 1;
1030
1031 /* fetch, update, and store next to clean */
1032 ntc = (ntc < rx_ring->count) ? ntc : 0;
1033 rx_ring->next_to_clean = ntc;
1034
1035 if (!rx_buf)
1036 return;
1037
1038 if (ice_can_reuse_rx_page(rx_buf, rx_buf_pgcnt)) {
1039 /* hand second half of page back to the ring */
1040 ice_reuse_rx_page(rx_ring, rx_buf);
1041 } else {
1042 /* we are not reusing the buffer so unmap it */
1043 dma_unmap_page_attrs(rx_ring->dev, rx_buf->dma,
1044 ice_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
1045 ICE_RX_DMA_ATTR);
1046 __page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
1047 }
1048
1049 /* clear contents of buffer_info */
1050 rx_buf->page = NULL;
1051 rx_buf->skb = NULL;
1052 }
1053
1054 /**
1055 * ice_is_non_eop - process handling of non-EOP buffers
1056 * @rx_ring: Rx ring being processed
1057 * @rx_desc: Rx descriptor for current buffer
1058 * @skb: Current socket buffer containing buffer in progress
1059 *
1060 * If the buffer is an EOP buffer, this function exits returning false,
1061 * otherwise return true indicating that this is in fact a non-EOP buffer.
1062 */
1063 static bool
ice_is_non_eop(struct ice_ring * rx_ring,union ice_32b_rx_flex_desc * rx_desc,struct sk_buff * skb)1064 ice_is_non_eop(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
1065 struct sk_buff *skb)
1066 {
1067 /* if we are the last buffer then there is nothing else to do */
1068 #define ICE_RXD_EOF BIT(ICE_RX_FLEX_DESC_STATUS0_EOF_S)
1069 if (likely(ice_test_staterr(rx_desc, ICE_RXD_EOF)))
1070 return false;
1071
1072 /* place skb in next buffer to be received */
1073 rx_ring->rx_buf[rx_ring->next_to_clean].skb = skb;
1074 rx_ring->rx_stats.non_eop_descs++;
1075
1076 return true;
1077 }
1078
1079 /**
1080 * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1081 * @rx_ring: Rx descriptor ring to transact packets on
1082 * @budget: Total limit on number of packets to process
1083 *
1084 * This function provides a "bounce buffer" approach to Rx interrupt
1085 * processing. The advantage to this is that on systems that have
1086 * expensive overhead for IOMMU access this provides a means of avoiding
1087 * it by maintaining the mapping of the page to the system.
1088 *
1089 * Returns amount of work completed
1090 */
ice_clean_rx_irq(struct ice_ring * rx_ring,int budget)1091 int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget)
1092 {
1093 unsigned int total_rx_bytes = 0, total_rx_pkts = 0;
1094 u16 cleaned_count = ICE_DESC_UNUSED(rx_ring);
1095 unsigned int xdp_res, xdp_xmit = 0;
1096 struct bpf_prog *xdp_prog = NULL;
1097 struct xdp_buff xdp;
1098 bool failure;
1099
1100 xdp.rxq = &rx_ring->xdp_rxq;
1101 /* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
1102 #if (PAGE_SIZE < 8192)
1103 xdp.frame_sz = ice_rx_frame_truesize(rx_ring, 0);
1104 #endif
1105
1106 /* start the loop to process Rx packets bounded by 'budget' */
1107 while (likely(total_rx_pkts < (unsigned int)budget)) {
1108 union ice_32b_rx_flex_desc *rx_desc;
1109 struct ice_rx_buf *rx_buf;
1110 struct sk_buff *skb;
1111 unsigned int size;
1112 u16 stat_err_bits;
1113 int rx_buf_pgcnt;
1114 u16 vlan_tag = 0;
1115 u8 rx_ptype;
1116
1117 /* get the Rx desc from Rx ring based on 'next_to_clean' */
1118 rx_desc = ICE_RX_DESC(rx_ring, rx_ring->next_to_clean);
1119
1120 /* status_error_len will always be zero for unused descriptors
1121 * because it's cleared in cleanup, and overlaps with hdr_addr
1122 * which is always zero because packet split isn't used, if the
1123 * hardware wrote DD then it will be non-zero
1124 */
1125 stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1126 if (!ice_test_staterr(rx_desc, stat_err_bits))
1127 break;
1128
1129 /* This memory barrier is needed to keep us from reading
1130 * any other fields out of the rx_desc until we know the
1131 * DD bit is set.
1132 */
1133 dma_rmb();
1134
1135 if (rx_desc->wb.rxdid == FDIR_DESC_RXDID || !rx_ring->netdev) {
1136 ice_put_rx_buf(rx_ring, NULL, 0);
1137 cleaned_count++;
1138 continue;
1139 }
1140
1141 size = le16_to_cpu(rx_desc->wb.pkt_len) &
1142 ICE_RX_FLX_DESC_PKT_LEN_M;
1143
1144 /* retrieve a buffer from the ring */
1145 rx_buf = ice_get_rx_buf(rx_ring, &skb, size, &rx_buf_pgcnt);
1146
1147 if (!size) {
1148 xdp.data = NULL;
1149 xdp.data_end = NULL;
1150 xdp.data_hard_start = NULL;
1151 xdp.data_meta = NULL;
1152 goto construct_skb;
1153 }
1154
1155 xdp.data = page_address(rx_buf->page) + rx_buf->page_offset;
1156 xdp.data_hard_start = xdp.data - ice_rx_offset(rx_ring);
1157 xdp.data_meta = xdp.data;
1158 xdp.data_end = xdp.data + size;
1159 #if (PAGE_SIZE > 4096)
1160 /* At larger PAGE_SIZE, frame_sz depend on len size */
1161 xdp.frame_sz = ice_rx_frame_truesize(rx_ring, size);
1162 #endif
1163
1164 rcu_read_lock();
1165 xdp_prog = READ_ONCE(rx_ring->xdp_prog);
1166 if (!xdp_prog) {
1167 rcu_read_unlock();
1168 goto construct_skb;
1169 }
1170
1171 xdp_res = ice_run_xdp(rx_ring, &xdp, xdp_prog);
1172 rcu_read_unlock();
1173 if (!xdp_res)
1174 goto construct_skb;
1175 if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) {
1176 xdp_xmit |= xdp_res;
1177 ice_rx_buf_adjust_pg_offset(rx_buf, xdp.frame_sz);
1178 } else {
1179 rx_buf->pagecnt_bias++;
1180 }
1181 total_rx_bytes += size;
1182 total_rx_pkts++;
1183
1184 cleaned_count++;
1185 ice_put_rx_buf(rx_ring, rx_buf, rx_buf_pgcnt);
1186 continue;
1187 construct_skb:
1188 if (skb) {
1189 ice_add_rx_frag(rx_ring, rx_buf, skb, size);
1190 } else if (likely(xdp.data)) {
1191 if (ice_ring_uses_build_skb(rx_ring))
1192 skb = ice_build_skb(rx_ring, rx_buf, &xdp);
1193 else
1194 skb = ice_construct_skb(rx_ring, rx_buf, &xdp);
1195 }
1196 /* exit if we failed to retrieve a buffer */
1197 if (!skb) {
1198 rx_ring->rx_stats.alloc_buf_failed++;
1199 if (rx_buf)
1200 rx_buf->pagecnt_bias++;
1201 break;
1202 }
1203
1204 ice_put_rx_buf(rx_ring, rx_buf, rx_buf_pgcnt);
1205 cleaned_count++;
1206
1207 /* skip if it is NOP desc */
1208 if (ice_is_non_eop(rx_ring, rx_desc, skb))
1209 continue;
1210
1211 stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);
1212 if (unlikely(ice_test_staterr(rx_desc, stat_err_bits))) {
1213 dev_kfree_skb_any(skb);
1214 continue;
1215 }
1216
1217 stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_L2TAG1P_S);
1218 if (ice_test_staterr(rx_desc, stat_err_bits))
1219 vlan_tag = le16_to_cpu(rx_desc->wb.l2tag1);
1220
1221 /* pad the skb if needed, to make a valid ethernet frame */
1222 if (eth_skb_pad(skb)) {
1223 skb = NULL;
1224 continue;
1225 }
1226
1227 /* probably a little skewed due to removing CRC */
1228 total_rx_bytes += skb->len;
1229
1230 /* populate checksum, VLAN, and protocol */
1231 rx_ptype = le16_to_cpu(rx_desc->wb.ptype_flex_flags0) &
1232 ICE_RX_FLEX_DESC_PTYPE_M;
1233
1234 ice_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
1235
1236 /* send completed skb up the stack */
1237 ice_receive_skb(rx_ring, skb, vlan_tag);
1238
1239 /* update budget accounting */
1240 total_rx_pkts++;
1241 }
1242
1243 /* return up to cleaned_count buffers to hardware */
1244 failure = ice_alloc_rx_bufs(rx_ring, cleaned_count);
1245
1246 if (xdp_prog)
1247 ice_finalize_xdp_rx(rx_ring, xdp_xmit);
1248
1249 ice_update_rx_ring_stats(rx_ring, total_rx_pkts, total_rx_bytes);
1250
1251 /* guarantee a trip back through this routine if there was a failure */
1252 return failure ? budget : (int)total_rx_pkts;
1253 }
1254
1255 /**
1256 * ice_adjust_itr_by_size_and_speed - Adjust ITR based on current traffic
1257 * @port_info: port_info structure containing the current link speed
1258 * @avg_pkt_size: average size of Tx or Rx packets based on clean routine
1259 * @itr: ITR value to update
1260 *
1261 * Calculate how big of an increment should be applied to the ITR value passed
1262 * in based on wmem_default, SKB overhead, ethernet overhead, and the current
1263 * link speed.
