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1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 - 2016 Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program.  If not, see <http://www.gnu.org/licenses/>.
17  *
18  * The full GNU General Public License is included in this distribution in
19  * the file called "COPYING".
20  *
21  * Contact Information:
22  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  ******************************************************************************/
26 
27 #include <linux/prefetch.h>
28 #include <net/busy_poll.h>
29 #include <linux/bpf_trace.h>
30 #include "i40e.h"
31 #include "i40e_trace.h"
32 #include "i40e_prototype.h"
33 
build_ctob(u32 td_cmd,u32 td_offset,unsigned int size,u32 td_tag)34 static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
35 				u32 td_tag)
36 {
37 	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
38 			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
39 			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
40 			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
41 			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
42 }
43 
44 #define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
45 /**
46  * i40e_fdir - Generate a Flow Director descriptor based on fdata
47  * @tx_ring: Tx ring to send buffer on
48  * @fdata: Flow director filter data
49  * @add: Indicate if we are adding a rule or deleting one
50  *
51  **/
i40e_fdir(struct i40e_ring * tx_ring,struct i40e_fdir_filter * fdata,bool add)52 static void i40e_fdir(struct i40e_ring *tx_ring,
53 		      struct i40e_fdir_filter *fdata, bool add)
54 {
55 	struct i40e_filter_program_desc *fdir_desc;
56 	struct i40e_pf *pf = tx_ring->vsi->back;
57 	u32 flex_ptype, dtype_cmd;
58 	u16 i;
59 
60 	/* grab the next descriptor */
61 	i = tx_ring->next_to_use;
62 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
63 
64 	i++;
65 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
66 
67 	flex_ptype = I40E_TXD_FLTR_QW0_QINDEX_MASK &
68 		     (fdata->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT);
69 
70 	flex_ptype |= I40E_TXD_FLTR_QW0_FLEXOFF_MASK &
71 		      (fdata->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
72 
73 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
74 		      (fdata->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
75 
76 	flex_ptype |= I40E_TXD_FLTR_QW0_PCTYPE_MASK &
77 		      (fdata->flex_offset << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT);
78 
79 	/* Use LAN VSI Id if not programmed by user */
80 	flex_ptype |= I40E_TXD_FLTR_QW0_DEST_VSI_MASK &
81 		      ((u32)(fdata->dest_vsi ? : pf->vsi[pf->lan_vsi]->id) <<
82 		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT);
83 
84 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
85 
86 	dtype_cmd |= add ?
87 		     I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
88 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT :
89 		     I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
90 		     I40E_TXD_FLTR_QW1_PCMD_SHIFT;
91 
92 	dtype_cmd |= I40E_TXD_FLTR_QW1_DEST_MASK &
93 		     (fdata->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT);
94 
95 	dtype_cmd |= I40E_TXD_FLTR_QW1_FD_STATUS_MASK &
96 		     (fdata->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT);
97 
98 	if (fdata->cnt_index) {
99 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
100 		dtype_cmd |= I40E_TXD_FLTR_QW1_CNTINDEX_MASK &
101 			     ((u32)fdata->cnt_index <<
102 			      I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT);
103 	}
104 
105 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
106 	fdir_desc->rsvd = cpu_to_le32(0);
107 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
108 	fdir_desc->fd_id = cpu_to_le32(fdata->fd_id);
109 }
110 
111 #define I40E_FD_CLEAN_DELAY 10
112 /**
113  * i40e_program_fdir_filter - Program a Flow Director filter
114  * @fdir_data: Packet data that will be filter parameters
115  * @raw_packet: the pre-allocated packet buffer for FDir
116  * @pf: The PF pointer
117  * @add: True for add/update, False for remove
118  **/
i40e_program_fdir_filter(struct i40e_fdir_filter * fdir_data,u8 * raw_packet,struct i40e_pf * pf,bool add)119 static int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data,
120 				    u8 *raw_packet, struct i40e_pf *pf,
121 				    bool add)
122 {
123 	struct i40e_tx_buffer *tx_buf, *first;
124 	struct i40e_tx_desc *tx_desc;
125 	struct i40e_ring *tx_ring;
126 	struct i40e_vsi *vsi;
127 	struct device *dev;
128 	dma_addr_t dma;
129 	u32 td_cmd = 0;
130 	u16 i;
131 
132 	/* find existing FDIR VSI */
133 	vsi = i40e_find_vsi_by_type(pf, I40E_VSI_FDIR);
134 	if (!vsi)
135 		return -ENOENT;
136 
137 	tx_ring = vsi->tx_rings[0];
138 	dev = tx_ring->dev;
139 
140 	/* we need two descriptors to add/del a filter and we can wait */
141 	for (i = I40E_FD_CLEAN_DELAY; I40E_DESC_UNUSED(tx_ring) < 2; i--) {
142 		if (!i)
143 			return -EAGAIN;
144 		msleep_interruptible(1);
145 	}
146 
147 	dma = dma_map_single(dev, raw_packet,
148 			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
149 	if (dma_mapping_error(dev, dma))
150 		goto dma_fail;
151 
152 	/* grab the next descriptor */
153 	i = tx_ring->next_to_use;
154 	first = &tx_ring->tx_bi[i];
155 	i40e_fdir(tx_ring, fdir_data, add);
156 
157 	/* Now program a dummy descriptor */
158 	i = tx_ring->next_to_use;
159 	tx_desc = I40E_TX_DESC(tx_ring, i);
160 	tx_buf = &tx_ring->tx_bi[i];
161 
162 	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
163 
164 	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
165 
166 	/* record length, and DMA address */
167 	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
168 	dma_unmap_addr_set(tx_buf, dma, dma);
169 
170 	tx_desc->buffer_addr = cpu_to_le64(dma);
171 	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
172 
173 	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
174 	tx_buf->raw_buf = (void *)raw_packet;
175 
176 	tx_desc->cmd_type_offset_bsz =
177 		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
178 
179 	/* Force memory writes to complete before letting h/w
180 	 * know there are new descriptors to fetch.
