1 /****************************************************************************
2 * Driver for Solarflare Solarstorm network controllers and boards
3 * Copyright 2005-2006 Fen Systems Ltd.
4 * Copyright 2005-2011 Solarflare Communications Inc.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation, incorporated herein by reference.
11 #include <linux/socket.h>
13 #include <linux/slab.h>
15 #include <linux/tcp.h>
16 #include <linux/udp.h>
17 #include <linux/prefetch.h>
18 #include <linux/moduleparam.h>
19 #include <linux/iommu.h>
21 #include <net/checksum.h>
22 #include "net_driver.h"
26 #include "workarounds.h"
28 /* Preferred number of descriptors to fill at once */
29 #define EFX_RX_PREFERRED_BATCH 8U
31 /* Number of RX buffers to recycle pages for. When creating the RX page recycle
32 * ring, this number is divided by the number of buffers per page to calculate
33 * the number of pages to store in the RX page recycle ring.
35 #define EFX_RECYCLE_RING_SIZE_IOMMU 4096
36 #define EFX_RECYCLE_RING_SIZE_NOIOMMU (2 * EFX_RX_PREFERRED_BATCH)
38 /* Size of buffer allocated for skb header area. */
39 #define EFX_SKB_HEADERS 128u
41 /* This is the percentage fill level below which new RX descriptors
42 * will be added to the RX descriptor ring.
44 static unsigned int rx_refill_threshold;
46 /* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
47 #define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \
51 * RX maximum head room required.
53 * This must be at least 1 to prevent overflow, plus one packet-worth
54 * to allow pipelined receives.
56 #define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS)
58 static inline u8 *efx_rx_buf_va(struct efx_rx_buffer *buf)
60 return page_address(buf->page) + buf->page_offset;
63 static inline u32 efx_rx_buf_hash(const u8 *eh)
65 /* The ethernet header is always directly after any hash. */
66 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || NET_IP_ALIGN % 4 == 0
67 return __le32_to_cpup((const __le32 *)(eh - 4));
69 const u8 *data = eh - 4;
77 static inline struct efx_rx_buffer *
78 efx_rx_buf_next(struct efx_rx_queue *rx_queue, struct efx_rx_buffer *rx_buf)
80 if (unlikely(rx_buf == efx_rx_buffer(rx_queue, rx_queue->ptr_mask)))
81 return efx_rx_buffer(rx_queue, 0);
86 static inline void efx_sync_rx_buffer(struct efx_nic *efx,
87 struct efx_rx_buffer *rx_buf,
90 dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len,
94 void efx_rx_config_page_split(struct efx_nic *efx)
96 efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + NET_IP_ALIGN,
97 EFX_RX_BUF_ALIGNMENT);
98 efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
99 ((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /
100 efx->rx_page_buf_step);
101 efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
102 efx->rx_bufs_per_page;
103 efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH,
104 efx->rx_bufs_per_page);
107 /* Check the RX page recycle ring for a page that can be reused. */
108 static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)
110 struct efx_nic *efx = rx_queue->efx;
112 struct efx_rx_page_state *state;
115 index = rx_queue->page_remove & rx_queue->page_ptr_mask;
116 page = rx_queue->page_ring[index];
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;
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;
130 state = page_address(page);
131 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
132 PAGE_SIZE << efx->rx_buffer_order,
135 ++rx_queue->page_recycle_failed;
142 * efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers
144 * @rx_queue: Efx RX queue
146 * This allocates a batch of pages, maps them for DMA, and populates
147 * struct efx_rx_buffers for each one. Return a negative error code or
148 * 0 on success. If a single page can be used for multiple buffers,
149 * then the page will either be inserted fully, or not at all.
