1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3 * Driver for Solarflare network controllers and boards
4 * Copyright 2005-2006 Fen Systems Ltd.
5 * Copyright 2005-2013 Solarflare Communications Inc.
6 */
7
8 #include <linux/socket.h>
9 #include <linux/in.h>
10 #include <linux/slab.h>
11 #include <linux/ip.h>
12 #include <linux/ipv6.h>
13 #include <linux/tcp.h>
14 #include <linux/udp.h>
15 #include <linux/prefetch.h>
16 #include <linux/moduleparam.h>
17 #include <linux/iommu.h>
18 #include <net/ip.h>
19 #include <net/checksum.h>
20 #include "net_driver.h"
21 #include "efx.h"
22 #include "filter.h"
23 #include "nic.h"
24 #include "selftest.h"
25 #include "workarounds.h"
26
27 /* Preferred number of descriptors to fill at once */
28 #define EF4_RX_PREFERRED_BATCH 8U
29
30 /* Number of RX buffers to recycle pages for. When creating the RX page recycle
31 * ring, this number is divided by the number of buffers per page to calculate
32 * the number of pages to store in the RX page recycle ring.
33 */
34 #define EF4_RECYCLE_RING_SIZE_IOMMU 4096
35 #define EF4_RECYCLE_RING_SIZE_NOIOMMU (2 * EF4_RX_PREFERRED_BATCH)
36
37 /* Size of buffer allocated for skb header area. */
38 #define EF4_SKB_HEADERS 128u
39
40 /* This is the percentage fill level below which new RX descriptors
41 * will be added to the RX descriptor ring.
42 */
43 static unsigned int rx_refill_threshold;
44
45 /* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
46 #define EF4_RX_MAX_FRAGS DIV_ROUND_UP(EF4_MAX_FRAME_LEN(EF4_MAX_MTU), \
47 EF4_RX_USR_BUF_SIZE)
48
49 /*
50 * RX maximum head room required.
51 *
52 * This must be at least 1 to prevent overflow, plus one packet-worth
53 * to allow pipelined receives.
54 */
55 #define EF4_RXD_HEAD_ROOM (1 + EF4_RX_MAX_FRAGS)
56
ef4_rx_buf_va(struct ef4_rx_buffer * buf)57 static inline u8 *ef4_rx_buf_va(struct ef4_rx_buffer *buf)
58 {
59 return page_address(buf->page) + buf->page_offset;
60 }
61
ef4_rx_buf_hash(struct ef4_nic * efx,const u8 * eh)62 static inline u32 ef4_rx_buf_hash(struct ef4_nic *efx, const u8 *eh)
63 {
64 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
65 return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_hash_offset));
66 #else
67 const u8 *data = eh + efx->rx_packet_hash_offset;
68 return (u32)data[0] |
69 (u32)data[1] << 8 |
70 (u32)data[2] << 16 |
71 (u32)data[3] << 24;
72 #endif
73 }
74
75 static inline struct ef4_rx_buffer *
ef4_rx_buf_next(struct ef4_rx_queue * rx_queue,struct ef4_rx_buffer * rx_buf)76 ef4_rx_buf_next(struct ef4_rx_queue *rx_queue, struct ef4_rx_buffer *rx_buf)
77 {
78 if (unlikely(rx_buf == ef4_rx_buffer(rx_queue, rx_queue->ptr_mask)))
79 return ef4_rx_buffer(rx_queue, 0);
80 else
81 return rx_buf + 1;
82 }
83
ef4_sync_rx_buffer(struct ef4_nic * efx,struct ef4_rx_buffer * rx_buf,unsigned int len)84 static inline void ef4_sync_rx_buffer(struct ef4_nic *efx,
85 struct ef4_rx_buffer *rx_buf,
86 unsigned int len)
87 {
88 dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len,
89 DMA_FROM_DEVICE);
90 }
91
ef4_rx_config_page_split(struct ef4_nic * efx)92 void ef4_rx_config_page_split(struct ef4_nic *efx)
93 {
94 efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align,
95 EF4_RX_BUF_ALIGNMENT);
96 efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
97 ((PAGE_SIZE - sizeof(struct ef4_rx_page_state)) /
98 efx->rx_page_buf_step);
99 efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
100 efx->rx_bufs_per_page;
101 efx->rx_pages_per_batch = DIV_ROUND_UP(EF4_RX_PREFERRED_BATCH,
102 efx->rx_bufs_per_page);
103 }
104
105 /* Check the RX page recycle ring for a page that can be reused. */
ef4_reuse_page(struct ef4_rx_queue * rx_queue)106 static struct page *ef4_reuse_page(struct ef4_rx_queue *rx_queue)
107 {
108 struct ef4_nic *efx = rx_queue->efx;
109 struct page *page;
110 struct ef4_rx_page_state *state;
111 unsigned index;
112
113 if (unlikely(!rx_queue->page_ring))
114 return NULL;
115 index = rx_queue->page_remove & rx_queue->page_ptr_mask;
116 page = rx_queue->page_ring[index];
117 if (page == NULL)
118 return NULL;
119
120 rx_queue->page_ring[index] = NULL;
121 /* page_remove cannot exceed page_add. */
122 if (rx_queue->page_remove != rx_queue->page_add)
123 ++rx_queue->page_remove;
124
125 /* If page_count is 1 then we hold the only reference to this page. */
126 if (page_count(page) == 1) {
127 ++rx_queue->page_recycle_count;
128 return page;
129 } else {
130 state = page_address(page);
131 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
132 PAGE_SIZE << efx->rx_buffer_order,
133 DMA_FROM_DEVICE);
134 put_page(page);
135 ++rx_queue->page_recycle_failed;
136 }
137
138 return NULL;
139 }
140
141 /**
142 * ef4_init_rx_buffers - create EF4_RX_BATCH page-based RX buffers
143 *
144 * @rx_queue: Efx RX queue
145 * @atomic: control memory allocation flags
146 *
147 * This allocates a batch of pages, maps them for DMA, and populates
148 * struct ef4_rx_buffers for each one. Return a negative error code or
149 * 0 on success. If a single page can be used for multiple buffers,
150 * then the page will either be inserted fully, or not at all.