181 	 */
182 	wmb();
183 
184 	/* Mark the data descriptor to be watched */
185 	first->next_to_watch = tx_desc;
186 
187 	writel(tx_ring->next_to_use, tx_ring->tail);
188 	return 0;
189 
190 dma_fail:
191 	return -1;
192 }
193 
194 #define IP_HEADER_OFFSET 14
195 #define I40E_UDPIP_DUMMY_PACKET_LEN 42
196 /**
197  * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
198  * @vsi: pointer to the targeted VSI
199  * @fd_data: the flow director data required for the FDir descriptor
200  * @add: true adds a filter, false removes it
201  *
202  * Returns 0 if the filters were successfully added or removed
203  **/
i40e_add_del_fdir_udpv4(struct i40e_vsi * vsi,struct i40e_fdir_filter * fd_data,bool add)204 static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
205 				   struct i40e_fdir_filter *fd_data,
206 				   bool add)
207 {
208 	struct i40e_pf *pf = vsi->back;
209 	struct udphdr *udp;
210 	struct iphdr *ip;
211 	u8 *raw_packet;
212 	int ret;
213 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
214 		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
215 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
216 
217 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
218 	if (!raw_packet)
219 		return -ENOMEM;
220 	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
221 
222 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
223 	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
224 	      + sizeof(struct iphdr));
225 
226 	ip->daddr = fd_data->dst_ip;
227 	udp->dest = fd_data->dst_port;
228 	ip->saddr = fd_data->src_ip;
229 	udp->source = fd_data->src_port;
230 
231 	if (fd_data->flex_filter) {
232 		u8 *payload = raw_packet + I40E_UDPIP_DUMMY_PACKET_LEN;
233 		__be16 pattern = fd_data->flex_word;
234 		u16 off = fd_data->flex_offset;
235 
236 		*((__force __be16 *)(payload + off)) = pattern;
237 	}
238 
239 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
240 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
241 	if (ret) {
242 		dev_info(&pf->pdev->dev,
243 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
244 			 fd_data->pctype, fd_data->fd_id, ret);
245 		/* Free the packet buffer since it wasn't added to the ring */
246 		kfree(raw_packet);
247 		return -EOPNOTSUPP;
248 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
249 		if (add)
250 			dev_info(&pf->pdev->dev,
251 				 "Filter OK for PCTYPE %d loc = %d\n",
252 				 fd_data->pctype, fd_data->fd_id);
253 		else
254 			dev_info(&pf->pdev->dev,
255 				 "Filter deleted for PCTYPE %d loc = %d\n",
256 				 fd_data->pctype, fd_data->fd_id);
257 	}
258 
259 	if (add)
260 		pf->fd_udp4_filter_cnt++;
261 	else
262 		pf->fd_udp4_filter_cnt--;
263 
264 	return 0;
265 }
266 
267 #define I40E_TCPIP_DUMMY_PACKET_LEN 54
268 /**
269  * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
270  * @vsi: pointer to the targeted VSI
271  * @fd_data: the flow director data required for the FDir descriptor
272  * @add: true adds a filter, false removes it
273  *
274  * Returns 0 if the filters were successfully added or removed
275  **/
i40e_add_del_fdir_tcpv4(struct i40e_vsi * vsi,struct i40e_fdir_filter * fd_data,bool add)276 static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
277 				   struct i40e_fdir_filter *fd_data,
278 				   bool add)
279 {
280 	struct i40e_pf *pf = vsi->back;
281 	struct tcphdr *tcp;
282 	struct iphdr *ip;
283 	u8 *raw_packet;
284 	int ret;
285 	/* Dummy packet */
286 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
287 		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
288 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
289 		0x0, 0x72, 0, 0, 0, 0};
290 
291 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
292 	if (!raw_packet)
293 		return -ENOMEM;
294 	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
295 
296 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
297 	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
298 	      + sizeof(struct iphdr));
299 
300 	ip->daddr = fd_data->dst_ip;
301 	tcp->dest = fd_data->dst_port;
302 	ip->saddr = fd_data->src_ip;
303 	tcp->source = fd_data->src_port;
304 
305 	if (fd_data->flex_filter) {
306 		u8 *payload = raw_packet + I40E_TCPIP_DUMMY_PACKET_LEN;
307 		__be16 pattern = fd_data->flex_word;
308 		u16 off = fd_data->flex_offset;
309 
310 		*((__force __be16 *)(payload + off)) = pattern;
311 	}
312 
313 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
314 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
315 	if (ret) {
316 		dev_info(&pf->pdev->dev,
317 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
318 			 fd_data->pctype, fd_data->fd_id, ret);
319 		/* Free the packet buffer since it wasn't added to the ring */
320 		kfree(raw_packet);
321 		return -EOPNOTSUPP;
322 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
323 		if (add)
324 			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
325 				 fd_data->pctype, fd_data->fd_id);
