1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 - 2014 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 "i40e.h"
29 #include "i40e_prototype.h"
30 
31 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
32 				u32 td_tag)
33 {
34 	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
35 			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
36 			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
37 			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
38 			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
39 }
40 
41 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
42 #define I40E_FD_CLEAN_DELAY 10
43 /**
44  * i40e_program_fdir_filter - Program a Flow Director filter
45  * @fdir_data: Packet data that will be filter parameters
46  * @raw_packet: the pre-allocated packet buffer for FDir
47  * @pf: The pf pointer
48  * @add: True for add/update, False for remove
49  **/
50 int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data, u8 *raw_packet,
51 			     struct i40e_pf *pf, bool add)
52 {
53 	struct i40e_filter_program_desc *fdir_desc;
54 	struct i40e_tx_buffer *tx_buf, *first;
55 	struct i40e_tx_desc *tx_desc;
56 	struct i40e_ring *tx_ring;
57 	unsigned int fpt, dcc;
58 	struct i40e_vsi *vsi;
59 	struct device *dev;
60 	dma_addr_t dma;
61 	u32 td_cmd = 0;
62 	u16 delay = 0;
63 	u16 i;
64 
65 	/* find existing FDIR VSI */
66 	vsi = NULL;
67 	for (i = 0; i < pf->num_alloc_vsi; i++)
68 		if (pf->vsi[i] && pf->vsi[i]->type == I40E_VSI_FDIR)
69 			vsi = pf->vsi[i];
70 	if (!vsi)
71 		return -ENOENT;
72 
73 	tx_ring = vsi->tx_rings[0];
74 	dev = tx_ring->dev;
75 
76 	/* we need two descriptors to add/del a filter and we can wait */
77 	do {
78 		if (I40E_DESC_UNUSED(tx_ring) > 1)
79 			break;
80 		msleep_interruptible(1);
81 		delay++;
82 	} while (delay < I40E_FD_CLEAN_DELAY);
83 
84 	if (!(I40E_DESC_UNUSED(tx_ring) > 1))
85 		return -EAGAIN;
86 
87 	dma = dma_map_single(dev, raw_packet,
88 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
89 	if (dma_mapping_error(dev, dma))
90 		goto dma_fail;
91 
92 	/* grab the next descriptor */
93 	i = tx_ring->next_to_use;
94 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
95 	first = &tx_ring->tx_bi[i];
96 	memset(first, 0, sizeof(struct i40e_tx_buffer));
97 
98 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
99 
100 	fpt = (fdir_data->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
101 	      I40E_TXD_FLTR_QW0_QINDEX_MASK;
102 
103 	fpt |= (fdir_data->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT) &
104 	       I40E_TXD_FLTR_QW0_FLEXOFF_MASK;
105 
106 	fpt |= (fdir_data->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) &
107 	       I40E_TXD_FLTR_QW0_PCTYPE_MASK;
108 
109 	/* Use LAN VSI Id if not programmed by user */
110 	if (fdir_data->dest_vsi == 0)
111 		fpt |= (pf->vsi[pf->lan_vsi]->id) <<
112 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
113 	else
114 		fpt |= ((u32)fdir_data->dest_vsi <<
115 			I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT) &
116 		       I40E_TXD_FLTR_QW0_DEST_VSI_MASK;
117 
118 	dcc = I40E_TX_DESC_DTYPE_FILTER_PROG;
119 
120 	if (add)
121 		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
122 		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
123 	else
124 		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
125 		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
126 
127 	dcc |= (fdir_data->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT) &
128 	       I40E_TXD_FLTR_QW1_DEST_MASK;
129 
130 	dcc |= (fdir_data->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT) &
131 	       I40E_TXD_FLTR_QW1_FD_STATUS_MASK;
132 
133 	if (fdir_data->cnt_index != 0) {
134 		dcc |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
135 		dcc |= ((u32)fdir_data->cnt_index <<
136 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
137 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
138 	}
139 
140 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(fpt);
141 	fdir_desc->rsvd = cpu_to_le32(0);
142 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dcc);
143 	fdir_desc->fd_id = cpu_to_le32(fdir_data->fd_id);
144 
145 	/* Now program a dummy descriptor */
146 	i = tx_ring->next_to_use;
147 	tx_desc = I40E_TX_DESC(tx_ring, i);
148 	tx_buf = &tx_ring->tx_bi[i];
149 
150 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
151 
152 	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
153 
154 	/* record length, and DMA address */
155 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
156 	dma_unmap_addr_set(tx_buf, dma, dma);
157 
158 	tx_desc->buffer_addr = cpu_to_le64(dma);
159 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
160 
161 	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
162 	tx_buf->raw_buf = (void *)raw_packet;
163 
164 	tx_desc->cmd_type_offset_bsz =
165 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
166 
167 	/* set the timestamp */
168 	tx_buf->time_stamp = jiffies;
169 
170 	/* Force memory writes to complete before letting h/w
171 	 * know there are new descriptors to fetch.
172 	 */
173 	wmb();
174 
175 	/* Mark the data descriptor to be watched */
176 	first->next_to_watch = tx_desc;
177 
178 	writel(tx_ring->next_to_use, tx_ring->tail);
179 	return 0;
180 
181 dma_fail:
182 	return -1;
183 }
184 
185 #define IP_HEADER_OFFSET 14
186 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
187 /**
188  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
189  * @vsi: pointer to the targeted VSI
190  * @fd_data: the flow director data required for the FDir descriptor
191  * @add: true adds a filter, false removes it
192  *
193  * Returns 0 if the filters were successfully added or removed
194  **/
195 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
196 				   struct i40e_fdir_filter *fd_data,
197 				   bool add)
198 {
199 	struct i40e_pf *pf = vsi->back;
200 	struct udphdr *udp;
201 	struct iphdr *ip;
202 	bool err = false;
203 	u8 *raw_packet;
204 	int ret;
205 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
206 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
207 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
208 
209 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
210 	if (!raw_packet)
211 		return -ENOMEM;
212 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
213 
214 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
215 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
216 	      + sizeof(struct iphdr));
217 
218 	ip->daddr = fd_data->dst_ip[0];
219 	udp->dest = fd_data->dst_port;
220 	ip->saddr = fd_data->src_ip[0];
221 	udp->source = fd_data->src_port;
222 
223 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
224 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
225 	if (ret) {
226 		dev_info(&pf->pdev->dev,
227 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
228 			 fd_data->pctype, fd_data->fd_id, ret);
229 		err = true;
230 	} else {
231 		if (add)
232 			dev_info(&pf->pdev->dev,
233 				 "Filter OK for PCTYPE %d loc = %d\n",
234 				 fd_data->pctype, fd_data->fd_id);
235 		else
236 			dev_info(&pf->pdev->dev,
237 				 "Filter deleted for PCTYPE %d loc = %d\n",
238 				 fd_data->pctype, fd_data->fd_id);
239 	}
240 	return err ? -EOPNOTSUPP : 0;
241 }
242 
243 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
244 /**
245  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
246  * @vsi: pointer to the targeted VSI
247  * @fd_data: the flow director data required for the FDir descriptor
248  * @add: true adds a filter, false removes it
249  *
250  * Returns 0 if the filters were successfully added or removed
251  **/
252 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
253 				   struct i40e_fdir_filter *fd_data,
254 				   bool add)
255 {
256 	struct i40e_pf *pf = vsi->back;
257 	struct tcphdr *tcp;
258 	struct iphdr *ip;
259 	bool err = false;
260 	u8 *raw_packet;
261 	int ret;
262 	/* Dummy packet */
263 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
264 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
265 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
266 		0x0, 0x72, 0, 0, 0, 0};
267 
268 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
269 	if (!raw_packet)
270 		return -ENOMEM;
271 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
272 
273 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
274 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
275 	      + sizeof(struct iphdr));
276 
277 	ip->daddr = fd_data->dst_ip[0];
278 	tcp->dest = fd_data->dst_port;
279 	ip->saddr = fd_data->src_ip[0];
280 	tcp->source = fd_data->src_port;
281 
282 	if (add) {
283 		pf->fd_tcp_rule++;
284 		if (pf->flags & I40E_FLAG_FD_ATR_ENABLED) {
285 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
286 			pf->flags &= ~I40E_FLAG_FD_ATR_ENABLED;
287 		}
288 	} else {
289 		pf->fd_tcp_rule = (pf->fd_tcp_rule > 0) ?