151 */
ef4_init_rx_buffers(struct ef4_rx_queue * rx_queue,bool atomic)152 static int ef4_init_rx_buffers(struct ef4_rx_queue *rx_queue, bool atomic)
153 {
154 struct ef4_nic *efx = rx_queue->efx;
155 struct ef4_rx_buffer *rx_buf;
156 struct page *page;
157 unsigned int page_offset;
158 struct ef4_rx_page_state *state;
159 dma_addr_t dma_addr;
160 unsigned index, count;
161
162 count = 0;
163 do {
164 page = ef4_reuse_page(rx_queue);
165 if (page == NULL) {
166 page = alloc_pages(__GFP_COMP |
167 (atomic ? GFP_ATOMIC : GFP_KERNEL),
168 efx->rx_buffer_order);
169 if (unlikely(page == NULL))
170 return -ENOMEM;
171 dma_addr =
172 dma_map_page(&efx->pci_dev->dev, page, 0,
173 PAGE_SIZE << efx->rx_buffer_order,
174 DMA_FROM_DEVICE);
175 if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
176 dma_addr))) {
177 __free_pages(page, efx->rx_buffer_order);
178 return -EIO;
179 }
180 state = page_address(page);
181 state->dma_addr = dma_addr;
182 } else {
183 state = page_address(page);
184 dma_addr = state->dma_addr;
185 }
186
187 dma_addr += sizeof(struct ef4_rx_page_state);
188 page_offset = sizeof(struct ef4_rx_page_state);
189
190 do {
191 index = rx_queue->added_count & rx_queue->ptr_mask;
192 rx_buf = ef4_rx_buffer(rx_queue, index);
193 rx_buf->dma_addr = dma_addr + efx->rx_ip_align;
194 rx_buf->page = page;
195 rx_buf->page_offset = page_offset + efx->rx_ip_align;
196 rx_buf->len = efx->rx_dma_len;
197 rx_buf->flags = 0;
198 ++rx_queue->added_count;
199 get_page(page);
200 dma_addr += efx->rx_page_buf_step;
201 page_offset += efx->rx_page_buf_step;
202 } while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE);
203
204 rx_buf->flags = EF4_RX_BUF_LAST_IN_PAGE;
205 } while (++count < efx->rx_pages_per_batch);
206
207 return 0;
208 }
209
210 /* Unmap a DMA-mapped page. This function is only called for the final RX
211 * buffer in a page.
212 */
ef4_unmap_rx_buffer(struct ef4_nic * efx,struct ef4_rx_buffer * rx_buf)213 static void ef4_unmap_rx_buffer(struct ef4_nic *efx,
214 struct ef4_rx_buffer *rx_buf)
215 {
216 struct page *page = rx_buf->page;
217
218 if (page) {
219 struct ef4_rx_page_state *state = page_address(page);
220 dma_unmap_page(&efx->pci_dev->dev,
221 state->dma_addr,
222 PAGE_SIZE << efx->rx_buffer_order,
223 DMA_FROM_DEVICE);
224 }
225 }
226
ef4_free_rx_buffers(struct ef4_rx_queue * rx_queue,struct ef4_rx_buffer * rx_buf,unsigned int num_bufs)227 static void ef4_free_rx_buffers(struct ef4_rx_queue *rx_queue,
228 struct ef4_rx_buffer *rx_buf,
229 unsigned int num_bufs)
230 {
231 do {
232 if (rx_buf->page) {
233 put_page(rx_buf->page);
234 rx_buf->page = NULL;
235 }
236 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
237 } while (--num_bufs);
238 }
239
240 /* Attempt to recycle the page if there is an RX recycle ring; the page can
241 * only be added if this is the final RX buffer, to prevent pages being used in
242 * the descriptor ring and appearing in the recycle ring simultaneously.