326 		else
327 			dev_info(&pf->pdev->dev,
328 				 "Filter deleted for PCTYPE %d loc = %d\n",
329 				 fd_data->pctype, fd_data->fd_id);
330 	}
331 
332 	if (add) {
333 		pf->fd_tcp4_filter_cnt++;
334 		if ((pf->flags & I40E_FLAG_FD_ATR_ENABLED) &&
335 		    I40E_DEBUG_FD & pf->hw.debug_mask)
336 			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
337 		pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
338 	} else {
339 		pf->fd_tcp4_filter_cnt--;
340 	}
341 
342 	return 0;
343 }
344 
345 #define I40E_SCTPIP_DUMMY_PACKET_LEN 46
346 /**
347  * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
348  * a specific flow spec
349  * @vsi: pointer to the targeted VSI
350  * @fd_data: the flow director data required for the FDir descriptor
351  * @add: true adds a filter, false removes it
352  *
353  * Returns 0 if the filters were successfully added or removed
354  **/
i40e_add_del_fdir_sctpv4(struct i40e_vsi * vsi,struct i40e_fdir_filter * fd_data,bool add)355 static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
356 				    struct i40e_fdir_filter *fd_data,
357 				    bool add)
358 {
359 	struct i40e_pf *pf = vsi->back;
360 	struct sctphdr *sctp;
361 	struct iphdr *ip;
362 	u8 *raw_packet;
363 	int ret;
364 	/* Dummy packet */
365 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
366 		0x45, 0, 0, 0x20, 0, 0, 0x40, 0, 0x40, 0x84, 0, 0, 0, 0, 0, 0,
367 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
368 
369 	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
370 	if (!raw_packet)
371 		return -ENOMEM;
372 	memcpy(raw_packet, packet, I40E_SCTPIP_DUMMY_PACKET_LEN);
373 
374 	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
375 	sctp = (struct sctphdr *)(raw_packet + IP_HEADER_OFFSET
376 	      + sizeof(struct iphdr));
377 
378 	ip->daddr = fd_data->dst_ip;
379 	sctp->dest = fd_data->dst_port;
380 	ip->saddr = fd_data->src_ip;
381 	sctp->source = fd_data->src_port;
382 
383 	if (fd_data->flex_filter) {
384 		u8 *payload = raw_packet + I40E_SCTPIP_DUMMY_PACKET_LEN;
385 		__be16 pattern = fd_data->flex_word;
386 		u16 off = fd_data->flex_offset;
387 
388 		*((__force __be16 *)(payload + off)) = pattern;
389 	}
390 
391 	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_SCTP;
392 	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
393 	if (ret) {
394 		dev_info(&pf->pdev->dev,
395 			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
396 			 fd_data->pctype, fd_data->fd_id, ret);
397 		/* Free the packet buffer since it wasn't added to the ring */
398 		kfree(raw_packet);
399 		return -EOPNOTSUPP;
400 	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
401 		if (add)
402 			dev_info(&pf->pdev->dev,
403 				 "Filter OK for PCTYPE %d loc = %d\n",
404 				 fd_data->pctype, fd_data->fd_id);
405 		else
406 			dev_info(&pf->pdev->dev,
407 				 "Filter deleted for PCTYPE %d loc = %d\n",
408 				 fd_data->pctype, fd_data->fd_id);
409 	}
410 
411 	if (add)
412 		pf->fd_sctp4_filter_cnt++;
413 	else
414 		pf->fd_sctp4_filter_cnt--;
415 
416 	return 0;
417 }
418 
419 #define I40E_IP_DUMMY_PACKET_LEN 34
420 /**
421  * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
422  * a specific flow spec
423  * @vsi: pointer to the targeted VSI
424  * @fd_data: the flow director data required for the FDir descriptor
425  * @add: true adds a filter, false removes it
426  *
427  * Returns 0 if the filters were successfully added or removed
428  **/
i40e_add_del_fdir_ipv4(struct i40e_vsi * vsi,struct i40e_fdir_filter * fd_data,bool add)429 static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
430 				  struct i40e_fdir_filter *fd_data,
431 				  bool add)
432 {
433 	struct i40e_pf *pf = vsi->back;
434 	struct iphdr *ip;
435 	u8 *raw_packet;
436 	int ret;
437 	int i;
438 	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
439 		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
440 		0, 0, 0, 0};
441 
442 	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
443 	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
444 		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
445 		if (!raw_packet)
446 			return -ENOMEM;
447 		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
448 		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
449 
450 		ip->saddr = fd_data->src_ip;
451 		ip->daddr = fd_data->dst_ip;
452 		ip->protocol = 0;
453 
454 		if (fd_data->flex_filter) {
455 			u8 *payload = raw_packet + I40E_IP_DUMMY_PACKET_LEN;
456 			__be16 pattern = fd_data->flex_word;
457 			u16 off = fd_data->flex_offset;
458 
459 			*((__force __be16 *)(payload + off)) = pattern;
460 		}
461 
462 		fd_data->pctype = i;
463 		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
464 		if (ret) {
465 			dev_info(&pf->pdev->dev,
466 				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
467 				 fd_data->pctype, fd_data->fd_id, ret);
468 			/* The packet buffer wasn't added to the ring so we
469 			 * need to free it now.
