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 /**
43  * i40e_program_fdir_filter - Program a Flow Director filter
44  * @fdir_data: Packet data that will be filter parameters
45  * @raw_packet: the pre-allocated packet buffer for FDir
46  * @pf: The pf pointer
47  * @add: True for add/update, False for remove
48  **/
49 int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data, u8 *raw_packet,
50 			     struct i40e_pf *pf, bool add)
51 {
52 	struct i40e_filter_program_desc *fdir_desc;
53 	struct i40e_tx_buffer *tx_buf;
54 	struct i40e_tx_desc *tx_desc;
55 	struct i40e_ring *tx_ring;
56 	unsigned int fpt, dcc;
57 	struct i40e_vsi *vsi;
58 	struct device *dev;
59 	dma_addr_t dma;
60 	u32 td_cmd = 0;
61 	u16 i;
62 
63 	/* find existing FDIR VSI */
64 	vsi = NULL;
65 	for (i = 0; i < pf->num_alloc_vsi; i++)
66 		if (pf->vsi[i] && pf->vsi[i]->type == I40E_VSI_FDIR)
67 			vsi = pf->vsi[i];
68 	if (!vsi)
69 		return -ENOENT;
70 
71 	tx_ring = vsi->tx_rings[0];
72 	dev = tx_ring->dev;
73 
74 	dma = dma_map_single(dev, raw_packet,
75 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
76 	if (dma_mapping_error(dev, dma))
77 		goto dma_fail;
78 
79 	/* grab the next descriptor */
80 	i = tx_ring->next_to_use;
81 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
82 
83 	tx_ring->next_to_use = (i + 1 < tx_ring->count) ? i + 1 : 0;
84 
85 	fpt = (fdir_data->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
86 	      I40E_TXD_FLTR_QW0_QINDEX_MASK;
87 
88 	fpt |= (fdir_data->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT) &
89 	       I40E_TXD_FLTR_QW0_FLEXOFF_MASK;
90 
91 	fpt |= (fdir_data->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) &
92 	       I40E_TXD_FLTR_QW0_PCTYPE_MASK;
93 
94 	/* Use LAN VSI Id if not programmed by user */
95 	if (fdir_data->dest_vsi == 0)
96 		fpt |= (pf->vsi[pf->lan_vsi]->id) <<
97 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
98 	else
99 		fpt |= ((u32)fdir_data->dest_vsi <<
100 			I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT) &
101 		       I40E_TXD_FLTR_QW0_DEST_VSI_MASK;
102 
103 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(fpt);
104 
105 	dcc = I40E_TX_DESC_DTYPE_FILTER_PROG;
106 
107 	if (add)
108 		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
109 		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
110 	else
111 		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
112 		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
113 
114 	dcc |= (fdir_data->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT) &
115 	       I40E_TXD_FLTR_QW1_DEST_MASK;
116 
117 	dcc |= (fdir_data->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT) &
118 	       I40E_TXD_FLTR_QW1_FD_STATUS_MASK;
119 
120 	if (fdir_data->cnt_index != 0) {
121 		dcc |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
122 		dcc |= ((u32)fdir_data->cnt_index <<
123 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
124 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
125 	}
126 
127 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dcc);
128 	fdir_desc->fd_id = cpu_to_le32(fdir_data->fd_id);
129 
130 	/* Now program a dummy descriptor */
131 	i = tx_ring->next_to_use;
132 	tx_desc = I40E_TX_DESC(tx_ring, i);
133 	tx_buf = &tx_ring->tx_bi[i];
134 
135 	tx_ring->next_to_use = (i + 1 < tx_ring->count) ? i + 1 : 0;
136 
137 	/* record length, and DMA address */
138 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
139 	dma_unmap_addr_set(tx_buf, dma, dma);
140 
141 	tx_desc->buffer_addr = cpu_to_le64(dma);
142 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
143 
144 	tx_desc->cmd_type_offset_bsz =
145 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
146 
147 	/* set the timestamp */
148 	tx_buf->time_stamp = jiffies;
149 
150 	/* Force memory writes to complete before letting h/w
151 	 * know there are new descriptors to fetch.  (Only
152 	 * applicable for weak-ordered memory model archs,
153 	 * such as IA-64).
154 	 */
155 	wmb();
156 
157 	/* Mark the data descriptor to be watched */
158 	tx_buf->next_to_watch = tx_desc;
159 
160 	writel(tx_ring->next_to_use, tx_ring->tail);
161 	return 0;
162 
163 dma_fail:
164 	return -1;
165 }
166 
167 #define IP_HEADER_OFFSET 14
168 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
169 /**
170  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
171  * @vsi: pointer to the targeted VSI
172  * @fd_data: the flow director data required for the FDir descriptor
173  * @raw_packet: the pre-allocated packet buffer for FDir
174  * @add: true adds a filter, false removes it
175  *
176  * Returns 0 if the filters were successfully added or removed
177  **/
178 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
179 				   struct i40e_fdir_filter *fd_data,
180 				   u8 *raw_packet, bool add)
181 {
182 	struct i40e_pf *pf = vsi->back;
183 	struct udphdr *udp;
184 	struct iphdr *ip;
185 	bool err = false;
186 	int ret;
187 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
188 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
189 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
190 
191 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
192 
193 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
194 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
195 	      + sizeof(struct iphdr));
196 
197 	ip->daddr = fd_data->dst_ip[0];
198 	udp->dest = fd_data->dst_port;
199 	ip->saddr = fd_data->src_ip[0];
200 	udp->source = fd_data->src_port;
201 
202 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
203 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
204 	if (ret) {
205 		dev_info(&pf->pdev->dev,
206 			 "Filter command send failed for PCTYPE %d (ret = %d)\n",
207 			 fd_data->pctype, ret);
208 		err = true;
209 	} else {
210 		dev_info(&pf->pdev->dev,
211 			 "Filter OK for PCTYPE %d (ret = %d)\n",
212 			 fd_data->pctype, ret);
213 	}
214 
215 	return err ? -EOPNOTSUPP : 0;
216 }
217 
218 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
219 /**
220  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
221  * @vsi: pointer to the targeted VSI
222  * @fd_data: the flow director data required for the FDir descriptor
223  * @raw_packet: the pre-allocated packet buffer for FDir
224  * @add: true adds a filter, false removes it
225  *
226  * Returns 0 if the filters were successfully added or removed
227  **/
228 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
229 				   struct i40e_fdir_filter *fd_data,
230 				   u8 *raw_packet, bool add)
231 {
232 	struct i40e_pf *pf = vsi->back;
233 	struct tcphdr *tcp;
234 	struct iphdr *ip;
235 	bool err = false;
236 	int ret;
237 	/* Dummy packet */
238 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
239 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
240 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
241 		0x0, 0x72, 0, 0, 0, 0};
242 
243 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
244 
245 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
246 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
247 	      + sizeof(struct iphdr));
248 
249 	ip->daddr = fd_data->dst_ip[0];
250 	tcp->dest = fd_data->dst_port;
251 	ip->saddr = fd_data->src_ip[0];
252 	tcp->source = fd_data->src_port;
253 
254 	if (add) {
255 		if (pf->flags & I40E_FLAG_FD_ATR_ENABLED) {
256 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
257 			pf->flags &= ~I40E_FLAG_FD_ATR_ENABLED;
258 		}
259 	}
260 
261 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
262 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
263 
264 	if (ret) {
265 		dev_info(&pf->pdev->dev,
266 			 "Filter command send failed for PCTYPE %d (ret = %d)\n",
267 			 fd_data->pctype, ret);
268 		err = true;
269 	} else {
270 		dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d (ret = %d)\n",
271 			 fd_data->pctype, ret);
272 	}
273 
274 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
275 
276 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
277 	if (ret) {
278 		dev_info(&pf->pdev->dev,
279 			 "Filter command send failed for PCTYPE %d (ret = %d)\n",
280 			 fd_data->pctype, ret);
281 		err = true;
282 	} else {
283 		dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d (ret = %d)\n",
284 			  fd_data->pctype, ret);
285 	}
286 
287 	return err ? -EOPNOTSUPP : 0;
288 }
289 
290 /**
291  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
292  * a specific flow spec
293  * @vsi: pointer to the targeted VSI
294  * @fd_data: the flow director data required for the FDir descriptor
295  * @raw_packet: the pre-allocated packet buffer for FDir
296  * @add: true adds a filter, false removes it
297  *
298  * Always returns -EOPNOTSUPP
299  **/
300 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
301 				    struct i40e_fdir_filter *fd_data,
302 				    u8 *raw_packet, bool add)
303 {
304 	return -EOPNOTSUPP;
305 }
306 
307 #define I40E_IP_DUMMY_PACKET_LEN 34
308 /**
309  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
310  * a specific flow spec
311  * @vsi: pointer to the targeted VSI
312  * @fd_data: the flow director data required for the FDir descriptor
313  * @raw_packet: the pre-allocated packet buffer for FDir
314  * @add: true adds a filter, false removes it
315  *
316  * Returns 0 if the filters were successfully added or removed
317  **/
318 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
319 				  struct i40e_fdir_filter *fd_data,
320 				  u8 *raw_packet, bool add)
321 {
322 	struct i40e_pf *pf = vsi->back;
323 	struct iphdr *ip;
324 	bool err = false;
325 	int ret;
326 	int i;
327 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
328 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
329 		0, 0, 0, 0};
330 
331 	memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
332 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
333 
334 	ip->saddr = fd_data->src_ip[0];
335 	ip->daddr = fd_data->dst_ip[0];
336 	ip->protocol = 0;
337 
338 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
339 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
340 		fd_data->pctype = i;
341 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
342 
343 		if (ret) {
344 			dev_info(&pf->pdev->dev,
345 				 "Filter command send failed for PCTYPE %d (ret = %d)\n",
346 				 fd_data->pctype, ret);
347 			err = true;
348 		} else {
349 			dev_info(&pf->pdev->dev,
350 				 "Filter OK for PCTYPE %d (ret = %d)\n",
351 				 fd_data->pctype, ret);
352 		}
353 	}
354 
355 	return err ? -EOPNOTSUPP : 0;
356 }
357 
358 /**
359  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
360  * @vsi: pointer to the targeted VSI
361  * @cmd: command to get or set RX flow classification rules
362  * @add: true adds a filter, false removes it
363  *
364  **/
365 int i40e_add_del_fdir(struct i40e_vsi *vsi,
366 		      struct i40e_fdir_filter *input, bool add)
367 {
368 	struct i40e_pf *pf = vsi->back;
369 	u8 *raw_packet;
370 	int ret;
371 
372 	/* Populate the Flow Director that we have at the moment
373 	 * and allocate the raw packet buffer for the calling functions
374 	 */
375 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
376 	if (!raw_packet)
377 		return -ENOMEM;
378 
379 	switch (input->flow_type & ~FLOW_EXT) {
380 	case TCP_V4_FLOW:
381 		ret = i40e_add_del_fdir_tcpv4(vsi, input, raw_packet,
382 					      add);
383 		break;
384 	case UDP_V4_FLOW:
385 		ret = i40e_add_del_fdir_udpv4(vsi, input, raw_packet,
386 					      add);
387 		break;
388 	case SCTP_V4_FLOW:
389 		ret = i40e_add_del_fdir_sctpv4(vsi, input, raw_packet,
390 					       add);
391 		break;
392 	case IPV4_FLOW:
393 		ret = i40e_add_del_fdir_ipv4(vsi, input, raw_packet,
394 					     add);
395 		break;
396 	case IP_USER_FLOW:
397 		switch (input->ip4_proto) {
398 		case IPPROTO_TCP:
399 			ret = i40e_add_del_fdir_tcpv4(vsi, input,
400 						      raw_packet, add);
401 			break;
402 		case IPPROTO_UDP:
403 			ret = i40e_add_del_fdir_udpv4(vsi, input,
404 						      raw_packet, add);
405 			break;
406 		case IPPROTO_SCTP:
407 			ret = i40e_add_del_fdir_sctpv4(vsi, input,
408 						       raw_packet, add);
409 			break;
410 		default:
411 			ret = i40e_add_del_fdir_ipv4(vsi, input,
412 						     raw_packet, add);
413 			break;
414 		}
415 		break;
416 	default:
417 		dev_info(&pf->pdev->dev, "Could not specify spec type %d\n",
418 			 input->flow_type);
419 		ret = -EINVAL;
420 	}
421 
422 	kfree(raw_packet);
423 	return ret;
424 }
425 
426 /**
427  * i40e_fd_handle_status - check the Programming Status for FD
428  * @rx_ring: the Rx ring for this descriptor
429  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
430  * @prog_id: the id originally used for programming
431  *
432  * This is used to verify if the FD programming or invalidation
433  * requested by SW to the HW is successful or not and take actions accordingly.
