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 <linux/bpf_trace.h>
30 #include "i40e.h"
31 #include "i40e_trace.h"
32 #include "i40e_prototype.h"
33 
34 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
35 				u32 td_tag)
36 {
37 	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
38 			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
39 			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
40 			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
41 			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
42 }
43 
44 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
45 /**
46  * i40e_fdir - Generate a Flow Director descriptor based on fdata
47  * @tx_ring: Tx ring to send buffer on
48  * @fdata: Flow director filter data
49  * @add: Indicate if we are adding a rule or deleting one
50  *
51  **/
52 static void i40e_fdir(struct i40e_ring *tx_ring,
53 		      struct i40e_fdir_filter *fdata, bool add)
54 {
55 	struct i40e_filter_program_desc *fdir_desc;
56 	struct i40e_pf *pf = tx_ring->vsi->back;
57 	u32 flex_ptype, dtype_cmd;
58 	u16 i;
59 
60 	/* grab the next descriptor */
61 	i = tx_ring->next_to_use;
62 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
63 
64 	i++;
65 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
66 
67 	flex_ptype = I40E_TXD_FLTR_QW0_QINDEX_MASK &
68 		     (fdata->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT);
69 
70 	flex_ptype |= I40E_TXD_FLTR_QW0_FLEXOFF_MASK &
71 		      (fdata->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
72 
73 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
74 		      (fdata->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
75 
76 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
77 		      (fdata->flex_offset << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
78 
79 	/* Use LAN VSI Id if not programmed by user */
80 	flex_ptype |= I40E_TXD_FLTR_QW0_DEST_VSI_MASK &
81 		      ((u32)(fdata->dest_vsi ? : pf->vsi[pf->lan_vsi]->id) <<
82 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT);
83 
84 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
85 
86 	dtype_cmd |= add ?
87 		     I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
88 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT :
89 		     I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
90 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT;
91 
92 	dtype_cmd |= I40E_TXD_FLTR_QW1_DEST_MASK &
93 		     (fdata->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT);
94 
95 	dtype_cmd |= I40E_TXD_FLTR_QW1_FD_STATUS_MASK &
96 		     (fdata->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT);
97 
98 	if (fdata->cnt_index) {
99 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
100 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNTINDEX_MASK &
101 			     ((u32)fdata->cnt_index <<
102 			      I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT);
103 	}
104 
105 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
106 	fdir_desc->rsvd = cpu_to_le32(0);
107 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
108 	fdir_desc->fd_id = cpu_to_le32(fdata->fd_id);
109 }
110 
111 #define I40E_FD_CLEAN_DELAY 10
112 /**
113  * i40e_program_fdir_filter - Program a Flow Director filter
114  * @fdir_data: Packet data that will be filter parameters
115  * @raw_packet: the pre-allocated packet buffer for FDir
116  * @pf: The PF pointer
117  * @add: True for add/update, False for remove
118  **/
119 static int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data,
120 				    u8 *raw_packet, struct i40e_pf *pf,
121 				    bool add)
122 {
123 	struct i40e_tx_buffer *tx_buf, *first;
124 	struct i40e_tx_desc *tx_desc;
125 	struct i40e_ring *tx_ring;
126 	struct i40e_vsi *vsi;
127 	struct device *dev;
128 	dma_addr_t dma;
129 	u32 td_cmd = 0;
130 	u16 i;
131 
132 	/* find existing FDIR VSI */
133 	vsi = i40e_find_vsi_by_type(pf, I40E_VSI_FDIR);
134 	if (!vsi)
135 		return -ENOENT;
136 
137 	tx_ring = vsi->tx_rings[0];
138 	dev = tx_ring->dev;
139 
140 	/* we need two descriptors to add/del a filter and we can wait */
141 	for (i = I40E_FD_CLEAN_DELAY; I40E_DESC_UNUSED(tx_ring) < 2; i--) {
142 		if (!i)
143 			return -EAGAIN;
144 		msleep_interruptible(1);
145 	}
146 
147 	dma = dma_map_single(dev, raw_packet,
148 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
149 	if (dma_mapping_error(dev, dma))
150 		goto dma_fail;
151 
152 	/* grab the next descriptor */
153 	i = tx_ring->next_to_use;
154 	first = &tx_ring->tx_bi[i];
155 	i40e_fdir(tx_ring, fdir_data, add);
156 
157 	/* Now program a dummy descriptor */
158 	i = tx_ring->next_to_use;
159 	tx_desc = I40E_TX_DESC(tx_ring, i);
160 	tx_buf = &tx_ring->tx_bi[i];
161 
162 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
163 
164 	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
165 
166 	/* record length, and DMA address */
167 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
168 	dma_unmap_addr_set(tx_buf, dma, dma);
169 
170 	tx_desc->buffer_addr = cpu_to_le64(dma);
171 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
172 
173 	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
174 	tx_buf->raw_buf = (void *)raw_packet;
175 
176 	tx_desc->cmd_type_offset_bsz =
177 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
178 
179 	/* Force memory writes to complete before letting h/w
180 	 * know there are new descriptors to fetch.
181 	 */
182 	wmb();
183 
184 	/* Mark the data descriptor to be watched */
185 	first->next_to_watch = tx_desc;
186 
187 	writel(tx_ring->next_to_use, tx_ring->tail);
188 	return 0;
189 
190 dma_fail:
191 	return -1;
192 }
193 
194 #define IP_HEADER_OFFSET 14
195 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
196 /**
197  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
198  * @vsi: pointer to the targeted VSI
199  * @fd_data: the flow director data required for the FDir descriptor
200  * @add: true adds a filter, false removes it
201  *
202  * Returns 0 if the filters were successfully added or removed
203  **/
204 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
205 				   struct i40e_fdir_filter *fd_data,
206 				   bool add)
207 {
208 	struct i40e_pf *pf = vsi->back;
209 	struct udphdr *udp;
210 	struct iphdr *ip;
211 	u8 *raw_packet;
212 	int ret;
213 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
214 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
215 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
216 
217 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
218 	if (!raw_packet)
219 		return -ENOMEM;
220 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
221 
222 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
223 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
224 	      + sizeof(struct iphdr));
225 
226 	ip->daddr = fd_data->dst_ip;
227 	udp->dest = fd_data->dst_port;
228 	ip->saddr = fd_data->src_ip;
229 	udp->source = fd_data->src_port;
230 
231 	if (fd_data->flex_filter) {
232 		u8 *payload = raw_packet + I40E_UDPIP_DUMMY_PACKET_LEN;
233 		__be16 pattern = fd_data->flex_word;
234 		u16 off = fd_data->flex_offset;
235 
236 		*((__force __be16 *)(payload + off)) = pattern;
237 	}
238 
239 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
240 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
241 	if (ret) {
242 		dev_info(&pf->pdev->dev,
243 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
244 			 fd_data->pctype, fd_data->fd_id, ret);
245 		/* Free the packet buffer since it wasn't added to the ring */
246 		kfree(raw_packet);
247 		return -EOPNOTSUPP;
248 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
249 		if (add)
250 			dev_info(&pf->pdev->dev,
251 				 "Filter OK for PCTYPE %d loc = %d\n",
252 				 fd_data->pctype, fd_data->fd_id);
253 		else
254 			dev_info(&pf->pdev->dev,
255 				 "Filter deleted for PCTYPE %d loc = %d\n",
256 				 fd_data->pctype, fd_data->fd_id);
257 	}
258 
259 	if (add)
260 		pf->fd_udp4_filter_cnt++;
261 	else
262 		pf->fd_udp4_filter_cnt--;
263 
264 	return 0;
265 }
266 
267 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
268 /**
269  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
270  * @vsi: pointer to the targeted VSI
271  * @fd_data: the flow director data required for the FDir descriptor
272  * @add: true adds a filter, false removes it
273  *
274  * Returns 0 if the filters were successfully added or removed
275  **/
276 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
277 				   struct i40e_fdir_filter *fd_data,
278 				   bool add)
279 {
280 	struct i40e_pf *pf = vsi->back;
281 	struct tcphdr *tcp;
282 	struct iphdr *ip;
283 	u8 *raw_packet;
284 	int ret;
285 	/* Dummy packet */
286 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
287 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
288 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
289 		0x0, 0x72, 0, 0, 0, 0};
290 
291 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
292 	if (!raw_packet)
293 		return -ENOMEM;
294 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
295 
296 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
297 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
298 	      + sizeof(struct iphdr));
299 
300 	ip->daddr = fd_data->dst_ip;
301 	tcp->dest = fd_data->dst_port;
302 	ip->saddr = fd_data->src_ip;
303 	tcp->source = fd_data->src_port;
304 
305 	if (fd_data->flex_filter) {
306 		u8 *payload = raw_packet + I40E_TCPIP_DUMMY_PACKET_LEN;
307 		__be16 pattern = fd_data->flex_word;
308 		u16 off = fd_data->flex_offset;
309 
310 		*((__force __be16 *)(payload + off)) = pattern;
311 	}
312 
313 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
314 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
315 	if (ret) {
316 		dev_info(&pf->pdev->dev,
317 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
318 			 fd_data->pctype, fd_data->fd_id, ret);
319 		/* Free the packet buffer since it wasn't added to the ring */
320 		kfree(raw_packet);
321 		return -EOPNOTSUPP;
322 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
323 		if (add)
324 			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
325 				 fd_data->pctype, fd_data->fd_id);
326 		else
327 			dev_info(&pf->pdev->dev,
328 				 "Filter deleted for PCTYPE %d loc = %d\n",
329 				 fd_data->pctype, fd_data->fd_id);
330 	}
331 
332 	if (add) {
333 		pf->fd_tcp4_filter_cnt++;
334 		if ((pf->flags & I40E_FLAG_FD_ATR_ENABLED) &&
335 		    I40E_DEBUG_FD & pf->hw.debug_mask)
336 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
337 		pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
338 	} else {
339 		pf->fd_tcp4_filter_cnt--;
340 	}
341 
342 	return 0;
343 }
344 
345 #define I40E_SCTPIP_DUMMY_PACKET_LEN 46
346 /**
347  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
348  * a specific flow spec
349  * @vsi: pointer to the targeted VSI
350  * @fd_data: the flow director data required for the FDir descriptor
351  * @add: true adds a filter, false removes it
352  *
353  * Returns 0 if the filters were successfully added or removed
354  **/
355 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
356 				    struct i40e_fdir_filter *fd_data,
357 				    bool add)
358 {
359 	struct i40e_pf *pf = vsi->back;
360 	struct sctphdr *sctp;
361 	struct iphdr *ip;
362 	u8 *raw_packet;
363 	int ret;
364 	/* Dummy packet */
365 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
366 		0x45, 0, 0, 0x20, 0, 0, 0x40, 0, 0x40, 0x84, 0, 0, 0, 0, 0, 0,
367 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
368 
369 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
370 	if (!raw_packet)
371 		return -ENOMEM;
372 	memcpy(raw_packet, packet, I40E_SCTPIP_DUMMY_PACKET_LEN);
373 
374 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
375 	sctp = (struct sctphdr *)(raw_packet + IP_HEADER_OFFSET
376 	      + sizeof(struct iphdr));
377 
378 	ip->daddr = fd_data->dst_ip;
379 	sctp->dest = fd_data->dst_port;
380 	ip->saddr = fd_data->src_ip;
381 	sctp->source = fd_data->src_port;
382 
383 	if (fd_data->flex_filter) {
384 		u8 *payload = raw_packet + I40E_SCTPIP_DUMMY_PACKET_LEN;
385 		__be16 pattern = fd_data->flex_word;
386 		u16 off = fd_data->flex_offset;
387 
388 		*((__force __be16 *)(payload + off)) = pattern;
389 	}
390 
391 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_SCTP;
392 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
393 	if (ret) {
394 		dev_info(&pf->pdev->dev,
395 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
396 			 fd_data->pctype, fd_data->fd_id, ret);
397 		/* Free the packet buffer since it wasn't added to the ring */
398 		kfree(raw_packet);
399 		return -EOPNOTSUPP;
400 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
401 		if (add)
402 			dev_info(&pf->pdev->dev,
403 				 "Filter OK for PCTYPE %d loc = %d\n",
404 				 fd_data->pctype, fd_data->fd_id);
405 		else
406 			dev_info(&pf->pdev->dev,
407 				 "Filter deleted for PCTYPE %d loc = %d\n",
408 				 fd_data->pctype, fd_data->fd_id);
409 	}
410 
411 	if (add)
412 		pf->fd_sctp4_filter_cnt++;
413 	else
414 		pf->fd_sctp4_filter_cnt--;
415 
416 	return 0;
417 }
418 
419 #define I40E_IP_DUMMY_PACKET_LEN 34
420 /**
421  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
422  * a specific flow spec
423  * @vsi: pointer to the targeted VSI
424  * @fd_data: the flow director data required for the FDir descriptor
425  * @add: true adds a filter, false removes it
426  *
427  * Returns 0 if the filters were successfully added or removed
428  **/
429 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
430 				  struct i40e_fdir_filter *fd_data,
431 				  bool add)
432 {
433 	struct i40e_pf *pf = vsi->back;
434 	struct iphdr *ip;
435 	u8 *raw_packet;
436 	int ret;
437 	int i;
438 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
439 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
440 		0, 0, 0, 0};
441 
442 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
443 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
444 		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
445 		if (!raw_packet)
446 			return -ENOMEM;
447 		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
448 		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
449 
450 		ip->saddr = fd_data->src_ip;
451 		ip->daddr = fd_data->dst_ip;
452 		ip->protocol = 0;
453 
454 		if (fd_data->flex_filter) {
455 			u8 *payload = raw_packet + I40E_IP_DUMMY_PACKET_LEN;
456 			__be16 pattern = fd_data->flex_word;
457 			u16 off = fd_data->flex_offset;
458 
459 			*((__force __be16 *)(payload + off)) = pattern;
460 		}
461 
462 		fd_data->pctype = i;
463 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
464 		if (ret) {
465 			dev_info(&pf->pdev->dev,
466 				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
467 				 fd_data->pctype, fd_data->fd_id, ret);
468 			/* The packet buffer wasn't added to the ring so we
469 			 * need to free it now.
