1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 - 2016 Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program.  If not, see <http://www.gnu.org/licenses/>.
17  *
18  * The full GNU General Public License is included in this distribution in
19  * the file called "COPYING".
20  *
21  * Contact Information:
22  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  ******************************************************************************/
26 
27 #include <linux/prefetch.h>
28 #include <net/busy_poll.h>
29 #include "i40e.h"
30 #include "i40e_trace.h"
31 #include "i40e_prototype.h"
32 
33 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
34 				u32 td_tag)
35 {
36 	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
37 			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
38 			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
39 			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
40 			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
41 }
42 
43 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
44 /**
45  * i40e_fdir - Generate a Flow Director descriptor based on fdata
46  * @tx_ring: Tx ring to send buffer on
47  * @fdata: Flow director filter data
48  * @add: Indicate if we are adding a rule or deleting one
49  *
50  **/
51 static void i40e_fdir(struct i40e_ring *tx_ring,
52 		      struct i40e_fdir_filter *fdata, bool add)
53 {
54 	struct i40e_filter_program_desc *fdir_desc;
55 	struct i40e_pf *pf = tx_ring->vsi->back;
56 	u32 flex_ptype, dtype_cmd;
57 	u16 i;
58 
59 	/* grab the next descriptor */
60 	i = tx_ring->next_to_use;
61 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
62 
63 	i++;
64 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
65 
66 	flex_ptype = I40E_TXD_FLTR_QW0_QINDEX_MASK &
67 		     (fdata->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT);
68 
69 	flex_ptype |= I40E_TXD_FLTR_QW0_FLEXOFF_MASK &
70 		      (fdata->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
71 
72 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
73 		      (fdata->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
74 
75 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
76 		      (fdata->flex_offset << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
77 
78 	/* Use LAN VSI Id if not programmed by user */
79 	flex_ptype |= I40E_TXD_FLTR_QW0_DEST_VSI_MASK &
80 		      ((u32)(fdata->dest_vsi ? : pf->vsi[pf->lan_vsi]->id) <<
81 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT);
82 
83 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
84 
85 	dtype_cmd |= add ?
86 		     I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
87 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT :
88 		     I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
89 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT;
90 
91 	dtype_cmd |= I40E_TXD_FLTR_QW1_DEST_MASK &
92 		     (fdata->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT);
93 
94 	dtype_cmd |= I40E_TXD_FLTR_QW1_FD_STATUS_MASK &
95 		     (fdata->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT);
96 
97 	if (fdata->cnt_index) {
98 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
99 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNTINDEX_MASK &
100 			     ((u32)fdata->cnt_index <<
101 			      I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT);
102 	}
103 
104 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
105 	fdir_desc->rsvd = cpu_to_le32(0);
106 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
107 	fdir_desc->fd_id = cpu_to_le32(fdata->fd_id);
108 }
109 
110 #define I40E_FD_CLEAN_DELAY 10
111 /**
112  * i40e_program_fdir_filter - Program a Flow Director filter
113  * @fdir_data: Packet data that will be filter parameters
114  * @raw_packet: the pre-allocated packet buffer for FDir
115  * @pf: The PF pointer
116  * @add: True for add/update, False for remove
117  **/
118 static int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data,
119 				    u8 *raw_packet, struct i40e_pf *pf,
120 				    bool add)
121 {
122 	struct i40e_tx_buffer *tx_buf, *first;
123 	struct i40e_tx_desc *tx_desc;
124 	struct i40e_ring *tx_ring;
125 	struct i40e_vsi *vsi;
126 	struct device *dev;
127 	dma_addr_t dma;
128 	u32 td_cmd = 0;
129 	u16 i;
130 
131 	/* find existing FDIR VSI */
132 	vsi = i40e_find_vsi_by_type(pf, I40E_VSI_FDIR);
133 	if (!vsi)
134 		return -ENOENT;
135 
136 	tx_ring = vsi->tx_rings[0];
137 	dev = tx_ring->dev;
138 
139 	/* we need two descriptors to add/del a filter and we can wait */
140 	for (i = I40E_FD_CLEAN_DELAY; I40E_DESC_UNUSED(tx_ring) < 2; i--) {
141 		if (!i)
142 			return -EAGAIN;
143 		msleep_interruptible(1);
144 	}
145 
146 	dma = dma_map_single(dev, raw_packet,
147 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
148 	if (dma_mapping_error(dev, dma))
149 		goto dma_fail;
150 
151 	/* grab the next descriptor */
152 	i = tx_ring->next_to_use;
153 	first = &tx_ring->tx_bi[i];
154 	i40e_fdir(tx_ring, fdir_data, add);
155 
156 	/* Now program a dummy descriptor */
157 	i = tx_ring->next_to_use;
158 	tx_desc = I40E_TX_DESC(tx_ring, i);
159 	tx_buf = &tx_ring->tx_bi[i];
160 
161 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
162 
163 	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
164 
165 	/* record length, and DMA address */
166 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
167 	dma_unmap_addr_set(tx_buf, dma, dma);
168 
169 	tx_desc->buffer_addr = cpu_to_le64(dma);
170 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
171 
172 	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
173 	tx_buf->raw_buf = (void *)raw_packet;
174 
175 	tx_desc->cmd_type_offset_bsz =
176 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
177 
178 	/* Force memory writes to complete before letting h/w
179 	 * know there are new descriptors to fetch.
180 	 */
181 	wmb();
182 
183 	/* Mark the data descriptor to be watched */
184 	first->next_to_watch = tx_desc;
185 
186 	writel(tx_ring->next_to_use, tx_ring->tail);
187 	return 0;
188 
189 dma_fail:
190 	return -1;
191 }
192 
193 #define IP_HEADER_OFFSET 14
194 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
195 /**
196  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
197  * @vsi: pointer to the targeted VSI
198  * @fd_data: the flow director data required for the FDir descriptor
199  * @add: true adds a filter, false removes it
200  *
201  * Returns 0 if the filters were successfully added or removed
202  **/
203 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
204 				   struct i40e_fdir_filter *fd_data,
205 				   bool add)
206 {
207 	struct i40e_pf *pf = vsi->back;
208 	struct udphdr *udp;
209 	struct iphdr *ip;
210 	u8 *raw_packet;
211 	int ret;
212 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
213 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
214 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
215 
216 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
217 	if (!raw_packet)
218 		return -ENOMEM;
219 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
220 
221 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
222 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
223 	      + sizeof(struct iphdr));
224 
225 	ip->daddr = fd_data->dst_ip;
226 	udp->dest = fd_data->dst_port;
227 	ip->saddr = fd_data->src_ip;
228 	udp->source = fd_data->src_port;
229 
230 	if (fd_data->flex_filter) {
231 		u8 *payload = raw_packet + I40E_UDPIP_DUMMY_PACKET_LEN;
232 		__be16 pattern = fd_data->flex_word;
233 		u16 off = fd_data->flex_offset;
234 
235 		*((__force __be16 *)(payload + off)) = pattern;
236 	}
237 
238 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
239 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
240 	if (ret) {
241 		dev_info(&pf->pdev->dev,
242 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
243 			 fd_data->pctype, fd_data->fd_id, ret);
244 		/* Free the packet buffer since it wasn't added to the ring */
245 		kfree(raw_packet);
246 		return -EOPNOTSUPP;
247 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
248 		if (add)
249 			dev_info(&pf->pdev->dev,
250 				 "Filter OK for PCTYPE %d loc = %d\n",
251 				 fd_data->pctype, fd_data->fd_id);
252 		else
253 			dev_info(&pf->pdev->dev,
254 				 "Filter deleted for PCTYPE %d loc = %d\n",
255 				 fd_data->pctype, fd_data->fd_id);
256 	}
257 
258 	if (add)
259 		pf->fd_udp4_filter_cnt++;
260 	else
261 		pf->fd_udp4_filter_cnt--;
262 
263 	return 0;
264 }
265 
266 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
267 /**
268  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
269  * @vsi: pointer to the targeted VSI
270  * @fd_data: the flow director data required for the FDir descriptor
271  * @add: true adds a filter, false removes it
272  *
273  * Returns 0 if the filters were successfully added or removed
274  **/
275 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
276 				   struct i40e_fdir_filter *fd_data,
277 				   bool add)
278 {
279 	struct i40e_pf *pf = vsi->back;
280 	struct tcphdr *tcp;
281 	struct iphdr *ip;
282 	u8 *raw_packet;
283 	int ret;
284 	/* Dummy packet */
285 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
286 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
287 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
288 		0x0, 0x72, 0, 0, 0, 0};
289 
290 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
291 	if (!raw_packet)
292 		return -ENOMEM;
293 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
294 
295 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
296 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
297 	      + sizeof(struct iphdr));
298 
299 	ip->daddr = fd_data->dst_ip;
300 	tcp->dest = fd_data->dst_port;
301 	ip->saddr = fd_data->src_ip;
302 	tcp->source = fd_data->src_port;
303 
304 	if (fd_data->flex_filter) {
305 		u8 *payload = raw_packet + I40E_TCPIP_DUMMY_PACKET_LEN;
306 		__be16 pattern = fd_data->flex_word;
307 		u16 off = fd_data->flex_offset;
308 
309 		*((__force __be16 *)(payload + off)) = pattern;
310 	}
311 
312 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
313 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
314 	if (ret) {
315 		dev_info(&pf->pdev->dev,
316 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
317 			 fd_data->pctype, fd_data->fd_id, ret);
318 		/* Free the packet buffer since it wasn't added to the ring */
319 		kfree(raw_packet);
320 		return -EOPNOTSUPP;
321 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
322 		if (add)
323 			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
324 				 fd_data->pctype, fd_data->fd_id);
325 		else
326 			dev_info(&pf->pdev->dev,
327 				 "Filter deleted for PCTYPE %d loc = %d\n",
328 				 fd_data->pctype, fd_data->fd_id);
329 	}
330 
331 	if (add) {
332 		pf->fd_tcp4_filter_cnt++;
333 		if ((pf->flags & I40E_FLAG_FD_ATR_ENABLED) &&
334 		    I40E_DEBUG_FD & pf->hw.debug_mask)
335 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
336 		pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
337 	} else {
338 		pf->fd_tcp4_filter_cnt--;
339 	}
340 
341 	return 0;
342 }
343 
344 #define I40E_SCTPIP_DUMMY_PACKET_LEN 46
345 /**
346  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
347  * a specific flow spec
348  * @vsi: pointer to the targeted VSI
349  * @fd_data: the flow director data required for the FDir descriptor
350  * @add: true adds a filter, false removes it
351  *
352  * Returns 0 if the filters were successfully added or removed
353  **/
354 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
355 				    struct i40e_fdir_filter *fd_data,
356 				    bool add)
357 {
358 	struct i40e_pf *pf = vsi->back;
359 	struct sctphdr *sctp;
360 	struct iphdr *ip;
361 	u8 *raw_packet;
362 	int ret;
363 	/* Dummy packet */
364 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
365 		0x45, 0, 0, 0x20, 0, 0, 0x40, 0, 0x40, 0x84, 0, 0, 0, 0, 0, 0,
366 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
367 
368 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
369 	if (!raw_packet)
370 		return -ENOMEM;
371 	memcpy(raw_packet, packet, I40E_SCTPIP_DUMMY_PACKET_LEN);
372 
373 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
374 	sctp = (struct sctphdr *)(raw_packet + IP_HEADER_OFFSET
375 	      + sizeof(struct iphdr));
376 
377 	ip->daddr = fd_data->dst_ip;
378 	sctp->dest = fd_data->dst_port;
379 	ip->saddr = fd_data->src_ip;
380 	sctp->source = fd_data->src_port;
381 
382 	if (fd_data->flex_filter) {
383 		u8 *payload = raw_packet + I40E_SCTPIP_DUMMY_PACKET_LEN;
384 		__be16 pattern = fd_data->flex_word;
385 		u16 off = fd_data->flex_offset;
386 
387 		*((__force __be16 *)(payload + off)) = pattern;
388 	}
389 
390 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_SCTP;
391 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
392 	if (ret) {
393 		dev_info(&pf->pdev->dev,
394 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
395 			 fd_data->pctype, fd_data->fd_id, ret);
396 		/* Free the packet buffer since it wasn't added to the ring */
397 		kfree(raw_packet);
398 		return -EOPNOTSUPP;
399 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
400 		if (add)
401 			dev_info(&pf->pdev->dev,
402 				 "Filter OK for PCTYPE %d loc = %d\n",
403 				 fd_data->pctype, fd_data->fd_id);
404 		else
405 			dev_info(&pf->pdev->dev,
406 				 "Filter deleted for PCTYPE %d loc = %d\n",
407 				 fd_data->pctype, fd_data->fd_id);
408 	}
409 
410 	if (add)
411 		pf->fd_sctp4_filter_cnt++;
412 	else
413 		pf->fd_sctp4_filter_cnt--;
414 
415 	return 0;
416 }
417 
418 #define I40E_IP_DUMMY_PACKET_LEN 34
419 /**
420  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
421  * a specific flow spec
422  * @vsi: pointer to the targeted VSI
423  * @fd_data: the flow director data required for the FDir descriptor
424  * @add: true adds a filter, false removes it
425  *
426  * Returns 0 if the filters were successfully added or removed
427  **/
428 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
429 				  struct i40e_fdir_filter *fd_data,
430 				  bool add)
431 {
432 	struct i40e_pf *pf = vsi->back;
433 	struct iphdr *ip;
434 	u8 *raw_packet;
435 	int ret;
436 	int i;
437 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
438 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
439 		0, 0, 0, 0};
440 
441 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
442 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
443 		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
444 		if (!raw_packet)
445 			return -ENOMEM;
446 		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
447 		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
448 
449 		ip->saddr = fd_data->src_ip;
450 		ip->daddr = fd_data->dst_ip;
451 		ip->protocol = 0;
452 
453 		if (fd_data->flex_filter) {
454 			u8 *payload = raw_packet + I40E_IP_DUMMY_PACKET_LEN;
455 			__be16 pattern = fd_data->flex_word;
456 			u16 off = fd_data->flex_offset;
457 
458 			*((__force __be16 *)(payload + off)) = pattern;
459 		}
460 
461 		fd_data->pctype = i;
462 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
463 		if (ret) {
464 			dev_info(&pf->pdev->dev,
465 				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
466 				 fd_data->pctype, fd_data->fd_id, ret);
467 			/* The packet buffer wasn't added to the ring so we
468 			 * need to free it now.
