1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2013 - 2018 Intel Corporation. */
3 
4 #include <linux/prefetch.h>
5 #include <linux/bpf_trace.h>
6 #include <net/xdp.h>
7 #include "i40e.h"
8 #include "i40e_trace.h"
9 #include "i40e_prototype.h"
10 #include "i40e_txrx_common.h"
11 #include "i40e_xsk.h"
12 
13 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
14 /**
15  * i40e_fdir - Generate a Flow Director descriptor based on fdata
16  * @tx_ring: Tx ring to send buffer on
17  * @fdata: Flow director filter data
18  * @add: Indicate if we are adding a rule or deleting one
19  *
20  **/
21 static void i40e_fdir(struct i40e_ring *tx_ring,
22 		      struct i40e_fdir_filter *fdata, bool add)
23 {
24 	struct i40e_filter_program_desc *fdir_desc;
25 	struct i40e_pf *pf = tx_ring->vsi->back;
26 	u32 flex_ptype, dtype_cmd;
27 	u16 i;
28 
29 	/* grab the next descriptor */
30 	i = tx_ring->next_to_use;
31 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
32 
33 	i++;
34 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
35 
36 	flex_ptype = I40E_TXD_FLTR_QW0_QINDEX_MASK &
37 		     (fdata->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT);
38 
39 	flex_ptype |= I40E_TXD_FLTR_QW0_FLEXOFF_MASK &
40 		      (fdata->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
41 
42 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
43 		      (fdata->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
44 
45 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
46 		      (fdata->flex_offset << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
47 
48 	/* Use LAN VSI Id if not programmed by user */
49 	flex_ptype |= I40E_TXD_FLTR_QW0_DEST_VSI_MASK &
50 		      ((u32)(fdata->dest_vsi ? : pf->vsi[pf->lan_vsi]->id) <<
51 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT);
52 
53 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
54 
55 	dtype_cmd |= add ?
56 		     I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
57 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT :
58 		     I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
59 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT;
60 
61 	dtype_cmd |= I40E_TXD_FLTR_QW1_DEST_MASK &
62 		     (fdata->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT);
63 
64 	dtype_cmd |= I40E_TXD_FLTR_QW1_FD_STATUS_MASK &
65 		     (fdata->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT);
66 
67 	if (fdata->cnt_index) {
68 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
69 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNTINDEX_MASK &
70 			     ((u32)fdata->cnt_index <<
71 			      I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT);
72 	}
73 
74 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
75 	fdir_desc->rsvd = cpu_to_le32(0);
76 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
77 	fdir_desc->fd_id = cpu_to_le32(fdata->fd_id);
78 }
79 
80 #define I40E_FD_CLEAN_DELAY 10
81 /**
82  * i40e_program_fdir_filter - Program a Flow Director filter
83  * @fdir_data: Packet data that will be filter parameters
84  * @raw_packet: the pre-allocated packet buffer for FDir
85  * @pf: The PF pointer
86  * @add: True for add/update, False for remove
87  **/
88 static int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data,
89 				    u8 *raw_packet, struct i40e_pf *pf,
90 				    bool add)
91 {
92 	struct i40e_tx_buffer *tx_buf, *first;
93 	struct i40e_tx_desc *tx_desc;
94 	struct i40e_ring *tx_ring;
95 	struct i40e_vsi *vsi;
96 	struct device *dev;
97 	dma_addr_t dma;
98 	u32 td_cmd = 0;
99 	u16 i;
100 
101 	/* find existing FDIR VSI */
102 	vsi = i40e_find_vsi_by_type(pf, I40E_VSI_FDIR);
103 	if (!vsi)
104 		return -ENOENT;
105 
106 	tx_ring = vsi->tx_rings[0];
107 	dev = tx_ring->dev;
108 
109 	/* we need two descriptors to add/del a filter and we can wait */
110 	for (i = I40E_FD_CLEAN_DELAY; I40E_DESC_UNUSED(tx_ring) < 2; i--) {
111 		if (!i)
112 			return -EAGAIN;
113 		msleep_interruptible(1);
114 	}
115 
116 	dma = dma_map_single(dev, raw_packet,
117 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
118 	if (dma_mapping_error(dev, dma))
119 		goto dma_fail;
120 
121 	/* grab the next descriptor */
122 	i = tx_ring->next_to_use;
123 	first = &tx_ring->tx_bi[i];
124 	i40e_fdir(tx_ring, fdir_data, add);
125 
126 	/* Now program a dummy descriptor */
127 	i = tx_ring->next_to_use;
128 	tx_desc = I40E_TX_DESC(tx_ring, i);
129 	tx_buf = &tx_ring->tx_bi[i];
130 
131 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
132 
133 	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
134 
135 	/* record length, and DMA address */
136 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
137 	dma_unmap_addr_set(tx_buf, dma, dma);
138 
139 	tx_desc->buffer_addr = cpu_to_le64(dma);
140 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
141 
142 	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
143 	tx_buf->raw_buf = (void *)raw_packet;
144 
145 	tx_desc->cmd_type_offset_bsz =
146 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
147 
148 	/* Force memory writes to complete before letting h/w
149 	 * know there are new descriptors to fetch.
150 	 */
151 	wmb();
152 
153 	/* Mark the data descriptor to be watched */
154 	first->next_to_watch = tx_desc;
155 
156 	writel(tx_ring->next_to_use, tx_ring->tail);
157 	return 0;
158 
159 dma_fail:
160 	return -1;
161 }
162 
163 #define IP_HEADER_OFFSET 14
164 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
165 /**
166  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
167  * @vsi: pointer to the targeted VSI
168  * @fd_data: the flow director data required for the FDir descriptor
169  * @add: true adds a filter, false removes it
170  *
171  * Returns 0 if the filters were successfully added or removed
172  **/
173 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
174 				   struct i40e_fdir_filter *fd_data,
175 				   bool add)
176 {
177 	struct i40e_pf *pf = vsi->back;
178 	struct udphdr *udp;
179 	struct iphdr *ip;
180 	u8 *raw_packet;
181 	int ret;
182 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
183 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
184 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
185 
186 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
187 	if (!raw_packet)
188 		return -ENOMEM;
189 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
190 
191 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
192 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
193 	      + sizeof(struct iphdr));
194 
195 	ip->daddr = fd_data->dst_ip;
196 	udp->dest = fd_data->dst_port;
197 	ip->saddr = fd_data->src_ip;
198 	udp->source = fd_data->src_port;
199 
200 	if (fd_data->flex_filter) {
201 		u8 *payload = raw_packet + I40E_UDPIP_DUMMY_PACKET_LEN;
202 		__be16 pattern = fd_data->flex_word;
203 		u16 off = fd_data->flex_offset;
204 
205 		*((__force __be16 *)(payload + off)) = pattern;
206 	}
207 
208 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
209 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
210 	if (ret) {
211 		dev_info(&pf->pdev->dev,
212 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
213 			 fd_data->pctype, fd_data->fd_id, ret);
214 		/* Free the packet buffer since it wasn't added to the ring */
215 		kfree(raw_packet);
216 		return -EOPNOTSUPP;
217 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
218 		if (add)
219 			dev_info(&pf->pdev->dev,
220 				 "Filter OK for PCTYPE %d loc = %d\n",
221 				 fd_data->pctype, fd_data->fd_id);
222 		else
223 			dev_info(&pf->pdev->dev,
224 				 "Filter deleted for PCTYPE %d loc = %d\n",
225 				 fd_data->pctype, fd_data->fd_id);
226 	}
227 
228 	if (add)
229 		pf->fd_udp4_filter_cnt++;
230 	else
231 		pf->fd_udp4_filter_cnt--;
232 
233 	return 0;
234 }
235 
236 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
237 /**
238  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
239  * @vsi: pointer to the targeted VSI
240  * @fd_data: the flow director data required for the FDir descriptor
241  * @add: true adds a filter, false removes it
242  *
243  * Returns 0 if the filters were successfully added or removed
244  **/
245 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
246 				   struct i40e_fdir_filter *fd_data,
247 				   bool add)
248 {
249 	struct i40e_pf *pf = vsi->back;
250 	struct tcphdr *tcp;
251 	struct iphdr *ip;
252 	u8 *raw_packet;
253 	int ret;
254 	/* Dummy packet */
255 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
256 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
257 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
258 		0x0, 0x72, 0, 0, 0, 0};
259 
260 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
261 	if (!raw_packet)
262 		return -ENOMEM;
263 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
264 
265 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
266 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
267 	      + sizeof(struct iphdr));
268 
269 	ip->daddr = fd_data->dst_ip;
270 	tcp->dest = fd_data->dst_port;
271 	ip->saddr = fd_data->src_ip;
272 	tcp->source = fd_data->src_port;
273 
274 	if (fd_data->flex_filter) {
275 		u8 *payload = raw_packet + I40E_TCPIP_DUMMY_PACKET_LEN;
276 		__be16 pattern = fd_data->flex_word;
277 		u16 off = fd_data->flex_offset;
278 
279 		*((__force __be16 *)(payload + off)) = pattern;
280 	}
281 
282 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
283 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
284 	if (ret) {
285 		dev_info(&pf->pdev->dev,
286 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
287 			 fd_data->pctype, fd_data->fd_id, ret);
288 		/* Free the packet buffer since it wasn't added to the ring */
289 		kfree(raw_packet);
290 		return -EOPNOTSUPP;
291 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
292 		if (add)
293 			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
294 				 fd_data->pctype, fd_data->fd_id);
295 		else
296 			dev_info(&pf->pdev->dev,
297 				 "Filter deleted for PCTYPE %d loc = %d\n",
298 				 fd_data->pctype, fd_data->fd_id);
299 	}
300 
301 	if (add) {
302 		pf->fd_tcp4_filter_cnt++;
303 		if ((pf->flags & I40E_FLAG_FD_ATR_ENABLED) &&
304 		    I40E_DEBUG_FD & pf->hw.debug_mask)
305 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
306 		set_bit(__I40E_FD_ATR_AUTO_DISABLED, pf->state);
307 	} else {
308 		pf->fd_tcp4_filter_cnt--;
309 	}
310 
311 	return 0;
312 }
313 
314 #define I40E_SCTPIP_DUMMY_PACKET_LEN 46
315 /**
316  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
317  * a specific flow spec
318  * @vsi: pointer to the targeted VSI
319  * @fd_data: the flow director data required for the FDir descriptor
320  * @add: true adds a filter, false removes it
321  *
322  * Returns 0 if the filters were successfully added or removed
323  **/
324 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
325 				    struct i40e_fdir_filter *fd_data,
326 				    bool add)
327 {
328 	struct i40e_pf *pf = vsi->back;
329 	struct sctphdr *sctp;
330 	struct iphdr *ip;
331 	u8 *raw_packet;
332 	int ret;
333 	/* Dummy packet */
334 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
335 		0x45, 0, 0, 0x20, 0, 0, 0x40, 0, 0x40, 0x84, 0, 0, 0, 0, 0, 0,
336 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
337 
338 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
339 	if (!raw_packet)
340 		return -ENOMEM;
341 	memcpy(raw_packet, packet, I40E_SCTPIP_DUMMY_PACKET_LEN);
342 
343 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
344 	sctp = (struct sctphdr *)(raw_packet + IP_HEADER_OFFSET
345 	      + sizeof(struct iphdr));
346 
347 	ip->daddr = fd_data->dst_ip;
348 	sctp->dest = fd_data->dst_port;
349 	ip->saddr = fd_data->src_ip;
350 	sctp->source = fd_data->src_port;
351 
352 	if (fd_data->flex_filter) {
353 		u8 *payload = raw_packet + I40E_SCTPIP_DUMMY_PACKET_LEN;
354 		__be16 pattern = fd_data->flex_word;
355 		u16 off = fd_data->flex_offset;
356 
357 		*((__force __be16 *)(payload + off)) = pattern;
358 	}
359 
360 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_SCTP;
361 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
362 	if (ret) {
363 		dev_info(&pf->pdev->dev,
364 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
365 			 fd_data->pctype, fd_data->fd_id, ret);
366 		/* Free the packet buffer since it wasn't added to the ring */
367 		kfree(raw_packet);
368 		return -EOPNOTSUPP;
369 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
370 		if (add)
371 			dev_info(&pf->pdev->dev,
372 				 "Filter OK for PCTYPE %d loc = %d\n",
373 				 fd_data->pctype, fd_data->fd_id);
374 		else
375 			dev_info(&pf->pdev->dev,
376 				 "Filter deleted for PCTYPE %d loc = %d\n",
377 				 fd_data->pctype, fd_data->fd_id);
378 	}
379 
380 	if (add)
381 		pf->fd_sctp4_filter_cnt++;
382 	else
383 		pf->fd_sctp4_filter_cnt--;
384 
385 	return 0;
386 }
387 
388 #define I40E_IP_DUMMY_PACKET_LEN 34
389 /**
390  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
391  * a specific flow spec
392  * @vsi: pointer to the targeted VSI
393  * @fd_data: the flow director data required for the FDir descriptor
394  * @add: true adds a filter, false removes it
395  *
396  * Returns 0 if the filters were successfully added or removed
397  **/
398 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
399 				  struct i40e_fdir_filter *fd_data,
400 				  bool add)
401 {
402 	struct i40e_pf *pf = vsi->back;
403 	struct iphdr *ip;
404 	u8 *raw_packet;
405 	int ret;
406 	int i;
407 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
408 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
409 		0, 0, 0, 0};
410 
411 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
412 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
413 		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
414 		if (!raw_packet)
415 			return -ENOMEM;
416 		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
417 		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
418 
419 		ip->saddr = fd_data->src_ip;
420 		ip->daddr = fd_data->dst_ip;
421 		ip->protocol = 0;
422 
423 		if (fd_data->flex_filter) {
424 			u8 *payload = raw_packet + I40E_IP_DUMMY_PACKET_LEN;
425 			__be16 pattern = fd_data->flex_word;
426 			u16 off = fd_data->flex_offset;
427 
428 			*((__force __be16 *)(payload + off)) = pattern;
429 		}
430 
431 		fd_data->pctype = i;
432 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
433 		if (ret) {
434 			dev_info(&pf->pdev->dev,
435 				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
436 				 fd_data->pctype, fd_data->fd_id, ret);
437 			/* The packet buffer wasn't added to the ring so we
438 			 * need to free it now.
439 			 */
440 			kfree(raw_packet);
441 			return -EOPNOTSUPP;
442 		} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
443 			if (add)
444 				dev_info(&pf->pdev->dev,
445 					 "Filter OK for PCTYPE %d loc = %d\n",
446 					 fd_data->pctype, fd_data->fd_id);
447 			else
448 				dev_info(&pf->pdev->dev,
449 					 "Filter deleted for PCTYPE %d loc = %d\n",
450 					 fd_data->pctype, fd_data->fd_id);
451 		}
452 	}
453 
454 	if (add)
455 		pf->fd_ip4_filter_cnt++;
456 	else
457 		pf->fd_ip4_filter_cnt--;
458 
459 	return 0;
460 }
461 
462 /**
463  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
464  * @vsi: pointer to the targeted VSI
465  * @input: filter to add or delete
466  * @add: true adds a filter, false removes it
467  *
468  **/
469 int i40e_add_del_fdir(struct i40e_vsi *vsi,
470 		      struct i40e_fdir_filter *input, bool add)
471 {
472 	struct i40e_pf *pf = vsi->back;
473 	int ret;
474 
475 	switch (input->flow_type & ~FLOW_EXT) {
476 	case TCP_V4_FLOW:
477 		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
478 		break;
479 	case UDP_V4_FLOW:
480 		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
481 		break;
482 	case SCTP_V4_FLOW:
483 		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
484 		break;
485 	case IP_USER_FLOW:
486 		switch (input->ip4_proto) {
487 		case IPPROTO_TCP:
488 			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
489 			break;
490 		case IPPROTO_UDP:
491 			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
492 			break;
493 		case IPPROTO_SCTP:
494 			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
495 			break;
496 		case IPPROTO_IP:
497 			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
498 			break;
499 		default:
500 			/* We cannot support masking based on protocol */
501 			dev_info(&pf->pdev->dev, "Unsupported IPv4 protocol 0x%02x\n",
502 				 input->ip4_proto);
503 			return -EINVAL;
504 		}
505 		break;
506 	default:
507 		dev_info(&pf->pdev->dev, "Unsupported flow type 0x%02x\n",
508 			 input->flow_type);
509 		return -EINVAL;
510 	}
511 
512 	/* The buffer allocated here will be normally be freed by
513 	 * i40e_clean_fdir_tx_irq() as it reclaims resources after transmit
514 	 * completion. In the event of an error adding the buffer to the FDIR
515 	 * ring, it will immediately be freed. It may also be freed by
516 	 * i40e_clean_tx_ring() when closing the VSI.
517 	 */
518 	return ret;
519 }
520 
521 /**
522  * i40e_fd_handle_status - check the Programming Status for FD
523  * @rx_ring: the Rx ring for this descriptor
524  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
525  * @prog_id: the id originally used for programming
526  *
527  * This is used to verify if the FD programming or invalidation
528  * requested by SW to the HW is successful or not and take actions accordingly.