470 			 */
471 			kfree(raw_packet);
472 			return -EOPNOTSUPP;
473 		} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
474 			if (add)
475 				dev_info(&pf->pdev->dev,
476 					 "Filter OK for PCTYPE %d loc = %d\n",
477 					 fd_data->pctype, fd_data->fd_id);
478 			else
479 				dev_info(&pf->pdev->dev,
480 					 "Filter deleted for PCTYPE %d loc = %d\n",
481 					 fd_data->pctype, fd_data->fd_id);
482 		}
483 	}
484 
485 	if (add)
486 		pf->fd_ip4_filter_cnt++;
487 	else
488 		pf->fd_ip4_filter_cnt--;
489 
490 	return 0;
491 }
492 
493 /**
494  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
495  * @vsi: pointer to the targeted VSI
496  * @cmd: command to get or set RX flow classification rules
497  * @add: true adds a filter, false removes it
498  *
499  **/
500 int i40e_add_del_fdir(struct i40e_vsi *vsi,
501 		      struct i40e_fdir_filter *input, bool add)
502 {
503 	struct i40e_pf *pf = vsi->back;
504 	int ret;
505 
506 	switch (input->flow_type & ~FLOW_EXT) {
507 	case TCP_V4_FLOW:
508 		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
509 		break;
510 	case UDP_V4_FLOW:
511 		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
512 		break;
513 	case SCTP_V4_FLOW:
514 		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
515 		break;
516 	case IP_USER_FLOW:
517 		switch (input->ip4_proto) {
518 		case IPPROTO_TCP:
519 			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
520 			break;
521 		case IPPROTO_UDP:
522 			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
523 			break;
524 		case IPPROTO_SCTP:
525 			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
526 			break;
527 		case IPPROTO_IP:
528 			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
529 			break;
530 		default:
531 			/* We cannot support masking based on protocol */
532 			dev_info(&pf->pdev->dev, "Unsupported IPv4 protocol 0x%02x\n",
533 				 input->ip4_proto);
534 			return -EINVAL;
535 		}
536 		break;
537 	default:
538 		dev_info(&pf->pdev->dev, "Unsupported flow type 0x%02x\n",
539 			 input->flow_type);
540 		return -EINVAL;
541 	}
542 
543 	/* The buffer allocated here will be normally be freed by
544 	 * i40e_clean_fdir_tx_irq() as it reclaims resources after transmit
545 	 * completion. In the event of an error adding the buffer to the FDIR
546 	 * ring, it will immediately be freed. It may also be freed by
547 	 * i40e_clean_tx_ring() when closing the VSI.
548 	 */
549 	return ret;
550 }
551 
552 /**
553  * i40e_fd_handle_status - check the Programming Status for FD
554  * @rx_ring: the Rx ring for this descriptor
555  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
556  * @prog_id: the id originally used for programming
557  *
558  * This is used to verify if the FD programming or invalidation
559  * requested by SW to the HW is successful or not and take actions accordingly.
560  **/
561 static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
562 				  union i40e_rx_desc *rx_desc, u8 prog_id)
563 {
564 	struct i40e_pf *pf = rx_ring->vsi->back;
565 	struct pci_dev *pdev = pf->pdev;
566 	u32 fcnt_prog, fcnt_avail;
567 	u32 error;
568 	u64 qw;
569 
570 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
571 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
572 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
573 
574 	if (error == BIT(I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
575 		pf->fd_inv = le32_to_cpu(rx_desc->wb.qword0.hi_dword.fd_id);
576 		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
577 		    (I40E_DEBUG_FD & pf->hw.debug_mask))
578 			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
579 				 pf->fd_inv);
580 
581 		/* Check if the programming error is for ATR.
582 		 * If so, auto disable ATR and set a state for
583 		 * flush in progress. Next time we come here if flush is in
584 		 * progress do nothing, once flush is complete the state will
585 		 * be cleared.
586 		 */
587 		if (test_bit(__I40E_FD_FLUSH_REQUESTED, pf->state))
588 			return;
589 
590 		pf->fd_add_err++;
591 		/* store the current atr filter count */
592 		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
593 
594 		if ((rx_desc->wb.qword0.hi_dword.fd_id == 0) &&
595 		    pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED) {
596 			pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
597 			set_bit(__I40E_FD_FLUSH_REQUESTED, pf->state);
598 		}
599 
600 		/* filter programming failed most likely due to table full */
601 		fcnt_prog = i40e_get_global_fd_count(pf);
602 		fcnt_avail = pf->fdir_pf_filter_count;
603 		/* If ATR is running fcnt_prog can quickly change,
604 		 * if we are very close to full, it makes sense to disable
605 		 * FD ATR/SB and then re-enable it when there is room.
606 		 */
607 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
608 			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
609 			    !(pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED)) {
610 				pf->flags |= I40E_FLAG_FD_SB_AUTO_DISABLED;
611 				if (I40E_DEBUG_FD & pf->hw.debug_mask)
612 					dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
613 			}
614 		}
615 	} else if (error == BIT(I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
616 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
617 			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
618 				 rx_desc->wb.qword0.hi_dword.fd_id);
619 	}
620 }
621 
622 /**
623  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
624  * @ring:      the ring that owns the buffer
625  * @tx_buffer: the buffer to free
626  **/
627 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
628 					    struct i40e_tx_buffer *tx_buffer)
629 {
630 	if (tx_buffer->skb) {
631 		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
632 			kfree(tx_buffer->raw_buf);
633 		else if (ring_is_xdp(ring))
634 			page_frag_free(tx_buffer->raw_buf);
635 		else
636 			dev_kfree_skb_any(tx_buffer->skb);
637 		if (dma_unmap_len(tx_buffer, len))
638 			dma_unmap_single(ring->dev,
639 					 dma_unmap_addr(tx_buffer, dma),
640 					 dma_unmap_len(tx_buffer, len),
641 					 DMA_TO_DEVICE);
642 	} else if (dma_unmap_len(tx_buffer, len)) {
643 		dma_unmap_page(ring->dev,
644 			       dma_unmap_addr(tx_buffer, dma),
645 			       dma_unmap_len(tx_buffer, len),
646 			       DMA_TO_DEVICE);
647 	}
648 
649 	tx_buffer->next_to_watch = NULL;
650 	tx_buffer->skb = NULL;
651 	dma_unmap_len_set(tx_buffer, len, 0);
652 	/* tx_buffer must be completely set up in the transmit path */
653 }
654 
655 /**
656  * i40e_clean_tx_ring - Free any empty Tx buffers
657  * @tx_ring: ring to be cleaned
658  **/
659 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
660 {
661 	unsigned long bi_size;
662 	u16 i;
663 
664 	/* ring already cleared, nothing to do */
665 	if (!tx_ring->tx_bi)
666 		return;
667 
668 	/* Free all the Tx ring sk_buffs */
669 	for (i = 0; i < tx_ring->count; i++)
670 		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
671 
672 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
673 	memset(tx_ring->tx_bi, 0, bi_size);
674 
675 	/* Zero out the descriptor ring */
676 	memset(tx_ring->desc, 0, tx_ring->size);
677 
678 	tx_ring->next_to_use = 0;
679 	tx_ring->next_to_clean = 0;
680 
681 	if (!tx_ring->netdev)
682 		return;
683 
684 	/* cleanup Tx queue statistics */
685 	netdev_tx_reset_queue(txring_txq(tx_ring));
686 }
687 
688 /**
689  * i40e_free_tx_resources - Free Tx resources per queue
690  * @tx_ring: Tx descriptor ring for a specific queue
691  *
692  * Free all transmit software resources
693  **/
694 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
695 {
696 	i40e_clean_tx_ring(tx_ring);
697 	kfree(tx_ring->tx_bi);
698 	tx_ring->tx_bi = NULL;
699 
700 	if (tx_ring->desc) {
701 		dma_free_coherent(tx_ring->dev, tx_ring->size,
702 				  tx_ring->desc, tx_ring->dma);
703 		tx_ring->desc = NULL;
704 	}
705 }
706 
707 /**
708  * i40e_get_tx_pending - how many tx descriptors not processed
709  * @tx_ring: the ring of descriptors
710  *
711  * Since there is no access to the ring head register
712  * in XL710, we need to use our local copies
713  **/
714 u32 i40e_get_tx_pending(struct i40e_ring *ring)
715 {
716 	u32 head, tail;
717 
718 	head = i40e_get_head(ring);
719 	tail = readl(ring->tail);
720 
721 	if (head != tail)
722 		return (head < tail) ?
723 			tail - head : (tail + ring->count - head);
724 
725 	return 0;
726 }
727 
728 #define WB_STRIDE 4
729 
730 /**
731  * i40e_clean_tx_irq - Reclaim resources after transmit completes
732  * @vsi: the VSI we care about
733  * @tx_ring: Tx ring to clean
734  * @napi_budget: Used to determine if we are in netpoll
735  *
736  * Returns true if there's any budget left (e.g. the clean is finished)
737  **/
738 static bool i40e_clean_tx_irq(struct i40e_vsi *vsi,
739 			      struct i40e_ring *tx_ring, int napi_budget)
740 {
741 	u16 i = tx_ring->next_to_clean;
742 	struct i40e_tx_buffer *tx_buf;
743 	struct i40e_tx_desc *tx_head;
744 	struct i40e_tx_desc *tx_desc;
745 	unsigned int total_bytes = 0, total_packets = 0;
746 	unsigned int budget = vsi->work_limit;
747 
748 	tx_buf = &tx_ring->tx_bi[i];
749 	tx_desc = I40E_TX_DESC(tx_ring, i);
750 	i -= tx_ring->count;
751 
752 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
753 
754 	do {
755 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
756 
757 		/* if next_to_watch is not set then there is no work pending */
758 		if (!eop_desc)
759 			break;
760 
761 		/* prevent any other reads prior to eop_desc */
762 		read_barrier_depends();
763 
764 		i40e_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
765 		/* we have caught up to head, no work left to do */
766 		if (tx_head == tx_desc)
767 			break;
768 
769 		/* clear next_to_watch to prevent false hangs */
770 		tx_buf->next_to_watch = NULL;
771 
772 		/* update the statistics for this packet */
773 		total_bytes += tx_buf->bytecount;
774 		total_packets += tx_buf->gso_segs;
775 
776 		/* free the skb/XDP data */
777 		if (ring_is_xdp(tx_ring))
778 			page_frag_free(tx_buf->raw_buf);
779 		else
780 			napi_consume_skb(tx_buf->skb, napi_budget);
781 
782 		/* unmap skb header data */
783 		dma_unmap_single(tx_ring->dev,
784 				 dma_unmap_addr(tx_buf, dma),
785 				 dma_unmap_len(tx_buf, len),
786 				 DMA_TO_DEVICE);
787 
788 		/* clear tx_buffer data */
789 		tx_buf->skb = NULL;
790 		dma_unmap_len_set(tx_buf, len, 0);
791 
792 		/* unmap remaining buffers */
793 		while (tx_desc != eop_desc) {
794 			i40e_trace(clean_tx_irq_unmap,
795 				   tx_ring, tx_desc, tx_buf);
796 
797 			tx_buf++;
798 			tx_desc++;
799 			i++;
800 			if (unlikely(!i)) {
801 				i -= tx_ring->count;
802 				tx_buf = tx_ring->tx_bi;
803 				tx_desc = I40E_TX_DESC(tx_ring, 0);
804 			}
805 
806 			/* unmap any remaining paged data */
807 			if (dma_unmap_len(tx_buf, len)) {
808 				dma_unmap_page(tx_ring->dev,
809 					       dma_unmap_addr(tx_buf, dma),
810 					       dma_unmap_len(tx_buf, len),
811 					       DMA_TO_DEVICE);
812 				dma_unmap_len_set(tx_buf, len, 0);
813 			}
814 		}
815 
816 		/* move us one more past the eop_desc for start of next pkt */
817 		tx_buf++;
818 		tx_desc++;
819 		i++;
820 		if (unlikely(!i)) {
821 			i -= tx_ring->count;
822 			tx_buf = tx_ring->tx_bi;
823 			tx_desc = I40E_TX_DESC(tx_ring, 0);
824 		}
825 
826 		prefetch(tx_desc);
827 
828 		/* update budget accounting */
829 		budget--;
830 	} while (likely(budget));
831 
832 	i += tx_ring->count;
833 	tx_ring->next_to_clean = i;
834 	u64_stats_update_begin(&tx_ring->syncp);
835 	tx_ring->stats.bytes += total_bytes;
836 	tx_ring->stats.packets += total_packets;
837 	u64_stats_update_end(&tx_ring->syncp);
838 	tx_ring->q_vector->tx.total_bytes += total_bytes;
839 	tx_ring->q_vector->tx.total_packets += total_packets;
840 
841 	if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
842 		/* check to see if there are < 4 descriptors
843 		 * waiting to be written back, then kick the hardware to force
844 		 * them to be written back in case we stay in NAPI.
845 		 * In this mode on X722 we do not enable Interrupt.
846 		 */
847 		unsigned int j = i40e_get_tx_pending(tx_ring);
848 
849 		if (budget &&
850 		    ((j / WB_STRIDE) == 0) && (j > 0) &&
851 		    !test_bit(__I40E_VSI_DOWN, vsi->state) &&
852 		    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
853 			tx_ring->arm_wb = true;
854 	}
855 
856 	if (ring_is_xdp(tx_ring))
857 		return !!budget;
858 
859 	/* notify netdev of completed buffers */
860 	netdev_tx_completed_queue(txring_txq(tx_ring),
861 				  total_packets, total_bytes);
862 
863 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
864 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
865 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
866 		/* Make sure that anybody stopping the queue after this
867 		 * sees the new next_to_clean.
868 		 */
869 		smp_mb();
870 		if (__netif_subqueue_stopped(tx_ring->netdev,
871 					     tx_ring->queue_index) &&
872 		   !test_bit(__I40E_VSI_DOWN, vsi->state)) {
873 			netif_wake_subqueue(tx_ring->netdev,
874 					    tx_ring->queue_index);
875 			++tx_ring->tx_stats.restart_queue;
876 		}
877 	}
878 
879 	return !!budget;
880 }
881 
882 /**
883  * i40e_enable_wb_on_itr - Arm hardware to do a wb, interrupts are not enabled
884  * @vsi: the VSI we care about
885  * @q_vector: the vector on which to enable writeback
886  *
887  **/
888 static void i40e_enable_wb_on_itr(struct i40e_vsi *vsi,
889 				  struct i40e_q_vector *q_vector)
890 {
891 	u16 flags = q_vector->tx.ring[0].flags;
892 	u32 val;
893 
894 	if (!(flags & I40E_TXR_FLAGS_WB_ON_ITR))
895 		return;
896 
897 	if (q_vector->arm_wb_state)
898 		return;
899 
900 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
901 		val = I40E_PFINT_DYN_CTLN_WB_ON_ITR_MASK |
902 		      I40E_PFINT_DYN_CTLN_ITR_INDX_MASK; /* set noitr */
903 
904 		wr32(&vsi->back->hw,
905 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx + vsi->base_vector - 1),
906 		     val);
907 	} else {
908 		val = I40E_PFINT_DYN_CTL0_WB_ON_ITR_MASK |
909 		      I40E_PFINT_DYN_CTL0_ITR_INDX_MASK; /* set noitr */
910 
911 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
912 	}
913 	q_vector->arm_wb_state = true;
914 }
915 
916 /**
917  * i40e_force_wb - Issue SW Interrupt so HW does a wb
918  * @vsi: the VSI we care about
919  * @q_vector: the vector  on which to force writeback
920  *
921  **/
922 void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
923 {
924 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
925 		u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
926 			  I40E_PFINT_DYN_CTLN_ITR_INDX_MASK | /* set noitr */
927 			  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
928 			  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
929 			  /* allow 00 to be written to the index */
930 
931 		wr32(&vsi->back->hw,
932 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx +
933 					 vsi->base_vector - 1), val);
934 	} else {
935 		u32 val = I40E_PFINT_DYN_CTL0_INTENA_MASK |
936 			  I40E_PFINT_DYN_CTL0_ITR_INDX_MASK | /* set noitr */
937 			  I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK |
938 			  I40E_PFINT_DYN_CTL0_SW_ITR_INDX_ENA_MASK;
939 			/* allow 00 to be written to the index */
940 
941 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
942 	}
943 }
944 
945 /**
946  * i40e_set_new_dynamic_itr - Find new ITR level
947  * @rc: structure containing ring performance data
948  *
949  * Returns true if ITR changed, false if not
950  *
951  * Stores a new ITR value based on packets and byte counts during
952  * the last interrupt.  The advantage of per interrupt computation
953  * is faster updates and more accurate ITR for the current traffic
954  * pattern.  Constants in this function were computed based on
955  * theoretical maximum wire speed and thresholds were set based on
956  * testing data as well as attempting to minimize response time
957  * while increasing bulk throughput.
