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v6.8
  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/xdp.h>
 21#include <linux/bpf_trace.h>
 22#include "net_driver.h"
 23#include "efx.h"
 24#include "rx_common.h"
 25#include "filter.h"
 26#include "nic.h"
 27#include "selftest.h"
 28#include "workarounds.h"
 29
 30/* Preferred number of descriptors to fill at once */
 31#define EFX_RX_PREFERRED_BATCH 8U
 32
 33/* Maximum rx prefix used by any architecture. */
 34#define EFX_MAX_RX_PREFIX_SIZE 16
 
 
 
 
 35
 36/* Size of buffer allocated for skb header area. */
 37#define EFX_SKB_HEADERS  128u
 38
 
 
 
 
 
 39/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
 40#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \
 41				      EFX_RX_USR_BUF_SIZE)
 42
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 43static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
 44				     struct efx_rx_buffer *rx_buf,
 45				     int len)
 46{
 47	struct efx_nic *efx = rx_queue->efx;
 48	unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
 49
 50	if (likely(len <= max_len))
 51		return;
 52
 53	/* The packet must be discarded, but this is only a fatal error
 54	 * if the caller indicated it was
 55	 */
 56	rx_buf->flags |= EFX_RX_PKT_DISCARD;
 57
 58	if (net_ratelimit())
 59		netif_err(efx, rx_err, efx->net_dev,
 60			  "RX queue %d overlength RX event (%#x > %#x)\n",
 61			  efx_rx_queue_index(rx_queue), len, max_len);
 
 
 
 
 
 
 
 
 
 
 
 62
 63	efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
 64}
 65
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 66/* Allocate and construct an SKB around page fragments */
 67static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
 68				     struct efx_rx_buffer *rx_buf,
 69				     unsigned int n_frags,
 70				     u8 *eh, int hdr_len)
 71{
 72	struct efx_nic *efx = channel->efx;
 73	struct sk_buff *skb;
 74
 75	/* Allocate an SKB to store the headers */
 76	skb = netdev_alloc_skb(efx->net_dev,
 77			       efx->rx_ip_align + efx->rx_prefix_size +
 78			       hdr_len);
 79	if (unlikely(skb == NULL)) {
 80		atomic_inc(&efx->n_rx_noskb_drops);
 81		return NULL;
 82	}
 83
 84	EFX_WARN_ON_ONCE_PARANOID(rx_buf->len < hdr_len);
 85
 86	memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
 87	       efx->rx_prefix_size + hdr_len);
 88	skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
 89	__skb_put(skb, hdr_len);
 90
 91	/* Append the remaining page(s) onto the frag list */
 92	if (rx_buf->len > hdr_len) {
 93		rx_buf->page_offset += hdr_len;
 94		rx_buf->len -= hdr_len;
 95
 96		for (;;) {
 97			skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
 98					rx_buf->page, rx_buf->page_offset,
 99					rx_buf->len, efx->rx_buffer_truesize);
100			rx_buf->page = NULL;
101
 
102			if (skb_shinfo(skb)->nr_frags == n_frags)
103				break;
104
105			rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
106		}
107	} else {
108		__free_pages(rx_buf->page, efx->rx_buffer_order);
109		rx_buf->page = NULL;
110		n_frags = 0;
111	}
112
 