290 				  (pf->fd_tcp_rule - 1) : 0;
291 		if (pf->fd_tcp_rule == 0) {
292 			pf->flags |= I40E_FLAG_FD_ATR_ENABLED;
293 			dev_info(&pf->pdev->dev, "ATR re-enabled due to no sideband TCP/IPv4 rules\n");
294 		}
295 	}
296 
297 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
298 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
299 
300 	if (ret) {
301 		dev_info(&pf->pdev->dev,
302 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
303 			 fd_data->pctype, fd_data->fd_id, ret);
304 		err = true;
305 	} else {
306 		if (add)
307 			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
308 				 fd_data->pctype, fd_data->fd_id);
309 		else
310 			dev_info(&pf->pdev->dev,
311 				 "Filter deleted for PCTYPE %d loc = %d\n",
312 				 fd_data->pctype, fd_data->fd_id);
313 	}
314 
315 	return err ? -EOPNOTSUPP : 0;
316 }
317 
318 /**
319  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
320  * a specific flow spec
321  * @vsi: pointer to the targeted VSI
322  * @fd_data: the flow director data required for the FDir descriptor
323  * @add: true adds a filter, false removes it
324  *
325  * Always returns -EOPNOTSUPP
326  **/
327 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
328 				    struct i40e_fdir_filter *fd_data,
329 				    bool add)
330 {
331 	return -EOPNOTSUPP;
332 }
333 
334 #define I40E_IP_DUMMY_PACKET_LEN 34
335 /**
336  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
337  * a specific flow spec
338  * @vsi: pointer to the targeted VSI
339  * @fd_data: the flow director data required for the FDir descriptor
340  * @add: true adds a filter, false removes it
341  *
342  * Returns 0 if the filters were successfully added or removed
343  **/
344 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
345 				  struct i40e_fdir_filter *fd_data,
346 				  bool add)
347 {
348 	struct i40e_pf *pf = vsi->back;
349 	struct iphdr *ip;
350 	bool err = false;
351 	u8 *raw_packet;
352 	int ret;
353 	int i;
354 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
355 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
356 		0, 0, 0, 0};
357 
358 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
359 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
360 		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
361 		if (!raw_packet)
362 			return -ENOMEM;
363 		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
364 		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
365 
366 		ip->saddr = fd_data->src_ip[0];
367 		ip->daddr = fd_data->dst_ip[0];
368 		ip->protocol = 0;
369 
370 		fd_data->pctype = i;
371 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
372 
373 		if (ret) {
374 			dev_info(&pf->pdev->dev,
375 				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
376 				 fd_data->pctype, fd_data->fd_id, ret);
377 			err = true;
378 		} else {
379 			if (add)
380 				dev_info(&pf->pdev->dev,
381 					 "Filter OK for PCTYPE %d loc = %d\n",
382 					 fd_data->pctype, fd_data->fd_id);
383 			else
384 				dev_info(&pf->pdev->dev,
385 					 "Filter deleted for PCTYPE %d loc = %d\n",
386 					 fd_data->pctype, fd_data->fd_id);
387 		}
388 	}
389 
390 	return err ? -EOPNOTSUPP : 0;
391 }
392 
393 /**
394  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
395  * @vsi: pointer to the targeted VSI
396  * @cmd: command to get or set RX flow classification rules
397  * @add: true adds a filter, false removes it
398  *
399  **/
400 int i40e_add_del_fdir(struct i40e_vsi *vsi,
401 		      struct i40e_fdir_filter *input, bool add)
402 {
403 	struct i40e_pf *pf = vsi->back;
404 	int ret;
405 
406 	switch (input->flow_type & ~FLOW_EXT) {
407 	case TCP_V4_FLOW:
408 		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
409 		break;
410 	case UDP_V4_FLOW:
411 		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
412 		break;
413 	case SCTP_V4_FLOW:
414 		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
415 		break;
416 	case IPV4_FLOW:
417 		ret = i40e_add_del_fdir_ipv4(vsi, input, add);
418 		break;
419 	case IP_USER_FLOW:
420 		switch (input->ip4_proto) {
421 		case IPPROTO_TCP:
422 			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
423 			break;
424 		case IPPROTO_UDP:
425 			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
426 			break;
427 		case IPPROTO_SCTP:
428 			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
429 			break;
430 		default:
431 			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
432 			break;
433 		}
434 		break;
435 	default:
436 		dev_info(&pf->pdev->dev, "Could not specify spec type %d\n",
437 			 input->flow_type);
438 		ret = -EINVAL;
439 	}
440 
441 	/* The buffer allocated here is freed by the i40e_clean_tx_ring() */
442 	return ret;
443 }
444 
445 /**
446  * i40e_fd_handle_status - check the Programming Status for FD
447  * @rx_ring: the Rx ring for this descriptor
448  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
449  * @prog_id: the id originally used for programming
450  *
451  * This is used to verify if the FD programming or invalidation
452  * requested by SW to the HW is successful or not and take actions accordingly.
453  **/
454 static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
455 				  union i40e_rx_desc *rx_desc, u8 prog_id)
456 {
457 	struct i40e_pf *pf = rx_ring->vsi->back;
458 	struct pci_dev *pdev = pf->pdev;
459 	u32 fcnt_prog, fcnt_avail;
460 	u32 error;
461 	u64 qw;
462 
463 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
464 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
465 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
466 
467 	if (error == (0x1 << I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
468 		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
469 		    (I40E_DEBUG_FD & pf->hw.debug_mask))
470 			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
471 				 rx_desc->wb.qword0.hi_dword.fd_id);
472 
473 		pf->fd_add_err++;
474 		/* store the current atr filter count */
475 		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
476 
477 		/* filter programming failed most likely due to table full */
478 		fcnt_prog = i40e_get_cur_guaranteed_fd_count(pf);
479 		fcnt_avail = pf->fdir_pf_filter_count;
480 		/* If ATR is running fcnt_prog can quickly change,
481 		 * if we are very close to full, it makes sense to disable
482 		 * FD ATR/SB and then re-enable it when there is room.
483 		 */
484 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
485 			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
486 			    !(pf->auto_disable_flags &
487 				     I40E_FLAG_FD_SB_ENABLED)) {
488 				dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
489 				pf->auto_disable_flags |=
490 							I40E_FLAG_FD_SB_ENABLED;
491 			}
492 		} else {
493 			dev_info(&pdev->dev,
494 				"FD filter programming failed due to incorrect filter parameters\n");
495 		}
496 	} else if (error ==
497 			  (0x1 << I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
498 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
499 			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
500 				 rx_desc->wb.qword0.hi_dword.fd_id);
501 	}
502 }
503 
504 /**
505  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
506  * @ring:      the ring that owns the buffer
507  * @tx_buffer: the buffer to free
508  **/
509 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
510 					    struct i40e_tx_buffer *tx_buffer)
511 {
512 	if (tx_buffer->skb) {
513 		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
514 			kfree(tx_buffer->raw_buf);
515 		else
516 			dev_kfree_skb_any(tx_buffer->skb);
517 
518 		if (dma_unmap_len(tx_buffer, len))
519 			dma_unmap_single(ring->dev,
520 					 dma_unmap_addr(tx_buffer, dma),
521 					 dma_unmap_len(tx_buffer, len),
522 					 DMA_TO_DEVICE);
523 	} else if (dma_unmap_len(tx_buffer, len)) {
524 		dma_unmap_page(ring->dev,
525 			       dma_unmap_addr(tx_buffer, dma),
526 			       dma_unmap_len(tx_buffer, len),
527 			       DMA_TO_DEVICE);
528 	}
529 	tx_buffer->next_to_watch = NULL;
530 	tx_buffer->skb = NULL;
531 	dma_unmap_len_set(tx_buffer, len, 0);
532 	/* tx_buffer must be completely set up in the transmit path */
533 }
534 
535 /**
536  * i40e_clean_tx_ring - Free any empty Tx buffers
537  * @tx_ring: ring to be cleaned
538  **/
539 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
540 {
541 	unsigned long bi_size;
542 	u16 i;
543 
544 	/* ring already cleared, nothing to do */
545 	if (!tx_ring->tx_bi)
546 		return;
547 
548 	/* Free all the Tx ring sk_buffs */
549 	for (i = 0; i < tx_ring->count; i++)
550 		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
551 
552 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
553 	memset(tx_ring->tx_bi, 0, bi_size);
554 
555 	/* Zero out the descriptor ring */
556 	memset(tx_ring->desc, 0, tx_ring->size);
557 
558 	tx_ring->next_to_use = 0;
559 	tx_ring->next_to_clean = 0;
560 
561 	if (!tx_ring->netdev)
562 		return;
563 
564 	/* cleanup Tx queue statistics */
565 	netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
566 						  tx_ring->queue_index));
567 }
568 
569 /**
570  * i40e_free_tx_resources - Free Tx resources per queue
571  * @tx_ring: Tx descriptor ring for a specific queue
572  *
573  * Free all transmit software resources
574  **/
575 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
576 {
577 	i40e_clean_tx_ring(tx_ring);
578 	kfree(tx_ring->tx_bi);
579 	tx_ring->tx_bi = NULL;
580 
581 	if (tx_ring->desc) {
582 		dma_free_coherent(tx_ring->dev, tx_ring->size,
583 				  tx_ring->desc, tx_ring->dma);
584 		tx_ring->desc = NULL;
585 	}
586 }
587 
588 /**
589  * i40e_get_tx_pending - how many tx descriptors not processed
590  * @tx_ring: the ring of descriptors
591  *
592  * Since there is no access to the ring head register
593  * in XL710, we need to use our local copies
594  **/
595 static u32 i40e_get_tx_pending(struct i40e_ring *ring)
596 {
597 	u32 ntu = ((ring->next_to_clean <= ring->next_to_use)
598 			? ring->next_to_use
599 			: ring->next_to_use + ring->count);
600 	return ntu - ring->next_to_clean;
601 }
602 
603 /**
604  * i40e_check_tx_hang - Is there a hang in the Tx queue
605  * @tx_ring: the ring of descriptors
606  **/
607 static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
608 {
609 	u32 tx_pending = i40e_get_tx_pending(tx_ring);
610 	struct i40e_pf *pf = tx_ring->vsi->back;
611 	bool ret = false;
612 
613 	clear_check_for_tx_hang(tx_ring);
614 
615 	/* Check for a hung queue, but be thorough. This verifies
616 	 * that a transmit has been completed since the previous
617 	 * check AND there is at least one packet pending. The
618 	 * ARMED bit is set to indicate a potential hang. The
619 	 * bit is cleared if a pause frame is received to remove
620 	 * false hang detection due to PFC or 802.3x frames. By
621 	 * requiring this to fail twice we avoid races with
622 	 * PFC clearing the ARMED bit and conditions where we
623 	 * run the check_tx_hang logic with a transmit completion
624 	 * pending but without time to complete it yet.