529  **/
530 void i40e_fd_handle_status(struct i40e_ring *rx_ring,
531 			   union i40e_rx_desc *rx_desc, u8 prog_id)
532 {
533 	struct i40e_pf *pf = rx_ring->vsi->back;
534 	struct pci_dev *pdev = pf->pdev;
535 	u32 fcnt_prog, fcnt_avail;
536 	u32 error;
537 	u64 qw;
538 
539 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
540 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
541 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
542 
543 	if (error == BIT(I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
544 		pf->fd_inv = le32_to_cpu(rx_desc->wb.qword0.hi_dword.fd_id);
545 		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
546 		    (I40E_DEBUG_FD & pf->hw.debug_mask))
547 			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
548 				 pf->fd_inv);
549 
550 		/* Check if the programming error is for ATR.
551 		 * If so, auto disable ATR and set a state for
552 		 * flush in progress. Next time we come here if flush is in
553 		 * progress do nothing, once flush is complete the state will
554 		 * be cleared.
555 		 */
556 		if (test_bit(__I40E_FD_FLUSH_REQUESTED, pf->state))
557 			return;
558 
559 		pf->fd_add_err++;
560 		/* store the current atr filter count */
561 		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
562 
563 		if ((rx_desc->wb.qword0.hi_dword.fd_id == 0) &&
564 		    test_bit(__I40E_FD_SB_AUTO_DISABLED, pf->state)) {
565 			/* These set_bit() calls aren't atomic with the
566 			 * test_bit() here, but worse case we potentially
567 			 * disable ATR and queue a flush right after SB
568 			 * support is re-enabled. That shouldn't cause an
569 			 * issue in practice
570 			 */
571 			set_bit(__I40E_FD_ATR_AUTO_DISABLED, pf->state);
572 			set_bit(__I40E_FD_FLUSH_REQUESTED, pf->state);
573 		}
574 
575 		/* filter programming failed most likely due to table full */
576 		fcnt_prog = i40e_get_global_fd_count(pf);
577 		fcnt_avail = pf->fdir_pf_filter_count;
578 		/* If ATR is running fcnt_prog can quickly change,
579 		 * if we are very close to full, it makes sense to disable
580 		 * FD ATR/SB and then re-enable it when there is room.
581 		 */
582 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
583 			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
584 			    !test_and_set_bit(__I40E_FD_SB_AUTO_DISABLED,
585 					      pf->state))
586 				if (I40E_DEBUG_FD & pf->hw.debug_mask)
587 					dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
588 		}
589 	} else if (error == BIT(I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
590 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
591 			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
592 				 rx_desc->wb.qword0.hi_dword.fd_id);
593 	}
594 }
595 
596 /**
597  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
598  * @ring:      the ring that owns the buffer
599  * @tx_buffer: the buffer to free
600  **/
601 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
602 					    struct i40e_tx_buffer *tx_buffer)
603 {
604 	if (tx_buffer->skb) {
605 		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
606 			kfree(tx_buffer->raw_buf);
607 		else if (ring_is_xdp(ring))
608 			xdp_return_frame(tx_buffer->xdpf);
609 		else
610 			dev_kfree_skb_any(tx_buffer->skb);
611 		if (dma_unmap_len(tx_buffer, len))
612 			dma_unmap_single(ring->dev,
613 					 dma_unmap_addr(tx_buffer, dma),
614 					 dma_unmap_len(tx_buffer, len),
615 					 DMA_TO_DEVICE);
616 	} else if (dma_unmap_len(tx_buffer, len)) {
617 		dma_unmap_page(ring->dev,
618 			       dma_unmap_addr(tx_buffer, dma),
619 			       dma_unmap_len(tx_buffer, len),
620 			       DMA_TO_DEVICE);
621 	}
622 
623 	tx_buffer->next_to_watch = NULL;
624 	tx_buffer->skb = NULL;
625 	dma_unmap_len_set(tx_buffer, len, 0);
626 	/* tx_buffer must be completely set up in the transmit path */
627 }
628 
629 /**
630  * i40e_clean_tx_ring - Free any empty Tx buffers
631  * @tx_ring: ring to be cleaned
632  **/
633 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
634 {
635 	unsigned long bi_size;
636 	u16 i;
637 
638 	if (ring_is_xdp(tx_ring) && tx_ring->xsk_umem) {
639 		i40e_xsk_clean_tx_ring(tx_ring);
640 	} else {
641 		/* ring already cleared, nothing to do */
642 		if (!tx_ring->tx_bi)
643 			return;
644 
645 		/* Free all the Tx ring sk_buffs */
646 		for (i = 0; i < tx_ring->count; i++)
647 			i40e_unmap_and_free_tx_resource(tx_ring,
648 							&tx_ring->tx_bi[i]);
649 	}
650 
651 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
652 	memset(tx_ring->tx_bi, 0, bi_size);
653 
654 	/* Zero out the descriptor ring */
655 	memset(tx_ring->desc, 0, tx_ring->size);
656 
657 	tx_ring->next_to_use = 0;
658 	tx_ring->next_to_clean = 0;
659 
660 	if (!tx_ring->netdev)
661 		return;
662 
663 	/* cleanup Tx queue statistics */
664 	netdev_tx_reset_queue(txring_txq(tx_ring));
665 }
666 
667 /**
668  * i40e_free_tx_resources - Free Tx resources per queue
669  * @tx_ring: Tx descriptor ring for a specific queue
670  *
671  * Free all transmit software resources
672  **/
673 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
674 {
675 	i40e_clean_tx_ring(tx_ring);
676 	kfree(tx_ring->tx_bi);
677 	tx_ring->tx_bi = NULL;
678 
679 	if (tx_ring->desc) {
680 		dma_free_coherent(tx_ring->dev, tx_ring->size,
681 				  tx_ring->desc, tx_ring->dma);
682 		tx_ring->desc = NULL;
683 	}
684 }
685 
686 /**
687  * i40e_get_tx_pending - how many tx descriptors not processed
688  * @ring: the ring of descriptors
689  * @in_sw: use SW variables
690  *
691  * Since there is no access to the ring head register
692  * in XL710, we need to use our local copies
693  **/
694 u32 i40e_get_tx_pending(struct i40e_ring *ring, bool in_sw)
695 {
696 	u32 head, tail;
697 
698 	if (!in_sw) {
699 		head = i40e_get_head(ring);
700 		tail = readl(ring->tail);
701 	} else {
702 		head = ring->next_to_clean;
703 		tail = ring->next_to_use;
704 	}
705 
706 	if (head != tail)
707 		return (head < tail) ?
708 			tail - head : (tail + ring->count - head);
709 
710 	return 0;
711 }
712 
713 /**
714  * i40e_detect_recover_hung - Function to detect and recover hung_queues
715  * @vsi:  pointer to vsi struct with tx queues
716  *
717  * VSI has netdev and netdev has TX queues. This function is to check each of
718  * those TX queues if they are hung, trigger recovery by issuing SW interrupt.
719  **/
720 void i40e_detect_recover_hung(struct i40e_vsi *vsi)
721 {
722 	struct i40e_ring *tx_ring = NULL;
723 	struct net_device *netdev;
724 	unsigned int i;
725 	int packets;
726 
727 	if (!vsi)
728 		return;
729 
730 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
731 		return;
732 
733 	netdev = vsi->netdev;
734 	if (!netdev)
735 		return;
736 
737 	if (!netif_carrier_ok(netdev))
738 		return;
739 
740 	for (i = 0; i < vsi->num_queue_pairs; i++) {
741 		tx_ring = vsi->tx_rings[i];
742 		if (tx_ring && tx_ring->desc) {
743 			/* If packet counter has not changed the queue is
744 			 * likely stalled, so force an interrupt for this
745 			 * queue.
746 			 *
747 			 * prev_pkt_ctr would be negative if there was no
748 			 * pending work.
749 			 */
750 			packets = tx_ring->stats.packets & INT_MAX;
751 			if (tx_ring->tx_stats.prev_pkt_ctr == packets) {
752 				i40e_force_wb(vsi, tx_ring->q_vector);
753 				continue;
754 			}
755 
756 			/* Memory barrier between read of packet count and call
757 			 * to i40e_get_tx_pending()
758 			 */
759 			smp_rmb();
760 			tx_ring->tx_stats.prev_pkt_ctr =
761 			    i40e_get_tx_pending(tx_ring, true) ? packets : -1;
762 		}
763 	}
764 }
765 
766 /**
767  * i40e_clean_tx_irq - Reclaim resources after transmit completes
768  * @vsi: the VSI we care about
769  * @tx_ring: Tx ring to clean
770  * @napi_budget: Used to determine if we are in netpoll
771  *
772  * Returns true if there's any budget left (e.g. the clean is finished)
773  **/
774 static bool i40e_clean_tx_irq(struct i40e_vsi *vsi,
775 			      struct i40e_ring *tx_ring, int napi_budget)
776 {
777 	u16 i = tx_ring->next_to_clean;
778 	struct i40e_tx_buffer *tx_buf;
779 	struct i40e_tx_desc *tx_head;
780 	struct i40e_tx_desc *tx_desc;
781 	unsigned int total_bytes = 0, total_packets = 0;
782 	unsigned int budget = vsi->work_limit;
783 
784 	tx_buf = &tx_ring->tx_bi[i];
785 	tx_desc = I40E_TX_DESC(tx_ring, i);
786 	i -= tx_ring->count;
787 
788 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
789 
790 	do {
791 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
792 
793 		/* if next_to_watch is not set then there is no work pending */
794 		if (!eop_desc)
795 			break;
796 
797 		/* prevent any other reads prior to eop_desc */
798 		smp_rmb();
799 
800 		i40e_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
801 		/* we have caught up to head, no work left to do */
802 		if (tx_head == tx_desc)
803 			break;
804 
805 		/* clear next_to_watch to prevent false hangs */
806 		tx_buf->next_to_watch = NULL;
807 
808 		/* update the statistics for this packet */
809 		total_bytes += tx_buf->bytecount;
810 		total_packets += tx_buf->gso_segs;
811 
812 		/* free the skb/XDP data */
813 		if (ring_is_xdp(tx_ring))
814 			xdp_return_frame(tx_buf->xdpf);
815 		else
816 			napi_consume_skb(tx_buf->skb, napi_budget);
817 
818 		/* unmap skb header data */
819 		dma_unmap_single(tx_ring->dev,
820 				 dma_unmap_addr(tx_buf, dma),
821 				 dma_unmap_len(tx_buf, len),
822 				 DMA_TO_DEVICE);
823 
824 		/* clear tx_buffer data */
825 		tx_buf->skb = NULL;
826 		dma_unmap_len_set(tx_buf, len, 0);
827 
828 		/* unmap remaining buffers */
829 		while (tx_desc != eop_desc) {
830 			i40e_trace(clean_tx_irq_unmap,
831 				   tx_ring, tx_desc, tx_buf);
832 
833 			tx_buf++;
834 			tx_desc++;
835 			i++;
836 			if (unlikely(!i)) {
837 				i -= tx_ring->count;
838 				tx_buf = tx_ring->tx_bi;
839 				tx_desc = I40E_TX_DESC(tx_ring, 0);
840 			}
841 
842 			/* unmap any remaining paged data */
843 			if (dma_unmap_len(tx_buf, len)) {
844 				dma_unmap_page(tx_ring->dev,
845 					       dma_unmap_addr(tx_buf, dma),
846 					       dma_unmap_len(tx_buf, len),
847 					       DMA_TO_DEVICE);
848 				dma_unmap_len_set(tx_buf, len, 0);
849 			}
850 		}
851 
852 		/* move us one more past the eop_desc for start of next pkt */
853 		tx_buf++;
854 		tx_desc++;
855 		i++;
856 		if (unlikely(!i)) {
857 			i -= tx_ring->count;
858 			tx_buf = tx_ring->tx_bi;
859 			tx_desc = I40E_TX_DESC(tx_ring, 0);
860 		}
861 
862 		prefetch(tx_desc);
863 
864 		/* update budget accounting */
865 		budget--;
866 	} while (likely(budget));
867 
868 	i += tx_ring->count;
869 	tx_ring->next_to_clean = i;
870 	i40e_update_tx_stats(tx_ring, total_packets, total_bytes);
871 	i40e_arm_wb(tx_ring, vsi, budget);
872 
873 	if (ring_is_xdp(tx_ring))
874 		return !!budget;
875 
876 	/* notify netdev of completed buffers */
877 	netdev_tx_completed_queue(txring_txq(tx_ring),
878 				  total_packets, total_bytes);
879 
880 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
881 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
882 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
883 		/* Make sure that anybody stopping the queue after this
884 		 * sees the new next_to_clean.
885 		 */
886 		smp_mb();
887 		if (__netif_subqueue_stopped(tx_ring->netdev,
888 					     tx_ring->queue_index) &&
889 		   !test_bit(__I40E_VSI_DOWN, vsi->state)) {
890 			netif_wake_subqueue(tx_ring->netdev,
891 					    tx_ring->queue_index);
892 			++tx_ring->tx_stats.restart_queue;
893 		}
894 	}
895 
896 	return !!budget;
897 }
898 
899 /**
900  * i40e_enable_wb_on_itr - Arm hardware to do a wb, interrupts are not enabled
901  * @vsi: the VSI we care about
902  * @q_vector: the vector on which to enable writeback
903  *
904  **/
905 static void i40e_enable_wb_on_itr(struct i40e_vsi *vsi,
906 				  struct i40e_q_vector *q_vector)
907 {
908 	u16 flags = q_vector->tx.ring[0].flags;
909 	u32 val;
910 
911 	if (!(flags & I40E_TXR_FLAGS_WB_ON_ITR))
912 		return;
913 
914 	if (q_vector->arm_wb_state)
915 		return;
916 
917 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
918 		val = I40E_PFINT_DYN_CTLN_WB_ON_ITR_MASK |
919 		      I40E_PFINT_DYN_CTLN_ITR_INDX_MASK; /* set noitr */
920 
921 		wr32(&vsi->back->hw,
922 		     I40E_PFINT_DYN_CTLN(q_vector->reg_idx),
923 		     val);
924 	} else {
925 		val = I40E_PFINT_DYN_CTL0_WB_ON_ITR_MASK |
926 		      I40E_PFINT_DYN_CTL0_ITR_INDX_MASK; /* set noitr */
927 
928 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
929 	}
930 	q_vector->arm_wb_state = true;
931 }
932 
933 /**
934  * i40e_force_wb - Issue SW Interrupt so HW does a wb
935  * @vsi: the VSI we care about
936  * @q_vector: the vector  on which to force writeback
937  *
938  **/
939 void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
940 {
941 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
942 		u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
943 			  I40E_PFINT_DYN_CTLN_ITR_INDX_MASK | /* set noitr */
944 			  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
945 			  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
946 			  /* allow 00 to be written to the index */
947 
948 		wr32(&vsi->back->hw,
949 		     I40E_PFINT_DYN_CTLN(q_vector->reg_idx), val);
950 	} else {
951 		u32 val = I40E_PFINT_DYN_CTL0_INTENA_MASK |
952 			  I40E_PFINT_DYN_CTL0_ITR_INDX_MASK | /* set noitr */
953 			  I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK |
954 			  I40E_PFINT_DYN_CTL0_SW_ITR_INDX_ENA_MASK;
955 			/* allow 00 to be written to the index */
956 
957 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
958 	}
959 }
960 
961 static inline bool i40e_container_is_rx(struct i40e_q_vector *q_vector,
962 					struct i40e_ring_container *rc)
963 {
964 	return &q_vector->rx == rc;
965 }
966 
967 static inline unsigned int i40e_itr_divisor(struct i40e_q_vector *q_vector)
968 {
969 	unsigned int divisor;
970 
971 	switch (q_vector->vsi->back->hw.phy.link_info.link_speed) {
972 	case I40E_LINK_SPEED_40GB:
973 		divisor = I40E_ITR_ADAPTIVE_MIN_INC * 1024;
974 		break;
975 	case I40E_LINK_SPEED_25GB:
976 	case I40E_LINK_SPEED_20GB:
977 		divisor = I40E_ITR_ADAPTIVE_MIN_INC * 512;
978 		break;
979 	default:
980 	case I40E_LINK_SPEED_10GB:
981 		divisor = I40E_ITR_ADAPTIVE_MIN_INC * 256;
982 		break;
983 	case I40E_LINK_SPEED_1GB:
984 	case I40E_LINK_SPEED_100MB:
985 		divisor = I40E_ITR_ADAPTIVE_MIN_INC * 32;
986 		break;
987 	}
988 
989 	return divisor;
990 }
991 
992 /**
993  * i40e_update_itr - update the dynamic ITR value based on statistics
994  * @q_vector: structure containing interrupt and ring information
995  * @rc: structure containing ring performance data
996  *
997  * Stores a new ITR value based on packets and byte
998  * counts during the last interrupt.  The advantage of per interrupt
999  * computation is faster updates and more accurate ITR for the current
1000  * traffic pattern.  Constants in this function were computed
1001  * based on theoretical maximum wire speed and thresholds were set based
1002  * on testing data as well as attempting to minimize response time
1003  * while increasing bulk throughput.