469 			 */
470 			kfree(raw_packet);
471 			return -EOPNOTSUPP;
472 		} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
473 			if (add)
474 				dev_info(&pf->pdev->dev,
475 					 "Filter OK for PCTYPE %d loc = %d\n",
476 					 fd_data->pctype, fd_data->fd_id);
477 			else
478 				dev_info(&pf->pdev->dev,
479 					 "Filter deleted for PCTYPE %d loc = %d\n",
480 					 fd_data->pctype, fd_data->fd_id);
481 		}
482 	}
483 
484 	if (add)
485 		pf->fd_ip4_filter_cnt++;
486 	else
487 		pf->fd_ip4_filter_cnt--;
488 
489 	return 0;
490 }
491 
492 /**
493  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
494  * @vsi: pointer to the targeted VSI
495  * @cmd: command to get or set RX flow classification rules
496  * @add: true adds a filter, false removes it
497  *
498  **/
499 int i40e_add_del_fdir(struct i40e_vsi *vsi,
500 		      struct i40e_fdir_filter *input, bool add)
501 {
502 	struct i40e_pf *pf = vsi->back;
503 	int ret;
504 
505 	switch (input->flow_type & ~FLOW_EXT) {
506 	case TCP_V4_FLOW:
507 		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
508 		break;
509 	case UDP_V4_FLOW:
510 		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
511 		break;
512 	case SCTP_V4_FLOW:
513 		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
514 		break;
515 	case IP_USER_FLOW:
516 		switch (input->ip4_proto) {
517 		case IPPROTO_TCP:
518 			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
519 			break;
520 		case IPPROTO_UDP:
521 			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
522 			break;
523 		case IPPROTO_SCTP:
524 			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
525 			break;
526 		case IPPROTO_IP:
527 			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
528 			break;
529 		default:
530 			/* We cannot support masking based on protocol */
531 			dev_info(&pf->pdev->dev, "Unsupported IPv4 protocol 0x%02x\n",
532 				 input->ip4_proto);
533 			return -EINVAL;
534 		}
535 		break;
536 	default:
537 		dev_info(&pf->pdev->dev, "Unsupported flow type 0x%02x\n",
538 			 input->flow_type);
539 		return -EINVAL;
540 	}
541 
542 	/* The buffer allocated here will be normally be freed by
543 	 * i40e_clean_fdir_tx_irq() as it reclaims resources after transmit
544 	 * completion. In the event of an error adding the buffer to the FDIR
545 	 * ring, it will immediately be freed. It may also be freed by
546 	 * i40e_clean_tx_ring() when closing the VSI.
547 	 */
548 	return ret;
549 }
550 
551 /**
552  * i40e_fd_handle_status - check the Programming Status for FD
553  * @rx_ring: the Rx ring for this descriptor
554  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
555  * @prog_id: the id originally used for programming
556  *
557  * This is used to verify if the FD programming or invalidation
558  * requested by SW to the HW is successful or not and take actions accordingly.
559  **/
560 static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
561 				  union i40e_rx_desc *rx_desc, u8 prog_id)
562 {
563 	struct i40e_pf *pf = rx_ring->vsi->back;
564 	struct pci_dev *pdev = pf->pdev;
565 	u32 fcnt_prog, fcnt_avail;
566 	u32 error;
567 	u64 qw;
568 
569 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
570 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
571 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
572 
573 	if (error == BIT(I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
574 		pf->fd_inv = le32_to_cpu(rx_desc->wb.qword0.hi_dword.fd_id);
575 		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
576 		    (I40E_DEBUG_FD & pf->hw.debug_mask))
577 			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
578 				 pf->fd_inv);
579 
580 		/* Check if the programming error is for ATR.
581 		 * If so, auto disable ATR and set a state for
582 		 * flush in progress. Next time we come here if flush is in
583 		 * progress do nothing, once flush is complete the state will
584 		 * be cleared.
585 		 */
586 		if (test_bit(__I40E_FD_FLUSH_REQUESTED, pf->state))
587 			return;
588 
589 		pf->fd_add_err++;
590 		/* store the current atr filter count */
591 		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
592 
593 		if ((rx_desc->wb.qword0.hi_dword.fd_id == 0) &&
594 		    pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED) {
595 			pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
596 			set_bit(__I40E_FD_FLUSH_REQUESTED, pf->state);
597 		}
598 
599 		/* filter programming failed most likely due to table full */
600 		fcnt_prog = i40e_get_global_fd_count(pf);
601 		fcnt_avail = pf->fdir_pf_filter_count;
602 		/* If ATR is running fcnt_prog can quickly change,
603 		 * if we are very close to full, it makes sense to disable
604 		 * FD ATR/SB and then re-enable it when there is room.
605 		 */
606 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
607 			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
608 			    !(pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED)) {
609 				pf->flags |= I40E_FLAG_FD_SB_AUTO_DISABLED;
610 				if (I40E_DEBUG_FD & pf->hw.debug_mask)
611 					dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
612 			}
613 		}
614 	} else if (error == BIT(I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
615 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
616 			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
617 				 rx_desc->wb.qword0.hi_dword.fd_id);
618 	}
619 }
620 
621 /**
622  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
623  * @ring:      the ring that owns the buffer
624  * @tx_buffer: the buffer to free
625  **/
626 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
627 					    struct i40e_tx_buffer *tx_buffer)
628 {
629 	if (tx_buffer->skb) {
630 		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
631 			kfree(tx_buffer->raw_buf);
632 		else
633 			dev_kfree_skb_any(tx_buffer->skb);
634 		if (dma_unmap_len(tx_buffer, len))
635 			dma_unmap_single(ring->dev,
636 					 dma_unmap_addr(tx_buffer, dma),
637 					 dma_unmap_len(tx_buffer, len),
638 					 DMA_TO_DEVICE);
639 	} else if (dma_unmap_len(tx_buffer, len)) {
640 		dma_unmap_page(ring->dev,
641 			       dma_unmap_addr(tx_buffer, dma),
642 			       dma_unmap_len(tx_buffer, len),
643 			       DMA_TO_DEVICE);
644 	}
645 
646 	tx_buffer->next_to_watch = NULL;
647 	tx_buffer->skb = NULL;
648 	dma_unmap_len_set(tx_buffer, len, 0);
649 	/* tx_buffer must be completely set up in the transmit path */
650 }
651 
652 /**
653  * i40e_clean_tx_ring - Free any empty Tx buffers
654  * @tx_ring: ring to be cleaned
655  **/
656 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
657 {
658 	unsigned long bi_size;
659 	u16 i;
660 
661 	/* ring already cleared, nothing to do */
662 	if (!tx_ring->tx_bi)
663 		return;
664 
665 	/* Free all the Tx ring sk_buffs */
666 	for (i = 0; i < tx_ring->count; i++)
667 		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
668 
669 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
670 	memset(tx_ring->tx_bi, 0, bi_size);
671 
672 	/* Zero out the descriptor ring */
673 	memset(tx_ring->desc, 0, tx_ring->size);
674 
675 	tx_ring->next_to_use = 0;
676 	tx_ring->next_to_clean = 0;
677 
678 	if (!tx_ring->netdev)
679 		return;
680 
681 	/* cleanup Tx queue statistics */
682 	netdev_tx_reset_queue(txring_txq(tx_ring));
683 }
684 
685 /**
686  * i40e_free_tx_resources - Free Tx resources per queue
687  * @tx_ring: Tx descriptor ring for a specific queue
688  *
689  * Free all transmit software resources
690  **/
691 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
692 {
693 	i40e_clean_tx_ring(tx_ring);
694 	kfree(tx_ring->tx_bi);
695 	tx_ring->tx_bi = NULL;
696 
697 	if (tx_ring->desc) {
698 		dma_free_coherent(tx_ring->dev, tx_ring->size,
699 				  tx_ring->desc, tx_ring->dma);
700 		tx_ring->desc = NULL;
701 	}
702 }
703 
704 /**
705  * i40e_get_tx_pending - how many tx descriptors not processed
706  * @tx_ring: the ring of descriptors
707  *
708  * Since there is no access to the ring head register
709  * in XL710, we need to use our local copies
710  **/
711 u32 i40e_get_tx_pending(struct i40e_ring *ring)
712 {
713 	u32 head, tail;
714 
715 	head = i40e_get_head(ring);
716 	tail = readl(ring->tail);
717 
718 	if (head != tail)
719 		return (head < tail) ?
720 			tail - head : (tail + ring->count - head);
721 
722 	return 0;
723 }
724 
725 #define WB_STRIDE 4
726 
727 /**
728  * i40e_clean_tx_irq - Reclaim resources after transmit completes
729  * @vsi: the VSI we care about
730  * @tx_ring: Tx ring to clean
731  * @napi_budget: Used to determine if we are in netpoll
732  *
733  * Returns true if there's any budget left (e.g. the clean is finished)
734  **/
735 static bool i40e_clean_tx_irq(struct i40e_vsi *vsi,
736 			      struct i40e_ring *tx_ring, int napi_budget)
737 {
738 	u16 i = tx_ring->next_to_clean;
739 	struct i40e_tx_buffer *tx_buf;
740 	struct i40e_tx_desc *tx_head;
741 	struct i40e_tx_desc *tx_desc;
742 	unsigned int total_bytes = 0, total_packets = 0;
743 	unsigned int budget = vsi->work_limit;
744 
745 	tx_buf = &tx_ring->tx_bi[i];
746 	tx_desc = I40E_TX_DESC(tx_ring, i);
747 	i -= tx_ring->count;
748 
749 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
750 
751 	do {
752 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
753 
754 		/* if next_to_watch is not set then there is no work pending */
755 		if (!eop_desc)
756 			break;
757 
758 		/* prevent any other reads prior to eop_desc */
759 		read_barrier_depends();
760 
761 		i40e_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
762 		/* we have caught up to head, no work left to do */
763 		if (tx_head == tx_desc)
764 			break;
765 
766 		/* clear next_to_watch to prevent false hangs */
767 		tx_buf->next_to_watch = NULL;
768 
769 		/* update the statistics for this packet */
770 		total_bytes += tx_buf->bytecount;
771 		total_packets += tx_buf->gso_segs;
772 
773 		/* free the skb */
774 		napi_consume_skb(tx_buf->skb, napi_budget);
775 
776 		/* unmap skb header data */
777 		dma_unmap_single(tx_ring->dev,
778 				 dma_unmap_addr(tx_buf, dma),
779 				 dma_unmap_len(tx_buf, len),
780 				 DMA_TO_DEVICE);
781 
782 		/* clear tx_buffer data */
783 		tx_buf->skb = NULL;
784 		dma_unmap_len_set(tx_buf, len, 0);
785 
786 		/* unmap remaining buffers */
787 		while (tx_desc != eop_desc) {
788 			i40e_trace(clean_tx_irq_unmap,
789 				   tx_ring, tx_desc, tx_buf);
790 
791 			tx_buf++;
792 			tx_desc++;
793 			i++;
794 			if (unlikely(!i)) {
795 				i -= tx_ring->count;
796 				tx_buf = tx_ring->tx_bi;
797 				tx_desc = I40E_TX_DESC(tx_ring, 0);
798 			}
799 
800 			/* unmap any remaining paged data */
801 			if (dma_unmap_len(tx_buf, len)) {
802 				dma_unmap_page(tx_ring->dev,
803 					       dma_unmap_addr(tx_buf, dma),
804 					       dma_unmap_len(tx_buf, len),
805 					       DMA_TO_DEVICE);
806 				dma_unmap_len_set(tx_buf, len, 0);
807 			}
808 		}
809 
810 		/* move us one more past the eop_desc for start of next pkt */
811 		tx_buf++;
812 		tx_desc++;
813 		i++;
814 		if (unlikely(!i)) {
815 			i -= tx_ring->count;
816 			tx_buf = tx_ring->tx_bi;
817 			tx_desc = I40E_TX_DESC(tx_ring, 0);
818 		}
819 
820 		prefetch(tx_desc);
821 
822 		/* update budget accounting */
823 		budget--;
824 	} while (likely(budget));
825 
826 	i += tx_ring->count;
827 	tx_ring->next_to_clean = i;
828 	u64_stats_update_begin(&tx_ring->syncp);
829 	tx_ring->stats.bytes += total_bytes;
830 	tx_ring->stats.packets += total_packets;
831 	u64_stats_update_end(&tx_ring->syncp);
832 	tx_ring->q_vector->tx.total_bytes += total_bytes;
833 	tx_ring->q_vector->tx.total_packets += total_packets;
834 
835 	if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
836 		/* check to see if there are < 4 descriptors
837 		 * waiting to be written back, then kick the hardware to force
838 		 * them to be written back in case we stay in NAPI.
839 		 * In this mode on X722 we do not enable Interrupt.
840 		 */
841 		unsigned int j = i40e_get_tx_pending(tx_ring);
842 
843 		if (budget &&
844 		    ((j / WB_STRIDE) == 0) && (j > 0) &&
845 		    !test_bit(__I40E_VSI_DOWN, vsi->state) &&
846 		    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
847 			tx_ring->arm_wb = true;
848 	}
849 
850 	/* notify netdev of completed buffers */
851 	netdev_tx_completed_queue(txring_txq(tx_ring),
852 				  total_packets, total_bytes);
853 
854 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
855 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
856 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
857 		/* Make sure that anybody stopping the queue after this
858 		 * sees the new next_to_clean.