151 static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue)
153 struct efx_nic *efx = rx_queue->efx;
154 struct efx_rx_buffer *rx_buf;
156 unsigned int page_offset;
157 struct efx_rx_page_state *state;
159 unsigned index, count;
163 page = efx_reuse_page(rx_queue);
165 page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
166 efx->rx_buffer_order);
167 if (unlikely(page == NULL))
170 dma_map_page(&efx->pci_dev->dev, page, 0,
171 PAGE_SIZE << efx->rx_buffer_order,
173 if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
175 __free_pages(page, efx->rx_buffer_order);
178 state = page_address(page);
179 state->dma_addr = dma_addr;
181 state = page_address(page);
182 dma_addr = state->dma_addr;
185 dma_addr += sizeof(struct efx_rx_page_state);
186 page_offset = sizeof(struct efx_rx_page_state);
189 index = rx_queue->added_count & rx_queue->ptr_mask;
190 rx_buf = efx_rx_buffer(rx_queue, index);
191 rx_buf->dma_addr = dma_addr + NET_IP_ALIGN;
193 rx_buf->page_offset = page_offset + NET_IP_ALIGN;
194 rx_buf->len = efx->rx_dma_len;
196 ++rx_queue->added_count;
198 dma_addr += efx->rx_page_buf_step;
199 page_offset += efx->rx_page_buf_step;
200 } while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE);
202 rx_buf->flags = EFX_RX_BUF_LAST_IN_PAGE;
203 } while (++count < efx->rx_pages_per_batch);
208 /* Unmap a DMA-mapped page. This function is only called for the final RX
211 static void efx_unmap_rx_buffer(struct efx_nic *efx,
212 struct efx_rx_buffer *rx_buf)
214 struct page *page = rx_buf->page;
217 struct efx_rx_page_state *state = page_address(page);
218 dma_unmap_page(&efx->pci_dev->dev,
220 PAGE_SIZE << efx->rx_buffer_order,
225 static void efx_free_rx_buffer(struct efx_rx_buffer *rx_buf)
228 put_page(rx_buf->page);
233 /* Attempt to recycle the page if there is an RX recycle ring; the page can
234 * only be added if this is the final RX buffer, to prevent pages being used in
235 * the descriptor ring and appearing in the recycle ring simultaneously.
237 static void efx_recycle_rx_page(struct efx_channel *channel,
238 struct efx_rx_buffer *rx_buf)
240 struct page *page = rx_buf->page;
241 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
242 struct efx_nic *efx = rx_queue->efx;
245 /* Only recycle the page after processing the final buffer. */
246 if (!(rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE))
249 index = rx_queue->page_add & rx_queue->page_ptr_mask;
250 if (rx_queue->page_ring[index] == NULL) {
251 unsigned read_index = rx_queue->page_remove &
252 rx_queue->page_ptr_mask;
254 /* The next slot in the recycle ring is available, but
255 * increment page_remove if the read pointer currently
258 if (read_index == index)
259 ++rx_queue->page_remove;
260 rx_queue->page_ring[index] = page;
261 ++rx_queue->page_add;
264 ++rx_queue->page_recycle_full;
265 efx_unmap_rx_buffer(efx, rx_buf);
266 put_page(rx_buf->page);
269 static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
270 struct efx_rx_buffer *rx_buf)
272 /* Release the page reference we hold for the buffer. */
274 put_page(rx_buf->page);
276 /* If this is the last buffer in a page, unmap and free it. */
277 if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) {
278 efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
279 efx_free_rx_buffer(rx_buf);
284 /* Recycle the pages that are used by buffers that have just been received. */
285 static void efx_recycle_rx_pages(struct efx_channel *channel,
286 struct efx_rx_buffer *rx_buf,
287 unsigned int n_frags)
289 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
292 efx_recycle_rx_page(channel, rx_buf);
293 rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
297 static void efx_discard_rx_packet(struct efx_channel *channel,
298 struct efx_rx_buffer *rx_buf,
299 unsigned int n_frags)
301 struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
303 efx_recycle_rx_pages(channel, rx_buf, n_frags);
306 efx_free_rx_buffer(rx_buf);
307 rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
312 * efx_fast_push_rx_descriptors - push new RX descriptors quickly
313 * @rx_queue: RX descriptor queue
315 * This will aim to fill the RX descriptor queue up to
316 * @rx_queue->@max_fill. If there is insufficient atomic
317 * memory to do so, a slow fill will be scheduled.
319 * The caller must provide serialisation (none is used here). In practise,
320 * this means this function must run from the NAPI handler, or be called
321 * when NAPI is disabled.