1004  **/
1005 static void i40e_update_itr(struct i40e_q_vector *q_vector,
1006 			    struct i40e_ring_container *rc)
1007 {
1008 	unsigned int avg_wire_size, packets, bytes, itr;
1009 	unsigned long next_update = jiffies;
1010 
1011 	/* If we don't have any rings just leave ourselves set for maximum
1012 	 * possible latency so we take ourselves out of the equation.
1013 	 */
1014 	if (!rc->ring || !ITR_IS_DYNAMIC(rc->ring->itr_setting))
1015 		return;
1016 
1017 	/* For Rx we want to push the delay up and default to low latency.
1018 	 * for Tx we want to pull the delay down and default to high latency.
1019 	 */
1020 	itr = i40e_container_is_rx(q_vector, rc) ?
1021 	      I40E_ITR_ADAPTIVE_MIN_USECS | I40E_ITR_ADAPTIVE_LATENCY :
1022 	      I40E_ITR_ADAPTIVE_MAX_USECS | I40E_ITR_ADAPTIVE_LATENCY;
1023 
1024 	/* If we didn't update within up to 1 - 2 jiffies we can assume
1025 	 * that either packets are coming in so slow there hasn't been
1026 	 * any work, or that there is so much work that NAPI is dealing
1027 	 * with interrupt moderation and we don't need to do anything.
1028 	 */
1029 	if (time_after(next_update, rc->next_update))
1030 		goto clear_counts;
1031 
1032 	/* If itr_countdown is set it means we programmed an ITR within
1033 	 * the last 4 interrupt cycles. This has a side effect of us
1034 	 * potentially firing an early interrupt. In order to work around
1035 	 * this we need to throw out any data received for a few
1036 	 * interrupts following the update.
1037 	 */
1038 	if (q_vector->itr_countdown) {
1039 		itr = rc->target_itr;
1040 		goto clear_counts;
1041 	}
1042 
1043 	packets = rc->total_packets;
1044 	bytes = rc->total_bytes;
1045 
1046 	if (i40e_container_is_rx(q_vector, rc)) {
1047 		/* If Rx there are 1 to 4 packets and bytes are less than
1048 		 * 9000 assume insufficient data to use bulk rate limiting
1049 		 * approach unless Tx is already in bulk rate limiting. We
1050 		 * are likely latency driven.
1051 		 */
1052 		if (packets && packets < 4 && bytes < 9000 &&
1053 		    (q_vector->tx.target_itr & I40E_ITR_ADAPTIVE_LATENCY)) {
1054 			itr = I40E_ITR_ADAPTIVE_LATENCY;
1055 			goto adjust_by_size;
1056 		}
1057 	} else if (packets < 4) {
1058 		/* If we have Tx and Rx ITR maxed and Tx ITR is running in
1059 		 * bulk mode and we are receiving 4 or fewer packets just
1060 		 * reset the ITR_ADAPTIVE_LATENCY bit for latency mode so
1061 		 * that the Rx can relax.
1062 		 */
1063 		if (rc->target_itr == I40E_ITR_ADAPTIVE_MAX_USECS &&
1064 		    (q_vector->rx.target_itr & I40E_ITR_MASK) ==
1065 		     I40E_ITR_ADAPTIVE_MAX_USECS)
1066 			goto clear_counts;
1067 	} else if (packets > 32) {
1068 		/* If we have processed over 32 packets in a single interrupt
1069 		 * for Tx assume we need to switch over to "bulk" mode.
1070 		 */
1071 		rc->target_itr &= ~I40E_ITR_ADAPTIVE_LATENCY;
1072 	}
1073 
1074 	/* We have no packets to actually measure against. This means
1075 	 * either one of the other queues on this vector is active or
1076 	 * we are a Tx queue doing TSO with too high of an interrupt rate.
1077 	 *
1078 	 * Between 4 and 56 we can assume that our current interrupt delay
1079 	 * is only slightly too low. As such we should increase it by a small
1080 	 * fixed amount.
1081 	 */
1082 	if (packets < 56) {
1083 		itr = rc->target_itr + I40E_ITR_ADAPTIVE_MIN_INC;
1084 		if ((itr & I40E_ITR_MASK) > I40E_ITR_ADAPTIVE_MAX_USECS) {
1085 			itr &= I40E_ITR_ADAPTIVE_LATENCY;
1086 			itr += I40E_ITR_ADAPTIVE_MAX_USECS;
1087 		}
1088 		goto clear_counts;
1089 	}
1090 
1091 	if (packets <= 256) {
1092 		itr = min(q_vector->tx.current_itr, q_vector->rx.current_itr);
1093 		itr &= I40E_ITR_MASK;
1094 
1095 		/* Between 56 and 112 is our "goldilocks" zone where we are
1096 		 * working out "just right". Just report that our current
1097 		 * ITR is good for us.
1098 		 */
1099 		if (packets <= 112)
1100 			goto clear_counts;
1101 
1102 		/* If packet count is 128 or greater we are likely looking
1103 		 * at a slight overrun of the delay we want. Try halving
1104 		 * our delay to see if that will cut the number of packets
1105 		 * in half per interrupt.
1106 		 */
1107 		itr /= 2;
1108 		itr &= I40E_ITR_MASK;
1109 		if (itr < I40E_ITR_ADAPTIVE_MIN_USECS)
1110 			itr = I40E_ITR_ADAPTIVE_MIN_USECS;
1111 
1112 		goto clear_counts;
1113 	}
1114 
1115 	/* The paths below assume we are dealing with a bulk ITR since
1116 	 * number of packets is greater than 256. We are just going to have
1117 	 * to compute a value and try to bring the count under control,
1118 	 * though for smaller packet sizes there isn't much we can do as
1119 	 * NAPI polling will likely be kicking in sooner rather than later.
1120 	 */
1121 	itr = I40E_ITR_ADAPTIVE_BULK;
1122 
1123 adjust_by_size:
1124 	/* If packet counts are 256 or greater we can assume we have a gross
1125 	 * overestimation of what the rate should be. Instead of trying to fine
1126 	 * tune it just use the formula below to try and dial in an exact value
1127 	 * give the current packet size of the frame.
1128 	 */
1129 	avg_wire_size = bytes / packets;
1130 
1131 	/* The following is a crude approximation of:
1132 	 *  wmem_default / (size + overhead) = desired_pkts_per_int
1133 	 *  rate / bits_per_byte / (size + ethernet overhead) = pkt_rate
1134 	 *  (desired_pkt_rate / pkt_rate) * usecs_per_sec = ITR value
1135 	 *
1136 	 * Assuming wmem_default is 212992 and overhead is 640 bytes per
1137 	 * packet, (256 skb, 64 headroom, 320 shared info), we can reduce the
1138 	 * formula down to
1139 	 *
1140 	 *  (170 * (size + 24)) / (size + 640) = ITR
1141 	 *
1142 	 * We first do some math on the packet size and then finally bitshift
1143 	 * by 8 after rounding up. We also have to account for PCIe link speed
1144 	 * difference as ITR scales based on this.
1145 	 */
1146 	if (avg_wire_size <= 60) {
1147 		/* Start at 250k ints/sec */
1148 		avg_wire_size = 4096;
1149 	} else if (avg_wire_size <= 380) {
1150 		/* 250K ints/sec to 60K ints/sec */
1151 		avg_wire_size *= 40;
1152 		avg_wire_size += 1696;
1153 	} else if (avg_wire_size <= 1084) {
1154 		/* 60K ints/sec to 36K ints/sec */
1155 		avg_wire_size *= 15;
1156 		avg_wire_size += 11452;
1157 	} else if (avg_wire_size <= 1980) {
1158 		/* 36K ints/sec to 30K ints/sec */
1159 		avg_wire_size *= 5;
1160 		avg_wire_size += 22420;
1161 	} else {
1162 		/* plateau at a limit of 30K ints/sec */
1163 		avg_wire_size = 32256;
1164 	}
1165 
1166 	/* If we are in low latency mode halve our delay which doubles the
1167 	 * rate to somewhere between 100K to 16K ints/sec
1168 	 */
1169 	if (itr & I40E_ITR_ADAPTIVE_LATENCY)
1170 		avg_wire_size /= 2;
1171 
1172 	/* Resultant value is 256 times larger than it needs to be. This
1173 	 * gives us room to adjust the value as needed to either increase
1174 	 * or decrease the value based on link speeds of 10G, 2.5G, 1G, etc.
1175 	 *
1176 	 * Use addition as we have already recorded the new latency flag
1177 	 * for the ITR value.
1178 	 */
1179 	itr += DIV_ROUND_UP(avg_wire_size, i40e_itr_divisor(q_vector)) *
1180 	       I40E_ITR_ADAPTIVE_MIN_INC;
1181 
1182 	if ((itr & I40E_ITR_MASK) > I40E_ITR_ADAPTIVE_MAX_USECS) {
1183 		itr &= I40E_ITR_ADAPTIVE_LATENCY;
1184 		itr += I40E_ITR_ADAPTIVE_MAX_USECS;
1185 	}
1186 
1187 clear_counts:
1188 	/* write back value */
1189 	rc->target_itr = itr;
1190 
1191 	/* next update should occur within next jiffy */
1192 	rc->next_update = next_update + 1;
1193 
1194 	rc->total_bytes = 0;
1195 	rc->total_packets = 0;
1196 }
1197 
1198 /**
1199  * i40e_reuse_rx_page - page flip buffer and store it back on the ring
1200  * @rx_ring: rx descriptor ring to store buffers on
1201  * @old_buff: donor buffer to have page reused
1202  *
1203  * Synchronizes page for reuse by the adapter
1204  **/
1205 static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
1206 			       struct i40e_rx_buffer *old_buff)
1207 {
1208 	struct i40e_rx_buffer *new_buff;
1209 	u16 nta = rx_ring->next_to_alloc;
1210 
1211 	new_buff = &rx_ring->rx_bi[nta];
1212 
1213 	/* update, and store next to alloc */
1214 	nta++;
1215 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
1216 
1217 	/* transfer page from old buffer to new buffer */
1218 	new_buff->dma		= old_buff->dma;
1219 	new_buff->page		= old_buff->page;
1220 	new_buff->page_offset	= old_buff->page_offset;
1221 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
1222 
1223 	rx_ring->rx_stats.page_reuse_count++;
1224 
1225 	/* clear contents of buffer_info */
1226 	old_buff->page = NULL;
1227 }
1228 
1229 /**
1230  * i40e_rx_is_programming_status - check for programming status descriptor
1231  * @qw: qword representing status_error_len in CPU ordering
1232  *
1233  * The value of in the descriptor length field indicate if this
1234  * is a programming status descriptor for flow director or FCoE
1235  * by the value of I40E_RX_PROG_STATUS_DESC_LENGTH, otherwise
1236  * it is a packet descriptor.
1237  **/
1238 static inline bool i40e_rx_is_programming_status(u64 qw)
1239 {
1240 	/* The Rx filter programming status and SPH bit occupy the same
1241 	 * spot in the descriptor. Since we don't support packet split we
1242 	 * can just reuse the bit as an indication that this is a
1243 	 * programming status descriptor.
1244 	 */
1245 	return qw & I40E_RXD_QW1_LENGTH_SPH_MASK;
1246 }
1247 
1248 /**
1249  * i40e_clean_programming_status - try clean the programming status descriptor
1250  * @rx_ring: the rx ring that has this descriptor
1251  * @rx_desc: the rx descriptor written back by HW
1252  * @qw: qword representing status_error_len in CPU ordering
1253  *
1254  * Flow director should handle FD_FILTER_STATUS to check its filter programming
1255  * status being successful or not and take actions accordingly. FCoE should
1256  * handle its context/filter programming/invalidation status and take actions.
1257  *
1258  * Returns an i40e_rx_buffer to reuse if the cleanup occurred, otherwise NULL.
1259  **/
1260 struct i40e_rx_buffer *i40e_clean_programming_status(
1261 	struct i40e_ring *rx_ring,
1262 	union i40e_rx_desc *rx_desc,
1263 	u64 qw)
1264 {
1265 	struct i40e_rx_buffer *rx_buffer;
1266 	u32 ntc;
1267 	u8 id;
1268 
1269 	if (!i40e_rx_is_programming_status(qw))
1270 		return NULL;
1271 
1272 	ntc = rx_ring->next_to_clean;
1273 
1274 	/* fetch, update, and store next to clean */
1275 	rx_buffer = &rx_ring->rx_bi[ntc++];
1276 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1277 	rx_ring->next_to_clean = ntc;
1278 
1279 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1280 
1281 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
1282 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
1283 
1284 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
1285 		i40e_fd_handle_status(rx_ring, rx_desc, id);
1286 
1287 	return rx_buffer;
1288 }
1289 
1290 /**
1291  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
1292  * @tx_ring: the tx ring to set up
1293  *
1294  * Return 0 on success, negative on error
1295  **/
1296 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
1297 {
1298 	struct device *dev = tx_ring->dev;
1299 	int bi_size;
1300 
1301 	if (!dev)
1302 		return -ENOMEM;
1303 
1304 	/* warn if we are about to overwrite the pointer */
1305 	WARN_ON(tx_ring->tx_bi);
1306 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
1307 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
1308 	if (!tx_ring->tx_bi)
1309 		goto err;
1310 
1311 	u64_stats_init(&tx_ring->syncp);
1312 
1313 	/* round up to nearest 4K */
1314 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
1315 	/* add u32 for head writeback, align after this takes care of
1316 	 * guaranteeing this is at least one cache line in size
1317 	 */
1318 	tx_ring->size += sizeof(u32);
1319 	tx_ring->size = ALIGN(tx_ring->size, 4096);
1320 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
1321 					   &tx_ring->dma, GFP_KERNEL);
1322 	if (!tx_ring->desc) {
1323 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
1324 			 tx_ring->size);
1325 		goto err;
1326 	}
1327 
1328 	tx_ring->next_to_use = 0;
1329 	tx_ring->next_to_clean = 0;
1330 	tx_ring->tx_stats.prev_pkt_ctr = -1;
1331 	return 0;
1332 
1333 err:
1334 	kfree(tx_ring->tx_bi);
1335 	tx_ring->tx_bi = NULL;
1336 	return -ENOMEM;
1337 }
1338 
1339 /**
1340  * i40e_clean_rx_ring - Free Rx buffers
1341  * @rx_ring: ring to be cleaned
1342  **/
1343 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1344 {
1345 	unsigned long bi_size;
1346 	u16 i;
1347 
1348 	/* ring already cleared, nothing to do */
1349 	if (!rx_ring->rx_bi)
1350 		return;
1351 
1352 	if (rx_ring->skb) {
1353 		dev_kfree_skb(rx_ring->skb);
1354 		rx_ring->skb = NULL;
1355 	}
1356 
1357 	if (rx_ring->xsk_umem) {
1358 		i40e_xsk_clean_rx_ring(rx_ring);
1359 		goto skip_free;
1360 	}
1361 
1362 	/* Free all the Rx ring sk_buffs */
1363 	for (i = 0; i < rx_ring->count; i++) {
1364 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
1365 
1366 		if (!rx_bi->page)
1367 			continue;
1368 
1369 		/* Invalidate cache lines that may have been written to by
1370 		 * device so that we avoid corrupting memory.