859 		 */
860 		smp_mb();
861 		if (__netif_subqueue_stopped(tx_ring->netdev,
862 					     tx_ring->queue_index) &&
863 		   !test_bit(__I40E_VSI_DOWN, vsi->state)) {
864 			netif_wake_subqueue(tx_ring->netdev,
865 					    tx_ring->queue_index);
866 			++tx_ring->tx_stats.restart_queue;
867 		}
868 	}
869 
870 	return !!budget;
871 }
872 
873 /**
874  * i40e_enable_wb_on_itr - Arm hardware to do a wb, interrupts are not enabled
875  * @vsi: the VSI we care about
876  * @q_vector: the vector on which to enable writeback
877  *
878  **/
879 static void i40e_enable_wb_on_itr(struct i40e_vsi *vsi,
880 				  struct i40e_q_vector *q_vector)
881 {
882 	u16 flags = q_vector->tx.ring[0].flags;
883 	u32 val;
884 
885 	if (!(flags & I40E_TXR_FLAGS_WB_ON_ITR))
886 		return;
887 
888 	if (q_vector->arm_wb_state)
889 		return;
890 
891 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
892 		val = I40E_PFINT_DYN_CTLN_WB_ON_ITR_MASK |
893 		      I40E_PFINT_DYN_CTLN_ITR_INDX_MASK; /* set noitr */
894 
895 		wr32(&vsi->back->hw,
896 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx + vsi->base_vector - 1),
897 		     val);
898 	} else {
899 		val = I40E_PFINT_DYN_CTL0_WB_ON_ITR_MASK |
900 		      I40E_PFINT_DYN_CTL0_ITR_INDX_MASK; /* set noitr */
901 
902 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
903 	}
904 	q_vector->arm_wb_state = true;
905 }
906 
907 /**
908  * i40e_force_wb - Issue SW Interrupt so HW does a wb
909  * @vsi: the VSI we care about
910  * @q_vector: the vector  on which to force writeback
911  *
912  **/
913 void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
914 {
915 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
916 		u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
917 			  I40E_PFINT_DYN_CTLN_ITR_INDX_MASK | /* set noitr */
918 			  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
919 			  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
920 			  /* allow 00 to be written to the index */
921 
922 		wr32(&vsi->back->hw,
923 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx +
924 					 vsi->base_vector - 1), val);
925 	} else {
926 		u32 val = I40E_PFINT_DYN_CTL0_INTENA_MASK |
927 			  I40E_PFINT_DYN_CTL0_ITR_INDX_MASK | /* set noitr */
928 			  I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK |
929 			  I40E_PFINT_DYN_CTL0_SW_ITR_INDX_ENA_MASK;
930 			/* allow 00 to be written to the index */
931 
932 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
933 	}
934 }
935 
936 /**
937  * i40e_set_new_dynamic_itr - Find new ITR level
938  * @rc: structure containing ring performance data
939  *
940  * Returns true if ITR changed, false if not
941  *
942  * Stores a new ITR value based on packets and byte counts during
943  * the last interrupt.  The advantage of per interrupt computation
944  * is faster updates and more accurate ITR for the current traffic
945  * pattern.  Constants in this function were computed based on
946  * theoretical maximum wire speed and thresholds were set based on
947  * testing data as well as attempting to minimize response time
948  * while increasing bulk throughput.
949  **/
950 static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
951 {
952 	enum i40e_latency_range new_latency_range = rc->latency_range;
953 	struct i40e_q_vector *qv = rc->ring->q_vector;
954 	u32 new_itr = rc->itr;
955 	int bytes_per_int;
956 	int usecs;
957 
958 	if (rc->total_packets == 0 || !rc->itr)
959 		return false;
960 
961 	/* simple throttlerate management
962 	 *   0-10MB/s   lowest (50000 ints/s)
963 	 *  10-20MB/s   low    (20000 ints/s)
964 	 *  20-1249MB/s bulk   (18000 ints/s)
965 	 *  > 40000 Rx packets per second (8000 ints/s)
966 	 *
967 	 * The math works out because the divisor is in 10^(-6) which
968 	 * turns the bytes/us input value into MB/s values, but
969 	 * make sure to use usecs, as the register values written
970 	 * are in 2 usec increments in the ITR registers, and make sure
971 	 * to use the smoothed values that the countdown timer gives us.
972 	 */
973 	usecs = (rc->itr << 1) * ITR_COUNTDOWN_START;
974 	bytes_per_int = rc->total_bytes / usecs;
975 
976 	switch (new_latency_range) {
977 	case I40E_LOWEST_LATENCY:
978 		if (bytes_per_int > 10)
979 			new_latency_range = I40E_LOW_LATENCY;
980 		break;
981 	case I40E_LOW_LATENCY:
982 		if (bytes_per_int > 20)
983 			new_latency_range = I40E_BULK_LATENCY;
984 		else if (bytes_per_int <= 10)
985 			new_latency_range = I40E_LOWEST_LATENCY;
986 		break;
987 	case I40E_BULK_LATENCY:
988 	case I40E_ULTRA_LATENCY:
989 	default:
990 		if (bytes_per_int <= 20)
991 			new_latency_range = I40E_LOW_LATENCY;
992 		break;
993 	}
994 
995 	/* this is to adjust RX more aggressively when streaming small
996 	 * packets.  The value of 40000 was picked as it is just beyond
997 	 * what the hardware can receive per second if in low latency
998 	 * mode.
999 	 */
1000 #define RX_ULTRA_PACKET_RATE 40000
1001 
1002 	if ((((rc->total_packets * 1000000) / usecs) > RX_ULTRA_PACKET_RATE) &&
1003 	    (&qv->rx == rc))
1004 		new_latency_range = I40E_ULTRA_LATENCY;
1005 
1006 	rc->latency_range = new_latency_range;
1007 
1008 	switch (new_latency_range) {
1009 	case I40E_LOWEST_LATENCY:
1010 		new_itr = I40E_ITR_50K;
1011 		break;
1012 	case I40E_LOW_LATENCY:
1013 		new_itr = I40E_ITR_20K;
1014 		break;
1015 	case I40E_BULK_LATENCY:
1016 		new_itr = I40E_ITR_18K;
1017 		break;
1018 	case I40E_ULTRA_LATENCY:
1019 		new_itr = I40E_ITR_8K;
1020 		break;
1021 	default:
1022 		break;
1023 	}
1024 
1025 	rc->total_bytes = 0;
1026 	rc->total_packets = 0;
1027 
1028 	if (new_itr != rc->itr) {
1029 		rc->itr = new_itr;
1030 		return true;
1031 	}
1032 
1033 	return false;
1034 }
1035 
1036 /**
1037  * i40e_rx_is_programming_status - check for programming status descriptor
1038  * @qw: qword representing status_error_len in CPU ordering
1039  *
1040  * The value of in the descriptor length field indicate if this
1041  * is a programming status descriptor for flow director or FCoE
1042  * by the value of I40E_RX_PROG_STATUS_DESC_LENGTH, otherwise
1043  * it is a packet descriptor.
1044  **/
1045 static inline bool i40e_rx_is_programming_status(u64 qw)
1046 {
1047 	/* The Rx filter programming status and SPH bit occupy the same
1048 	 * spot in the descriptor. Since we don't support packet split we
1049 	 * can just reuse the bit as an indication that this is a
1050 	 * programming status descriptor.
1051 	 */
1052 	return qw & I40E_RXD_QW1_LENGTH_SPH_MASK;
1053 }
1054 
1055 /**
1056  * i40e_clean_programming_status - clean the programming status descriptor
1057  * @rx_ring: the rx ring that has this descriptor
1058  * @rx_desc: the rx descriptor written back by HW
1059  * @qw: qword representing status_error_len in CPU ordering
1060  *
1061  * Flow director should handle FD_FILTER_STATUS to check its filter programming
1062  * status being successful or not and take actions accordingly. FCoE should
1063  * handle its context/filter programming/invalidation status and take actions.
1064  *
1065  **/
1066 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
1067 					  union i40e_rx_desc *rx_desc,
1068 					  u64 qw)
1069 {
1070 	u32 ntc = rx_ring->next_to_clean + 1;
1071 	u8 id;
1072 
1073 	/* fetch, update, and store next to clean */
1074 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1075 	rx_ring->next_to_clean = ntc;
1076 
1077 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1078 
1079 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
1080 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
1081 
1082 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
1083 		i40e_fd_handle_status(rx_ring, rx_desc, id);
1084 }
1085 
1086 /**
1087  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
1088  * @tx_ring: the tx ring to set up
1089  *
1090  * Return 0 on success, negative on error
1091  **/
1092 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
1093 {
1094 	struct device *dev = tx_ring->dev;
1095 	int bi_size;
1096 
1097 	if (!dev)
1098 		return -ENOMEM;
1099 
1100 	/* warn if we are about to overwrite the pointer */
1101 	WARN_ON(tx_ring->tx_bi);
1102 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
1103 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
1104 	if (!tx_ring->tx_bi)
1105 		goto err;
1106 
1107 	/* round up to nearest 4K */
1108 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
1109 	/* add u32 for head writeback, align after this takes care of
1110 	 * guaranteeing this is at least one cache line in size
1111 	 */
1112 	tx_ring->size += sizeof(u32);
1113 	tx_ring->size = ALIGN(tx_ring->size, 4096);
1114 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
1115 					   &tx_ring->dma, GFP_KERNEL);
1116 	if (!tx_ring->desc) {
1117 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
1118 			 tx_ring->size);
1119 		goto err;
1120 	}
1121 
1122 	tx_ring->next_to_use = 0;
1123 	tx_ring->next_to_clean = 0;
1124 	return 0;
1125 
1126 err:
1127 	kfree(tx_ring->tx_bi);
1128 	tx_ring->tx_bi = NULL;
1129 	return -ENOMEM;
1130 }
1131 
1132 /**
1133  * i40e_clean_rx_ring - Free Rx buffers
1134  * @rx_ring: ring to be cleaned
1135  **/
1136 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1137 {
1138 	unsigned long bi_size;
1139 	u16 i;
1140 
1141 	/* ring already cleared, nothing to do */
1142 	if (!rx_ring->rx_bi)
1143 		return;
1144 
1145 	if (rx_ring->skb) {
1146 		dev_kfree_skb(rx_ring->skb);
1147 		rx_ring->skb = NULL;
1148 	}
1149 
1150 	/* Free all the Rx ring sk_buffs */
1151 	for (i = 0; i < rx_ring->count; i++) {
1152 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
1153 
1154 		if (!rx_bi->page)
1155 			continue;
1156 
1157 		/* Invalidate cache lines that may have been written to by
1158 		 * device so that we avoid corrupting memory.
1159 		 */
1160 		dma_sync_single_range_for_cpu(rx_ring->dev,
1161 					      rx_bi->dma,
1162 					      rx_bi->page_offset,
1163 					      rx_ring->rx_buf_len,
1164 					      DMA_FROM_DEVICE);
1165 
1166 		/* free resources associated with mapping */
1167 		dma_unmap_page_attrs(rx_ring->dev, rx_bi->dma,
1168 				     i40e_rx_pg_size(rx_ring),
1169 				     DMA_FROM_DEVICE,
1170 				     I40E_RX_DMA_ATTR);
1171 
1172 		__page_frag_cache_drain(rx_bi->page, rx_bi->pagecnt_bias);
1173 
1174 		rx_bi->page = NULL;
1175 		rx_bi->page_offset = 0;
1176 	}
1177 
1178 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1179 	memset(rx_ring->rx_bi, 0, bi_size);
1180 
1181 	/* Zero out the descriptor ring */
1182 	memset(rx_ring->desc, 0, rx_ring->size);
1183 
1184 	rx_ring->next_to_alloc = 0;
1185 	rx_ring->next_to_clean = 0;
1186 	rx_ring->next_to_use = 0;
1187 }
1188 
1189 /**
1190  * i40e_free_rx_resources - Free Rx resources
1191  * @rx_ring: ring to clean the resources from
1192  *
1193  * Free all receive software resources
1194  **/
1195 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1196 {
1197 	i40e_clean_rx_ring(rx_ring);
1198 	kfree(rx_ring->rx_bi);
1199 	rx_ring->rx_bi = NULL;
1200 
1201 	if (rx_ring->desc) {
1202 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1203 				  rx_ring->desc, rx_ring->dma);
1204 		rx_ring->desc = NULL;
1205 	}
1206 }
1207 
1208 /**
1209  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1210  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1211  *
1212  * Returns 0 on success, negative on failure
1213  **/
1214 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1215 {
1216 	struct device *dev = rx_ring->dev;
1217 	int bi_size;
1218 
1219 	/* warn if we are about to overwrite the pointer */
1220 	WARN_ON(rx_ring->rx_bi);
1221 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1222 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1223 	if (!rx_ring->rx_bi)
1224 		goto err;
1225 
1226 	u64_stats_init(&rx_ring->syncp);
1227 
1228 	/* Round up to nearest 4K */
1229 	rx_ring->size = rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1230 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1231 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1232 					   &rx_ring->dma, GFP_KERNEL);
1233 
1234 	if (!rx_ring->desc) {
1235 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1236 			 rx_ring->size);
1237 		goto err;
1238 	}
1239 
1240 	rx_ring->next_to_alloc = 0;
1241 	rx_ring->next_to_clean = 0;
1242 	rx_ring->next_to_use = 0;
1243 
1244 	return 0;
1245 err:
1246 	kfree(rx_ring->rx_bi);
1247 	rx_ring->rx_bi = NULL;
1248 	return -ENOMEM;
1249 }
1250 
1251 /**
1252  * i40e_release_rx_desc - Store the new tail and head values
1253  * @rx_ring: ring to bump
1254  * @val: new head index
1255  **/
1256 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1257 {
1258 	rx_ring->next_to_use = val;
1259 
1260 	/* update next to alloc since we have filled the ring */
1261 	rx_ring->next_to_alloc = val;
1262 
1263 	/* Force memory writes to complete before letting h/w
1264 	 * know there are new descriptors to fetch.  (Only
1265 	 * applicable for weak-ordered memory model archs,
1266 	 * such as IA-64).
1267 	 */
1268 	wmb();
1269 	writel(val, rx_ring->tail);
1270 }
1271 
1272 /**
1273  * i40e_rx_offset - Return expected offset into page to access data
1274  * @rx_ring: Ring we are requesting offset of
1275  *
1276  * Returns the offset value for ring into the data buffer.