323 void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue)
325 struct efx_nic *efx = rx_queue->efx;
326 unsigned int fill_level, batch_size;
329 /* Calculate current fill level, and exit if we don't need to fill */
330 fill_level = (rx_queue->added_count - rx_queue->removed_count);
331 EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
332 if (fill_level >= rx_queue->fast_fill_trigger)
335 /* Record minimum fill level */
336 if (unlikely(fill_level < rx_queue->min_fill)) {
338 rx_queue->min_fill = fill_level;
341 batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
342 space = rx_queue->max_fill - fill_level;
343 EFX_BUG_ON_PARANOID(space < batch_size);
345 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
346 "RX queue %d fast-filling descriptor ring from"
347 " level %d to level %d\n",
348 efx_rx_queue_index(rx_queue), fill_level,
353 rc = efx_init_rx_buffers(rx_queue);
355 /* Ensure that we don't leave the rx queue empty */
356 if (rx_queue->added_count == rx_queue->removed_count)
357 efx_schedule_slow_fill(rx_queue);
360 } while ((space -= batch_size) >= batch_size);
362 netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
363 "RX queue %d fast-filled descriptor ring "
364 "to level %d\n", efx_rx_queue_index(rx_queue),
365 rx_queue->added_count - rx_queue->removed_count);
368 if (rx_queue->notified_count != rx_queue->added_count)
369 efx_nic_notify_rx_desc(rx_queue);
372 void efx_rx_slow_fill(unsigned long context)
374 struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context;
376 /* Post an event to cause NAPI to run and refill the queue */
377 efx_nic_generate_fill_event(rx_queue);
378 ++rx_queue->slow_fill_count;
381 static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
382 struct efx_rx_buffer *rx_buf,
385 struct efx_nic *efx = rx_queue->efx;
386 unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
388 if (likely(len <= max_len))
391 /* The packet must be discarded, but this is only a fatal error
392 * if the caller indicated it was
394 rx_buf->flags |= EFX_RX_PKT_DISCARD;
396 if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) {
398 netif_err(efx, rx_err, efx->net_dev,
399 " RX queue %d seriously overlength "
400 "RX event (0x%x > 0x%x+0x%x). Leaking\n",
401 efx_rx_queue_index(rx_queue), len, max_len,
402 efx->type->rx_buffer_padding);
403 efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
406 netif_err(efx, rx_err, efx->net_dev,
407 " RX queue %d overlength RX event "
409 efx_rx_queue_index(rx_queue), len, max_len);
412 efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
415 /* Pass a received packet up through GRO. GRO can handle pages
416 * regardless of checksum state and skbs with a good checksum.
419 efx_rx_packet_gro(struct efx_channel *channel, struct efx_rx_buffer *rx_buf,
420 unsigned int n_frags, u8 *eh)
422 struct napi_struct *napi = &channel->napi_str;
423 gro_result_t gro_result;
424 struct efx_nic *efx = channel->efx;
427 skb = napi_get_frags(napi);
428 if (unlikely(!skb)) {
430 put_page(rx_buf->page);
432 rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
437 if (efx->net_dev->features & NETIF_F_RXHASH)
438 skb->rxhash = efx_rx_buf_hash(eh);
439 skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
440 CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
443 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
444 rx_buf->page, rx_buf->page_offset,
447 skb->len += rx_buf->len;
448 if (skb_shinfo(skb)->nr_frags == n_frags)
451 rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
454 skb->data_len = skb->len;
455 skb->truesize += n_frags * efx->rx_buffer_truesize;
457 skb_record_rx_queue(skb, channel->rx_queue.core_index);
459 gro_result = napi_gro_frags(napi);
460 if (gro_result != GRO_DROP)
461 channel->irq_mod_score += 2;
464 /* Allocate and construct an SKB around page fragments */
465 static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
466 struct efx_rx_buffer *rx_buf,
467 unsigned int n_frags,
470 struct efx_nic *efx = channel->efx;
473 /* Allocate an SKB to store the headers */
474 skb = netdev_alloc_skb(efx->net_dev, hdr_len + EFX_PAGE_SKB_ALIGN);
475 if (unlikely(skb == NULL))
478 EFX_BUG_ON_PARANOID(rx_buf->len < hdr_len);
480 skb_reserve(skb, EFX_PAGE_SKB_ALIGN);
481 memcpy(__skb_put(skb, hdr_len), eh, hdr_len);
483 /* Append the remaining page(s) onto the frag list */
484 if (rx_buf->len > hdr_len) {
485 rx_buf->page_offset += hdr_len;
486 rx_buf->len -= hdr_len;
489 skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
490 rx_buf->page, rx_buf->page_offset,
493 skb->len += rx_buf->len;
494 skb->data_len += rx_buf->len;
495 if (skb_shinfo(skb)->nr_frags == n_frags)
498 rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
501 __free_pages(rx_buf->page, efx->rx_buffer_order);
506 skb->truesize += n_frags * efx->rx_buffer_truesize;
508 /* Move past the ethernet header */
509 skb->protocol = eth_type_trans(skb, efx->net_dev);
514 void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
515 unsigned int n_frags, unsigned int len, u16 flags)
517 struct efx_nic *efx = rx_queue->efx;
518 struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
519 struct efx_rx_buffer *rx_buf;
521 rx_buf = efx_rx_buffer(rx_queue, index);
522 rx_buf->flags |= flags;
524 /* Validate the number of fragments and completed length */
526 efx_rx_packet__check_len(rx_queue, rx_buf, len);
527 } else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) ||
528 unlikely(len <= (n_frags - 1) * EFX_RX_USR_BUF_SIZE) ||
529 unlikely(len > n_frags * EFX_RX_USR_BUF_SIZE) ||
530 unlikely(!efx->rx_scatter)) {
531 /* If this isn't an explicit discard request, either
532 * the hardware or the driver is broken.