243 */
ef4_recycle_rx_page(struct ef4_channel * channel,struct ef4_rx_buffer * rx_buf)244 static void ef4_recycle_rx_page(struct ef4_channel *channel,
245 struct ef4_rx_buffer *rx_buf)
246 {
247 struct page *page = rx_buf->page;
248 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
249 struct ef4_nic *efx = rx_queue->efx;
250 unsigned index;
251
252 /* Only recycle the page after processing the final buffer. */
253 if (!(rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE))
254 return;
255
256 index = rx_queue->page_add & rx_queue->page_ptr_mask;
257 if (rx_queue->page_ring[index] == NULL) {
258 unsigned read_index = rx_queue->page_remove &
259 rx_queue->page_ptr_mask;
260
261 /* The next slot in the recycle ring is available, but
262 * increment page_remove if the read pointer currently
263 * points here.
264 */
265 if (read_index == index)
266 ++rx_queue->page_remove;
267 rx_queue->page_ring[index] = page;
268 ++rx_queue->page_add;
269 return;
270 }
271 ++rx_queue->page_recycle_full;
272 ef4_unmap_rx_buffer(efx, rx_buf);
273 put_page(rx_buf->page);
274 }
275
ef4_fini_rx_buffer(struct ef4_rx_queue * rx_queue,struct ef4_rx_buffer * rx_buf)276 static void ef4_fini_rx_buffer(struct ef4_rx_queue *rx_queue,
277 struct ef4_rx_buffer *rx_buf)
278 {
279 /* Release the page reference we hold for the buffer. */
280 if (rx_buf->page)
281 put_page(rx_buf->page);
282
283 /* If this is the last buffer in a page, unmap and free it. */
284 if (rx_buf->flags & EF4_RX_BUF_LAST_IN_PAGE) {
285 ef4_unmap_rx_buffer(rx_queue->efx, rx_buf);
286 ef4_free_rx_buffers(rx_queue, rx_buf, 1);
287 }
288 rx_buf->page = NULL;
289 }
290
291 /* Recycle the pages that are used by buffers that have just been received. */
ef4_recycle_rx_pages(struct ef4_channel * channel,struct ef4_rx_buffer * rx_buf,unsigned int n_frags)292 static void ef4_recycle_rx_pages(struct ef4_channel *channel,
293 struct ef4_rx_buffer *rx_buf,
294 unsigned int n_frags)
295 {
296 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
297
298 if (unlikely(!rx_queue->page_ring))
299 return;
300
301 do {
302 ef4_recycle_rx_page(channel, rx_buf);
303 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
304 } while (--n_frags);
305 }
306
ef4_discard_rx_packet(struct ef4_channel * channel,struct ef4_rx_buffer * rx_buf,unsigned int n_frags)307 static void ef4_discard_rx_packet(struct ef4_channel *channel,
308 struct ef4_rx_buffer *rx_buf,
309 unsigned int n_frags)
310 {
311 struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel);
312
313 ef4_recycle_rx_pages(channel, rx_buf, n_frags);
314
315 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
316 }
317
318 /**
319 * ef4_fast_push_rx_descriptors - push new RX descriptors quickly
320 * @rx_queue: RX descriptor queue
321 *
322 * This will aim to fill the RX descriptor queue up to
323 * @rx_queue->@max_fill. If there is insufficient atomic
324 * memory to do so, a slow fill will be scheduled.
325 * @atomic: control memory allocation flags
326 *
327 * The caller must provide serialisation (none is used here). In practise,
328 * this means this function must run from the NAPI handler, or be called
329 * when NAPI is disabled.