1264 *
1265 * The following is a calculation derived from:
1266 * wmem_default / (size + overhead) = desired_pkts_per_int
1267 * rate / bits_per_byte / (size + ethernet overhead) = pkt_rate
1268 * (desired_pkt_rate / pkt_rate) * usecs_per_sec = ITR value
1269 *
1270 * Assuming wmem_default is 212992 and overhead is 640 bytes per
1271 * packet, (256 skb, 64 headroom, 320 shared info), we can reduce the
1272 * formula down to:
1273 *
1274 * wmem_default * bits_per_byte * usecs_per_sec pkt_size + 24
1275 * ITR = -------------------------------------------- * --------------
1276 * rate pkt_size + 640
1277 */
1278 static unsigned int
ice_adjust_itr_by_size_and_speed(struct ice_port_info * port_info,unsigned int avg_pkt_size,unsigned int itr)1279 ice_adjust_itr_by_size_and_speed(struct ice_port_info *port_info,
1280 unsigned int avg_pkt_size,
1281 unsigned int itr)
1282 {
1283 switch (port_info->phy.link_info.link_speed) {
1284 case ICE_AQ_LINK_SPEED_100GB:
1285 itr += DIV_ROUND_UP(17 * (avg_pkt_size + 24),
1286 avg_pkt_size + 640);
1287 break;
1288 case ICE_AQ_LINK_SPEED_50GB:
1289 itr += DIV_ROUND_UP(34 * (avg_pkt_size + 24),
1290 avg_pkt_size + 640);
1291 break;
1292 case ICE_AQ_LINK_SPEED_40GB:
1293 itr += DIV_ROUND_UP(43 * (avg_pkt_size + 24),
1294 avg_pkt_size + 640);
1295 break;
1296 case ICE_AQ_LINK_SPEED_25GB:
1297 itr += DIV_ROUND_UP(68 * (avg_pkt_size + 24),
1298 avg_pkt_size + 640);
1299 break;
1300 case ICE_AQ_LINK_SPEED_20GB:
1301 itr += DIV_ROUND_UP(85 * (avg_pkt_size + 24),
1302 avg_pkt_size + 640);
1303 break;
1304 case ICE_AQ_LINK_SPEED_10GB:
1305 default:
1306 itr += DIV_ROUND_UP(170 * (avg_pkt_size + 24),
1307 avg_pkt_size + 640);
1308 break;
1309 }
1310
1311 if ((itr & ICE_ITR_MASK) > ICE_ITR_ADAPTIVE_MAX_USECS) {
1312 itr &= ICE_ITR_ADAPTIVE_LATENCY;
1313 itr += ICE_ITR_ADAPTIVE_MAX_USECS;
1314 }
1315
1316 return itr;
1317 }
1318
1319 /**
1320 * ice_update_itr - update the adaptive ITR value based on statistics
1321 * @q_vector: structure containing interrupt and ring information
1322 * @rc: structure containing ring performance data
1323 *
1324 * Stores a new ITR value based on packets and byte
1325 * counts during the last interrupt. The advantage of per interrupt
1326 * computation is faster updates and more accurate ITR for the current
1327 * traffic pattern. Constants in this function were computed
1328 * based on theoretical maximum wire speed and thresholds were set based
1329 * on testing data as well as attempting to minimize response time
1330 * while increasing bulk throughput.
1331 */
1332 static void
ice_update_itr(struct ice_q_vector * q_vector,struct ice_ring_container * rc)1333 ice_update_itr(struct ice_q_vector *q_vector, struct ice_ring_container *rc)
1334 {
1335 unsigned long next_update = jiffies;
1336 unsigned int packets, bytes, itr;
1337 bool container_is_rx;
1338
1339 if (!rc->ring || !ITR_IS_DYNAMIC(rc->itr_setting))
1340 return;
1341
1342 /* If itr_countdown is set it means we programmed an ITR within
1343 * the last 4 interrupt cycles. This has a side effect of us
1344 * potentially firing an early interrupt. In order to work around
1345 * this we need to throw out any data received for a few
1346 * interrupts following the update.
1347 */
1348 if (q_vector->itr_countdown) {
1349 itr = rc->target_itr;
1350 goto clear_counts;
1351 }
1352
1353 container_is_rx = (&q_vector->rx == rc);
1354 /* For Rx we want to push the delay up and default to low latency.
1355 * for Tx we want to pull the delay down and default to high latency.
1356 */
1357 itr = container_is_rx ?
1358 ICE_ITR_ADAPTIVE_MIN_USECS | ICE_ITR_ADAPTIVE_LATENCY :
1359 ICE_ITR_ADAPTIVE_MAX_USECS | ICE_ITR_ADAPTIVE_LATENCY;
1360
1361 /* If we didn't update within up to 1 - 2 jiffies we can assume
1362 * that either packets are coming in so slow there hasn't been
1363 * any work, or that there is so much work that NAPI is dealing
1364 * with interrupt moderation and we don't need to do anything.
1365 */
1366 if (time_after(next_update, rc->next_update))
1367 goto clear_counts;
1368
1369 prefetch(q_vector->vsi->port_info);
1370
1371 packets = rc->total_pkts;
1372 bytes = rc->total_bytes;
1373
1374 if (container_is_rx) {
1375 /* If Rx there are 1 to 4 packets and bytes are less than
1376 * 9000 assume insufficient data to use bulk rate limiting
1377 * approach unless Tx is already in bulk rate limiting. We
1378 * are likely latency driven.
1379 */
1380 if (packets && packets < 4 && bytes < 9000 &&
1381 (q_vector->tx.target_itr & ICE_ITR_ADAPTIVE_LATENCY)) {
1382 itr = ICE_ITR_ADAPTIVE_LATENCY;
1383 goto adjust_by_size_and_speed;
1384 }
1385 } else if (packets < 4) {
1386 /* If we have Tx and Rx ITR maxed and Tx ITR is running in
1387 * bulk mode and we are receiving 4 or fewer packets just
1388 * reset the ITR_ADAPTIVE_LATENCY bit for latency mode so
1389 * that the Rx can relax.