1371 		 */
1372 		dma_sync_single_range_for_cpu(rx_ring->dev,
1373 					      rx_bi->dma,
1374 					      rx_bi->page_offset,
1375 					      rx_ring->rx_buf_len,
1376 					      DMA_FROM_DEVICE);
1377 
1378 		/* free resources associated with mapping */
1379 		dma_unmap_page_attrs(rx_ring->dev, rx_bi->dma,
1380 				     i40e_rx_pg_size(rx_ring),
1381 				     DMA_FROM_DEVICE,
1382 				     I40E_RX_DMA_ATTR);
1383 
1384 		__page_frag_cache_drain(rx_bi->page, rx_bi->pagecnt_bias);
1385 
1386 		rx_bi->page = NULL;
1387 		rx_bi->page_offset = 0;
1388 	}
1389 
1390 skip_free:
1391 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1392 	memset(rx_ring->rx_bi, 0, bi_size);
1393 
1394 	/* Zero out the descriptor ring */
1395 	memset(rx_ring->desc, 0, rx_ring->size);
1396 
1397 	rx_ring->next_to_alloc = 0;
1398 	rx_ring->next_to_clean = 0;
1399 	rx_ring->next_to_use = 0;
1400 }
1401 
1402 /**
1403  * i40e_free_rx_resources - Free Rx resources
1404  * @rx_ring: ring to clean the resources from
1405  *
1406  * Free all receive software resources
1407  **/
1408 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1409 {
1410 	i40e_clean_rx_ring(rx_ring);
1411 	if (rx_ring->vsi->type == I40E_VSI_MAIN)
1412 		xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
1413 	rx_ring->xdp_prog = NULL;
1414 	kfree(rx_ring->rx_bi);
1415 	rx_ring->rx_bi = NULL;
1416 
1417 	if (rx_ring->desc) {
1418 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1419 				  rx_ring->desc, rx_ring->dma);
1420 		rx_ring->desc = NULL;
1421 	}
1422 }
1423 
1424 /**
1425  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1426  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1427  *
1428  * Returns 0 on success, negative on failure
1429  **/
1430 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1431 {
1432 	struct device *dev = rx_ring->dev;
1433 	int err = -ENOMEM;
1434 	int bi_size;
1435 
1436 	/* warn if we are about to overwrite the pointer */
1437 	WARN_ON(rx_ring->rx_bi);
1438 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1439 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1440 	if (!rx_ring->rx_bi)
1441 		goto err;
1442 
1443 	u64_stats_init(&rx_ring->syncp);
1444 
1445 	/* Round up to nearest 4K */
1446 	rx_ring->size = rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1447 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1448 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1449 					   &rx_ring->dma, GFP_KERNEL);
1450 
1451 	if (!rx_ring->desc) {
1452 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1453 			 rx_ring->size);
1454 		goto err;
1455 	}
1456 
1457 	rx_ring->next_to_alloc = 0;
1458 	rx_ring->next_to_clean = 0;
1459 	rx_ring->next_to_use = 0;
1460 
1461 	/* XDP RX-queue info only needed for RX rings exposed to XDP */
1462 	if (rx_ring->vsi->type == I40E_VSI_MAIN) {
1463 		err = xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
1464 				       rx_ring->queue_index);
1465 		if (err < 0)
1466 			goto err;
1467 	}
1468 
1469 	rx_ring->xdp_prog = rx_ring->vsi->xdp_prog;
1470 
1471 	return 0;
1472 err:
1473 	kfree(rx_ring->rx_bi);
1474 	rx_ring->rx_bi = NULL;
1475 	return err;
1476 }
1477 
1478 /**
1479  * i40e_release_rx_desc - Store the new tail and head values
1480  * @rx_ring: ring to bump
1481  * @val: new head index
1482  **/
1483 void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1484 {
1485 	rx_ring->next_to_use = val;
1486 
1487 	/* update next to alloc since we have filled the ring */
1488 	rx_ring->next_to_alloc = val;
1489 
1490 	/* Force memory writes to complete before letting h/w
1491 	 * know there are new descriptors to fetch.  (Only
1492 	 * applicable for weak-ordered memory model archs,
1493 	 * such as IA-64).
1494 	 */
1495 	wmb();
1496 	writel(val, rx_ring->tail);
1497 }
1498 
1499 /**
1500  * i40e_rx_offset - Return expected offset into page to access data
1501  * @rx_ring: Ring we are requesting offset of
1502  *
1503  * Returns the offset value for ring into the data buffer.
1504  */
1505 static inline unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
1506 {
1507 	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
1508 }
1509 
1510 /**
1511  * i40e_alloc_mapped_page - recycle or make a new page
1512  * @rx_ring: ring to use
1513  * @bi: rx_buffer struct to modify
1514  *
1515  * Returns true if the page was successfully allocated or
1516  * reused.
1517  **/
1518 static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
1519 				   struct i40e_rx_buffer *bi)
1520 {
1521 	struct page *page = bi->page;
1522 	dma_addr_t dma;
1523 
1524 	/* since we are recycling buffers we should seldom need to alloc */
1525 	if (likely(page)) {
1526 		rx_ring->rx_stats.page_reuse_count++;
1527 		return true;
1528 	}
1529 
1530 	/* alloc new page for storage */
1531 	page = dev_alloc_pages(i40e_rx_pg_order(rx_ring));
1532 	if (unlikely(!page)) {
1533 		rx_ring->rx_stats.alloc_page_failed++;
1534 		return false;
1535 	}
1536 
1537 	/* map page for use */
1538 	dma = dma_map_page_attrs(rx_ring->dev, page, 0,
1539 				 i40e_rx_pg_size(rx_ring),
1540 				 DMA_FROM_DEVICE,
1541 				 I40E_RX_DMA_ATTR);
1542 
1543 	/* if mapping failed free memory back to system since
1544 	 * there isn't much point in holding memory we can't use
1545 	 */
1546 	if (dma_mapping_error(rx_ring->dev, dma)) {
1547 		__free_pages(page, i40e_rx_pg_order(rx_ring));
1548 		rx_ring->rx_stats.alloc_page_failed++;
1549 		return false;
1550 	}
1551 
1552 	bi->dma = dma;
1553 	bi->page = page;
1554 	bi->page_offset = i40e_rx_offset(rx_ring);
1555 	page_ref_add(page, USHRT_MAX - 1);
1556 	bi->pagecnt_bias = USHRT_MAX;
1557 
1558 	return true;
1559 }
1560 
1561 /**
1562  * i40e_alloc_rx_buffers - Replace used receive buffers
1563  * @rx_ring: ring to place buffers on
1564  * @cleaned_count: number of buffers to replace
1565  *
1566  * Returns false if all allocations were successful, true if any fail
1567  **/
1568 bool i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1569 {
1570 	u16 ntu = rx_ring->next_to_use;
1571 	union i40e_rx_desc *rx_desc;
1572 	struct i40e_rx_buffer *bi;
1573 
1574 	/* do nothing if no valid netdev defined */
1575 	if (!rx_ring->netdev || !cleaned_count)
1576 		return false;
1577 
1578 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
1579 	bi = &rx_ring->rx_bi[ntu];
1580 
1581 	do {
1582 		if (!i40e_alloc_mapped_page(rx_ring, bi))
1583 			goto no_buffers;
1584 
1585 		/* sync the buffer for use by the device */
1586 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
1587 						 bi->page_offset,
1588 						 rx_ring->rx_buf_len,
1589 						 DMA_FROM_DEVICE);
1590 
1591 		/* Refresh the desc even if buffer_addrs didn't change
1592 		 * because each write-back erases this info.
1593 		 */
1594 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
1595 
1596 		rx_desc++;
1597 		bi++;
1598 		ntu++;
1599 		if (unlikely(ntu == rx_ring->count)) {
1600 			rx_desc = I40E_RX_DESC(rx_ring, 0);
1601 			bi = rx_ring->rx_bi;
1602 			ntu = 0;
1603 		}
1604 
1605 		/* clear the status bits for the next_to_use descriptor */
1606 		rx_desc->wb.qword1.status_error_len = 0;
1607 
1608 		cleaned_count--;
1609 	} while (cleaned_count);
1610 
1611 	if (rx_ring->next_to_use != ntu)
1612 		i40e_release_rx_desc(rx_ring, ntu);
1613 
1614 	return false;
1615 
1616 no_buffers:
1617 	if (rx_ring->next_to_use != ntu)
1618 		i40e_release_rx_desc(rx_ring, ntu);
1619 
1620 	/* make sure to come back via polling to try again after
1621 	 * allocation failure
1622 	 */
1623 	return true;
1624 }
1625 
1626 /**
1627  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1628  * @vsi: the VSI we care about
1629  * @skb: skb currently being received and modified
1630  * @rx_desc: the receive descriptor
1631  **/
1632 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1633 				    struct sk_buff *skb,
1634 				    union i40e_rx_desc *rx_desc)
1635 {
1636 	struct i40e_rx_ptype_decoded decoded;
1637 	u32 rx_error, rx_status;
1638 	bool ipv4, ipv6;
1639 	u8 ptype;
1640 	u64 qword;
1641 
1642 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1643 	ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >> I40E_RXD_QW1_PTYPE_SHIFT;
1644 	rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1645 		   I40E_RXD_QW1_ERROR_SHIFT;
1646 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1647 		    I40E_RXD_QW1_STATUS_SHIFT;
1648 	decoded = decode_rx_desc_ptype(ptype);
1649 
1650 	skb->ip_summed = CHECKSUM_NONE;
1651 
1652 	skb_checksum_none_assert(skb);
1653 
1654 	/* Rx csum enabled and ip headers found? */
1655 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1656 		return;
1657 
1658 	/* did the hardware decode the packet and checksum? */
1659 	if (!(rx_status & BIT(I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1660 		return;
1661 
1662 	/* both known and outer_ip must be set for the below code to work */
1663 	if (!(decoded.known && decoded.outer_ip))
1664 		return;
1665 
1666 	ipv4 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1667 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4);
1668 	ipv6 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1669 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6);
1670 
1671 	if (ipv4 &&
1672 	    (rx_error & (BIT(I40E_RX_DESC_ERROR_IPE_SHIFT) |
1673 			 BIT(I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1674 		goto checksum_fail;
1675 
1676 	/* likely incorrect csum if alternate IP extension headers found */
1677 	if (ipv6 &&
1678 	    rx_status & BIT(I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1679 		/* don't increment checksum err here, non-fatal err */
1680 		return;
1681 
1682 	/* there was some L4 error, count error and punt packet to the stack */
1683 	if (rx_error & BIT(I40E_RX_DESC_ERROR_L4E_SHIFT))
1684 		goto checksum_fail;
1685 
1686 	/* handle packets that were not able to be checksummed due
1687 	 * to arrival speed, in this case the stack can compute
1688 	 * the csum.
1689 	 */
1690 	if (rx_error & BIT(I40E_RX_DESC_ERROR_PPRS_SHIFT))
1691 		return;
1692 
1693 	/* If there is an outer header present that might contain a checksum
1694 	 * we need to bump the checksum level by 1 to reflect the fact that
1695 	 * we are indicating we validated the inner checksum.
1696 	 */
1697 	if (decoded.tunnel_type >= I40E_RX_PTYPE_TUNNEL_IP_GRENAT)
1698 		skb->csum_level = 1;
1699 
1700 	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
1701 	switch (decoded.inner_prot) {
1702 	case I40E_RX_PTYPE_INNER_PROT_TCP:
1703 	case I40E_RX_PTYPE_INNER_PROT_UDP:
1704 	case I40E_RX_PTYPE_INNER_PROT_SCTP:
1705 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1706 		/* fall though */
1707 	default:
1708 		break;
1709 	}
1710 
1711 	return;
1712 
1713 checksum_fail:
1714 	vsi->back->hw_csum_rx_error++;
1715 }
1716 
1717 /**
1718  * i40e_ptype_to_htype - get a hash type
1719  * @ptype: the ptype value from the descriptor
1720  *
1721  * Returns a hash type to be used by skb_set_hash
1722  **/
1723 static inline int i40e_ptype_to_htype(u8 ptype)
1724 {
1725 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1726 
1727 	if (!decoded.known)
1728 		return PKT_HASH_TYPE_NONE;
1729 
1730 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1731 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1732 		return PKT_HASH_TYPE_L4;
1733 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1734 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1735 		return PKT_HASH_TYPE_L3;
1736 	else
1737 		return PKT_HASH_TYPE_L2;
1738 }
1739 
1740 /**
1741  * i40e_rx_hash - set the hash value in the skb
1742  * @ring: descriptor ring
1743  * @rx_desc: specific descriptor
1744  * @skb: skb currently being received and modified
1745  * @rx_ptype: Rx packet type
1746  **/
1747 static inline void i40e_rx_hash(struct i40e_ring *ring,
1748 				union i40e_rx_desc *rx_desc,
1749 				struct sk_buff *skb,
1750 				u8 rx_ptype)
1751 {
1752 	u32 hash;
1753 	const __le64 rss_mask =
1754 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1755 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1756 
1757 	if (!(ring->netdev->features & NETIF_F_RXHASH))
1758 		return;
1759 
1760 	if ((rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask) {
1761 		hash = le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1762 		skb_set_hash(skb, hash, i40e_ptype_to_htype(rx_ptype));
1763 	}
1764 }
1765 
1766 /**
1767  * i40e_process_skb_fields - Populate skb header fields from Rx descriptor
1768  * @rx_ring: rx descriptor ring packet is being transacted on
1769  * @rx_desc: pointer to the EOP Rx descriptor
1770  * @skb: pointer to current skb being populated
1771  * @rx_ptype: the packet type decoded by hardware
1772  *
1773  * This function checks the ring, descriptor, and packet information in
1774  * order to populate the hash, checksum, VLAN, protocol, and
1775  * other fields within the skb.
1776  **/
1777 void i40e_process_skb_fields(struct i40e_ring *rx_ring,
1778 			     union i40e_rx_desc *rx_desc, struct sk_buff *skb)
1779 {
1780 	u64 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1781 	u32 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1782 			I40E_RXD_QW1_STATUS_SHIFT;
1783 	u32 tsynvalid = rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK;
1784 	u32 tsyn = (rx_status & I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1785 		   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT;
1786 	u8 rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1787 		      I40E_RXD_QW1_PTYPE_SHIFT;
1788 
1789 	if (unlikely(tsynvalid))
1790 		i40e_ptp_rx_hwtstamp(rx_ring->vsi->back, skb, tsyn);
1791 
1792 	i40e_rx_hash(rx_ring, rx_desc, skb, rx_ptype);
1793 
1794 	i40e_rx_checksum(rx_ring->vsi, skb, rx_desc);
1795 
1796 	skb_record_rx_queue(skb, rx_ring->queue_index);
1797 
1798 	if (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) {
1799 		u16 vlan_tag = rx_desc->wb.qword0.lo_dword.l2tag1;
1800 
1801 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
1802 				       le16_to_cpu(vlan_tag));
1803 	}
1804 
1805 	/* modifies the skb - consumes the enet header */
1806 	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1807 }
1808 
1809 /**
1810  * i40e_cleanup_headers - Correct empty headers
1811  * @rx_ring: rx descriptor ring packet is being transacted on
1812  * @skb: pointer to current skb being fixed
1813  * @rx_desc: pointer to the EOP Rx descriptor
1814  *
1815  * Also address the case where we are pulling data in on pages only
1816  * and as such no data is present in the skb header.
1817  *
1818  * In addition if skb is not at least 60 bytes we need to pad it so that
1819  * it is large enough to qualify as a valid Ethernet frame.
1820  *
1821  * Returns true if an error was encountered and skb was freed.
1822  **/
1823 static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
1824 				 union i40e_rx_desc *rx_desc)
1825 
1826 {
1827 	/* XDP packets use error pointer so abort at this point */
1828 	if (IS_ERR(skb))
1829 		return true;
1830 
1831 	/* ERR_MASK will only have valid bits if EOP set, and
1832 	 * what we are doing here is actually checking
1833 	 * I40E_RX_DESC_ERROR_RXE_SHIFT, since it is the zeroth bit in
1834 	 * the error field
1835 	 */
1836 	if (unlikely(i40e_test_staterr(rx_desc,
1837 				       BIT(I40E_RXD_QW1_ERROR_SHIFT)))) {
1838 		dev_kfree_skb_any(skb);
1839 		return true;
1840 	}
1841 
1842 	/* if eth_skb_pad returns an error the skb was freed */
1843 	if (eth_skb_pad(skb))
1844 		return true;
1845 
1846 	return false;
1847 }
1848 
1849 /**
1850  * i40e_page_is_reusable - check if any reuse is possible
1851  * @page: page struct to check
1852  *
1853  * A page is not reusable if it was allocated under low memory
1854  * conditions, or it's not in the same NUMA node as this CPU.
1855  */
1856 static inline bool i40e_page_is_reusable(struct page *page)
1857 {
1858 	return (page_to_nid(page) == numa_mem_id()) &&
1859 		!page_is_pfmemalloc(page);
1860 }
1861 
1862 /**
1863  * i40e_can_reuse_rx_page - Determine if this page can be reused by
1864  * the adapter for another receive
1865  *
1866  * @rx_buffer: buffer containing the page
1867  *
1868  * If page is reusable, rx_buffer->page_offset is adjusted to point to
1869  * an unused region in the page.
1870  *
1871  * For small pages, @truesize will be a constant value, half the size
1872  * of the memory at page.  We'll attempt to alternate between high and
1873  * low halves of the page, with one half ready for use by the hardware
1874  * and the other half being consumed by the stack.  We use the page
1875  * ref count to determine whether the stack has finished consuming the
1876  * portion of this page that was passed up with a previous packet.  If
1877  * the page ref count is >1, we'll assume the "other" half page is
1878  * still busy, and this page cannot be reused.
1879  *
1880  * For larger pages, @truesize will be the actual space used by the
1881  * received packet (adjusted upward to an even multiple of the cache
1882  * line size).  This will advance through the page by the amount
1883  * actually consumed by the received packets while there is still
1884  * space for a buffer.  Each region of larger pages will be used at
1885  * most once, after which the page will not be reused.
1886  *
1887  * In either case, if the page is reusable its refcount is increased.