434  **/
435 static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
436 				  union i40e_rx_desc *rx_desc, u8 prog_id)
437 {
438 	struct i40e_pf *pf = rx_ring->vsi->back;
439 	struct pci_dev *pdev = pf->pdev;
440 	u32 fcnt_prog, fcnt_avail;
441 	u32 error;
442 	u64 qw;
443 
444 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
445 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
446 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
447 
448 	if (error == (0x1 << I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
449 		dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
450 			 rx_desc->wb.qword0.hi_dword.fd_id);
451 
452 		/* filter programming failed most likely due to table full */
453 		fcnt_prog = i40e_get_current_fd_count(pf);
454 		fcnt_avail = i40e_get_fd_cnt_all(pf);
455 		/* If ATR is running fcnt_prog can quickly change,
456 		 * if we are very close to full, it makes sense to disable
457 		 * FD ATR/SB and then re-enable it when there is room.
458 		 */
459 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
460 			/* Turn off ATR first */
461 			if (pf->flags & I40E_FLAG_FD_ATR_ENABLED) {
462 				pf->flags &= ~I40E_FLAG_FD_ATR_ENABLED;
463 				dev_warn(&pdev->dev, "FD filter space full, ATR for further flows will be turned off\n");
464 				pf->auto_disable_flags |=
465 						       I40E_FLAG_FD_ATR_ENABLED;
466 				pf->flags |= I40E_FLAG_FDIR_REQUIRES_REINIT;
467 			} else if (pf->flags & I40E_FLAG_FD_SB_ENABLED) {
468 				pf->flags &= ~I40E_FLAG_FD_SB_ENABLED;
469 				dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
470 				pf->auto_disable_flags |=
471 							I40E_FLAG_FD_SB_ENABLED;
472 				pf->flags |= I40E_FLAG_FDIR_REQUIRES_REINIT;
473 			}
474 		} else {
475 			dev_info(&pdev->dev, "FD filter programming error\n");
476 		}
477 	} else if (error ==
478 			  (0x1 << I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
479 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
480 			dev_info(&pdev->dev, "ntuple filter loc = %d, could not be removed\n",
481 				 rx_desc->wb.qword0.hi_dword.fd_id);
482 	}
483 }
484 
485 /**
486  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
487  * @ring:      the ring that owns the buffer
488  * @tx_buffer: the buffer to free
489  **/
490 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
491 					    struct i40e_tx_buffer *tx_buffer)
492 {
493 	if (tx_buffer->skb) {
494 		dev_kfree_skb_any(tx_buffer->skb);
495 		if (dma_unmap_len(tx_buffer, len))
496 			dma_unmap_single(ring->dev,
497 					 dma_unmap_addr(tx_buffer, dma),
498 					 dma_unmap_len(tx_buffer, len),
499 					 DMA_TO_DEVICE);
500 	} else if (dma_unmap_len(tx_buffer, len)) {
501 		dma_unmap_page(ring->dev,
502 			       dma_unmap_addr(tx_buffer, dma),
503 			       dma_unmap_len(tx_buffer, len),
504 			       DMA_TO_DEVICE);
505 	}
506 	tx_buffer->next_to_watch = NULL;
507 	tx_buffer->skb = NULL;
508 	dma_unmap_len_set(tx_buffer, len, 0);
509 	/* tx_buffer must be completely set up in the transmit path */
510 }
511 
512 /**
513  * i40e_clean_tx_ring - Free any empty Tx buffers
514  * @tx_ring: ring to be cleaned
515  **/
516 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
517 {
518 	unsigned long bi_size;
519 	u16 i;
520 
521 	/* ring already cleared, nothing to do */
522 	if (!tx_ring->tx_bi)
523 		return;
524 
525 	/* Free all the Tx ring sk_buffs */
526 	for (i = 0; i < tx_ring->count; i++)
527 		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
528 
529 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
530 	memset(tx_ring->tx_bi, 0, bi_size);
531 
532 	/* Zero out the descriptor ring */
533 	memset(tx_ring->desc, 0, tx_ring->size);
534 
535 	tx_ring->next_to_use = 0;
536 	tx_ring->next_to_clean = 0;
537 
538 	if (!tx_ring->netdev)
539 		return;
540 
541 	/* cleanup Tx queue statistics */
542 	netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
543 						  tx_ring->queue_index));
544 }
545 
546 /**
547  * i40e_free_tx_resources - Free Tx resources per queue
548  * @tx_ring: Tx descriptor ring for a specific queue
549  *
550  * Free all transmit software resources
551  **/
552 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
553 {
554 	i40e_clean_tx_ring(tx_ring);
555 	kfree(tx_ring->tx_bi);
556 	tx_ring->tx_bi = NULL;
557 
558 	if (tx_ring->desc) {
559 		dma_free_coherent(tx_ring->dev, tx_ring->size,
560 				  tx_ring->desc, tx_ring->dma);
561 		tx_ring->desc = NULL;
562 	}
563 }
564 
565 /**
566  * i40e_get_tx_pending - how many tx descriptors not processed
567  * @tx_ring: the ring of descriptors
568  *
569  * Since there is no access to the ring head register
570  * in XL710, we need to use our local copies
571  **/
572 static u32 i40e_get_tx_pending(struct i40e_ring *ring)
573 {
574 	u32 ntu = ((ring->next_to_clean <= ring->next_to_use)
575 			? ring->next_to_use
576 			: ring->next_to_use + ring->count);
577 	return ntu - ring->next_to_clean;
578 }
579 
580 /**
581  * i40e_check_tx_hang - Is there a hang in the Tx queue
582  * @tx_ring: the ring of descriptors
583  **/
584 static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
585 {
586 	u32 tx_pending = i40e_get_tx_pending(tx_ring);
587 	bool ret = false;
588 
589 	clear_check_for_tx_hang(tx_ring);
590 
591 	/* Check for a hung queue, but be thorough. This verifies
592 	 * that a transmit has been completed since the previous
593 	 * check AND there is at least one packet pending. The
594 	 * ARMED bit is set to indicate a potential hang. The
595 	 * bit is cleared if a pause frame is received to remove
596 	 * false hang detection due to PFC or 802.3x frames. By
597 	 * requiring this to fail twice we avoid races with
598 	 * PFC clearing the ARMED bit and conditions where we
599 	 * run the check_tx_hang logic with a transmit completion
600 	 * pending but without time to complete it yet.