470 			 */
471 			kfree(raw_packet);
472 			return -EOPNOTSUPP;
473 		} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
474 			if (add)
475 				dev_info(&pf->pdev->dev,
476 					 "Filter OK for PCTYPE %d loc = %d\n",
477 					 fd_data->pctype, fd_data->fd_id);
478 			else
479 				dev_info(&pf->pdev->dev,
480 					 "Filter deleted for PCTYPE %d loc = %d\n",
481 					 fd_data->pctype, fd_data->fd_id);
482 		}
483 	}
484 
485 	if (add)
486 		pf->fd_ip4_filter_cnt++;
487 	else
488 		pf->fd_ip4_filter_cnt--;
489 
490 	return 0;
491 }
492 
493 /**
494  * i40e_add_del_fdir - Build raw packets to add/del fdir filter
495  * @vsi: pointer to the targeted VSI
496  * @cmd: command to get or set RX flow classification rules
497  * @add: true adds a filter, false removes it
498  *
499  **/
i40e_add_del_fdir(struct i40e_vsi * vsi,struct i40e_fdir_filter * input,bool add)500 int i40e_add_del_fdir(struct i40e_vsi *vsi,
501 		      struct i40e_fdir_filter *input, bool add)
502 {
503 	struct i40e_pf *pf = vsi->back;
504 	int ret;
505 
506 	switch (input->flow_type & ~FLOW_EXT) {
507 	case TCP_V4_FLOW:
508 		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
509 		break;
510 	case UDP_V4_FLOW:
511 		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
512 		break;
513 	case SCTP_V4_FLOW:
514 		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
515 		break;
516 	case IP_USER_FLOW:
517 		switch (input->ip4_proto) {
518 		case IPPROTO_TCP:
519 			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
520 			break;
521 		case IPPROTO_UDP:
522 			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
523 			break;
524 		case IPPROTO_SCTP:
525 			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
526 			break;
527 		case IPPROTO_IP:
528 			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
529 			break;
530 		default:
531 			/* We cannot support masking based on protocol */
532 			dev_info(&pf->pdev->dev, "Unsupported IPv4 protocol 0x%02x\n",
533 				 input->ip4_proto);
534 			return -EINVAL;
535 		}
536 		break;
537 	default:
538 		dev_info(&pf->pdev->dev, "Unsupported flow type 0x%02x\n",
539 			 input->flow_type);
540 		return -EINVAL;
541 	}
542 
543 	/* The buffer allocated here will be normally be freed by
544 	 * i40e_clean_fdir_tx_irq() as it reclaims resources after transmit
545 	 * completion. In the event of an error adding the buffer to the FDIR
546 	 * ring, it will immediately be freed. It may also be freed by
547 	 * i40e_clean_tx_ring() when closing the VSI.
548 	 */
549 	return ret;
550 }
551 
552 /**
553  * i40e_fd_handle_status - check the Programming Status for FD
554  * @rx_ring: the Rx ring for this descriptor
555  * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
556  * @prog_id: the id originally used for programming
557  *
558  * This is used to verify if the FD programming or invalidation
559  * requested by SW to the HW is successful or not and take actions accordingly.
560  **/
i40e_fd_handle_status(struct i40e_ring * rx_ring,union i40e_rx_desc * rx_desc,u8 prog_id)561 static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
562 				  union i40e_rx_desc *rx_desc, u8 prog_id)
563 {
564 	struct i40e_pf *pf = rx_ring->vsi->back;
565 	struct pci_dev *pdev = pf->pdev;
566 	u32 fcnt_prog, fcnt_avail;
567 	u32 error;
568 	u64 qw;
569 
570 	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
571 	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
572 		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
573 
574 	if (error == BIT(I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
575 		pf->fd_inv = le32_to_cpu(rx_desc->wb.qword0.hi_dword.fd_id);
576 		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
577 		    (I40E_DEBUG_FD & pf->hw.debug_mask))
578 			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
579 				 pf->fd_inv);
580 
581 		/* Check if the programming error is for ATR.
582 		 * If so, auto disable ATR and set a state for
583 		 * flush in progress. Next time we come here if flush is in
584 		 * progress do nothing, once flush is complete the state will
585 		 * be cleared.
586 		 */
587 		if (test_bit(__I40E_FD_FLUSH_REQUESTED, pf->state))
588 			return;
589 
590 		pf->fd_add_err++;
591 		/* store the current atr filter count */
592 		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
593 
594 		if ((rx_desc->wb.qword0.hi_dword.fd_id == 0) &&
595 		    pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED) {
596 			pf->flags |= I40E_FLAG_FD_ATR_AUTO_DISABLED;
597 			set_bit(__I40E_FD_FLUSH_REQUESTED, pf->state);
598 		}
599 
600 		/* filter programming failed most likely due to table full */
601 		fcnt_prog = i40e_get_global_fd_count(pf);
602 		fcnt_avail = pf->fdir_pf_filter_count;
603 		/* If ATR is running fcnt_prog can quickly change,
604 		 * if we are very close to full, it makes sense to disable
605 		 * FD ATR/SB and then re-enable it when there is room.