330 */
ef4_fast_push_rx_descriptors(struct ef4_rx_queue * rx_queue,bool atomic)331 void ef4_fast_push_rx_descriptors(struct ef4_rx_queue *rx_queue, bool atomic)
332 {
333 struct ef4_nic *efx = rx_queue->efx;
334 unsigned int fill_level, batch_size;
335 int space, rc = 0;
336
337 if (!rx_queue->refill_enabled)
338 return;
339
340 /* Calculate current fill level, and exit if we don't need to fill */
341 fill_level = (rx_queue->added_count - rx_queue->removed_count);
342 EF4_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
343 if (fill_level >= rx_queue->fast_fill_trigger)
344 goto out;
345
346 /* Record minimum fill level */
347 if (unlikely(fill_level < rx_queue->min_fill)) {
348 if (fill_level)
349 rx_queue->min_fill = fill_level;
350 }
351
352 batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
353 space = rx_queue->max_fill - fill_level;
354 EF4_BUG_ON_PARANOID(space < batch_size);
355
356 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
357 "RX queue %d fast-filling descriptor ring from"
358 " level %d to level %d\n",
359 ef4_rx_queue_index(rx_queue), fill_level,
360 rx_queue->max_fill);
361
362
363 do {
364 rc = ef4_init_rx_buffers(rx_queue, atomic);
365 if (unlikely(rc)) {
366 /* Ensure that we don't leave the rx queue empty */
367 if (rx_queue->added_count == rx_queue->removed_count)
368 ef4_schedule_slow_fill(rx_queue);
369 goto out;
370 }
371 } while ((space -= batch_size) >= batch_size);
372
373 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
374 "RX queue %d fast-filled descriptor ring "
375 "to level %d\n", ef4_rx_queue_index(rx_queue),
376 rx_queue->added_count - rx_queue->removed_count);
377
378 out:
379 if (rx_queue->notified_count != rx_queue->added_count)
380 ef4_nic_notify_rx_desc(rx_queue);
381 }
382
ef4_rx_slow_fill(struct timer_list * t)383 void ef4_rx_slow_fill(struct timer_list *t)
384 {
385 struct ef4_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);
386
387 /* Post an event to cause NAPI to run and refill the queue */
388 ef4_nic_generate_fill_event(rx_queue);
389 ++rx_queue->slow_fill_count;
390 }
391
ef4_rx_packet__check_len(struct ef4_rx_queue * rx_queue,struct ef4_rx_buffer * rx_buf,int len)392 static void ef4_rx_packet__check_len(struct ef4_rx_queue *rx_queue,
393 struct ef4_rx_buffer *rx_buf,
394 int len)
395 {
396 struct ef4_nic *efx = rx_queue->efx;
397 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
398
399 if (likely(len <= max_len))
400 return;
401
402 /* The packet must be discarded, but this is only a fatal error
403 * if the caller indicated it was
404 */
405 rx_buf->flags |= EF4_RX_PKT_DISCARD;
406
407 if ((len > rx_buf->len) && EF4_WORKAROUND_8071(efx)) {
408 if (net_ratelimit())
409 netif_err(efx, rx_err, efx->net_dev,
410 " RX queue %d seriously overlength "
411 "RX event (0x%x > 0x%x+0x%x). Leaking\n",
412 ef4_rx_queue_index(rx_queue), len, max_len,
413 efx->type->rx_buffer_padding);
414 ef4_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
415 } else {
416 if (net_ratelimit())
417 netif_err(efx, rx_err, efx->net_dev,
418 " RX queue %d overlength RX event "
419 "(0x%x > 0x%x)\n",
420 ef4_rx_queue_index(rx_queue), len, max_len);
421 }
422
423 ef4_rx_queue_channel(rx_queue)->n_rx_overlength++;
424 }
425
426 /* Pass a received packet up through GRO. GRO can handle pages
427 * regardless of checksum state and skbs with a good checksum.
428 */
429 static void
ef4_rx_packet_gro(struct ef4_channel * channel,struct ef4_rx_buffer * rx_buf,unsigned int n_frags,u8 * eh)430 ef4_rx_packet_gro(struct ef4_channel *channel, struct ef4_rx_buffer *rx_buf,
431 unsigned int n_frags, u8 *eh)
432 {
433 struct napi_struct *napi = &channel->napi_str;
434 struct ef4_nic *efx = channel->efx;
435 struct sk_buff *skb;
436
437 skb = napi_get_frags(napi);
438 if (unlikely(!skb)) {
439 struct ef4_rx_queue *rx_queue;
440
441 rx_queue = ef4_channel_get_rx_queue(channel);
442 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
443 return;
444 }
445
446 if (efx->net_dev->features & NETIF_F_RXHASH)
447 skb_set_hash(skb, ef4_rx_buf_hash(efx, eh),
448 PKT_HASH_TYPE_L3);
449 skb->ip_summed = ((rx_buf->flags & EF4_RX_PKT_CSUMMED) ?
450 CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
451
452 for (;;) {
453 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
454 rx_buf->page, rx_buf->page_offset,
455 rx_buf->len);
456 rx_buf->page = NULL;
457 skb->len += rx_buf->len;
458 if (skb_shinfo(skb)->nr_frags == n_frags)
459 break;
460
461 rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
462 }
463
464 skb->data_len = skb->len;
465 skb->truesize += n_frags * efx->rx_buffer_truesize;
466
467 skb_record_rx_queue(skb, channel->rx_queue.core_index);
468
469 napi_gro_frags(napi);