625 	 */
626 	if ((tx_ring->tx_stats.tx_done_old == tx_ring->stats.packets) &&
627 	    (tx_pending >= I40E_MIN_DESC_PENDING)) {
628 		/* make sure it is true for two checks in a row */
629 		ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
630 				       &tx_ring->state);
631 	} else if ((tx_ring->tx_stats.tx_done_old == tx_ring->stats.packets) &&
632 		   (tx_pending < I40E_MIN_DESC_PENDING) &&
633 		   (tx_pending > 0)) {
634 		if (I40E_DEBUG_FLOW & pf->hw.debug_mask)
635 			dev_info(tx_ring->dev, "HW needs some more descs to do a cacheline flush. tx_pending %d, queue %d",
636 				 tx_pending, tx_ring->queue_index);
637 		pf->tx_sluggish_count++;
638 	} else {
639 		/* update completed stats and disarm the hang check */
640 		tx_ring->tx_stats.tx_done_old = tx_ring->stats.packets;
641 		clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
642 	}
643 
644 	return ret;
645 }
646 
647 /**
648  * i40e_get_head - Retrieve head from head writeback
649  * @tx_ring:  tx ring to fetch head of
650  *
651  * Returns value of Tx ring head based on value stored
652  * in head write-back location
653  **/
654 static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
655 {
656 	void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
657 
658 	return le32_to_cpu(*(volatile __le32 *)head);
659 }
660 
661 #define WB_STRIDE 0x3
662 
663 /**
664  * i40e_clean_tx_irq - Reclaim resources after transmit completes
665  * @tx_ring:  tx ring to clean
666  * @budget:   how many cleans we're allowed
667  *
668  * Returns true if there's any budget left (e.g. the clean is finished)
669  **/
670 static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
671 {
672 	u16 i = tx_ring->next_to_clean;
673 	struct i40e_tx_buffer *tx_buf;
674 	struct i40e_tx_desc *tx_head;
675 	struct i40e_tx_desc *tx_desc;
676 	unsigned int total_packets = 0;
677 	unsigned int total_bytes = 0;
678 
679 	tx_buf = &tx_ring->tx_bi[i];
680 	tx_desc = I40E_TX_DESC(tx_ring, i);
681 	i -= tx_ring->count;
682 
683 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
684 
685 	do {
686 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
687 
688 		/* if next_to_watch is not set then there is no work pending */
689 		if (!eop_desc)
690 			break;
691 
692 		/* prevent any other reads prior to eop_desc */
693 		read_barrier_depends();
694 
695 		/* we have caught up to head, no work left to do */
696 		if (tx_head == tx_desc)
697 			break;
698 
699 		/* clear next_to_watch to prevent false hangs */
700 		tx_buf->next_to_watch = NULL;
701 
702 		/* update the statistics for this packet */
703 		total_bytes += tx_buf->bytecount;
704 		total_packets += tx_buf->gso_segs;
705 
706 		/* free the skb */
707 		dev_consume_skb_any(tx_buf->skb);
708 
709 		/* unmap skb header data */
710 		dma_unmap_single(tx_ring->dev,
711 				 dma_unmap_addr(tx_buf, dma),
712 				 dma_unmap_len(tx_buf, len),
713 				 DMA_TO_DEVICE);
714 
715 		/* clear tx_buffer data */
716 		tx_buf->skb = NULL;
717 		dma_unmap_len_set(tx_buf, len, 0);
718 
719 		/* unmap remaining buffers */
720 		while (tx_desc != eop_desc) {
721 
722 			tx_buf++;
723 			tx_desc++;
724 			i++;
725 			if (unlikely(!i)) {
726 				i -= tx_ring->count;
727 				tx_buf = tx_ring->tx_bi;
728 				tx_desc = I40E_TX_DESC(tx_ring, 0);
729 			}
730 
731 			/* unmap any remaining paged data */
732 			if (dma_unmap_len(tx_buf, len)) {
733 				dma_unmap_page(tx_ring->dev,
734 					       dma_unmap_addr(tx_buf, dma),
735 					       dma_unmap_len(tx_buf, len),
736 					       DMA_TO_DEVICE);
737 				dma_unmap_len_set(tx_buf, len, 0);
738 			}
739 		}
740 
741 		/* move us one more past the eop_desc for start of next pkt */
742 		tx_buf++;
743 		tx_desc++;
744 		i++;
745 		if (unlikely(!i)) {
746 			i -= tx_ring->count;
747 			tx_buf = tx_ring->tx_bi;
748 			tx_desc = I40E_TX_DESC(tx_ring, 0);
749 		}
750 
751 		/* update budget accounting */
752 		budget--;
753 	} while (likely(budget));
754 
755 	i += tx_ring->count;
756 	tx_ring->next_to_clean = i;
757 	u64_stats_update_begin(&tx_ring->syncp);
758 	tx_ring->stats.bytes += total_bytes;
759 	tx_ring->stats.packets += total_packets;
760 	u64_stats_update_end(&tx_ring->syncp);
761 	tx_ring->q_vector->tx.total_bytes += total_bytes;
762 	tx_ring->q_vector->tx.total_packets += total_packets;
763 
764 	/* check to see if there are any non-cache aligned descriptors
765 	 * waiting to be written back, and kick the hardware to force
766 	 * them to be written back in case of napi polling
767 	 */
768 	if (budget &&
769 	    !((i & WB_STRIDE) == WB_STRIDE) &&
770 	    !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
771 	    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
772 		tx_ring->arm_wb = true;
773 	else
774 		tx_ring->arm_wb = false;
775 
776 	if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
777 		/* schedule immediate reset if we believe we hung */
778 		dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
779 			 "  VSI                  <%d>\n"
780 			 "  Tx Queue             <%d>\n"
781 			 "  next_to_use          <%x>\n"
782 			 "  next_to_clean        <%x>\n",
783 			 tx_ring->vsi->seid,
784 			 tx_ring->queue_index,
785 			 tx_ring->next_to_use, i);
786 		dev_info(tx_ring->dev, "tx_bi[next_to_clean]\n"
787 			 "  time_stamp           <%lx>\n"
788 			 "  jiffies              <%lx>\n",
789 			 tx_ring->tx_bi[i].time_stamp, jiffies);
790 
791 		netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
792 
793 		dev_info(tx_ring->dev,
794 			 "tx hang detected on queue %d, reset requested\n",
795 			 tx_ring->queue_index);
796 
797 		/* do not fire the reset immediately, wait for the stack to
798 		 * decide we are truly stuck, also prevents every queue from
799 		 * simultaneously requesting a reset
800 		 */
801 
802 		/* the adapter is about to reset, no point in enabling polling */
803 		budget = 1;
804 	}
805 
806 	netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
807 						      tx_ring->queue_index),
808 				  total_packets, total_bytes);
809 
810 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
811 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
812 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
813 		/* Make sure that anybody stopping the queue after this
814 		 * sees the new next_to_clean.
815 		 */
816 		smp_mb();
817 		if (__netif_subqueue_stopped(tx_ring->netdev,
818 					     tx_ring->queue_index) &&
819 		   !test_bit(__I40E_DOWN, &tx_ring->vsi->state)) {
820 			netif_wake_subqueue(tx_ring->netdev,
821 					    tx_ring->queue_index);
822 			++tx_ring->tx_stats.restart_queue;
823 		}
824 	}
825 
826 	return !!budget;
827 }
828 
829 /**
830  * i40e_force_wb - Arm hardware to do a wb on noncache aligned descriptors
831  * @vsi: the VSI we care about
832  * @q_vector: the vector  on which to force writeback
833  *
834  **/
835 static void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
836 {
837 	u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
838 		  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
839 		  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
840 		  /* allow 00 to be written to the index */
841 
842 	wr32(&vsi->back->hw,
843 	     I40E_PFINT_DYN_CTLN(q_vector->v_idx + vsi->base_vector - 1),
844 	     val);
845 }
846 
847 /**
848  * i40e_set_new_dynamic_itr - Find new ITR level
849  * @rc: structure containing ring performance data
850  *
851  * Stores a new ITR value based on packets and byte counts during
852  * the last interrupt.  The advantage of per interrupt computation
853  * is faster updates and more accurate ITR for the current traffic
854  * pattern.  Constants in this function were computed based on
855  * theoretical maximum wire speed and thresholds were set based on
856  * testing data as well as attempting to minimize response time
857  * while increasing bulk throughput.
858  **/
859 static void i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
860 {
861 	enum i40e_latency_range new_latency_range = rc->latency_range;
862 	u32 new_itr = rc->itr;
863 	int bytes_per_int;
864 
865 	if (rc->total_packets == 0 || !rc->itr)
866 		return;
867 
868 	/* simple throttlerate management
869 	 *   0-10MB/s   lowest (100000 ints/s)
870 	 *  10-20MB/s   low    (20000 ints/s)
871 	 *  20-1249MB/s bulk   (8000 ints/s)
872 	 */
873 	bytes_per_int = rc->total_bytes / rc->itr;
874 	switch (rc->itr) {
875 	case I40E_LOWEST_LATENCY:
876 		if (bytes_per_int > 10)
877 			new_latency_range = I40E_LOW_LATENCY;
878 		break;
879 	case I40E_LOW_LATENCY:
880 		if (bytes_per_int > 20)
881 			new_latency_range = I40E_BULK_LATENCY;
882 		else if (bytes_per_int <= 10)
883 			new_latency_range = I40E_LOWEST_LATENCY;
884 		break;
885 	case I40E_BULK_LATENCY:
886 		if (bytes_per_int <= 20)
887 			rc->latency_range = I40E_LOW_LATENCY;
888 		break;
889 	}
890 
891 	switch (new_latency_range) {
892 	case I40E_LOWEST_LATENCY:
893 		new_itr = I40E_ITR_100K;
894 		break;
895 	case I40E_LOW_LATENCY:
896 		new_itr = I40E_ITR_20K;
897 		break;
898 	case I40E_BULK_LATENCY:
899 		new_itr = I40E_ITR_8K;
900 		break;
901 	default:
902 		break;
903 	}
904 
905 	if (new_itr != rc->itr) {
906 		/* do an exponential smoothing */
907 		new_itr = (10 * new_itr * rc->itr) /
908 			  ((9 * new_itr) + rc->itr);
909 		rc->itr = new_itr & I40E_MAX_ITR;
910 	}
911 
912 	rc->total_bytes = 0;
913 	rc->total_packets = 0;
914 }
915 
916 /**
917  * i40e_update_dynamic_itr - Adjust ITR based on bytes per int
918  * @q_vector: the vector to adjust
919  **/
920 static void i40e_update_dynamic_itr(struct i40e_q_vector *q_vector)
921 {
922 	u16 vector = q_vector->vsi->base_vector + q_vector->v_idx;
923 	struct i40e_hw *hw = &q_vector->vsi->back->hw;
924 	u32 reg_addr;
925 	u16 old_itr;
926 
927 	reg_addr = I40E_PFINT_ITRN(I40E_RX_ITR, vector - 1);
928 	old_itr = q_vector->rx.itr;
929 	i40e_set_new_dynamic_itr(&q_vector->rx);
930 	if (old_itr != q_vector->rx.itr)
931 		wr32(hw, reg_addr, q_vector->rx.itr);
932 
933 	reg_addr = I40E_PFINT_ITRN(I40E_TX_ITR, vector - 1);
934 	old_itr = q_vector->tx.itr;
935 	i40e_set_new_dynamic_itr(&q_vector->tx);
936 	if (old_itr != q_vector->tx.itr)
937 		wr32(hw, reg_addr, q_vector->tx.itr);
938 }
939 
940 /**
941  * i40e_clean_programming_status - clean the programming status descriptor
942  * @rx_ring: the rx ring that has this descriptor
943  * @rx_desc: the rx descriptor written back by HW
944  *
945  * Flow director should handle FD_FILTER_STATUS to check its filter programming
946  * status being successful or not and take actions accordingly. FCoE should
947  * handle its context/filter programming/invalidation status and take actions.