606 		 */
607 		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
608 			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
609 			    !(pf->flags & I40E_FLAG_FD_SB_AUTO_DISABLED)) {
610 				pf->flags |= I40E_FLAG_FD_SB_AUTO_DISABLED;
611 				if (I40E_DEBUG_FD & pf->hw.debug_mask)
612 					dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
613 			}
614 		}
615 	} else if (error == BIT(I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
616 		if (I40E_DEBUG_FD & pf->hw.debug_mask)
617 			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
618 				 rx_desc->wb.qword0.hi_dword.fd_id);
619 	}
620 }
621 
622 /**
623  * i40e_unmap_and_free_tx_resource - Release a Tx buffer
624  * @ring:      the ring that owns the buffer
625  * @tx_buffer: the buffer to free
626  **/
i40e_unmap_and_free_tx_resource(struct i40e_ring * ring,struct i40e_tx_buffer * tx_buffer)627 static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
628 					    struct i40e_tx_buffer *tx_buffer)
629 {
630 	if (tx_buffer->skb) {
631 		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
632 			kfree(tx_buffer->raw_buf);
633 		else if (ring_is_xdp(ring))
634 			page_frag_free(tx_buffer->raw_buf);
635 		else
636 			dev_kfree_skb_any(tx_buffer->skb);
637 		if (dma_unmap_len(tx_buffer, len))
638 			dma_unmap_single(ring->dev,
639 					 dma_unmap_addr(tx_buffer, dma),
640 					 dma_unmap_len(tx_buffer, len),
641 					 DMA_TO_DEVICE);
642 	} else if (dma_unmap_len(tx_buffer, len)) {
643 		dma_unmap_page(ring->dev,
644 			       dma_unmap_addr(tx_buffer, dma),
645 			       dma_unmap_len(tx_buffer, len),
646 			       DMA_TO_DEVICE);
647 	}
648 
649 	tx_buffer->next_to_watch = NULL;
650 	tx_buffer->skb = NULL;
651 	dma_unmap_len_set(tx_buffer, len, 0);
652 	/* tx_buffer must be completely set up in the transmit path */
653 }
654 
655 /**
656  * i40e_clean_tx_ring - Free any empty Tx buffers
657  * @tx_ring: ring to be cleaned
658  **/
i40e_clean_tx_ring(struct i40e_ring * tx_ring)659 void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
660 {
661 	unsigned long bi_size;
662 	u16 i;
663 
664 	/* ring already cleared, nothing to do */
665 	if (!tx_ring->tx_bi)
666 		return;
667 
668 	/* Free all the Tx ring sk_buffs */
669 	for (i = 0; i < tx_ring->count; i++)
670 		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
671 
672 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
673 	memset(tx_ring->tx_bi, 0, bi_size);
674 
675 	/* Zero out the descriptor ring */
676 	memset(tx_ring->desc, 0, tx_ring->size);
677 
678 	tx_ring->next_to_use = 0;
679 	tx_ring->next_to_clean = 0;
680 
681 	if (!tx_ring->netdev)
682 		return;
683 
684 	/* cleanup Tx queue statistics */
685 	netdev_tx_reset_queue(txring_txq(tx_ring));
686 }
687 
688 /**
689  * i40e_free_tx_resources - Free Tx resources per queue
690  * @tx_ring: Tx descriptor ring for a specific queue
691  *
692  * Free all transmit software resources
693  **/
i40e_free_tx_resources(struct i40e_ring * tx_ring)694 void i40e_free_tx_resources(struct i40e_ring *tx_ring)
695 {
696 	i40e_clean_tx_ring(tx_ring);
697 	kfree(tx_ring->tx_bi);
698 	tx_ring->tx_bi = NULL;
699 
700 	if (tx_ring->desc) {
701 		dma_free_coherent(tx_ring->dev, tx_ring->size,
702 				  tx_ring->desc, tx_ring->dma);
703 		tx_ring->desc = NULL;
704 	}
705 }
706 
707 /**
708  * i40e_get_tx_pending - how many tx descriptors not processed
709  * @tx_ring: the ring of descriptors
710  *
711  * Since there is no access to the ring head register
712  * in XL710, we need to use our local copies
713  **/
i40e_get_tx_pending(struct i40e_ring * ring)714 u32 i40e_get_tx_pending(struct i40e_ring *ring)
715 {
716 	u32 head, tail;
717 
718 	head = i40e_get_head(ring);
719 	tail = readl(ring->tail);
720 
721 	if (head != tail)
722 		return (head < tail) ?
723 			tail - head : (tail + ring->count - head);
724 
725 	return 0;
726 }
727 
728 #define WB_STRIDE 4
729 
730 /**
731  * i40e_clean_tx_irq - Reclaim resources after transmit completes
732  * @vsi: the VSI we care about
733  * @tx_ring: Tx ring to clean
734  * @napi_budget: Used to determine if we are in netpoll
735  *
736  * Returns true if there's any budget left (e.g. the clean is finished)
737  **/
i40e_clean_tx_irq(struct i40e_vsi * vsi,struct i40e_ring * tx_ring,int napi_budget)738 static bool i40e_clean_tx_irq(struct i40e_vsi *vsi,
739 			      struct i40e_ring *tx_ring, int napi_budget)
740 {
741 	u16 i = tx_ring->next_to_clean;
742 	struct i40e_tx_buffer *tx_buf;
743 	struct i40e_tx_desc *tx_head;
744 	struct i40e_tx_desc *tx_desc;
745 	unsigned int total_bytes = 0, total_packets = 0;
746 	unsigned int budget = vsi->work_limit;
747 
748 	tx_buf = &tx_ring->tx_bi[i];
749 	tx_desc = I40E_TX_DESC(tx_ring, i);
750 	i -= tx_ring->count;
751 
752 	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
753 
754 	do {
755 		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
756 
757 		/* if next_to_watch is not set then there is no work pending */
758 		if (!eop_desc)
759 			break;
760 
761 		/* prevent any other reads prior to eop_desc */
762 		smp_rmb();
763 
764 		i40e_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
765 		/* we have caught up to head, no work left to do */
766 		if (tx_head == tx_desc)
767 			break;
768 
769 		/* clear next_to_watch to prevent false hangs */
770 		tx_buf->next_to_watch = NULL;
771 
772 		/* update the statistics for this packet */
773 		total_bytes += tx_buf->bytecount;
774 		total_packets += tx_buf->gso_segs;
775 
776 		/* free the skb/XDP data */
777 		if (ring_is_xdp(tx_ring))
778 			page_frag_free(tx_buf->raw_buf);
779 		else
780 			napi_consume_skb(tx_buf->skb, napi_budget);
781 
782 		/* unmap skb header data */
783 		dma_unmap_single(tx_ring->dev,
784 				 dma_unmap_addr(tx_buf, dma),
785 				 dma_unmap_len(tx_buf, len),
786 				 DMA_TO_DEVICE);