1390 */
1391 if (rc->target_itr == ICE_ITR_ADAPTIVE_MAX_USECS &&
1392 (q_vector->rx.target_itr & ICE_ITR_MASK) ==
1393 ICE_ITR_ADAPTIVE_MAX_USECS)
1394 goto clear_counts;
1395 } else if (packets > 32) {
1396 /* If we have processed over 32 packets in a single interrupt
1397 * for Tx assume we need to switch over to "bulk" mode.
1398 */
1399 rc->target_itr &= ~ICE_ITR_ADAPTIVE_LATENCY;
1400 }
1401
1402 /* We have no packets to actually measure against. This means
1403 * either one of the other queues on this vector is active or
1404 * we are a Tx queue doing TSO with too high of an interrupt rate.
1405 *
1406 * Between 4 and 56 we can assume that our current interrupt delay
1407 * is only slightly too low. As such we should increase it by a small
1408 * fixed amount.
1409 */
1410 if (packets < 56) {
1411 itr = rc->target_itr + ICE_ITR_ADAPTIVE_MIN_INC;
1412 if ((itr & ICE_ITR_MASK) > ICE_ITR_ADAPTIVE_MAX_USECS) {
1413 itr &= ICE_ITR_ADAPTIVE_LATENCY;
1414 itr += ICE_ITR_ADAPTIVE_MAX_USECS;
1415 }
1416 goto clear_counts;
1417 }
1418
1419 if (packets <= 256) {
1420 itr = min(q_vector->tx.current_itr, q_vector->rx.current_itr);
1421 itr &= ICE_ITR_MASK;
1422
1423 /* Between 56 and 112 is our "goldilocks" zone where we are
1424 * working out "just right". Just report that our current
1425 * ITR is good for us.
1426 */
1427 if (packets <= 112)
1428 goto clear_counts;
1429
1430 /* If packet count is 128 or greater we are likely looking
1431 * at a slight overrun of the delay we want. Try halving
1432 * our delay to see if that will cut the number of packets
1433 * in half per interrupt.
1434 */
1435 itr >>= 1;
1436 itr &= ICE_ITR_MASK;
1437 if (itr < ICE_ITR_ADAPTIVE_MIN_USECS)
1438 itr = ICE_ITR_ADAPTIVE_MIN_USECS;
1439
1440 goto clear_counts;
1441 }
1442
1443 /* The paths below assume we are dealing with a bulk ITR since
1444 * number of packets is greater than 256. We are just going to have
1445 * to compute a value and try to bring the count under control,
1446 * though for smaller packet sizes there isn't much we can do as
1447 * NAPI polling will likely be kicking in sooner rather than later.
1448 */
1449 itr = ICE_ITR_ADAPTIVE_BULK;
1450
1451 adjust_by_size_and_speed:
1452
1453 /* based on checks above packets cannot be 0 so division is safe */
1454 itr = ice_adjust_itr_by_size_and_speed(q_vector->vsi->port_info,
1455 bytes / packets, itr);
1456
1457 clear_counts:
1458 /* write back value */
1459 rc->target_itr = itr;
1460
1461 /* next update should occur within next jiffy */
1462 rc->next_update = next_update + 1;
1463
1464 rc->total_bytes = 0;
1465 rc->total_pkts = 0;
1466 }
1467
1468 /**
1469 * ice_buildreg_itr - build value for writing to the GLINT_DYN_CTL register
1470 * @itr_idx: interrupt throttling index
1471 * @itr: interrupt throttling value in usecs
1472 */
ice_buildreg_itr(u16 itr_idx,u16 itr)1473 static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
1474 {
1475 /* The ITR value is reported in microseconds, and the register value is
1476 * recorded in 2 microsecond units. For this reason we only need to
1477 * shift by the GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S to apply this
1478 * granularity as a shift instead of division. The mask makes sure the
1479 * ITR value is never odd so we don't accidentally write into the field
1480 * prior to the ITR field.
1481 */
1482 itr &= ICE_ITR_MASK;
1483
1484 return GLINT_DYN_CTL_INTENA_M | GLINT_DYN_CTL_CLEARPBA_M |
1485 (itr_idx << GLINT_DYN_CTL_ITR_INDX_S) |
1486 (itr << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S));
1487 }
1488
1489 /* The act of updating the ITR will cause it to immediately trigger. In order
1490 * to prevent this from throwing off adaptive update statistics we defer the
1491 * update so that it can only happen so often. So after either Tx or Rx are
1492 * updated we make the adaptive scheme wait until either the ITR completely
1493 * expires via the next_update expiration or we have been through at least
1494 * 3 interrupts.
1495 */
1496 #define ITR_COUNTDOWN_START 3
1497
1498 /**
1499 * ice_update_ena_itr - Update ITR and re-enable MSIX interrupt
1500 * @q_vector: q_vector for which ITR is being updated and interrupt enabled
1501 */
ice_update_ena_itr(struct ice_q_vector * q_vector)1502 static void ice_update_ena_itr(struct ice_q_vector *q_vector)
1503 {
1504 struct ice_ring_container *tx = &q_vector->tx;
1505 struct ice_ring_container *rx = &q_vector->rx;
1506 struct ice_vsi *vsi = q_vector->vsi;
1507 u32 itr_val;
1508
1509 /* when exiting WB_ON_ITR lets set a low ITR value and trigger
1510 * interrupts to expire right away in case we have more work ready to go
1511 * already
1512 */
1513 if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE) {
1514 itr_val = ice_buildreg_itr(rx->itr_idx, ICE_WB_ON_ITR_USECS);
1515 wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
1516 /* set target back to last user set value */
1517 rx->target_itr = rx->itr_setting;
1518 /* set current to what we just wrote and dynamic if needed */
1519 rx->current_itr = ICE_WB_ON_ITR_USECS |
1520 (rx->itr_setting & ICE_ITR_DYNAMIC);
1521 /* allow normal interrupt flow to start */
1522 q_vector->itr_countdown = 0;
1523 return;
1524 }
1525
1526 /* This will do nothing if dynamic updates are not enabled */
1527 ice_update_itr(q_vector, tx);
1528 ice_update_itr(q_vector, rx);
1529
1530 /* This block of logic allows us to get away with only updating
1531 * one ITR value with each interrupt. The idea is to perform a
1532 * pseudo-lazy update with the following criteria.
1533 *
1534 * 1. Rx is given higher priority than Tx if both are in same state
1535 * 2. If we must reduce an ITR that is given highest priority.
1536 * 3. We then give priority to increasing ITR based on amount.
1537 */
1538 if (rx->target_itr < rx->current_itr) {
1539 /* Rx ITR needs to be reduced, this is highest priority */
1540 itr_val = ice_buildreg_itr(rx->itr_idx, rx->target_itr);
1541 rx->current_itr = rx->target_itr;
1542 q_vector->itr_countdown = ITR_COUNTDOWN_START;
1543 } else if ((tx->target_itr < tx->current_itr) ||
1544 ((rx->target_itr - rx->current_itr) <
1545 (tx->target_itr - tx->current_itr))) {
1546 /* Tx ITR needs to be reduced, this is second priority
1547 * Tx ITR needs to be increased more than Rx, fourth priority
1548 */
1549 itr_val = ice_buildreg_itr(tx->itr_idx, tx->target_itr);
1550 tx->current_itr = tx->target_itr;
1551 q_vector->itr_countdown = ITR_COUNTDOWN_START;
1552 } else if (rx->current_itr != rx->target_itr) {
1553 /* Rx ITR needs to be increased, third priority */
1554 itr_val = ice_buildreg_itr(rx->itr_idx, rx->target_itr);
1555 rx->current_itr = rx->target_itr;
1556 q_vector->itr_countdown = ITR_COUNTDOWN_START;
1557 } else {
1558 /* Still have to re-enable the interrupts */
1559 itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
1560 if (q_vector->itr_countdown)
1561 q_vector->itr_countdown--;
1562 }
1563
1564 if (!test_bit(__ICE_DOWN, q_vector->vsi->state))
1565 wr32(&q_vector->vsi->back->hw,
1566 GLINT_DYN_CTL(q_vector->reg_idx),
1567 itr_val);
1568 }
1569
1570 /**
1571 * ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
1572 * @q_vector: q_vector to set WB_ON_ITR on
1573 *
1574 * We need to tell hardware to write-back completed descriptors even when
1575 * interrupts are disabled. Descriptors will be written back on cache line
1576 * boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
1577 * descriptors may not be written back if they don't fill a cache line until the
1578 * next interrupt.