948  *
949  **/
950 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
951 					  union i40e_rx_desc *rx_desc)
952 {
953 	u64 qw;
954 	u8 id;
955 
956 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
957 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
958 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
959 
960 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
961 		i40e_fd_handle_status(rx_ring, rx_desc, id);
962 #ifdef I40E_FCOE
963 	else if ((id == I40E_RX_PROG_STATUS_DESC_FCOE_CTXT_PROG_STATUS) ||
964 		 (id == I40E_RX_PROG_STATUS_DESC_FCOE_CTXT_INVL_STATUS))
965 		i40e_fcoe_handle_status(rx_ring, rx_desc, id);
966 #endif
967 }
968 
969 /**
970  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
971  * @tx_ring: the tx ring to set up
972  *
973  * Return 0 on success, negative on error
974  **/
975 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
976 {
977 	struct device *dev = tx_ring->dev;
978 	int bi_size;
979 
980 	if (!dev)
981 		return -ENOMEM;
982 
983 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
984 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
985 	if (!tx_ring->tx_bi)
986 		goto err;
987 
988 	/* round up to nearest 4K */
989 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
990 	/* add u32 for head writeback, align after this takes care of
991 	 * guaranteeing this is at least one cache line in size
992 	 */
993 	tx_ring->size += sizeof(u32);
994 	tx_ring->size = ALIGN(tx_ring->size, 4096);
995 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
996 					   &tx_ring->dma, GFP_KERNEL);
997 	if (!tx_ring->desc) {
998 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
999 			 tx_ring->size);
1000 		goto err;
1001 	}
1002 
1003 	tx_ring->next_to_use = 0;
1004 	tx_ring->next_to_clean = 0;
1005 	return 0;
1006 
1007 err:
1008 	kfree(tx_ring->tx_bi);
1009 	tx_ring->tx_bi = NULL;
1010 	return -ENOMEM;
1011 }
1012 
1013 /**
1014  * i40e_clean_rx_ring - Free Rx buffers
1015  * @rx_ring: ring to be cleaned
1016  **/
1017 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1018 {
1019 	struct device *dev = rx_ring->dev;
1020 	struct i40e_rx_buffer *rx_bi;
1021 	unsigned long bi_size;
1022 	u16 i;
1023 
1024 	/* ring already cleared, nothing to do */
1025 	if (!rx_ring->rx_bi)
1026 		return;
1027 
1028 	/* Free all the Rx ring sk_buffs */
1029 	for (i = 0; i < rx_ring->count; i++) {
1030 		rx_bi = &rx_ring->rx_bi[i];
1031 		if (rx_bi->dma) {
1032 			dma_unmap_single(dev,
1033 					 rx_bi->dma,
1034 					 rx_ring->rx_buf_len,
1035 					 DMA_FROM_DEVICE);
1036 			rx_bi->dma = 0;
1037 		}
1038 		if (rx_bi->skb) {
1039 			dev_kfree_skb(rx_bi->skb);
1040 			rx_bi->skb = NULL;
1041 		}
1042 		if (rx_bi->page) {
1043 			if (rx_bi->page_dma) {
1044 				dma_unmap_page(dev,
1045 					       rx_bi->page_dma,
1046 					       PAGE_SIZE / 2,
1047 					       DMA_FROM_DEVICE);
1048 				rx_bi->page_dma = 0;
1049 			}
1050 			__free_page(rx_bi->page);
1051 			rx_bi->page = NULL;
1052 			rx_bi->page_offset = 0;
1053 		}
1054 	}
1055 
1056 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1057 	memset(rx_ring->rx_bi, 0, bi_size);
1058 
1059 	/* Zero out the descriptor ring */
1060 	memset(rx_ring->desc, 0, rx_ring->size);
1061 
1062 	rx_ring->next_to_clean = 0;
1063 	rx_ring->next_to_use = 0;
1064 }
1065 
1066 /**
1067  * i40e_free_rx_resources - Free Rx resources
1068  * @rx_ring: ring to clean the resources from
1069  *
1070  * Free all receive software resources
1071  **/
1072 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1073 {
1074 	i40e_clean_rx_ring(rx_ring);
1075 	kfree(rx_ring->rx_bi);
1076 	rx_ring->rx_bi = NULL;
1077 
1078 	if (rx_ring->desc) {
1079 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1080 				  rx_ring->desc, rx_ring->dma);
1081 		rx_ring->desc = NULL;
1082 	}
1083 }
1084 
1085 /**
1086  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1087  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1088  *
1089  * Returns 0 on success, negative on failure
1090  **/
1091 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1092 {
1093 	struct device *dev = rx_ring->dev;
1094 	int bi_size;
1095 
1096 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1097 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1098 	if (!rx_ring->rx_bi)
1099 		goto err;
1100 
1101 	u64_stats_init(&rx_ring->syncp);
1102 
1103 	/* Round up to nearest 4K */
1104 	rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
1105 		? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
1106 		: rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1107 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1108 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1109 					   &rx_ring->dma, GFP_KERNEL);
1110 
1111 	if (!rx_ring->desc) {
1112 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1113 			 rx_ring->size);
1114 		goto err;
1115 	}
1116 
1117 	rx_ring->next_to_clean = 0;
1118 	rx_ring->next_to_use = 0;
1119 
1120 	return 0;
1121 err:
1122 	kfree(rx_ring->rx_bi);
1123 	rx_ring->rx_bi = NULL;
1124 	return -ENOMEM;
1125 }
1126 
1127 /**
1128  * i40e_release_rx_desc - Store the new tail and head values
1129  * @rx_ring: ring to bump
1130  * @val: new head index
1131  **/
1132 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1133 {
1134 	rx_ring->next_to_use = val;
1135 	/* Force memory writes to complete before letting h/w
1136 	 * know there are new descriptors to fetch.  (Only
1137 	 * applicable for weak-ordered memory model archs,
1138 	 * such as IA-64).
1139 	 */
1140 	wmb();
1141 	writel(val, rx_ring->tail);
1142 }
1143 
1144 /**
1145  * i40e_alloc_rx_buffers - Replace used receive buffers; packet split
1146  * @rx_ring: ring to place buffers on
1147  * @cleaned_count: number of buffers to replace
1148  **/
1149 void i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1150 {
1151 	u16 i = rx_ring->next_to_use;
1152 	union i40e_rx_desc *rx_desc;
1153 	struct i40e_rx_buffer *bi;
1154 	struct sk_buff *skb;
1155 
1156 	/* do nothing if no valid netdev defined */
1157 	if (!rx_ring->netdev || !cleaned_count)
1158 		return;
1159 
1160 	while (cleaned_count--) {
1161 		rx_desc = I40E_RX_DESC(rx_ring, i);
1162 		bi = &rx_ring->rx_bi[i];
1163 		skb = bi->skb;
1164 
1165 		if (!skb) {
1166 			skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
1167 							rx_ring->rx_buf_len);
1168 			if (!skb) {
1169 				rx_ring->rx_stats.alloc_buff_failed++;
1170 				goto no_buffers;
1171 			}
1172 			/* initialize queue mapping */
1173 			skb_record_rx_queue(skb, rx_ring->queue_index);
1174 			bi->skb = skb;
1175 		}
1176 
1177 		if (!bi->dma) {
1178 			bi->dma = dma_map_single(rx_ring->dev,
1179 						 skb->data,
1180 						 rx_ring->rx_buf_len,
1181 						 DMA_FROM_DEVICE);
1182 			if (dma_mapping_error(rx_ring->dev, bi->dma)) {
1183 				rx_ring->rx_stats.alloc_buff_failed++;
1184 				bi->dma = 0;
1185 				goto no_buffers;
1186 			}
1187 		}
1188 
1189 		if (ring_is_ps_enabled(rx_ring)) {
1190 			if (!bi->page) {
1191 				bi->page = alloc_page(GFP_ATOMIC);
1192 				if (!bi->page) {
1193 					rx_ring->rx_stats.alloc_page_failed++;
1194 					goto no_buffers;
1195 				}
1196 			}
1197 
1198 			if (!bi->page_dma) {
1199 				/* use a half page if we're re-using */
1200 				bi->page_offset ^= PAGE_SIZE / 2;
1201 				bi->page_dma = dma_map_page(rx_ring->dev,
1202 							    bi->page,
1203 							    bi->page_offset,
1204 							    PAGE_SIZE / 2,
1205 							    DMA_FROM_DEVICE);
1206 				if (dma_mapping_error(rx_ring->dev,
1207 						      bi->page_dma)) {
1208 					rx_ring->rx_stats.alloc_page_failed++;
1209 					bi->page_dma = 0;
1210 					goto no_buffers;
1211 				}
1212 			}
1213 
1214 			/* Refresh the desc even if buffer_addrs didn't change
1215 			 * because each write-back erases this info.