534 WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD));
535 rx_buf->flags |= EFX_RX_PKT_DISCARD;
538 netif_vdbg(efx, rx_status, efx->net_dev,
539 "RX queue %d received ids %x-%x len %d %s%s\n",
540 efx_rx_queue_index(rx_queue), index,
541 (index + n_frags - 1) & rx_queue->ptr_mask, len,
542 (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
543 (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
545 /* Discard packet, if instructed to do so. Process the
546 * previous receive first.
548 if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
549 efx_rx_flush_packet(channel);
550 efx_discard_rx_packet(channel, rx_buf, n_frags);
557 /* Release and/or sync the DMA mapping - assumes all RX buffers
558 * consumed in-order per RX queue.
560 efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
562 /* Prefetch nice and early so data will (hopefully) be in cache by
563 * the time we look at it.
565 prefetch(efx_rx_buf_va(rx_buf));
567 rx_buf->page_offset += efx->type->rx_buffer_hash_size;
568 rx_buf->len -= efx->type->rx_buffer_hash_size;
571 /* Release/sync DMA mapping for additional fragments.
572 * Fix length for last fragment.
574 unsigned int tail_frags = n_frags - 1;
577 rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
578 if (--tail_frags == 0)
580 efx_sync_rx_buffer(efx, rx_buf, EFX_RX_USR_BUF_SIZE);
582 rx_buf->len = len - (n_frags - 1) * EFX_RX_USR_BUF_SIZE;
583 efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
586 /* All fragments have been DMA-synced, so recycle pages. */
587 rx_buf = efx_rx_buffer(rx_queue, index);
588 efx_recycle_rx_pages(channel, rx_buf, n_frags);
590 /* Pipeline receives so that we give time for packet headers to be
591 * prefetched into cache.
593 efx_rx_flush_packet(channel);
594 channel->rx_pkt_n_frags = n_frags;
595 channel->rx_pkt_index = index;
598 static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
599 struct efx_rx_buffer *rx_buf,
600 unsigned int n_frags)
603 u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS);
605 skb = efx_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
606 if (unlikely(skb == NULL)) {
607 efx_free_rx_buffer(rx_buf);
610 skb_record_rx_queue(skb, channel->rx_queue.core_index);
612 /* Set the SKB flags */
613 skb_checksum_none_assert(skb);
614 if (likely(rx_buf->flags & EFX_RX_PKT_CSUMMED))
615 skb->ip_summed = CHECKSUM_UNNECESSARY;
617 if (channel->type->receive_skb)
618 if (channel->type->receive_skb(channel, skb))
621 /* Pass the packet up */
622 netif_receive_skb(skb);
625 /* Handle a received packet. Second half: Touches packet payload. */
626 void __efx_rx_packet(struct efx_channel *channel)
628 struct efx_nic *efx = channel->efx;
629 struct efx_rx_buffer *rx_buf =
630 efx_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
631 u8 *eh = efx_rx_buf_va(rx_buf);
633 /* If we're in loopback test, then pass the packet directly to the
634 * loopback layer, and free the rx_buf here
636 if (unlikely(efx->loopback_selftest)) {
637 efx_loopback_rx_packet(efx, eh, rx_buf->len);
638 efx_free_rx_buffer(rx_buf);
642 if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
643 rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
645 if ((rx_buf->flags & EFX_RX_PKT_TCP) && !channel->type->receive_skb)
646 efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
648 efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
650 channel->rx_pkt_n_frags = 0;
653 int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
655 struct efx_nic *efx = rx_queue->efx;
656 unsigned int entries;
659 /* Create the smallest power-of-two aligned ring */
660 entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
661 EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
662 rx_queue->ptr_mask = entries - 1;