1888  **/
1889 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer)
1890 {
1891 	unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
1892 	struct page *page = rx_buffer->page;
1893 
1894 	/* Is any reuse possible? */
1895 	if (unlikely(!i40e_page_is_reusable(page)))
1896 		return false;
1897 
1898 #if (PAGE_SIZE < 8192)
1899 	/* if we are only owner of page we can reuse it */
1900 	if (unlikely((page_count(page) - pagecnt_bias) > 1))
1901 		return false;
1902 #else
1903 #define I40E_LAST_OFFSET \
1904 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - I40E_RXBUFFER_2048)
1905 	if (rx_buffer->page_offset > I40E_LAST_OFFSET)
1906 		return false;
1907 #endif
1908 
1909 	/* If we have drained the page fragment pool we need to update
1910 	 * the pagecnt_bias and page count so that we fully restock the
1911 	 * number of references the driver holds.
1912 	 */
1913 	if (unlikely(pagecnt_bias == 1)) {
1914 		page_ref_add(page, USHRT_MAX - 1);
1915 		rx_buffer->pagecnt_bias = USHRT_MAX;
1916 	}
1917 
1918 	return true;
1919 }
1920 
1921 /**
1922  * i40e_add_rx_frag - Add contents of Rx buffer to sk_buff
1923  * @rx_ring: rx descriptor ring to transact packets on
1924  * @rx_buffer: buffer containing page to add
1925  * @skb: sk_buff to place the data into
1926  * @size: packet length from rx_desc
1927  *
1928  * This function will add the data contained in rx_buffer->page to the skb.
1929  * It will just attach the page as a frag to the skb.
1930  *
1931  * The function will then update the page offset.
1932  **/
1933 static void i40e_add_rx_frag(struct i40e_ring *rx_ring,
1934 			     struct i40e_rx_buffer *rx_buffer,
1935 			     struct sk_buff *skb,
1936 			     unsigned int size)
1937 {
1938 #if (PAGE_SIZE < 8192)
1939 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1940 #else
1941 	unsigned int truesize = SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring));
1942 #endif
1943 
1944 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
1945 			rx_buffer->page_offset, size, truesize);
1946 
1947 	/* page is being used so we must update the page offset */
1948 #if (PAGE_SIZE < 8192)
1949 	rx_buffer->page_offset ^= truesize;
1950 #else
1951 	rx_buffer->page_offset += truesize;
1952 #endif
1953 }
1954 
1955 /**
1956  * i40e_get_rx_buffer - Fetch Rx buffer and synchronize data for use
1957  * @rx_ring: rx descriptor ring to transact packets on
1958  * @size: size of buffer to add to skb
1959  *
1960  * This function will pull an Rx buffer from the ring and synchronize it
1961  * for use by the CPU.
1962  */
1963 static struct i40e_rx_buffer *i40e_get_rx_buffer(struct i40e_ring *rx_ring,
1964 						 const unsigned int size)
1965 {
1966 	struct i40e_rx_buffer *rx_buffer;
1967 
1968 	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
1969 	prefetchw(rx_buffer->page);
1970 
1971 	/* we are reusing so sync this buffer for CPU use */
1972 	dma_sync_single_range_for_cpu(rx_ring->dev,
1973 				      rx_buffer->dma,
1974 				      rx_buffer->page_offset,
1975 				      size,
1976 				      DMA_FROM_DEVICE);
1977 
1978 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
1979 	rx_buffer->pagecnt_bias--;
1980 
1981 	return rx_buffer;
1982 }
1983 
1984 /**
1985  * i40e_construct_skb - Allocate skb and populate it
1986  * @rx_ring: rx descriptor ring to transact packets on
1987  * @rx_buffer: rx buffer to pull data from
1988  * @xdp: xdp_buff pointing to the data
1989  *
1990  * This function allocates an skb.  It then populates it with the page
1991  * data from the current receive descriptor, taking care to set up the
1992  * skb correctly.
1993  */
1994 static struct sk_buff *i40e_construct_skb(struct i40e_ring *rx_ring,
1995 					  struct i40e_rx_buffer *rx_buffer,
1996 					  struct xdp_buff *xdp)
1997 {
1998 	unsigned int size = xdp->data_end - xdp->data;
1999 #if (PAGE_SIZE < 8192)
2000 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
2001 #else
2002 	unsigned int truesize = SKB_DATA_ALIGN(size);
2003 #endif
2004 	unsigned int headlen;
2005 	struct sk_buff *skb;
2006 
2007 	/* prefetch first cache line of first page */
2008 	prefetch(xdp->data);
2009 #if L1_CACHE_BYTES < 128
2010 	prefetch(xdp->data + L1_CACHE_BYTES);
2011 #endif
2012 	/* Note, we get here by enabling legacy-rx via:
2013 	 *
2014 	 *    ethtool --set-priv-flags <dev> legacy-rx on
2015 	 *
2016 	 * In this mode, we currently get 0 extra XDP headroom as
2017 	 * opposed to having legacy-rx off, where we process XDP
2018 	 * packets going to stack via i40e_build_skb(). The latter
2019 	 * provides us currently with 192 bytes of headroom.
2020 	 *
2021 	 * For i40e_construct_skb() mode it means that the
2022 	 * xdp->data_meta will always point to xdp->data, since
2023 	 * the helper cannot expand the head. Should this ever
2024 	 * change in future for legacy-rx mode on, then lets also
2025 	 * add xdp->data_meta handling here.
2026 	 */
2027 
2028 	/* allocate a skb to store the frags */
2029 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
2030 			       I40E_RX_HDR_SIZE,
2031 			       GFP_ATOMIC | __GFP_NOWARN);
2032 	if (unlikely(!skb))
2033 		return NULL;
2034 
2035 	/* Determine available headroom for copy */
2036 	headlen = size;
2037 	if (headlen > I40E_RX_HDR_SIZE)
2038 		headlen = eth_get_headlen(skb->dev, xdp->data,
2039 					  I40E_RX_HDR_SIZE);
2040 
2041 	/* align pull length to size of long to optimize memcpy performance */
2042 	memcpy(__skb_put(skb, headlen), xdp->data,
2043 	       ALIGN(headlen, sizeof(long)));
2044 
2045 	/* update all of the pointers */
2046 	size -= headlen;
2047 	if (size) {
2048 		skb_add_rx_frag(skb, 0, rx_buffer->page,
2049 				rx_buffer->page_offset + headlen,
2050 				size, truesize);
2051 
2052 		/* buffer is used by skb, update page_offset */
2053 #if (PAGE_SIZE < 8192)
2054 		rx_buffer->page_offset ^= truesize;
2055 #else
2056 		rx_buffer->page_offset += truesize;
2057 #endif
2058 	} else {
2059 		/* buffer is unused, reset bias back to rx_buffer */
2060 		rx_buffer->pagecnt_bias++;
2061 	}
2062 
2063 	return skb;
2064 }
2065 
2066 /**
2067  * i40e_build_skb - Build skb around an existing buffer
2068  * @rx_ring: Rx descriptor ring to transact packets on
2069  * @rx_buffer: Rx buffer to pull data from
2070  * @xdp: xdp_buff pointing to the data
2071  *
2072  * This function builds an skb around an existing Rx buffer, taking care
2073  * to set up the skb correctly and avoid any memcpy overhead.
2074  */
2075 static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
2076 				      struct i40e_rx_buffer *rx_buffer,
2077 				      struct xdp_buff *xdp)
2078 {
2079 	unsigned int metasize = xdp->data - xdp->data_meta;
2080 #if (PAGE_SIZE < 8192)
2081 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
2082 #else
2083 	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
2084 				SKB_DATA_ALIGN(xdp->data_end -
2085 					       xdp->data_hard_start);
2086 #endif
2087 	struct sk_buff *skb;
2088 
2089 	/* Prefetch first cache line of first page. If xdp->data_meta
2090 	 * is unused, this points exactly as xdp->data, otherwise we
2091 	 * likely have a consumer accessing first few bytes of meta
2092 	 * data, and then actual data.
2093 	 */
2094 	prefetch(xdp->data_meta);
2095 #if L1_CACHE_BYTES < 128
2096 	prefetch(xdp->data_meta + L1_CACHE_BYTES);
2097 #endif
2098 	/* build an skb around the page buffer */
2099 	skb = build_skb(xdp->data_hard_start, truesize);
2100 	if (unlikely(!skb))
2101 		return NULL;
2102 
2103 	/* update pointers within the skb to store the data */
2104 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
2105 	__skb_put(skb, xdp->data_end - xdp->data);
2106 	if (metasize)
2107 		skb_metadata_set(skb, metasize);
2108 
2109 	/* buffer is used by skb, update page_offset */
2110 #if (PAGE_SIZE < 8192)
2111 	rx_buffer->page_offset ^= truesize;
2112 #else
2113 	rx_buffer->page_offset += truesize;
2114 #endif
2115 
2116 	return skb;
2117 }
2118 
2119 /**
2120  * i40e_put_rx_buffer - Clean up used buffer and either recycle or free
2121  * @rx_ring: rx descriptor ring to transact packets on
2122  * @rx_buffer: rx buffer to pull data from
2123  *
2124  * This function will clean up the contents of the rx_buffer.  It will
2125  * either recycle the buffer or unmap it and free the associated resources.
2126  */
2127 static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
2128 			       struct i40e_rx_buffer *rx_buffer)
2129 {
2130 	if (i40e_can_reuse_rx_page(rx_buffer)) {
2131 		/* hand second half of page back to the ring */
2132 		i40e_reuse_rx_page(rx_ring, rx_buffer);
2133 	} else {
2134 		/* we are not reusing the buffer so unmap it */
2135 		dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
2136 				     i40e_rx_pg_size(rx_ring),
2137 				     DMA_FROM_DEVICE, I40E_RX_DMA_ATTR);
2138 		__page_frag_cache_drain(rx_buffer->page,
2139 					rx_buffer->pagecnt_bias);
2140 		/* clear contents of buffer_info */
2141 		rx_buffer->page = NULL;
2142 	}
2143 }
2144 
2145 /**
2146  * i40e_is_non_eop - process handling of non-EOP buffers
2147  * @rx_ring: Rx ring being processed
2148  * @rx_desc: Rx descriptor for current buffer
2149  * @skb: Current socket buffer containing buffer in progress
2150  *
2151  * This function updates next to clean.  If the buffer is an EOP buffer
2152  * this function exits returning false, otherwise it will place the
2153  * sk_buff in the next buffer to be chained and return true indicating
2154  * that this is in fact a non-EOP buffer.
2155  **/
2156 static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
2157 			    union i40e_rx_desc *rx_desc,
2158 			    struct sk_buff *skb)
2159 {
2160 	u32 ntc = rx_ring->next_to_clean + 1;
2161 
2162 	/* fetch, update, and store next to clean */
2163 	ntc = (ntc < rx_ring->count) ? ntc : 0;
2164 	rx_ring->next_to_clean = ntc;
2165 
2166 	prefetch(I40E_RX_DESC(rx_ring, ntc));
2167 
2168 	/* if we are the last buffer then there is nothing else to do */
2169 #define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
2170 	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))
2171 		return false;
2172 
2173 	rx_ring->rx_stats.non_eop_descs++;
2174 
2175 	return true;
2176 }
2177 
2178 static int i40e_xmit_xdp_ring(struct xdp_frame *xdpf,
2179 			      struct i40e_ring *xdp_ring);
2180 
2181 int i40e_xmit_xdp_tx_ring(struct xdp_buff *xdp, struct i40e_ring *xdp_ring)
2182 {
2183 	struct xdp_frame *xdpf = convert_to_xdp_frame(xdp);
2184 
2185 	if (unlikely(!xdpf))
2186 		return I40E_XDP_CONSUMED;
2187 
2188 	return i40e_xmit_xdp_ring(xdpf, xdp_ring);
2189 }
2190 
2191 /**
2192  * i40e_run_xdp - run an XDP program
2193  * @rx_ring: Rx ring being processed
2194  * @xdp: XDP buffer containing the frame
2195  **/
2196 static struct sk_buff *i40e_run_xdp(struct i40e_ring *rx_ring,
2197 				    struct xdp_buff *xdp)
2198 {
2199 	int err, result = I40E_XDP_PASS;
2200 	struct i40e_ring *xdp_ring;
2201 	struct bpf_prog *xdp_prog;
2202 	u32 act;
2203 
2204 	rcu_read_lock();
2205 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
2206 
2207 	if (!xdp_prog)
2208 		goto xdp_out;
2209 
2210 	prefetchw(xdp->data_hard_start); /* xdp_frame write */
2211 
2212 	act = bpf_prog_run_xdp(xdp_prog, xdp);
2213 	switch (act) {
2214 	case XDP_PASS:
2215 		break;
2216 	case XDP_TX:
2217 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2218 		result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
2219 		break;
2220 	case XDP_REDIRECT:
2221 		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
2222 		result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
2223 		break;
2224 	default:
2225 		bpf_warn_invalid_xdp_action(act);
2226 		/* fall through */
2227 	case XDP_ABORTED:
2228 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
2229 		/* fall through -- handle aborts by dropping packet */
2230 	case XDP_DROP:
2231 		result = I40E_XDP_CONSUMED;
2232 		break;
2233 	}
2234 xdp_out:
2235 	rcu_read_unlock();
2236 	return ERR_PTR(-result);
2237 }
2238 
2239 /**
2240  * i40e_rx_buffer_flip - adjusted rx_buffer to point to an unused region
2241  * @rx_ring: Rx ring
2242  * @rx_buffer: Rx buffer to adjust
2243  * @size: Size of adjustment
2244  **/
2245 static void i40e_rx_buffer_flip(struct i40e_ring *rx_ring,
2246 				struct i40e_rx_buffer *rx_buffer,
2247 				unsigned int size)
2248 {
2249 #if (PAGE_SIZE < 8192)
2250 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
2251 
2252 	rx_buffer->page_offset ^= truesize;
2253 #else
2254 	unsigned int truesize = SKB_DATA_ALIGN(i40e_rx_offset(rx_ring) + size);
2255 
2256 	rx_buffer->page_offset += truesize;
2257 #endif
2258 }
2259 
2260 /**
2261  * i40e_xdp_ring_update_tail - Updates the XDP Tx ring tail register
2262  * @xdp_ring: XDP Tx ring
2263  *
2264  * This function updates the XDP Tx ring tail register.
2265  **/
2266 void i40e_xdp_ring_update_tail(struct i40e_ring *xdp_ring)
2267 {
2268 	/* Force memory writes to complete before letting h/w
2269 	 * know there are new descriptors to fetch.
2270 	 */
2271 	wmb();
2272 	writel_relaxed(xdp_ring->next_to_use, xdp_ring->tail);
2273 }
2274 
2275 /**
2276  * i40e_update_rx_stats - Update Rx ring statistics
2277  * @rx_ring: rx descriptor ring
2278  * @total_rx_bytes: number of bytes received
2279  * @total_rx_packets: number of packets received
2280  *
2281  * This function updates the Rx ring statistics.
2282  **/
2283 void i40e_update_rx_stats(struct i40e_ring *rx_ring,
2284 			  unsigned int total_rx_bytes,
2285 			  unsigned int total_rx_packets)
2286 {
2287 	u64_stats_update_begin(&rx_ring->syncp);
2288 	rx_ring->stats.packets += total_rx_packets;
2289 	rx_ring->stats.bytes += total_rx_bytes;
2290 	u64_stats_update_end(&rx_ring->syncp);
2291 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
2292 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
2293 }
2294 
2295 /**
2296  * i40e_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
2297  * @rx_ring: Rx ring
2298  * @xdp_res: Result of the receive batch
2299  *
2300  * This function bumps XDP Tx tail and/or flush redirect map, and
2301  * should be called when a batch of packets has been processed in the
2302  * napi loop.
2303  **/
2304 void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring, unsigned int xdp_res)
2305 {
2306 	if (xdp_res & I40E_XDP_REDIR)
2307 		xdp_do_flush_map();
2308 
2309 	if (xdp_res & I40E_XDP_TX) {
2310 		struct i40e_ring *xdp_ring =
2311 			rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2312 
2313 		i40e_xdp_ring_update_tail(xdp_ring);
2314 	}
2315 }
2316 
2317 /**
2318  * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
2319  * @rx_ring: rx descriptor ring to transact packets on
2320  * @budget: Total limit on number of packets to process
2321  *
2322  * This function provides a "bounce buffer" approach to Rx interrupt
2323  * processing.  The advantage to this is that on systems that have
2324  * expensive overhead for IOMMU access this provides a means of avoiding
2325  * it by maintaining the mapping of the page to the system.