958  **/
959 static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
960 {
961 	enum i40e_latency_range new_latency_range = rc->latency_range;
962 	struct i40e_q_vector *qv = rc->ring->q_vector;
963 	u32 new_itr = rc->itr;
964 	int bytes_per_int;
965 	int usecs;
966 
967 	if (rc->total_packets == 0 || !rc->itr)
968 		return false;
969 
970 	/* simple throttlerate management
971 	 *   0-10MB/s   lowest (50000 ints/s)
972 	 *  10-20MB/s   low    (20000 ints/s)
973 	 *  20-1249MB/s bulk   (18000 ints/s)
974 	 *  > 40000 Rx packets per second (8000 ints/s)
975 	 *
976 	 * The math works out because the divisor is in 10^(-6) which
977 	 * turns the bytes/us input value into MB/s values, but
978 	 * make sure to use usecs, as the register values written
979 	 * are in 2 usec increments in the ITR registers, and make sure
980 	 * to use the smoothed values that the countdown timer gives us.
981 	 */
982 	usecs = (rc->itr << 1) * ITR_COUNTDOWN_START;
983 	bytes_per_int = rc->total_bytes / usecs;
984 
985 	switch (new_latency_range) {
986 	case I40E_LOWEST_LATENCY:
987 		if (bytes_per_int > 10)
988 			new_latency_range = I40E_LOW_LATENCY;
989 		break;
990 	case I40E_LOW_LATENCY:
991 		if (bytes_per_int > 20)
992 			new_latency_range = I40E_BULK_LATENCY;
993 		else if (bytes_per_int <= 10)
994 			new_latency_range = I40E_LOWEST_LATENCY;
995 		break;
996 	case I40E_BULK_LATENCY:
997 	case I40E_ULTRA_LATENCY:
998 	default:
999 		if (bytes_per_int <= 20)
1000 			new_latency_range = I40E_LOW_LATENCY;
1001 		break;
1002 	}
1003 
1004 	/* this is to adjust RX more aggressively when streaming small
1005 	 * packets.  The value of 40000 was picked as it is just beyond
1006 	 * what the hardware can receive per second if in low latency
1007 	 * mode.
1008 	 */
1009 #define RX_ULTRA_PACKET_RATE 40000
1010 
1011 	if ((((rc->total_packets * 1000000) / usecs) > RX_ULTRA_PACKET_RATE) &&
1012 	    (&qv->rx == rc))
1013 		new_latency_range = I40E_ULTRA_LATENCY;
1014 
1015 	rc->latency_range = new_latency_range;
1016 
1017 	switch (new_latency_range) {
1018 	case I40E_LOWEST_LATENCY:
1019 		new_itr = I40E_ITR_50K;
1020 		break;
1021 	case I40E_LOW_LATENCY:
1022 		new_itr = I40E_ITR_20K;
1023 		break;
1024 	case I40E_BULK_LATENCY:
1025 		new_itr = I40E_ITR_18K;
1026 		break;
1027 	case I40E_ULTRA_LATENCY:
1028 		new_itr = I40E_ITR_8K;
1029 		break;
1030 	default:
1031 		break;
1032 	}
1033 
1034 	rc->total_bytes = 0;
1035 	rc->total_packets = 0;
1036 
1037 	if (new_itr != rc->itr) {
1038 		rc->itr = new_itr;
1039 		return true;
1040 	}
1041 
1042 	return false;
1043 }
1044 
1045 /**
1046  * i40e_rx_is_programming_status - check for programming status descriptor
1047  * @qw: qword representing status_error_len in CPU ordering
1048  *
1049  * The value of in the descriptor length field indicate if this
1050  * is a programming status descriptor for flow director or FCoE
1051  * by the value of I40E_RX_PROG_STATUS_DESC_LENGTH, otherwise
1052  * it is a packet descriptor.
1053  **/
1054 static inline bool i40e_rx_is_programming_status(u64 qw)
1055 {
1056 	/* The Rx filter programming status and SPH bit occupy the same
1057 	 * spot in the descriptor. Since we don't support packet split we
1058 	 * can just reuse the bit as an indication that this is a
1059 	 * programming status descriptor.
1060 	 */
1061 	return qw & I40E_RXD_QW1_LENGTH_SPH_MASK;
1062 }
1063 
1064 /**
1065  * i40e_clean_programming_status - clean the programming status descriptor
1066  * @rx_ring: the rx ring that has this descriptor
1067  * @rx_desc: the rx descriptor written back by HW
1068  * @qw: qword representing status_error_len in CPU ordering
1069  *
1070  * Flow director should handle FD_FILTER_STATUS to check its filter programming
1071  * status being successful or not and take actions accordingly. FCoE should
1072  * handle its context/filter programming/invalidation status and take actions.
1073  *
1074  **/
1075 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
1076 					  union i40e_rx_desc *rx_desc,
1077 					  u64 qw)
1078 {
1079 	u32 ntc = rx_ring->next_to_clean + 1;
1080 	u8 id;
1081 
1082 	/* fetch, update, and store next to clean */
1083 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1084 	rx_ring->next_to_clean = ntc;
1085 
1086 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1087 
1088 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
1089 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
1090 
1091 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
1092 		i40e_fd_handle_status(rx_ring, rx_desc, id);
1093 }
1094 
1095 /**
1096  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
1097  * @tx_ring: the tx ring to set up
1098  *
1099  * Return 0 on success, negative on error
1100  **/
1101 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
1102 {
1103 	struct device *dev = tx_ring->dev;
1104 	int bi_size;
1105 
1106 	if (!dev)
1107 		return -ENOMEM;
1108 
1109 	/* warn if we are about to overwrite the pointer */
1110 	WARN_ON(tx_ring->tx_bi);
1111 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
1112 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
1113 	if (!tx_ring->tx_bi)
1114 		goto err;
1115 
1116 	/* round up to nearest 4K */
1117 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
1118 	/* add u32 for head writeback, align after this takes care of
1119 	 * guaranteeing this is at least one cache line in size
1120 	 */
1121 	tx_ring->size += sizeof(u32);
1122 	tx_ring->size = ALIGN(tx_ring->size, 4096);
1123 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
1124 					   &tx_ring->dma, GFP_KERNEL);
1125 	if (!tx_ring->desc) {
1126 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
1127 			 tx_ring->size);
1128 		goto err;
1129 	}
1130 
1131 	tx_ring->next_to_use = 0;
1132 	tx_ring->next_to_clean = 0;
1133 	return 0;
1134 
1135 err:
1136 	kfree(tx_ring->tx_bi);
1137 	tx_ring->tx_bi = NULL;
1138 	return -ENOMEM;
1139 }
1140 
1141 /**
1142  * i40e_clean_rx_ring - Free Rx buffers
1143  * @rx_ring: ring to be cleaned
1144  **/
1145 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1146 {
1147 	unsigned long bi_size;
1148 	u16 i;
1149 
1150 	/* ring already cleared, nothing to do */
1151 	if (!rx_ring->rx_bi)
1152 		return;
1153 
1154 	if (rx_ring->skb) {
1155 		dev_kfree_skb(rx_ring->skb);
1156 		rx_ring->skb = NULL;
1157 	}
1158 
1159 	/* Free all the Rx ring sk_buffs */
1160 	for (i = 0; i < rx_ring->count; i++) {
1161 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
1162 
1163 		if (!rx_bi->page)
1164 			continue;
1165 
1166 		/* Invalidate cache lines that may have been written to by
1167 		 * device so that we avoid corrupting memory.
1168 		 */
1169 		dma_sync_single_range_for_cpu(rx_ring->dev,
1170 					      rx_bi->dma,
1171 					      rx_bi->page_offset,
1172 					      rx_ring->rx_buf_len,
1173 					      DMA_FROM_DEVICE);
1174 
1175 		/* free resources associated with mapping */
1176 		dma_unmap_page_attrs(rx_ring->dev, rx_bi->dma,
1177 				     i40e_rx_pg_size(rx_ring),
1178 				     DMA_FROM_DEVICE,
1179 				     I40E_RX_DMA_ATTR);
1180 
1181 		__page_frag_cache_drain(rx_bi->page, rx_bi->pagecnt_bias);
1182 
1183 		rx_bi->page = NULL;
1184 		rx_bi->page_offset = 0;
1185 	}
1186 
1187 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1188 	memset(rx_ring->rx_bi, 0, bi_size);
1189 
1190 	/* Zero out the descriptor ring */
1191 	memset(rx_ring->desc, 0, rx_ring->size);
1192 
1193 	rx_ring->next_to_alloc = 0;
1194 	rx_ring->next_to_clean = 0;
1195 	rx_ring->next_to_use = 0;
1196 }
1197 
1198 /**
1199  * i40e_free_rx_resources - Free Rx resources
1200  * @rx_ring: ring to clean the resources from
1201  *
1202  * Free all receive software resources
1203  **/
1204 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1205 {
1206 	i40e_clean_rx_ring(rx_ring);
1207 	rx_ring->xdp_prog = NULL;
1208 	kfree(rx_ring->rx_bi);
1209 	rx_ring->rx_bi = NULL;
1210 
1211 	if (rx_ring->desc) {
1212 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1213 				  rx_ring->desc, rx_ring->dma);
1214 		rx_ring->desc = NULL;
1215 	}
1216 }
1217 
1218 /**
1219  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1220  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1221  *
1222  * Returns 0 on success, negative on failure
1223  **/
1224 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1225 {
1226 	struct device *dev = rx_ring->dev;
1227 	int bi_size;
1228 
1229 	/* warn if we are about to overwrite the pointer */
1230 	WARN_ON(rx_ring->rx_bi);
1231 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1232 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1233 	if (!rx_ring->rx_bi)
1234 		goto err;
1235 
1236 	u64_stats_init(&rx_ring->syncp);
1237 
1238 	/* Round up to nearest 4K */
1239 	rx_ring->size = rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1240 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1241 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1242 					   &rx_ring->dma, GFP_KERNEL);
1243 
1244 	if (!rx_ring->desc) {
1245 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1246 			 rx_ring->size);
1247 		goto err;
1248 	}
1249 
1250 	rx_ring->next_to_alloc = 0;
1251 	rx_ring->next_to_clean = 0;
1252 	rx_ring->next_to_use = 0;
1253 
1254 	rx_ring->xdp_prog = rx_ring->vsi->xdp_prog;
1255 
1256 	return 0;
1257 err:
1258 	kfree(rx_ring->rx_bi);
1259 	rx_ring->rx_bi = NULL;
1260 	return -ENOMEM;
1261 }
1262 
1263 /**
1264  * i40e_release_rx_desc - Store the new tail and head values
1265  * @rx_ring: ring to bump
1266  * @val: new head index
1267  **/
1268 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1269 {
1270 	rx_ring->next_to_use = val;
1271 
1272 	/* update next to alloc since we have filled the ring */
1273 	rx_ring->next_to_alloc = val;
1274 
1275 	/* Force memory writes to complete before letting h/w
1276 	 * know there are new descriptors to fetch.  (Only
1277 	 * applicable for weak-ordered memory model archs,
1278 	 * such as IA-64).
1279 	 */
1280 	wmb();
1281 	writel(val, rx_ring->tail);
1282 }
1283 
1284 /**
1285  * i40e_rx_offset - Return expected offset into page to access data
1286  * @rx_ring: Ring we are requesting offset of
1287  *
1288  * Returns the offset value for ring into the data buffer.
1289  */
1290 static inline unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
1291 {
1292 	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
1293 }
1294 
1295 /**
1296  * i40e_alloc_mapped_page - recycle or make a new page
1297  * @rx_ring: ring to use
1298  * @bi: rx_buffer struct to modify
1299  *
1300  * Returns true if the page was successfully allocated or
1301  * reused.
1302  **/
1303 static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
1304 				   struct i40e_rx_buffer *bi)
1305 {
1306 	struct page *page = bi->page;
1307 	dma_addr_t dma;
1308 
1309 	/* since we are recycling buffers we should seldom need to alloc */
1310 	if (likely(page)) {
1311 		rx_ring->rx_stats.page_reuse_count++;
1312 		return true;
1313 	}
1314 
1315 	/* alloc new page for storage */
1316 	page = dev_alloc_pages(i40e_rx_pg_order(rx_ring));
1317 	if (unlikely(!page)) {
1318 		rx_ring->rx_stats.alloc_page_failed++;
1319 		return false;
1320 	}
1321 
1322 	/* map page for use */
1323 	dma = dma_map_page_attrs(rx_ring->dev, page, 0,
1324 				 i40e_rx_pg_size(rx_ring),
1325 				 DMA_FROM_DEVICE,
1326 				 I40E_RX_DMA_ATTR);
1327 
1328 	/* if mapping failed free memory back to system since
1329 	 * there isn't much point in holding memory we can't use
1330 	 */
1331 	if (dma_mapping_error(rx_ring->dev, dma)) {
1332 		__free_pages(page, i40e_rx_pg_order(rx_ring));
1333 		rx_ring->rx_stats.alloc_page_failed++;
1334 		return false;
1335 	}
1336 
1337 	bi->dma = dma;
1338 	bi->page = page;
1339 	bi->page_offset = i40e_rx_offset(rx_ring);
1340 
1341 	/* initialize pagecnt_bias to 1 representing we fully own page */
1342 	bi->pagecnt_bias = 1;
1343 
1344 	return true;
1345 }
1346 
1347 /**
1348  * i40e_receive_skb - Send a completed packet up the stack
1349  * @rx_ring:  rx ring in play
1350  * @skb: packet to send up
1351  * @vlan_tag: vlan tag for packet
1352  **/
1353 static void i40e_receive_skb(struct i40e_ring *rx_ring,
1354 			     struct sk_buff *skb, u16 vlan_tag)
1355 {
1356 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1357 
1358 	if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
1359 	    (vlan_tag & VLAN_VID_MASK))
1360 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1361 
1362 	napi_gro_receive(&q_vector->napi, skb);
1363 }
1364 
1365 /**
1366  * i40e_alloc_rx_buffers - Replace used receive buffers
1367  * @rx_ring: ring to place buffers on
1368  * @cleaned_count: number of buffers to replace
1369  *
1370  * Returns false if all allocations were successful, true if any fail
1371  **/
1372 bool i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1373 {
1374 	u16 ntu = rx_ring->next_to_use;
1375 	union i40e_rx_desc *rx_desc;
1376 	struct i40e_rx_buffer *bi;
1377 
1378 	/* do nothing if no valid netdev defined */
1379 	if (!rx_ring->netdev || !cleaned_count)
1380 		return false;
1381 
1382 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
1383 	bi = &rx_ring->rx_bi[ntu];
1384 
1385 	do {
1386 		if (!i40e_alloc_mapped_page(rx_ring, bi))
1387 			goto no_buffers;
1388 
1389 		/* sync the buffer for use by the device */
1390 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
1391 						 bi->page_offset,
1392 						 rx_ring->rx_buf_len,
1393 						 DMA_FROM_DEVICE);
1394 
1395 		/* Refresh the desc even if buffer_addrs didn't change
1396 		 * because each write-back erases this info.