1579 *
1580 * This sets the write-back frequency to 2 microseconds as that is the minimum
1581 * value that's not 0 due to ITR granularity. Also, set the INTENA_MSK bit to
1582 * make sure hardware knows we aren't meddling with the INTENA_M bit.
1583 */
ice_set_wb_on_itr(struct ice_q_vector * q_vector)1584 static void ice_set_wb_on_itr(struct ice_q_vector *q_vector)
1585 {
1586 struct ice_vsi *vsi = q_vector->vsi;
1587
1588 /* already in WB_ON_ITR mode no need to change it */
1589 if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE)
1590 return;
1591
1592 if (q_vector->num_ring_rx)
1593 wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1594 ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
1595 ICE_RX_ITR));
1596
1597 if (q_vector->num_ring_tx)
1598 wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1599 ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
1600 ICE_TX_ITR));
1601
1602 q_vector->itr_countdown = ICE_IN_WB_ON_ITR_MODE;
1603 }
1604
1605 /**
1606 * ice_napi_poll - NAPI polling Rx/Tx cleanup routine
1607 * @napi: napi struct with our devices info in it
1608 * @budget: amount of work driver is allowed to do this pass, in packets
1609 *
1610 * This function will clean all queues associated with a q_vector.
1611 *
1612 * Returns the amount of work done
1613 */
ice_napi_poll(struct napi_struct * napi,int budget)1614 int ice_napi_poll(struct napi_struct *napi, int budget)
1615 {
1616 struct ice_q_vector *q_vector =
1617 container_of(napi, struct ice_q_vector, napi);
1618 bool clean_complete = true;
1619 struct ice_ring *ring;
1620 int budget_per_ring;
1621 int work_done = 0;
1622
1623 /* Since the actual Tx work is minimal, we can give the Tx a larger
1624 * budget and be more aggressive about cleaning up the Tx descriptors.
1625 */
1626 ice_for_each_ring(ring, q_vector->tx) {
1627 bool wd = ring->xsk_pool ?
1628 ice_clean_tx_irq_zc(ring, budget) :
1629 ice_clean_tx_irq(ring, budget);
1630
1631 if (!wd)
1632 clean_complete = false;
1633 }
1634
1635 /* Handle case where we are called by netpoll with a budget of 0 */
1636 if (unlikely(budget <= 0))
1637 return budget;
1638
1639 /* normally we have 1 Rx ring per q_vector */
1640 if (unlikely(q_vector->num_ring_rx > 1))
1641 /* We attempt to distribute budget to each Rx queue fairly, but
1642 * don't allow the budget to go below 1 because that would exit
1643 * polling early.
1644 */
1645 budget_per_ring = max_t(int, budget / q_vector->num_ring_rx, 1);
1646 else
1647 /* Max of 1 Rx ring in this q_vector so give it the budget */
1648 budget_per_ring = budget;
1649
1650 ice_for_each_ring(ring, q_vector->rx) {
1651 int cleaned;
1652
1653 /* A dedicated path for zero-copy allows making a single
1654 * comparison in the irq context instead of many inside the
1655 * ice_clean_rx_irq function and makes the codebase cleaner.
1656 */
1657 cleaned = ring->xsk_pool ?
1658 ice_clean_rx_irq_zc(ring, budget_per_ring) :
1659 ice_clean_rx_irq(ring, budget_per_ring);
1660 work_done += cleaned;
1661 /* if we clean as many as budgeted, we must not be done */
1662 if (cleaned >= budget_per_ring)
1663 clean_complete = false;
1664 }
1665
1666 /* If work not completed, return budget and polling will return */
1667 if (!clean_complete)
1668 return budget;
1669
1670 /* Exit the polling mode, but don't re-enable interrupts if stack might
1671 * poll us due to busy-polling
1672 */
1673 if (likely(napi_complete_done(napi, work_done)))
1674 ice_update_ena_itr(q_vector);
1675 else
1676 ice_set_wb_on_itr(q_vector);
1677
1678 return min_t(int, work_done, budget - 1);
1679 }
1680
1681 /**
1682 * __ice_maybe_stop_tx - 2nd level check for Tx stop conditions
1683 * @tx_ring: the ring to be checked
1684 * @size: the size buffer we want to assure is available
1685 *
1686 * Returns -EBUSY if a stop is needed, else 0
1687 */
__ice_maybe_stop_tx(struct ice_ring * tx_ring,unsigned int size)1688 static int __ice_maybe_stop_tx(struct ice_ring *tx_ring, unsigned int size)
1689 {
1690 netif_stop_subqueue(tx_ring->netdev, tx_ring->q_index);
1691 /* Memory barrier before checking head and tail */
1692 smp_mb();
1693
1694 /* Check again in a case another CPU has just made room available. */
1695 if (likely(ICE_DESC_UNUSED(tx_ring) < size))
1696 return -EBUSY;
1697
1698 /* A reprieve! - use start_subqueue because it doesn't call schedule */
1699 netif_start_subqueue(tx_ring->netdev, tx_ring->q_index);
1700 ++tx_ring->tx_stats.restart_q;
1701 return 0;
1702 }
1703
1704 /**
1705 * ice_maybe_stop_tx - 1st level check for Tx stop conditions
1706 * @tx_ring: the ring to be checked
1707 * @size: the size buffer we want to assure is available
1708 *
1709 * Returns 0 if stop is not needed
1710 */
ice_maybe_stop_tx(struct ice_ring * tx_ring,unsigned int size)1711 static int ice_maybe_stop_tx(struct ice_ring *tx_ring, unsigned int size)
1712 {
1713 if (likely(ICE_DESC_UNUSED(tx_ring) >= size))
1714 return 0;
1715
1716 return __ice_maybe_stop_tx(tx_ring, size);
1717 }
1718
1719 /**
1720 * ice_tx_map - Build the Tx descriptor
1721 * @tx_ring: ring to send buffer on
1722 * @first: first buffer info buffer to use
1723 * @off: pointer to struct that holds offload parameters
1724 *
1725 * This function loops over the skb data pointed to by *first
1726 * and gets a physical address for each memory location and programs
1727 * it and the length into the transmit descriptor.