2326  *
2327  * Returns amount of work completed
2328  **/
2329 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
2330 {
2331 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
2332 	struct sk_buff *skb = rx_ring->skb;
2333 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
2334 	unsigned int xdp_xmit = 0;
2335 	bool failure = false;
2336 	struct xdp_buff xdp;
2337 
2338 	xdp.rxq = &rx_ring->xdp_rxq;
2339 
2340 	while (likely(total_rx_packets < (unsigned int)budget)) {
2341 		struct i40e_rx_buffer *rx_buffer;
2342 		union i40e_rx_desc *rx_desc;
2343 		unsigned int size;
2344 		u64 qword;
2345 
2346 		/* return some buffers to hardware, one at a time is too slow */
2347 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
2348 			failure = failure ||
2349 				  i40e_alloc_rx_buffers(rx_ring, cleaned_count);
2350 			cleaned_count = 0;
2351 		}
2352 
2353 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
2354 
2355 		/* status_error_len will always be zero for unused descriptors
2356 		 * because it's cleared in cleanup, and overlaps with hdr_addr
2357 		 * which is always zero because packet split isn't used, if the
2358 		 * hardware wrote DD then the length will be non-zero
2359 		 */
2360 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2361 
2362 		/* This memory barrier is needed to keep us from reading
2363 		 * any other fields out of the rx_desc until we have
2364 		 * verified the descriptor has been written back.
2365 		 */
2366 		dma_rmb();
2367 
2368 		rx_buffer = i40e_clean_programming_status(rx_ring, rx_desc,
2369 							  qword);
2370 		if (unlikely(rx_buffer)) {
2371 			i40e_reuse_rx_page(rx_ring, rx_buffer);
2372 			cleaned_count++;
2373 			continue;
2374 		}
2375 
2376 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
2377 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
2378 		if (!size)
2379 			break;
2380 
2381 		i40e_trace(clean_rx_irq, rx_ring, rx_desc, skb);
2382 		rx_buffer = i40e_get_rx_buffer(rx_ring, size);
2383 
2384 		/* retrieve a buffer from the ring */
2385 		if (!skb) {
2386 			xdp.data = page_address(rx_buffer->page) +
2387 				   rx_buffer->page_offset;
2388 			xdp.data_meta = xdp.data;
2389 			xdp.data_hard_start = xdp.data -
2390 					      i40e_rx_offset(rx_ring);
2391 			xdp.data_end = xdp.data + size;
2392 
2393 			skb = i40e_run_xdp(rx_ring, &xdp);
2394 		}
2395 
2396 		if (IS_ERR(skb)) {
2397 			unsigned int xdp_res = -PTR_ERR(skb);
2398 
2399 			if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
2400 				xdp_xmit |= xdp_res;
2401 				i40e_rx_buffer_flip(rx_ring, rx_buffer, size);
2402 			} else {
2403 				rx_buffer->pagecnt_bias++;
2404 			}
2405 			total_rx_bytes += size;
2406 			total_rx_packets++;
2407 		} else if (skb) {
2408 			i40e_add_rx_frag(rx_ring, rx_buffer, skb, size);
2409 		} else if (ring_uses_build_skb(rx_ring)) {
2410 			skb = i40e_build_skb(rx_ring, rx_buffer, &xdp);
2411 		} else {
2412 			skb = i40e_construct_skb(rx_ring, rx_buffer, &xdp);
2413 		}
2414 
2415 		/* exit if we failed to retrieve a buffer */
2416 		if (!skb) {
2417 			rx_ring->rx_stats.alloc_buff_failed++;
2418 			rx_buffer->pagecnt_bias++;
2419 			break;
2420 		}
2421 
2422 		i40e_put_rx_buffer(rx_ring, rx_buffer);
2423 		cleaned_count++;
2424 
2425 		if (i40e_is_non_eop(rx_ring, rx_desc, skb))
2426 			continue;
2427 
2428 		if (i40e_cleanup_headers(rx_ring, skb, rx_desc)) {
2429 			skb = NULL;
2430 			continue;
2431 		}
2432 
2433 		/* probably a little skewed due to removing CRC */
2434 		total_rx_bytes += skb->len;
2435 
2436 		/* populate checksum, VLAN, and protocol */
2437 		i40e_process_skb_fields(rx_ring, rx_desc, skb);
2438 
2439 		i40e_trace(clean_rx_irq_rx, rx_ring, rx_desc, skb);
2440 		napi_gro_receive(&rx_ring->q_vector->napi, skb);
2441 		skb = NULL;
2442 
2443 		/* update budget accounting */
2444 		total_rx_packets++;
2445 	}
2446 
2447 	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
2448 	rx_ring->skb = skb;
2449 
2450 	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
2451 
2452 	/* guarantee a trip back through this routine if there was a failure */
2453 	return failure ? budget : (int)total_rx_packets;
2454 }
2455 
2456 static inline u32 i40e_buildreg_itr(const int type, u16 itr)
2457 {
2458 	u32 val;
2459 
2460 	/* We don't bother with setting the CLEARPBA bit as the data sheet
2461 	 * points out doing so is "meaningless since it was already
2462 	 * auto-cleared". The auto-clearing happens when the interrupt is
2463 	 * asserted.
2464 	 *
2465 	 * Hardware errata 28 for also indicates that writing to a
2466 	 * xxINT_DYN_CTLx CSR with INTENA_MSK (bit 31) set to 0 will clear
2467 	 * an event in the PBA anyway so we need to rely on the automask
2468 	 * to hold pending events for us until the interrupt is re-enabled
2469 	 *
2470 	 * The itr value is reported in microseconds, and the register
2471 	 * value is recorded in 2 microsecond units. For this reason we
2472 	 * only need to shift by the interval shift - 1 instead of the
2473 	 * full value.
2474 	 */
2475 	itr &= I40E_ITR_MASK;
2476 
2477 	val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
2478 	      (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
2479 	      (itr << (I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT - 1));
2480 
2481 	return val;
2482 }
2483 
2484 /* a small macro to shorten up some long lines */
2485 #define INTREG I40E_PFINT_DYN_CTLN
2486 
2487 /* The act of updating the ITR will cause it to immediately trigger. In order
2488  * to prevent this from throwing off adaptive update statistics we defer the
2489  * update so that it can only happen so often. So after either Tx or Rx are
2490  * updated we make the adaptive scheme wait until either the ITR completely
2491  * expires via the next_update expiration or we have been through at least
2492  * 3 interrupts.
2493  */
2494 #define ITR_COUNTDOWN_START 3
2495 
2496 /**
2497  * i40e_update_enable_itr - Update itr and re-enable MSIX interrupt
2498  * @vsi: the VSI we care about
2499  * @q_vector: q_vector for which itr is being updated and interrupt enabled
2500  *
2501  **/
2502 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
2503 					  struct i40e_q_vector *q_vector)
2504 {
2505 	struct i40e_hw *hw = &vsi->back->hw;
2506 	u32 intval;
2507 
2508 	/* If we don't have MSIX, then we only need to re-enable icr0 */
2509 	if (!(vsi->back->flags & I40E_FLAG_MSIX_ENABLED)) {
2510 		i40e_irq_dynamic_enable_icr0(vsi->back);
2511 		return;
2512 	}
2513 
2514 	/* These will do nothing if dynamic updates are not enabled */
2515 	i40e_update_itr(q_vector, &q_vector->tx);
2516 	i40e_update_itr(q_vector, &q_vector->rx);
2517 
2518 	/* This block of logic allows us to get away with only updating
2519 	 * one ITR value with each interrupt. The idea is to perform a
2520 	 * pseudo-lazy update with the following criteria.
2521 	 *
2522 	 * 1. Rx is given higher priority than Tx if both are in same state
2523 	 * 2. If we must reduce an ITR that is given highest priority.
2524 	 * 3. We then give priority to increasing ITR based on amount.
2525 	 */
2526 	if (q_vector->rx.target_itr < q_vector->rx.current_itr) {
2527 		/* Rx ITR needs to be reduced, this is highest priority */
2528 		intval = i40e_buildreg_itr(I40E_RX_ITR,
2529 					   q_vector->rx.target_itr);
2530 		q_vector->rx.current_itr = q_vector->rx.target_itr;
2531 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2532 	} else if ((q_vector->tx.target_itr < q_vector->tx.current_itr) ||
2533 		   ((q_vector->rx.target_itr - q_vector->rx.current_itr) <
2534 		    (q_vector->tx.target_itr - q_vector->tx.current_itr))) {
2535 		/* Tx ITR needs to be reduced, this is second priority
2536 		 * Tx ITR needs to be increased more than Rx, fourth priority
2537 		 */
2538 		intval = i40e_buildreg_itr(I40E_TX_ITR,
2539 					   q_vector->tx.target_itr);
2540 		q_vector->tx.current_itr = q_vector->tx.target_itr;
2541 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2542 	} else if (q_vector->rx.current_itr != q_vector->rx.target_itr) {
2543 		/* Rx ITR needs to be increased, third priority */
2544 		intval = i40e_buildreg_itr(I40E_RX_ITR,
2545 					   q_vector->rx.target_itr);
2546 		q_vector->rx.current_itr = q_vector->rx.target_itr;
2547 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2548 	} else {
2549 		/* No ITR update, lowest priority */
2550 		intval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
2551 		if (q_vector->itr_countdown)
2552 			q_vector->itr_countdown--;
2553 	}
2554 
2555 	if (!test_bit(__I40E_VSI_DOWN, vsi->state))
2556 		wr32(hw, INTREG(q_vector->reg_idx), intval);
2557 }
2558 
2559 /**
2560  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
2561  * @napi: napi struct with our devices info in it
2562  * @budget: amount of work driver is allowed to do this pass, in packets
2563  *
2564  * This function will clean all queues associated with a q_vector.
2565  *
2566  * Returns the amount of work done
2567  **/
2568 int i40e_napi_poll(struct napi_struct *napi, int budget)
2569 {
2570 	struct i40e_q_vector *q_vector =
2571 			       container_of(napi, struct i40e_q_vector, napi);
2572 	struct i40e_vsi *vsi = q_vector->vsi;
2573 	struct i40e_ring *ring;
2574 	bool clean_complete = true;
2575 	bool arm_wb = false;
2576 	int budget_per_ring;
2577 	int work_done = 0;
2578 
2579 	if (test_bit(__I40E_VSI_DOWN, vsi->state)) {
2580 		napi_complete(napi);
2581 		return 0;
2582 	}
2583 
2584 	/* Since the actual Tx work is minimal, we can give the Tx a larger
2585 	 * budget and be more aggressive about cleaning up the Tx descriptors.
2586 	 */
2587 	i40e_for_each_ring(ring, q_vector->tx) {
2588 		bool wd = ring->xsk_umem ?
2589 			  i40e_clean_xdp_tx_irq(vsi, ring, budget) :
2590 			  i40e_clean_tx_irq(vsi, ring, budget);
2591 
2592 		if (!wd) {
2593 			clean_complete = false;
2594 			continue;
2595 		}
2596 		arm_wb |= ring->arm_wb;
2597 		ring->arm_wb = false;
2598 	}
2599 
2600 	/* Handle case where we are called by netpoll with a budget of 0 */
2601 	if (budget <= 0)
2602 		goto tx_only;
2603 
2604 	/* We attempt to distribute budget to each Rx queue fairly, but don't
2605 	 * allow the budget to go below 1 because that would exit polling early.
2606 	 */
2607 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
2608 
2609 	i40e_for_each_ring(ring, q_vector->rx) {
2610 		int cleaned = ring->xsk_umem ?
2611 			      i40e_clean_rx_irq_zc(ring, budget_per_ring) :
2612 			      i40e_clean_rx_irq(ring, budget_per_ring);
2613 
2614 		work_done += cleaned;
2615 		/* if we clean as many as budgeted, we must not be done */
2616 		if (cleaned >= budget_per_ring)
2617 			clean_complete = false;
2618 	}
2619 
2620 	/* If work not completed, return budget and polling will return */
2621 	if (!clean_complete) {
2622 		int cpu_id = smp_processor_id();
2623 
2624 		/* It is possible that the interrupt affinity has changed but,
2625 		 * if the cpu is pegged at 100%, polling will never exit while
2626 		 * traffic continues and the interrupt will be stuck on this
2627 		 * cpu.  We check to make sure affinity is correct before we
2628 		 * continue to poll, otherwise we must stop polling so the
2629 		 * interrupt can move to the correct cpu.
2630 		 */
2631 		if (!cpumask_test_cpu(cpu_id, &q_vector->affinity_mask)) {
2632 			/* Tell napi that we are done polling */
2633 			napi_complete_done(napi, work_done);
2634 
2635 			/* Force an interrupt */
2636 			i40e_force_wb(vsi, q_vector);
2637 
2638 			/* Return budget-1 so that polling stops */
2639 			return budget - 1;
2640 		}
2641 tx_only:
2642 		if (arm_wb) {
2643 			q_vector->tx.ring[0].tx_stats.tx_force_wb++;
2644 			i40e_enable_wb_on_itr(vsi, q_vector);
2645 		}
2646 		return budget;
2647 	}
2648 
2649 	if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR)
2650 		q_vector->arm_wb_state = false;
2651 
2652 	/* Exit the polling mode, but don't re-enable interrupts if stack might
2653 	 * poll us due to busy-polling
2654 	 */
2655 	if (likely(napi_complete_done(napi, work_done)))
2656 		i40e_update_enable_itr(vsi, q_vector);
2657 
2658 	return min(work_done, budget - 1);
2659 }
2660 
2661 /**
2662  * i40e_atr - Add a Flow Director ATR filter
2663  * @tx_ring:  ring to add programming descriptor to
2664  * @skb:      send buffer
2665  * @tx_flags: send tx flags
2666  **/
2667 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
2668 		     u32 tx_flags)
2669 {
2670 	struct i40e_filter_program_desc *fdir_desc;
2671 	struct i40e_pf *pf = tx_ring->vsi->back;
2672 	union {
2673 		unsigned char *network;
2674 		struct iphdr *ipv4;
2675 		struct ipv6hdr *ipv6;
2676 	} hdr;
2677 	struct tcphdr *th;
2678 	unsigned int hlen;
2679 	u32 flex_ptype, dtype_cmd;
2680 	int l4_proto;
2681 	u16 i;
2682 
2683 	/* make sure ATR is enabled */
2684 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
2685 		return;
2686 
2687 	if (test_bit(__I40E_FD_ATR_AUTO_DISABLED, pf->state))
2688 		return;
2689 
2690 	/* if sampling is disabled do nothing */
2691 	if (!tx_ring->atr_sample_rate)
2692 		return;
2693 
2694 	/* Currently only IPv4/IPv6 with TCP is supported */
2695 	if (!(tx_flags & (I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6)))
2696 		return;
2697 
2698 	/* snag network header to get L4 type and address */
2699 	hdr.network = (tx_flags & I40E_TX_FLAGS_UDP_TUNNEL) ?
2700 		      skb_inner_network_header(skb) : skb_network_header(skb);
2701 
2702 	/* Note: tx_flags gets modified to reflect inner protocols in
2703 	 * tx_enable_csum function if encap is enabled.
2704 	 */
2705 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2706 		/* access ihl as u8 to avoid unaligned access on ia64 */
2707 		hlen = (hdr.network[0] & 0x0F) << 2;
2708 		l4_proto = hdr.ipv4->protocol;
2709 	} else {
2710 		/* find the start of the innermost ipv6 header */
2711 		unsigned int inner_hlen = hdr.network - skb->data;
2712 		unsigned int h_offset = inner_hlen;
2713 
2714 		/* this function updates h_offset to the end of the header */
2715 		l4_proto =
2716 		  ipv6_find_hdr(skb, &h_offset, IPPROTO_TCP, NULL, NULL);
2717 		/* hlen will contain our best estimate of the tcp header */
2718 		hlen = h_offset - inner_hlen;
2719 	}
2720 
2721 	if (l4_proto != IPPROTO_TCP)
2722 		return;
2723 
2724 	th = (struct tcphdr *)(hdr.network + hlen);
2725 
2726 	/* Due to lack of space, no more new filters can be programmed */
2727 	if (th->syn && test_bit(__I40E_FD_ATR_AUTO_DISABLED, pf->state))
2728 		return;
2729 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED) {
2730 		/* HW ATR eviction will take care of removing filters on FIN
2731 		 * and RST packets.
2732 		 */
2733 		if (th->fin || th->rst)
2734 			return;
2735 	}
2736 
2737 	tx_ring->atr_count++;
2738 
2739 	/* sample on all syn/fin/rst packets or once every atr sample rate */
2740 	if (!th->fin &&
2741 	    !th->syn &&
2742 	    !th->rst &&
2743 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
2744 		return;
2745 
2746 	tx_ring->atr_count = 0;
2747 
2748 	/* grab the next descriptor */
2749 	i = tx_ring->next_to_use;
2750 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
2751 
2752 	i++;
2753 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2754 
2755 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
2756 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
2757 	flex_ptype |= (tx_flags & I40E_TX_FLAGS_IPV4) ?
2758 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
2759 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
2760 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
2761 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
2762 
2763 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
2764 
2765 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
2766 
2767 	dtype_cmd |= (th->fin || th->rst) ?