1216 			 */
1217 			rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
1218 			rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
1219 		} else {
1220 			rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
1221 			rx_desc->read.hdr_addr = 0;
1222 		}
1223 		i++;
1224 		if (i == rx_ring->count)
1225 			i = 0;
1226 	}
1227 
1228 no_buffers:
1229 	if (rx_ring->next_to_use != i)
1230 		i40e_release_rx_desc(rx_ring, i);
1231 }
1232 
1233 /**
1234  * i40e_receive_skb - Send a completed packet up the stack
1235  * @rx_ring:  rx ring in play
1236  * @skb: packet to send up
1237  * @vlan_tag: vlan tag for packet
1238  **/
1239 static void i40e_receive_skb(struct i40e_ring *rx_ring,
1240 			     struct sk_buff *skb, u16 vlan_tag)
1241 {
1242 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1243 	struct i40e_vsi *vsi = rx_ring->vsi;
1244 	u64 flags = vsi->back->flags;
1245 
1246 	if (vlan_tag & VLAN_VID_MASK)
1247 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1248 
1249 	if (flags & I40E_FLAG_IN_NETPOLL)
1250 		netif_rx(skb);
1251 	else
1252 		napi_gro_receive(&q_vector->napi, skb);
1253 }
1254 
1255 /**
1256  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1257  * @vsi: the VSI we care about
1258  * @skb: skb currently being received and modified
1259  * @rx_status: status value of last descriptor in packet
1260  * @rx_error: error value of last descriptor in packet
1261  * @rx_ptype: ptype value of last descriptor in packet
1262  **/
1263 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1264 				    struct sk_buff *skb,
1265 				    u32 rx_status,
1266 				    u32 rx_error,
1267 				    u16 rx_ptype)
1268 {
1269 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(rx_ptype);
1270 	bool ipv4 = false, ipv6 = false;
1271 	bool ipv4_tunnel, ipv6_tunnel;
1272 	__wsum rx_udp_csum;
1273 	struct iphdr *iph;
1274 	__sum16 csum;
1275 
1276 	ipv4_tunnel = (rx_ptype > I40E_RX_PTYPE_GRENAT4_MAC_PAY3) &&
1277 		      (rx_ptype < I40E_RX_PTYPE_GRENAT4_MACVLAN_IPV6_ICMP_PAY4);
1278 	ipv6_tunnel = (rx_ptype > I40E_RX_PTYPE_GRENAT6_MAC_PAY3) &&
1279 		      (rx_ptype < I40E_RX_PTYPE_GRENAT6_MACVLAN_IPV6_ICMP_PAY4);
1280 
1281 	skb->ip_summed = CHECKSUM_NONE;
1282 
1283 	/* Rx csum enabled and ip headers found? */
1284 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1285 		return;
1286 
1287 	/* did the hardware decode the packet and checksum? */
1288 	if (!(rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1289 		return;
1290 
1291 	/* both known and outer_ip must be set for the below code to work */
1292 	if (!(decoded.known && decoded.outer_ip))
1293 		return;
1294 
1295 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1296 	    decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4)
1297 		ipv4 = true;
1298 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1299 		 decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6)
1300 		ipv6 = true;
1301 
1302 	if (ipv4 &&
1303 	    (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) |
1304 			 (1 << I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1305 		goto checksum_fail;
1306 
1307 	/* likely incorrect csum if alternate IP extension headers found */
1308 	if (ipv6 &&
1309 	    rx_status & (1 << I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1310 		/* don't increment checksum err here, non-fatal err */
1311 		return;
1312 
1313 	/* there was some L4 error, count error and punt packet to the stack */
1314 	if (rx_error & (1 << I40E_RX_DESC_ERROR_L4E_SHIFT))
1315 		goto checksum_fail;
1316 
1317 	/* handle packets that were not able to be checksummed due
1318 	 * to arrival speed, in this case the stack can compute
1319 	 * the csum.
1320 	 */
1321 	if (rx_error & (1 << I40E_RX_DESC_ERROR_PPRS_SHIFT))
1322 		return;
1323 
1324 	/* If VXLAN traffic has an outer UDPv4 checksum we need to check
1325 	 * it in the driver, hardware does not do it for us.
1326 	 * Since L3L4P bit was set we assume a valid IHL value (>=5)
1327 	 * so the total length of IPv4 header is IHL*4 bytes
1328 	 * The UDP_0 bit *may* bet set if the *inner* header is UDP
1329 	 */
1330 	if (ipv4_tunnel) {
1331 		skb->transport_header = skb->mac_header +
1332 					sizeof(struct ethhdr) +
1333 					(ip_hdr(skb)->ihl * 4);
1334 
1335 		/* Add 4 bytes for VLAN tagged packets */
1336 		skb->transport_header += (skb->protocol == htons(ETH_P_8021Q) ||
1337 					  skb->protocol == htons(ETH_P_8021AD))
1338 					  ? VLAN_HLEN : 0;
1339 
1340 		if ((ip_hdr(skb)->protocol == IPPROTO_UDP) &&
1341 		    (udp_hdr(skb)->check != 0)) {
1342 			rx_udp_csum = udp_csum(skb);
1343 			iph = ip_hdr(skb);
1344 			csum = csum_tcpudp_magic(
1345 					iph->saddr, iph->daddr,
1346 					(skb->len - skb_transport_offset(skb)),
1347 					IPPROTO_UDP, rx_udp_csum);
1348 
1349 			if (udp_hdr(skb)->check != csum)
1350 				goto checksum_fail;
1351 
1352 		} /* else its GRE and so no outer UDP header */
1353 	}
1354 
1355 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1356 	skb->csum_level = ipv4_tunnel || ipv6_tunnel;
1357 
1358 	return;
1359 
1360 checksum_fail:
1361 	vsi->back->hw_csum_rx_error++;
1362 }
1363 
1364 /**
1365  * i40e_rx_hash - returns the hash value from the Rx descriptor
1366  * @ring: descriptor ring
1367  * @rx_desc: specific descriptor
1368  **/
1369 static inline u32 i40e_rx_hash(struct i40e_ring *ring,
1370 			       union i40e_rx_desc *rx_desc)
1371 {
1372 	const __le64 rss_mask =
1373 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1374 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1375 
1376 	if ((ring->netdev->features & NETIF_F_RXHASH) &&
1377 	    (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
1378 		return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1379 	else
1380 		return 0;
1381 }
1382 
1383 /**
1384  * i40e_ptype_to_hash - get a hash type
1385  * @ptype: the ptype value from the descriptor
1386  *
1387  * Returns a hash type to be used by skb_set_hash
1388  **/
1389 static inline enum pkt_hash_types i40e_ptype_to_hash(u8 ptype)
1390 {
1391 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1392 
1393 	if (!decoded.known)
1394 		return PKT_HASH_TYPE_NONE;
1395 
1396 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1397 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1398 		return PKT_HASH_TYPE_L4;
1399 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1400 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1401 		return PKT_HASH_TYPE_L3;
1402 	else
1403 		return PKT_HASH_TYPE_L2;
1404 }
1405 
1406 /**
1407  * i40e_clean_rx_irq - Reclaim resources after receive completes
1408  * @rx_ring:  rx ring to clean
1409  * @budget:   how many cleans we're allowed
1410  *
1411  * Returns true if there's any budget left (e.g. the clean is finished)
1412  **/
1413 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
1414 {
1415 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1416 	u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
1417 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1418 	const int current_node = numa_node_id();
1419 	struct i40e_vsi *vsi = rx_ring->vsi;
1420 	u16 i = rx_ring->next_to_clean;
1421 	union i40e_rx_desc *rx_desc;
1422 	u32 rx_error, rx_status;
1423 	u8 rx_ptype;
1424 	u64 qword;
1425 
1426 	if (budget <= 0)
1427 		return 0;
1428 
1429 	rx_desc = I40E_RX_DESC(rx_ring, i);
1430 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1431 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1432 		    I40E_RXD_QW1_STATUS_SHIFT;
1433 
1434 	while (rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)) {
1435 		union i40e_rx_desc *next_rxd;
1436 		struct i40e_rx_buffer *rx_bi;
1437 		struct sk_buff *skb;
1438 		u16 vlan_tag;
1439 		if (i40e_rx_is_programming_status(qword)) {
1440 			i40e_clean_programming_status(rx_ring, rx_desc);
1441 			I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
1442 			goto next_desc;
1443 		}
1444 		rx_bi = &rx_ring->rx_bi[i];
1445 		skb = rx_bi->skb;
1446 		prefetch(skb->data);
1447 
1448 		rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
1449 				I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
1450 		rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK) >>
1451 				I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
1452 		rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK) >>
1453 			 I40E_RXD_QW1_LENGTH_SPH_SHIFT;
1454 
1455 		rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1456 			   I40E_RXD_QW1_ERROR_SHIFT;
1457 		rx_hbo = rx_error & (1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1458 		rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1459 
1460 		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1461 			   I40E_RXD_QW1_PTYPE_SHIFT;
1462 		rx_bi->skb = NULL;
1463 
1464 		/* This memory barrier is needed to keep us from reading
1465 		 * any other fields out of the rx_desc until we know the
1466 		 * STATUS_DD bit is set
1467 		 */
1468 		rmb();
1469 
1470 		/* Get the header and possibly the whole packet
1471 		 * If this is an skb from previous receive dma will be 0
1472 		 */
1473 		if (rx_bi->dma) {
1474 			u16 len;
1475 
1476 			if (rx_hbo)
1477 				len = I40E_RX_HDR_SIZE;
1478 			else if (rx_sph)
1479 				len = rx_header_len;
1480 			else if (rx_packet_len)
1481 				len = rx_packet_len;   /* 1buf/no split found */
1482 			else
1483 				len = rx_header_len;   /* split always mode */
1484 
1485 			skb_put(skb, len);
1486 			dma_unmap_single(rx_ring->dev,
1487 					 rx_bi->dma,
1488 					 rx_ring->rx_buf_len,
1489 					 DMA_FROM_DEVICE);
1490 			rx_bi->dma = 0;
1491 		}
1492 
1493 		/* Get the rest of the data if this was a header split */
1494 		if (ring_is_ps_enabled(rx_ring) && rx_packet_len) {
1495 
1496 			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
1497 					   rx_bi->page,
1498 					   rx_bi->page_offset,
1499 					   rx_packet_len);
1500 
1501 			skb->len += rx_packet_len;
1502 			skb->data_len += rx_packet_len;
1503 			skb->truesize += rx_packet_len;
1504 
1505 			if ((page_count(rx_bi->page) == 1) &&
1506 			    (page_to_nid(rx_bi->page) == current_node))
1507 				get_page(rx_bi->page);
1508 			else
1509 				rx_bi->page = NULL;
1510 
1511 			dma_unmap_page(rx_ring->dev,
1512 				       rx_bi->page_dma,
1513 				       PAGE_SIZE / 2,
1514 				       DMA_FROM_DEVICE);
1515 			rx_bi->page_dma = 0;
1516 		}
1517 		I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
1518 
1519 		if (unlikely(
1520 		    !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1521 			struct i40e_rx_buffer *next_buffer;
1522 
1523 			next_buffer = &rx_ring->rx_bi[i];
1524 
1525 			if (ring_is_ps_enabled(rx_ring)) {
1526 				rx_bi->skb = next_buffer->skb;
1527 				rx_bi->dma = next_buffer->dma;
1528 				next_buffer->skb = skb;
1529 				next_buffer->dma = 0;
1530 			}
1531 			rx_ring->rx_stats.non_eop_descs++;
1532 			goto next_desc;
1533 		}
1534 
1535 		/* ERR_MASK will only have valid bits if EOP set */
1536 		if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1537 			dev_kfree_skb_any(skb);
1538 			/* TODO: shouldn't we increment a counter indicating the
1539 			 * drop?