1397 		 */
1398 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
1399 
1400 		rx_desc++;
1401 		bi++;
1402 		ntu++;
1403 		if (unlikely(ntu == rx_ring->count)) {
1404 			rx_desc = I40E_RX_DESC(rx_ring, 0);
1405 			bi = rx_ring->rx_bi;
1406 			ntu = 0;
1407 		}
1408 
1409 		/* clear the status bits for the next_to_use descriptor */
1410 		rx_desc->wb.qword1.status_error_len = 0;
1411 
1412 		cleaned_count--;
1413 	} while (cleaned_count);
1414 
1415 	if (rx_ring->next_to_use != ntu)
1416 		i40e_release_rx_desc(rx_ring, ntu);
1417 
1418 	return false;
1419 
1420 no_buffers:
1421 	if (rx_ring->next_to_use != ntu)
1422 		i40e_release_rx_desc(rx_ring, ntu);
1423 
1424 	/* make sure to come back via polling to try again after
1425 	 * allocation failure
1426 	 */
1427 	return true;
1428 }
1429 
1430 /**
1431  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1432  * @vsi: the VSI we care about
1433  * @skb: skb currently being received and modified
1434  * @rx_desc: the receive descriptor
1435  **/
1436 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1437 				    struct sk_buff *skb,
1438 				    union i40e_rx_desc *rx_desc)
1439 {
1440 	struct i40e_rx_ptype_decoded decoded;
1441 	u32 rx_error, rx_status;
1442 	bool ipv4, ipv6;
1443 	u8 ptype;
1444 	u64 qword;
1445 
1446 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1447 	ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >> I40E_RXD_QW1_PTYPE_SHIFT;
1448 	rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1449 		   I40E_RXD_QW1_ERROR_SHIFT;
1450 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1451 		    I40E_RXD_QW1_STATUS_SHIFT;
1452 	decoded = decode_rx_desc_ptype(ptype);
1453 
1454 	skb->ip_summed = CHECKSUM_NONE;
1455 
1456 	skb_checksum_none_assert(skb);
1457 
1458 	/* Rx csum enabled and ip headers found? */
1459 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1460 		return;
1461 
1462 	/* did the hardware decode the packet and checksum? */
1463 	if (!(rx_status & BIT(I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1464 		return;
1465 
1466 	/* both known and outer_ip must be set for the below code to work */
1467 	if (!(decoded.known && decoded.outer_ip))
1468 		return;
1469 
1470 	ipv4 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1471 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4);
1472 	ipv6 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1473 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6);
1474 
1475 	if (ipv4 &&
1476 	    (rx_error & (BIT(I40E_RX_DESC_ERROR_IPE_SHIFT) |
1477 			 BIT(I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1478 		goto checksum_fail;
1479 
1480 	/* likely incorrect csum if alternate IP extension headers found */
1481 	if (ipv6 &&
1482 	    rx_status & BIT(I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1483 		/* don't increment checksum err here, non-fatal err */
1484 		return;
1485 
1486 	/* there was some L4 error, count error and punt packet to the stack */
1487 	if (rx_error & BIT(I40E_RX_DESC_ERROR_L4E_SHIFT))
1488 		goto checksum_fail;
1489 
1490 	/* handle packets that were not able to be checksummed due
1491 	 * to arrival speed, in this case the stack can compute
1492 	 * the csum.
1493 	 */
1494 	if (rx_error & BIT(I40E_RX_DESC_ERROR_PPRS_SHIFT))
1495 		return;
1496 
1497 	/* If there is an outer header present that might contain a checksum
1498 	 * we need to bump the checksum level by 1 to reflect the fact that
1499 	 * we are indicating we validated the inner checksum.
1500 	 */
1501 	if (decoded.tunnel_type >= I40E_RX_PTYPE_TUNNEL_IP_GRENAT)
1502 		skb->csum_level = 1;
1503 
1504 	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
1505 	switch (decoded.inner_prot) {
1506 	case I40E_RX_PTYPE_INNER_PROT_TCP:
1507 	case I40E_RX_PTYPE_INNER_PROT_UDP:
1508 	case I40E_RX_PTYPE_INNER_PROT_SCTP:
1509 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1510 		/* fall though */
1511 	default:
1512 		break;
1513 	}
1514 
1515 	return;
1516 
1517 checksum_fail:
1518 	vsi->back->hw_csum_rx_error++;
1519 }
1520 
1521 /**
1522  * i40e_ptype_to_htype - get a hash type
1523  * @ptype: the ptype value from the descriptor
1524  *
1525  * Returns a hash type to be used by skb_set_hash
1526  **/
1527 static inline int i40e_ptype_to_htype(u8 ptype)
1528 {
1529 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1530 
1531 	if (!decoded.known)
1532 		return PKT_HASH_TYPE_NONE;
1533 
1534 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1535 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1536 		return PKT_HASH_TYPE_L4;
1537 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1538 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1539 		return PKT_HASH_TYPE_L3;
1540 	else
1541 		return PKT_HASH_TYPE_L2;
1542 }
1543 
1544 /**
1545  * i40e_rx_hash - set the hash value in the skb
1546  * @ring: descriptor ring
1547  * @rx_desc: specific descriptor
1548  **/
1549 static inline void i40e_rx_hash(struct i40e_ring *ring,
1550 				union i40e_rx_desc *rx_desc,
1551 				struct sk_buff *skb,
1552 				u8 rx_ptype)
1553 {
1554 	u32 hash;
1555 	const __le64 rss_mask =
1556 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1557 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1558 
1559 	if (!(ring->netdev->features & NETIF_F_RXHASH))
1560 		return;
1561 
1562 	if ((rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask) {
1563 		hash = le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1564 		skb_set_hash(skb, hash, i40e_ptype_to_htype(rx_ptype));
1565 	}
1566 }
1567 
1568 /**
1569  * i40e_process_skb_fields - Populate skb header fields from Rx descriptor
1570  * @rx_ring: rx descriptor ring packet is being transacted on
1571  * @rx_desc: pointer to the EOP Rx descriptor
1572  * @skb: pointer to current skb being populated
1573  * @rx_ptype: the packet type decoded by hardware
1574  *
1575  * This function checks the ring, descriptor, and packet information in
1576  * order to populate the hash, checksum, VLAN, protocol, and
1577  * other fields within the skb.
1578  **/
1579 static inline
1580 void i40e_process_skb_fields(struct i40e_ring *rx_ring,
1581 			     union i40e_rx_desc *rx_desc, struct sk_buff *skb,
1582 			     u8 rx_ptype)
1583 {
1584 	u64 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1585 	u32 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1586 			I40E_RXD_QW1_STATUS_SHIFT;
1587 	u32 tsynvalid = rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK;
1588 	u32 tsyn = (rx_status & I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1589 		   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT;
1590 
1591 	if (unlikely(tsynvalid))
1592 		i40e_ptp_rx_hwtstamp(rx_ring->vsi->back, skb, tsyn);
1593 
1594 	i40e_rx_hash(rx_ring, rx_desc, skb, rx_ptype);
1595 
1596 	i40e_rx_checksum(rx_ring->vsi, skb, rx_desc);
1597 
1598 	skb_record_rx_queue(skb, rx_ring->queue_index);
1599 
1600 	/* modifies the skb - consumes the enet header */
1601 	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1602 }
1603 
1604 /**
1605  * i40e_cleanup_headers - Correct empty headers
1606  * @rx_ring: rx descriptor ring packet is being transacted on
1607  * @skb: pointer to current skb being fixed
1608  * @rx_desc: pointer to the EOP Rx descriptor
1609  *
1610  * Also address the case where we are pulling data in on pages only
1611  * and as such no data is present in the skb header.
1612  *
1613  * In addition if skb is not at least 60 bytes we need to pad it so that
1614  * it is large enough to qualify as a valid Ethernet frame.
1615  *
1616  * Returns true if an error was encountered and skb was freed.
1617  **/
1618 static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
1619 				 union i40e_rx_desc *rx_desc)
1620 
1621 {
1622 	/* XDP packets use error pointer so abort at this point */
1623 	if (IS_ERR(skb))
1624 		return true;
1625 
1626 	/* ERR_MASK will only have valid bits if EOP set, and
1627 	 * what we are doing here is actually checking
1628 	 * I40E_RX_DESC_ERROR_RXE_SHIFT, since it is the zeroth bit in
1629 	 * the error field
1630 	 */
1631 	if (unlikely(i40e_test_staterr(rx_desc,
1632 				       BIT(I40E_RXD_QW1_ERROR_SHIFT)))) {
1633 		dev_kfree_skb_any(skb);
1634 		return true;
1635 	}
1636 
1637 	/* if eth_skb_pad returns an error the skb was freed */
1638 	if (eth_skb_pad(skb))
1639 		return true;
1640 
1641 	return false;
1642 }
1643 
1644 /**
1645  * i40e_reuse_rx_page - page flip buffer and store it back on the ring
1646  * @rx_ring: rx descriptor ring to store buffers on
1647  * @old_buff: donor buffer to have page reused
1648  *
1649  * Synchronizes page for reuse by the adapter
1650  **/
1651 static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
1652 			       struct i40e_rx_buffer *old_buff)
1653 {
1654 	struct i40e_rx_buffer *new_buff;
1655 	u16 nta = rx_ring->next_to_alloc;
1656 
1657 	new_buff = &rx_ring->rx_bi[nta];
1658 
1659 	/* update, and store next to alloc */
1660 	nta++;
1661 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
1662 
1663 	/* transfer page from old buffer to new buffer */
1664 	new_buff->dma		= old_buff->dma;
1665 	new_buff->page		= old_buff->page;
1666 	new_buff->page_offset	= old_buff->page_offset;
1667 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
1668 }
1669 
1670 /**
1671  * i40e_page_is_reusable - check if any reuse is possible
1672  * @page: page struct to check
1673  *
1674  * A page is not reusable if it was allocated under low memory
1675  * conditions, or it's not in the same NUMA node as this CPU.
1676  */
1677 static inline bool i40e_page_is_reusable(struct page *page)
1678 {
1679 	return (page_to_nid(page) == numa_mem_id()) &&
1680 		!page_is_pfmemalloc(page);
1681 }
1682 
1683 /**
1684  * i40e_can_reuse_rx_page - Determine if this page can be reused by
1685  * the adapter for another receive
1686  *
1687  * @rx_buffer: buffer containing the page
1688  *
1689  * If page is reusable, rx_buffer->page_offset is adjusted to point to
1690  * an unused region in the page.
1691  *
1692  * For small pages, @truesize will be a constant value, half the size
1693  * of the memory at page.  We'll attempt to alternate between high and
1694  * low halves of the page, with one half ready for use by the hardware
1695  * and the other half being consumed by the stack.  We use the page
1696  * ref count to determine whether the stack has finished consuming the
1697  * portion of this page that was passed up with a previous packet.  If
1698  * the page ref count is >1, we'll assume the "other" half page is
1699  * still busy, and this page cannot be reused.
1700  *
1701  * For larger pages, @truesize will be the actual space used by the
1702  * received packet (adjusted upward to an even multiple of the cache
1703  * line size).  This will advance through the page by the amount
1704  * actually consumed by the received packets while there is still
1705  * space for a buffer.  Each region of larger pages will be used at
1706  * most once, after which the page will not be reused.
1707  *
1708  * In either case, if the page is reusable its refcount is increased.
1709  **/
1710 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer)
1711 {
1712 	unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
1713 	struct page *page = rx_buffer->page;
1714 
1715 	/* Is any reuse possible? */
1716 	if (unlikely(!i40e_page_is_reusable(page)))
1717 		return false;
1718 
1719 #if (PAGE_SIZE < 8192)
1720 	/* if we are only owner of page we can reuse it */
1721 	if (unlikely((page_count(page) - pagecnt_bias) > 1))
1722 		return false;
1723 #else
1724 #define I40E_LAST_OFFSET \
1725 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - I40E_RXBUFFER_2048)
1726 	if (rx_buffer->page_offset > I40E_LAST_OFFSET)
1727 		return false;
1728 #endif
1729 
1730 	/* If we have drained the page fragment pool we need to update
1731 	 * the pagecnt_bias and page count so that we fully restock the
1732 	 * number of references the driver holds.
1733 	 */
1734 	if (unlikely(!pagecnt_bias)) {
1735 		page_ref_add(page, USHRT_MAX);
1736 		rx_buffer->pagecnt_bias = USHRT_MAX;
1737 	}
1738 
1739 	return true;
1740 }
1741 
1742 /**
1743  * i40e_add_rx_frag - Add contents of Rx buffer to sk_buff
1744  * @rx_ring: rx descriptor ring to transact packets on
1745  * @rx_buffer: buffer containing page to add
1746  * @skb: sk_buff to place the data into
1747  * @size: packet length from rx_desc
1748  *
1749  * This function will add the data contained in rx_buffer->page to the skb.
1750  * It will just attach the page as a frag to the skb.
1751  *
1752  * The function will then update the page offset.
1753  **/
1754 static void i40e_add_rx_frag(struct i40e_ring *rx_ring,
1755 			     struct i40e_rx_buffer *rx_buffer,
1756 			     struct sk_buff *skb,
1757 			     unsigned int size)
1758 {
1759 #if (PAGE_SIZE < 8192)
1760 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1761 #else
1762 	unsigned int truesize = SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring));
1763 #endif
1764 
1765 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
1766 			rx_buffer->page_offset, size, truesize);
1767 
1768 	/* page is being used so we must update the page offset */
1769 #if (PAGE_SIZE < 8192)
1770 	rx_buffer->page_offset ^= truesize;
1771 #else
1772 	rx_buffer->page_offset += truesize;
1773 #endif
1774 }
1775 
1776 /**
1777  * i40e_get_rx_buffer - Fetch Rx buffer and synchronize data for use
1778  * @rx_ring: rx descriptor ring to transact packets on
1779  * @size: size of buffer to add to skb
1780  *
1781  * This function will pull an Rx buffer from the ring and synchronize it
1782  * for use by the CPU.