2768 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
2769 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
2770 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
2771 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
2772 
2773 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
2774 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
2775 
2776 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
2777 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
2778 
2779 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
2780 	if (!(tx_flags & I40E_TX_FLAGS_UDP_TUNNEL))
2781 		dtype_cmd |=
2782 			((u32)I40E_FD_ATR_STAT_IDX(pf->hw.pf_id) <<
2783 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2784 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2785 	else
2786 		dtype_cmd |=
2787 			((u32)I40E_FD_ATR_TUNNEL_STAT_IDX(pf->hw.pf_id) <<
2788 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2789 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2790 
2791 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED)
2792 		dtype_cmd |= I40E_TXD_FLTR_QW1_ATR_MASK;
2793 
2794 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
2795 	fdir_desc->rsvd = cpu_to_le32(0);
2796 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
2797 	fdir_desc->fd_id = cpu_to_le32(0);
2798 }
2799 
2800 /**
2801  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
2802  * @skb:     send buffer
2803  * @tx_ring: ring to send buffer on
2804  * @flags:   the tx flags to be set
2805  *
2806  * Checks the skb and set up correspondingly several generic transmit flags
2807  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2808  *
2809  * Returns error code indicate the frame should be dropped upon error and the
2810  * otherwise  returns 0 to indicate the flags has been set properly.
2811  **/
2812 static inline int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2813 					     struct i40e_ring *tx_ring,
2814 					     u32 *flags)
2815 {
2816 	__be16 protocol = skb->protocol;
2817 	u32  tx_flags = 0;
2818 
2819 	if (protocol == htons(ETH_P_8021Q) &&
2820 	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
2821 		/* When HW VLAN acceleration is turned off by the user the
2822 		 * stack sets the protocol to 8021q so that the driver
2823 		 * can take any steps required to support the SW only
2824 		 * VLAN handling.  In our case the driver doesn't need
2825 		 * to take any further steps so just set the protocol
2826 		 * to the encapsulated ethertype.
2827 		 */
2828 		skb->protocol = vlan_get_protocol(skb);
2829 		goto out;
2830 	}
2831 
2832 	/* if we have a HW VLAN tag being added, default to the HW one */
2833 	if (skb_vlan_tag_present(skb)) {
2834 		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
2835 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2836 	/* else if it is a SW VLAN, check the next protocol and store the tag */
2837 	} else if (protocol == htons(ETH_P_8021Q)) {
2838 		struct vlan_hdr *vhdr, _vhdr;
2839 
2840 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
2841 		if (!vhdr)
2842 			return -EINVAL;
2843 
2844 		protocol = vhdr->h_vlan_encapsulated_proto;
2845 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
2846 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
2847 	}
2848 
2849 	if (!(tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED))
2850 		goto out;
2851 
2852 	/* Insert 802.1p priority into VLAN header */
2853 	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
2854 	    (skb->priority != TC_PRIO_CONTROL)) {
2855 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
2856 		tx_flags |= (skb->priority & 0x7) <<
2857 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
2858 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
2859 			struct vlan_ethhdr *vhdr;
2860 			int rc;
2861 
2862 			rc = skb_cow_head(skb, 0);
2863 			if (rc < 0)
2864 				return rc;
2865 			vhdr = (struct vlan_ethhdr *)skb->data;
2866 			vhdr->h_vlan_TCI = htons(tx_flags >>
2867 						 I40E_TX_FLAGS_VLAN_SHIFT);
2868 		} else {
2869 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2870 		}
2871 	}
2872 
2873 out:
2874 	*flags = tx_flags;
2875 	return 0;
2876 }
2877 
2878 /**
2879  * i40e_tso - set up the tso context descriptor
2880  * @first:    pointer to first Tx buffer for xmit
2881  * @hdr_len:  ptr to the size of the packet header
2882  * @cd_type_cmd_tso_mss: Quad Word 1
2883  *
2884  * Returns 0 if no TSO can happen, 1 if tso is going, or error
2885  **/
2886 static int i40e_tso(struct i40e_tx_buffer *first, u8 *hdr_len,
2887 		    u64 *cd_type_cmd_tso_mss)
2888 {
2889 	struct sk_buff *skb = first->skb;
2890 	u64 cd_cmd, cd_tso_len, cd_mss;
2891 	union {
2892 		struct iphdr *v4;
2893 		struct ipv6hdr *v6;
2894 		unsigned char *hdr;
2895 	} ip;
2896 	union {
2897 		struct tcphdr *tcp;
2898 		struct udphdr *udp;
2899 		unsigned char *hdr;
2900 	} l4;
2901 	u32 paylen, l4_offset;
2902 	u16 gso_segs, gso_size;
2903 	int err;
2904 
2905 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2906 		return 0;
2907 
2908 	if (!skb_is_gso(skb))
2909 		return 0;
2910 
2911 	err = skb_cow_head(skb, 0);
2912 	if (err < 0)
2913 		return err;
2914 
2915 	ip.hdr = skb_network_header(skb);
2916 	l4.hdr = skb_transport_header(skb);
2917 
2918 	/* initialize outer IP header fields */
2919 	if (ip.v4->version == 4) {
2920 		ip.v4->tot_len = 0;
2921 		ip.v4->check = 0;
2922 	} else {
2923 		ip.v6->payload_len = 0;
2924 	}
2925 
2926 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2927 					 SKB_GSO_GRE_CSUM |
2928 					 SKB_GSO_IPXIP4 |
2929 					 SKB_GSO_IPXIP6 |
2930 					 SKB_GSO_UDP_TUNNEL |
2931 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2932 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2933 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2934 			l4.udp->len = 0;
2935 
2936 			/* determine offset of outer transport header */
2937 			l4_offset = l4.hdr - skb->data;
2938 
2939 			/* remove payload length from outer checksum */
2940 			paylen = skb->len - l4_offset;
2941 			csum_replace_by_diff(&l4.udp->check,
2942 					     (__force __wsum)htonl(paylen));
2943 		}
2944 
2945 		/* reset pointers to inner headers */
2946 		ip.hdr = skb_inner_network_header(skb);
2947 		l4.hdr = skb_inner_transport_header(skb);
2948 
2949 		/* initialize inner IP header fields */
2950 		if (ip.v4->version == 4) {
2951 			ip.v4->tot_len = 0;
2952 			ip.v4->check = 0;
2953 		} else {
2954 			ip.v6->payload_len = 0;
2955 		}
2956 	}
2957 
2958 	/* determine offset of inner transport header */
2959 	l4_offset = l4.hdr - skb->data;
2960 
2961 	/* remove payload length from inner checksum */
2962 	paylen = skb->len - l4_offset;
2963 	csum_replace_by_diff(&l4.tcp->check, (__force __wsum)htonl(paylen));
2964 
2965 	/* compute length of segmentation header */
2966 	*hdr_len = (l4.tcp->doff * 4) + l4_offset;
2967 
2968 	/* pull values out of skb_shinfo */
2969 	gso_size = skb_shinfo(skb)->gso_size;
2970 	gso_segs = skb_shinfo(skb)->gso_segs;
2971 
2972 	/* update GSO size and bytecount with header size */
2973 	first->gso_segs = gso_segs;
2974 	first->bytecount += (first->gso_segs - 1) * *hdr_len;
2975 
2976 	/* find the field values */
2977 	cd_cmd = I40E_TX_CTX_DESC_TSO;
2978 	cd_tso_len = skb->len - *hdr_len;
2979 	cd_mss = gso_size;
2980 	*cd_type_cmd_tso_mss |= (cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
2981 				(cd_tso_len << I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
2982 				(cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
2983 	return 1;
2984 }
2985 
2986 /**
2987  * i40e_tsyn - set up the tsyn context descriptor
2988  * @tx_ring:  ptr to the ring to send
2989  * @skb:      ptr to the skb we're sending
2990  * @tx_flags: the collected send information
2991  * @cd_type_cmd_tso_mss: Quad Word 1
2992  *
2993  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
2994  **/
2995 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
2996 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
2997 {
2998 	struct i40e_pf *pf;
2999 
3000 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
3001 		return 0;
3002 
3003 	/* Tx timestamps cannot be sampled when doing TSO */
3004 	if (tx_flags & I40E_TX_FLAGS_TSO)
3005 		return 0;
3006 
3007 	/* only timestamp the outbound packet if the user has requested it and
3008 	 * we are not already transmitting a packet to be timestamped
3009 	 */
3010 	pf = i40e_netdev_to_pf(tx_ring->netdev);
3011 	if (!(pf->flags & I40E_FLAG_PTP))
3012 		return 0;
3013 
3014 	if (pf->ptp_tx &&
3015 	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, pf->state)) {
3016 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
3017 		pf->ptp_tx_start = jiffies;
3018 		pf->ptp_tx_skb = skb_get(skb);
3019 	} else {
3020 		pf->tx_hwtstamp_skipped++;
3021 		return 0;
3022 	}
3023 
3024 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
3025 				I40E_TXD_CTX_QW1_CMD_SHIFT;
3026 
3027 	return 1;
3028 }
3029 
3030 /**
3031  * i40e_tx_enable_csum - Enable Tx checksum offloads
3032  * @skb: send buffer
3033  * @tx_flags: pointer to Tx flags currently set
3034  * @td_cmd: Tx descriptor command bits to set
3035  * @td_offset: Tx descriptor header offsets to set
3036  * @tx_ring: Tx descriptor ring
3037  * @cd_tunneling: ptr to context desc bits
3038  **/
3039 static int i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
3040 			       u32 *td_cmd, u32 *td_offset,
3041 			       struct i40e_ring *tx_ring,
3042 			       u32 *cd_tunneling)
3043 {
3044 	union {
3045 		struct iphdr *v4;
3046 		struct ipv6hdr *v6;
3047 		unsigned char *hdr;
3048 	} ip;
3049 	union {
3050 		struct tcphdr *tcp;
3051 		struct udphdr *udp;
3052 		unsigned char *hdr;
3053 	} l4;
3054 	unsigned char *exthdr;
3055 	u32 offset, cmd = 0;
3056 	__be16 frag_off;
3057 	u8 l4_proto = 0;
3058 
3059 	if (skb->ip_summed != CHECKSUM_PARTIAL)
3060 		return 0;
3061 
3062 	ip.hdr = skb_network_header(skb);
3063 	l4.hdr = skb_transport_header(skb);
3064 
3065 	/* compute outer L2 header size */
3066 	offset = ((ip.hdr - skb->data) / 2) << I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
3067 
3068 	if (skb->encapsulation) {
3069 		u32 tunnel = 0;
3070 		/* define outer network header type */
3071 		if (*tx_flags & I40E_TX_FLAGS_IPV4) {
3072 			tunnel |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
3073 				  I40E_TX_CTX_EXT_IP_IPV4 :
3074 				  I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
3075 
3076 			l4_proto = ip.v4->protocol;
3077 		} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
3078 			tunnel |= I40E_TX_CTX_EXT_IP_IPV6;
3079 
3080 			exthdr = ip.hdr + sizeof(*ip.v6);
3081 			l4_proto = ip.v6->nexthdr;
3082 			if (l4.hdr != exthdr)
3083 				ipv6_skip_exthdr(skb, exthdr - skb->data,
3084 						 &l4_proto, &frag_off);
3085 		}
3086 
3087 		/* define outer transport */
3088 		switch (l4_proto) {
3089 		case IPPROTO_UDP:
3090 			tunnel |= I40E_TXD_CTX_UDP_TUNNELING;
3091 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
3092 			break;
3093 		case IPPROTO_GRE:
3094 			tunnel |= I40E_TXD_CTX_GRE_TUNNELING;
3095 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
3096 			break;
3097 		case IPPROTO_IPIP:
3098 		case IPPROTO_IPV6:
3099 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
3100 			l4.hdr = skb_inner_network_header(skb);
3101 			break;
3102 		default:
3103 			if (*tx_flags & I40E_TX_FLAGS_TSO)
3104 				return -1;
3105 
3106 			skb_checksum_help(skb);
3107 			return 0;
3108 		}
3109 
3110 		/* compute outer L3 header size */
3111 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
3112 			  I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT;
3113 
3114 		/* switch IP header pointer from outer to inner header */
3115 		ip.hdr = skb_inner_network_header(skb);
3116 
3117 		/* compute tunnel header size */
3118 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
3119 			  I40E_TXD_CTX_QW0_NATLEN_SHIFT;
3120 
3121 		/* indicate if we need to offload outer UDP header */
3122 		if ((*tx_flags & I40E_TX_FLAGS_TSO) &&
3123 		    !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
3124 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
3125 			tunnel |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
3126 
3127 		/* record tunnel offload values */
3128 		*cd_tunneling |= tunnel;
3129 
3130 		/* switch L4 header pointer from outer to inner */
3131 		l4.hdr = skb_inner_transport_header(skb);
3132 		l4_proto = 0;
3133 
3134 		/* reset type as we transition from outer to inner headers */
3135 		*tx_flags &= ~(I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6);
3136 		if (ip.v4->version == 4)
3137 			*tx_flags |= I40E_TX_FLAGS_IPV4;
3138 		if (ip.v6->version == 6)
3139 			*tx_flags |= I40E_TX_FLAGS_IPV6;
3140 	}
3141 
3142 	/* Enable IP checksum offloads */
3143 	if (*tx_flags & I40E_TX_FLAGS_IPV4) {
3144 		l4_proto = ip.v4->protocol;
3145 		/* the stack computes the IP header already, the only time we
3146 		 * need the hardware to recompute it is in the case of TSO.
3147 		 */
3148 		cmd |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
3149 		       I40E_TX_DESC_CMD_IIPT_IPV4_CSUM :
3150 		       I40E_TX_DESC_CMD_IIPT_IPV4;
3151 	} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
3152 		cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
3153 
3154 		exthdr = ip.hdr + sizeof(*ip.v6);
3155 		l4_proto = ip.v6->nexthdr;
3156 		if (l4.hdr != exthdr)
3157 			ipv6_skip_exthdr(skb, exthdr - skb->data,
3158 					 &l4_proto, &frag_off);
3159 	}
3160 
3161 	/* compute inner L3 header size */
3162 	offset |= ((l4.hdr - ip.hdr) / 4) << I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
3163 
3164 	/* Enable L4 checksum offloads */
3165 	switch (l4_proto) {
3166 	case IPPROTO_TCP:
3167 		/* enable checksum offloads */
3168 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
3169 		offset |= l4.tcp->doff << I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
3170 		break;
3171 	case IPPROTO_SCTP:
3172 		/* enable SCTP checksum offload */
3173 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
3174 		offset |= (sizeof(struct sctphdr) >> 2) <<
3175 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
3176 		break;
3177 	case IPPROTO_UDP:
3178 		/* enable UDP checksum offload */
3179 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
3180 		offset |= (sizeof(struct udphdr) >> 2) <<
3181 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
3182 		break;
3183 	default:
3184 		if (*tx_flags & I40E_TX_FLAGS_TSO)
3185 			return -1;
3186 		skb_checksum_help(skb);
3187 		return 0;
3188 	}
3189 
3190 	*td_cmd |= cmd;
3191 	*td_offset |= offset;
3192 
3193 	return 1;
3194 }
3195 
3196 /**
3197  * i40e_create_tx_ctx Build the Tx context descriptor
3198  * @tx_ring:  ring to create the descriptor on
3199  * @cd_type_cmd_tso_mss: Quad Word 1
3200  * @cd_tunneling: Quad Word 0 - bits 0-31
3201  * @cd_l2tag2: Quad Word 0 - bits 32-63
3202  **/
3203 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
3204 			       const u64 cd_type_cmd_tso_mss,
3205 			       const u32 cd_tunneling, const u32 cd_l2tag2)
3206 {
3207 	struct i40e_tx_context_desc *context_desc;
3208 	int i = tx_ring->next_to_use;
3209 
3210 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
3211 	    !cd_tunneling && !cd_l2tag2)
3212 		return;
3213 
3214 	/* grab the next descriptor */
3215 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
3216 
3217 	i++;
3218 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
3219 
3220 	/* cpu_to_le32 and assign to struct fields */
3221 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
3222 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
3223 	context_desc->rsvd = cpu_to_le16(0);
3224 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
3225 }
3226 
3227 /**
3228  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
3229  * @tx_ring: the ring to be checked
3230  * @size:    the size buffer we want to assure is available
3231  *
3232  * Returns -EBUSY if a stop is needed, else 0
3233  **/
3234 int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
3235 {
3236 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
3237 	/* Memory barrier before checking head and tail */
3238 	smp_mb();
3239 
3240 	/* Check again in a case another CPU has just made room available. */
3241 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
3242 		return -EBUSY;
3243 
3244 	/* A reprieve! - use start_queue because it doesn't call schedule */
3245 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
3246 	++tx_ring->tx_stats.restart_queue;
3247 	return 0;
3248 }
3249 
3250 /**
3251  * __i40e_chk_linearize - Check if there are more than 8 buffers per packet
3252  * @skb:      send buffer
3253  *
3254  * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
3255  * and so we need to figure out the cases where we need to linearize the skb.
3256  *
3257  * For TSO we need to count the TSO header and segment payload separately.
3258  * As such we need to check cases where we have 7 fragments or more as we
3259  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
3260  * the segment payload in the first descriptor, and another 7 for the
3261  * fragments.