601 	 */
602 	if ((tx_ring->tx_stats.tx_done_old == tx_ring->stats.packets) &&
603 	    tx_pending) {
604 		/* make sure it is true for two checks in a row */
605 		ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
606 				       &tx_ring->state);
607 	} else {
608 		/* update completed stats and disarm the hang check */
609 		tx_ring->tx_stats.tx_done_old = tx_ring->stats.packets;
610 		clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
611 	}
612 
613 	return ret;
614 }
615 
616 /**
617  * i40e_get_head - Retrieve head from head writeback
618  * @tx_ring:  tx ring to fetch head of
619  *
620  * Returns value of Tx ring head based on value stored
621  * in head write-back location
622  **/
623 static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
624 {
625 	void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
626 
627 	return le32_to_cpu(*(volatile __le32 *)head);
628 }
629 
630 /**
631  * i40e_clean_tx_irq - Reclaim resources after transmit completes
632  * @tx_ring:  tx ring to clean
633  * @budget:   how many cleans we're allowed
634  *
635  * Returns true if there's any budget left (e.g. the clean is finished)
636  **/
637 static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
638 {
639 	u16 i = tx_ring->next_to_clean;
640 	struct i40e_tx_buffer *tx_buf;
641 	struct i40e_tx_desc *tx_head;
642 	struct i40e_tx_desc *tx_desc;
643 	unsigned int total_packets = 0;
644 	unsigned int total_bytes = 0;
645 
646 	tx_buf = &tx_ring->tx_bi[i];
647 	tx_desc = I40E_TX_DESC(tx_ring, i);
648 	i -= tx_ring->count;
649 
650 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
651 
652 	do {
653 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
654 
655 		/* if next_to_watch is not set then there is no work pending */
656 		if (!eop_desc)
657 			break;
658 
659 		/* prevent any other reads prior to eop_desc */
660 		read_barrier_depends();
661 
662 		/* we have caught up to head, no work left to do */
663 		if (tx_head == tx_desc)
664 			break;
665 
666 		/* clear next_to_watch to prevent false hangs */
667 		tx_buf->next_to_watch = NULL;
668 
669 		/* update the statistics for this packet */
670 		total_bytes += tx_buf->bytecount;
671 		total_packets += tx_buf->gso_segs;
672 
673 		/* free the skb */
674 		dev_kfree_skb_any(tx_buf->skb);
675 
676 		/* unmap skb header data */
677 		dma_unmap_single(tx_ring->dev,
678 				 dma_unmap_addr(tx_buf, dma),
679 				 dma_unmap_len(tx_buf, len),
680 				 DMA_TO_DEVICE);
681 
682 		/* clear tx_buffer data */
683 		tx_buf->skb = NULL;
684 		dma_unmap_len_set(tx_buf, len, 0);
685 
686 		/* unmap remaining buffers */
687 		while (tx_desc != eop_desc) {
688 
689 			tx_buf++;
690 			tx_desc++;
691 			i++;
692 			if (unlikely(!i)) {
693 				i -= tx_ring->count;
694 				tx_buf = tx_ring->tx_bi;
695 				tx_desc = I40E_TX_DESC(tx_ring, 0);
696 			}
697 
698 			/* unmap any remaining paged data */
699 			if (dma_unmap_len(tx_buf, len)) {
700 				dma_unmap_page(tx_ring->dev,
701 					       dma_unmap_addr(tx_buf, dma),
702 					       dma_unmap_len(tx_buf, len),
703 					       DMA_TO_DEVICE);
704 				dma_unmap_len_set(tx_buf, len, 0);
705 			}
706 		}
707 
708 		/* move us one more past the eop_desc for start of next pkt */
709 		tx_buf++;
710 		tx_desc++;
711 		i++;
712 		if (unlikely(!i)) {
713 			i -= tx_ring->count;
714 			tx_buf = tx_ring->tx_bi;
715 			tx_desc = I40E_TX_DESC(tx_ring, 0);
716 		}
717 
718 		/* update budget accounting */
719 		budget--;
720 	} while (likely(budget));
721 
722 	i += tx_ring->count;
723 	tx_ring->next_to_clean = i;
724 	u64_stats_update_begin(&tx_ring->syncp);
725 	tx_ring->stats.bytes += total_bytes;
726 	tx_ring->stats.packets += total_packets;
727 	u64_stats_update_end(&tx_ring->syncp);
728 	tx_ring->q_vector->tx.total_bytes += total_bytes;
729 	tx_ring->q_vector->tx.total_packets += total_packets;
730 
731 	if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
732 		/* schedule immediate reset if we believe we hung */
733 		dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
734 			 "  VSI                  <%d>\n"
735 			 "  Tx Queue             <%d>\n"
736 			 "  next_to_use          <%x>\n"
737 			 "  next_to_clean        <%x>\n",
738 			 tx_ring->vsi->seid,
739 			 tx_ring->queue_index,
740 			 tx_ring->next_to_use, i);
741 		dev_info(tx_ring->dev, "tx_bi[next_to_clean]\n"
742 			 "  time_stamp           <%lx>\n"
743 			 "  jiffies              <%lx>\n",
744 			 tx_ring->tx_bi[i].time_stamp, jiffies);
745 
746 		netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
747 
748 		dev_info(tx_ring->dev,
749 			 "tx hang detected on queue %d, resetting adapter\n",
750 			 tx_ring->queue_index);
751 
752 		tx_ring->netdev->netdev_ops->ndo_tx_timeout(tx_ring->netdev);
753 
754 		/* the adapter is about to reset, no point in enabling stuff */
755 		return true;
756 	}
757 
758 	netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
759 						      tx_ring->queue_index),
760 				  total_packets, total_bytes);
761 
762 #define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
763 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
764 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
765 		/* Make sure that anybody stopping the queue after this
766 		 * sees the new next_to_clean.
767 		 */
768 		smp_mb();
769 		if (__netif_subqueue_stopped(tx_ring->netdev,
770 					     tx_ring->queue_index) &&
771 		   !test_bit(__I40E_DOWN, &tx_ring->vsi->state)) {
772 			netif_wake_subqueue(tx_ring->netdev,
773 					    tx_ring->queue_index);
774 			++tx_ring->tx_stats.restart_queue;
775 		}
776 	}
777 
778 	return budget > 0;
779 }
780 
781 /**
782  * i40e_set_new_dynamic_itr - Find new ITR level
783  * @rc: structure containing ring performance data
784  *
785  * Stores a new ITR value based on packets and byte counts during
786  * the last interrupt.  The advantage of per interrupt computation
787  * is faster updates and more accurate ITR for the current traffic
788  * pattern.  Constants in this function were computed based on
789  * theoretical maximum wire speed and thresholds were set based on
790  * testing data as well as attempting to minimize response time
791  * while increasing bulk throughput.
792  **/
793 static void i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
794 {
795 	enum i40e_latency_range new_latency_range = rc->latency_range;
796 	u32 new_itr = rc->itr;
797 	int bytes_per_int;
798 
799 	if (rc->total_packets == 0 || !rc->itr)
800 		return;
801 
802 	/* simple throttlerate management
803 	 *   0-10MB/s   lowest (100000 ints/s)
804 	 *  10-20MB/s   low    (20000 ints/s)
805 	 *  20-1249MB/s bulk   (8000 ints/s)
806 	 */
807 	bytes_per_int = rc->total_bytes / rc->itr;
808 	switch (rc->itr) {
809 	case I40E_LOWEST_LATENCY:
810 		if (bytes_per_int > 10)
811 			new_latency_range = I40E_LOW_LATENCY;
812 		break;
813 	case I40E_LOW_LATENCY:
814 		if (bytes_per_int > 20)
815 			new_latency_range = I40E_BULK_LATENCY;
816 		else if (bytes_per_int <= 10)
817 			new_latency_range = I40E_LOWEST_LATENCY;
818 		break;
819 	case I40E_BULK_LATENCY:
820 		if (bytes_per_int <= 20)
821 			rc->latency_range = I40E_LOW_LATENCY;
822 		break;
823 	}
824 
825 	switch (new_latency_range) {
826 	case I40E_LOWEST_LATENCY:
827 		new_itr = I40E_ITR_100K;
828 		break;
829 	case I40E_LOW_LATENCY:
830 		new_itr = I40E_ITR_20K;
831 		break;
832 	case I40E_BULK_LATENCY:
833 		new_itr = I40E_ITR_8K;
834 		break;
835 	default:
836 		break;
837 	}
838 
839 	if (new_itr != rc->itr) {
840 		/* do an exponential smoothing */
841 		new_itr = (10 * new_itr * rc->itr) /
842 			  ((9 * new_itr) + rc->itr);
843 		rc->itr = new_itr & I40E_MAX_ITR;
844 	}
845 
846 	rc->total_bytes = 0;
847 	rc->total_packets = 0;
848 }
849 
850 /**
851  * i40e_update_dynamic_itr - Adjust ITR based on bytes per int
852  * @q_vector: the vector to adjust
853  **/
854 static void i40e_update_dynamic_itr(struct i40e_q_vector *q_vector)
855 {
856 	u16 vector = q_vector->vsi->base_vector + q_vector->v_idx;
857 	struct i40e_hw *hw = &q_vector->vsi->back->hw;
858 	u32 reg_addr;
859 	u16 old_itr;
860 
861 	reg_addr = I40E_PFINT_ITRN(I40E_RX_ITR, vector - 1);
862 	old_itr = q_vector->rx.itr;
863 	i40e_set_new_dynamic_itr(&q_vector->rx);
864 	if (old_itr != q_vector->rx.itr)
865 		wr32(hw, reg_addr, q_vector->rx.itr);
866 
867 	reg_addr = I40E_PFINT_ITRN(I40E_TX_ITR, vector - 1);
868 	old_itr = q_vector->tx.itr;
869 	i40e_set_new_dynamic_itr(&q_vector->tx);
870 	if (old_itr != q_vector->tx.itr)
871 		wr32(hw, reg_addr, q_vector->tx.itr);
872 }
873 
874 /**
875  * i40e_clean_programming_status - clean the programming status descriptor
876  * @rx_ring: the rx ring that has this descriptor
877  * @rx_desc: the rx descriptor written back by HW
878  *
879  * Flow director should handle FD_FILTER_STATUS to check its filter programming
880  * status being successful or not and take actions accordingly. FCoE should
881  * handle its context/filter programming/invalidation status and take actions.