1277  */
1278 static inline unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
1279 {
1280 	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
1281 }
1282 
1283 /**
1284  * i40e_alloc_mapped_page - recycle or make a new page
1285  * @rx_ring: ring to use
1286  * @bi: rx_buffer struct to modify
1287  *
1288  * Returns true if the page was successfully allocated or
1289  * reused.
1290  **/
1291 static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
1292 				   struct i40e_rx_buffer *bi)
1293 {
1294 	struct page *page = bi->page;
1295 	dma_addr_t dma;
1296 
1297 	/* since we are recycling buffers we should seldom need to alloc */
1298 	if (likely(page)) {
1299 		rx_ring->rx_stats.page_reuse_count++;
1300 		return true;
1301 	}
1302 
1303 	/* alloc new page for storage */
1304 	page = dev_alloc_pages(i40e_rx_pg_order(rx_ring));
1305 	if (unlikely(!page)) {
1306 		rx_ring->rx_stats.alloc_page_failed++;
1307 		return false;
1308 	}
1309 
1310 	/* map page for use */
1311 	dma = dma_map_page_attrs(rx_ring->dev, page, 0,
1312 				 i40e_rx_pg_size(rx_ring),
1313 				 DMA_FROM_DEVICE,
1314 				 I40E_RX_DMA_ATTR);
1315 
1316 	/* if mapping failed free memory back to system since
1317 	 * there isn't much point in holding memory we can't use
1318 	 */
1319 	if (dma_mapping_error(rx_ring->dev, dma)) {
1320 		__free_pages(page, i40e_rx_pg_order(rx_ring));
1321 		rx_ring->rx_stats.alloc_page_failed++;
1322 		return false;
1323 	}
1324 
1325 	bi->dma = dma;
1326 	bi->page = page;
1327 	bi->page_offset = i40e_rx_offset(rx_ring);
1328 
1329 	/* initialize pagecnt_bias to 1 representing we fully own page */
1330 	bi->pagecnt_bias = 1;
1331 
1332 	return true;
1333 }
1334 
1335 /**
1336  * i40e_receive_skb - Send a completed packet up the stack
1337  * @rx_ring:  rx ring in play
1338  * @skb: packet to send up
1339  * @vlan_tag: vlan tag for packet
1340  **/
1341 static void i40e_receive_skb(struct i40e_ring *rx_ring,
1342 			     struct sk_buff *skb, u16 vlan_tag)
1343 {
1344 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1345 
1346 	if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
1347 	    (vlan_tag & VLAN_VID_MASK))
1348 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1349 
1350 	napi_gro_receive(&q_vector->napi, skb);
1351 }
1352 
1353 /**
1354  * i40e_alloc_rx_buffers - Replace used receive buffers
1355  * @rx_ring: ring to place buffers on
1356  * @cleaned_count: number of buffers to replace
1357  *
1358  * Returns false if all allocations were successful, true if any fail
1359  **/
1360 bool i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1361 {
1362 	u16 ntu = rx_ring->next_to_use;
1363 	union i40e_rx_desc *rx_desc;
1364 	struct i40e_rx_buffer *bi;
1365 
1366 	/* do nothing if no valid netdev defined */
1367 	if (!rx_ring->netdev || !cleaned_count)
1368 		return false;
1369 
1370 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
1371 	bi = &rx_ring->rx_bi[ntu];
1372 
1373 	do {
1374 		if (!i40e_alloc_mapped_page(rx_ring, bi))
1375 			goto no_buffers;
1376 
1377 		/* sync the buffer for use by the device */
1378 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
1379 						 bi->page_offset,
1380 						 rx_ring->rx_buf_len,
1381 						 DMA_FROM_DEVICE);
1382 
1383 		/* Refresh the desc even if buffer_addrs didn't change
1384 		 * because each write-back erases this info.
1385 		 */
1386 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
1387 
1388 		rx_desc++;
1389 		bi++;
1390 		ntu++;
1391 		if (unlikely(ntu == rx_ring->count)) {
1392 			rx_desc = I40E_RX_DESC(rx_ring, 0);
1393 			bi = rx_ring->rx_bi;
1394 			ntu = 0;
1395 		}
1396 
1397 		/* clear the status bits for the next_to_use descriptor */
1398 		rx_desc->wb.qword1.status_error_len = 0;
1399 
1400 		cleaned_count--;
1401 	} while (cleaned_count);
1402 
1403 	if (rx_ring->next_to_use != ntu)
1404 		i40e_release_rx_desc(rx_ring, ntu);
1405 
1406 	return false;
1407 
1408 no_buffers:
1409 	if (rx_ring->next_to_use != ntu)
1410 		i40e_release_rx_desc(rx_ring, ntu);
1411 
1412 	/* make sure to come back via polling to try again after
1413 	 * allocation failure
1414 	 */
1415 	return true;
1416 }
1417 
1418 /**
1419  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1420  * @vsi: the VSI we care about
1421  * @skb: skb currently being received and modified
1422  * @rx_desc: the receive descriptor
1423  **/
1424 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1425 				    struct sk_buff *skb,
1426 				    union i40e_rx_desc *rx_desc)
1427 {
1428 	struct i40e_rx_ptype_decoded decoded;
1429 	u32 rx_error, rx_status;
1430 	bool ipv4, ipv6;
1431 	u8 ptype;
1432 	u64 qword;
1433 
1434 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1435 	ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >> I40E_RXD_QW1_PTYPE_SHIFT;
1436 	rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1437 		   I40E_RXD_QW1_ERROR_SHIFT;
1438 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1439 		    I40E_RXD_QW1_STATUS_SHIFT;
1440 	decoded = decode_rx_desc_ptype(ptype);
1441 
1442 	skb->ip_summed = CHECKSUM_NONE;
1443 
1444 	skb_checksum_none_assert(skb);
1445 
1446 	/* Rx csum enabled and ip headers found? */
1447 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1448 		return;
1449 
1450 	/* did the hardware decode the packet and checksum? */
1451 	if (!(rx_status & BIT(I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1452 		return;
1453 
1454 	/* both known and outer_ip must be set for the below code to work */
1455 	if (!(decoded.known && decoded.outer_ip))
1456 		return;
1457 
1458 	ipv4 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1459 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4);
1460 	ipv6 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1461 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6);
1462 
1463 	if (ipv4 &&
1464 	    (rx_error & (BIT(I40E_RX_DESC_ERROR_IPE_SHIFT) |
1465 			 BIT(I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1466 		goto checksum_fail;
1467 
1468 	/* likely incorrect csum if alternate IP extension headers found */
1469 	if (ipv6 &&
1470 	    rx_status & BIT(I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1471 		/* don't increment checksum err here, non-fatal err */
1472 		return;
1473 
1474 	/* there was some L4 error, count error and punt packet to the stack */
1475 	if (rx_error & BIT(I40E_RX_DESC_ERROR_L4E_SHIFT))
1476 		goto checksum_fail;
1477 
1478 	/* handle packets that were not able to be checksummed due
1479 	 * to arrival speed, in this case the stack can compute
1480 	 * the csum.
1481 	 */
1482 	if (rx_error & BIT(I40E_RX_DESC_ERROR_PPRS_SHIFT))
1483 		return;
1484 
1485 	/* If there is an outer header present that might contain a checksum
1486 	 * we need to bump the checksum level by 1 to reflect the fact that
1487 	 * we are indicating we validated the inner checksum.
1488 	 */
1489 	if (decoded.tunnel_type >= I40E_RX_PTYPE_TUNNEL_IP_GRENAT)
1490 		skb->csum_level = 1;
1491 
1492 	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
1493 	switch (decoded.inner_prot) {
1494 	case I40E_RX_PTYPE_INNER_PROT_TCP:
1495 	case I40E_RX_PTYPE_INNER_PROT_UDP:
1496 	case I40E_RX_PTYPE_INNER_PROT_SCTP:
1497 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1498 		/* fall though */
1499 	default:
1500 		break;
1501 	}
1502 
1503 	return;
1504 
1505 checksum_fail:
1506 	vsi->back->hw_csum_rx_error++;
1507 }
1508 
1509 /**
1510  * i40e_ptype_to_htype - get a hash type
1511  * @ptype: the ptype value from the descriptor
1512  *
1513  * Returns a hash type to be used by skb_set_hash
1514  **/
1515 static inline int i40e_ptype_to_htype(u8 ptype)
1516 {
1517 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1518 
1519 	if (!decoded.known)
1520 		return PKT_HASH_TYPE_NONE;
1521 
1522 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1523 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1524 		return PKT_HASH_TYPE_L4;
1525 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1526 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1527 		return PKT_HASH_TYPE_L3;
1528 	else
1529 		return PKT_HASH_TYPE_L2;
1530 }
1531 
1532 /**
1533  * i40e_rx_hash - set the hash value in the skb
1534  * @ring: descriptor ring
1535  * @rx_desc: specific descriptor
1536  **/
1537 static inline void i40e_rx_hash(struct i40e_ring *ring,
1538 				union i40e_rx_desc *rx_desc,
1539 				struct sk_buff *skb,
1540 				u8 rx_ptype)
1541 {
1542 	u32 hash;
1543 	const __le64 rss_mask =
1544 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1545 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1546 
1547 	if (!(ring->netdev->features & NETIF_F_RXHASH))
1548 		return;
1549 
1550 	if ((rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask) {
1551 		hash = le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1552 		skb_set_hash(skb, hash, i40e_ptype_to_htype(rx_ptype));
1553 	}
1554 }
1555 
1556 /**
1557  * i40e_process_skb_fields - Populate skb header fields from Rx descriptor
1558  * @rx_ring: rx descriptor ring packet is being transacted on
1559  * @rx_desc: pointer to the EOP Rx descriptor
1560  * @skb: pointer to current skb being populated
1561  * @rx_ptype: the packet type decoded by hardware
1562  *
1563  * This function checks the ring, descriptor, and packet information in
1564  * order to populate the hash, checksum, VLAN, protocol, and
1565  * other fields within the skb.
1566  **/
1567 static inline
1568 void i40e_process_skb_fields(struct i40e_ring *rx_ring,
1569 			     union i40e_rx_desc *rx_desc, struct sk_buff *skb,
1570 			     u8 rx_ptype)
1571 {
1572 	u64 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1573 	u32 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1574 			I40E_RXD_QW1_STATUS_SHIFT;
1575 	u32 tsynvalid = rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK;
1576 	u32 tsyn = (rx_status & I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1577 		   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT;
1578 
1579 	if (unlikely(tsynvalid))
1580 		i40e_ptp_rx_hwtstamp(rx_ring->vsi->back, skb, tsyn);
1581 
1582 	i40e_rx_hash(rx_ring, rx_desc, skb, rx_ptype);
1583 
1584 	i40e_rx_checksum(rx_ring->vsi, skb, rx_desc);
1585 
1586 	skb_record_rx_queue(skb, rx_ring->queue_index);
1587 
1588 	/* modifies the skb - consumes the enet header */
1589 	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1590 }
1591 
1592 /**
1593  * i40e_cleanup_headers - Correct empty headers
1594  * @rx_ring: rx descriptor ring packet is being transacted on
1595  * @skb: pointer to current skb being fixed
1596  *
1597  * Also address the case where we are pulling data in on pages only
1598  * and as such no data is present in the skb header.
1599  *
1600  * In addition if skb is not at least 60 bytes we need to pad it so that
1601  * it is large enough to qualify as a valid Ethernet frame.
1602  *
1603  * Returns true if an error was encountered and skb was freed.
1604  **/
1605 static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb)
1606 {
1607 	/* if eth_skb_pad returns an error the skb was freed */
1608 	if (eth_skb_pad(skb))
1609 		return true;
1610 
1611 	return false;
1612 }
1613 
1614 /**
1615  * i40e_reuse_rx_page - page flip buffer and store it back on the ring
1616  * @rx_ring: rx descriptor ring to store buffers on
1617  * @old_buff: donor buffer to have page reused
1618  *
1619  * Synchronizes page for reuse by the adapter
1620  **/
1621 static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
1622 			       struct i40e_rx_buffer *old_buff)
1623 {
1624 	struct i40e_rx_buffer *new_buff;
1625 	u16 nta = rx_ring->next_to_alloc;
1626 
1627 	new_buff = &rx_ring->rx_bi[nta];
1628 
1629 	/* update, and store next to alloc */
1630 	nta++;
1631 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
1632 
1633 	/* transfer page from old buffer to new buffer */
1634 	new_buff->dma		= old_buff->dma;
1635 	new_buff->page		= old_buff->page;
1636 	new_buff->page_offset	= old_buff->page_offset;
1637 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
1638 }
1639 
1640 /**
1641  * i40e_page_is_reusable - check if any reuse is possible
1642  * @page: page struct to check
1643  *
1644  * A page is not reusable if it was allocated under low memory
1645  * conditions, or it's not in the same NUMA node as this CPU.
1646  */
1647 static inline bool i40e_page_is_reusable(struct page *page)
1648 {
1649 	return (page_to_nid(page) == numa_mem_id()) &&
1650 		!page_is_pfmemalloc(page);
1651 }
1652 
1653 /**
1654  * i40e_can_reuse_rx_page - Determine if this page can be reused by
1655  * the adapter for another receive
1656  *
1657  * @rx_buffer: buffer containing the page
1658  *
1659  * If page is reusable, rx_buffer->page_offset is adjusted to point to
1660  * an unused region in the page.
1661  *
1662  * For small pages, @truesize will be a constant value, half the size
1663  * of the memory at page.  We'll attempt to alternate between high and
1664  * low halves of the page, with one half ready for use by the hardware
1665  * and the other half being consumed by the stack.  We use the page
1666  * ref count to determine whether the stack has finished consuming the
1667  * portion of this page that was passed up with a previous packet.  If
1668  * the page ref count is >1, we'll assume the "other" half page is
1669  * still busy, and this page cannot be reused.