 
113	/* Move past the ethernet header */
114	skb->protocol = eth_type_trans(skb, efx->net_dev);
115
116	skb_mark_napi_id(skb, &channel->napi_str);
117
118	return skb;
119}
120
121void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
122		   unsigned int n_frags, unsigned int len, u16 flags)
123{
124	struct efx_nic *efx = rx_queue->efx;
125	struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
126	struct efx_rx_buffer *rx_buf;
127
128	rx_queue->rx_packets++;
129
130	rx_buf = efx_rx_buffer(rx_queue, index);
131	rx_buf->flags |= flags;
132
133	/* Validate the number of fragments and completed length */
134	if (n_frags == 1) {
135		if (!(flags & EFX_RX_PKT_PREFIX_LEN))
136			efx_rx_packet__check_len(rx_queue, rx_buf, len);
137	} else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) ||
138		   unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
139		   unlikely(len > n_frags * efx->rx_dma_len) ||
140		   unlikely(!efx->rx_scatter)) {
141		/* If this isn't an explicit discard request, either
142		 * the hardware or the driver is broken.
143		 */
144		WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD));
145		rx_buf->flags |= EFX_RX_PKT_DISCARD;
146	}
147
148	netif_vdbg(efx, rx_status, efx->net_dev,
149		   "RX queue %d received ids %x-%x len %d %s%s\n",
150		   efx_rx_queue_index(rx_queue), index,
151		   (index + n_frags - 1) & rx_queue->ptr_mask, len,
152		   (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
153		   (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
154
155	/* Discard packet, if instructed to do so.  Process the
156	 * previous receive first.
157	 */
158	if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
159		efx_rx_flush_packet(channel);
160		efx_discard_rx_packet(channel, rx_buf, n_frags);
161		return;
162	}
163
164	if (n_frags == 1 && !(flags & EFX_RX_PKT_PREFIX_LEN))
165		rx_buf->len = len;
166
167	/* Release and/or sync the DMA mapping - assumes all RX buffers
168	 * consumed in-order per RX queue.
169	 */
170	efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
171
172	/* Prefetch nice and early so data will (hopefully) be in cache by
173	 * the time we look at it.
174	 */
175	prefetch(efx_rx_buf_va(rx_buf));
176
177	rx_buf->page_offset += efx->rx_prefix_size;
178	rx_buf->len -= efx->rx_prefix_size;
179
180	if (n_frags > 1) {
181		/* Release/sync DMA mapping for additional fragments.
182		 * Fix length for last fragment.
183		 */
184		unsigned int tail_frags = n_frags - 1;
185
186		for (;;) {
187			rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
188			if (--tail_frags == 0)
189				break;
190			efx_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
191		}
192		rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
193		efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
194	}
195
196	/* All fragments have been DMA-synced, so recycle pages. */
197	rx_buf = efx_rx_buffer(rx_queue, index);
198	efx_recycle_rx_pages(channel, rx_buf, n_frags);
199
200	/* Pipeline receives so that we give time for packet headers to be
201	 * prefetched into cache.
202	 */
203	efx_rx_flush_packet(channel);
204	channel->rx_pkt_n_frags = n_frags;
205	channel->rx_pkt_index = index;
206}
207
208static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
209			   struct efx_rx_buffer *rx_buf,
210			   unsigned int n_frags)
211{
212	struct sk_buff *skb;
213	u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS);
214
215	skb = efx_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
216	if (unlikely(skb == NULL)) {
217		struct efx_rx_queue *rx_queue;
218
219		rx_queue = efx_channel_get_rx_queue(channel);
220		efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
221		return;
222	}
223	skb_record_rx_queue(skb, channel->rx_queue.core_index);
224
225	/* Set the SKB flags */
226	skb_checksum_none_assert(skb);
227	if (likely(rx_buf->flags & EFX_RX_PKT_CSUMMED)) {
228		skb->ip_summed = CHECKSUM_UNNECESSARY;
229		skb->csum_level = !!(rx_buf->flags & EFX_RX_PKT_CSUM_LEVEL);
230	}
231
232	efx_rx_skb_attach_timestamp(channel, skb);
233
234	if (channel->type->receive_skb)
235		if (channel->type->receive_skb(channel, skb))
236			return;
237
238	/* Pass the packet up */
239	if (channel->rx_list != NULL)
240		/* Add to list, will pass up later */
241		list_add_tail(&skb->list, channel->rx_list);
242	else
243		/* No list, so pass it up now */
244		netif_receive_skb(skb);
245}
246
247/** efx_do_xdp: perform XDP processing on a received packet
248 *
249 * Returns true if packet should still be delivered.
250 */
251static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
252		       struct efx_rx_buffer *rx_buf, u8 **ehp)
253{
254	u8 rx_prefix[EFX_MAX_RX_PREFIX_SIZE];
255	struct efx_rx_queue *rx_queue;
256	struct bpf_prog *xdp_prog;
257	struct xdp_frame *xdpf;
258	struct xdp_buff xdp;
259	u32 xdp_act;
260	s16 offset;
261	int err;
262
263	xdp_prog = rcu_dereference_bh(efx->xdp_prog);
264	if (!xdp_prog)
265		return true;
266
267	rx_queue = efx_channel_get_rx_queue(channel);
268
269	if (unlikely(channel->rx_pkt_n_frags > 1)) {
270		/* We can't do XDP on fragmented packets - drop. */
271		efx_free_rx_buffers(rx_queue, rx_buf,
272				    channel->rx_pkt_n_frags);
273		if (net_ratelimit())
274			netif_err(efx, rx_err, efx->net_dev,
275				  "XDP is not possible with multiple receive fragments (%d)\n",
276				  channel->rx_pkt_n_frags);
277		channel->n_rx_xdp_bad_drops++;
278		return false;
279	}
280
281	dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr,
282				rx_buf->len, DMA_FROM_DEVICE);
283
284	/* Save the rx prefix. */
285	EFX_WARN_ON_PARANOID(efx->rx_prefix_size > EFX_MAX_RX_PREFIX_SIZE);
286	memcpy(rx_prefix, *ehp - efx->rx_prefix_size,
287	       efx->rx_prefix_size);
288
289	xdp_init_buff(&xdp, efx->rx_page_buf_step, &rx_queue->xdp_rxq_info);
290	/* No support yet for XDP metadata */
291	xdp_prepare_buff(&xdp, *ehp - EFX_XDP_HEADROOM, EFX_XDP_HEADROOM,
292			 rx_buf->len, false);
293
294	xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp);
295
296	offset = (u8 *)xdp.data - *ehp;
297
298	switch (xdp_act) {
299	case XDP_PASS:
300		/* Fix up rx prefix. */
301		if (offset) {
302			*ehp += offset;
303			rx_buf->page_offset += offset;
304			rx_buf->len -= offset;
305			memcpy(*ehp - efx->rx_prefix_size, rx_prefix,
306			       efx->rx_prefix_size);
307		}
308		break;
309
310	case XDP_TX:
311		/* Buffer ownership passes to tx on success. */
312		xdpf = xdp_convert_buff_to_frame(&xdp);
313		err = efx_xdp_tx_buffers(efx, 1, &xdpf, true);
314		if (unlikely(err != 1)) {
315			efx_free_rx_buffers(rx_queue, rx_buf, 1);
316			if (net_ratelimit())
317				netif_err(efx, rx_err, efx->net_dev,
318					  "XDP TX failed (%d)\n", err);
319			channel->n_rx_xdp_bad_drops++;
320			trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
321		} else {
322			channel->n_rx_xdp_tx++;
323		}
324		break;
325
326	case XDP_REDIRECT:
327		err = xdp_do_redirect(efx->net_dev, &xdp, xdp_prog);
328		if (unlikely(err)) {
329			efx_free_rx_buffers(rx_queue, rx_buf, 1);
330			if (net_ratelimit())
331				netif_err(efx, rx_err, efx->net_dev,
332					  "XDP redirect failed (%d)\n", err);
333			channel->n_rx_xdp_bad_drops++;
334			trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
335		} else {
336			channel->n_rx_xdp_redirect++;
337		}
338		break;
339
340	default:
341		bpf_warn_invalid_xdp_action(efx->net_dev, xdp_prog, xdp_act);
342		efx_free_rx_buffers(rx_queue, rx_buf, 1);
343		channel->n_rx_xdp_bad_drops++;
344		trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
345		break;
346
347	case XDP_ABORTED:
348		trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
349		fallthrough;
350	case XDP_DROP:
351		efx_free_rx_buffers(rx_queue, rx_buf, 1);
352		channel->n_rx_xdp_drops++;
353		break;
354	}
355
356	return xdp_act == XDP_PASS;
357}
358
359/* Handle a received packet.  Second half: Touches packet payload. */
360void __efx_rx_packet(struct efx_channel *channel)
361{
362	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
363	struct efx_nic *efx = channel->efx;
364	struct efx_rx_buffer *rx_buf =
365		efx_rx_buffer(rx_queue, channel->rx_pkt_index);
366	u8 *eh = efx_rx_buf_va(rx_buf);
367
368	/* Read length from the prefix if necessary.  This already
369	 * excludes the length of the prefix itself.
370	 */
371	if (rx_buf->flags & EFX_RX_PKT_PREFIX_LEN) {
372		rx_buf->len = le16_to_cpup((__le16 *)
373					   (eh + efx->rx_packet_len_offset));
374		/* A known issue may prevent this being filled in;
375		 * if that happens, just drop the packet.
376		 * Must do that in the driver since passing a zero-length
377		 * packet up to the stack may cause a crash.
378		 */
379		if (unlikely(!rx_buf->len)) {
380			efx_free_rx_buffers(rx_queue, rx_buf,
381					    channel->rx_pkt_n_frags);
382			channel->n_rx_frm_trunc++;
383			goto out;
384		}
385	}
386
387	/* If we're in loopback test, then pass the packet directly to the
388	 * loopback layer, and free the rx_buf here
389	 */
390	if (unlikely(efx->loopback_selftest)) {
 