1783  */
1784 static struct i40e_rx_buffer *i40e_get_rx_buffer(struct i40e_ring *rx_ring,
1785 						 const unsigned int size)
1786 {
1787 	struct i40e_rx_buffer *rx_buffer;
1788 
1789 	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
1790 	prefetchw(rx_buffer->page);
1791 
1792 	/* we are reusing so sync this buffer for CPU use */
1793 	dma_sync_single_range_for_cpu(rx_ring->dev,
1794 				      rx_buffer->dma,
1795 				      rx_buffer->page_offset,
1796 				      size,
1797 				      DMA_FROM_DEVICE);
1798 
1799 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
1800 	rx_buffer->pagecnt_bias--;
1801 
1802 	return rx_buffer;
1803 }
1804 
1805 /**
1806  * i40e_construct_skb - Allocate skb and populate it
1807  * @rx_ring: rx descriptor ring to transact packets on
1808  * @rx_buffer: rx buffer to pull data from
1809  * @xdp: xdp_buff pointing to the data
1810  *
1811  * This function allocates an skb.  It then populates it with the page
1812  * data from the current receive descriptor, taking care to set up the
1813  * skb correctly.
1814  */
1815 static struct sk_buff *i40e_construct_skb(struct i40e_ring *rx_ring,
1816 					  struct i40e_rx_buffer *rx_buffer,
1817 					  struct xdp_buff *xdp)
1818 {
1819 	unsigned int size = xdp->data_end - xdp->data;
1820 #if (PAGE_SIZE < 8192)
1821 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1822 #else
1823 	unsigned int truesize = SKB_DATA_ALIGN(size);
1824 #endif
1825 	unsigned int headlen;
1826 	struct sk_buff *skb;
1827 
1828 	/* prefetch first cache line of first page */
1829 	prefetch(xdp->data);
1830 #if L1_CACHE_BYTES < 128
1831 	prefetch(xdp->data + L1_CACHE_BYTES);
1832 #endif
1833 
1834 	/* allocate a skb to store the frags */
1835 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
1836 			       I40E_RX_HDR_SIZE,
1837 			       GFP_ATOMIC | __GFP_NOWARN);
1838 	if (unlikely(!skb))
1839 		return NULL;
1840 
1841 	/* Determine available headroom for copy */
1842 	headlen = size;
1843 	if (headlen > I40E_RX_HDR_SIZE)
1844 		headlen = eth_get_headlen(xdp->data, I40E_RX_HDR_SIZE);
1845 
1846 	/* align pull length to size of long to optimize memcpy performance */
1847 	memcpy(__skb_put(skb, headlen), xdp->data,
1848 	       ALIGN(headlen, sizeof(long)));
1849 
1850 	/* update all of the pointers */
1851 	size -= headlen;
1852 	if (size) {
1853 		skb_add_rx_frag(skb, 0, rx_buffer->page,
1854 				rx_buffer->page_offset + headlen,
1855 				size, truesize);
1856 
1857 		/* buffer is used by skb, update page_offset */
1858 #if (PAGE_SIZE < 8192)
1859 		rx_buffer->page_offset ^= truesize;
1860 #else
1861 		rx_buffer->page_offset += truesize;
1862 #endif
1863 	} else {
1864 		/* buffer is unused, reset bias back to rx_buffer */
1865 		rx_buffer->pagecnt_bias++;
1866 	}
1867 
1868 	return skb;
1869 }
1870 
1871 /**
1872  * i40e_build_skb - Build skb around an existing buffer
1873  * @rx_ring: Rx descriptor ring to transact packets on
1874  * @rx_buffer: Rx buffer to pull data from
1875  * @xdp: xdp_buff pointing to the data
1876  *
1877  * This function builds an skb around an existing Rx buffer, taking care
1878  * to set up the skb correctly and avoid any memcpy overhead.
1879  */
1880 static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
1881 				      struct i40e_rx_buffer *rx_buffer,
1882 				      struct xdp_buff *xdp)
1883 {
1884 	unsigned int size = xdp->data_end - xdp->data;
1885 #if (PAGE_SIZE < 8192)
1886 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1887 #else
1888 	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
1889 				SKB_DATA_ALIGN(I40E_SKB_PAD + size);
1890 #endif
1891 	struct sk_buff *skb;
1892 
1893 	/* prefetch first cache line of first page */
1894 	prefetch(xdp->data);
1895 #if L1_CACHE_BYTES < 128
1896 	prefetch(xdp->data + L1_CACHE_BYTES);
1897 #endif
1898 	/* build an skb around the page buffer */
1899 	skb = build_skb(xdp->data_hard_start, truesize);
1900 	if (unlikely(!skb))
1901 		return NULL;
1902 
1903 	/* update pointers within the skb to store the data */
1904 	skb_reserve(skb, I40E_SKB_PAD);
1905 	__skb_put(skb, size);
1906 
1907 	/* buffer is used by skb, update page_offset */
1908 #if (PAGE_SIZE < 8192)
1909 	rx_buffer->page_offset ^= truesize;
1910 #else
1911 	rx_buffer->page_offset += truesize;
1912 #endif
1913 
1914 	return skb;
1915 }
1916 
1917 /**
1918  * i40e_put_rx_buffer - Clean up used buffer and either recycle or free
1919  * @rx_ring: rx descriptor ring to transact packets on
1920  * @rx_buffer: rx buffer to pull data from
1921  *
1922  * This function will clean up the contents of the rx_buffer.  It will
1923  * either recycle the bufer or unmap it and free the associated resources.
1924  */
1925 static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
1926 			       struct i40e_rx_buffer *rx_buffer)
1927 {
1928 	if (i40e_can_reuse_rx_page(rx_buffer)) {
1929 		/* hand second half of page back to the ring */
1930 		i40e_reuse_rx_page(rx_ring, rx_buffer);
1931 		rx_ring->rx_stats.page_reuse_count++;
1932 	} else {
1933 		/* we are not reusing the buffer so unmap it */
1934 		dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
1935 				     i40e_rx_pg_size(rx_ring),
1936 				     DMA_FROM_DEVICE, I40E_RX_DMA_ATTR);
1937 		__page_frag_cache_drain(rx_buffer->page,
1938 					rx_buffer->pagecnt_bias);
1939 	}
1940 
1941 	/* clear contents of buffer_info */
1942 	rx_buffer->page = NULL;
1943 }
1944 
1945 /**
1946  * i40e_is_non_eop - process handling of non-EOP buffers
1947  * @rx_ring: Rx ring being processed
1948  * @rx_desc: Rx descriptor for current buffer
1949  * @skb: Current socket buffer containing buffer in progress
1950  *
1951  * This function updates next to clean.  If the buffer is an EOP buffer
1952  * this function exits returning false, otherwise it will place the
1953  * sk_buff in the next buffer to be chained and return true indicating
1954  * that this is in fact a non-EOP buffer.
1955  **/
1956 static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
1957 			    union i40e_rx_desc *rx_desc,
1958 			    struct sk_buff *skb)
1959 {
1960 	u32 ntc = rx_ring->next_to_clean + 1;
1961 
1962 	/* fetch, update, and store next to clean */
1963 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1964 	rx_ring->next_to_clean = ntc;
1965 
1966 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1967 
1968 	/* if we are the last buffer then there is nothing else to do */
1969 #define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
1970 	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))
1971 		return false;
1972 
1973 	rx_ring->rx_stats.non_eop_descs++;
1974 
1975 	return true;
1976 }
1977 
1978 #define I40E_XDP_PASS 0
1979 #define I40E_XDP_CONSUMED 1
1980 #define I40E_XDP_TX 2
1981 
1982 static int i40e_xmit_xdp_ring(struct xdp_buff *xdp,
1983 			      struct i40e_ring *xdp_ring);
1984 
1985 /**
1986  * i40e_run_xdp - run an XDP program
1987  * @rx_ring: Rx ring being processed
1988  * @xdp: XDP buffer containing the frame
1989  **/
1990 static struct sk_buff *i40e_run_xdp(struct i40e_ring *rx_ring,
1991 				    struct xdp_buff *xdp)
1992 {
1993 	int result = I40E_XDP_PASS;
1994 	struct i40e_ring *xdp_ring;
1995 	struct bpf_prog *xdp_prog;
1996 	u32 act;
1997 
1998 	rcu_read_lock();
1999 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
2000 
2001 	if (!xdp_prog)
2002 		goto xdp_out;
2003 
2004 	act = bpf_prog_run_xdp(xdp_prog, xdp);
2005 	switch (act) {
2006 	case XDP_PASS:
2007 		break;
2008 	case XDP_TX:
2009 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2010 		result = i40e_xmit_xdp_ring(xdp, xdp_ring);
2011 		break;
2012 	default:
2013 		bpf_warn_invalid_xdp_action(act);
2014 	case XDP_ABORTED:
2015 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
2016 		/* fallthrough -- handle aborts by dropping packet */
2017 	case XDP_DROP:
2018 		result = I40E_XDP_CONSUMED;
2019 		break;
2020 	}
2021 xdp_out:
2022 	rcu_read_unlock();
2023 	return ERR_PTR(-result);
2024 }
2025 
2026 /**
2027  * i40e_rx_buffer_flip - adjusted rx_buffer to point to an unused region
2028  * @rx_ring: Rx ring
2029  * @rx_buffer: Rx buffer to adjust
2030  * @size: Size of adjustment
2031  **/
2032 static void i40e_rx_buffer_flip(struct i40e_ring *rx_ring,
2033 				struct i40e_rx_buffer *rx_buffer,
2034 				unsigned int size)
2035 {
2036 #if (PAGE_SIZE < 8192)
2037 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
2038 
2039 	rx_buffer->page_offset ^= truesize;
2040 #else
2041 	unsigned int truesize = SKB_DATA_ALIGN(i40e_rx_offset(rx_ring) + size);
2042 
2043 	rx_buffer->page_offset += truesize;
2044 #endif
2045 }
2046 
2047 /**
2048  * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
2049  * @rx_ring: rx descriptor ring to transact packets on
2050  * @budget: Total limit on number of packets to process
2051  *
2052  * This function provides a "bounce buffer" approach to Rx interrupt
2053  * processing.  The advantage to this is that on systems that have
2054  * expensive overhead for IOMMU access this provides a means of avoiding
2055  * it by maintaining the mapping of the page to the system.
2056  *
2057  * Returns amount of work completed
2058  **/
2059 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
2060 {
2061 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
2062 	struct sk_buff *skb = rx_ring->skb;
2063 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
2064 	bool failure = false, xdp_xmit = false;
2065 
2066 	while (likely(total_rx_packets < budget)) {
2067 		struct i40e_rx_buffer *rx_buffer;
2068 		union i40e_rx_desc *rx_desc;
2069 		struct xdp_buff xdp;
2070 		unsigned int size;
2071 		u16 vlan_tag;
2072 		u8 rx_ptype;
2073 		u64 qword;
2074 
2075 		/* return some buffers to hardware, one at a time is too slow */
2076 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
2077 			failure = failure ||
2078 				  i40e_alloc_rx_buffers(rx_ring, cleaned_count);
2079 			cleaned_count = 0;
2080 		}
2081 
2082 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
2083 
2084 		/* status_error_len will always be zero for unused descriptors
2085 		 * because it's cleared in cleanup, and overlaps with hdr_addr
2086 		 * which is always zero because packet split isn't used, if the
2087 		 * hardware wrote DD then the length will be non-zero
2088 		 */
2089 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2090 
2091 		/* This memory barrier is needed to keep us from reading
2092 		 * any other fields out of the rx_desc until we have
2093 		 * verified the descriptor has been written back.
2094 		 */
2095 		dma_rmb();
2096 
2097 		if (unlikely(i40e_rx_is_programming_status(qword))) {
2098 			i40e_clean_programming_status(rx_ring, rx_desc, qword);
2099 			continue;
2100 		}
2101 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
2102 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
2103 		if (!size)
2104 			break;
2105 
2106 		i40e_trace(clean_rx_irq, rx_ring, rx_desc, skb);
2107 		rx_buffer = i40e_get_rx_buffer(rx_ring, size);
2108 
2109 		/* retrieve a buffer from the ring */
2110 		if (!skb) {
2111 			xdp.data = page_address(rx_buffer->page) +
2112 				   rx_buffer->page_offset;
2113 			xdp.data_hard_start = xdp.data -
2114 					      i40e_rx_offset(rx_ring);
2115 			xdp.data_end = xdp.data + size;
2116 
2117 			skb = i40e_run_xdp(rx_ring, &xdp);
2118 		}
2119 
2120 		if (IS_ERR(skb)) {
2121 			if (PTR_ERR(skb) == -I40E_XDP_TX) {
2122 				xdp_xmit = true;
2123 				i40e_rx_buffer_flip(rx_ring, rx_buffer, size);
2124 			} else {
2125 				rx_buffer->pagecnt_bias++;
2126 			}
2127 			total_rx_bytes += size;
2128 			total_rx_packets++;
2129 		} else if (skb) {
2130 			i40e_add_rx_frag(rx_ring, rx_buffer, skb, size);
2131 		} else if (ring_uses_build_skb(rx_ring)) {
2132 			skb = i40e_build_skb(rx_ring, rx_buffer, &xdp);
2133 		} else {
2134 			skb = i40e_construct_skb(rx_ring, rx_buffer, &xdp);
2135 		}
2136 
2137 		/* exit if we failed to retrieve a buffer */
2138 		if (!skb) {
2139 			rx_ring->rx_stats.alloc_buff_failed++;
2140 			rx_buffer->pagecnt_bias++;
2141 			break;
2142 		}
2143 
2144 		i40e_put_rx_buffer(rx_ring, rx_buffer);
2145 		cleaned_count++;
2146 
2147 		if (i40e_is_non_eop(rx_ring, rx_desc, skb))
2148 			continue;
2149 
2150 		if (i40e_cleanup_headers(rx_ring, skb, rx_desc)) {
2151 			skb = NULL;
2152 			continue;
2153 		}
2154 
2155 		/* probably a little skewed due to removing CRC */
2156 		total_rx_bytes += skb->len;
2157 
2158 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2159 		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
2160 			   I40E_RXD_QW1_PTYPE_SHIFT;
2161 
2162 		/* populate checksum, VLAN, and protocol */
2163 		i40e_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
2164 
2165 		vlan_tag = (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) ?
2166 			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;
2167 
2168 		i40e_trace(clean_rx_irq_rx, rx_ring, rx_desc, skb);
2169 		i40e_receive_skb(rx_ring, skb, vlan_tag);
2170 		skb = NULL;
2171 
2172 		/* update budget accounting */
2173 		total_rx_packets++;
2174 	}
2175 
2176 	if (xdp_xmit) {
2177 		struct i40e_ring *xdp_ring;
2178 
2179 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2180 
2181 		/* Force memory writes to complete before letting h/w
2182 		 * know there are new descriptors to fetch.