882  *
883  **/
884 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
885 					  union i40e_rx_desc *rx_desc)
886 {
887 	u64 qw;
888 	u8 id;
889 
890 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
891 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
892 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
893 
894 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
895 		i40e_fd_handle_status(rx_ring, rx_desc, id);
896 }
897 
898 /**
899  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
900  * @tx_ring: the tx ring to set up
901  *
902  * Return 0 on success, negative on error
903  **/
904 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
905 {
906 	struct device *dev = tx_ring->dev;
907 	int bi_size;
908 
909 	if (!dev)
910 		return -ENOMEM;
911 
912 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
913 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
914 	if (!tx_ring->tx_bi)
915 		goto err;
916 
917 	/* round up to nearest 4K */
918 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
919 	/* add u32 for head writeback, align after this takes care of
920 	 * guaranteeing this is at least one cache line in size
921 	 */
922 	tx_ring->size += sizeof(u32);
923 	tx_ring->size = ALIGN(tx_ring->size, 4096);
924 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
925 					   &tx_ring->dma, GFP_KERNEL);
926 	if (!tx_ring->desc) {
927 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
928 			 tx_ring->size);
929 		goto err;
930 	}
931 
932 	tx_ring->next_to_use = 0;
933 	tx_ring->next_to_clean = 0;
934 	return 0;
935 
936 err:
937 	kfree(tx_ring->tx_bi);
938 	tx_ring->tx_bi = NULL;
939 	return -ENOMEM;
940 }
941 
942 /**
943  * i40e_clean_rx_ring - Free Rx buffers
944  * @rx_ring: ring to be cleaned
945  **/
946 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
947 {
948 	struct device *dev = rx_ring->dev;
949 	struct i40e_rx_buffer *rx_bi;
950 	unsigned long bi_size;
951 	u16 i;
952 
953 	/* ring already cleared, nothing to do */
954 	if (!rx_ring->rx_bi)
955 		return;
956 
957 	/* Free all the Rx ring sk_buffs */
958 	for (i = 0; i < rx_ring->count; i++) {
959 		rx_bi = &rx_ring->rx_bi[i];
960 		if (rx_bi->dma) {
961 			dma_unmap_single(dev,
962 					 rx_bi->dma,
963 					 rx_ring->rx_buf_len,
964 					 DMA_FROM_DEVICE);
965 			rx_bi->dma = 0;
966 		}
967 		if (rx_bi->skb) {
968 			dev_kfree_skb(rx_bi->skb);
969 			rx_bi->skb = NULL;
970 		}
971 		if (rx_bi->page) {
972 			if (rx_bi->page_dma) {
973 				dma_unmap_page(dev,
974 					       rx_bi->page_dma,
975 					       PAGE_SIZE / 2,
976 					       DMA_FROM_DEVICE);
977 				rx_bi->page_dma = 0;
978 			}
979 			__free_page(rx_bi->page);
980 			rx_bi->page = NULL;
981 			rx_bi->page_offset = 0;
982 		}
983 	}
984 
985 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
986 	memset(rx_ring->rx_bi, 0, bi_size);
987 
988 	/* Zero out the descriptor ring */
989 	memset(rx_ring->desc, 0, rx_ring->size);
990 
991 	rx_ring->next_to_clean = 0;
992 	rx_ring->next_to_use = 0;
993 }
994 
995 /**
996  * i40e_free_rx_resources - Free Rx resources
997  * @rx_ring: ring to clean the resources from
998  *
999  * Free all receive software resources
1000  **/
1001 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1002 {
1003 	i40e_clean_rx_ring(rx_ring);
1004 	kfree(rx_ring->rx_bi);
1005 	rx_ring->rx_bi = NULL;
1006 
1007 	if (rx_ring->desc) {
1008 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1009 				  rx_ring->desc, rx_ring->dma);
1010 		rx_ring->desc = NULL;
1011 	}
1012 }
1013 
1014 /**
1015  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1016  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1017  *
1018  * Returns 0 on success, negative on failure
1019  **/
1020 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1021 {
1022 	struct device *dev = rx_ring->dev;
1023 	int bi_size;
1024 
1025 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1026 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1027 	if (!rx_ring->rx_bi)
1028 		goto err;
1029 
1030 	/* Round up to nearest 4K */
1031 	rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
1032 		? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
1033 		: rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1034 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1035 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1036 					   &rx_ring->dma, GFP_KERNEL);
1037 
1038 	if (!rx_ring->desc) {
1039 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1040 			 rx_ring->size);
1041 		goto err;
1042 	}
1043 
1044 	rx_ring->next_to_clean = 0;
1045 	rx_ring->next_to_use = 0;
1046 
1047 	return 0;
1048 err:
1049 	kfree(rx_ring->rx_bi);
1050 	rx_ring->rx_bi = NULL;
1051 	return -ENOMEM;
1052 }
1053 
1054 /**
1055  * i40e_release_rx_desc - Store the new tail and head values
1056  * @rx_ring: ring to bump
1057  * @val: new head index
1058  **/
1059 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1060 {
1061 	rx_ring->next_to_use = val;
1062 	/* Force memory writes to complete before letting h/w
1063 	 * know there are new descriptors to fetch.  (Only
1064 	 * applicable for weak-ordered memory model archs,
1065 	 * such as IA-64).
1066 	 */
1067 	wmb();
1068 	writel(val, rx_ring->tail);
1069 }
1070 
1071 /**
1072  * i40e_alloc_rx_buffers - Replace used receive buffers; packet split
1073  * @rx_ring: ring to place buffers on
1074  * @cleaned_count: number of buffers to replace
1075  **/
1076 void i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1077 {
1078 	u16 i = rx_ring->next_to_use;
1079 	union i40e_rx_desc *rx_desc;
1080 	struct i40e_rx_buffer *bi;
1081 	struct sk_buff *skb;
1082 
1083 	/* do nothing if no valid netdev defined */
1084 	if (!rx_ring->netdev || !cleaned_count)
1085 		return;
1086 
1087 	while (cleaned_count--) {
1088 		rx_desc = I40E_RX_DESC(rx_ring, i);
1089 		bi = &rx_ring->rx_bi[i];
1090 		skb = bi->skb;
1091 
1092 		if (!skb) {
1093 			skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
1094 							rx_ring->rx_buf_len);
1095 			if (!skb) {
1096 				rx_ring->rx_stats.alloc_buff_failed++;
1097 				goto no_buffers;
1098 			}
1099 			/* initialize queue mapping */
1100 			skb_record_rx_queue(skb, rx_ring->queue_index);
1101 			bi->skb = skb;
1102 		}
1103 
1104 		if (!bi->dma) {
1105 			bi->dma = dma_map_single(rx_ring->dev,
1106 						 skb->data,
1107 						 rx_ring->rx_buf_len,
1108 						 DMA_FROM_DEVICE);
1109 			if (dma_mapping_error(rx_ring->dev, bi->dma)) {
1110 				rx_ring->rx_stats.alloc_buff_failed++;
1111 				bi->dma = 0;
1112 				goto no_buffers;
1113 			}
1114 		}
1115 
1116 		if (ring_is_ps_enabled(rx_ring)) {
1117 			if (!bi->page) {
1118 				bi->page = alloc_page(GFP_ATOMIC);
1119 				if (!bi->page) {
1120 					rx_ring->rx_stats.alloc_page_failed++;
1121 					goto no_buffers;
1122 				}
1123 			}
1124 
1125 			if (!bi->page_dma) {
1126 				/* use a half page if we're re-using */
1127 				bi->page_offset ^= PAGE_SIZE / 2;
1128 				bi->page_dma = dma_map_page(rx_ring->dev,
1129 							    bi->page,
1130 							    bi->page_offset,
1131 							    PAGE_SIZE / 2,
1132 							    DMA_FROM_DEVICE);
1133 				if (dma_mapping_error(rx_ring->dev,
1134 						      bi->page_dma)) {
1135 					rx_ring->rx_stats.alloc_page_failed++;
1136 					bi->page_dma = 0;
1137 					goto no_buffers;
1138 				}
1139 			}
1140 
1141 			/* Refresh the desc even if buffer_addrs didn't change
1142 			 * because each write-back erases this info.
1143 			 */
1144 			rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
1145 			rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
1146 		} else {
1147 			rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
1148 			rx_desc->read.hdr_addr = 0;
1149 		}
1150 		i++;
1151 		if (i == rx_ring->count)
1152 			i = 0;
1153 	}
1154 
1155 no_buffers:
1156 	if (rx_ring->next_to_use != i)
1157 		i40e_release_rx_desc(rx_ring, i);
1158 }
1159 
1160 /**
1161  * i40e_receive_skb - Send a completed packet up the stack
1162  * @rx_ring:  rx ring in play
1163  * @skb: packet to send up
1164  * @vlan_tag: vlan tag for packet
1165  **/
1166 static void i40e_receive_skb(struct i40e_ring *rx_ring,
1167 			     struct sk_buff *skb, u16 vlan_tag)
1168 {
1169 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1170 	struct i40e_vsi *vsi = rx_ring->vsi;
1171 	u64 flags = vsi->back->flags;
1172 
1173 	if (vlan_tag & VLAN_VID_MASK)
1174 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1175 
1176 	if (flags & I40E_FLAG_IN_NETPOLL)
1177 		netif_rx(skb);
1178 	else
1179 		napi_gro_receive(&q_vector->napi, skb);
1180 }
1181 
1182 /**
1183  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1184  * @vsi: the VSI we care about
1185  * @skb: skb currently being received and modified
1186  * @rx_status: status value of last descriptor in packet
1187  * @rx_error: error value of last descriptor in packet
1188  * @rx_ptype: ptype value of last descriptor in packet
1189  **/
1190 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1191 				    struct sk_buff *skb,
1192 				    u32 rx_status,
1193 				    u32 rx_error,
1194 				    u16 rx_ptype)
1195 {
1196 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(rx_ptype);
1197 	bool ipv4 = false, ipv6 = false;
1198 	bool ipv4_tunnel, ipv6_tunnel;
1199 	__wsum rx_udp_csum;
1200 	struct iphdr *iph;
1201 	__sum16 csum;
1202 
1203 	ipv4_tunnel = (rx_ptype > I40E_RX_PTYPE_GRENAT4_MAC_PAY3) &&
1204 		      (rx_ptype < I40E_RX_PTYPE_GRENAT4_MACVLAN_IPV6_ICMP_PAY4);
1205 	ipv6_tunnel = (rx_ptype > I40E_RX_PTYPE_GRENAT6_MAC_PAY3) &&
1206 		      (rx_ptype < I40E_RX_PTYPE_GRENAT6_MACVLAN_IPV6_ICMP_PAY4);
1207 
1208 	skb->encapsulation = ipv4_tunnel || ipv6_tunnel;
1209 	skb->ip_summed = CHECKSUM_NONE;
1210 
1211 	/* Rx csum enabled and ip headers found? */
1212 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1213 		return;
1214 
1215 	/* did the hardware decode the packet and checksum? */
1216 	if (!(rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1217 		return;
1218 
1219 	/* both known and outer_ip must be set for the below code to work */
1220 	if (!(decoded.known && decoded.outer_ip))
1221 		return;
1222 
1223 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1224 	    decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4)
1225 		ipv4 = true;
1226 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1227 		 decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6)
1228 		ipv6 = true;
1229 
1230 	if (ipv4 &&
1231 	    (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) |
1232 			 (1 << I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1233 		goto checksum_fail;
1234 
1235 	/* likely incorrect csum if alternate IP extension headers found */
1236 	if (ipv6 &&
1237 	    decoded.inner_prot == I40E_RX_PTYPE_INNER_PROT_TCP &&
1238 	    rx_error & (1 << I40E_RX_DESC_ERROR_L4E_SHIFT) &&
1239 	    rx_status & (1 << I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1240 		/* don't increment checksum err here, non-fatal err */
1241 		return;
1242 
1243 	/* there was some L4 error, count error and punt packet to the stack */
1244 	if (rx_error & (1 << I40E_RX_DESC_ERROR_L4E_SHIFT))
1245 		goto checksum_fail;
1246 
1247 	/* handle packets that were not able to be checksummed due
1248 	 * to arrival speed, in this case the stack can compute
1249 	 * the csum.