 
391		efx_loopback_rx_packet(efx, eh, rx_buf->len);
 
392		efx_free_rx_buffers(rx_queue, rx_buf,
393				    channel->rx_pkt_n_frags);
394		goto out;
395	}
396
397	if (!efx_do_xdp(efx, channel, rx_buf, &eh))
398		goto out;
399
400	if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
401		rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
402
403	if ((rx_buf->flags & EFX_RX_PKT_TCP) && !channel->type->receive_skb)
404		efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh, 0);
 
405	else
406		efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
407out:
408	channel->rx_pkt_n_frags = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
409}
v4.6
 
  1/****************************************************************************
  2 * Driver for Solarflare network controllers and boards
  3 * Copyright 2005-2006 Fen Systems Ltd.
  4 * Copyright 2005-2013 Solarflare Communications Inc.
  5 *
  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.
  9 */
 10
 11#include <linux/socket.h>
 12#include <linux/in.h>
 13#include <linux/slab.h>
 14#include <linux/ip.h>
 15#include <linux/ipv6.h>
 16#include <linux/tcp.h>
 17#include <linux/udp.h>
 18#include <linux/prefetch.h>
 19#include <linux/moduleparam.h>
 20#include <linux/iommu.h>
 21#include <net/ip.h>
 22#include <net/checksum.h>
 
 
 23#include "net_driver.h"
 24#include "efx.h"
 