1728 */
1729 static void
ice_tx_map(struct ice_ring * tx_ring,struct ice_tx_buf * first,struct ice_tx_offload_params * off)1730 ice_tx_map(struct ice_ring *tx_ring, struct ice_tx_buf *first,
1731 struct ice_tx_offload_params *off)
1732 {
1733 u64 td_offset, td_tag, td_cmd;
1734 u16 i = tx_ring->next_to_use;
1735 unsigned int data_len, size;
1736 struct ice_tx_desc *tx_desc;
1737 struct ice_tx_buf *tx_buf;
1738 struct sk_buff *skb;
1739 skb_frag_t *frag;
1740 dma_addr_t dma;
1741
1742 td_tag = off->td_l2tag1;
1743 td_cmd = off->td_cmd;
1744 td_offset = off->td_offset;
1745 skb = first->skb;
1746
1747 data_len = skb->data_len;
1748 size = skb_headlen(skb);
1749
1750 tx_desc = ICE_TX_DESC(tx_ring, i);
1751
1752 if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
1753 td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
1754 td_tag = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
1755 ICE_TX_FLAGS_VLAN_S;
1756 }
1757
1758 dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1759
1760 tx_buf = first;
1761
1762 for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1763 unsigned int max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1764
1765 if (dma_mapping_error(tx_ring->dev, dma))
1766 goto dma_error;
1767
1768 /* record length, and DMA address */
1769 dma_unmap_len_set(tx_buf, len, size);
1770 dma_unmap_addr_set(tx_buf, dma, dma);
1771
1772 /* align size to end of page */
1773 max_data += -dma & (ICE_MAX_READ_REQ_SIZE - 1);
1774 tx_desc->buf_addr = cpu_to_le64(dma);
1775
1776 /* account for data chunks larger than the hardware
1777 * can handle
1778 */
1779 while (unlikely(size > ICE_MAX_DATA_PER_TXD)) {
1780 tx_desc->cmd_type_offset_bsz =
1781 ice_build_ctob(td_cmd, td_offset, max_data,
1782 td_tag);
1783
1784 tx_desc++;
1785 i++;
1786
1787 if (i == tx_ring->count) {
1788 tx_desc = ICE_TX_DESC(tx_ring, 0);
1789 i = 0;
1790 }
1791
1792 dma += max_data;
1793 size -= max_data;
1794
1795 max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1796 tx_desc->buf_addr = cpu_to_le64(dma);
1797 }
1798
1799 if (likely(!data_len))
1800 break;
1801
1802 tx_desc->cmd_type_offset_bsz = ice_build_ctob(td_cmd, td_offset,
1803 size, td_tag);
1804
1805 tx_desc++;
1806 i++;
1807
1808 if (i == tx_ring->count) {
1809 tx_desc = ICE_TX_DESC(tx_ring, 0);
1810 i = 0;
1811 }
1812
1813 size = skb_frag_size(frag);
1814 data_len -= size;
1815
1816 dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1817 DMA_TO_DEVICE);
1818
1819 tx_buf = &tx_ring->tx_buf[i];
1820 }
1821
1822 /* record bytecount for BQL */
1823 netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
1824
1825 /* record SW timestamp if HW timestamp is not available */
1826 skb_tx_timestamp(first->skb);
1827
1828 i++;
1829 if (i == tx_ring->count)
1830 i = 0;
1831
1832 /* write last descriptor with RS and EOP bits */
1833 td_cmd |= (u64)ICE_TXD_LAST_DESC_CMD;
1834 tx_desc->cmd_type_offset_bsz =
1835 ice_build_ctob(td_cmd, td_offset, size, td_tag);
1836
1837 /* Force memory writes to complete before letting h/w know there
1838 * are new descriptors to fetch.
1839 *
1840 * We also use this memory barrier to make certain all of the
1841 * status bits have been updated before next_to_watch is written.
1842 */
1843 wmb();
1844
1845 /* set next_to_watch value indicating a packet is present */
1846 first->next_to_watch = tx_desc;
1847
1848 tx_ring->next_to_use = i;
1849
1850 ice_maybe_stop_tx(tx_ring, DESC_NEEDED);
1851
1852 /* notify HW of packet */
1853 if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more())
1854 writel(i, tx_ring->tail);
1855
1856 return;
1857
1858 dma_error:
1859 /* clear DMA mappings for failed tx_buf map */
1860 for (;;) {
1861 tx_buf = &tx_ring->tx_buf[i];
1862 ice_unmap_and_free_tx_buf(tx_ring, tx_buf);
1863 if (tx_buf == first)
1864 break;
1865 if (i == 0)
1866 i = tx_ring->count;
1867 i--;
1868 }
1869
1870 tx_ring->next_to_use = i;
1871 }
1872
1873 /**
1874 * ice_tx_csum - Enable Tx checksum offloads
1875 * @first: pointer to the first descriptor
1876 * @off: pointer to struct that holds offload parameters
1877 *
1878 * Returns 0 or error (negative) if checksum offload can't happen, 1 otherwise.
1879 */
1880 static
ice_tx_csum(struct ice_tx_buf * first,struct ice_tx_offload_params * off)1881 int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
1882 {
1883 u32 l4_len = 0, l3_len = 0, l2_len = 0;
1884 struct sk_buff *skb = first->skb;
1885 union {
1886 struct iphdr *v4;
1887 struct ipv6hdr *v6;
1888 unsigned char *hdr;
1889 } ip;
1890 union {
1891 struct tcphdr *tcp;
1892 unsigned char *hdr;
1893 } l4;
1894 __be16 frag_off, protocol;
1895 unsigned char *exthdr;
1896 u32 offset, cmd = 0;
1897 u8 l4_proto = 0;
1898
1899 if (skb->ip_summed != CHECKSUM_PARTIAL)
1900 return 0;
1901
1902 ip.hdr = skb_network_header(skb);
1903 l4.hdr = skb_transport_header(skb);
1904
1905 /* compute outer L2 header size */
1906 l2_len = ip.hdr - skb->data;
1907 offset = (l2_len / 2) << ICE_TX_DESC_LEN_MACLEN_S;
1908
1909 protocol = vlan_get_protocol(skb);
1910
1911 if (protocol == htons(ETH_P_IP))
1912 first->tx_flags |= ICE_TX_FLAGS_IPV4;
1913 else if (protocol == htons(ETH_P_IPV6))
1914 first->tx_flags |= ICE_TX_FLAGS_IPV6;
1915
1916 if (skb->encapsulation) {
1917 bool gso_ena = false;
1918 u32 tunnel = 0;
1919
1920 /* define outer network header type */
1921 if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1922 tunnel |= (first->tx_flags & ICE_TX_FLAGS_TSO) ?
1923 ICE_TX_CTX_EIPT_IPV4 :
1924 ICE_TX_CTX_EIPT_IPV4_NO_CSUM;
1925 l4_proto = ip.v4->protocol;
1926 } else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1927 int ret;
1928
1929 tunnel |= ICE_TX_CTX_EIPT_IPV6;
1930 exthdr = ip.hdr + sizeof(*ip.v6);
1931 l4_proto = ip.v6->nexthdr;
1932 ret = ipv6_skip_exthdr(skb, exthdr - skb->data,
1933 &l4_proto, &frag_off);
1934 if (ret < 0)
1935 return -1;
1936 }
1937
1938 /* define outer transport */
1939 switch (l4_proto) {
1940 case IPPROTO_UDP:
1941 tunnel |= ICE_TXD_CTX_UDP_TUNNELING;
1942 first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1943 break;
1944 case IPPROTO_GRE:
1945 tunnel |= ICE_TXD_CTX_GRE_TUNNELING;
1946 first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1947 break;
1948 case IPPROTO_IPIP:
1949 case IPPROTO_IPV6:
1950 first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1951 l4.hdr = skb_inner_network_header(skb);
1952 break;
1953 default:
1954 if (first->tx_flags & ICE_TX_FLAGS_TSO)
1955 return -1;
1956
1957 skb_checksum_help(skb);
1958 return 0;
1959 }
1960
1961 /* compute outer L3 header size */
1962 tunnel |= ((l4.hdr - ip.hdr) / 4) <<
1963 ICE_TXD_CTX_QW0_EIPLEN_S;
1964
1965 /* switch IP header pointer from outer to inner header */
1966 ip.hdr = skb_inner_network_header(skb);
1967
1968 /* compute tunnel header size */
1969 tunnel |= ((ip.hdr - l4.hdr) / 2) <<
1970 ICE_TXD_CTX_QW0_NATLEN_S;
1971
1972 gso_ena = skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL;
1973 /* indicate if we need to offload outer UDP header */
1974 if ((first->tx_flags & ICE_TX_FLAGS_TSO) && !gso_ena &&
1975 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
1976 tunnel |= ICE_TXD_CTX_QW0_L4T_CS_M;
1977
1978 /* record tunnel offload values */
1979 off->cd_tunnel_params |= tunnel;
1980
1981 /* set DTYP=1 to indicate that it's an Tx context descriptor
1982 * in IPsec tunnel mode with Tx offloads in Quad word 1
1983 */
1984 off->cd_qw1 |= (u64)ICE_TX_DESC_DTYPE_CTX;
1985
1986 /* switch L4 header pointer from outer to inner */
1987 l4.hdr = skb_inner_transport_header(skb);
1988 l4_proto = 0;
1989
1990 /* reset type as we transition from outer to inner headers */
1991 first->tx_flags &= ~(ICE_TX_FLAGS_IPV4 | ICE_TX_FLAGS_IPV6);
1992 if (ip.v4->version == 4)
1993 first->tx_flags |= ICE_TX_FLAGS_IPV4;
1994 if (ip.v6->version == 6)
1995 first->tx_flags |= ICE_TX_FLAGS_IPV6;
1996 }
1997
1998 /* Enable IP checksum offloads */
1999 if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
2000 l4_proto = ip.v4->protocol;
2001 /* the stack computes the IP header already, the only time we
2002 * need the hardware to recompute it is in the case of TSO.