470 }
471
472 /* Allocate and construct an SKB around page fragments */
ef4_rx_mk_skb(struct ef4_channel * channel,struct ef4_rx_buffer * rx_buf,unsigned int n_frags,u8 * eh,int hdr_len)473 static struct sk_buff *ef4_rx_mk_skb(struct ef4_channel *channel,
474 struct ef4_rx_buffer *rx_buf,
475 unsigned int n_frags,
476 u8 *eh, int hdr_len)
477 {
478 struct ef4_nic *efx = channel->efx;
479 struct sk_buff *skb;
480
481 /* Allocate an SKB to store the headers */
482 skb = netdev_alloc_skb(efx->net_dev,
483 efx->rx_ip_align + efx->rx_prefix_size +
484 hdr_len);
485 if (unlikely(skb == NULL)) {
486 atomic_inc(&efx->n_rx_noskb_drops);
487 return NULL;
488 }
489
490 EF4_BUG_ON_PARANOID(rx_buf->len < hdr_len);
491
492 memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
493 efx->rx_prefix_size + hdr_len);
494 skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
495 __skb_put(skb, hdr_len);
496
497 /* Append the remaining page(s) onto the frag list */
498 if (rx_buf->len > hdr_len) {
499 rx_buf->page_offset += hdr_len;
500 rx_buf->len -= hdr_len;
501
502 for (;;) {
503 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
504 rx_buf->page, rx_buf->page_offset,
505 rx_buf->len);
506 rx_buf->page = NULL;
507 skb->len += rx_buf->len;
508 skb->data_len += rx_buf->len;
509 if (skb_shinfo(skb)->nr_frags == n_frags)
510 break;
511
512 rx_buf = ef4_rx_buf_next(&channel->rx_queue, rx_buf);
513 }
514 } else {
515 __free_pages(rx_buf->page, efx->rx_buffer_order);
516 rx_buf->page = NULL;
517 n_frags = 0;
518 }
519
520 skb->truesize += n_frags * efx->rx_buffer_truesize;
521
522 /* Move past the ethernet header */
523 skb->protocol = eth_type_trans(skb, efx->net_dev);
524
525 skb_mark_napi_id(skb, &channel->napi_str);
526
527 return skb;
528 }
529
ef4_rx_packet(struct ef4_rx_queue * rx_queue,unsigned int index,unsigned int n_frags,unsigned int len,u16 flags)530 void ef4_rx_packet(struct ef4_rx_queue *rx_queue, unsigned int index,
531 unsigned int n_frags, unsigned int len, u16 flags)
532 {
533 struct ef4_nic *efx = rx_queue->efx;
534 struct ef4_channel *channel = ef4_rx_queue_channel(rx_queue);
535 struct ef4_rx_buffer *rx_buf;
536
537 rx_queue->rx_packets++;
538
539 rx_buf = ef4_rx_buffer(rx_queue, index);
540 rx_buf->flags |= flags;
541
542 /* Validate the number of fragments and completed length */
543 if (n_frags == 1) {
544 if (!(flags & EF4_RX_PKT_PREFIX_LEN))
545 ef4_rx_packet__check_len(rx_queue, rx_buf, len);
546 } else if (unlikely(n_frags > EF4_RX_MAX_FRAGS) ||
547 unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
548 unlikely(len > n_frags * efx->rx_dma_len) ||
549 unlikely(!efx->rx_scatter)) {
550 /* If this isn't an explicit discard request, either
551 * the hardware or the driver is broken.
552 */
553 WARN_ON(!(len == 0 && rx_buf->flags & EF4_RX_PKT_DISCARD));
554 rx_buf->flags |= EF4_RX_PKT_DISCARD;
555 }
556
557 netif_vdbg(efx, rx_status, efx->net_dev,
558 "RX queue %d received ids %x-%x len %d %s%s\n",
559 ef4_rx_queue_index(rx_queue), index,
560 (index + n_frags - 1) & rx_queue->ptr_mask, len,
561 (rx_buf->flags & EF4_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
562 (rx_buf->flags & EF4_RX_PKT_DISCARD) ? " [DISCARD]" : "");
563
564 /* Discard packet, if instructed to do so. Process the
565 * previous receive first.
566 */
567 if (unlikely(rx_buf->flags & EF4_RX_PKT_DISCARD)) {
568 ef4_rx_flush_packet(channel);
569 ef4_discard_rx_packet(channel, rx_buf, n_frags);
570 return;
571 }
572
573 if (n_frags == 1 && !(flags & EF4_RX_PKT_PREFIX_LEN))
574 rx_buf->len = len;
575
576 /* Release and/or sync the DMA mapping - assumes all RX buffers
577 * consumed in-order per RX queue.
578 */
579 ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
580
581 /* Prefetch nice and early so data will (hopefully) be in cache by
582 * the time we look at it.
583 */
584 prefetch(ef4_rx_buf_va(rx_buf));
585
586 rx_buf->page_offset += efx->rx_prefix_size;
587 rx_buf->len -= efx->rx_prefix_size;
588
589 if (n_frags > 1) {
590 /* Release/sync DMA mapping for additional fragments.
591 * Fix length for last fragment.
592 */
593 unsigned int tail_frags = n_frags - 1;
594
595 for (;;) {
596 rx_buf = ef4_rx_buf_next(rx_queue, rx_buf);
597 if (--tail_frags == 0)
598 break;
599 ef4_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
600 }
601 rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
602 ef4_sync_rx_buffer(efx, rx_buf, rx_buf->len);
603 }
604
605 /* All fragments have been DMA-synced, so recycle pages. */
606 rx_buf = ef4_rx_buffer(rx_queue, index);
607 ef4_recycle_rx_pages(channel, rx_buf, n_frags);
608
609 /* Pipeline receives so that we give time for packet headers to be
610 * prefetched into cache.