 25#include "filter.h"
 26#include "nic.h"
 27#include "selftest.h"
 28#include "workarounds.h"
 29
 30/* Preferred number of descriptors to fill at once */
 31#define EFX_RX_PREFERRED_BATCH 8U
 32
 33/* Number of RX buffers to recycle pages for.  When creating the RX page recycle
 34 * ring, this number is divided by the number of buffers per page to calculate
 35 * the number of pages to store in the RX page recycle ring.
 36 */
 37#define EFX_RECYCLE_RING_SIZE_IOMMU 4096
 38#define EFX_RECYCLE_RING_SIZE_NOIOMMU (2 * EFX_RX_PREFERRED_BATCH)
 39
 40/* Size of buffer allocated for skb header area. */
 41#define EFX_SKB_HEADERS  128u
 42
 43/* This is the percentage fill level below which new RX descriptors
 44 * will be added to the RX descriptor ring.
 45 */
 46static unsigned int rx_refill_threshold;
 47
 48/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
 49#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \
 50				      EFX_RX_USR_BUF_SIZE)
 51
 52/*
 53 * RX maximum head room required.
 54 *
 55 * This must be at least 1 to prevent overflow, plus one packet-worth
 56 * to allow pipelined receives.
 57 */
 58#define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS)
 59
 60static inline u8 *efx_rx_buf_va(struct efx_rx_buffer *buf)
 61{
 62	return page_address(buf->page) + buf->page_offset;
 63}
 64
 65static inline u32 efx_rx_buf_hash(struct efx_nic *efx, const u8 *eh)
 66{
 67#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
 68	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_hash_offset));
 69#else
 70	const u8 *data = eh + efx->rx_packet_hash_offset;
 71	return (u32)data[0]	  |
 72	       (u32)data[1] << 8  |
 73	       (u32)data[2] << 16 |
 74	       (u32)data[3] << 24;
 75#endif
 76}
 77
 78static inline struct efx_rx_buffer *
 79efx_rx_buf_next(struct efx_rx_queue *rx_queue, struct efx_rx_buffer *rx_buf)
 80{
 81	if (unlikely(rx_buf == efx_rx_buffer(rx_queue, rx_queue->ptr_mask)))
 82		return efx_rx_buffer(rx_queue, 0);
 83	else
 84		return rx_buf + 1;
 85}
 86
 87static inline void efx_sync_rx_buffer(struct efx_nic *efx,
 88				      struct efx_rx_buffer *rx_buf,
 89				      unsigned int len)
 90{
 91	dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len,
 92				DMA_FROM_DEVICE);
 93}
 94
 95void efx_rx_config_page_split(struct efx_nic *efx)
 96{
 97	efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align,
 98				      EFX_RX_BUF_ALIGNMENT);
 99	efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
100		((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /
101		 efx->rx_page_buf_step);
102	efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
103		efx->rx_bufs_per_page;
104	efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH,
105					       efx->rx_bufs_per_page);
106}
107
108/* Check the RX page recycle ring for a page that can be reused. */
109static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)
110{
111	struct efx_nic *efx = rx_queue->efx;
112	struct page *page;
113	struct efx_rx_page_state *state;
114	unsigned index;
115
116	index = rx_queue->page_remove & rx_queue->page_ptr_mask;
117	page = rx_queue->page_ring[index];
118	if (page == NULL)
119		return NULL;
120
121	rx_queue->page_ring[index] = NULL;
122	/* page_remove cannot exceed page_add. */
123	if (rx_queue->page_remove != rx_queue->page_add)
124		++rx_queue->page_remove;
125
126	/* If page_count is 1 then we hold the only reference to this page. */
127	if (page_count(page) == 1) {
128		++rx_queue->page_recycle_count;
129		return page;
130	} else {
131		state = page_address(page);
132		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
133			       PAGE_SIZE << efx->rx_buffer_order,
134			       DMA_FROM_DEVICE);
135		put_page(page);
136		++rx_queue->page_recycle_failed;
137	}
138
139	return NULL;
140}
141
142/**
143 * efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers
144 *
145 * @rx_queue:		Efx RX queue
146 *
147 * This allocates a batch of pages, maps them for DMA, and populates
148 * struct efx_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 */
152static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue, bool atomic)
153{
154	struct efx_nic *efx = rx_queue->efx;
155	struct efx_rx_buffer *rx_buf;
156	struct page *page;
157	unsigned int page_offset;
158	struct efx_rx_page_state *state;
159	dma_addr_t dma_addr;
160	unsigned index, count;
161
162	count = 0;
163	do {
164		page = efx_reuse_page(rx_queue);
165		if (page == NULL) {
166			page = alloc_pages(__GFP_COLD | __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 efx_rx_page_state);
188		page_offset = sizeof(struct efx_rx_page_state);
189
190		do {
191			index = rx_queue->added_count & rx_queue->ptr_mask;
192			rx_buf = efx_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 = EFX_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 */
213static void efx_unmap_rx_buffer(struct efx_nic *efx,
214				struct efx_rx_buffer *rx_buf)
215{
216	struct page *page = rx_buf->page;
217
218	if (page) {
219		struct efx_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
227static void efx_free_rx_buffers(struct efx_rx_queue *rx_queue,
228				struct efx_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 = efx_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 */
244static void efx_recycle_rx_page(struct efx_channel *channel,
245				struct efx_rx_buffer *rx_buf)
246{
247	struct page *page = rx_buf->page;
248	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
249	struct efx_nic *efx = rx_queue->efx;
250	unsigned index;
251
252	/* Only recycle the page after processing the final buffer. */
253	if (!(rx_buf->flags & EFX_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	efx_unmap_rx_buffer(efx, rx_buf);
273	put_page(rx_buf->page);
274}
275