1250 	 */
1251 	if (rx_error & (1 << I40E_RX_DESC_ERROR_PPRS_SHIFT))
1252 		return;
1253 
1254 	/* If VXLAN traffic has an outer UDPv4 checksum we need to check
1255 	 * it in the driver, hardware does not do it for us.
1256 	 * Since L3L4P bit was set we assume a valid IHL value (>=5)
1257 	 * so the total length of IPv4 header is IHL*4 bytes
1258 	 * The UDP_0 bit *may* bet set if the *inner* header is UDP
1259 	 */
1260 	if (ipv4_tunnel &&
1261 	    (decoded.inner_prot != I40E_RX_PTYPE_INNER_PROT_UDP) &&
1262 	    !(rx_status & (1 << I40E_RX_DESC_STATUS_UDP_0_SHIFT))) {
1263 		skb->transport_header = skb->mac_header +
1264 					sizeof(struct ethhdr) +
1265 					(ip_hdr(skb)->ihl * 4);
1266 
1267 		/* Add 4 bytes for VLAN tagged packets */
1268 		skb->transport_header += (skb->protocol == htons(ETH_P_8021Q) ||
1269 					  skb->protocol == htons(ETH_P_8021AD))
1270 					  ? VLAN_HLEN : 0;
1271 
1272 		rx_udp_csum = udp_csum(skb);
1273 		iph = ip_hdr(skb);
1274 		csum = csum_tcpudp_magic(
1275 				iph->saddr, iph->daddr,
1276 				(skb->len - skb_transport_offset(skb)),
1277 				IPPROTO_UDP, rx_udp_csum);
1278 
1279 		if (udp_hdr(skb)->check != csum)
1280 			goto checksum_fail;
1281 	}
1282 
1283 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1284 
1285 	return;
1286 
1287 checksum_fail:
1288 	vsi->back->hw_csum_rx_error++;
1289 }
1290 
1291 /**
1292  * i40e_rx_hash - returns the hash value from the Rx descriptor
1293  * @ring: descriptor ring
1294  * @rx_desc: specific descriptor
1295  **/
1296 static inline u32 i40e_rx_hash(struct i40e_ring *ring,
1297 			       union i40e_rx_desc *rx_desc)
1298 {
1299 	const __le64 rss_mask =
1300 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1301 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1302 
1303 	if ((ring->netdev->features & NETIF_F_RXHASH) &&
1304 	    (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
1305 		return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1306 	else
1307 		return 0;
1308 }
1309 
1310 /**
1311  * i40e_ptype_to_hash - get a hash type
1312  * @ptype: the ptype value from the descriptor
1313  *
1314  * Returns a hash type to be used by skb_set_hash
1315  **/
1316 static inline enum pkt_hash_types i40e_ptype_to_hash(u8 ptype)
1317 {
1318 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1319 
1320 	if (!decoded.known)
1321 		return PKT_HASH_TYPE_NONE;
1322 
1323 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1324 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1325 		return PKT_HASH_TYPE_L4;
1326 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1327 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1328 		return PKT_HASH_TYPE_L3;
1329 	else
1330 		return PKT_HASH_TYPE_L2;
1331 }
1332 
1333 /**
1334  * i40e_clean_rx_irq - Reclaim resources after receive completes
1335  * @rx_ring:  rx ring to clean
1336  * @budget:   how many cleans we're allowed
1337  *
1338  * Returns true if there's any budget left (e.g. the clean is finished)
1339  **/
1340 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
1341 {
1342 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1343 	u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
1344 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1345 	const int current_node = numa_node_id();
1346 	struct i40e_vsi *vsi = rx_ring->vsi;
1347 	u16 i = rx_ring->next_to_clean;
1348 	union i40e_rx_desc *rx_desc;
1349 	u32 rx_error, rx_status;
1350 	u8 rx_ptype;
1351 	u64 qword;
1352 
1353 	if (budget <= 0)
1354 		return 0;
1355 
1356 	rx_desc = I40E_RX_DESC(rx_ring, i);
1357 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1358 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1359 		    I40E_RXD_QW1_STATUS_SHIFT;
1360 
1361 	while (rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)) {
1362 		union i40e_rx_desc *next_rxd;
1363 		struct i40e_rx_buffer *rx_bi;
1364 		struct sk_buff *skb;
1365 		u16 vlan_tag;
1366 		if (i40e_rx_is_programming_status(qword)) {
1367 			i40e_clean_programming_status(rx_ring, rx_desc);
1368 			I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
1369 			goto next_desc;
1370 		}
1371 		rx_bi = &rx_ring->rx_bi[i];
1372 		skb = rx_bi->skb;
1373 		prefetch(skb->data);
1374 
1375 		rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
1376 				I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
1377 		rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK) >>
1378 				I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
1379 		rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK) >>
1380 			 I40E_RXD_QW1_LENGTH_SPH_SHIFT;
1381 
1382 		rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1383 			   I40E_RXD_QW1_ERROR_SHIFT;
1384 		rx_hbo = rx_error & (1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1385 		rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1386 
1387 		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1388 			   I40E_RXD_QW1_PTYPE_SHIFT;
1389 		rx_bi->skb = NULL;
1390 
1391 		/* This memory barrier is needed to keep us from reading
1392 		 * any other fields out of the rx_desc until we know the
1393 		 * STATUS_DD bit is set
1394 		 */
1395 		rmb();
1396 
1397 		/* Get the header and possibly the whole packet
1398 		 * If this is an skb from previous receive dma will be 0
1399 		 */
1400 		if (rx_bi->dma) {
1401 			u16 len;
1402 
1403 			if (rx_hbo)
1404 				len = I40E_RX_HDR_SIZE;
1405 			else if (rx_sph)
1406 				len = rx_header_len;
1407 			else if (rx_packet_len)
1408 				len = rx_packet_len;   /* 1buf/no split found */
1409 			else
1410 				len = rx_header_len;   /* split always mode */
1411 
1412 			skb_put(skb, len);
1413 			dma_unmap_single(rx_ring->dev,
1414 					 rx_bi->dma,
1415 					 rx_ring->rx_buf_len,
1416 					 DMA_FROM_DEVICE);
1417 			rx_bi->dma = 0;
1418 		}
1419 
1420 		/* Get the rest of the data if this was a header split */
1421 		if (ring_is_ps_enabled(rx_ring) && rx_packet_len) {
1422 
1423 			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
1424 					   rx_bi->page,
1425 					   rx_bi->page_offset,
1426 					   rx_packet_len);
1427 
1428 			skb->len += rx_packet_len;
1429 			skb->data_len += rx_packet_len;
1430 			skb->truesize += rx_packet_len;
1431 
1432 			if ((page_count(rx_bi->page) == 1) &&
1433 			    (page_to_nid(rx_bi->page) == current_node))
1434 				get_page(rx_bi->page);
1435 			else
1436 				rx_bi->page = NULL;
1437 
1438 			dma_unmap_page(rx_ring->dev,
1439 				       rx_bi->page_dma,
1440 				       PAGE_SIZE / 2,
1441 				       DMA_FROM_DEVICE);
1442 			rx_bi->page_dma = 0;
1443 		}
1444 		I40E_RX_NEXT_DESC_PREFETCH(rx_ring, i, next_rxd);
1445 
1446 		if (unlikely(
1447 		    !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1448 			struct i40e_rx_buffer *next_buffer;
1449 
1450 			next_buffer = &rx_ring->rx_bi[i];
1451 
1452 			if (ring_is_ps_enabled(rx_ring)) {
1453 				rx_bi->skb = next_buffer->skb;
1454 				rx_bi->dma = next_buffer->dma;
1455 				next_buffer->skb = skb;
1456 				next_buffer->dma = 0;
1457 			}
1458 			rx_ring->rx_stats.non_eop_descs++;
1459 			goto next_desc;
1460 		}
1461 
1462 		/* ERR_MASK will only have valid bits if EOP set */
1463 		if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1464 			dev_kfree_skb_any(skb);
1465 			/* TODO: shouldn't we increment a counter indicating the
1466 			 * drop?