611 */
612 ef4_rx_flush_packet(channel);
613 channel->rx_pkt_n_frags = n_frags;
614 channel->rx_pkt_index = index;
615 }
616
ef4_rx_deliver(struct ef4_channel * channel,u8 * eh,struct ef4_rx_buffer * rx_buf,unsigned int n_frags)617 static void ef4_rx_deliver(struct ef4_channel *channel, u8 *eh,
618 struct ef4_rx_buffer *rx_buf,
619 unsigned int n_frags)
620 {
621 struct sk_buff *skb;
622 u16 hdr_len = min_t(u16, rx_buf->len, EF4_SKB_HEADERS);
623
624 skb = ef4_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
625 if (unlikely(skb == NULL)) {
626 struct ef4_rx_queue *rx_queue;
627
628 rx_queue = ef4_channel_get_rx_queue(channel);
629 ef4_free_rx_buffers(rx_queue, rx_buf, n_frags);
630 return;
631 }
632 skb_record_rx_queue(skb, channel->rx_queue.core_index);
633
634 /* Set the SKB flags */
635 skb_checksum_none_assert(skb);
636 if (likely(rx_buf->flags & EF4_RX_PKT_CSUMMED))
637 skb->ip_summed = CHECKSUM_UNNECESSARY;
638
639 if (channel->type->receive_skb)
640 if (channel->type->receive_skb(channel, skb))
641 return;
642
643 /* Pass the packet up */
644 netif_receive_skb(skb);
645 }
646
647 /* Handle a received packet. Second half: Touches packet payload. */
__ef4_rx_packet(struct ef4_channel * channel)648 void __ef4_rx_packet(struct ef4_channel *channel)
649 {
650 struct ef4_nic *efx = channel->efx;
651 struct ef4_rx_buffer *rx_buf =
652 ef4_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
653 u8 *eh = ef4_rx_buf_va(rx_buf);
654
655 /* Read length from the prefix if necessary. This already
656 * excludes the length of the prefix itself.
657 */
658 if (rx_buf->flags & EF4_RX_PKT_PREFIX_LEN)
659 rx_buf->len = le16_to_cpup((__le16 *)
660 (eh + efx->rx_packet_len_offset));
661
662 /* If we're in loopback test, then pass the packet directly to the
663 * loopback layer, and free the rx_buf here
664 */
665 if (unlikely(efx->loopback_selftest)) {
666 struct ef4_rx_queue *rx_queue;
667
668 ef4_loopback_rx_packet(efx, eh, rx_buf->len);
669 rx_queue = ef4_channel_get_rx_queue(channel);
670 ef4_free_rx_buffers(rx_queue, rx_buf,
671 channel->rx_pkt_n_frags);
672 goto out;
673 }
674
675 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
676 rx_buf->flags &= ~EF4_RX_PKT_CSUMMED;
677
678 if ((rx_buf->flags & EF4_RX_PKT_TCP) && !channel->type->receive_skb)
679 ef4_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
680 else
681 ef4_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
682 out:
683 channel->rx_pkt_n_frags = 0;
684 }
685
ef4_probe_rx_queue(struct ef4_rx_queue * rx_queue)686 int ef4_probe_rx_queue(struct ef4_rx_queue *rx_queue)
687 {
688 struct ef4_nic *efx = rx_queue->efx;
689 unsigned int entries;
690 int rc;
691
692 /* Create the smallest power-of-two aligned ring */
693 entries = max(roundup_pow_of_two(efx->rxq_entries), EF4_MIN_DMAQ_SIZE);
694 EF4_BUG_ON_PARANOID(entries > EF4_MAX_DMAQ_SIZE);
695 rx_queue->ptr_mask = entries - 1;
696
697 netif_dbg(efx, probe, efx->net_dev,
698 "creating RX queue %d size %#x mask %#x\n",
699 ef4_rx_queue_index(rx_queue), efx->rxq_entries,
700 rx_queue->ptr_mask);
701
702 /* Allocate RX buffers */
703 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
704 GFP_KERNEL);
705 if (!rx_queue->buffer)
706 return -ENOMEM;
707
708 rc = ef4_nic_probe_rx(rx_queue);
709 if (rc) {
710 kfree(rx_queue->buffer);
711 rx_queue->buffer = NULL;
712 }
713
714 return rc;
715 }
716
ef4_init_rx_recycle_ring(struct ef4_nic * efx,struct ef4_rx_queue * rx_queue)717 static void ef4_init_rx_recycle_ring(struct ef4_nic *efx,
718 struct ef4_rx_queue *rx_queue)
719 {
720 unsigned int bufs_in_recycle_ring, page_ring_size;
721 struct iommu_domain __maybe_unused *domain;
722
723 /* Set the RX recycle ring size */
724 #ifdef CONFIG_PPC64
725 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
726 #else
727 domain = iommu_get_domain_for_dev(&efx->pci_dev->dev);
728 if (domain && domain->type != IOMMU_DOMAIN_IDENTITY)
729 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;
730 else
731 bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_NOIOMMU;
732 #endif /* CONFIG_PPC64 */
733