276static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
277			       struct efx_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 & EFX_RX_BUF_LAST_IN_PAGE) {
285		efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
286		efx_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. */
292static void efx_recycle_rx_pages(struct efx_channel *channel,
293				 struct efx_rx_buffer *rx_buf,
294				 unsigned int n_frags)
295{
296	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
297
298	do {
299		efx_recycle_rx_page(channel, rx_buf);
300		rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
301	} while (--n_frags);
302}
303
304static void efx_discard_rx_packet(struct efx_channel *channel,
305				  struct efx_rx_buffer *rx_buf,
306				  unsigned int n_frags)
307{
308	struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
309
310	efx_recycle_rx_pages(channel, rx_buf, n_frags);
311
312	efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
313}
314
315/**
316 * efx_fast_push_rx_descriptors - push new RX descriptors quickly
317 * @rx_queue:		RX descriptor queue
318 *
319 * This will aim to fill the RX descriptor queue up to
320 * @rx_queue->@max_fill. If there is insufficient atomic
321 * memory to do so, a slow fill will be scheduled.
322 *
323 * The caller must provide serialisation (none is used here). In practise,
324 * this means this function must run from the NAPI handler, or be called
325 * when NAPI is disabled.
326 */
327void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue, bool atomic)
328{
329	struct efx_nic *efx = rx_queue->efx;
330	unsigned int fill_level, batch_size;
331	int space, rc = 0;
332
333	if (!rx_queue->refill_enabled)
334		return;
335
336	/* Calculate current fill level, and exit if we don't need to fill */
337	fill_level = (rx_queue->added_count - rx_queue->removed_count);
338	EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
339	if (fill_level >= rx_queue->fast_fill_trigger)
340		goto out;
341
342	/* Record minimum fill level */
343	if (unlikely(fill_level < rx_queue->min_fill)) {
344		if (fill_level)
345			rx_queue->min_fill = fill_level;
346	}
347
348	batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
349	space = rx_queue->max_fill - fill_level;
350	EFX_BUG_ON_PARANOID(space < batch_size);
351
352	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
353		   "RX queue %d fast-filling descriptor ring from"
354		   " level %d to level %d\n",
355		   efx_rx_queue_index(rx_queue), fill_level,
356		   rx_queue->max_fill);
357
358
359	do {
360		rc = efx_init_rx_buffers(rx_queue, atomic);
361		if (unlikely(rc)) {
362			/* Ensure that we don't leave the rx queue empty */
363			if (rx_queue->added_count == rx_queue->removed_count)
364				efx_schedule_slow_fill(rx_queue);
365			goto out;
366		}
367	} while ((space -= batch_size) >= batch_size);
368
369	netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
370		   "RX queue %d fast-filled descriptor ring "
371		   "to level %d\n", efx_rx_queue_index(rx_queue),
372		   rx_queue->added_count - rx_queue->removed_count);
373
374 out:
375	if (rx_queue->notified_count != rx_queue->added_count)
376		efx_nic_notify_rx_desc(rx_queue);
377}
378
379void efx_rx_slow_fill(unsigned long context)
380{
381	struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context;
382
383	/* Post an event to cause NAPI to run and refill the queue */
384	efx_nic_generate_fill_event(rx_queue);
385	++rx_queue->slow_fill_count;
386}
387
388static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
389				     struct efx_rx_buffer *rx_buf,
390				     int len)
391{
392	struct efx_nic *efx = rx_queue->efx;
393	unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
394
395	if (likely(len <= max_len))
396		return;
397
398	/* The packet must be discarded, but this is only a fatal error
399	 * if the caller indicated it was
400	 */
401	rx_buf->flags |= EFX_RX_PKT_DISCARD;
402
403	if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) {
404		if (net_ratelimit())
405			netif_err(efx, rx_err, efx->net_dev,
406				  " RX queue %d seriously overlength "
407				  "RX event (0x%x > 0x%x+0x%x). Leaking\n",
408				  efx_rx_queue_index(rx_queue), len, max_len,
409				  efx->type->rx_buffer_padding);
410		efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
411	} else {
412		if (net_ratelimit())
413			netif_err(efx, rx_err, efx->net_dev,
414				  " RX queue %d overlength RX event "
415				  "(0x%x > 0x%x)\n",
416				  efx_rx_queue_index(rx_queue), len, max_len);
417	}
418
419	efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
420}
421
422/* Pass a received packet up through GRO.  GRO can handle pages
423 * regardless of checksum state and skbs with a good checksum.
424 */
425static void
426efx_rx_packet_gro(struct efx_channel *channel, struct efx_rx_buffer *rx_buf,
427		  unsigned int n_frags, u8 *eh)
428{
429	struct napi_struct *napi = &channel->napi_str;
430	gro_result_t gro_result;
431	struct efx_nic *efx = channel->efx;
432	struct sk_buff *skb;
433
434	skb = napi_get_frags(napi);
435	if (unlikely(!skb)) {
436		struct efx_rx_queue *rx_queue;
437
438		rx_queue = efx_channel_get_rx_queue(channel);
439		efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
440		return;
441	}
442
443	if (efx->net_dev->features & NETIF_F_RXHASH)
444		skb_set_hash(skb, efx_rx_buf_hash(efx, eh),
445			     PKT_HASH_TYPE_L3);
446	skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
447			  CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
448
449	for (;;) {
450		skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
451				   rx_buf->page, rx_buf->page_offset,
452				   rx_buf->len);
453		rx_buf->page = NULL;
454		skb->len += rx_buf->len;
455		if (skb_shinfo(skb)->nr_frags == n_frags)
456			break;
457