1467 			 */
1468 			goto next_desc;
1469 		}
1470 
1471 		skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1472 			     i40e_ptype_to_hash(rx_ptype));
1473 		if (unlikely(rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK)) {
1474 			i40e_ptp_rx_hwtstamp(vsi->back, skb, (rx_status &
1475 					   I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1476 					   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT);
1477 			rx_ring->last_rx_timestamp = jiffies;
1478 		}
1479 
1480 		/* probably a little skewed due to removing CRC */
1481 		total_rx_bytes += skb->len;
1482 		total_rx_packets++;
1483 
1484 		skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1485 
1486 		i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1487 
1488 		vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1489 			 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1490 			 : 0;
1491 		i40e_receive_skb(rx_ring, skb, vlan_tag);
1492 
1493 		rx_ring->netdev->last_rx = jiffies;
1494 		budget--;
1495 next_desc:
1496 		rx_desc->wb.qword1.status_error_len = 0;
1497 		if (!budget)
1498 			break;
1499 
1500 		cleaned_count++;
1501 		/* return some buffers to hardware, one at a time is too slow */
1502 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1503 			i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1504 			cleaned_count = 0;
1505 		}
1506 
1507 		/* use prefetched values */
1508 		rx_desc = next_rxd;
1509 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1510 		rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1511 			    I40E_RXD_QW1_STATUS_SHIFT;
1512 	}
1513 
1514 	rx_ring->next_to_clean = i;
1515 	u64_stats_update_begin(&rx_ring->syncp);
1516 	rx_ring->stats.packets += total_rx_packets;
1517 	rx_ring->stats.bytes += total_rx_bytes;
1518 	u64_stats_update_end(&rx_ring->syncp);
1519 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
1520 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1521 
1522 	if (cleaned_count)
1523 		i40e_alloc_rx_buffers(rx_ring, cleaned_count);
1524 
1525 	return budget > 0;
1526 }
1527 
1528 /**
1529  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
1530  * @napi: napi struct with our devices info in it
1531  * @budget: amount of work driver is allowed to do this pass, in packets
1532  *
1533  * This function will clean all queues associated with a q_vector.
1534  *
1535  * Returns the amount of work done
1536  **/
1537 int i40e_napi_poll(struct napi_struct *napi, int budget)
1538 {
1539 	struct i40e_q_vector *q_vector =
1540 			       container_of(napi, struct i40e_q_vector, napi);
1541 	struct i40e_vsi *vsi = q_vector->vsi;
1542 	struct i40e_ring *ring;
1543 	bool clean_complete = true;
1544 	int budget_per_ring;
1545 
1546 	if (test_bit(__I40E_DOWN, &vsi->state)) {
1547 		napi_complete(napi);
1548 		return 0;
1549 	}
1550 
1551 	/* Since the actual Tx work is minimal, we can give the Tx a larger
1552 	 * budget and be more aggressive about cleaning up the Tx descriptors.
1553 	 */
1554 	i40e_for_each_ring(ring, q_vector->tx)
1555 		clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
1556 
1557 	/* We attempt to distribute budget to each Rx queue fairly, but don't
1558 	 * allow the budget to go below 1 because that would exit polling early.
1559 	 */
1560 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
1561 
1562 	i40e_for_each_ring(ring, q_vector->rx)
1563 		clean_complete &= i40e_clean_rx_irq(ring, budget_per_ring);
1564 
1565 	/* If work not completed, return budget and polling will return */
1566 	if (!clean_complete)
1567 		return budget;
1568 
1569 	/* Work is done so exit the polling mode and re-enable the interrupt */
1570 	napi_complete(napi);
1571 	if (ITR_IS_DYNAMIC(vsi->rx_itr_setting) ||
1572 	    ITR_IS_DYNAMIC(vsi->tx_itr_setting))
1573 		i40e_update_dynamic_itr(q_vector);
1574 
1575 	if (!test_bit(__I40E_DOWN, &vsi->state)) {
1576 		if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
1577 			i40e_irq_dynamic_enable(vsi,
1578 					q_vector->v_idx + vsi->base_vector);
1579 		} else {
1580 			struct i40e_hw *hw = &vsi->back->hw;
1581 			/* We re-enable the queue 0 cause, but
1582 			 * don't worry about dynamic_enable
1583 			 * because we left it on for the other
1584 			 * possible interrupts during napi
1585 			 */
1586 			u32 qval = rd32(hw, I40E_QINT_RQCTL(0));
1587 			qval |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
1588 			wr32(hw, I40E_QINT_RQCTL(0), qval);
1589 
1590 			qval = rd32(hw, I40E_QINT_TQCTL(0));
1591 			qval |= I40E_QINT_TQCTL_CAUSE_ENA_MASK;
1592 			wr32(hw, I40E_QINT_TQCTL(0), qval);
1593 
1594 			i40e_irq_dynamic_enable_icr0(vsi->back);
1595 		}
1596 	}
1597 
1598 	return 0;
1599 }
1600 
1601 /**
1602  * i40e_atr - Add a Flow Director ATR filter
1603  * @tx_ring:  ring to add programming descriptor to
1604  * @skb:      send buffer
1605  * @flags:    send flags
1606  * @protocol: wire protocol
1607  **/
1608 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
1609 		     u32 flags, __be16 protocol)
1610 {
1611 	struct i40e_filter_program_desc *fdir_desc;
1612 	struct i40e_pf *pf = tx_ring->vsi->back;
1613 	union {
1614 		unsigned char *network;
1615 		struct iphdr *ipv4;
1616 		struct ipv6hdr *ipv6;
1617 	} hdr;
1618 	struct tcphdr *th;
1619 	unsigned int hlen;
1620 	u32 flex_ptype, dtype_cmd;
1621 	u16 i;
1622 
1623 	/* make sure ATR is enabled */
1624 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
1625 		return;
1626 
1627 	/* if sampling is disabled do nothing */
1628 	if (!tx_ring->atr_sample_rate)
1629 		return;
1630 
1631 	/* snag network header to get L4 type and address */
1632 	hdr.network = skb_network_header(skb);
1633 
1634 	/* Currently only IPv4/IPv6 with TCP is supported */
1635 	if (protocol == htons(ETH_P_IP)) {
1636 		if (hdr.ipv4->protocol != IPPROTO_TCP)
1637 			return;
1638 
1639 		/* access ihl as a u8 to avoid unaligned access on ia64 */
1640 		hlen = (hdr.network[0] & 0x0F) << 2;
1641 	} else if (protocol == htons(ETH_P_IPV6)) {
1642 		if (hdr.ipv6->nexthdr != IPPROTO_TCP)
1643 			return;
1644 
1645 		hlen = sizeof(struct ipv6hdr);
1646 	} else {
1647 		return;
1648 	}
1649 
1650 	th = (struct tcphdr *)(hdr.network + hlen);
1651 
1652 	/* Due to lack of space, no more new filters can be programmed */
1653 	if (th->syn && (pf->auto_disable_flags & I40E_FLAG_FD_ATR_ENABLED))
1654 		return;
1655 
1656 	tx_ring->atr_count++;
1657 
1658 	/* sample on all syn/fin/rst packets or once every atr sample rate */
1659 	if (!th->fin &&
1660 	    !th->syn &&
1661 	    !th->rst &&
1662 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
1663 		return;
1664 
1665 	tx_ring->atr_count = 0;
1666 
1667 	/* grab the next descriptor */
1668 	i = tx_ring->next_to_use;
1669 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
1670 
1671 	i++;
1672 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1673 
1674 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
1675 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
1676 	flex_ptype |= (protocol == htons(ETH_P_IP)) ?
1677 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
1678 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
1679 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
1680 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
1681 
1682 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
1683 
1684 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
1685 
1686 	dtype_cmd |= (th->fin || th->rst) ?
1687 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
1688 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
1689 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
1690 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
1691 
1692 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
1693 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
1694 
1695 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
1696 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
1697 
1698 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
1699 	dtype_cmd |=
1700 		((u32)pf->fd_atr_cnt_idx << I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
1701 		I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
1702 
1703 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
1704 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
1705 }
1706 
1707 /**
1708  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
1709  * @skb:     send buffer
1710  * @tx_ring: ring to send buffer on
1711  * @flags:   the tx flags to be set
1712  *
1713  * Checks the skb and set up correspondingly several generic transmit flags
1714  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1715  *
1716  * Returns error code indicate the frame should be dropped upon error and the
1717  * otherwise  returns 0 to indicate the flags has been set properly.