734 page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /
735 efx->rx_bufs_per_page);
736 rx_queue->page_ring = kcalloc(page_ring_size,
737 sizeof(*rx_queue->page_ring), GFP_KERNEL);
738 if (!rx_queue->page_ring)
739 rx_queue->page_ptr_mask = 0;
740 else
741 rx_queue->page_ptr_mask = page_ring_size - 1;
742 }
743
ef4_init_rx_queue(struct ef4_rx_queue * rx_queue)744 void ef4_init_rx_queue(struct ef4_rx_queue *rx_queue)
745 {
746 struct ef4_nic *efx = rx_queue->efx;
747 unsigned int max_fill, trigger, max_trigger;
748
749 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
750 "initialising RX queue %d\n", ef4_rx_queue_index(rx_queue));
751
752 /* Initialise ptr fields */
753 rx_queue->added_count = 0;
754 rx_queue->notified_count = 0;
755 rx_queue->removed_count = 0;
756 rx_queue->min_fill = -1U;
757 ef4_init_rx_recycle_ring(efx, rx_queue);
758
759 rx_queue->page_remove = 0;
760 rx_queue->page_add = rx_queue->page_ptr_mask + 1;
761 rx_queue->page_recycle_count = 0;
762 rx_queue->page_recycle_failed = 0;
763 rx_queue->page_recycle_full = 0;
764
765 /* Initialise limit fields */
766 max_fill = efx->rxq_entries - EF4_RXD_HEAD_ROOM;
767 max_trigger =
768 max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
769 if (rx_refill_threshold != 0) {
770 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
771 if (trigger > max_trigger)
772 trigger = max_trigger;
773 } else {
774 trigger = max_trigger;
775 }
776
777 rx_queue->max_fill = max_fill;
778 rx_queue->fast_fill_trigger = trigger;
779 rx_queue->refill_enabled = true;
780
781 /* Set up RX descriptor ring */
782 ef4_nic_init_rx(rx_queue);
783 }
784
ef4_fini_rx_queue(struct ef4_rx_queue * rx_queue)785 void ef4_fini_rx_queue(struct ef4_rx_queue *rx_queue)
786 {
787 int i;
788 struct ef4_nic *efx = rx_queue->efx;
789 struct ef4_rx_buffer *rx_buf;
790
791 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
792 "shutting down RX queue %d\n", ef4_rx_queue_index(rx_queue));
793
794 del_timer_sync(&rx_queue->slow_fill);
795
796 /* Release RX buffers from the current read ptr to the write ptr */
797 if (rx_queue->buffer) {
798 for (i = rx_queue->removed_count; i < rx_queue->added_count;
799 i++) {
800 unsigned index = i & rx_queue->ptr_mask;
801 rx_buf = ef4_rx_buffer(rx_queue, index);
802 ef4_fini_rx_buffer(rx_queue, rx_buf);
803 }
804 }
805
806 /* Unmap and release the pages in the recycle ring. Remove the ring. */
807 for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
808 struct page *page = rx_queue->page_ring[i];
809 struct ef4_rx_page_state *state;
810
811 if (page == NULL)
812 continue;
813
814 state = page_address(page);
815 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
816 PAGE_SIZE << efx->rx_buffer_order,
817 DMA_FROM_DEVICE);
818 put_page(page);
819 }
820 kfree(rx_queue->page_ring);
821 rx_queue->page_ring = NULL;
822 }
823
ef4_remove_rx_queue(struct ef4_rx_queue * rx_queue)824 void ef4_remove_rx_queue(struct ef4_rx_queue *rx_queue)
825 {
826 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
827 "destroying RX queue %d\n", ef4_rx_queue_index(rx_queue));
828
829 ef4_nic_remove_rx(rx_queue);
830
831 kfree(rx_queue->buffer);
832 rx_queue->buffer = NULL;
833 }
834
835
836 module_param(rx_refill_threshold, uint, 0444);
837 MODULE_PARM_DESC(rx_refill_threshold,
838 "RX descriptor ring refill threshold (%)");
839
840 #ifdef CONFIG_RFS_ACCEL
841
ef4_filter_rfs(struct net_device * net_dev,const struct sk_buff * skb,u16 rxq_index,u32 flow_id)842 int ef4_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
843 u16 rxq_index, u32 flow_id)
844 {
845 struct ef4_nic *efx = netdev_priv(net_dev);
846 struct ef4_channel *channel;
847 struct ef4_filter_spec spec;
848 struct flow_keys fk;
849 int rc;
850
851 if (flow_id == RPS_FLOW_ID_INVALID)
852 return -EINVAL;
853
854 if (!skb_flow_dissect_flow_keys(skb, &fk, 0))
855 return -EPROTONOSUPPORT;
856
857 if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6))
858 return -EPROTONOSUPPORT;
859 if (fk.control.flags & FLOW_DIS_IS_FRAGMENT)
860 return -EPROTONOSUPPORT;
861
862 ef4_filter_init_rx(&spec, EF4_FILTER_PRI_HINT,