458		rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
459	}
460
461	skb->data_len = skb->len;
462	skb->truesize += n_frags * efx->rx_buffer_truesize;
463
464	skb_record_rx_queue(skb, channel->rx_queue.core_index);
465
466	gro_result = napi_gro_frags(napi);
467	if (gro_result != GRO_DROP)
468		channel->irq_mod_score += 2;
469}
470
471/* Allocate and construct an SKB around page fragments */
472static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
473				     struct efx_rx_buffer *rx_buf,
474				     unsigned int n_frags,
475				     u8 *eh, int hdr_len)
476{
477	struct efx_nic *efx = channel->efx;
478	struct sk_buff *skb;
479
480	/* Allocate an SKB to store the headers */
481	skb = netdev_alloc_skb(efx->net_dev,
482			       efx->rx_ip_align + efx->rx_prefix_size +
483			       hdr_len);
484	if (unlikely(skb == NULL)) {
485		atomic_inc(&efx->n_rx_noskb_drops);
486		return NULL;
487	}
488
489	EFX_BUG_ON_PARANOID(rx_buf->len < hdr_len);
490
491	memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
492	       efx->rx_prefix_size + hdr_len);
493	skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
494	__skb_put(skb, hdr_len);
495
496	/* Append the remaining page(s) onto the frag list */
497	if (rx_buf->len > hdr_len) {
498		rx_buf->page_offset += hdr_len;
499		rx_buf->len -= hdr_len;
500
501		for (;;) {
502			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
503					   rx_buf->page, rx_buf->page_offset,
504					   rx_buf->len);
505			rx_buf->page = NULL;
506			skb->len += rx_buf->len;
507			skb->data_len += rx_buf->len;
508			if (skb_shinfo(skb)->nr_frags == n_frags)
509				break;
510
511			rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
512		}
513	} else {
514		__free_pages(rx_buf->page, efx->rx_buffer_order);
515		rx_buf->page = NULL;
516		n_frags = 0;
517	}
518
519	skb->truesize += n_frags * efx->rx_buffer_truesize;
520
521	/* Move past the ethernet header */
522	skb->protocol = eth_type_trans(skb, efx->net_dev);
523
524	skb_mark_napi_id(skb, &channel->napi_str);
525
526	return skb;
527}
528
529void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
530		   unsigned int n_frags, unsigned int len, u16 flags)
531{
532	struct efx_nic *efx = rx_queue->efx;
533	struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
534	struct efx_rx_buffer *rx_buf;
535
536	rx_queue->rx_packets++;
537
538	rx_buf = efx_rx_buffer(rx_queue, index);
539	rx_buf->flags |= flags;
540
541	/* Validate the number of fragments and completed length */
542	if (n_frags == 1) {
543		if (!(flags & EFX_RX_PKT_PREFIX_LEN))
544			efx_rx_packet__check_len(rx_queue, rx_buf, len);
545	} else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) ||
546		   unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
547		   unlikely(len > n_frags * efx->rx_dma_len) ||
548		   unlikely(!efx->rx_scatter)) {
549		/* If this isn't an explicit discard request, either
550		 * the hardware or the driver is broken.
551		 */
552		WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD));
553		rx_buf->flags |= EFX_RX_PKT_DISCARD;
554	}
555
556	netif_vdbg(efx, rx_status, efx->net_dev,
557		   "RX queue %d received ids %x-%x len %d %s%s\n",
558		   efx_rx_queue_index(rx_queue), index,
559		   (index + n_frags - 1) & rx_queue->ptr_mask, len,
560		   (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
561		   (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
562
563	/* Discard packet, if instructed to do so.  Process the
564	 * previous receive first.
565	 */
566	if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
567		efx_rx_flush_packet(channel);
568		efx_discard_rx_packet(channel, rx_buf, n_frags);
569		return;
570	}
571
572	if (n_frags == 1 && !(flags & EFX_RX_PKT_PREFIX_LEN))
573		rx_buf->len = len;
574
575	/* Release and/or sync the DMA mapping - assumes all RX buffers
576	 * consumed in-order per RX queue.
577	 */
578	efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
579
580	/* Prefetch nice and early so data will (hopefully) be in cache by
581	 * the time we look at it.
582	 */
583	prefetch(efx_rx_buf_va(rx_buf));
584
585	rx_buf->page_offset += efx->rx_prefix_size;
586	rx_buf->len -= efx->rx_prefix_size;
587
588	if (n_frags > 1) {
589		/* Release/sync DMA mapping for additional fragments.
590		 * Fix length for last fragment.
591		 */
592		unsigned int tail_frags = n_frags - 1;
593
594		for (;;) {
595			rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
596			if (--tail_frags == 0)
597				break;
598			efx_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
599		}
600		rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
601		efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
602	}
603
604	/* All fragments have been DMA-synced, so recycle pages. */
605	rx_buf = efx_rx_buffer(rx_queue, index);
606	efx_recycle_rx_pages(channel, rx_buf, n_frags);
607
608	/* Pipeline receives so that we give time for packet headers to be
609	 * prefetched into cache.
610	 */
611	efx_rx_flush_packet(channel);
612	channel->rx_pkt_n_frags = n_frags;
613	channel->rx_pkt_index = index;
614}
615
616static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
617			   struct efx_rx_buffer *rx_buf,
618			   unsigned int n_frags)
619{
620	struct sk_buff *skb;
621	u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS);
622
623	skb = efx_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
624	if (unlikely(skb == NULL)) {
625		struct efx_rx_queue *rx_queue;
626
627		rx_queue = efx_channel_get_rx_queue(channel);
628		efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
629		return;
630	}
631	skb_record_rx_queue(skb, channel->rx_queue.core_index);
632
633	/* Set the SKB flags */
634	skb_checksum_none_assert(skb);
635	if (likely(rx_buf->flags & EFX_RX_PKT_CSUMMED))
636		skb->ip_summed = CHECKSUM_UNNECESSARY;
 