1718  **/
1719 static int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
1720 				      struct i40e_ring *tx_ring,
1721 				      u32 *flags)
1722 {
1723 	__be16 protocol = skb->protocol;
1724 	u32  tx_flags = 0;
1725 
1726 	/* if we have a HW VLAN tag being added, default to the HW one */
1727 	if (vlan_tx_tag_present(skb)) {
1728 		tx_flags |= vlan_tx_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
1729 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1730 	/* else if it is a SW VLAN, check the next protocol and store the tag */
1731 	} else if (protocol == htons(ETH_P_8021Q)) {
1732 		struct vlan_hdr *vhdr, _vhdr;
1733 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
1734 		if (!vhdr)
1735 			return -EINVAL;
1736 
1737 		protocol = vhdr->h_vlan_encapsulated_proto;
1738 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
1739 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
1740 	}
1741 
1742 	/* Insert 802.1p priority into VLAN header */
1743 	if ((tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED) &&
1744 	    ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
1745 	     (skb->priority != TC_PRIO_CONTROL))) {
1746 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
1747 		tx_flags |= (skb->priority & 0x7) <<
1748 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
1749 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
1750 			struct vlan_ethhdr *vhdr;
1751 			int rc;
1752 
1753 			rc = skb_cow_head(skb, 0);
1754 			if (rc < 0)
1755 				return rc;
1756 			vhdr = (struct vlan_ethhdr *)skb->data;
1757 			vhdr->h_vlan_TCI = htons(tx_flags >>
1758 						 I40E_TX_FLAGS_VLAN_SHIFT);
1759 		} else {
1760 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
1761 		}
1762 	}
1763 	*flags = tx_flags;
1764 	return 0;
1765 }
1766 
1767 /**
1768  * i40e_tso - set up the tso context descriptor
1769  * @tx_ring:  ptr to the ring to send
1770  * @skb:      ptr to the skb we're sending
1771  * @tx_flags: the collected send information
1772  * @protocol: the send protocol
1773  * @hdr_len:  ptr to the size of the packet header
1774  * @cd_tunneling: ptr to context descriptor bits
1775  *
1776  * Returns 0 if no TSO can happen, 1 if tso is going, or error
1777  **/
1778 static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
1779 		    u32 tx_flags, __be16 protocol, u8 *hdr_len,
1780 		    u64 *cd_type_cmd_tso_mss, u32 *cd_tunneling)
1781 {
1782 	u32 cd_cmd, cd_tso_len, cd_mss;
1783 	struct ipv6hdr *ipv6h;
1784 	struct tcphdr *tcph;
1785 	struct iphdr *iph;
1786 	u32 l4len;
1787 	int err;
1788 
1789 	if (!skb_is_gso(skb))
1790 		return 0;
1791 
1792 	err = skb_cow_head(skb, 0);
1793 	if (err < 0)
1794 		return err;
1795 
1796 	if (protocol == htons(ETH_P_IP)) {
1797 		iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
1798 		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1799 		iph->tot_len = 0;
1800 		iph->check = 0;
1801 		tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
1802 						 0, IPPROTO_TCP, 0);
1803 	} else if (skb_is_gso_v6(skb)) {
1804 
1805 		ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb)
1806 					   : ipv6_hdr(skb);
1807 		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
1808 		ipv6h->payload_len = 0;
1809 		tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
1810 					       0, IPPROTO_TCP, 0);
1811 	}
1812 
1813 	l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
1814 	*hdr_len = (skb->encapsulation
1815 		    ? (skb_inner_transport_header(skb) - skb->data)
1816 		    : skb_transport_offset(skb)) + l4len;
1817 
1818 	/* find the field values */
1819 	cd_cmd = I40E_TX_CTX_DESC_TSO;
1820 	cd_tso_len = skb->len - *hdr_len;
1821 	cd_mss = skb_shinfo(skb)->gso_size;
1822 	*cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
1823 				((u64)cd_tso_len <<
1824 				 I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
1825 				((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
1826 	return 1;
1827 }
1828 
1829 /**
1830  * i40e_tsyn - set up the tsyn context descriptor
1831  * @tx_ring:  ptr to the ring to send
1832  * @skb:      ptr to the skb we're sending
1833  * @tx_flags: the collected send information
1834  *
1835  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
1836  **/
1837 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
1838 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
1839 {
1840 	struct i40e_pf *pf;
1841 
1842 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
1843 		return 0;
1844 
1845 	/* Tx timestamps cannot be sampled when doing TSO */
1846 	if (tx_flags & I40E_TX_FLAGS_TSO)
1847 		return 0;
1848 
1849 	/* only timestamp the outbound packet if the user has requested it and
1850 	 * we are not already transmitting a packet to be timestamped
1851 	 */
1852 	pf = i40e_netdev_to_pf(tx_ring->netdev);
1853 	if (pf->ptp_tx && !pf->ptp_tx_skb) {
1854 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
1855 		pf->ptp_tx_skb = skb_get(skb);
1856 	} else {
1857 		return 0;
1858 	}
1859 
1860 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
1861 				I40E_TXD_CTX_QW1_CMD_SHIFT;
1862 
1863 	return 1;
1864 }
1865 
1866 /**
1867  * i40e_tx_enable_csum - Enable Tx checksum offloads
1868  * @skb: send buffer
1869  * @tx_flags: Tx flags currently set
1870  * @td_cmd: Tx descriptor command bits to set
1871  * @td_offset: Tx descriptor header offsets to set
1872  * @cd_tunneling: ptr to context desc bits
1873  **/
1874 static void i40e_tx_enable_csum(struct sk_buff *skb, u32 tx_flags,
1875 				u32 *td_cmd, u32 *td_offset,
1876 				struct i40e_ring *tx_ring,
1877 				u32 *cd_tunneling)
1878 {
1879 	struct ipv6hdr *this_ipv6_hdr;
1880 	unsigned int this_tcp_hdrlen;
1881 	struct iphdr *this_ip_hdr;
1882 	u32 network_hdr_len;
1883 	u8 l4_hdr = 0;
1884 
1885 	if (skb->encapsulation) {
1886 		network_hdr_len = skb_inner_network_header_len(skb);
1887 		this_ip_hdr = inner_ip_hdr(skb);
1888 		this_ipv6_hdr = inner_ipv6_hdr(skb);
1889 		this_tcp_hdrlen = inner_tcp_hdrlen(skb);
1890 
1891 		if (tx_flags & I40E_TX_FLAGS_IPV4) {
1892 
1893 			if (tx_flags & I40E_TX_FLAGS_TSO) {
1894 				*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
1895 				ip_hdr(skb)->check = 0;
1896 			} else {
1897 				*cd_tunneling |=
1898 					 I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1899 			}
1900 		} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
1901 			if (tx_flags & I40E_TX_FLAGS_TSO) {
1902 				*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
1903 				ip_hdr(skb)->check = 0;
1904 			} else {
1905 				*cd_tunneling |=
1906 					 I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
1907 			}
1908 		}
1909 
1910 		/* Now set the ctx descriptor fields */
1911 		*cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
1912 					I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT |
1913 				   I40E_TXD_CTX_UDP_TUNNELING            |
1914 				   ((skb_inner_network_offset(skb) -
1915 					skb_transport_offset(skb)) >> 1) <<
1916 				   I40E_TXD_CTX_QW0_NATLEN_SHIFT;
1917 
1918 	} else {
1919 		network_hdr_len = skb_network_header_len(skb);
1920 		this_ip_hdr = ip_hdr(skb);
1921 		this_ipv6_hdr = ipv6_hdr(skb);
1922 		this_tcp_hdrlen = tcp_hdrlen(skb);
1923 	}
1924 
1925 	/* Enable IP checksum offloads */
1926 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
1927 		l4_hdr = this_ip_hdr->protocol;
1928 		/* the stack computes the IP header already, the only time we
1929 		 * need the hardware to recompute it is in the case of TSO.
1930 		 */
1931 		if (tx_flags & I40E_TX_FLAGS_TSO) {
1932 			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
1933 			this_ip_hdr->check = 0;
1934 		} else {
1935 			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
1936 		}
1937 		/* Now set the td_offset for IP header length */
1938 		*td_offset = (network_hdr_len >> 2) <<
1939 			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1940 	} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
1941 		l4_hdr = this_ipv6_hdr->nexthdr;
1942 		*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
1943 		/* Now set the td_offset for IP header length */
1944 		*td_offset = (network_hdr_len >> 2) <<
1945 			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
1946 	}
1947 	/* words in MACLEN + dwords in IPLEN + dwords in L4Len */
1948 	*td_offset |= (skb_network_offset(skb) >> 1) <<
1949 		       I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
1950 
1951 	/* Enable L4 checksum offloads */
1952 	switch (l4_hdr) {
1953 	case IPPROTO_TCP:
1954 		/* enable checksum offloads */
1955 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
1956 		*td_offset |= (this_tcp_hdrlen >> 2) <<
1957 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1958 		break;
1959 	case IPPROTO_SCTP:
1960 		/* enable SCTP checksum offload */
1961 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
1962 		*td_offset |= (sizeof(struct sctphdr) >> 2) <<
1963 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1964 		break;
1965 	case IPPROTO_UDP:
1966 		/* enable UDP checksum offload */
1967 		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
1968 		*td_offset |= (sizeof(struct udphdr) >> 2) <<
1969 			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
1970 		break;
1971 	default:
1972 		break;
1973 	}
1974 }
1975 
1976 /**
1977  * i40e_create_tx_ctx Build the Tx context descriptor
1978  * @tx_ring:  ring to create the descriptor on
1979  * @cd_type_cmd_tso_mss: Quad Word 1
1980  * @cd_tunneling: Quad Word 0 - bits 0-31
1981  * @cd_l2tag2: Quad Word 0 - bits 32-63
1982  **/
1983 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
1984 			       const u64 cd_type_cmd_tso_mss,
1985 			       const u32 cd_tunneling, const u32 cd_l2tag2)
1986 {
1987 	struct i40e_tx_context_desc *context_desc;
1988 	int i = tx_ring->next_to_use;
1989 
1990 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
1991 	    !cd_tunneling && !cd_l2tag2)
1992 		return;
1993 
1994 	/* grab the next descriptor */
1995 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
1996 
1997 	i++;
1998 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1999 
2000 	/* cpu_to_le32 and assign to struct fields */
2001 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2002 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2003 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2004 }
2005 
2006 /**
2007  * i40e_tx_map - Build the Tx descriptor
2008  * @tx_ring:  ring to send buffer on
2009  * @skb:      send buffer