1670  *
1671  * For larger pages, @truesize will be the actual space used by the
1672  * received packet (adjusted upward to an even multiple of the cache
1673  * line size).  This will advance through the page by the amount
1674  * actually consumed by the received packets while there is still
1675  * space for a buffer.  Each region of larger pages will be used at
1676  * most once, after which the page will not be reused.
1677  *
1678  * In either case, if the page is reusable its refcount is increased.
1679  **/
1680 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer)
1681 {
1682 	unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
1683 	struct page *page = rx_buffer->page;
1684 
1685 	/* Is any reuse possible? */
1686 	if (unlikely(!i40e_page_is_reusable(page)))
1687 		return false;
1688 
1689 #if (PAGE_SIZE < 8192)
1690 	/* if we are only owner of page we can reuse it */
1691 	if (unlikely((page_count(page) - pagecnt_bias) > 1))
1692 		return false;
1693 #else
1694 #define I40E_LAST_OFFSET \
1695 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - I40E_RXBUFFER_2048)
1696 	if (rx_buffer->page_offset > I40E_LAST_OFFSET)
1697 		return false;
1698 #endif
1699 
1700 	/* If we have drained the page fragment pool we need to update
1701 	 * the pagecnt_bias and page count so that we fully restock the
1702 	 * number of references the driver holds.
1703 	 */
1704 	if (unlikely(!pagecnt_bias)) {
1705 		page_ref_add(page, USHRT_MAX);
1706 		rx_buffer->pagecnt_bias = USHRT_MAX;
1707 	}
1708 
1709 	return true;
1710 }
1711 
1712 /**
1713  * i40e_add_rx_frag - Add contents of Rx buffer to sk_buff
1714  * @rx_ring: rx descriptor ring to transact packets on
1715  * @rx_buffer: buffer containing page to add
1716  * @skb: sk_buff to place the data into
1717  * @size: packet length from rx_desc
1718  *
1719  * This function will add the data contained in rx_buffer->page to the skb.
1720  * It will just attach the page as a frag to the skb.
1721  *
1722  * The function will then update the page offset.
1723  **/
1724 static void i40e_add_rx_frag(struct i40e_ring *rx_ring,
1725 			     struct i40e_rx_buffer *rx_buffer,
1726 			     struct sk_buff *skb,
1727 			     unsigned int size)
1728 {
1729 #if (PAGE_SIZE < 8192)
1730 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1731 #else
1732 	unsigned int truesize = SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring));
1733 #endif
1734 
1735 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
1736 			rx_buffer->page_offset, size, truesize);
1737 
1738 	/* page is being used so we must update the page offset */
1739 #if (PAGE_SIZE < 8192)
1740 	rx_buffer->page_offset ^= truesize;
1741 #else
1742 	rx_buffer->page_offset += truesize;
1743 #endif
1744 }
1745 
1746 /**
1747  * i40e_get_rx_buffer - Fetch Rx buffer and synchronize data for use
1748  * @rx_ring: rx descriptor ring to transact packets on
1749  * @size: size of buffer to add to skb
1750  *
1751  * This function will pull an Rx buffer from the ring and synchronize it
1752  * for use by the CPU.
1753  */
1754 static struct i40e_rx_buffer *i40e_get_rx_buffer(struct i40e_ring *rx_ring,
1755 						 const unsigned int size)
1756 {
1757 	struct i40e_rx_buffer *rx_buffer;
1758 
1759 	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
1760 	prefetchw(rx_buffer->page);
1761 
1762 	/* we are reusing so sync this buffer for CPU use */
1763 	dma_sync_single_range_for_cpu(rx_ring->dev,
1764 				      rx_buffer->dma,
1765 				      rx_buffer->page_offset,
1766 				      size,
1767 				      DMA_FROM_DEVICE);
1768 
1769 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
1770 	rx_buffer->pagecnt_bias--;
1771 
1772 	return rx_buffer;
1773 }
1774 
1775 /**
1776  * i40e_construct_skb - Allocate skb and populate it
1777  * @rx_ring: rx descriptor ring to transact packets on
1778  * @rx_buffer: rx buffer to pull data from
1779  * @size: size of buffer to add to skb
1780  *
1781  * This function allocates an skb.  It then populates it with the page
1782  * data from the current receive descriptor, taking care to set up the
1783  * skb correctly.
1784  */
1785 static struct sk_buff *i40e_construct_skb(struct i40e_ring *rx_ring,
1786 					  struct i40e_rx_buffer *rx_buffer,
1787 					  unsigned int size)
1788 {
1789 	void *va = page_address(rx_buffer->page) + rx_buffer->page_offset;
1790 #if (PAGE_SIZE < 8192)
1791 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1792 #else
1793 	unsigned int truesize = SKB_DATA_ALIGN(size);
1794 #endif
1795 	unsigned int headlen;
1796 	struct sk_buff *skb;
1797 
1798 	/* prefetch first cache line of first page */
1799 	prefetch(va);
1800 #if L1_CACHE_BYTES < 128
1801 	prefetch(va + L1_CACHE_BYTES);
1802 #endif
1803 
1804 	/* allocate a skb to store the frags */
1805 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
1806 			       I40E_RX_HDR_SIZE,
1807 			       GFP_ATOMIC | __GFP_NOWARN);
1808 	if (unlikely(!skb))
1809 		return NULL;
1810 
1811 	/* Determine available headroom for copy */
1812 	headlen = size;
1813 	if (headlen > I40E_RX_HDR_SIZE)
1814 		headlen = eth_get_headlen(va, I40E_RX_HDR_SIZE);
1815 
1816 	/* align pull length to size of long to optimize memcpy performance */
1817 	memcpy(__skb_put(skb, headlen), va, ALIGN(headlen, sizeof(long)));
1818 
1819 	/* update all of the pointers */
1820 	size -= headlen;
1821 	if (size) {
1822 		skb_add_rx_frag(skb, 0, rx_buffer->page,
1823 				rx_buffer->page_offset + headlen,
1824 				size, truesize);
1825 
1826 		/* buffer is used by skb, update page_offset */
1827 #if (PAGE_SIZE < 8192)
1828 		rx_buffer->page_offset ^= truesize;
1829 #else
1830 		rx_buffer->page_offset += truesize;
1831 #endif
1832 	} else {
1833 		/* buffer is unused, reset bias back to rx_buffer */
1834 		rx_buffer->pagecnt_bias++;
1835 	}
1836 
1837 	return skb;
1838 }
1839 
1840 /**
1841  * i40e_build_skb - Build skb around an existing buffer
1842  * @rx_ring: Rx descriptor ring to transact packets on
1843  * @rx_buffer: Rx buffer to pull data from
1844  * @size: size of buffer to add to skb
1845  *
1846  * This function builds an skb around an existing Rx buffer, taking care
1847  * to set up the skb correctly and avoid any memcpy overhead.
1848  */
1849 static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
1850 				      struct i40e_rx_buffer *rx_buffer,
1851 				      unsigned int size)
1852 {
1853 	void *va = page_address(rx_buffer->page) + rx_buffer->page_offset;
1854 #if (PAGE_SIZE < 8192)
1855 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1856 #else
1857 	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
1858 				SKB_DATA_ALIGN(I40E_SKB_PAD + size);
1859 #endif
1860 	struct sk_buff *skb;
1861 
1862 	/* prefetch first cache line of first page */
1863 	prefetch(va);
1864 #if L1_CACHE_BYTES < 128
1865 	prefetch(va + L1_CACHE_BYTES);
1866 #endif
1867 	/* build an skb around the page buffer */
1868 	skb = build_skb(va - I40E_SKB_PAD, truesize);
1869 	if (unlikely(!skb))
1870 		return NULL;
1871 
1872 	/* update pointers within the skb to store the data */
1873 	skb_reserve(skb, I40E_SKB_PAD);
1874 	__skb_put(skb, size);
1875 
1876 	/* buffer is used by skb, update page_offset */
1877 #if (PAGE_SIZE < 8192)
1878 	rx_buffer->page_offset ^= truesize;
1879 #else
1880 	rx_buffer->page_offset += truesize;
1881 #endif
1882 
1883 	return skb;
1884 }
1885 
1886 /**
1887  * i40e_put_rx_buffer - Clean up used buffer and either recycle or free
1888  * @rx_ring: rx descriptor ring to transact packets on
1889  * @rx_buffer: rx buffer to pull data from
1890  *
1891  * This function will clean up the contents of the rx_buffer.  It will
1892  * either recycle the bufer or unmap it and free the associated resources.
1893  */
1894 static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
1895 			       struct i40e_rx_buffer *rx_buffer)
1896 {
1897 	if (i40e_can_reuse_rx_page(rx_buffer)) {
1898 		/* hand second half of page back to the ring */
1899 		i40e_reuse_rx_page(rx_ring, rx_buffer);
1900 		rx_ring->rx_stats.page_reuse_count++;
1901 	} else {
1902 		/* we are not reusing the buffer so unmap it */
1903 		dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
1904 				     i40e_rx_pg_size(rx_ring),
1905 				     DMA_FROM_DEVICE, I40E_RX_DMA_ATTR);
1906 		__page_frag_cache_drain(rx_buffer->page,
1907 					rx_buffer->pagecnt_bias);
1908 	}
1909 
1910 	/* clear contents of buffer_info */
1911 	rx_buffer->page = NULL;
1912 }
1913 
1914 /**
1915  * i40e_is_non_eop - process handling of non-EOP buffers
1916  * @rx_ring: Rx ring being processed
1917  * @rx_desc: Rx descriptor for current buffer
1918  * @skb: Current socket buffer containing buffer in progress
1919  *
1920  * This function updates next to clean.  If the buffer is an EOP buffer
1921  * this function exits returning false, otherwise it will place the
1922  * sk_buff in the next buffer to be chained and return true indicating
1923  * that this is in fact a non-EOP buffer.
1924  **/
1925 static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
1926 			    union i40e_rx_desc *rx_desc,
1927 			    struct sk_buff *skb)
1928 {
1929 	u32 ntc = rx_ring->next_to_clean + 1;
1930 
1931 	/* fetch, update, and store next to clean */
1932 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1933 	rx_ring->next_to_clean = ntc;
1934 
1935 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1936 
1937 	/* if we are the last buffer then there is nothing else to do */
1938 #define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
1939 	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))
1940 		return false;
1941 
1942 	rx_ring->rx_stats.non_eop_descs++;
1943 
1944 	return true;
1945 }
1946 
1947 /**
1948  * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1949  * @rx_ring: rx descriptor ring to transact packets on
1950  * @budget: Total limit on number of packets to process
1951  *
1952  * This function provides a "bounce buffer" approach to Rx interrupt
1953  * processing.  The advantage to this is that on systems that have
1954  * expensive overhead for IOMMU access this provides a means of avoiding
1955  * it by maintaining the mapping of the page to the system.
1956  *
1957  * Returns amount of work completed
1958  **/
1959 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
1960 {
1961 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1962 	struct sk_buff *skb = rx_ring->skb;
1963 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1964 	bool failure = false;
1965 
1966 	while (likely(total_rx_packets < budget)) {
1967 		struct i40e_rx_buffer *rx_buffer;
1968 		union i40e_rx_desc *rx_desc;
1969 		unsigned int size;
1970 		u16 vlan_tag;
1971 		u8 rx_ptype;
1972 		u64 qword;
1973 
1974 		/* return some buffers to hardware, one at a time is too slow */
1975 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1976 			failure = failure ||
1977 				  i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1978 			cleaned_count = 0;
1979 		}
1980 
1981 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
1982 
1983 		/* status_error_len will always be zero for unused descriptors
1984 		 * because it's cleared in cleanup, and overlaps with hdr_addr
1985 		 * which is always zero because packet split isn't used, if the
1986 		 * hardware wrote DD then the length will be non-zero
1987 		 */
1988 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1989 
1990 		/* This memory barrier is needed to keep us from reading
1991 		 * any other fields out of the rx_desc until we have
1992 		 * verified the descriptor has been written back.
1993 		 */
1994 		dma_rmb();
1995 
1996 		if (unlikely(i40e_rx_is_programming_status(qword))) {
1997 			i40e_clean_programming_status(rx_ring, rx_desc, qword);
1998 			continue;
1999 		}
2000 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
2001 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
2002 		if (!size)
2003 			break;
2004 
2005 		i40e_trace(clean_rx_irq, rx_ring, rx_desc, skb);
2006 		rx_buffer = i40e_get_rx_buffer(rx_ring, size);
2007 
2008 		/* retrieve a buffer from the ring */
2009 		if (skb)
2010 			i40e_add_rx_frag(rx_ring, rx_buffer, skb, size);
2011 		else if (ring_uses_build_skb(rx_ring))
2012 			skb = i40e_build_skb(rx_ring, rx_buffer, size);
2013 		else
2014 			skb = i40e_construct_skb(rx_ring, rx_buffer, size);
2015 
2016 		/* exit if we failed to retrieve a buffer */
2017 		if (!skb) {
2018 			rx_ring->rx_stats.alloc_buff_failed++;
2019 			rx_buffer->pagecnt_bias++;
2020 			break;
2021 		}
2022 
2023 		i40e_put_rx_buffer(rx_ring, rx_buffer);
2024 		cleaned_count++;
2025 
2026 		if (i40e_is_non_eop(rx_ring, rx_desc, skb))
2027 			continue;
2028 
2029 		/* ERR_MASK will only have valid bits if EOP set, and
2030 		 * what we are doing here is actually checking
2031 		 * I40E_RX_DESC_ERROR_RXE_SHIFT, since it is the zeroth bit in
2032 		 * the error field
2033 		 */
2034 		if (unlikely(i40e_test_staterr(rx_desc, BIT(I40E_RXD_QW1_ERROR_SHIFT)))) {
2035 			dev_kfree_skb_any(skb);
2036 			skb = NULL;
2037 			continue;
2038 		}
2039 
2040 		if (i40e_cleanup_headers(rx_ring, skb)) {
2041 			skb = NULL;
2042 			continue;
2043 		}
2044 
2045 		/* probably a little skewed due to removing CRC */
2046 		total_rx_bytes += skb->len;
2047 
2048 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2049 		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
2050 			   I40E_RXD_QW1_PTYPE_SHIFT;
2051 
2052 		/* populate checksum, VLAN, and protocol */
2053 		i40e_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
2054 
2055 		vlan_tag = (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) ?