 
637
638	efx_rx_skb_attach_timestamp(channel, skb);
639
640	if (channel->type->receive_skb)
641		if (channel->type->receive_skb(channel, skb))
642			return;
643
644	/* Pass the packet up */
645	netif_receive_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
646}
647
648/* Handle a received packet.  Second half: Touches packet payload. */
649void __efx_rx_packet(struct efx_channel *channel)
650{
 
651	struct efx_nic *efx = channel->efx;
652	struct efx_rx_buffer *rx_buf =
653		efx_rx_buffer(&channel->rx_queue, channel->rx_pkt_index);
654	u8 *eh = efx_rx_buf_va(rx_buf);
655
656	/* Read length from the prefix if necessary.  This already
657	 * excludes the length of the prefix itself.
658	 */
659	if (rx_buf->flags & EFX_RX_PKT_PREFIX_LEN)
660		rx_buf->len = le16_to_cpup((__le16 *)
661					   (eh + efx->rx_packet_len_offset));
 
 
 
 
 
 
 
 
 
 
 
 
662
663	/* If we're in loopback test, then pass the packet directly to the
664	 * loopback layer, and free the rx_buf here
665	 */
666	if (unlikely(efx->loopback_selftest)) {
667		struct efx_rx_queue *rx_queue;
668
669		efx_loopback_rx_packet(efx, eh, rx_buf->len);
670		rx_queue = efx_channel_get_rx_queue(channel);
671		efx_free_rx_buffers(rx_queue, rx_buf,
672				    channel->rx_pkt_n_frags);
673		goto out;
674	}
675
 
 
 