1540 			 */
1541 			goto next_desc;
1542 		}
1543 
1544 		skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1545 			     i40e_ptype_to_hash(rx_ptype));
1546 		if (unlikely(rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK)) {
1547 			i40e_ptp_rx_hwtstamp(vsi->back, skb, (rx_status &
1548 					   I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1549 					   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT);
1550 			rx_ring->last_rx_timestamp = jiffies;
1551 		}
1552 
1553 		/* probably a little skewed due to removing CRC */
1554 		total_rx_bytes += skb->len;
1555 		total_rx_packets++;
1556 
1557 		skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1558 
1559 		i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1560 
1561 		vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1562 			 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1563 			 : 0;
1564 #ifdef I40E_FCOE
1565 		if (!i40e_fcoe_handle_offload(rx_ring, rx_desc, skb)) {
1566 			dev_kfree_skb_any(skb);
1567 			goto next_desc;
1568 		}
1569 #endif
1570 		i40e_receive_skb(rx_ring, skb, vlan_tag);
1571 
1572 		rx_ring->netdev->last_rx = jiffies;
1573 		budget--;
1574 next_desc:
1575 		rx_desc->wb.qword1.status_error_len = 0;
1576 		if (!budget)
1577 			break;
1578 
1579 		cleaned_count++;
1580 		/* return some buffers to hardware, one at a time is too slow */
1581 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1582 			i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1583 			cleaned_count = 0;
1584 		}
1585 
1586 		/* use prefetched values */
1587 		rx_desc = next_rxd;
1588 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1589 		rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1590 			    I40E_RXD_QW1_STATUS_SHIFT;
1591 	}
1592 
1593 	rx_ring->next_to_clean = i;
1594 	u64_stats_update_begin(&rx_ring->syncp);
1595 	rx_ring->stats.packets += total_rx_packets;
1596 	rx_ring->stats.bytes += total_rx_bytes;
1597 	u64_stats_update_end(&rx_ring->syncp);
1598 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
1599 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1600 
1601 	if (cleaned_count)
1602 		i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1603 
1604 	return budget > 0;
1605 }
1606 
1607 /**
1608  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
1609  * @napi: napi struct with our devices info in it
1610  * @budget: amount of work driver is allowed to do this pass, in packets
1611  *
1612  * This function will clean all queues associated with a q_vector.
1613  *
1614  * Returns the amount of work done
1615  **/
1616 int i40e_napi_poll(struct napi_struct *napi, int budget)
1617 {
1618 	struct i40e_q_vector *q_vector =
1619 			       container_of(napi, struct i40e_q_vector, napi);
1620 	struct i40e_vsi *vsi = q_vector->vsi;
1621 	struct i40e_ring *ring;
1622 	bool clean_complete = true;
1623 	bool arm_wb = false;
1624 	int budget_per_ring;
1625 
1626 	if (test_bit(__I40E_DOWN, &vsi->state)) {
1627 		napi_complete(napi);
1628 		return 0;
1629 	}
1630 
1631 	/* Since the actual Tx work is minimal, we can give the Tx a larger
1632 	 * budget and be more aggressive about cleaning up the Tx descriptors.
1633 	 */
1634 	i40e_for_each_ring(ring, q_vector->tx) {
1635 		clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
1636 		arm_wb |= ring->arm_wb;
1637 	}
1638 
1639 	/* We attempt to distribute budget to each Rx queue fairly, but don't
1640 	 * allow the budget to go below 1 because that would exit polling early.
1641 	 */
1642 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
1643 
1644 	i40e_for_each_ring(ring, q_vector->rx)
1645 		clean_complete &= i40e_clean_rx_irq(ring, budget_per_ring);
1646 
1647 	/* If work not completed, return budget and polling will return */
1648 	if (!clean_complete) {
1649 		if (arm_wb)
1650 			i40e_force_wb(vsi, q_vector);
1651 		return budget;
1652 	}
1653 
1654 	/* Work is done so exit the polling mode and re-enable the interrupt */
1655 	napi_complete(napi);
1656 	if (ITR_IS_DYNAMIC(vsi->rx_itr_setting) ||
1657 	    ITR_IS_DYNAMIC(vsi->tx_itr_setting))
1658 		i40e_update_dynamic_itr(q_vector);
1659 
1660 	if (!test_bit(__I40E_DOWN, &vsi->state)) {
1661 		if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
1662 			i40e_irq_dynamic_enable(vsi,
1663 					q_vector->v_idx + vsi->base_vector);
1664 		} else {
1665 			struct i40e_hw *hw = &vsi->back->hw;
1666 			/* We re-enable the queue 0 cause, but
1667 			 * don't worry about dynamic_enable
1668 			 * because we left it on for the other
1669 			 * possible interrupts during napi
1670 			 */
1671 			u32 qval = rd32(hw, I40E_QINT_RQCTL(0));
1672 			qval |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
1673 			wr32(hw, I40E_QINT_RQCTL(0), qval);
1674 
1675 			qval = rd32(hw, I40E_QINT_TQCTL(0));
1676 			qval |= I40E_QINT_TQCTL_CAUSE_ENA_MASK;
1677 			wr32(hw, I40E_QINT_TQCTL(0), qval);
1678 
1679 			i40e_irq_dynamic_enable_icr0(vsi->back);
1680 		}
1681 	}
1682 
1683 	return 0;
1684 }
1685 
1686 /**
1687  * i40e_atr - Add a Flow Director ATR filter
1688  * @tx_ring:  ring to add programming descriptor to
1689  * @skb:      send buffer
1690  * @flags:    send flags
1691  * @protocol: wire protocol
1692  **/
1693 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
1694 		     u32 flags, __be16 protocol)
1695 {
1696 	struct i40e_filter_program_desc *fdir_desc;
1697 	struct i40e_pf *pf = tx_ring->vsi->back;
1698 	union {
1699 		unsigned char *network;
1700 		struct iphdr *ipv4;
1701 		struct ipv6hdr *ipv6;
1702 	} hdr;
1703 	struct tcphdr *th;
1704 	unsigned int hlen;
1705 	u32 flex_ptype, dtype_cmd;
1706 	u16 i;
1707 
1708 	/* make sure ATR is enabled */
1709 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
1710 		return;
1711 
1712 	/* if sampling is disabled do nothing */
1713 	if (!tx_ring->atr_sample_rate)
1714 		return;
1715 
1716 	/* snag network header to get L4 type and address */
1717 	hdr.network = skb_network_header(skb);
1718 
1719 	/* Currently only IPv4/IPv6 with TCP is supported */
1720 	if (protocol == htons(ETH_P_IP)) {
1721 		if (hdr.ipv4->protocol != IPPROTO_TCP)
1722 			return;
1723 
1724 		/* access ihl as a u8 to avoid unaligned access on ia64 */
1725 		hlen = (hdr.network[0] & 0x0F) << 2;
1726 	} else if (protocol == htons(ETH_P_IPV6)) {
1727 		if (hdr.ipv6->nexthdr != IPPROTO_TCP)
1728 			return;
1729 
1730 		hlen = sizeof(struct ipv6hdr);
1731 	} else {
1732 		return;
1733 	}
1734 
1735 	th = (struct tcphdr *)(hdr.network + hlen);
1736 
1737 	/* Due to lack of space, no more new filters can be programmed */
1738 	if (th->syn && (pf->auto_disable_flags & I40E_FLAG_FD_ATR_ENABLED))
1739 		return;
1740 
1741 	tx_ring->atr_count++;
1742 
1743 	/* sample on all syn/fin/rst packets or once every atr sample rate */
1744 	if (!th->fin &&
1745 	    !th->syn &&
1746 	    !th->rst &&
1747 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
1748 		return;
1749 
1750 	tx_ring->atr_count = 0;
1751 
1752 	/* grab the next descriptor */
1753 	i = tx_ring->next_to_use;
1754 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
1755 
1756 	i++;
1757 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1758 
1759 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
1760 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
1761 	flex_ptype |= (protocol == htons(ETH_P_IP)) ?
1762 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
1763 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
1764 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
1765 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
1766 
1767 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
1768 
1769 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
1770 
1771 	dtype_cmd |= (th->fin || th->rst) ?
1772 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
1773 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
1774 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
1775 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
1776 
1777 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
1778 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
1779 
1780 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
1781 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
1782 
1783 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
1784 	dtype_cmd |=
1785 		((u32)pf->fd_atr_cnt_idx << I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
1786 		I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
1787 
1788 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
1789 	fdir_desc->rsvd = cpu_to_le32(0);
1790 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
1791 	fdir_desc->fd_id = cpu_to_le32(0);
1792 }
1793 
1794 /**
1795  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
1796  * @skb:     send buffer
1797  * @tx_ring: ring to send buffer on
1798  * @flags:   the tx flags to be set
1799  *
1800  * Checks the skb and set up correspondingly several generic transmit flags
1801  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1802  *
1803  * Returns error code indicate the frame should be dropped upon error and the
1804  * otherwise  returns 0 to indicate the flags has been set properly.