787 
788 		/* clear tx_buffer data */
789 		tx_buf->skb = NULL;
790 		dma_unmap_len_set(tx_buf, len, 0);
791 
792 		/* unmap remaining buffers */
793 		while (tx_desc != eop_desc) {
794 			i40e_trace(clean_tx_irq_unmap,
795 				   tx_ring, tx_desc, tx_buf);
796 
797 			tx_buf++;
798 			tx_desc++;
799 			i++;
800 			if (unlikely(!i)) {
801 				i -= tx_ring->count;
802 				tx_buf = tx_ring->tx_bi;
803 				tx_desc = I40E_TX_DESC(tx_ring, 0);
804 			}
805 
806 			/* unmap any remaining paged data */
807 			if (dma_unmap_len(tx_buf, len)) {
808 				dma_unmap_page(tx_ring->dev,
809 					       dma_unmap_addr(tx_buf, dma),
810 					       dma_unmap_len(tx_buf, len),
811 					       DMA_TO_DEVICE);
812 				dma_unmap_len_set(tx_buf, len, 0);
813 			}
814 		}
815 
816 		/* move us one more past the eop_desc for start of next pkt */
817 		tx_buf++;
818 		tx_desc++;
819 		i++;
820 		if (unlikely(!i)) {
821 			i -= tx_ring->count;
822 			tx_buf = tx_ring->tx_bi;
823 			tx_desc = I40E_TX_DESC(tx_ring, 0);
824 		}
825 
826 		prefetch(tx_desc);
827 
828 		/* update budget accounting */
829 		budget--;
830 	} while (likely(budget));
831 
832 	i += tx_ring->count;
833 	tx_ring->next_to_clean = i;
834 	u64_stats_update_begin(&tx_ring->syncp);
835 	tx_ring->stats.bytes += total_bytes;
836 	tx_ring->stats.packets += total_packets;
837 	u64_stats_update_end(&tx_ring->syncp);
838 	tx_ring->q_vector->tx.total_bytes += total_bytes;
839 	tx_ring->q_vector->tx.total_packets += total_packets;
840 
841 	if (tx_ring->flags & I40E_TXR_FLAGS_WB_ON_ITR) {
842 		/* check to see if there are < 4 descriptors
843 		 * waiting to be written back, then kick the hardware to force
844 		 * them to be written back in case we stay in NAPI.
845 		 * In this mode on X722 we do not enable Interrupt.
846 		 */
847 		unsigned int j = i40e_get_tx_pending(tx_ring);
848 
849 		if (budget &&
850 		    ((j / WB_STRIDE) == 0) && (j > 0) &&
851 		    !test_bit(__I40E_VSI_DOWN, vsi->state) &&
852 		    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
853 			tx_ring->arm_wb = true;
854 	}
855 
856 	if (ring_is_xdp(tx_ring))
857 		return !!budget;
858 
859 	/* notify netdev of completed buffers */
860 	netdev_tx_completed_queue(txring_txq(tx_ring),
861 				  total_packets, total_bytes);
862 
863 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
864 	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
865 		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
866 		/* Make sure that anybody stopping the queue after this
867 		 * sees the new next_to_clean.
868 		 */
869 		smp_mb();
870 		if (__netif_subqueue_stopped(tx_ring->netdev,
871 					     tx_ring->queue_index) &&
872 		   !test_bit(__I40E_VSI_DOWN, vsi->state)) {
873 			netif_wake_subqueue(tx_ring->netdev,
874 					    tx_ring->queue_index);
875 			++tx_ring->tx_stats.restart_queue;
876 		}
877 	}
878 
879 	return !!budget;
880 }
881 
882 /**
883  * i40e_enable_wb_on_itr - Arm hardware to do a wb, interrupts are not enabled
884  * @vsi: the VSI we care about
885  * @q_vector: the vector on which to enable writeback
886  *
887  **/
i40e_enable_wb_on_itr(struct i40e_vsi * vsi,struct i40e_q_vector * q_vector)888 static void i40e_enable_wb_on_itr(struct i40e_vsi *vsi,
889 				  struct i40e_q_vector *q_vector)
890 {
891 	u16 flags = q_vector->tx.ring[0].flags;
892 	u32 val;
893 
894 	if (!(flags & I40E_TXR_FLAGS_WB_ON_ITR))
895 		return;
896 
897 	if (q_vector->arm_wb_state)
898 		return;
899 
900 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
901 		val = I40E_PFINT_DYN_CTLN_WB_ON_ITR_MASK |
902 		      I40E_PFINT_DYN_CTLN_ITR_INDX_MASK; /* set noitr */
903 
904 		wr32(&vsi->back->hw,
905 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx + vsi->base_vector - 1),
906 		     val);
907 	} else {
908 		val = I40E_PFINT_DYN_CTL0_WB_ON_ITR_MASK |
909 		      I40E_PFINT_DYN_CTL0_ITR_INDX_MASK; /* set noitr */
910 
911 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
912 	}
913 	q_vector->arm_wb_state = true;
914 }
915 
916 /**
917  * i40e_force_wb - Issue SW Interrupt so HW does a wb
918  * @vsi: the VSI we care about
919  * @q_vector: the vector  on which to force writeback
920  *
921  **/
i40e_force_wb(struct i40e_vsi * vsi,struct i40e_q_vector * q_vector)922 void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
923 {
924 	if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
925 		u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
926 			  I40E_PFINT_DYN_CTLN_ITR_INDX_MASK | /* set noitr */
927 			  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
928 			  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
929 			  /* allow 00 to be written to the index */
930 
931 		wr32(&vsi->back->hw,
932 		     I40E_PFINT_DYN_CTLN(q_vector->v_idx +
933 					 vsi->base_vector - 1), val);
934 	} else {
935 		u32 val = I40E_PFINT_DYN_CTL0_INTENA_MASK |
936 			  I40E_PFINT_DYN_CTL0_ITR_INDX_MASK | /* set noitr */
937 			  I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK |
938 			  I40E_PFINT_DYN_CTL0_SW_ITR_INDX_ENA_MASK;
939 			/* allow 00 to be written to the index */
940 
941 		wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0, val);
942 	}
943 }
944 
945 /**
946  * i40e_set_new_dynamic_itr - Find new ITR level
947  * @rc: structure containing ring performance data
948  *
949  * Returns true if ITR changed, false if not
950  *
951  * Stores a new ITR value based on packets and byte counts during
952  * the last interrupt.  The advantage of per interrupt computation
953  * is faster updates and more accurate ITR for the current traffic
954  * pattern.  Constants in this function were computed based on
955  * theoretical maximum wire speed and thresholds were set based on
956  * testing data as well as attempting to minimize response time
957  * while increasing bulk throughput.