2183 		 */
2184 		wmb();
2185 
2186 		writel(xdp_ring->next_to_use, xdp_ring->tail);
2187 	}
2188 
2189 	rx_ring->skb = skb;
2190 
2191 	u64_stats_update_begin(&rx_ring->syncp);
2192 	rx_ring->stats.packets += total_rx_packets;
2193 	rx_ring->stats.bytes += total_rx_bytes;
2194 	u64_stats_update_end(&rx_ring->syncp);
2195 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
2196 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
2197 
2198 	/* guarantee a trip back through this routine if there was a failure */
2199 	return failure ? budget : total_rx_packets;
2200 }
2201 
2202 static u32 i40e_buildreg_itr(const int type, const u16 itr)
2203 {
2204 	u32 val;
2205 
2206 	val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
2207 	      /* Don't clear PBA because that can cause lost interrupts that
2208 	       * came in while we were cleaning/polling
2209 	       */
2210 	      (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
2211 	      (itr << I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT);
2212 
2213 	return val;
2214 }
2215 
2216 /* a small macro to shorten up some long lines */
2217 #define INTREG I40E_PFINT_DYN_CTLN
2218 static inline int get_rx_itr(struct i40e_vsi *vsi, int idx)
2219 {
2220 	return vsi->rx_rings[idx]->rx_itr_setting;
2221 }
2222 
2223 static inline int get_tx_itr(struct i40e_vsi *vsi, int idx)
2224 {
2225 	return vsi->tx_rings[idx]->tx_itr_setting;
2226 }
2227 
2228 /**
2229  * i40e_update_enable_itr - Update itr and re-enable MSIX interrupt
2230  * @vsi: the VSI we care about
2231  * @q_vector: q_vector for which itr is being updated and interrupt enabled
2232  *
2233  **/
2234 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
2235 					  struct i40e_q_vector *q_vector)
2236 {
2237 	struct i40e_hw *hw = &vsi->back->hw;
2238 	bool rx = false, tx = false;
2239 	u32 rxval, txval;
2240 	int vector;
2241 	int idx = q_vector->v_idx;
2242 	int rx_itr_setting, tx_itr_setting;
2243 
2244 	vector = (q_vector->v_idx + vsi->base_vector);
2245 
2246 	/* avoid dynamic calculation if in countdown mode OR if
2247 	 * all dynamic is disabled
2248 	 */
2249 	rxval = txval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
2250 
2251 	rx_itr_setting = get_rx_itr(vsi, idx);
2252 	tx_itr_setting = get_tx_itr(vsi, idx);
2253 
2254 	if (q_vector->itr_countdown > 0 ||
2255 	    (!ITR_IS_DYNAMIC(rx_itr_setting) &&
2256 	     !ITR_IS_DYNAMIC(tx_itr_setting))) {
2257 		goto enable_int;
2258 	}
2259 
2260 	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
2261 		rx = i40e_set_new_dynamic_itr(&q_vector->rx);
2262 		rxval = i40e_buildreg_itr(I40E_RX_ITR, q_vector->rx.itr);
2263 	}
2264 
2265 	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
2266 		tx = i40e_set_new_dynamic_itr(&q_vector->tx);
2267 		txval = i40e_buildreg_itr(I40E_TX_ITR, q_vector->tx.itr);
2268 	}
2269 
2270 	if (rx || tx) {
2271 		/* get the higher of the two ITR adjustments and
2272 		 * use the same value for both ITR registers
2273 		 * when in adaptive mode (Rx and/or Tx)
2274 		 */
2275 		u16 itr = max(q_vector->tx.itr, q_vector->rx.itr);
2276 
2277 		q_vector->tx.itr = q_vector->rx.itr = itr;
2278 		txval = i40e_buildreg_itr(I40E_TX_ITR, itr);
2279 		tx = true;
2280 		rxval = i40e_buildreg_itr(I40E_RX_ITR, itr);
2281 		rx = true;
2282 	}
2283 
2284 	/* only need to enable the interrupt once, but need
2285 	 * to possibly update both ITR values
2286 	 */
2287 	if (rx) {
2288 		/* set the INTENA_MSK_MASK so that this first write
2289 		 * won't actually enable the interrupt, instead just
2290 		 * updating the ITR (it's bit 31 PF and VF)
2291 		 */
2292 		rxval |= BIT(31);
2293 		/* don't check _DOWN because interrupt isn't being enabled */
2294 		wr32(hw, INTREG(vector - 1), rxval);
2295 	}
2296 
2297 enable_int:
2298 	if (!test_bit(__I40E_VSI_DOWN, vsi->state))
2299 		wr32(hw, INTREG(vector - 1), txval);
2300 
2301 	if (q_vector->itr_countdown)
2302 		q_vector->itr_countdown--;
2303 	else
2304 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2305 }
2306 
2307 /**
2308  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
2309  * @napi: napi struct with our devices info in it
2310  * @budget: amount of work driver is allowed to do this pass, in packets
2311  *
2312  * This function will clean all queues associated with a q_vector.
2313  *
2314  * Returns the amount of work done
2315  **/
2316 int i40e_napi_poll(struct napi_struct *napi, int budget)
2317 {
2318 	struct i40e_q_vector *q_vector =
2319 			       container_of(napi, struct i40e_q_vector, napi);
2320 	struct i40e_vsi *vsi = q_vector->vsi;
2321 	struct i40e_ring *ring;
2322 	bool clean_complete = true;
2323 	bool arm_wb = false;
2324 	int budget_per_ring;
2325 	int work_done = 0;
2326 
2327 	if (test_bit(__I40E_VSI_DOWN, vsi->state)) {
2328 		napi_complete(napi);
2329 		return 0;
2330 	}
2331 
2332 	/* Since the actual Tx work is minimal, we can give the Tx a larger
2333 	 * budget and be more aggressive about cleaning up the Tx descriptors.
2334 	 */
2335 	i40e_for_each_ring(ring, q_vector->tx) {
2336 		if (!i40e_clean_tx_irq(vsi, ring, budget)) {
2337 			clean_complete = false;
2338 			continue;
2339 		}
2340 		arm_wb |= ring->arm_wb;
2341 		ring->arm_wb = false;
2342 	}
2343 
2344 	/* Handle case where we are called by netpoll with a budget of 0 */
2345 	if (budget <= 0)
2346 		goto tx_only;
2347 
2348 	/* We attempt to distribute budget to each Rx queue fairly, but don't
2349 	 * allow the budget to go below 1 because that would exit polling early.
2350 	 */
2351 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
2352 
2353 	i40e_for_each_ring(ring, q_vector->rx) {
2354 		int cleaned = i40e_clean_rx_irq(ring, budget_per_ring);
2355 
2356 		work_done += cleaned;
2357 		/* if we clean as many as budgeted, we must not be done */
2358 		if (cleaned >= budget_per_ring)
2359 			clean_complete = false;
2360 	}
2361 
2362 	/* If work not completed, return budget and polling will return */
2363 	if (!clean_complete) {
2364 		const cpumask_t *aff_mask = &q_vector->affinity_mask;
2365 		int cpu_id = smp_processor_id();
2366 
2367 		/* It is possible that the interrupt affinity has changed but,
2368 		 * if the cpu is pegged at 100%, polling will never exit while
2369 		 * traffic continues and the interrupt will be stuck on this
2370 		 * cpu.  We check to make sure affinity is correct before we
2371 		 * continue to poll, otherwise we must stop polling so the
2372 		 * interrupt can move to the correct cpu.
2373 		 */
2374 		if (likely(cpumask_test_cpu(cpu_id, aff_mask) ||
2375 			   !(vsi->back->flags & I40E_FLAG_MSIX_ENABLED))) {
2376 tx_only:
2377 			if (arm_wb) {
2378 				q_vector->tx.ring[0].tx_stats.tx_force_wb++;
2379 				i40e_enable_wb_on_itr(vsi, q_vector);
2380 			}
2381 			return budget;
2382 		}
2383 	}
2384 
2385 	if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR)
2386 		q_vector->arm_wb_state = false;
2387 
2388 	/* Work is done so exit the polling mode and re-enable the interrupt */
2389 	napi_complete_done(napi, work_done);
2390 
2391 	/* If we're prematurely stopping polling to fix the interrupt
2392 	 * affinity we want to make sure polling starts back up so we
2393 	 * issue a call to i40e_force_wb which triggers a SW interrupt.
2394 	 */
2395 	if (!clean_complete)
2396 		i40e_force_wb(vsi, q_vector);
2397 	else if (!(vsi->back->flags & I40E_FLAG_MSIX_ENABLED))
2398 		i40e_irq_dynamic_enable_icr0(vsi->back, false);
2399 	else
2400 		i40e_update_enable_itr(vsi, q_vector);
2401 
2402 	return min(work_done, budget - 1);
2403 }
2404 
2405 /**
2406  * i40e_atr - Add a Flow Director ATR filter
2407  * @tx_ring:  ring to add programming descriptor to
2408  * @skb:      send buffer
2409  * @tx_flags: send tx flags
2410  **/
2411 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
2412 		     u32 tx_flags)
2413 {
2414 	struct i40e_filter_program_desc *fdir_desc;
2415 	struct i40e_pf *pf = tx_ring->vsi->back;
2416 	union {
2417 		unsigned char *network;
2418 		struct iphdr *ipv4;
2419 		struct ipv6hdr *ipv6;
2420 	} hdr;
2421 	struct tcphdr *th;
2422 	unsigned int hlen;
2423 	u32 flex_ptype, dtype_cmd;
2424 	int l4_proto;
2425 	u16 i;
2426 
2427 	/* make sure ATR is enabled */
2428 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
2429 		return;
2430 
2431 	if (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED)
2432 		return;
2433 
2434 	/* if sampling is disabled do nothing */
2435 	if (!tx_ring->atr_sample_rate)
2436 		return;
2437 
2438 	/* Currently only IPv4/IPv6 with TCP is supported */
2439 	if (!(tx_flags & (I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6)))
2440 		return;
2441 
2442 	/* snag network header to get L4 type and address */
2443 	hdr.network = (tx_flags & I40E_TX_FLAGS_UDP_TUNNEL) ?
2444 		      skb_inner_network_header(skb) : skb_network_header(skb);
2445 
2446 	/* Note: tx_flags gets modified to reflect inner protocols in
2447 	 * tx_enable_csum function if encap is enabled.
2448 	 */
2449 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2450 		/* access ihl as u8 to avoid unaligned access on ia64 */
2451 		hlen = (hdr.network[0] & 0x0F) << 2;
2452 		l4_proto = hdr.ipv4->protocol;
2453 	} else {
2454 		hlen = hdr.network - skb->data;
2455 		l4_proto = ipv6_find_hdr(skb, &hlen, IPPROTO_TCP, NULL, NULL);
2456 		hlen -= hdr.network - skb->data;
2457 	}
2458 
2459 	if (l4_proto != IPPROTO_TCP)
2460 		return;
2461 
2462 	th = (struct tcphdr *)(hdr.network + hlen);
2463 
2464 	/* Due to lack of space, no more new filters can be programmed */
2465 	if (th->syn && (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED))
2466 		return;
2467 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED) {
2468 		/* HW ATR eviction will take care of removing filters on FIN
2469 		 * and RST packets.
2470 		 */
2471 		if (th->fin || th->rst)
2472 			return;
2473 	}
2474 
2475 	tx_ring->atr_count++;
2476 
2477 	/* sample on all syn/fin/rst packets or once every atr sample rate */
2478 	if (!th->fin &&
2479 	    !th->syn &&
2480 	    !th->rst &&
2481 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
2482 		return;
2483 
2484 	tx_ring->atr_count = 0;
2485 
2486 	/* grab the next descriptor */
2487 	i = tx_ring->next_to_use;
2488 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
2489 
2490 	i++;
2491 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2492 
2493 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
2494 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
2495 	flex_ptype |= (tx_flags & I40E_TX_FLAGS_IPV4) ?
2496 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
2497 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
2498 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
2499 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
2500 
2501 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
2502 
2503 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
2504 
2505 	dtype_cmd |= (th->fin || th->rst) ?
2506 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
2507 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
2508 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
2509 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
2510 
2511 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
2512 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
2513 
2514 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
2515 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
2516 
2517 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
2518 	if (!(tx_flags & I40E_TX_FLAGS_UDP_TUNNEL))
2519 		dtype_cmd |=
2520 			((u32)I40E_FD_ATR_STAT_IDX(pf->hw.pf_id) <<
2521 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2522 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2523 	else
2524 		dtype_cmd |=
2525 			((u32)I40E_FD_ATR_TUNNEL_STAT_IDX(pf->hw.pf_id) <<
2526 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2527 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2528 
2529 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED)
2530 		dtype_cmd |= I40E_TXD_FLTR_QW1_ATR_MASK;
2531 
2532 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
2533 	fdir_desc->rsvd = cpu_to_le32(0);
2534 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
2535 	fdir_desc->fd_id = cpu_to_le32(0);
2536 }
2537 
2538 /**
2539  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
2540  * @skb:     send buffer
2541  * @tx_ring: ring to send buffer on
2542  * @flags:   the tx flags to be set
2543  *
2544  * Checks the skb and set up correspondingly several generic transmit flags
2545  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2546  *
2547  * Returns error code indicate the frame should be dropped upon error and the
2548  * otherwise  returns 0 to indicate the flags has been set properly.
2549  **/
2550 static inline int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2551 					     struct i40e_ring *tx_ring,
2552 					     u32 *flags)
2553 {
2554 	__be16 protocol = skb->protocol;
2555 	u32  tx_flags = 0;
2556 
2557 	if (protocol == htons(ETH_P_8021Q) &&
2558 	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
2559 		/* When HW VLAN acceleration is turned off by the user the
2560 		 * stack sets the protocol to 8021q so that the driver
2561 		 * can take any steps required to support the SW only
2562 		 * VLAN handling.  In our case the driver doesn't need
2563 		 * to take any further steps so just set the protocol
2564 		 * to the encapsulated ethertype.