2056 			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;
2057 
2058 		i40e_trace(clean_rx_irq_rx, rx_ring, rx_desc, skb);
2059 		i40e_receive_skb(rx_ring, skb, vlan_tag);
2060 		skb = NULL;
2061 
2062 		/* update budget accounting */
2063 		total_rx_packets++;
2064 	}
2065 
2066 	rx_ring->skb = skb;
2067 
2068 	u64_stats_update_begin(&rx_ring->syncp);
2069 	rx_ring->stats.packets += total_rx_packets;
2070 	rx_ring->stats.bytes += total_rx_bytes;
2071 	u64_stats_update_end(&rx_ring->syncp);
2072 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
2073 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
2074 
2075 	/* guarantee a trip back through this routine if there was a failure */
2076 	return failure ? budget : total_rx_packets;
2077 }
2078 
2079 static u32 i40e_buildreg_itr(const int type, const u16 itr)
2080 {
2081 	u32 val;
2082 
2083 	val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
2084 	      /* Don't clear PBA because that can cause lost interrupts that
2085 	       * came in while we were cleaning/polling
2086 	       */
2087 	      (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
2088 	      (itr << I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT);
2089 
2090 	return val;
2091 }
2092 
2093 /* a small macro to shorten up some long lines */
2094 #define INTREG I40E_PFINT_DYN_CTLN
2095 static inline int get_rx_itr(struct i40e_vsi *vsi, int idx)
2096 {
2097 	return vsi->rx_rings[idx]->rx_itr_setting;
2098 }
2099 
2100 static inline int get_tx_itr(struct i40e_vsi *vsi, int idx)
2101 {
2102 	return vsi->tx_rings[idx]->tx_itr_setting;
2103 }
2104 
2105 /**
2106  * i40e_update_enable_itr - Update itr and re-enable MSIX interrupt
2107  * @vsi: the VSI we care about
2108  * @q_vector: q_vector for which itr is being updated and interrupt enabled
2109  *
2110  **/
2111 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
2112 					  struct i40e_q_vector *q_vector)
2113 {
2114 	struct i40e_hw *hw = &vsi->back->hw;
2115 	bool rx = false, tx = false;
2116 	u32 rxval, txval;
2117 	int vector;
2118 	int idx = q_vector->v_idx;
2119 	int rx_itr_setting, tx_itr_setting;
2120 
2121 	vector = (q_vector->v_idx + vsi->base_vector);
2122 
2123 	/* avoid dynamic calculation if in countdown mode OR if
2124 	 * all dynamic is disabled
2125 	 */
2126 	rxval = txval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
2127 
2128 	rx_itr_setting = get_rx_itr(vsi, idx);
2129 	tx_itr_setting = get_tx_itr(vsi, idx);
2130 
2131 	if (q_vector->itr_countdown > 0 ||
2132 	    (!ITR_IS_DYNAMIC(rx_itr_setting) &&
2133 	     !ITR_IS_DYNAMIC(tx_itr_setting))) {
2134 		goto enable_int;
2135 	}
2136 
2137 	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
2138 		rx = i40e_set_new_dynamic_itr(&q_vector->rx);
2139 		rxval = i40e_buildreg_itr(I40E_RX_ITR, q_vector->rx.itr);
2140 	}
2141 
2142 	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
2143 		tx = i40e_set_new_dynamic_itr(&q_vector->tx);
2144 		txval = i40e_buildreg_itr(I40E_TX_ITR, q_vector->tx.itr);
2145 	}
2146 
2147 	if (rx || tx) {
2148 		/* get the higher of the two ITR adjustments and
2149 		 * use the same value for both ITR registers
2150 		 * when in adaptive mode (Rx and/or Tx)
2151 		 */
2152 		u16 itr = max(q_vector->tx.itr, q_vector->rx.itr);
2153 
2154 		q_vector->tx.itr = q_vector->rx.itr = itr;
2155 		txval = i40e_buildreg_itr(I40E_TX_ITR, itr);
2156 		tx = true;
2157 		rxval = i40e_buildreg_itr(I40E_RX_ITR, itr);
2158 		rx = true;
2159 	}
2160 
2161 	/* only need to enable the interrupt once, but need
2162 	 * to possibly update both ITR values
2163 	 */
2164 	if (rx) {
2165 		/* set the INTENA_MSK_MASK so that this first write
2166 		 * won't actually enable the interrupt, instead just
2167 		 * updating the ITR (it's bit 31 PF and VF)
2168 		 */
2169 		rxval |= BIT(31);
2170 		/* don't check _DOWN because interrupt isn't being enabled */
2171 		wr32(hw, INTREG(vector - 1), rxval);
2172 	}
2173 
2174 enable_int:
2175 	if (!test_bit(__I40E_VSI_DOWN, vsi->state))
2176 		wr32(hw, INTREG(vector - 1), txval);
2177 
2178 	if (q_vector->itr_countdown)
2179 		q_vector->itr_countdown--;
2180 	else
2181 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2182 }
2183 
2184 /**
2185  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
2186  * @napi: napi struct with our devices info in it
2187  * @budget: amount of work driver is allowed to do this pass, in packets
2188  *
2189  * This function will clean all queues associated with a q_vector.
2190  *
2191  * Returns the amount of work done
2192  **/
2193 int i40e_napi_poll(struct napi_struct *napi, int budget)
2194 {
2195 	struct i40e_q_vector *q_vector =
2196 			       container_of(napi, struct i40e_q_vector, napi);
2197 	struct i40e_vsi *vsi = q_vector->vsi;
2198 	struct i40e_ring *ring;
2199 	bool clean_complete = true;
2200 	bool arm_wb = false;
2201 	int budget_per_ring;
2202 	int work_done = 0;
2203 
2204 	if (test_bit(__I40E_VSI_DOWN, vsi->state)) {
2205 		napi_complete(napi);
2206 		return 0;
2207 	}
2208 
2209 	/* Since the actual Tx work is minimal, we can give the Tx a larger
2210 	 * budget and be more aggressive about cleaning up the Tx descriptors.
2211 	 */
2212 	i40e_for_each_ring(ring, q_vector->tx) {
2213 		if (!i40e_clean_tx_irq(vsi, ring, budget)) {
2214 			clean_complete = false;
2215 			continue;
2216 		}
2217 		arm_wb |= ring->arm_wb;
2218 		ring->arm_wb = false;
2219 	}
2220 
2221 	/* Handle case where we are called by netpoll with a budget of 0 */
2222 	if (budget <= 0)
2223 		goto tx_only;
2224 
2225 	/* We attempt to distribute budget to each Rx queue fairly, but don't
2226 	 * allow the budget to go below 1 because that would exit polling early.
2227 	 */
2228 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
2229 
2230 	i40e_for_each_ring(ring, q_vector->rx) {
2231 		int cleaned = i40e_clean_rx_irq(ring, budget_per_ring);
2232 
2233 		work_done += cleaned;
2234 		/* if we clean as many as budgeted, we must not be done */
2235 		if (cleaned >= budget_per_ring)
2236 			clean_complete = false;
2237 	}
2238 
2239 	/* If work not completed, return budget and polling will return */
2240 	if (!clean_complete) {
2241 		const cpumask_t *aff_mask = &q_vector->affinity_mask;
2242 		int cpu_id = smp_processor_id();
2243 
2244 		/* It is possible that the interrupt affinity has changed but,
2245 		 * if the cpu is pegged at 100%, polling will never exit while
2246 		 * traffic continues and the interrupt will be stuck on this
2247 		 * cpu.  We check to make sure affinity is correct before we
2248 		 * continue to poll, otherwise we must stop polling so the
2249 		 * interrupt can move to the correct cpu.
2250 		 */
2251 		if (likely(cpumask_test_cpu(cpu_id, aff_mask) ||
2252 			   !(vsi->back->flags & I40E_FLAG_MSIX_ENABLED))) {
2253 tx_only:
2254 			if (arm_wb) {
2255 				q_vector->tx.ring[0].tx_stats.tx_force_wb++;
2256 				i40e_enable_wb_on_itr(vsi, q_vector);
2257 			}
2258 			return budget;
2259 		}
2260 	}
2261 
2262 	if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR)
2263 		q_vector->arm_wb_state = false;
2264 
2265 	/* Work is done so exit the polling mode and re-enable the interrupt */
2266 	napi_complete_done(napi, work_done);
2267 
2268 	/* If we're prematurely stopping polling to fix the interrupt
2269 	 * affinity we want to make sure polling starts back up so we
2270 	 * issue a call to i40e_force_wb which triggers a SW interrupt.
2271 	 */
2272 	if (!clean_complete)
2273 		i40e_force_wb(vsi, q_vector);
2274 	else if (!(vsi->back->flags & I40E_FLAG_MSIX_ENABLED))
2275 		i40e_irq_dynamic_enable_icr0(vsi->back, false);
2276 	else
2277 		i40e_update_enable_itr(vsi, q_vector);
2278 
2279 	return min(work_done, budget - 1);
2280 }
2281 
2282 /**
2283  * i40e_atr - Add a Flow Director ATR filter
2284  * @tx_ring:  ring to add programming descriptor to
2285  * @skb:      send buffer
2286  * @tx_flags: send tx flags
2287  **/
2288 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
2289 		     u32 tx_flags)
2290 {
2291 	struct i40e_filter_program_desc *fdir_desc;
2292 	struct i40e_pf *pf = tx_ring->vsi->back;
2293 	union {
2294 		unsigned char *network;
2295 		struct iphdr *ipv4;
2296 		struct ipv6hdr *ipv6;
2297 	} hdr;
2298 	struct tcphdr *th;
2299 	unsigned int hlen;
2300 	u32 flex_ptype, dtype_cmd;
2301 	int l4_proto;
2302 	u16 i;
2303 
2304 	/* make sure ATR is enabled */
2305 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
2306 		return;
2307 
2308 	if (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED)
2309 		return;
2310 
2311 	/* if sampling is disabled do nothing */
2312 	if (!tx_ring->atr_sample_rate)
2313 		return;
2314 
2315 	/* Currently only IPv4/IPv6 with TCP is supported */
2316 	if (!(tx_flags & (I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6)))
2317 		return;
2318 
2319 	/* snag network header to get L4 type and address */
2320 	hdr.network = (tx_flags & I40E_TX_FLAGS_UDP_TUNNEL) ?
2321 		      skb_inner_network_header(skb) : skb_network_header(skb);
2322 
2323 	/* Note: tx_flags gets modified to reflect inner protocols in
2324 	 * tx_enable_csum function if encap is enabled.
2325 	 */
2326 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2327 		/* access ihl as u8 to avoid unaligned access on ia64 */
2328 		hlen = (hdr.network[0] & 0x0F) << 2;
2329 		l4_proto = hdr.ipv4->protocol;
2330 	} else {
2331 		hlen = hdr.network - skb->data;
2332 		l4_proto = ipv6_find_hdr(skb, &hlen, IPPROTO_TCP, NULL, NULL);
2333 		hlen -= hdr.network - skb->data;
2334 	}
2335 
2336 	if (l4_proto != IPPROTO_TCP)
2337 		return;
2338 
2339 	th = (struct tcphdr *)(hdr.network + hlen);
2340 
2341 	/* Due to lack of space, no more new filters can be programmed */
2342 	if (th->syn && (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED))
2343 		return;
2344 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED) {
2345 		/* HW ATR eviction will take care of removing filters on FIN
2346 		 * and RST packets.
2347 		 */
2348 		if (th->fin || th->rst)
2349 			return;
2350 	}
2351 
2352 	tx_ring->atr_count++;
2353 
2354 	/* sample on all syn/fin/rst packets or once every atr sample rate */
2355 	if (!th->fin &&
2356 	    !th->syn &&
2357 	    !th->rst &&
2358 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
2359 		return;
2360 
2361 	tx_ring->atr_count = 0;
2362 
2363 	/* grab the next descriptor */
2364 	i = tx_ring->next_to_use;
2365 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
2366 
2367 	i++;
2368 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2369 
2370 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
2371 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
2372 	flex_ptype |= (tx_flags & I40E_TX_FLAGS_IPV4) ?
2373 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
2374 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
2375 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
2376 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
2377 
2378 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
2379 
2380 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
2381 
2382 	dtype_cmd |= (th->fin || th->rst) ?
2383 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
2384 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
2385 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
2386 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
2387 
2388 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
2389 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
2390 
2391 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
2392 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
2393 
2394 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
2395 	if (!(tx_flags & I40E_TX_FLAGS_UDP_TUNNEL))
2396 		dtype_cmd |=
2397 			((u32)I40E_FD_ATR_STAT_IDX(pf->hw.pf_id) <<
2398 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2399 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2400 	else
2401 		dtype_cmd |=
2402 			((u32)I40E_FD_ATR_TUNNEL_STAT_IDX(pf->hw.pf_id) <<
2403 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2404 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2405 
2406 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED)
2407 		dtype_cmd |= I40E_TXD_FLTR_QW1_ATR_MASK;
2408 
2409 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
2410 	fdir_desc->rsvd = cpu_to_le32(0);
2411 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
2412 	fdir_desc->fd_id = cpu_to_le32(0);
2413 }
2414 
2415 /**
2416  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
2417  * @skb:     send buffer
2418  * @tx_ring: ring to send buffer on
2419  * @flags:   the tx flags to be set
2420  *
2421  * Checks the skb and set up correspondingly several generic transmit flags
2422  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2423  *
2424  * Returns error code indicate the frame should be dropped upon error and the
2425  * otherwise  returns 0 to indicate the flags has been set properly.