958  **/
i40e_set_new_dynamic_itr(struct i40e_ring_container * rc)959 static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
960 {
961 	enum i40e_latency_range new_latency_range = rc->latency_range;
962 	u32 new_itr = rc->itr;
963 	int bytes_per_int;
964 	unsigned int usecs, estimated_usecs;
965 
966 	if (rc->total_packets == 0 || !rc->itr)
967 		return false;
968 
969 	usecs = (rc->itr << 1) * ITR_COUNTDOWN_START;
970 	bytes_per_int = rc->total_bytes / usecs;
971 
972 	/* The calculations in this algorithm depend on interrupts actually
973 	 * firing at the ITR rate. This may not happen if the packet rate is
974 	 * really low, or if we've been napi polling. Check to make sure
975 	 * that's not the case before we continue.
976 	 */
977 	estimated_usecs = jiffies_to_usecs(jiffies - rc->last_itr_update);
978 	if (estimated_usecs > usecs) {
979 		new_latency_range = I40E_LOW_LATENCY;
980 		goto reset_latency;
981 	}
982 
983 	/* simple throttlerate management
984 	 *   0-10MB/s   lowest (50000 ints/s)
985 	 *  10-20MB/s   low    (20000 ints/s)
986 	 *  20-1249MB/s bulk   (18000 ints/s)
987 	 *
988 	 * The math works out because the divisor is in 10^(-6) which
989 	 * turns the bytes/us input value into MB/s values, but
990 	 * make sure to use usecs, as the register values written
991 	 * are in 2 usec increments in the ITR registers, and make sure
992 	 * to use the smoothed values that the countdown timer gives us.
993 	 */
994 	switch (new_latency_range) {
995 	case I40E_LOWEST_LATENCY:
996 		if (bytes_per_int > 10)
997 			new_latency_range = I40E_LOW_LATENCY;
998 		break;
999 	case I40E_LOW_LATENCY:
1000 		if (bytes_per_int > 20)
1001 			new_latency_range = I40E_BULK_LATENCY;
1002 		else if (bytes_per_int <= 10)
1003 			new_latency_range = I40E_LOWEST_LATENCY;
1004 		break;
1005 	case I40E_BULK_LATENCY:
1006 	default:
1007 		if (bytes_per_int <= 20)
1008 			new_latency_range = I40E_LOW_LATENCY;
1009 		break;
1010 	}
1011 
1012 reset_latency:
1013 	rc->latency_range = new_latency_range;
1014 
1015 	switch (new_latency_range) {
1016 	case I40E_LOWEST_LATENCY:
1017 		new_itr = I40E_ITR_50K;
1018 		break;
1019 	case I40E_LOW_LATENCY:
1020 		new_itr = I40E_ITR_20K;
1021 		break;
1022 	case I40E_BULK_LATENCY:
1023 		new_itr = I40E_ITR_18K;
1024 		break;
1025 	default:
1026 		break;
1027 	}
1028 
1029 	rc->total_bytes = 0;
1030 	rc->total_packets = 0;
1031 	rc->last_itr_update = jiffies;
1032 
1033 	if (new_itr != rc->itr) {
1034 		rc->itr = new_itr;
1035 		return true;
1036 	}
1037 	return false;
1038 }
1039 
1040 /**
1041  * i40e_reuse_rx_page - page flip buffer and store it back on the ring
1042  * @rx_ring: rx descriptor ring to store buffers on
1043  * @old_buff: donor buffer to have page reused
1044  *
1045  * Synchronizes page for reuse by the adapter
1046  **/
i40e_reuse_rx_page(struct i40e_ring * rx_ring,struct i40e_rx_buffer * old_buff)1047 static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
1048 			       struct i40e_rx_buffer *old_buff)
1049 {
1050 	struct i40e_rx_buffer *new_buff;
1051 	u16 nta = rx_ring->next_to_alloc;
1052 
1053 	new_buff = &rx_ring->rx_bi[nta];
1054 
1055 	/* update, and store next to alloc */
1056 	nta++;
1057 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
1058 
1059 	/* transfer page from old buffer to new buffer */
1060 	new_buff->dma		= old_buff->dma;
1061 	new_buff->page		= old_buff->page;
1062 	new_buff->page_offset	= old_buff->page_offset;
1063 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
1064 }
1065 
1066 /**
1067  * i40e_rx_is_programming_status - check for programming status descriptor
1068  * @qw: qword representing status_error_len in CPU ordering
1069  *
1070  * The value of in the descriptor length field indicate if this
1071  * is a programming status descriptor for flow director or FCoE
1072  * by the value of I40E_RX_PROG_STATUS_DESC_LENGTH, otherwise
1073  * it is a packet descriptor.