664 netif_dbg(efx, probe, efx->net_dev,
665 "creating RX queue %d size %#x mask %#x\n",
666 efx_rx_queue_index(rx_queue), efx->rxq_entries,
669 /* Allocate RX buffers */
670 rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
672 if (!rx_queue->buffer)
675 rc = efx_nic_probe_rx(rx_queue);
677 kfree(rx_queue->buffer);
678 rx_queue->buffer = NULL;
684 static void efx_init_rx_recycle_ring(struct efx_nic *efx,
685 struct efx_rx_queue *rx_queue)
687 unsigned int bufs_in_recycle_ring, page_ring_size;
689 /* Set the RX recycle ring size */
691 bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU;
693 if (iommu_present(&pci_bus_type))
694 bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU;
696 bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_NOIOMMU;
697 #endif /* CONFIG_PPC64 */
699 page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring /
700 efx->rx_bufs_per_page);
701 rx_queue->page_ring = kcalloc(page_ring_size,
702 sizeof(*rx_queue->page_ring), GFP_KERNEL);
703 rx_queue->page_ptr_mask = page_ring_size - 1;
706 void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
708 struct efx_nic *efx = rx_queue->efx;
709 unsigned int max_fill, trigger, max_trigger;
711 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
712 "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
714 /* Initialise ptr fields */
715 rx_queue->added_count = 0;
716 rx_queue->notified_count = 0;
717 rx_queue->removed_count = 0;
718 rx_queue->min_fill = -1U;
719 efx_init_rx_recycle_ring(efx, rx_queue);
721 rx_queue->page_remove = 0;
722 rx_queue->page_add = rx_queue->page_ptr_mask + 1;
723 rx_queue->page_recycle_count = 0;
724 rx_queue->page_recycle_failed = 0;
725 rx_queue->page_recycle_full = 0;
727 /* Initialise limit fields */
728 max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
730 max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
731 if (rx_refill_threshold != 0) {
732 trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
733 if (trigger > max_trigger)
734 trigger = max_trigger;
736 trigger = max_trigger;
739 rx_queue->max_fill = max_fill;
740 rx_queue->fast_fill_trigger = trigger;
742 /* Set up RX descriptor ring */
743 rx_queue->enabled = true;
744 efx_nic_init_rx(rx_queue);
747 void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
750 struct efx_nic *efx = rx_queue->efx;
751 struct efx_rx_buffer *rx_buf;
753 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
754 "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
756 /* A flush failure might have left rx_queue->enabled */
757 rx_queue->enabled = false;
759 del_timer_sync(&rx_queue->slow_fill);
760 efx_nic_fini_rx(rx_queue);
762 /* Release RX buffers from the current read ptr to the write ptr */
763 if (rx_queue->buffer) {
764 for (i = rx_queue->removed_count; i < rx_queue->added_count;
766 unsigned index = i & rx_queue->ptr_mask;
767 rx_buf = efx_rx_buffer(rx_queue, index);
768 efx_fini_rx_buffer(rx_queue, rx_buf);
772 /* Unmap and release the pages in the recycle ring. Remove the ring. */
773 for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
774 struct page *page = rx_queue->page_ring[i];
775 struct efx_rx_page_state *state;
780 state = page_address(page);
781 dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
782 PAGE_SIZE << efx->rx_buffer_order,
786 kfree(rx_queue->page_ring);
787 rx_queue->page_ring = NULL;
790 void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
792 netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
793 "destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
795 efx_nic_remove_rx(rx_queue);
797 kfree(rx_queue->buffer);
798 rx_queue->buffer = NULL;
802 module_param(rx_refill_threshold, uint, 0444);
803 MODULE_PARM_DESC(rx_refill_threshold,
804 "RX descriptor ring refill threshold (%)");