1805  **/
1806 #ifdef I40E_FCOE
1807 int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
1808 			       struct i40e_ring *tx_ring,
1809 			       u32 *flags)
1810 #else
1811 static int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
1812 				      struct i40e_ring *tx_ring,
1813 				      u32 *flags)
1814 #endif
1815 {
1816 	__be16 protocol = skb->protocol;
1817 	u32  tx_flags = 0;
1818 
1819 	/* if we have a HW VLAN tag being added, default to the HW one */
1820 	if (skb_vlan_tag_present(skb)) {
1821 		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
1822 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1823 	/* else if it is a SW VLAN, check the next protocol and store the tag */
1824 	} else if (protocol == htons(ETH_P_8021Q)) {
1825 		struct vlan_hdr *vhdr, _vhdr;
1826 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
1827 		if (!vhdr)
1828 			return -EINVAL;
1829 
1830 		protocol = vhdr->h_vlan_encapsulated_proto;
1831 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
1832 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
1833 	}
1834 
1835 	/* Insert 802.1p priority into VLAN header */
1836 	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
1837 	    (skb->priority != TC_PRIO_CONTROL)) {
1838 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
1839 		tx_flags |= (skb->priority & 0x7) <<
1840 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
1841 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
1842 			struct vlan_ethhdr *vhdr;
1843 			int rc;
1844 
1845 			rc = skb_cow_head(skb, 0);
1846 			if (rc < 0)
1847 				return rc;
1848 			vhdr = (struct vlan_ethhdr *)skb->data;
1849 			vhdr->h_vlan_TCI = htons(tx_flags >>
1850 						 I40E_TX_FLAGS_VLAN_SHIFT);
1851 		} else {
1852 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1853 		}
1854 	}
1855 	*flags = tx_flags;
1856 	return 0;
1857 }
1858 
1859 /**
1860  * i40e_tso - set up the tso context descriptor
1861  * @tx_ring:  ptr to the ring to send
1862  * @skb:      ptr to the skb we're sending
1863  * @tx_flags: the collected send information
1864  * @protocol: the send protocol
1865  * @hdr_len:  ptr to the size of the packet header
1866  * @cd_tunneling: ptr to context descriptor bits
1867  *
1868  * Returns 0 if no TSO can happen, 1 if tso is going, or error
1869  **/
1870 static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
1871 		    u32 tx_flags, __be16 protocol, u8 *hdr_len,
1872 		    u64 *cd_type_cmd_tso_mss, u32 *cd_tunneling)
1873 {
1874 	u32 cd_cmd, cd_tso_len, cd_mss;
1875 	struct ipv6hdr *ipv6h;
1876 	struct tcphdr *tcph;
1877 	struct iphdr *iph;
1878 	u32 l4len;
1879 	int err;
1880 
1881 	if (!skb_is_gso(skb))
1882 		return 0;
1883 
1884 	err = skb_cow_head(skb, 0);
1885 	if (err < 0)
1886 		return err;
1887 
1888 	iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
1889 	ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
1890 
1891 	if (iph->version == 4) {
1892 		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1893 		iph->tot_len = 0;
1894 		iph->check = 0;
1895 		tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
1896 						 0, IPPROTO_TCP, 0);
1897 	} else if (ipv6h->version == 6) {
1898 		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1899 		ipv6h->payload_len = 0;
1900 		tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
1901 					       0, IPPROTO_TCP, 0);
1902 	}
1903 
1904 	l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
1905 	*hdr_len = (skb->encapsulation
1906 		    ? (skb_inner_transport_header(skb) - skb->data)
1907 		    : skb_transport_offset(skb)) + l4len;
1908 
1909 	/* find the field values */
1910 	cd_cmd = I40E_TX_CTX_DESC_TSO;
1911 	cd_tso_len = skb->len - *hdr_len;
1912 	cd_mss = skb_shinfo(skb)->gso_size;
1913 	*cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
1914 				((u64)cd_tso_len <<
1915 				 I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
1916 				((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
1917 	return 1;
1918 }
1919 
1920 /**
1921  * i40e_tsyn - set up the tsyn context descriptor
1922  * @tx_ring:  ptr to the ring to send
1923  * @skb:      ptr to the skb we're sending
1924  * @tx_flags: the collected send information
1925  *
1926  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
1927  **/
1928 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
1929 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
1930 {
1931 	struct i40e_pf *pf;
1932 
1933 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
1934 		return 0;
1935 
1936 	/* Tx timestamps cannot be sampled when doing TSO */
1937 	if (tx_flags & I40E_TX_FLAGS_TSO)
1938 		return 0;
1939 
1940 	/* only timestamp the outbound packet if the user has requested it and
1941 	 * we are not already transmitting a packet to be timestamped
1942 	 */
1943 	pf = i40e_netdev_to_pf(tx_ring->netdev);
1944 	if (!(pf->flags & I40E_FLAG_PTP))
1945 		return 0;
1946 
1947 	if (pf->ptp_tx &&
1948 	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, &pf->state)) {
1949 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
1950 		pf->ptp_tx_skb = skb_get(skb);
1951 	} else {
1952 		return 0;
1953 	}
1954 
1955 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
1956 				I40E_TXD_CTX_QW1_CMD_SHIFT;
1957 
1958 	return 1;
1959 }
1960 
1961 /**
1962  * i40e_tx_enable_csum - Enable Tx checksum offloads
1963  * @skb: send buffer
1964  * @tx_flags: Tx flags currently set
1965  * @td_cmd: Tx descriptor command bits to set
1966  * @td_offset: Tx descriptor header offsets to set
1967  * @cd_tunneling: ptr to context desc bits
1968  **/
1969 static void i40e_tx_enable_csum(struct sk_buff *skb, u32 tx_flags,
1970 				u32 *td_cmd, u32 *td_offset,
1971 				struct i40e_ring *tx_ring,
1972 				u32 *cd_tunneling)
1973 {
1974 	struct ipv6hdr *this_ipv6_hdr;
1975 	unsigned int this_tcp_hdrlen;
1976 	struct iphdr *this_ip_hdr;
1977 	u32 network_hdr_len;
1978 	u8 l4_hdr = 0;
1979 
1980 	if (skb->encapsulation) {
1981 		network_hdr_len = skb_inner_network_header_len(skb);
1982 		this_ip_hdr = inner_ip_hdr(skb);
1983 		this_ipv6_hdr = inner_ipv6_hdr(skb);
1984 		this_tcp_hdrlen = inner_tcp_hdrlen(skb);
1985 
1986 		if (tx_flags & I40E_TX_FLAGS_IPV4) {
1987 
1988 			if (tx_flags & I40E_TX_FLAGS_TSO) {
1989 				*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
1990 				ip_hdr(skb)->check = 0;
1991 			} else {
1992 				*cd_tunneling |=
1993 					 I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1994 			}
1995 		} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
1996 			*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
1997 			if (tx_flags & I40E_TX_FLAGS_TSO)
1998 				ip_hdr(skb)->check = 0;
1999 		}
2000 
2001 		/* Now set the ctx descriptor fields */
2002 		*cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
2003 					I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
2004 				   I40E_TXD_CTX_UDP_TUNNELING            |
2005 				   ((skb_inner_network_offset(skb) -
2006 					skb_transport_offset(skb)) >> 1) <<
2007 				   I40E_TXD_CTX_QW0_NATLEN_SHIFT;
2008 		if (this_ip_hdr->version == 6) {
2009 			tx_flags &= ~I40E_TX_FLAGS_IPV4;
2010 			tx_flags |= I40E_TX_FLAGS_IPV6;
2011 		}
2012 	} else {
2013 		network_hdr_len = skb_network_header_len(skb);
2014 		this_ip_hdr = ip_hdr(skb);
2015 		this_ipv6_hdr = ipv6_hdr(skb);
2016 		this_tcp_hdrlen = tcp_hdrlen(skb);
2017 	}
2018 
2019 	/* Enable IP checksum offloads */
2020 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2021 		l4_hdr = this_ip_hdr->protocol;
2022 		/* the stack computes the IP header already, the only time we
2023 		 * need the hardware to recompute it is in the case of TSO.
2024 		 */
2025 		if (tx_flags & I40E_TX_FLAGS_TSO) {
2026 			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
2027 			this_ip_hdr->check = 0;
2028 		} else {
2029 			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
2030 		}
2031 		/* Now set the td_offset for IP header length */
2032 		*td_offset = (network_hdr_len >> 2) <<
2033 			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2034 	} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
2035 		l4_hdr = this_ipv6_hdr->nexthdr;
2036 		*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
2037 		/* Now set the td_offset for IP header length */
2038 		*td_offset = (network_hdr_len >> 2) <<
2039 			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2040 	}
2041 	/* words in MACLEN + dwords in IPLEN + dwords in L4Len */
2042 	*td_offset |= (skb_network_offset(skb) >> 1) <<
2043 		       I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
2044 
2045 	/* Enable L4 checksum offloads */
2046 	switch (l4_hdr) {
2047 	case IPPROTO_TCP:
2048 		/* enable checksum offloads */
2049 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
2050 		*td_offset |= (this_tcp_hdrlen >> 2) <<
2051 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2052 		break;
2053 	case IPPROTO_SCTP:
2054 		/* enable SCTP checksum offload */
2055 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
2056 		*td_offset |= (sizeof(struct sctphdr) >> 2) <<
2057 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2058 		break;
2059 	case IPPROTO_UDP:
2060 		/* enable UDP checksum offload */
2061 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
2062 		*td_offset |= (sizeof(struct udphdr) >> 2) <<
2063 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2064 		break;
2065 	default:
2066 		break;
2067 	}
2068 }
2069 
2070 /**
2071  * i40e_create_tx_ctx Build the Tx context descriptor
2072  * @tx_ring:  ring to create the descriptor on
2073  * @cd_type_cmd_tso_mss: Quad Word 1
2074  * @cd_tunneling: Quad Word 0 - bits 0-31
2075  * @cd_l2tag2: Quad Word 0 - bits 32-63
2076  **/
2077 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
2078 			       const u64 cd_type_cmd_tso_mss,
2079 			       const u32 cd_tunneling, const u32 cd_l2tag2)
2080 {
2081 	struct i40e_tx_context_desc *context_desc;
2082 	int i = tx_ring->next_to_use;
2083 
2084 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
2085 	    !cd_tunneling && !cd_l2tag2)
2086 		return;
2087 
2088 	/* grab the next descriptor */
2089 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
2090 
2091 	i++;
2092 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2093 
2094 	/* cpu_to_le32 and assign to struct fields */
2095 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2096 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2097 	context_desc->rsvd = cpu_to_le16(0);
2098 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2099 }
2100 
2101 /**
2102  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2103  * @tx_ring: the ring to be checked
2104  * @size:    the size buffer we want to assure is available
2105  *
2106  * Returns -EBUSY if a stop is needed, else 0
2107  **/