863 efx->rx_scatter ? EF4_FILTER_FLAG_RX_SCATTER : 0,
864 rxq_index);
865 spec.match_flags =
866 EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_IP_PROTO |
867 EF4_FILTER_MATCH_LOC_HOST | EF4_FILTER_MATCH_LOC_PORT |
868 EF4_FILTER_MATCH_REM_HOST | EF4_FILTER_MATCH_REM_PORT;
869 spec.ether_type = fk.basic.n_proto;
870 spec.ip_proto = fk.basic.ip_proto;
871
872 if (fk.basic.n_proto == htons(ETH_P_IP)) {
873 spec.rem_host[0] = fk.addrs.v4addrs.src;
874 spec.loc_host[0] = fk.addrs.v4addrs.dst;
875 } else {
876 memcpy(spec.rem_host, &fk.addrs.v6addrs.src, sizeof(struct in6_addr));
877 memcpy(spec.loc_host, &fk.addrs.v6addrs.dst, sizeof(struct in6_addr));
878 }
879
880 spec.rem_port = fk.ports.src;
881 spec.loc_port = fk.ports.dst;
882
883 rc = efx->type->filter_rfs_insert(efx, &spec);
884 if (rc < 0)
885 return rc;
886
887 /* Remember this so we can check whether to expire the filter later */
888 channel = ef4_get_channel(efx, rxq_index);
889 channel->rps_flow_id[rc] = flow_id;
890 ++channel->rfs_filters_added;
891
892 if (spec.ether_type == htons(ETH_P_IP))
893 netif_info(efx, rx_status, efx->net_dev,
894 "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
895 (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
896 spec.rem_host, ntohs(spec.rem_port), spec.loc_host,
897 ntohs(spec.loc_port), rxq_index, flow_id, rc);
898 else
899 netif_info(efx, rx_status, efx->net_dev,
900 "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
901 (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
902 spec.rem_host, ntohs(spec.rem_port), spec.loc_host,
903 ntohs(spec.loc_port), rxq_index, flow_id, rc);
904
905 return rc;
906 }
907
__ef4_filter_rfs_expire(struct ef4_nic * efx,unsigned int quota)908 bool __ef4_filter_rfs_expire(struct ef4_nic *efx, unsigned int quota)
909 {
910 bool (*expire_one)(struct ef4_nic *efx, u32 flow_id, unsigned int index);
911 unsigned int channel_idx, index, size;
912 u32 flow_id;
913
914 if (!spin_trylock_bh(&efx->filter_lock))
915 return false;
916
917 expire_one = efx->type->filter_rfs_expire_one;
918 channel_idx = efx->rps_expire_channel;
919 index = efx->rps_expire_index;
920 size = efx->type->max_rx_ip_filters;
921 while (quota--) {
922 struct ef4_channel *channel = ef4_get_channel(efx, channel_idx);
923 flow_id = channel->rps_flow_id[index];
924
925 if (flow_id != RPS_FLOW_ID_INVALID &&
926 expire_one(efx, flow_id, index)) {
927 netif_info(efx, rx_status, efx->net_dev,
928 "expired filter %d [queue %u flow %u]\n",
929 index, channel_idx, flow_id);
930 channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;
931 }
932 if (++index == size) {
933 if (++channel_idx == efx->n_channels)
934 channel_idx = 0;
935 index = 0;
936 }
937 }
938 efx->rps_expire_channel = channel_idx;
939 efx->rps_expire_index = index;
940
941 spin_unlock_bh(&efx->filter_lock);
942 return true;
943 }
944
945 #endif /* CONFIG_RFS_ACCEL */
946
947 /**
948 * ef4_filter_is_mc_recipient - test whether spec is a multicast recipient
949 * @spec: Specification to test
950 *
951 * Return: %true if the specification is a non-drop RX filter that
952 * matches a local MAC address I/G bit value of 1 or matches a local
953 * IPv4 or IPv6 address value in the respective multicast address
954 * range. Otherwise %false.
955 */
ef4_filter_is_mc_recipient(const struct ef4_filter_spec * spec)956 bool ef4_filter_is_mc_recipient(const struct ef4_filter_spec *spec)
957 {
958 if (!(spec->flags & EF4_FILTER_FLAG_RX) ||
959 spec->dmaq_id == EF4_FILTER_RX_DMAQ_ID_DROP)
960 return false;
961
962 if (spec->match_flags &
963 (EF4_FILTER_MATCH_LOC_MAC | EF4_FILTER_MATCH_LOC_MAC_IG) &&
964 is_multicast_ether_addr(spec->loc_mac))
965 return true;
966
967 if ((spec->match_flags &
968 (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) ==
969 (EF4_FILTER_MATCH_ETHER_TYPE | EF4_FILTER_MATCH_LOC_HOST)) {
970 if (spec->ether_type == htons(ETH_P_IP) &&
971 ipv4_is_multicast(spec->loc_host[0]))
972 return true;
973 if (spec->ether_type == htons(ETH_P_IPV6) &&
974 ((const u8 *)spec->loc_host)[0] == 0xff)
975 return true;
976 }
977
978 return false;
979 }
980