2565 		 */
2566 		skb->protocol = vlan_get_protocol(skb);
2567 		goto out;
2568 	}
2569 
2570 	/* if we have a HW VLAN tag being added, default to the HW one */
2571 	if (skb_vlan_tag_present(skb)) {
2572 		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
2573 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2574 	/* else if it is a SW VLAN, check the next protocol and store the tag */
2575 	} else if (protocol == htons(ETH_P_8021Q)) {
2576 		struct vlan_hdr *vhdr, _vhdr;
2577 
2578 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
2579 		if (!vhdr)
2580 			return -EINVAL;
2581 
2582 		protocol = vhdr->h_vlan_encapsulated_proto;
2583 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
2584 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
2585 	}
2586 
2587 	if (!(tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED))
2588 		goto out;
2589 
2590 	/* Insert 802.1p priority into VLAN header */
2591 	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
2592 	    (skb->priority != TC_PRIO_CONTROL)) {
2593 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
2594 		tx_flags |= (skb->priority & 0x7) <<
2595 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
2596 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
2597 			struct vlan_ethhdr *vhdr;
2598 			int rc;
2599 
2600 			rc = skb_cow_head(skb, 0);
2601 			if (rc < 0)
2602 				return rc;
2603 			vhdr = (struct vlan_ethhdr *)skb->data;
2604 			vhdr->h_vlan_TCI = htons(tx_flags >>
2605 						 I40E_TX_FLAGS_VLAN_SHIFT);
2606 		} else {
2607 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2608 		}
2609 	}
2610 
2611 out:
2612 	*flags = tx_flags;
2613 	return 0;
2614 }
2615 
2616 /**
2617  * i40e_tso - set up the tso context descriptor
2618  * @first:    pointer to first Tx buffer for xmit
2619  * @hdr_len:  ptr to the size of the packet header
2620  * @cd_type_cmd_tso_mss: Quad Word 1
2621  *
2622  * Returns 0 if no TSO can happen, 1 if tso is going, or error
2623  **/
2624 static int i40e_tso(struct i40e_tx_buffer *first, u8 *hdr_len,
2625 		    u64 *cd_type_cmd_tso_mss)
2626 {
2627 	struct sk_buff *skb = first->skb;
2628 	u64 cd_cmd, cd_tso_len, cd_mss;
2629 	union {
2630 		struct iphdr *v4;
2631 		struct ipv6hdr *v6;
2632 		unsigned char *hdr;
2633 	} ip;
2634 	union {
2635 		struct tcphdr *tcp;
2636 		struct udphdr *udp;
2637 		unsigned char *hdr;
2638 	} l4;
2639 	u32 paylen, l4_offset;
2640 	u16 gso_segs, gso_size;
2641 	int err;
2642 
2643 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2644 		return 0;
2645 
2646 	if (!skb_is_gso(skb))
2647 		return 0;
2648 
2649 	err = skb_cow_head(skb, 0);
2650 	if (err < 0)
2651 		return err;
2652 
2653 	ip.hdr = skb_network_header(skb);
2654 	l4.hdr = skb_transport_header(skb);
2655 
2656 	/* initialize outer IP header fields */
2657 	if (ip.v4->version == 4) {
2658 		ip.v4->tot_len = 0;
2659 		ip.v4->check = 0;
2660 	} else {
2661 		ip.v6->payload_len = 0;
2662 	}
2663 
2664 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2665 					 SKB_GSO_GRE_CSUM |
2666 					 SKB_GSO_IPXIP4 |
2667 					 SKB_GSO_IPXIP6 |
2668 					 SKB_GSO_UDP_TUNNEL |
2669 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2670 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2671 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2672 			l4.udp->len = 0;
2673 
2674 			/* determine offset of outer transport header */
2675 			l4_offset = l4.hdr - skb->data;
2676 
2677 			/* remove payload length from outer checksum */
2678 			paylen = skb->len - l4_offset;
2679 			csum_replace_by_diff(&l4.udp->check,
2680 					     (__force __wsum)htonl(paylen));
2681 		}
2682 
2683 		/* reset pointers to inner headers */
2684 		ip.hdr = skb_inner_network_header(skb);
2685 		l4.hdr = skb_inner_transport_header(skb);
2686 
2687 		/* initialize inner IP header fields */
2688 		if (ip.v4->version == 4) {
2689 			ip.v4->tot_len = 0;
2690 			ip.v4->check = 0;
2691 		} else {
2692 			ip.v6->payload_len = 0;
2693 		}
2694 	}
2695 
2696 	/* determine offset of inner transport header */
2697 	l4_offset = l4.hdr - skb->data;
2698 
2699 	/* remove payload length from inner checksum */
2700 	paylen = skb->len - l4_offset;
2701 	csum_replace_by_diff(&l4.tcp->check, (__force __wsum)htonl(paylen));
2702 
2703 	/* compute length of segmentation header */
2704 	*hdr_len = (l4.tcp->doff * 4) + l4_offset;
2705 
2706 	/* pull values out of skb_shinfo */
2707 	gso_size = skb_shinfo(skb)->gso_size;
2708 	gso_segs = skb_shinfo(skb)->gso_segs;
2709 
2710 	/* update GSO size and bytecount with header size */
2711 	first->gso_segs = gso_segs;
2712 	first->bytecount += (first->gso_segs - 1) * *hdr_len;
2713 
2714 	/* find the field values */
2715 	cd_cmd = I40E_TX_CTX_DESC_TSO;
2716 	cd_tso_len = skb->len - *hdr_len;
2717 	cd_mss = gso_size;
2718 	*cd_type_cmd_tso_mss |= (cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
2719 				(cd_tso_len << I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
2720 				(cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
2721 	return 1;
2722 }
2723 
2724 /**
2725  * i40e_tsyn - set up the tsyn context descriptor
2726  * @tx_ring:  ptr to the ring to send
2727  * @skb:      ptr to the skb we're sending
2728  * @tx_flags: the collected send information
2729  * @cd_type_cmd_tso_mss: Quad Word 1
2730  *
2731  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
2732  **/
2733 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
2734 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
2735 {
2736 	struct i40e_pf *pf;
2737 
2738 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2739 		return 0;
2740 
2741 	/* Tx timestamps cannot be sampled when doing TSO */
2742 	if (tx_flags & I40E_TX_FLAGS_TSO)
2743 		return 0;
2744 
2745 	/* only timestamp the outbound packet if the user has requested it and
2746 	 * we are not already transmitting a packet to be timestamped
2747 	 */
2748 	pf = i40e_netdev_to_pf(tx_ring->netdev);
2749 	if (!(pf->flags & I40E_FLAG_PTP))
2750 		return 0;
2751 
2752 	if (pf->ptp_tx &&
2753 	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, pf->state)) {
2754 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2755 		pf->ptp_tx_start = jiffies;
2756 		pf->ptp_tx_skb = skb_get(skb);
2757 	} else {
2758 		pf->tx_hwtstamp_skipped++;
2759 		return 0;
2760 	}
2761 
2762 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
2763 				I40E_TXD_CTX_QW1_CMD_SHIFT;
2764 
2765 	return 1;
2766 }
2767 
2768 /**
2769  * i40e_tx_enable_csum - Enable Tx checksum offloads
2770  * @skb: send buffer
2771  * @tx_flags: pointer to Tx flags currently set
2772  * @td_cmd: Tx descriptor command bits to set
2773  * @td_offset: Tx descriptor header offsets to set
2774  * @tx_ring: Tx descriptor ring
2775  * @cd_tunneling: ptr to context desc bits
2776  **/
2777 static int i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
2778 			       u32 *td_cmd, u32 *td_offset,
2779 			       struct i40e_ring *tx_ring,
2780 			       u32 *cd_tunneling)
2781 {
2782 	union {
2783 		struct iphdr *v4;
2784 		struct ipv6hdr *v6;
2785 		unsigned char *hdr;
2786 	} ip;
2787 	union {
2788 		struct tcphdr *tcp;
2789 		struct udphdr *udp;
2790 		unsigned char *hdr;
2791 	} l4;
2792 	unsigned char *exthdr;
2793 	u32 offset, cmd = 0;
2794 	__be16 frag_off;
2795 	u8 l4_proto = 0;
2796 
2797 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2798 		return 0;
2799 
2800 	ip.hdr = skb_network_header(skb);
2801 	l4.hdr = skb_transport_header(skb);
2802 
2803 	/* compute outer L2 header size */
2804 	offset = ((ip.hdr - skb->data) / 2) << I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
2805 
2806 	if (skb->encapsulation) {
2807 		u32 tunnel = 0;
2808 		/* define outer network header type */
2809 		if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2810 			tunnel |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2811 				  I40E_TX_CTX_EXT_IP_IPV4 :
2812 				  I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
2813 
2814 			l4_proto = ip.v4->protocol;
2815 		} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2816 			tunnel |= I40E_TX_CTX_EXT_IP_IPV6;
2817 
2818 			exthdr = ip.hdr + sizeof(*ip.v6);
2819 			l4_proto = ip.v6->nexthdr;
2820 			if (l4.hdr != exthdr)
2821 				ipv6_skip_exthdr(skb, exthdr - skb->data,
2822 						 &l4_proto, &frag_off);
2823 		}
2824 
2825 		/* define outer transport */
2826 		switch (l4_proto) {
2827 		case IPPROTO_UDP:
2828 			tunnel |= I40E_TXD_CTX_UDP_TUNNELING;
2829 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2830 			break;
2831 		case IPPROTO_GRE:
2832 			tunnel |= I40E_TXD_CTX_GRE_TUNNELING;
2833 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2834 			break;
2835 		case IPPROTO_IPIP:
2836 		case IPPROTO_IPV6:
2837 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2838 			l4.hdr = skb_inner_network_header(skb);
2839 			break;
2840 		default:
2841 			if (*tx_flags & I40E_TX_FLAGS_TSO)
2842 				return -1;
2843 
2844 			skb_checksum_help(skb);
2845 			return 0;
2846 		}
2847 
2848 		/* compute outer L3 header size */
2849 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
2850 			  I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT;
2851 
2852 		/* switch IP header pointer from outer to inner header */
2853 		ip.hdr = skb_inner_network_header(skb);
2854 
2855 		/* compute tunnel header size */
2856 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
2857 			  I40E_TXD_CTX_QW0_NATLEN_SHIFT;
2858 
2859 		/* indicate if we need to offload outer UDP header */
2860 		if ((*tx_flags & I40E_TX_FLAGS_TSO) &&
2861 		    !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2862 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
2863 			tunnel |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
2864 
2865 		/* record tunnel offload values */
2866 		*cd_tunneling |= tunnel;
2867 
2868 		/* switch L4 header pointer from outer to inner */
2869 		l4.hdr = skb_inner_transport_header(skb);
2870 		l4_proto = 0;
2871 
2872 		/* reset type as we transition from outer to inner headers */
2873 		*tx_flags &= ~(I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6);
2874 		if (ip.v4->version == 4)
2875 			*tx_flags |= I40E_TX_FLAGS_IPV4;
2876 		if (ip.v6->version == 6)
2877 			*tx_flags |= I40E_TX_FLAGS_IPV6;
2878 	}
2879 
2880 	/* Enable IP checksum offloads */
2881 	if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2882 		l4_proto = ip.v4->protocol;
2883 		/* the stack computes the IP header already, the only time we
2884 		 * need the hardware to recompute it is in the case of TSO.
2885 		 */
2886 		cmd |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2887 		       I40E_TX_DESC_CMD_IIPT_IPV4_CSUM :
2888 		       I40E_TX_DESC_CMD_IIPT_IPV4;
2889 	} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2890 		cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
2891 
2892 		exthdr = ip.hdr + sizeof(*ip.v6);
2893 		l4_proto = ip.v6->nexthdr;
2894 		if (l4.hdr != exthdr)
2895 			ipv6_skip_exthdr(skb, exthdr - skb->data,
2896 					 &l4_proto, &frag_off);
2897 	}
2898 
2899 	/* compute inner L3 header size */
2900 	offset |= ((l4.hdr - ip.hdr) / 4) << I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2901 
2902 	/* Enable L4 checksum offloads */
2903 	switch (l4_proto) {
2904 	case IPPROTO_TCP:
2905 		/* enable checksum offloads */
2906 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
2907 		offset |= l4.tcp->doff << I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2908 		break;
2909 	case IPPROTO_SCTP:
2910 		/* enable SCTP checksum offload */
2911 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
2912 		offset |= (sizeof(struct sctphdr) >> 2) <<
2913 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2914 		break;
2915 	case IPPROTO_UDP:
2916 		/* enable UDP checksum offload */
2917 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
2918 		offset |= (sizeof(struct udphdr) >> 2) <<
2919 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2920 		break;
2921 	default:
2922 		if (*tx_flags & I40E_TX_FLAGS_TSO)
2923 			return -1;
2924 		skb_checksum_help(skb);
2925 		return 0;
2926 	}
2927 
2928 	*td_cmd |= cmd;
2929 	*td_offset |= offset;
2930 
2931 	return 1;
2932 }
2933 
2934 /**
2935  * i40e_create_tx_ctx Build the Tx context descriptor
2936  * @tx_ring:  ring to create the descriptor on
2937  * @cd_type_cmd_tso_mss: Quad Word 1
2938  * @cd_tunneling: Quad Word 0 - bits 0-31
2939  * @cd_l2tag2: Quad Word 0 - bits 32-63
2940  **/
2941 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
2942 			       const u64 cd_type_cmd_tso_mss,
2943 			       const u32 cd_tunneling, const u32 cd_l2tag2)
2944 {
2945 	struct i40e_tx_context_desc *context_desc;
2946 	int i = tx_ring->next_to_use;
2947 
2948 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
2949 	    !cd_tunneling && !cd_l2tag2)
2950 		return;
2951 
2952 	/* grab the next descriptor */
2953 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
2954 
2955 	i++;
2956 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2957 
2958 	/* cpu_to_le32 and assign to struct fields */
2959 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2960 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2961 	context_desc->rsvd = cpu_to_le16(0);
2962 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2963 }
2964 
2965 /**
2966  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2967  * @tx_ring: the ring to be checked
2968  * @size:    the size buffer we want to assure is available
2969  *
2970  * Returns -EBUSY if a stop is needed, else 0
2971  **/
2972 int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2973 {
2974 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2975 	/* Memory barrier before checking head and tail */
2976 	smp_mb();
2977 
2978 	/* Check again in a case another CPU has just made room available. */
2979 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2980 		return -EBUSY;
2981 
2982 	/* A reprieve! - use start_queue because it doesn't call schedule */
2983 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
2984 	++tx_ring->tx_stats.restart_queue;
2985 	return 0;
2986 }
2987 
2988 /**
2989  * __i40e_chk_linearize - Check if there are more than 8 buffers per packet
2990  * @skb:      send buffer
2991  *
2992  * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
2993  * and so we need to figure out the cases where we need to linearize the skb.
2994  *
2995  * For TSO we need to count the TSO header and segment payload separately.
2996  * As such we need to check cases where we have 7 fragments or more as we
2997  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2998  * the segment payload in the first descriptor, and another 7 for the
2999  * fragments.
3000  **/
3001 bool __i40e_chk_linearize(struct sk_buff *skb)
3002 {
3003 	const struct skb_frag_struct *frag, *stale;
3004 	int nr_frags, sum;
3005 
3006 	/* no need to check if number of frags is less than 7 */
3007 	nr_frags = skb_shinfo(skb)->nr_frags;
3008 	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
3009 		return false;
3010 
3011 	/* We need to walk through the list and validate that each group
3012 	 * of 6 fragments totals at least gso_size.