2108 static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2109 {
2110 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2111 	/* Memory barrier before checking head and tail */
2112 	smp_mb();
2113 
2114 	/* Check again in a case another CPU has just made room available. */
2115 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2116 		return -EBUSY;
2117 
2118 	/* A reprieve! - use start_queue because it doesn't call schedule */
2119 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
2120 	++tx_ring->tx_stats.restart_queue;
2121 	return 0;
2122 }
2123 
2124 /**
2125  * i40e_maybe_stop_tx - 1st level check for tx stop conditions
2126  * @tx_ring: the ring to be checked
2127  * @size:    the size buffer we want to assure is available
2128  *
2129  * Returns 0 if stop is not needed
2130  **/
2131 #ifdef I40E_FCOE
2132 int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2133 #else
2134 static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2135 #endif
2136 {
2137 	if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
2138 		return 0;
2139 	return __i40e_maybe_stop_tx(tx_ring, size);
2140 }
2141 
2142 /**
2143  * i40e_tx_map - Build the Tx descriptor
2144  * @tx_ring:  ring to send buffer on
2145  * @skb:      send buffer
2146  * @first:    first buffer info buffer to use
2147  * @tx_flags: collected send information
2148  * @hdr_len:  size of the packet header
2149  * @td_cmd:   the command field in the descriptor
2150  * @td_offset: offset for checksum or crc
2151  **/
2152 #ifdef I40E_FCOE
2153 void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2154 		 struct i40e_tx_buffer *first, u32 tx_flags,
2155 		 const u8 hdr_len, u32 td_cmd, u32 td_offset)
2156 #else
2157 static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2158 			struct i40e_tx_buffer *first, u32 tx_flags,
2159 			const u8 hdr_len, u32 td_cmd, u32 td_offset)
2160 #endif
2161 {
2162 	unsigned int data_len = skb->data_len;
2163 	unsigned int size = skb_headlen(skb);
2164 	struct skb_frag_struct *frag;
2165 	struct i40e_tx_buffer *tx_bi;
2166 	struct i40e_tx_desc *tx_desc;
2167 	u16 i = tx_ring->next_to_use;
2168 	u32 td_tag = 0;
2169 	dma_addr_t dma;
2170 	u16 gso_segs;
2171 
2172 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
2173 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
2174 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
2175 			 I40E_TX_FLAGS_VLAN_SHIFT;
2176 	}
2177 
2178 	if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
2179 		gso_segs = skb_shinfo(skb)->gso_segs;
2180 	else
2181 		gso_segs = 1;
2182 
2183 	/* multiply data chunks by size of headers */
2184 	first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
2185 	first->gso_segs = gso_segs;
2186 	first->skb = skb;
2187 	first->tx_flags = tx_flags;
2188 
2189 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
2190 
2191 	tx_desc = I40E_TX_DESC(tx_ring, i);
2192 	tx_bi = first;
2193 
2194 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
2195 		if (dma_mapping_error(tx_ring->dev, dma))
2196 			goto dma_error;
2197 
2198 		/* record length, and DMA address */
2199 		dma_unmap_len_set(tx_bi, len, size);
2200 		dma_unmap_addr_set(tx_bi, dma, dma);
2201 
2202 		tx_desc->buffer_addr = cpu_to_le64(dma);
2203 
2204 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
2205 			tx_desc->cmd_type_offset_bsz =
2206 				build_ctob(td_cmd, td_offset,
2207 					   I40E_MAX_DATA_PER_TXD, td_tag);
2208 
2209 			tx_desc++;
2210 			i++;
2211 			if (i == tx_ring->count) {
2212 				tx_desc = I40E_TX_DESC(tx_ring, 0);
2213 				i = 0;
2214 			}
2215 
2216 			dma += I40E_MAX_DATA_PER_TXD;
2217 			size -= I40E_MAX_DATA_PER_TXD;
2218 
2219 			tx_desc->buffer_addr = cpu_to_le64(dma);
2220 		}
2221 
2222 		if (likely(!data_len))
2223 			break;
2224 
2225 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
2226 							  size, td_tag);
2227 
2228 		tx_desc++;
2229 		i++;
2230 		if (i == tx_ring->count) {
2231 			tx_desc = I40E_TX_DESC(tx_ring, 0);
2232 			i = 0;
2233 		}
2234 
2235 		size = skb_frag_size(frag);
2236 		data_len -= size;
2237 
2238 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
2239 				       DMA_TO_DEVICE);
2240 
2241 		tx_bi = &tx_ring->tx_bi[i];
2242 	}
2243 
2244 	/* Place RS bit on last descriptor of any packet that spans across the
2245 	 * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
2246 	 */
2247 	if (((i & WB_STRIDE) != WB_STRIDE) &&
2248 	    (first <= &tx_ring->tx_bi[i]) &&
2249 	    (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
2250 		tx_desc->cmd_type_offset_bsz =
2251 			build_ctob(td_cmd, td_offset, size, td_tag) |
2252 			cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
2253 					 I40E_TXD_QW1_CMD_SHIFT);
2254 	} else {
2255 		tx_desc->cmd_type_offset_bsz =
2256 			build_ctob(td_cmd, td_offset, size, td_tag) |
2257 			cpu_to_le64((u64)I40E_TXD_CMD <<
2258 					 I40E_TXD_QW1_CMD_SHIFT);
2259 	}
2260 
2261 	netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
2262 						 tx_ring->queue_index),
2263 			     first->bytecount);
2264 
2265 	/* set the timestamp */
2266 	first->time_stamp = jiffies;
2267 
2268 	/* Force memory writes to complete before letting h/w
2269 	 * know there are new descriptors to fetch.  (Only
2270 	 * applicable for weak-ordered memory model archs,
2271 	 * such as IA-64).
2272 	 */
2273 	wmb();
2274 
2275 	/* set next_to_watch value indicating a packet is present */
2276 	first->next_to_watch = tx_desc;
2277 
2278 	i++;
2279 	if (i == tx_ring->count)
2280 		i = 0;
2281 
2282 	tx_ring->next_to_use = i;
2283 
2284 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
2285 	/* notify HW of packet */
2286 	if (!skb->xmit_more ||
2287 	    netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
2288 						   tx_ring->queue_index)))
2289 		writel(i, tx_ring->tail);
2290 
2291 	return;
2292 
2293 dma_error:
2294 	dev_info(tx_ring->dev, "TX DMA map failed\n");
2295 
2296 	/* clear dma mappings for failed tx_bi map */
2297 	for (;;) {
2298 		tx_bi = &tx_ring->tx_bi[i];
2299 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
2300 		if (tx_bi == first)
2301 			break;
2302 		if (i == 0)
2303 			i = tx_ring->count;
2304 		i--;
2305 	}
2306 
2307 	tx_ring->next_to_use = i;
2308 }
2309 
2310 /**
2311  * i40e_xmit_descriptor_count - calculate number of tx descriptors needed
2312  * @skb:     send buffer
2313  * @tx_ring: ring to send buffer on
2314  *
2315  * Returns number of data descriptors needed for this skb. Returns 0 to indicate
2316  * there is not enough descriptors available in this ring since we need at least
2317  * one descriptor.
2318  **/
2319 #ifdef I40E_FCOE
2320 int i40e_xmit_descriptor_count(struct sk_buff *skb,
2321 			       struct i40e_ring *tx_ring)
2322 #else
2323 static int i40e_xmit_descriptor_count(struct sk_buff *skb,
2324 				      struct i40e_ring *tx_ring)
2325 #endif
2326 {
2327 	unsigned int f;
2328 	int count = 0;
2329 
2330 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
2331 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
2332 	 *       + 4 desc gap to avoid the cache line where head is,
2333 	 *       + 1 desc for context descriptor,
2334 	 * otherwise try next time
2335 	 */
2336 	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
2337 		count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
2338 
2339 	count += TXD_USE_COUNT(skb_headlen(skb));
2340 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
2341 		tx_ring->tx_stats.tx_busy++;
2342 		return 0;
2343 	}
2344 	return count;
2345 }
2346 
2347 /**
2348  * i40e_xmit_frame_ring - Sends buffer on Tx ring
2349  * @skb:     send buffer
2350  * @tx_ring: ring to send buffer on
2351  *
2352  * Returns NETDEV_TX_OK if sent, else an error code
2353  **/
2354 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
2355 					struct i40e_ring *tx_ring)
2356 {
2357 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
2358 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
2359 	struct i40e_tx_buffer *first;
2360 	u32 td_offset = 0;
2361 	u32 tx_flags = 0;
2362 	__be16 protocol;
2363 	u32 td_cmd = 0;
2364 	u8 hdr_len = 0;
2365 	int tsyn;
2366 	int tso;
2367 	if (0 == i40e_xmit_descriptor_count(skb, tx_ring))
2368 		return NETDEV_TX_BUSY;
2369 
2370 	/* prepare the xmit flags */
2371 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
2372 		goto out_drop;
2373 
2374 	/* obtain protocol of skb */
2375 	protocol = vlan_get_protocol(skb);
2376 
2377 	/* record the location of the first descriptor for this packet */
2378 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
2379 
2380 	/* setup IPv4/IPv6 offloads */
2381 	if (protocol == htons(ETH_P_IP))
2382 		tx_flags |= I40E_TX_FLAGS_IPV4;
2383 	else if (protocol == htons(ETH_P_IPV6))
2384 		tx_flags |= I40E_TX_FLAGS_IPV6;
2385 
2386 	tso = i40e_tso(tx_ring, skb, tx_flags, protocol, &hdr_len,
2387 		       &cd_type_cmd_tso_mss, &cd_tunneling);
2388 
2389 	if (tso < 0)
2390 		goto out_drop;
2391 	else if (tso)
2392 		tx_flags |= I40E_TX_FLAGS_TSO;
2393 
2394 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
2395 
2396 	if (tsyn)
2397 		tx_flags |= I40E_TX_FLAGS_TSYN;
2398 
2399 	skb_tx_timestamp(skb);
2400 
2401 	/* always enable CRC insertion offload */
2402 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
2403 
2404 	/* Always offload the checksum, since it's in the data descriptor */
2405 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
2406 		tx_flags |= I40E_TX_FLAGS_CSUM;
2407 
2408 		i40e_tx_enable_csum(skb, tx_flags, &td_cmd, &td_offset,
2409 				    tx_ring, &cd_tunneling);
2410 	}
2411 
2412 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
2413 			   cd_tunneling, cd_l2tag2);
2414 
2415 	/* Add Flow Director ATR if it's enabled.
2416 	 *
2417 	 * NOTE: this must always be directly before the data descriptor.
2418 	 */
2419 	i40e_atr(tx_ring, skb, tx_flags, protocol);
2420 
2421 	i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
2422 		    td_cmd, td_offset);
2423 
2424 	return NETDEV_TX_OK;
2425 
2426 out_drop:
2427 	dev_kfree_skb_any(skb);
2428 	return NETDEV_TX_OK;
2429 }
2430 
2431 /**
2432  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
2433  * @skb:    send buffer
2434  * @netdev: network interface device structure
2435  *
2436  * Returns NETDEV_TX_OK if sent, else an error code
2437  **/
2438 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
2439 {
2440 	struct i40e_netdev_priv *np = netdev_priv(netdev);
2441 	struct i40e_vsi *vsi = np->vsi;
2442 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
2443 
2444 	/* hardware can't handle really short frames, hardware padding works
2445 	 * beyond this point
2446 	 */
2447 	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
2448 		return NETDEV_TX_OK;
2449 
2450 	return i40e_xmit_frame_ring(skb, tx_ring);
2451 }
2452