2426  **/
2427 static inline int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2428 					     struct i40e_ring *tx_ring,
2429 					     u32 *flags)
2430 {
2431 	__be16 protocol = skb->protocol;
2432 	u32  tx_flags = 0;
2433 
2434 	if (protocol == htons(ETH_P_8021Q) &&
2435 	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
2436 		/* When HW VLAN acceleration is turned off by the user the
2437 		 * stack sets the protocol to 8021q so that the driver
2438 		 * can take any steps required to support the SW only
2439 		 * VLAN handling.  In our case the driver doesn't need
2440 		 * to take any further steps so just set the protocol
2441 		 * to the encapsulated ethertype.
2442 		 */
2443 		skb->protocol = vlan_get_protocol(skb);
2444 		goto out;
2445 	}
2446 
2447 	/* if we have a HW VLAN tag being added, default to the HW one */
2448 	if (skb_vlan_tag_present(skb)) {
2449 		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
2450 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2451 	/* else if it is a SW VLAN, check the next protocol and store the tag */
2452 	} else if (protocol == htons(ETH_P_8021Q)) {
2453 		struct vlan_hdr *vhdr, _vhdr;
2454 
2455 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
2456 		if (!vhdr)
2457 			return -EINVAL;
2458 
2459 		protocol = vhdr->h_vlan_encapsulated_proto;
2460 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
2461 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
2462 	}
2463 
2464 	if (!(tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED))
2465 		goto out;
2466 
2467 	/* Insert 802.1p priority into VLAN header */
2468 	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
2469 	    (skb->priority != TC_PRIO_CONTROL)) {
2470 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
2471 		tx_flags |= (skb->priority & 0x7) <<
2472 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
2473 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
2474 			struct vlan_ethhdr *vhdr;
2475 			int rc;
2476 
2477 			rc = skb_cow_head(skb, 0);
2478 			if (rc < 0)
2479 				return rc;
2480 			vhdr = (struct vlan_ethhdr *)skb->data;
2481 			vhdr->h_vlan_TCI = htons(tx_flags >>
2482 						 I40E_TX_FLAGS_VLAN_SHIFT);
2483 		} else {
2484 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2485 		}
2486 	}
2487 
2488 out:
2489 	*flags = tx_flags;
2490 	return 0;
2491 }
2492 
2493 /**
2494  * i40e_tso - set up the tso context descriptor
2495  * @first:    pointer to first Tx buffer for xmit
2496  * @hdr_len:  ptr to the size of the packet header
2497  * @cd_type_cmd_tso_mss: Quad Word 1
2498  *
2499  * Returns 0 if no TSO can happen, 1 if tso is going, or error
2500  **/
2501 static int i40e_tso(struct i40e_tx_buffer *first, u8 *hdr_len,
2502 		    u64 *cd_type_cmd_tso_mss)
2503 {
2504 	struct sk_buff *skb = first->skb;
2505 	u64 cd_cmd, cd_tso_len, cd_mss;
2506 	union {
2507 		struct iphdr *v4;
2508 		struct ipv6hdr *v6;
2509 		unsigned char *hdr;
2510 	} ip;
2511 	union {
2512 		struct tcphdr *tcp;
2513 		struct udphdr *udp;
2514 		unsigned char *hdr;
2515 	} l4;
2516 	u32 paylen, l4_offset;
2517 	u16 gso_segs, gso_size;
2518 	int err;
2519 
2520 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2521 		return 0;
2522 
2523 	if (!skb_is_gso(skb))
2524 		return 0;
2525 
2526 	err = skb_cow_head(skb, 0);
2527 	if (err < 0)
2528 		return err;
2529 
2530 	ip.hdr = skb_network_header(skb);
2531 	l4.hdr = skb_transport_header(skb);
2532 
2533 	/* initialize outer IP header fields */
2534 	if (ip.v4->version == 4) {
2535 		ip.v4->tot_len = 0;
2536 		ip.v4->check = 0;
2537 	} else {
2538 		ip.v6->payload_len = 0;
2539 	}
2540 
2541 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2542 					 SKB_GSO_GRE_CSUM |
2543 					 SKB_GSO_IPXIP4 |
2544 					 SKB_GSO_IPXIP6 |
2545 					 SKB_GSO_UDP_TUNNEL |
2546 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2547 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2548 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2549 			l4.udp->len = 0;
2550 
2551 			/* determine offset of outer transport header */
2552 			l4_offset = l4.hdr - skb->data;
2553 
2554 			/* remove payload length from outer checksum */
2555 			paylen = skb->len - l4_offset;
2556 			csum_replace_by_diff(&l4.udp->check,
2557 					     (__force __wsum)htonl(paylen));
2558 		}
2559 
2560 		/* reset pointers to inner headers */
2561 		ip.hdr = skb_inner_network_header(skb);
2562 		l4.hdr = skb_inner_transport_header(skb);
2563 
2564 		/* initialize inner IP header fields */
2565 		if (ip.v4->version == 4) {
2566 			ip.v4->tot_len = 0;
2567 			ip.v4->check = 0;
2568 		} else {
2569 			ip.v6->payload_len = 0;
2570 		}
2571 	}
2572 
2573 	/* determine offset of inner transport header */
2574 	l4_offset = l4.hdr - skb->data;
2575 
2576 	/* remove payload length from inner checksum */
2577 	paylen = skb->len - l4_offset;
2578 	csum_replace_by_diff(&l4.tcp->check, (__force __wsum)htonl(paylen));
2579 
2580 	/* compute length of segmentation header */
2581 	*hdr_len = (l4.tcp->doff * 4) + l4_offset;
2582 
2583 	/* pull values out of skb_shinfo */
2584 	gso_size = skb_shinfo(skb)->gso_size;
2585 	gso_segs = skb_shinfo(skb)->gso_segs;
2586 
2587 	/* update GSO size and bytecount with header size */
2588 	first->gso_segs = gso_segs;
2589 	first->bytecount += (first->gso_segs - 1) * *hdr_len;
2590 
2591 	/* find the field values */
2592 	cd_cmd = I40E_TX_CTX_DESC_TSO;
2593 	cd_tso_len = skb->len - *hdr_len;
2594 	cd_mss = gso_size;
2595 	*cd_type_cmd_tso_mss |= (cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
2596 				(cd_tso_len << I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
2597 				(cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
2598 	return 1;
2599 }
2600 
2601 /**
2602  * i40e_tsyn - set up the tsyn context descriptor
2603  * @tx_ring:  ptr to the ring to send
2604  * @skb:      ptr to the skb we're sending
2605  * @tx_flags: the collected send information
2606  * @cd_type_cmd_tso_mss: Quad Word 1
2607  *
2608  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
2609  **/
2610 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
2611 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
2612 {
2613 	struct i40e_pf *pf;
2614 
2615 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2616 		return 0;
2617 
2618 	/* Tx timestamps cannot be sampled when doing TSO */
2619 	if (tx_flags & I40E_TX_FLAGS_TSO)
2620 		return 0;
2621 
2622 	/* only timestamp the outbound packet if the user has requested it and
2623 	 * we are not already transmitting a packet to be timestamped
2624 	 */
2625 	pf = i40e_netdev_to_pf(tx_ring->netdev);
2626 	if (!(pf->flags & I40E_FLAG_PTP))
2627 		return 0;
2628 
2629 	if (pf->ptp_tx &&
2630 	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, pf->state)) {
2631 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2632 		pf->ptp_tx_skb = skb_get(skb);
2633 	} else {
2634 		return 0;
2635 	}
2636 
2637 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
2638 				I40E_TXD_CTX_QW1_CMD_SHIFT;
2639 
2640 	return 1;
2641 }
2642 
2643 /**
2644  * i40e_tx_enable_csum - Enable Tx checksum offloads
2645  * @skb: send buffer
2646  * @tx_flags: pointer to Tx flags currently set
2647  * @td_cmd: Tx descriptor command bits to set
2648  * @td_offset: Tx descriptor header offsets to set
2649  * @tx_ring: Tx descriptor ring
2650  * @cd_tunneling: ptr to context desc bits
2651  **/
2652 static int i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
2653 			       u32 *td_cmd, u32 *td_offset,
2654 			       struct i40e_ring *tx_ring,
2655 			       u32 *cd_tunneling)
2656 {
2657 	union {
2658 		struct iphdr *v4;
2659 		struct ipv6hdr *v6;
2660 		unsigned char *hdr;
2661 	} ip;
2662 	union {
2663 		struct tcphdr *tcp;
2664 		struct udphdr *udp;
2665 		unsigned char *hdr;
2666 	} l4;
2667 	unsigned char *exthdr;
2668 	u32 offset, cmd = 0;
2669 	__be16 frag_off;
2670 	u8 l4_proto = 0;
2671 
2672 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2673 		return 0;
2674 
2675 	ip.hdr = skb_network_header(skb);
2676 	l4.hdr = skb_transport_header(skb);
2677 
2678 	/* compute outer L2 header size */
2679 	offset = ((ip.hdr - skb->data) / 2) << I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
2680 
2681 	if (skb->encapsulation) {
2682 		u32 tunnel = 0;
2683 		/* define outer network header type */
2684 		if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2685 			tunnel |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2686 				  I40E_TX_CTX_EXT_IP_IPV4 :
2687 				  I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
2688 
2689 			l4_proto = ip.v4->protocol;
2690 		} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2691 			tunnel |= I40E_TX_CTX_EXT_IP_IPV6;
2692 
2693 			exthdr = ip.hdr + sizeof(*ip.v6);
2694 			l4_proto = ip.v6->nexthdr;
2695 			if (l4.hdr != exthdr)
2696 				ipv6_skip_exthdr(skb, exthdr - skb->data,
2697 						 &l4_proto, &frag_off);
2698 		}
2699 
2700 		/* define outer transport */
2701 		switch (l4_proto) {
2702 		case IPPROTO_UDP:
2703 			tunnel |= I40E_TXD_CTX_UDP_TUNNELING;
2704 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2705 			break;
2706 		case IPPROTO_GRE:
2707 			tunnel |= I40E_TXD_CTX_GRE_TUNNELING;
2708 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2709 			break;
2710 		case IPPROTO_IPIP:
2711 		case IPPROTO_IPV6:
2712 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2713 			l4.hdr = skb_inner_network_header(skb);
2714 			break;
2715 		default:
2716 			if (*tx_flags & I40E_TX_FLAGS_TSO)
2717 				return -1;
2718 
2719 			skb_checksum_help(skb);
2720 			return 0;
2721 		}
2722 
2723 		/* compute outer L3 header size */
2724 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
2725 			  I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT;
2726 
2727 		/* switch IP header pointer from outer to inner header */
2728 		ip.hdr = skb_inner_network_header(skb);
2729 
2730 		/* compute tunnel header size */
2731 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
2732 			  I40E_TXD_CTX_QW0_NATLEN_SHIFT;
2733 
2734 		/* indicate if we need to offload outer UDP header */
2735 		if ((*tx_flags & I40E_TX_FLAGS_TSO) &&
2736 		    !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2737 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
2738 			tunnel |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
2739 
2740 		/* record tunnel offload values */
2741 		*cd_tunneling |= tunnel;
2742 
2743 		/* switch L4 header pointer from outer to inner */
2744 		l4.hdr = skb_inner_transport_header(skb);
2745 		l4_proto = 0;
2746 
2747 		/* reset type as we transition from outer to inner headers */
2748 		*tx_flags &= ~(I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6);
2749 		if (ip.v4->version == 4)
2750 			*tx_flags |= I40E_TX_FLAGS_IPV4;
2751 		if (ip.v6->version == 6)
2752 			*tx_flags |= I40E_TX_FLAGS_IPV6;
2753 	}
2754 
2755 	/* Enable IP checksum offloads */
2756 	if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2757 		l4_proto = ip.v4->protocol;
2758 		/* the stack computes the IP header already, the only time we
2759 		 * need the hardware to recompute it is in the case of TSO.
2760 		 */
2761 		cmd |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2762 		       I40E_TX_DESC_CMD_IIPT_IPV4_CSUM :
2763 		       I40E_TX_DESC_CMD_IIPT_IPV4;
2764 	} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2765 		cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
2766 
2767 		exthdr = ip.hdr + sizeof(*ip.v6);
2768 		l4_proto = ip.v6->nexthdr;
2769 		if (l4.hdr != exthdr)
2770 			ipv6_skip_exthdr(skb, exthdr - skb->data,
2771 					 &l4_proto, &frag_off);
2772 	}
2773 
2774 	/* compute inner L3 header size */
2775 	offset |= ((l4.hdr - ip.hdr) / 4) << I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2776 
2777 	/* Enable L4 checksum offloads */
2778 	switch (l4_proto) {
2779 	case IPPROTO_TCP:
2780 		/* enable checksum offloads */
2781 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
2782 		offset |= l4.tcp->doff << I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2783 		break;
2784 	case IPPROTO_SCTP:
2785 		/* enable SCTP checksum offload */
2786 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
2787 		offset |= (sizeof(struct sctphdr) >> 2) <<
2788 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2789 		break;
2790 	case IPPROTO_UDP:
2791 		/* enable UDP checksum offload */
2792 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
2793 		offset |= (sizeof(struct udphdr) >> 2) <<
2794 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2795 		break;
2796 	default:
2797 		if (*tx_flags & I40E_TX_FLAGS_TSO)
2798 			return -1;
2799 		skb_checksum_help(skb);
2800 		return 0;
2801 	}
2802 
2803 	*td_cmd |= cmd;
2804 	*td_offset |= offset;
2805 
2806 	return 1;
2807 }
2808 
2809 /**
2810  * i40e_create_tx_ctx Build the Tx context descriptor
2811  * @tx_ring:  ring to create the descriptor on
2812  * @cd_type_cmd_tso_mss: Quad Word 1
2813  * @cd_tunneling: Quad Word 0 - bits 0-31
2814  * @cd_l2tag2: Quad Word 0 - bits 32-63
2815  **/
2816 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
2817 			       const u64 cd_type_cmd_tso_mss,
2818 			       const u32 cd_tunneling, const u32 cd_l2tag2)
2819 {
2820 	struct i40e_tx_context_desc *context_desc;
2821 	int i = tx_ring->next_to_use;
2822 
2823 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
2824 	    !cd_tunneling && !cd_l2tag2)
2825 		return;
2826 
2827 	/* grab the next descriptor */
2828 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
2829 
2830 	i++;
2831 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2832 
2833 	/* cpu_to_le32 and assign to struct fields */
2834 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2835 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2836 	context_desc->rsvd = cpu_to_le16(0);
2837 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2838 }
2839 
2840 /**
2841  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2842  * @tx_ring: the ring to be checked
2843  * @size:    the size buffer we want to assure is available
2844  *
2845  * Returns -EBUSY if a stop is needed, else 0
2846  **/
2847 int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2848 {
2849 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2850 	/* Memory barrier before checking head and tail */
2851 	smp_mb();
2852 
2853 	/* Check again in a case another CPU has just made room available. */
2854 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2855 		return -EBUSY;
2856 
2857 	/* A reprieve! - use start_queue because it doesn't call schedule */
2858 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
2859 	++tx_ring->tx_stats.restart_queue;
2860 	return 0;
2861 }
2862 
2863 /**
2864  * __i40e_chk_linearize - Check if there are more than 8 buffers per packet
2865  * @skb:      send buffer
2866  *
2867  * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
2868  * and so we need to figure out the cases where we need to linearize the skb.