3262  **/
3263 bool __i40e_chk_linearize(struct sk_buff *skb)
3264 {
3265 	const struct skb_frag_struct *frag, *stale;
3266 	int nr_frags, sum;
3267 
3268 	/* no need to check if number of frags is less than 7 */
3269 	nr_frags = skb_shinfo(skb)->nr_frags;
3270 	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
3271 		return false;
3272 
3273 	/* We need to walk through the list and validate that each group
3274 	 * of 6 fragments totals at least gso_size.
3275 	 */
3276 	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
3277 	frag = &skb_shinfo(skb)->frags[0];
3278 
3279 	/* Initialize size to the negative value of gso_size minus 1.  We
3280 	 * use this as the worst case scenerio in which the frag ahead
3281 	 * of us only provides one byte which is why we are limited to 6
3282 	 * descriptors for a single transmit as the header and previous
3283 	 * fragment are already consuming 2 descriptors.
3284 	 */
3285 	sum = 1 - skb_shinfo(skb)->gso_size;
3286 
3287 	/* Add size of frags 0 through 4 to create our initial sum */
3288 	sum += skb_frag_size(frag++);
3289 	sum += skb_frag_size(frag++);
3290 	sum += skb_frag_size(frag++);
3291 	sum += skb_frag_size(frag++);
3292 	sum += skb_frag_size(frag++);
3293 
3294 	/* Walk through fragments adding latest fragment, testing it, and
3295 	 * then removing stale fragments from the sum.
3296 	 */
3297 	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
3298 		int stale_size = skb_frag_size(stale);
3299 
3300 		sum += skb_frag_size(frag++);
3301 
3302 		/* The stale fragment may present us with a smaller
3303 		 * descriptor than the actual fragment size. To account
3304 		 * for that we need to remove all the data on the front and
3305 		 * figure out what the remainder would be in the last
3306 		 * descriptor associated with the fragment.
3307 		 */
3308 		if (stale_size > I40E_MAX_DATA_PER_TXD) {
3309 			int align_pad = -(stale->page_offset) &
3310 					(I40E_MAX_READ_REQ_SIZE - 1);
3311 
3312 			sum -= align_pad;
3313 			stale_size -= align_pad;
3314 
3315 			do {
3316 				sum -= I40E_MAX_DATA_PER_TXD_ALIGNED;
3317 				stale_size -= I40E_MAX_DATA_PER_TXD_ALIGNED;
3318 			} while (stale_size > I40E_MAX_DATA_PER_TXD);
3319 		}
3320 
3321 		/* if sum is negative we failed to make sufficient progress */
3322 		if (sum < 0)
3323 			return true;
3324 
3325 		if (!nr_frags--)
3326 			break;
3327 
3328 		sum -= stale_size;
3329 	}
3330 
3331 	return false;
3332 }
3333 
3334 /**
3335  * i40e_tx_map - Build the Tx descriptor
3336  * @tx_ring:  ring to send buffer on
3337  * @skb:      send buffer
3338  * @first:    first buffer info buffer to use
3339  * @tx_flags: collected send information
3340  * @hdr_len:  size of the packet header
3341  * @td_cmd:   the command field in the descriptor
3342  * @td_offset: offset for checksum or crc
3343  *
3344  * Returns 0 on success, -1 on failure to DMA
3345  **/
3346 static inline int i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
3347 			      struct i40e_tx_buffer *first, u32 tx_flags,
3348 			      const u8 hdr_len, u32 td_cmd, u32 td_offset)
3349 {
3350 	unsigned int data_len = skb->data_len;
3351 	unsigned int size = skb_headlen(skb);
3352 	struct skb_frag_struct *frag;
3353 	struct i40e_tx_buffer *tx_bi;
3354 	struct i40e_tx_desc *tx_desc;
3355 	u16 i = tx_ring->next_to_use;
3356 	u32 td_tag = 0;
3357 	dma_addr_t dma;
3358 	u16 desc_count = 1;
3359 
3360 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
3361 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
3362 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
3363 			 I40E_TX_FLAGS_VLAN_SHIFT;
3364 	}
3365 
3366 	first->tx_flags = tx_flags;
3367 
3368 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
3369 
3370 	tx_desc = I40E_TX_DESC(tx_ring, i);
3371 	tx_bi = first;
3372 
3373 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
3374 		unsigned int max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3375 
3376 		if (dma_mapping_error(tx_ring->dev, dma))
3377 			goto dma_error;
3378 
3379 		/* record length, and DMA address */
3380 		dma_unmap_len_set(tx_bi, len, size);
3381 		dma_unmap_addr_set(tx_bi, dma, dma);
3382 
3383 		/* align size to end of page */
3384 		max_data += -dma & (I40E_MAX_READ_REQ_SIZE - 1);
3385 		tx_desc->buffer_addr = cpu_to_le64(dma);
3386 
3387 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
3388 			tx_desc->cmd_type_offset_bsz =
3389 				build_ctob(td_cmd, td_offset,
3390 					   max_data, td_tag);
3391 
3392 			tx_desc++;
3393 			i++;
3394 			desc_count++;
3395 
3396 			if (i == tx_ring->count) {
3397 				tx_desc = I40E_TX_DESC(tx_ring, 0);
3398 				i = 0;
3399 			}
3400 
3401 			dma += max_data;
3402 			size -= max_data;
3403 
3404 			max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3405 			tx_desc->buffer_addr = cpu_to_le64(dma);
3406 		}
3407 
3408 		if (likely(!data_len))
3409 			break;
3410 
3411 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
3412 							  size, td_tag);
3413 
3414 		tx_desc++;
3415 		i++;
3416 		desc_count++;
3417 
3418 		if (i == tx_ring->count) {
3419 			tx_desc = I40E_TX_DESC(tx_ring, 0);
3420 			i = 0;
3421 		}
3422 
3423 		size = skb_frag_size(frag);
3424 		data_len -= size;
3425 
3426 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
3427 				       DMA_TO_DEVICE);
3428 
3429 		tx_bi = &tx_ring->tx_bi[i];
3430 	}
3431 
3432 	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
3433 
3434 	i++;
3435 	if (i == tx_ring->count)
3436 		i = 0;
3437 
3438 	tx_ring->next_to_use = i;
3439 
3440 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
3441 
3442 	/* write last descriptor with EOP bit */
3443 	td_cmd |= I40E_TX_DESC_CMD_EOP;
3444 
3445 	/* We OR these values together to check both against 4 (WB_STRIDE)
3446 	 * below. This is safe since we don't re-use desc_count afterwards.
3447 	 */
3448 	desc_count |= ++tx_ring->packet_stride;
3449 
3450 	if (desc_count >= WB_STRIDE) {
3451 		/* write last descriptor with RS bit set */
3452 		td_cmd |= I40E_TX_DESC_CMD_RS;
3453 		tx_ring->packet_stride = 0;
3454 	}
3455 
3456 	tx_desc->cmd_type_offset_bsz =
3457 			build_ctob(td_cmd, td_offset, size, td_tag);
3458 
3459 	skb_tx_timestamp(skb);
3460 
3461 	/* Force memory writes to complete before letting h/w know there
3462 	 * are new descriptors to fetch.
3463 	 *
3464 	 * We also use this memory barrier to make certain all of the
3465 	 * status bits have been updated before next_to_watch is written.
3466 	 */
3467 	wmb();
3468 
3469 	/* set next_to_watch value indicating a packet is present */
3470 	first->next_to_watch = tx_desc;
3471 
3472 	/* notify HW of packet */
3473 	if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more()) {
3474 		writel(i, tx_ring->tail);
3475 	}
3476 
3477 	return 0;
3478 
3479 dma_error:
3480 	dev_info(tx_ring->dev, "TX DMA map failed\n");
3481 
3482 	/* clear dma mappings for failed tx_bi map */
3483 	for (;;) {
3484 		tx_bi = &tx_ring->tx_bi[i];
3485 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
3486 		if (tx_bi == first)
3487 			break;
3488 		if (i == 0)
3489 			i = tx_ring->count;
3490 		i--;
3491 	}
3492 
3493 	tx_ring->next_to_use = i;
3494 
3495 	return -1;
3496 }
3497 
3498 /**
3499  * i40e_xmit_xdp_ring - transmits an XDP buffer to an XDP Tx ring
3500  * @xdp: data to transmit
3501  * @xdp_ring: XDP Tx ring
3502  **/
3503 static int i40e_xmit_xdp_ring(struct xdp_frame *xdpf,
3504 			      struct i40e_ring *xdp_ring)
3505 {
3506 	u16 i = xdp_ring->next_to_use;
3507 	struct i40e_tx_buffer *tx_bi;
3508 	struct i40e_tx_desc *tx_desc;
3509 	void *data = xdpf->data;
3510 	u32 size = xdpf->len;
3511 	dma_addr_t dma;
3512 
3513 	if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
3514 		xdp_ring->tx_stats.tx_busy++;
3515 		return I40E_XDP_CONSUMED;
3516 	}
3517 	dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
3518 	if (dma_mapping_error(xdp_ring->dev, dma))
3519 		return I40E_XDP_CONSUMED;
3520 
3521 	tx_bi = &xdp_ring->tx_bi[i];
3522 	tx_bi->bytecount = size;
3523 	tx_bi->gso_segs = 1;
3524 	tx_bi->xdpf = xdpf;
3525 
3526 	/* record length, and DMA address */
3527 	dma_unmap_len_set(tx_bi, len, size);
3528 	dma_unmap_addr_set(tx_bi, dma, dma);
3529 
3530 	tx_desc = I40E_TX_DESC(xdp_ring, i);
3531 	tx_desc->buffer_addr = cpu_to_le64(dma);
3532 	tx_desc->cmd_type_offset_bsz = build_ctob(I40E_TX_DESC_CMD_ICRC
3533 						  | I40E_TXD_CMD,
3534 						  0, size, 0);
3535 
3536 	/* Make certain all of the status bits have been updated
3537 	 * before next_to_watch is written.
3538 	 */
3539 	smp_wmb();
3540 
3541 	i++;
3542 	if (i == xdp_ring->count)
3543 		i = 0;
3544 
3545 	tx_bi->next_to_watch = tx_desc;
3546 	xdp_ring->next_to_use = i;
3547 
3548 	return I40E_XDP_TX;
3549 }
3550 
3551 /**
3552  * i40e_xmit_frame_ring - Sends buffer on Tx ring
3553  * @skb:     send buffer
3554  * @tx_ring: ring to send buffer on
3555  *
3556  * Returns NETDEV_TX_OK if sent, else an error code
3557  **/
3558 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
3559 					struct i40e_ring *tx_ring)
3560 {
3561 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
3562 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
3563 	struct i40e_tx_buffer *first;
3564 	u32 td_offset = 0;
3565 	u32 tx_flags = 0;
3566 	__be16 protocol;
3567 	u32 td_cmd = 0;
3568 	u8 hdr_len = 0;
3569 	int tso, count;
3570 	int tsyn;
3571 
3572 	/* prefetch the data, we'll need it later */
3573 	prefetch(skb->data);
3574 
3575 	i40e_trace(xmit_frame_ring, skb, tx_ring);
3576 
3577 	count = i40e_xmit_descriptor_count(skb);
3578 	if (i40e_chk_linearize(skb, count)) {
3579 		if (__skb_linearize(skb)) {
3580 			dev_kfree_skb_any(skb);
3581 			return NETDEV_TX_OK;
3582 		}
3583 		count = i40e_txd_use_count(skb->len);
3584 		tx_ring->tx_stats.tx_linearize++;
3585 	}
3586 
3587 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
3588 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
3589 	 *       + 4 desc gap to avoid the cache line where head is,
3590 	 *       + 1 desc for context descriptor,
3591 	 * otherwise try next time
3592 	 */
3593 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
3594 		tx_ring->tx_stats.tx_busy++;
3595 		return NETDEV_TX_BUSY;
3596 	}
3597 
3598 	/* record the location of the first descriptor for this packet */
3599 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
3600 	first->skb = skb;
3601 	first->bytecount = skb->len;
3602 	first->gso_segs = 1;
3603 
3604 	/* prepare the xmit flags */
3605 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
3606 		goto out_drop;
3607 
3608 	/* obtain protocol of skb */
3609 	protocol = vlan_get_protocol(skb);
3610 
3611 	/* setup IPv4/IPv6 offloads */
3612 	if (protocol == htons(ETH_P_IP))
3613 		tx_flags |= I40E_TX_FLAGS_IPV4;
3614 	else if (protocol == htons(ETH_P_IPV6))
3615 		tx_flags |= I40E_TX_FLAGS_IPV6;
3616 
3617 	tso = i40e_tso(first, &hdr_len, &cd_type_cmd_tso_mss);
3618 
3619 	if (tso < 0)
3620 		goto out_drop;
3621 	else if (tso)
3622 		tx_flags |= I40E_TX_FLAGS_TSO;
3623 
3624 	/* Always offload the checksum, since it's in the data descriptor */
3625 	tso = i40e_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset,
3626 				  tx_ring, &cd_tunneling);
3627 	if (tso < 0)
3628 		goto out_drop;
3629 
3630 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
3631 
3632 	if (tsyn)
3633 		tx_flags |= I40E_TX_FLAGS_TSYN;
3634 
3635 	/* always enable CRC insertion offload */
3636 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
3637 
3638 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
3639 			   cd_tunneling, cd_l2tag2);
3640 
3641 	/* Add Flow Director ATR if it's enabled.
3642 	 *
3643 	 * NOTE: this must always be directly before the data descriptor.
3644 	 */
3645 	i40e_atr(tx_ring, skb, tx_flags);
3646 
3647 	if (i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
3648 			td_cmd, td_offset))
3649 		goto cleanup_tx_tstamp;
3650 
3651 	return NETDEV_TX_OK;
3652 
3653 out_drop:
3654 	i40e_trace(xmit_frame_ring_drop, first->skb, tx_ring);
3655 	dev_kfree_skb_any(first->skb);
3656 	first->skb = NULL;
3657 cleanup_tx_tstamp:
3658 	if (unlikely(tx_flags & I40E_TX_FLAGS_TSYN)) {
3659 		struct i40e_pf *pf = i40e_netdev_to_pf(tx_ring->netdev);
3660 
3661 		dev_kfree_skb_any(pf->ptp_tx_skb);
3662 		pf->ptp_tx_skb = NULL;
3663 		clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, pf->state);
3664 	}
3665 
3666 	return NETDEV_TX_OK;
3667 }
3668 
3669 /**
3670  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
3671  * @skb:    send buffer
3672  * @netdev: network interface device structure
3673  *
3674  * Returns NETDEV_TX_OK if sent, else an error code
3675  **/
3676 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
3677 {
3678 	struct i40e_netdev_priv *np = netdev_priv(netdev);
3679 	struct i40e_vsi *vsi = np->vsi;
3680 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
3681 
3682 	/* hardware can't handle really short frames, hardware padding works
3683 	 * beyond this point
3684 	 */
3685 	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
3686 		return NETDEV_TX_OK;
3687 
3688 	return i40e_xmit_frame_ring(skb, tx_ring);
3689 }
3690 
3691 /**
3692  * i40e_xdp_xmit - Implements ndo_xdp_xmit
3693  * @dev: netdev
3694  * @xdp: XDP buffer
3695  *
3696  * Returns number of frames successfully sent. Frames that fail are
3697  * free'ed via XDP return API.
3698  *
3699  * For error cases, a negative errno code is returned and no-frames
3700  * are transmitted (caller must handle freeing frames).
3701  **/
3702 int i40e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
3703 		  u32 flags)
3704 {
3705 	struct i40e_netdev_priv *np = netdev_priv(dev);
3706 	unsigned int queue_index = smp_processor_id();
3707 	struct i40e_vsi *vsi = np->vsi;
3708 	struct i40e_pf *pf = vsi->back;
3709 	struct i40e_ring *xdp_ring;
3710 	int drops = 0;
3711 	int i;
3712 
3713 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
3714 		return -ENETDOWN;
3715 
3716 	if (!i40e_enabled_xdp_vsi(vsi) || queue_index >= vsi->num_queue_pairs ||
3717 	    test_bit(__I40E_CONFIG_BUSY, pf->state))
3718 		return -ENXIO;
3719 
3720 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
3721 		return -EINVAL;
3722 
3723 	xdp_ring = vsi->xdp_rings[queue_index];
3724 
3725 	for (i = 0; i < n; i++) {
3726 		struct xdp_frame *xdpf = frames[i];
3727 		int err;
3728 
3729 		err = i40e_xmit_xdp_ring(xdpf, xdp_ring);
3730 		if (err != I40E_XDP_TX) {
3731 			xdp_return_frame_rx_napi(xdpf);
3732 			drops++;
3733 		}
3734 	}
3735 
3736 	if (unlikely(flags & XDP_XMIT_FLUSH))
3737 		i40e_xdp_ring_update_tail(xdp_ring);
3738 
3739 	return n - drops;
3740 }
3741