2010  * @first:    first buffer info buffer to use
2011  * @tx_flags: collected send information
2012  * @hdr_len:  size of the packet header
2013  * @td_cmd:   the command field in the descriptor
2014  * @td_offset: offset for checksum or crc
2015  **/
2016 static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2017 			struct i40e_tx_buffer *first, u32 tx_flags,
2018 			const u8 hdr_len, u32 td_cmd, u32 td_offset)
2019 {
2020 	unsigned int data_len = skb->data_len;
2021 	unsigned int size = skb_headlen(skb);
2022 	struct skb_frag_struct *frag;
2023 	struct i40e_tx_buffer *tx_bi;
2024 	struct i40e_tx_desc *tx_desc;
2025 	u16 i = tx_ring->next_to_use;
2026 	u32 td_tag = 0;
2027 	dma_addr_t dma;
2028 	u16 gso_segs;
2029 
2030 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
2031 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
2032 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
2033 			 I40E_TX_FLAGS_VLAN_SHIFT;
2034 	}
2035 
2036 	if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
2037 		gso_segs = skb_shinfo(skb)->gso_segs;
2038 	else
2039 		gso_segs = 1;
2040 
2041 	/* multiply data chunks by size of headers */
2042 	first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
2043 	first->gso_segs = gso_segs;
2044 	first->skb = skb;
2045 	first->tx_flags = tx_flags;
2046 
2047 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
2048 
2049 	tx_desc = I40E_TX_DESC(tx_ring, i);
2050 	tx_bi = first;
2051 
2052 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
2053 		if (dma_mapping_error(tx_ring->dev, dma))
2054 			goto dma_error;
2055 
2056 		/* record length, and DMA address */
2057 		dma_unmap_len_set(tx_bi, len, size);
2058 		dma_unmap_addr_set(tx_bi, dma, dma);
2059 
2060 		tx_desc->buffer_addr = cpu_to_le64(dma);
2061 
2062 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
2063 			tx_desc->cmd_type_offset_bsz =
2064 				build_ctob(td_cmd, td_offset,
2065 					   I40E_MAX_DATA_PER_TXD, td_tag);
2066 
2067 			tx_desc++;
2068 			i++;
2069 			if (i == tx_ring->count) {
2070 				tx_desc = I40E_TX_DESC(tx_ring, 0);
2071 				i = 0;
2072 			}
2073 
2074 			dma += I40E_MAX_DATA_PER_TXD;
2075 			size -= I40E_MAX_DATA_PER_TXD;
2076 
2077 			tx_desc->buffer_addr = cpu_to_le64(dma);
2078 		}
2079 
2080 		if (likely(!data_len))
2081 			break;
2082 
2083 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
2084 							  size, td_tag);
2085 
2086 		tx_desc++;
2087 		i++;
2088 		if (i == tx_ring->count) {
2089 			tx_desc = I40E_TX_DESC(tx_ring, 0);
2090 			i = 0;
2091 		}
2092 
2093 		size = skb_frag_size(frag);
2094 		data_len -= size;
2095 
2096 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
2097 				       DMA_TO_DEVICE);
2098 
2099 		tx_bi = &tx_ring->tx_bi[i];
2100 	}
2101 
2102 	/* Place RS bit on last descriptor of any packet that spans across the
2103 	 * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
2104 	 */
2105 #define WB_STRIDE 0x3
2106 	if (((i & WB_STRIDE) != WB_STRIDE) &&
2107 	    (first <= &tx_ring->tx_bi[i]) &&
2108 	    (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
2109 		tx_desc->cmd_type_offset_bsz =
2110 			build_ctob(td_cmd, td_offset, size, td_tag) |
2111 			cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
2112 					 I40E_TXD_QW1_CMD_SHIFT);
2113 	} else {
2114 		tx_desc->cmd_type_offset_bsz =
2115 			build_ctob(td_cmd, td_offset, size, td_tag) |
2116 			cpu_to_le64((u64)I40E_TXD_CMD <<
2117 					 I40E_TXD_QW1_CMD_SHIFT);
2118 	}
2119 
2120 	netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
2121 						 tx_ring->queue_index),
2122 			     first->bytecount);
2123 
2124 	/* set the timestamp */
2125 	first->time_stamp = jiffies;
2126 
2127 	/* Force memory writes to complete before letting h/w
2128 	 * know there are new descriptors to fetch.  (Only
2129 	 * applicable for weak-ordered memory model archs,
2130 	 * such as IA-64).
2131 	 */
2132 	wmb();
2133 
2134 	/* set next_to_watch value indicating a packet is present */
2135 	first->next_to_watch = tx_desc;
2136 
2137 	i++;
2138 	if (i == tx_ring->count)
2139 		i = 0;
2140 
2141 	tx_ring->next_to_use = i;
2142 
2143 	/* notify HW of packet */
2144 	writel(i, tx_ring->tail);
2145 
2146 	return;
2147 
2148 dma_error:
2149 	dev_info(tx_ring->dev, "TX DMA map failed\n");
2150 
2151 	/* clear dma mappings for failed tx_bi map */
2152 	for (;;) {
2153 		tx_bi = &tx_ring->tx_bi[i];
2154 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
2155 		if (tx_bi == first)
2156 			break;
2157 		if (i == 0)
2158 			i = tx_ring->count;
2159 		i--;
2160 	}
2161 
2162 	tx_ring->next_to_use = i;
2163 }
2164 
2165 /**
2166  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2167  * @tx_ring: the ring to be checked
2168  * @size:    the size buffer we want to assure is available
2169  *
2170  * Returns -EBUSY if a stop is needed, else 0
2171  **/
2172 static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2173 {
2174 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2175 	/* Memory barrier before checking head and tail */
2176 	smp_mb();
2177 
2178 	/* Check again in a case another CPU has just made room available. */
2179 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2180 		return -EBUSY;
2181 
2182 	/* A reprieve! - use start_queue because it doesn't call schedule */
2183 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
2184 	++tx_ring->tx_stats.restart_queue;
2185 	return 0;
2186 }
2187 
2188 /**
2189  * i40e_maybe_stop_tx - 1st level check for tx stop conditions
2190  * @tx_ring: the ring to be checked
2191  * @size:    the size buffer we want to assure is available
2192  *
2193  * Returns 0 if stop is not needed
2194  **/
2195 static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2196 {
2197 	if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
2198 		return 0;
2199 	return __i40e_maybe_stop_tx(tx_ring, size);
2200 }
2201 
2202 /**
2203  * i40e_xmit_descriptor_count - calculate number of tx descriptors needed
2204  * @skb:     send buffer
2205  * @tx_ring: ring to send buffer on
2206  *
2207  * Returns number of data descriptors needed for this skb. Returns 0 to indicate
2208  * there is not enough descriptors available in this ring since we need at least
2209  * one descriptor.
2210  **/
2211 static int i40e_xmit_descriptor_count(struct sk_buff *skb,
2212 				      struct i40e_ring *tx_ring)
2213 {
2214 	unsigned int f;
2215 	int count = 0;
2216 
2217 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
2218 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
2219 	 *       + 4 desc gap to avoid the cache line where head is,
2220 	 *       + 1 desc for context descriptor,
2221 	 * otherwise try next time
2222 	 */
2223 	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
2224 		count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
2225 
2226 	count += TXD_USE_COUNT(skb_headlen(skb));
2227 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
2228 		tx_ring->tx_stats.tx_busy++;
2229 		return 0;
2230 	}
2231 	return count;
2232 }
2233 
2234 /**
2235  * i40e_xmit_frame_ring - Sends buffer on Tx ring
2236  * @skb:     send buffer
2237  * @tx_ring: ring to send buffer on
2238  *
2239  * Returns NETDEV_TX_OK if sent, else an error code
2240  **/
2241 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
2242 					struct i40e_ring *tx_ring)
2243 {
2244 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
2245 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
2246 	struct i40e_tx_buffer *first;
2247 	u32 td_offset = 0;
2248 	u32 tx_flags = 0;
2249 	__be16 protocol;
2250 	u32 td_cmd = 0;
2251 	u8 hdr_len = 0;
2252 	int tsyn;
2253 	int tso;
2254 	if (0 == i40e_xmit_descriptor_count(skb, tx_ring))
2255 		return NETDEV_TX_BUSY;
2256 
2257 	/* prepare the xmit flags */
2258 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
2259 		goto out_drop;
2260 
2261 	/* obtain protocol of skb */
2262 	protocol = skb->protocol;
2263 
2264 	/* record the location of the first descriptor for this packet */
2265 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
2266 
2267 	/* setup IPv4/IPv6 offloads */
2268 	if (protocol == htons(ETH_P_IP))
2269 		tx_flags |= I40E_TX_FLAGS_IPV4;
2270 	else if (protocol == htons(ETH_P_IPV6))
2271 		tx_flags |= I40E_TX_FLAGS_IPV6;
2272 
2273 	tso = i40e_tso(tx_ring, skb, tx_flags, protocol, &hdr_len,
2274 		       &cd_type_cmd_tso_mss, &cd_tunneling);
2275 
2276 	if (tso < 0)
2277 		goto out_drop;
2278 	else if (tso)
2279 		tx_flags |= I40E_TX_FLAGS_TSO;
2280 
2281 	skb_tx_timestamp(skb);
2282 
2283 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
2284 
2285 	if (tsyn)
2286 		tx_flags |= I40E_TX_FLAGS_TSYN;
2287 
2288 	/* always enable CRC insertion offload */
2289 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
2290 
2291 	/* Always offload the checksum, since it's in the data descriptor */
2292 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
2293 		tx_flags |= I40E_TX_FLAGS_CSUM;
2294 
2295 		i40e_tx_enable_csum(skb, tx_flags, &td_cmd, &td_offset,
2296 				    tx_ring, &cd_tunneling);
2297 	}
2298 
2299 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
2300 			   cd_tunneling, cd_l2tag2);
2301 
2302 	/* Add Flow Director ATR if it's enabled.
2303 	 *
2304 	 * NOTE: this must always be directly before the data descriptor.
2305 	 */
2306 	i40e_atr(tx_ring, skb, tx_flags, protocol);
2307 
2308 	i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
2309 		    td_cmd, td_offset);
2310 
2311 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
2312 
2313 	return NETDEV_TX_OK;
2314 
2315 out_drop:
2316 	dev_kfree_skb_any(skb);
2317 	return NETDEV_TX_OK;
2318 }
2319 
2320 /**
2321  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
2322  * @skb:    send buffer
2323  * @netdev: network interface device structure
2324  *
2325  * Returns NETDEV_TX_OK if sent, else an error code
2326  **/
2327 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
2328 {
2329 	struct i40e_netdev_priv *np = netdev_priv(netdev);
2330 	struct i40e_vsi *vsi = np->vsi;
2331 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
2332 
2333 	/* hardware can't handle really short frames, hardware padding works
2334 	 * beyond this point
2335 	 */
2336 	if (unlikely(skb->len < I40E_MIN_TX_LEN)) {
2337 		if (skb_pad(skb, I40E_MIN_TX_LEN - skb->len))
2338 			return NETDEV_TX_OK;
2339 		skb->len = I40E_MIN_TX_LEN;
2340 		skb_set_tail_pointer(skb, I40E_MIN_TX_LEN);
2341 	}
2342 
2343 	return i40e_xmit_frame_ring(skb, tx_ring);
2344 }
2345