2003 */
2004 if (first->tx_flags & ICE_TX_FLAGS_TSO)
2005 cmd |= ICE_TX_DESC_CMD_IIPT_IPV4_CSUM;
2006 else
2007 cmd |= ICE_TX_DESC_CMD_IIPT_IPV4;
2008
2009 } else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
2010 cmd |= ICE_TX_DESC_CMD_IIPT_IPV6;
2011 exthdr = ip.hdr + sizeof(*ip.v6);
2012 l4_proto = ip.v6->nexthdr;
2013 if (l4.hdr != exthdr)
2014 ipv6_skip_exthdr(skb, exthdr - skb->data, &l4_proto,
2015 &frag_off);
2016 } else {
2017 return -1;
2018 }
2019
2020 /* compute inner L3 header size */
2021 l3_len = l4.hdr - ip.hdr;
2022 offset |= (l3_len / 4) << ICE_TX_DESC_LEN_IPLEN_S;
2023
2024 /* Enable L4 checksum offloads */
2025 switch (l4_proto) {
2026 case IPPROTO_TCP:
2027 /* enable checksum offloads */
2028 cmd |= ICE_TX_DESC_CMD_L4T_EOFT_TCP;
2029 l4_len = l4.tcp->doff;
2030 offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2031 break;
2032 case IPPROTO_UDP:
2033 /* enable UDP checksum offload */
2034 cmd |= ICE_TX_DESC_CMD_L4T_EOFT_UDP;
2035 l4_len = (sizeof(struct udphdr) >> 2);
2036 offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2037 break;
2038 case IPPROTO_SCTP:
2039 /* enable SCTP checksum offload */
2040 cmd |= ICE_TX_DESC_CMD_L4T_EOFT_SCTP;
2041 l4_len = sizeof(struct sctphdr) >> 2;
2042 offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2043 break;
2044
2045 default:
2046 if (first->tx_flags & ICE_TX_FLAGS_TSO)
2047 return -1;
2048 skb_checksum_help(skb);
2049 return 0;
2050 }
2051
2052 off->td_cmd |= cmd;
2053 off->td_offset |= offset;
2054 return 1;
2055 }
2056
2057 /**
2058 * ice_tx_prepare_vlan_flags - prepare generic Tx VLAN tagging flags for HW
2059 * @tx_ring: ring to send buffer on
2060 * @first: pointer to struct ice_tx_buf
2061 *
2062 * Checks the skb and set up correspondingly several generic transmit flags
2063 * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2064 */
2065 static void
ice_tx_prepare_vlan_flags(struct ice_ring * tx_ring,struct ice_tx_buf * first)2066 ice_tx_prepare_vlan_flags(struct ice_ring *tx_ring, struct ice_tx_buf *first)
2067 {
2068 struct sk_buff *skb = first->skb;
2069
2070 /* nothing left to do, software offloaded VLAN */
2071 if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
2072 return;
2073
2074 /* currently, we always assume 802.1Q for VLAN insertion as VLAN
2075 * insertion for 802.1AD is not supported
2076 */
2077 if (skb_vlan_tag_present(skb)) {
2078 first->tx_flags |= skb_vlan_tag_get(skb) << ICE_TX_FLAGS_VLAN_S;
2079 first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
2080 }
2081
2082 ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
2083 }
2084
2085 /**
2086 * ice_tso - computes mss and TSO length to prepare for TSO
2087 * @first: pointer to struct ice_tx_buf
2088 * @off: pointer to struct that holds offload parameters
2089 *
2090 * Returns 0 or error (negative) if TSO can't happen, 1 otherwise.
2091 */
2092 static
ice_tso(struct ice_tx_buf * first,struct ice_tx_offload_params * off)2093 int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2094 {
2095 struct sk_buff *skb = first->skb;
2096 union {
2097 struct iphdr *v4;
2098 struct ipv6hdr *v6;
2099 unsigned char *hdr;
2100 } ip;
2101 union {
2102 struct tcphdr *tcp;
2103 struct udphdr *udp;
2104 unsigned char *hdr;
2105 } l4;
2106 u64 cd_mss, cd_tso_len;
2107 u32 paylen;
2108 u8 l4_start;
2109 int err;
2110
2111 if (skb->ip_summed != CHECKSUM_PARTIAL)
2112 return 0;
2113
2114 if (!skb_is_gso(skb))
2115 return 0;
2116
2117 err = skb_cow_head(skb, 0);
2118 if (err < 0)
2119 return err;
2120
2121 /* cppcheck-suppress unreadVariable */
2122 ip.hdr = skb_network_header(skb);
2123 l4.hdr = skb_transport_header(skb);
2124
2125 /* initialize outer IP header fields */
2126 if (ip.v4->version == 4) {
2127 ip.v4->tot_len = 0;
2128 ip.v4->check = 0;
2129 } else {
2130 ip.v6->payload_len = 0;
2131 }
2132
2133 if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2134 SKB_GSO_GRE_CSUM |
2135 SKB_GSO_IPXIP4 |
2136 SKB_GSO_IPXIP6 |
2137 SKB_GSO_UDP_TUNNEL |
2138 SKB_GSO_UDP_TUNNEL_CSUM)) {
2139 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2140 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2141 l4.udp->len = 0;
2142
2143 /* determine offset of outer transport header */
2144 l4_start = (u8)(l4.hdr - skb->data);
2145
2146 /* remove payload length from outer checksum */
2147 paylen = skb->len - l4_start;
2148 csum_replace_by_diff(&l4.udp->check,
2149 (__force __wsum)htonl(paylen));
2150 }
2151
2152 /* reset pointers to inner headers */
2153
2154 /* cppcheck-suppress unreadVariable */
2155 ip.hdr = skb_inner_network_header(skb);
2156 l4.hdr = skb_inner_transport_header(skb);
2157
2158 /* initialize inner IP header fields */
2159 if (ip.v4->version == 4) {
2160 ip.v4->tot_len = 0;
2161 ip.v4->check = 0;
2162 } else {
2163 ip.v6->payload_len = 0;
2164 }
2165 }
2166
2167 /* determine offset of transport header */
2168 l4_start = (u8)(l4.hdr - skb->data);
2169
2170 /* remove payload length from checksum */
2171 paylen = skb->len - l4_start;
2172
2173 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
2174 csum_replace_by_diff(&l4.udp->check,
2175 (__force __wsum)htonl(paylen));
2176 /* compute length of UDP segmentation header */
2177 off->header_len = (u8)sizeof(l4.udp) + l4_start;
2178 } else {
2179 csum_replace_by_diff(&l4.tcp->check,
2180 (__force __wsum)htonl(paylen));
2181 /* compute length of TCP segmentation header */
2182 off->header_len = (u8)((l4.tcp->doff * 4) + l4_start);
2183 }
2184
2185 /* update gso_segs and bytecount */
2186 first->gso_segs = skb_shinfo(skb)->gso_segs;
2187 first->bytecount += (first->gso_segs - 1) * off->header_len;
2188
2189 cd_tso_len = skb->len - off->header_len;
2190 cd_mss = skb_shinfo(skb)->gso_size;
2191
2192 /* record cdesc_qw1 with TSO parameters */
2193 off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2194 (ICE_TX_CTX_DESC_TSO << ICE_TXD_CTX_QW1_CMD_S) |
2195 (cd_tso_len << ICE_TXD_CTX_QW1_TSO_LEN_S) |
2196 (cd_mss << ICE_TXD_CTX_QW1_MSS_S));
2197 first->tx_flags |= ICE_TX_FLAGS_TSO;
2198 return 1;
2199 }
2200
2201 /**
2202 * ice_txd_use_count - estimate the number of descriptors needed for Tx
2203 * @size: transmit request size in bytes
2204 *
2205 * Due to hardware alignment restrictions (4K alignment), we need to
2206 * assume that we can have no more than 12K of data per descriptor, even
2207 * though each descriptor can take up to 16K - 1 bytes of aligned memory.