676	if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
677		rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
678
679	if ((rx_buf->flags & EFX_RX_PKT_TCP) && !channel->type->receive_skb &&
680	    !efx_channel_busy_polling(channel))
681		efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh);
682	else
683		efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
684out:
685	channel->rx_pkt_n_frags = 0;
686}
687
688int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
689{
690	struct efx_nic *efx = rx_queue->efx;
691	unsigned int entries;
692	int rc;
693
694	/* Create the smallest power-of-two aligned ring */
695	entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
696	EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
697	rx_queue->ptr_mask = entries - 1;
698
699	netif_dbg(efx, probe, efx->net_dev,
700		  "creating RX queue %d size %#x mask %#x\n",
701		  efx_rx_queue_index(rx_queue), efx->rxq_entries,
702		  rx_queue->ptr_mask);
703
704	/* Allocate RX buffers */
705	rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
706				   GFP_KERNEL);
707	if (!rx_queue->buffer)
708		return -ENOMEM;
709
710	rc = efx_nic_probe_rx(rx_queue);
711	if (rc) {
712		kfree(rx_queue->buffer);
713		rx_queue->buffer = NULL;
714	}
715
716	return rc;
717}
718
719static void efx_init_rx_recycle_ring(struct efx_nic *efx,
720				     struct efx_rx_queue *rx_queue)
721{
722	unsigned int bufs_in_recycle_ring, page_ring_size;
723
724	/* Set the RX recycle ring size */
725#ifdef CONFIG_PPC64
726	bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU;
727#else
728	if (iommu_present(&pci_bus_type))
729		bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU;
730	else
731		bufs_in_recycle_ring = EFX_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	rx_queue->page_ptr_mask = page_ring_size - 1;
739}
740
741void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
742{
743	struct efx_nic *efx = rx_queue->efx;
744	unsigned int max_fill, trigger, max_trigger;
745
746	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
747		  "initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
748
749	/* Initialise ptr fields */
750	rx_queue->added_count = 0;
751	rx_queue->notified_count = 0;
752	rx_queue->removed_count = 0;
753	rx_queue->min_fill = -1U;
754	efx_init_rx_recycle_ring(efx, rx_queue);
755
756	rx_queue->page_remove = 0;
757	rx_queue->page_add = rx_queue->page_ptr_mask + 1;
758	rx_queue->page_recycle_count = 0;
759	rx_queue->page_recycle_failed = 0;
760	rx_queue->page_recycle_full = 0;
761
762	/* Initialise limit fields */
763	max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
764	max_trigger =
765		max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
766	if (rx_refill_threshold != 0) {
767		trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
768		if (trigger > max_trigger)
769			trigger = max_trigger;
770	} else {
771		trigger = max_trigger;
772	}
773
774	rx_queue->max_fill = max_fill;
775	rx_queue->fast_fill_trigger = trigger;
776	rx_queue->refill_enabled = true;
777
778	/* Set up RX descriptor ring */
779	efx_nic_init_rx(rx_queue);
780}
781
782void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
783{
784	int i;
785	struct efx_nic *efx = rx_queue->efx;
786	struct efx_rx_buffer *rx_buf;
787
788	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
789		  "shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
790
791	del_timer_sync(&rx_queue->slow_fill);
792
793	/* Release RX buffers from the current read ptr to the write ptr */
794	if (rx_queue->buffer) {
795		for (i = rx_queue->removed_count; i < rx_queue->added_count;
796		     i++) {
797			unsigned index = i & rx_queue->ptr_mask;
798			rx_buf = efx_rx_buffer(rx_queue, index);
799			efx_fini_rx_buffer(rx_queue, rx_buf);
800		}
801	}
802
803	/* Unmap and release the pages in the recycle ring. Remove the ring. */
804	for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
805		struct page *page = rx_queue->page_ring[i];
806		struct efx_rx_page_state *state;
807
808		if (page == NULL)
809			continue;
810
811		state = page_address(page);
812		dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
813			       PAGE_SIZE << efx->rx_buffer_order,
814			       DMA_FROM_DEVICE);
815		put_page(page);
816	}
817	kfree(rx_queue->page_ring);
818	rx_queue->page_ring = NULL;
819}
820
821void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
822{
823	netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
824		  "destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
825
826	efx_nic_remove_rx(rx_queue);
827
828	kfree(rx_queue->buffer);
829	rx_queue->buffer = NULL;
830}
831
832
833module_param(rx_refill_threshold, uint, 0444);
834MODULE_PARM_DESC(rx_refill_threshold,
835		 "RX descriptor ring refill threshold (%)");
836
837#ifdef CONFIG_RFS_ACCEL
838
839int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
840		   u16 rxq_index, u32 flow_id)
841{
842	struct efx_nic *efx = netdev_priv(net_dev);
843	struct efx_channel *channel;
844	struct efx_filter_spec spec;
845	const __be16 *ports;
846	__be16 ether_type;
847	int nhoff;
848	int rc;
849
850	/* The core RPS/RFS code has already parsed and validated
851	 * VLAN, IP and transport headers.  We assume they are in the
852	 * header area.
853	 */
854
855	if (skb->protocol == htons(ETH_P_8021Q)) {
856		const struct vlan_hdr *vh =
857			(const struct vlan_hdr *)skb->data;
858
859		/* We can't filter on the IP 5-tuple and the vlan
860		 * together, so just strip the vlan header and filter
861		 * on the IP part.
862		 */
863		EFX_BUG_ON_PARANOID(skb_headlen(skb) < sizeof(*vh));
864		ether_type = vh->h_vlan_encapsulated_proto;
865		nhoff = sizeof(struct vlan_hdr);
866	} else {
867		ether_type = skb->protocol;
868		nhoff = 0;
869	}
870
871	if (ether_type != htons(ETH_P_IP) && ether_type != htons(ETH_P_IPV6))
872		return -EPROTONOSUPPORT;
873
874	efx_filter_init_rx(&spec, EFX_FILTER_PRI_HINT,
875			   efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,
876			   rxq_index);
877	spec.match_flags =
878		EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO |
879		EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT |
880		EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT;
881	spec.ether_type = ether_type;
882
883	if (ether_type == htons(ETH_P_IP)) {
884		const struct iphdr *ip =
885			(const struct iphdr *)(skb->data + nhoff);
886
887		EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + sizeof(*ip));
888		if (ip_is_fragment(ip))
889			return -EPROTONOSUPPORT;
890		spec.ip_proto = ip->protocol;
891		spec.rem_host[0] = ip->saddr;
892		spec.loc_host[0] = ip->daddr;
893		EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + 4 * ip->ihl + 4);
894		ports = (const __be16 *)(skb->data + nhoff + 4 * ip->ihl);
895	} else {
896		const struct ipv6hdr *ip6 =
897			(const struct ipv6hdr *)(skb->data + nhoff);
898
899		EFX_BUG_ON_PARANOID(skb_headlen(skb) <
900				    nhoff + sizeof(*ip6) + 4);
901		spec.ip_proto = ip6->nexthdr;
902		memcpy(spec.rem_host, &ip6->saddr, sizeof(ip6->saddr));
903		memcpy(spec.loc_host, &ip6->daddr, sizeof(ip6->daddr));
904		ports = (const __be16 *)(ip6 + 1);
905	}
906
907	spec.rem_port = ports[0];
908	spec.loc_port = ports[1];
909
910	rc = efx->type->filter_rfs_insert(efx, &spec);
911	if (rc < 0)
912		return rc;
913
914	/* Remember this so we can check whether to expire the filter later */
915	efx->rps_flow_id[rc] = flow_id;
916	channel = efx_get_channel(efx, skb_get_rx_queue(skb));
917	++channel->rfs_filters_added;
918
919	if (ether_type == htons(ETH_P_IP))
920		netif_info(efx, rx_status, efx->net_dev,
921			   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
922			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
923			   spec.rem_host, ntohs(ports[0]), spec.loc_host,
924			   ntohs(ports[1]), rxq_index, flow_id, rc);
925	else
926		netif_info(efx, rx_status, efx->net_dev,
927			   "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
928			   (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
929			   spec.rem_host, ntohs(ports[0]), spec.loc_host,
930			   ntohs(ports[1]), rxq_index, flow_id, rc);
931
932	return rc;
933}
934
935bool __efx_filter_rfs_expire(struct efx_nic *efx, unsigned int quota)
936{
937	bool (*expire_one)(struct efx_nic *efx, u32 flow_id, unsigned int index);
938	unsigned int index, size;
939	u32 flow_id;
940
941	if (!spin_trylock_bh(&efx->filter_lock))
942		return false;
943
944	expire_one = efx->type->filter_rfs_expire_one;
945	index = efx->rps_expire_index;
946	size = efx->type->max_rx_ip_filters;
947	while (quota--) {
948		flow_id = efx->rps_flow_id[index];
949		if (expire_one(efx, flow_id, index))
950			netif_info(efx, rx_status, efx->net_dev,
951				   "expired filter %d [flow %u]\n",
952				   index, flow_id);
953		if (++index == size)
954			index = 0;
955	}
956	efx->rps_expire_index = index;
957
958	spin_unlock_bh(&efx->filter_lock);
959	return true;
960}
961
962#endif /* CONFIG_RFS_ACCEL */
963
964/**
965 * efx_filter_is_mc_recipient - test whether spec is a multicast recipient
966 * @spec: Specification to test
967 *
968 * Return: %true if the specification is a non-drop RX filter that
969 * matches a local MAC address I/G bit value of 1 or matches a local
970 * IPv4 or IPv6 address value in the respective multicast address
971 * range.  Otherwise %false.
972 */
973bool efx_filter_is_mc_recipient(const struct efx_filter_spec *spec)
974{
975	if (!(spec->flags & EFX_FILTER_FLAG_RX) ||
976	    spec->dmaq_id == EFX_FILTER_RX_DMAQ_ID_DROP)
977		return false;
978
979	if (spec->match_flags &
980	    (EFX_FILTER_MATCH_LOC_MAC | EFX_FILTER_MATCH_LOC_MAC_IG) &&
981	    is_multicast_ether_addr(spec->loc_mac))
982		return true;
983
984	if ((spec->match_flags &
985	     (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) ==
986	    (EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_LOC_HOST)) {
987		if (spec->ether_type == htons(ETH_P_IP) &&
988		    ipv4_is_multicast(spec->loc_host[0]))
989			return true;
990		if (spec->ether_type == htons(ETH_P_IPV6) &&
991		    ((const u8 *)spec->loc_host)[0] == 0xff)
992			return true;
993	}
994
995	return false;
996}