2869  *
2870  * For TSO we need to count the TSO header and segment payload separately.
2871  * As such we need to check cases where we have 7 fragments or more as we
2872  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2873  * the segment payload in the first descriptor, and another 7 for the
2874  * fragments.
2875  **/
2876 bool __i40e_chk_linearize(struct sk_buff *skb)
2877 {
2878 	const struct skb_frag_struct *frag, *stale;
2879 	int nr_frags, sum;
2880 
2881 	/* no need to check if number of frags is less than 7 */
2882 	nr_frags = skb_shinfo(skb)->nr_frags;
2883 	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
2884 		return false;
2885 
2886 	/* We need to walk through the list and validate that each group
2887 	 * of 6 fragments totals at least gso_size.
2888 	 */
2889 	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
2890 	frag = &skb_shinfo(skb)->frags[0];
2891 
2892 	/* Initialize size to the negative value of gso_size minus 1.  We
2893 	 * use this as the worst case scenerio in which the frag ahead
2894 	 * of us only provides one byte which is why we are limited to 6
2895 	 * descriptors for a single transmit as the header and previous
2896 	 * fragment are already consuming 2 descriptors.
2897 	 */
2898 	sum = 1 - skb_shinfo(skb)->gso_size;
2899 
2900 	/* Add size of frags 0 through 4 to create our initial sum */
2901 	sum += skb_frag_size(frag++);
2902 	sum += skb_frag_size(frag++);
2903 	sum += skb_frag_size(frag++);
2904 	sum += skb_frag_size(frag++);
2905 	sum += skb_frag_size(frag++);
2906 
2907 	/* Walk through fragments adding latest fragment, testing it, and
2908 	 * then removing stale fragments from the sum.
2909 	 */
2910 	stale = &skb_shinfo(skb)->frags[0];
2911 	for (;;) {
2912 		sum += skb_frag_size(frag++);
2913 
2914 		/* if sum is negative we failed to make sufficient progress */
2915 		if (sum < 0)
2916 			return true;
2917 
2918 		if (!nr_frags--)
2919 			break;
2920 
2921 		sum -= skb_frag_size(stale++);
2922 	}
2923 
2924 	return false;
2925 }
2926 
2927 /**
2928  * i40e_tx_map - Build the Tx descriptor
2929  * @tx_ring:  ring to send buffer on
2930  * @skb:      send buffer
2931  * @first:    first buffer info buffer to use
2932  * @tx_flags: collected send information
2933  * @hdr_len:  size of the packet header
2934  * @td_cmd:   the command field in the descriptor
2935  * @td_offset: offset for checksum or crc
2936  **/
2937 static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2938 			       struct i40e_tx_buffer *first, u32 tx_flags,
2939 			       const u8 hdr_len, u32 td_cmd, u32 td_offset)
2940 {
2941 	unsigned int data_len = skb->data_len;
2942 	unsigned int size = skb_headlen(skb);
2943 	struct skb_frag_struct *frag;
2944 	struct i40e_tx_buffer *tx_bi;
2945 	struct i40e_tx_desc *tx_desc;
2946 	u16 i = tx_ring->next_to_use;
2947 	u32 td_tag = 0;
2948 	dma_addr_t dma;
2949 	u16 desc_count = 1;
2950 
2951 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
2952 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
2953 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
2954 			 I40E_TX_FLAGS_VLAN_SHIFT;
2955 	}
2956 
2957 	first->tx_flags = tx_flags;
2958 
2959 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
2960 
2961 	tx_desc = I40E_TX_DESC(tx_ring, i);
2962 	tx_bi = first;
2963 
2964 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
2965 		unsigned int max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
2966 
2967 		if (dma_mapping_error(tx_ring->dev, dma))
2968 			goto dma_error;
2969 
2970 		/* record length, and DMA address */
2971 		dma_unmap_len_set(tx_bi, len, size);
2972 		dma_unmap_addr_set(tx_bi, dma, dma);
2973 
2974 		/* align size to end of page */
2975 		max_data += -dma & (I40E_MAX_READ_REQ_SIZE - 1);
2976 		tx_desc->buffer_addr = cpu_to_le64(dma);
2977 
2978 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
2979 			tx_desc->cmd_type_offset_bsz =
2980 				build_ctob(td_cmd, td_offset,
2981 					   max_data, td_tag);
2982 
2983 			tx_desc++;
2984 			i++;
2985 			desc_count++;
2986 
2987 			if (i == tx_ring->count) {
2988 				tx_desc = I40E_TX_DESC(tx_ring, 0);
2989 				i = 0;
2990 			}
2991 
2992 			dma += max_data;
2993 			size -= max_data;
2994 
2995 			max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
2996 			tx_desc->buffer_addr = cpu_to_le64(dma);
2997 		}
2998 
2999 		if (likely(!data_len))
3000 			break;
3001 
3002 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
3003 							  size, td_tag);
3004 
3005 		tx_desc++;
3006 		i++;
3007 		desc_count++;
3008 
3009 		if (i == tx_ring->count) {
3010 			tx_desc = I40E_TX_DESC(tx_ring, 0);
3011 			i = 0;
3012 		}
3013 
3014 		size = skb_frag_size(frag);
3015 		data_len -= size;
3016 
3017 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
3018 				       DMA_TO_DEVICE);
3019 
3020 		tx_bi = &tx_ring->tx_bi[i];
3021 	}
3022 
3023 	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
3024 
3025 	i++;
3026 	if (i == tx_ring->count)
3027 		i = 0;
3028 
3029 	tx_ring->next_to_use = i;
3030 
3031 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
3032 
3033 	/* write last descriptor with EOP bit */
3034 	td_cmd |= I40E_TX_DESC_CMD_EOP;
3035 
3036 	/* We can OR these values together as they both are checked against
3037 	 * 4 below and at this point desc_count will be used as a boolean value
3038 	 * after this if/else block.
3039 	 */
3040 	desc_count |= ++tx_ring->packet_stride;
3041 
3042 	/* Algorithm to optimize tail and RS bit setting:
3043 	 * if queue is stopped
3044 	 *	mark RS bit
3045 	 *	reset packet counter
3046 	 * else if xmit_more is supported and is true
3047 	 *	advance packet counter to 4
3048 	 *	reset desc_count to 0
3049 	 *
3050 	 * if desc_count >= 4
3051 	 *	mark RS bit
3052 	 *	reset packet counter
3053 	 * if desc_count > 0
3054 	 *	update tail
3055 	 *
3056 	 * Note: If there are less than 4 descriptors
3057 	 * pending and interrupts were disabled the service task will
3058 	 * trigger a force WB.
3059 	 */
3060 	if (netif_xmit_stopped(txring_txq(tx_ring))) {
3061 		goto do_rs;
3062 	} else if (skb->xmit_more) {
3063 		/* set stride to arm on next packet and reset desc_count */
3064 		tx_ring->packet_stride = WB_STRIDE;
3065 		desc_count = 0;
3066 	} else if (desc_count >= WB_STRIDE) {
3067 do_rs:
3068 		/* write last descriptor with RS bit set */
3069 		td_cmd |= I40E_TX_DESC_CMD_RS;
3070 		tx_ring->packet_stride = 0;
3071 	}
3072 
3073 	tx_desc->cmd_type_offset_bsz =
3074 			build_ctob(td_cmd, td_offset, size, td_tag);
3075 
3076 	/* Force memory writes to complete before letting h/w know there
3077 	 * are new descriptors to fetch.
3078 	 *
3079 	 * We also use this memory barrier to make certain all of the
3080 	 * status bits have been updated before next_to_watch is written.
3081 	 */
3082 	wmb();
3083 
3084 	/* set next_to_watch value indicating a packet is present */
3085 	first->next_to_watch = tx_desc;
3086 
3087 	/* notify HW of packet */
3088 	if (desc_count) {
3089 		writel(i, tx_ring->tail);
3090 
3091 		/* we need this if more than one processor can write to our tail
3092 		 * at a time, it synchronizes IO on IA64/Altix systems
3093 		 */
3094 		mmiowb();
3095 	}
3096 
3097 	return;
3098 
3099 dma_error:
3100 	dev_info(tx_ring->dev, "TX DMA map failed\n");
3101 
3102 	/* clear dma mappings for failed tx_bi map */
3103 	for (;;) {
3104 		tx_bi = &tx_ring->tx_bi[i];
3105 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
3106 		if (tx_bi == first)
3107 			break;
3108 		if (i == 0)
3109 			i = tx_ring->count;
3110 		i--;
3111 	}
3112 
3113 	tx_ring->next_to_use = i;
3114 }
3115 
3116 /**
3117  * i40e_xmit_frame_ring - Sends buffer on Tx ring
3118  * @skb:     send buffer
3119  * @tx_ring: ring to send buffer on
3120  *
3121  * Returns NETDEV_TX_OK if sent, else an error code
3122  **/
3123 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
3124 					struct i40e_ring *tx_ring)
3125 {
3126 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
3127 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
3128 	struct i40e_tx_buffer *first;
3129 	u32 td_offset = 0;
3130 	u32 tx_flags = 0;
3131 	__be16 protocol;
3132 	u32 td_cmd = 0;
3133 	u8 hdr_len = 0;
3134 	int tso, count;
3135 	int tsyn;
3136 
3137 	/* prefetch the data, we'll need it later */
3138 	prefetch(skb->data);
3139 
3140 	i40e_trace(xmit_frame_ring, skb, tx_ring);
3141 
3142 	count = i40e_xmit_descriptor_count(skb);
3143 	if (i40e_chk_linearize(skb, count)) {
3144 		if (__skb_linearize(skb)) {
3145 			dev_kfree_skb_any(skb);
3146 			return NETDEV_TX_OK;
3147 		}
3148 		count = i40e_txd_use_count(skb->len);
3149 		tx_ring->tx_stats.tx_linearize++;
3150 	}
3151 
3152 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
3153 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
3154 	 *       + 4 desc gap to avoid the cache line where head is,
3155 	 *       + 1 desc for context descriptor,
3156 	 * otherwise try next time
3157 	 */
3158 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
3159 		tx_ring->tx_stats.tx_busy++;
3160 		return NETDEV_TX_BUSY;
3161 	}
3162 
3163 	/* record the location of the first descriptor for this packet */
3164 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
3165 	first->skb = skb;
3166 	first->bytecount = skb->len;
3167 	first->gso_segs = 1;
3168 
3169 	/* prepare the xmit flags */
3170 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
3171 		goto out_drop;
3172 
3173 	/* obtain protocol of skb */
3174 	protocol = vlan_get_protocol(skb);
3175 
3176 	/* setup IPv4/IPv6 offloads */
3177 	if (protocol == htons(ETH_P_IP))
3178 		tx_flags |= I40E_TX_FLAGS_IPV4;
3179 	else if (protocol == htons(ETH_P_IPV6))
3180 		tx_flags |= I40E_TX_FLAGS_IPV6;
3181 
3182 	tso = i40e_tso(first, &hdr_len, &cd_type_cmd_tso_mss);
3183 
3184 	if (tso < 0)
3185 		goto out_drop;
3186 	else if (tso)
3187 		tx_flags |= I40E_TX_FLAGS_TSO;
3188 
3189 	/* Always offload the checksum, since it's in the data descriptor */
3190 	tso = i40e_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset,
3191 				  tx_ring, &cd_tunneling);
3192 	if (tso < 0)
3193 		goto out_drop;
3194 
3195 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
3196 
3197 	if (tsyn)
3198 		tx_flags |= I40E_TX_FLAGS_TSYN;
3199 
3200 	skb_tx_timestamp(skb);
3201 
3202 	/* always enable CRC insertion offload */
3203 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
3204 
3205 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
3206 			   cd_tunneling, cd_l2tag2);
3207 
3208 	/* Add Flow Director ATR if it's enabled.
3209 	 *
3210 	 * NOTE: this must always be directly before the data descriptor.
3211 	 */
3212 	i40e_atr(tx_ring, skb, tx_flags);
3213 
3214 	i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
3215 		    td_cmd, td_offset);
3216 
3217 	return NETDEV_TX_OK;
3218 
3219 out_drop:
3220 	i40e_trace(xmit_frame_ring_drop, first->skb, tx_ring);
3221 	dev_kfree_skb_any(first->skb);
3222 	first->skb = NULL;
3223 	return NETDEV_TX_OK;
3224 }
3225 
3226 /**
3227  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
3228  * @skb:    send buffer
3229  * @netdev: network interface device structure
3230  *
3231  * Returns NETDEV_TX_OK if sent, else an error code
3232  **/
3233 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
3234 {
3235 	struct i40e_netdev_priv *np = netdev_priv(netdev);
3236 	struct i40e_vsi *vsi = np->vsi;
3237 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
3238 
3239 	/* hardware can't handle really short frames, hardware padding works
3240 	 * beyond this point
3241 	 */
3242 	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
3243 		return NETDEV_TX_OK;
3244 
3245 	return i40e_xmit_frame_ring(skb, tx_ring);
3246 }
3247