2208 * Thus, we need to divide by 12K. But division is slow! Instead,
2209 * we decompose the operation into shifts and one relatively cheap
2210 * multiply operation.
2211 *
2212 * To divide by 12K, we first divide by 4K, then divide by 3:
2213 * To divide by 4K, shift right by 12 bits
2214 * To divide by 3, multiply by 85, then divide by 256
2215 * (Divide by 256 is done by shifting right by 8 bits)
2216 * Finally, we add one to round up. Because 256 isn't an exact multiple of
2217 * 3, we'll underestimate near each multiple of 12K. This is actually more
2218 * accurate as we have 4K - 1 of wiggle room that we can fit into the last
2219 * segment. For our purposes this is accurate out to 1M which is orders of
2220 * magnitude greater than our largest possible GSO size.
2221 *
2222 * This would then be implemented as:
2223 * return (((size >> 12) * 85) >> 8) + ICE_DESCS_FOR_SKB_DATA_PTR;
2224 *
2225 * Since multiplication and division are commutative, we can reorder
2226 * operations into:
2227 * return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2228 */
ice_txd_use_count(unsigned int size)2229 static unsigned int ice_txd_use_count(unsigned int size)
2230 {
2231 return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2232 }
2233
2234 /**
2235 * ice_xmit_desc_count - calculate number of Tx descriptors needed
2236 * @skb: send buffer
2237 *
2238 * Returns number of data descriptors needed for this skb.
2239 */
ice_xmit_desc_count(struct sk_buff * skb)2240 static unsigned int ice_xmit_desc_count(struct sk_buff *skb)
2241 {
2242 const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
2243 unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
2244 unsigned int count = 0, size = skb_headlen(skb);
2245
2246 for (;;) {
2247 count += ice_txd_use_count(size);
2248
2249 if (!nr_frags--)
2250 break;
2251
2252 size = skb_frag_size(frag++);
2253 }
2254
2255 return count;
2256 }
2257
2258 /**
2259 * __ice_chk_linearize - Check if there are more than 8 buffers per packet
2260 * @skb: send buffer
2261 *
2262 * Note: This HW can't DMA more than 8 buffers to build a packet on the wire
2263 * and so we need to figure out the cases where we need to linearize the skb.
2264 *
2265 * For TSO we need to count the TSO header and segment payload separately.
2266 * As such we need to check cases where we have 7 fragments or more as we
2267 * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2268 * the segment payload in the first descriptor, and another 7 for the
2269 * fragments.
2270 */
__ice_chk_linearize(struct sk_buff * skb)2271 static bool __ice_chk_linearize(struct sk_buff *skb)
2272 {
2273 const skb_frag_t *frag, *stale;
2274 int nr_frags, sum;
2275
2276 /* no need to check if number of frags is less than 7 */
2277 nr_frags = skb_shinfo(skb)->nr_frags;
2278 if (nr_frags < (ICE_MAX_BUF_TXD - 1))
2279 return false;
2280
2281 /* We need to walk through the list and validate that each group
2282 * of 6 fragments totals at least gso_size.
2283 */
2284 nr_frags -= ICE_MAX_BUF_TXD - 2;
2285 frag = &skb_shinfo(skb)->frags[0];
2286
2287 /* Initialize size to the negative value of gso_size minus 1. We
2288 * use this as the worst case scenario in which the frag ahead
2289 * of us only provides one byte which is why we are limited to 6
2290 * descriptors for a single transmit as the header and previous
2291 * fragment are already consuming 2 descriptors.
2292 */
2293 sum = 1 - skb_shinfo(skb)->gso_size;
2294
2295 /* Add size of frags 0 through 4 to create our initial sum */
2296 sum += skb_frag_size(frag++);
2297 sum += skb_frag_size(frag++);
2298 sum += skb_frag_size(frag++);
2299 sum += skb_frag_size(frag++);
2300 sum += skb_frag_size(frag++);
2301
2302 /* Walk through fragments adding latest fragment, testing it, and
2303 * then removing stale fragments from the sum.
2304 */
2305 for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
2306 int stale_size = skb_frag_size(stale);
2307
2308 sum += skb_frag_size(frag++);
2309
2310 /* The stale fragment may present us with a smaller
2311 * descriptor than the actual fragment size. To account
2312 * for that we need to remove all the data on the front and
2313 * figure out what the remainder would be in the last
2314 * descriptor associated with the fragment.
2315 */
2316 if (stale_size > ICE_MAX_DATA_PER_TXD) {
2317 int align_pad = -(skb_frag_off(stale)) &
2318 (ICE_MAX_READ_REQ_SIZE - 1);
2319
2320 sum -= align_pad;
2321 stale_size -= align_pad;
2322
2323 do {
2324 sum -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2325 stale_size -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2326 } while (stale_size > ICE_MAX_DATA_PER_TXD);
2327 }
2328
2329 /* if sum is negative we failed to make sufficient progress */
2330 if (sum < 0)
2331 return true;
2332
2333 if (!nr_frags--)
2334 break;
2335
2336 sum -= stale_size;
2337 }
2338
2339 return false;
2340 }
2341
2342 /**
2343 * ice_chk_linearize - Check if there are more than 8 fragments per packet
2344 * @skb: send buffer
2345 * @count: number of buffers used
2346 *
2347 * Note: Our HW can't scatter-gather more than 8 fragments to build
2348 * a packet on the wire and so we need to figure out the cases where we
2349 * need to linearize the skb.