3013 	 */
3014 	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
3015 	frag = &skb_shinfo(skb)->frags[0];
3016 
3017 	/* Initialize size to the negative value of gso_size minus 1.  We
3018 	 * use this as the worst case scenerio in which the frag ahead
3019 	 * of us only provides one byte which is why we are limited to 6
3020 	 * descriptors for a single transmit as the header and previous
3021 	 * fragment are already consuming 2 descriptors.
3022 	 */
3023 	sum = 1 - skb_shinfo(skb)->gso_size;
3024 
3025 	/* Add size of frags 0 through 4 to create our initial sum */
3026 	sum += skb_frag_size(frag++);
3027 	sum += skb_frag_size(frag++);
3028 	sum += skb_frag_size(frag++);
3029 	sum += skb_frag_size(frag++);
3030 	sum += skb_frag_size(frag++);
3031 
3032 	/* Walk through fragments adding latest fragment, testing it, and
3033 	 * then removing stale fragments from the sum.
3034 	 */
3035 	stale = &skb_shinfo(skb)->frags[0];
3036 	for (;;) {
3037 		sum += skb_frag_size(frag++);
3038 
3039 		/* if sum is negative we failed to make sufficient progress */
3040 		if (sum < 0)
3041 			return true;
3042 
3043 		if (!nr_frags--)
3044 			break;
3045 
3046 		sum -= skb_frag_size(stale++);
3047 	}
3048 
3049 	return false;
3050 }
3051 
3052 /**
3053  * i40e_tx_map - Build the Tx descriptor
3054  * @tx_ring:  ring to send buffer on
3055  * @skb:      send buffer
3056  * @first:    first buffer info buffer to use
3057  * @tx_flags: collected send information
3058  * @hdr_len:  size of the packet header
3059  * @td_cmd:   the command field in the descriptor
3060  * @td_offset: offset for checksum or crc
3061  *
3062  * Returns 0 on success, -1 on failure to DMA
3063  **/
3064 static inline int i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
3065 			      struct i40e_tx_buffer *first, u32 tx_flags,
3066 			      const u8 hdr_len, u32 td_cmd, u32 td_offset)
3067 {
3068 	unsigned int data_len = skb->data_len;
3069 	unsigned int size = skb_headlen(skb);
3070 	struct skb_frag_struct *frag;
3071 	struct i40e_tx_buffer *tx_bi;
3072 	struct i40e_tx_desc *tx_desc;
3073 	u16 i = tx_ring->next_to_use;
3074 	u32 td_tag = 0;
3075 	dma_addr_t dma;
3076 	u16 desc_count = 1;
3077 
3078 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
3079 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
3080 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
3081 			 I40E_TX_FLAGS_VLAN_SHIFT;
3082 	}
3083 
3084 	first->tx_flags = tx_flags;
3085 
3086 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
3087 
3088 	tx_desc = I40E_TX_DESC(tx_ring, i);
3089 	tx_bi = first;
3090 
3091 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
3092 		unsigned int max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3093 
3094 		if (dma_mapping_error(tx_ring->dev, dma))
3095 			goto dma_error;
3096 
3097 		/* record length, and DMA address */
3098 		dma_unmap_len_set(tx_bi, len, size);
3099 		dma_unmap_addr_set(tx_bi, dma, dma);
3100 
3101 		/* align size to end of page */
3102 		max_data += -dma & (I40E_MAX_READ_REQ_SIZE - 1);
3103 		tx_desc->buffer_addr = cpu_to_le64(dma);
3104 
3105 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
3106 			tx_desc->cmd_type_offset_bsz =
3107 				build_ctob(td_cmd, td_offset,
3108 					   max_data, td_tag);
3109 
3110 			tx_desc++;
3111 			i++;
3112 			desc_count++;
3113 
3114 			if (i == tx_ring->count) {
3115 				tx_desc = I40E_TX_DESC(tx_ring, 0);
3116 				i = 0;
3117 			}
3118 
3119 			dma += max_data;
3120 			size -= max_data;
3121 
3122 			max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3123 			tx_desc->buffer_addr = cpu_to_le64(dma);
3124 		}
3125 
3126 		if (likely(!data_len))
3127 			break;
3128 
3129 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
3130 							  size, td_tag);
3131 
3132 		tx_desc++;
3133 		i++;
3134 		desc_count++;
3135 
3136 		if (i == tx_ring->count) {
3137 			tx_desc = I40E_TX_DESC(tx_ring, 0);
3138 			i = 0;
3139 		}
3140 
3141 		size = skb_frag_size(frag);
3142 		data_len -= size;
3143 
3144 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
3145 				       DMA_TO_DEVICE);
3146 
3147 		tx_bi = &tx_ring->tx_bi[i];
3148 	}
3149 
3150 	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
3151 
3152 	i++;
3153 	if (i == tx_ring->count)
3154 		i = 0;
3155 
3156 	tx_ring->next_to_use = i;
3157 
3158 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
3159 
3160 	/* write last descriptor with EOP bit */
3161 	td_cmd |= I40E_TX_DESC_CMD_EOP;
3162 
3163 	/* We can OR these values together as they both are checked against
3164 	 * 4 below and at this point desc_count will be used as a boolean value
3165 	 * after this if/else block.
3166 	 */
3167 	desc_count |= ++tx_ring->packet_stride;
3168 
3169 	/* Algorithm to optimize tail and RS bit setting:
3170 	 * if queue is stopped
3171 	 *	mark RS bit
3172 	 *	reset packet counter
3173 	 * else if xmit_more is supported and is true
3174 	 *	advance packet counter to 4
3175 	 *	reset desc_count to 0
3176 	 *
3177 	 * if desc_count >= 4
3178 	 *	mark RS bit
3179 	 *	reset packet counter
3180 	 * if desc_count > 0
3181 	 *	update tail
3182 	 *
3183 	 * Note: If there are less than 4 descriptors
3184 	 * pending and interrupts were disabled the service task will
3185 	 * trigger a force WB.
3186 	 */
3187 	if (netif_xmit_stopped(txring_txq(tx_ring))) {
3188 		goto do_rs;
3189 	} else if (skb->xmit_more) {
3190 		/* set stride to arm on next packet and reset desc_count */
3191 		tx_ring->packet_stride = WB_STRIDE;
3192 		desc_count = 0;
3193 	} else if (desc_count >= WB_STRIDE) {
3194 do_rs:
3195 		/* write last descriptor with RS bit set */
3196 		td_cmd |= I40E_TX_DESC_CMD_RS;
3197 		tx_ring->packet_stride = 0;
3198 	}
3199 
3200 	tx_desc->cmd_type_offset_bsz =
3201 			build_ctob(td_cmd, td_offset, size, td_tag);
3202 
3203 	/* Force memory writes to complete before letting h/w know there
3204 	 * are new descriptors to fetch.
3205 	 *
3206 	 * We also use this memory barrier to make certain all of the
3207 	 * status bits have been updated before next_to_watch is written.
3208 	 */
3209 	wmb();
3210 
3211 	/* set next_to_watch value indicating a packet is present */
3212 	first->next_to_watch = tx_desc;
3213 
3214 	/* notify HW of packet */
3215 	if (desc_count) {
3216 		writel(i, tx_ring->tail);
3217 
3218 		/* we need this if more than one processor can write to our tail
3219 		 * at a time, it synchronizes IO on IA64/Altix systems
3220 		 */
3221 		mmiowb();
3222 	}
3223 
3224 	return 0;
3225 
3226 dma_error:
3227 	dev_info(tx_ring->dev, "TX DMA map failed\n");
3228 
3229 	/* clear dma mappings for failed tx_bi map */
3230 	for (;;) {
3231 		tx_bi = &tx_ring->tx_bi[i];
3232 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
3233 		if (tx_bi == first)
3234 			break;
3235 		if (i == 0)
3236 			i = tx_ring->count;
3237 		i--;
3238 	}
3239 
3240 	tx_ring->next_to_use = i;
3241 
3242 	return -1;
3243 }
3244 
3245 /**
3246  * i40e_xmit_xdp_ring - transmits an XDP buffer to an XDP Tx ring
3247  * @xdp: data to transmit
3248  * @xdp_ring: XDP Tx ring
3249  **/
3250 static int i40e_xmit_xdp_ring(struct xdp_buff *xdp,
3251 			      struct i40e_ring *xdp_ring)
3252 {
3253 	u32 size = xdp->data_end - xdp->data;
3254 	u16 i = xdp_ring->next_to_use;
3255 	struct i40e_tx_buffer *tx_bi;
3256 	struct i40e_tx_desc *tx_desc;
3257 	dma_addr_t dma;
3258 
3259 	if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
3260 		xdp_ring->tx_stats.tx_busy++;
3261 		return I40E_XDP_CONSUMED;
3262 	}
3263 
3264 	dma = dma_map_single(xdp_ring->dev, xdp->data, size, DMA_TO_DEVICE);
3265 	if (dma_mapping_error(xdp_ring->dev, dma))
3266 		return I40E_XDP_CONSUMED;
3267 
3268 	tx_bi = &xdp_ring->tx_bi[i];
3269 	tx_bi->bytecount = size;
3270 	tx_bi->gso_segs = 1;
3271 	tx_bi->raw_buf = xdp->data;
3272 
3273 	/* record length, and DMA address */
3274 	dma_unmap_len_set(tx_bi, len, size);
3275 	dma_unmap_addr_set(tx_bi, dma, dma);
3276 
3277 	tx_desc = I40E_TX_DESC(xdp_ring, i);
3278 	tx_desc->buffer_addr = cpu_to_le64(dma);
3279 	tx_desc->cmd_type_offset_bsz = build_ctob(I40E_TX_DESC_CMD_ICRC
3280 						  | I40E_TXD_CMD,
3281 						  0, size, 0);
3282 
3283 	/* Make certain all of the status bits have been updated
3284 	 * before next_to_watch is written.
3285 	 */
3286 	smp_wmb();
3287 
3288 	i++;
3289 	if (i == xdp_ring->count)
3290 		i = 0;
3291 
3292 	tx_bi->next_to_watch = tx_desc;
3293 	xdp_ring->next_to_use = i;
3294 
3295 	return I40E_XDP_TX;
3296 }
3297 
3298 /**
3299  * i40e_xmit_frame_ring - Sends buffer on Tx ring
3300  * @skb:     send buffer
3301  * @tx_ring: ring to send buffer on
3302  *
3303  * Returns NETDEV_TX_OK if sent, else an error code
3304  **/
3305 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
3306 					struct i40e_ring *tx_ring)
3307 {
3308 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
3309 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
3310 	struct i40e_tx_buffer *first;
3311 	u32 td_offset = 0;
3312 	u32 tx_flags = 0;
3313 	__be16 protocol;
3314 	u32 td_cmd = 0;
3315 	u8 hdr_len = 0;
3316 	int tso, count;
3317 	int tsyn;
3318 
3319 	/* prefetch the data, we'll need it later */
3320 	prefetch(skb->data);
3321 
3322 	i40e_trace(xmit_frame_ring, skb, tx_ring);
3323 
3324 	count = i40e_xmit_descriptor_count(skb);
3325 	if (i40e_chk_linearize(skb, count)) {
3326 		if (__skb_linearize(skb)) {
3327 			dev_kfree_skb_any(skb);
3328 			return NETDEV_TX_OK;
3329 		}
3330 		count = i40e_txd_use_count(skb->len);
3331 		tx_ring->tx_stats.tx_linearize++;
3332 	}
3333 
3334 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
3335 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
3336 	 *       + 4 desc gap to avoid the cache line where head is,
3337 	 *       + 1 desc for context descriptor,
3338 	 * otherwise try next time
3339 	 */
3340 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
3341 		tx_ring->tx_stats.tx_busy++;
3342 		return NETDEV_TX_BUSY;
3343 	}
3344 
3345 	/* record the location of the first descriptor for this packet */
3346 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
3347 	first->skb = skb;
3348 	first->bytecount = skb->len;
3349 	first->gso_segs = 1;
3350 
3351 	/* prepare the xmit flags */
3352 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
3353 		goto out_drop;
3354 
3355 	/* obtain protocol of skb */
3356 	protocol = vlan_get_protocol(skb);
3357 
3358 	/* setup IPv4/IPv6 offloads */
3359 	if (protocol == htons(ETH_P_IP))
3360 		tx_flags |= I40E_TX_FLAGS_IPV4;
3361 	else if (protocol == htons(ETH_P_IPV6))
3362 		tx_flags |= I40E_TX_FLAGS_IPV6;
3363 
3364 	tso = i40e_tso(first, &hdr_len, &cd_type_cmd_tso_mss);
3365 
3366 	if (tso < 0)
3367 		goto out_drop;
3368 	else if (tso)
3369 		tx_flags |= I40E_TX_FLAGS_TSO;
3370 
3371 	/* Always offload the checksum, since it's in the data descriptor */
3372 	tso = i40e_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset,
3373 				  tx_ring, &cd_tunneling);
3374 	if (tso < 0)
3375 		goto out_drop;
3376 
3377 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
3378 
3379 	if (tsyn)
3380 		tx_flags |= I40E_TX_FLAGS_TSYN;
3381 
3382 	skb_tx_timestamp(skb);
3383 
3384 	/* always enable CRC insertion offload */
3385 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
3386 
3387 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
3388 			   cd_tunneling, cd_l2tag2);
3389 
3390 	/* Add Flow Director ATR if it's enabled.
3391 	 *
3392 	 * NOTE: this must always be directly before the data descriptor.
3393 	 */
3394 	i40e_atr(tx_ring, skb, tx_flags);
3395 
3396 	if (i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
3397 			td_cmd, td_offset))
3398 		goto cleanup_tx_tstamp;
3399 
3400 	return NETDEV_TX_OK;
3401 
3402 out_drop:
3403 	i40e_trace(xmit_frame_ring_drop, first->skb, tx_ring);
3404 	dev_kfree_skb_any(first->skb);
3405 	first->skb = NULL;
3406 cleanup_tx_tstamp:
3407 	if (unlikely(tx_flags & I40E_TX_FLAGS_TSYN)) {
3408 		struct i40e_pf *pf = i40e_netdev_to_pf(tx_ring->netdev);
3409 
3410 		dev_kfree_skb_any(pf->ptp_tx_skb);
3411 		pf->ptp_tx_skb = NULL;
3412 		clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, pf->state);
3413 	}
3414 
3415 	return NETDEV_TX_OK;
3416 }
3417 
3418 /**
3419  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
3420  * @skb:    send buffer
3421  * @netdev: network interface device structure
3422  *
3423  * Returns NETDEV_TX_OK if sent, else an error code
3424  **/
3425 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
3426 {
3427 	struct i40e_netdev_priv *np = netdev_priv(netdev);
3428 	struct i40e_vsi *vsi = np->vsi;
3429 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
3430 
3431 	/* hardware can't handle really short frames, hardware padding works
3432 	 * beyond this point
3433 	 */
3434 	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
3435 		return NETDEV_TX_OK;
3436 
3437 	return i40e_xmit_frame_ring(skb, tx_ring);
3438 }
3439