2350 */
ice_chk_linearize(struct sk_buff * skb,unsigned int count)2351 static bool ice_chk_linearize(struct sk_buff *skb, unsigned int count)
2352 {
2353 /* Both TSO and single send will work if count is less than 8 */
2354 if (likely(count < ICE_MAX_BUF_TXD))
2355 return false;
2356
2357 if (skb_is_gso(skb))
2358 return __ice_chk_linearize(skb);
2359
2360 /* we can support up to 8 data buffers for a single send */
2361 return count != ICE_MAX_BUF_TXD;
2362 }
2363
2364 /**
2365 * ice_xmit_frame_ring - Sends buffer on Tx ring
2366 * @skb: send buffer
2367 * @tx_ring: ring to send buffer on
2368 *
2369 * Returns NETDEV_TX_OK if sent, else an error code
2370 */
2371 static netdev_tx_t
ice_xmit_frame_ring(struct sk_buff * skb,struct ice_ring * tx_ring)2372 ice_xmit_frame_ring(struct sk_buff *skb, struct ice_ring *tx_ring)
2373 {
2374 struct ice_tx_offload_params offload = { 0 };
2375 struct ice_vsi *vsi = tx_ring->vsi;
2376 struct ice_tx_buf *first;
2377 struct ethhdr *eth;
2378 unsigned int count;
2379 int tso, csum;
2380
2381 count = ice_xmit_desc_count(skb);
2382 if (ice_chk_linearize(skb, count)) {
2383 if (__skb_linearize(skb))
2384 goto out_drop;
2385 count = ice_txd_use_count(skb->len);
2386 tx_ring->tx_stats.tx_linearize++;
2387 }
2388
2389 /* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
2390 * + 1 desc for skb_head_len/ICE_MAX_DATA_PER_TXD,
2391 * + 4 desc gap to avoid the cache line where head is,
2392 * + 1 desc for context descriptor,
2393 * otherwise try next time
2394 */
2395 if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
2396 ICE_DESCS_FOR_CTX_DESC)) {
2397 tx_ring->tx_stats.tx_busy++;
2398 return NETDEV_TX_BUSY;
2399 }
2400
2401 offload.tx_ring = tx_ring;
2402
2403 /* record the location of the first descriptor for this packet */
2404 first = &tx_ring->tx_buf[tx_ring->next_to_use];
2405 first->skb = skb;
2406 first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
2407 first->gso_segs = 1;
2408 first->tx_flags = 0;
2409
2410 /* prepare the VLAN tagging flags for Tx */
2411 ice_tx_prepare_vlan_flags(tx_ring, first);
2412
2413 /* set up TSO offload */
2414 tso = ice_tso(first, &offload);
2415 if (tso < 0)
2416 goto out_drop;
2417
2418 /* always set up Tx checksum offload */
2419 csum = ice_tx_csum(first, &offload);
2420 if (csum < 0)
2421 goto out_drop;
2422
2423 /* allow CONTROL frames egress from main VSI if FW LLDP disabled */
2424 eth = (struct ethhdr *)skb_mac_header(skb);
2425 if (unlikely((skb->priority == TC_PRIO_CONTROL ||
2426 eth->h_proto == htons(ETH_P_LLDP)) &&
2427 vsi->type == ICE_VSI_PF &&
2428 vsi->port_info->qos_cfg.is_sw_lldp))
2429 offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2430 ICE_TX_CTX_DESC_SWTCH_UPLINK <<
2431 ICE_TXD_CTX_QW1_CMD_S);
2432
2433 if (offload.cd_qw1 & ICE_TX_DESC_DTYPE_CTX) {
2434 struct ice_tx_ctx_desc *cdesc;
2435 u16 i = tx_ring->next_to_use;
2436
2437 /* grab the next descriptor */
2438 cdesc = ICE_TX_CTX_DESC(tx_ring, i);
2439 i++;
2440 tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2441
2442 /* setup context descriptor */
2443 cdesc->tunneling_params = cpu_to_le32(offload.cd_tunnel_params);
2444 cdesc->l2tag2 = cpu_to_le16(offload.cd_l2tag2);
2445 cdesc->rsvd = cpu_to_le16(0);
2446 cdesc->qw1 = cpu_to_le64(offload.cd_qw1);
2447 }
2448
2449 ice_tx_map(tx_ring, first, &offload);
2450 return NETDEV_TX_OK;
2451
2452 out_drop:
2453 dev_kfree_skb_any(skb);
2454 return NETDEV_TX_OK;
2455 }
2456
2457 /**
2458 * ice_start_xmit - Selects the correct VSI and Tx queue to send buffer
2459 * @skb: send buffer
2460 * @netdev: network interface device structure
2461 *
2462 * Returns NETDEV_TX_OK if sent, else an error code
2463 */
ice_start_xmit(struct sk_buff * skb,struct net_device * netdev)2464 netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev)
2465 {
2466 struct ice_netdev_priv *np = netdev_priv(netdev);
2467 struct ice_vsi *vsi = np->vsi;
2468 struct ice_ring *tx_ring;
2469
2470 tx_ring = vsi->tx_rings[skb->queue_mapping];
2471
2472 /* hardware can't handle really short frames, hardware padding works
2473 * beyond this point
2474 */
2475 if (skb_put_padto(skb, ICE_MIN_TX_LEN))
2476 return NETDEV_TX_OK;
2477
2478 return ice_xmit_frame_ring(skb, tx_ring);
2479 }
2480
2481 /**
2482 * ice_clean_ctrl_tx_irq - interrupt handler for flow director Tx queue
2483 * @tx_ring: tx_ring to clean
2484 */
ice_clean_ctrl_tx_irq(struct ice_ring * tx_ring)2485 void ice_clean_ctrl_tx_irq(struct ice_ring *tx_ring)
2486 {
2487 struct ice_vsi *vsi = tx_ring->vsi;
2488 s16 i = tx_ring->next_to_clean;
2489 int budget = ICE_DFLT_IRQ_WORK;
2490 struct ice_tx_desc *tx_desc;
2491 struct ice_tx_buf *tx_buf;
2492
2493 tx_buf = &tx_ring->tx_buf[i];
2494 tx_desc = ICE_TX_DESC(tx_ring, i);
2495 i -= tx_ring->count;
2496
2497 do {
2498 struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
2499
2500 /* if next_to_watch is not set then there is no pending work */
2501 if (!eop_desc)
2502 break;
2503
2504 /* prevent any other reads prior to eop_desc */
2505 smp_rmb();
2506
2507 /* if the descriptor isn't done, no work to do */
2508 if (!(eop_desc->cmd_type_offset_bsz &
2509 cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
2510 break;
2511
2512 /* clear next_to_watch to prevent false hangs */
2513 tx_buf->next_to_watch = NULL;
2514 tx_desc->buf_addr = 0;
2515 tx_desc->cmd_type_offset_bsz = 0;
2516
2517 /* move past filter desc */
2518 tx_buf++;
2519 tx_desc++;
2520 i++;
2521 if (unlikely(!i)) {
2522 i -= tx_ring->count;
2523 tx_buf = tx_ring->tx_buf;
2524 tx_desc = ICE_TX_DESC(tx_ring, 0);
2525 }
2526
2527 /* unmap the data header */
2528 if (dma_unmap_len(tx_buf, len))
2529 dma_unmap_single(tx_ring->dev,
2530 dma_unmap_addr(tx_buf, dma),
2531 dma_unmap_len(tx_buf, len),
2532 DMA_TO_DEVICE);
2533 if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
2534 devm_kfree(tx_ring->dev, tx_buf->raw_buf);
2535
2536 /* clear next_to_watch to prevent false hangs */
2537 tx_buf->raw_buf = NULL;
2538 tx_buf->tx_flags = 0;
2539 tx_buf->next_to_watch = NULL;
2540 dma_unmap_len_set(tx_buf, len, 0);
2541 tx_desc->buf_addr = 0;
2542 tx_desc->cmd_type_offset_bsz = 0;
2543
2544 /* move past eop_desc for start of next FD desc */
2545 tx_buf++;
2546 tx_desc++;
2547 i++;
2548 if (unlikely(!i)) {
2549 i -= tx_ring->count;
2550 tx_buf = tx_ring->tx_buf;
2551 tx_desc = ICE_TX_DESC(tx_ring, 0);
2552 }
2553
2554 budget--;
2555 } while (likely(budget));
2556
2557 i += tx_ring->count;
2558 tx_ring->next_to_clean = i;
2559
2560 /* re-enable interrupt if needed */
2561 ice_irq_dynamic_ena(&vsi->back->hw, vsi, vsi->q_vectors[0]);
2562 }
2563