1074  **/
i40e_rx_is_programming_status(u64 qw)1075 static inline bool i40e_rx_is_programming_status(u64 qw)
1076 {
1077 	/* The Rx filter programming status and SPH bit occupy the same
1078 	 * spot in the descriptor. Since we don't support packet split we
1079 	 * can just reuse the bit as an indication that this is a
1080 	 * programming status descriptor.
1081 	 */
1082 	return qw & I40E_RXD_QW1_LENGTH_SPH_MASK;
1083 }
1084 
1085 /**
1086  * i40e_clean_programming_status - clean the programming status descriptor
1087  * @rx_ring: the rx ring that has this descriptor
1088  * @rx_desc: the rx descriptor written back by HW
1089  * @qw: qword representing status_error_len in CPU ordering
1090  *
1091  * Flow director should handle FD_FILTER_STATUS to check its filter programming
1092  * status being successful or not and take actions accordingly. FCoE should
1093  * handle its context/filter programming/invalidation status and take actions.
1094  *
1095  **/
i40e_clean_programming_status(struct i40e_ring * rx_ring,union i40e_rx_desc * rx_desc,u64 qw)1096 static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
1097 					  union i40e_rx_desc *rx_desc,
1098 					  u64 qw)
1099 {
1100 	struct i40e_rx_buffer *rx_buffer;
1101 	u32 ntc = rx_ring->next_to_clean;
1102 	u8 id;
1103 
1104 	/* fetch, update, and store next to clean */
1105 	rx_buffer = &rx_ring->rx_bi[ntc++];
1106 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1107 	rx_ring->next_to_clean = ntc;
1108 
1109 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1110 
1111 	/* place unused page back on the ring */
1112 	i40e_reuse_rx_page(rx_ring, rx_buffer);
1113 	rx_ring->rx_stats.page_reuse_count++;
1114 
1115 	/* clear contents of buffer_info */
1116 	rx_buffer->page = NULL;
1117 
1118 	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
1119 		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
1120 
1121 	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
1122 		i40e_fd_handle_status(rx_ring, rx_desc, id);
1123 }
1124 
1125 /**
1126  * i40e_setup_tx_descriptors - Allocate the Tx descriptors
1127  * @tx_ring: the tx ring to set up
1128  *
1129  * Return 0 on success, negative on error
1130  **/
i40e_setup_tx_descriptors(struct i40e_ring * tx_ring)1131 int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
1132 {
1133 	struct device *dev = tx_ring->dev;
1134 	int bi_size;
1135 
1136 	if (!dev)
1137 		return -ENOMEM;
1138 
1139 	/* warn if we are about to overwrite the pointer */
1140 	WARN_ON(tx_ring->tx_bi);
1141 	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
1142 	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
1143 	if (!tx_ring->tx_bi)
1144 		goto err;
1145 
1146 	u64_stats_init(&tx_ring->syncp);
1147 
1148 	/* round up to nearest 4K */
1149 	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
1150 	/* add u32 for head writeback, align after this takes care of
1151 	 * guaranteeing this is at least one cache line in size
1152 	 */
1153 	tx_ring->size += sizeof(u32);
1154 	tx_ring->size = ALIGN(tx_ring->size, 4096);
1155 	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
1156 					   &tx_ring->dma, GFP_KERNEL);
1157 	if (!tx_ring->desc) {
1158 		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
1159 			 tx_ring->size);
1160 		goto err;
1161 	}
1162 
1163 	tx_ring->next_to_use = 0;
1164 	tx_ring->next_to_clean = 0;
1165 	return 0;
1166 
1167 err:
1168 	kfree(tx_ring->tx_bi);
1169 	tx_ring->tx_bi = NULL;
1170 	return -ENOMEM;
1171 }
1172 
1173 /**
1174  * i40e_clean_rx_ring - Free Rx buffers
1175  * @rx_ring: ring to be cleaned
1176  **/
i40e_clean_rx_ring(struct i40e_ring * rx_ring)1177 void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1178 {
1179 	unsigned long bi_size;
1180 	u16 i;
1181 
1182 	/* ring already cleared, nothing to do */
1183 	if (!rx_ring->rx_bi)
1184 		return;
1185 
1186 	if (rx_ring->skb) {
1187 		dev_kfree_skb(rx_ring->skb);
1188 		rx_ring->skb = NULL;
1189 	}
1190 
1191 	/* Free all the Rx ring sk_buffs */
1192 	for (i = 0; i < rx_ring->count; i++) {
1193 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
1194 
1195 		if (!rx_bi->page)
1196 			continue;
1197 
1198 		/* Invalidate cache lines that may have been written to by
1199 		 * device so that we avoid corrupting memory.
1200 		 */
1201 		dma_sync_single_range_for_cpu(rx_ring->dev,
1202 					      rx_bi->dma,
1203 					      rx_bi->page_offset,
1204 					      rx_ring->rx_buf_len,
1205 					      DMA_FROM_DEVICE);
1206 
1207 		/* free resources associated with mapping */
1208 		dma_unmap_page_attrs(rx_ring->dev, rx_bi->dma,
1209 				     i40e_rx_pg_size(rx_ring),
1210 				     DMA_FROM_DEVICE,
1211 				     I40E_RX_DMA_ATTR);
1212 
1213 		__page_frag_cache_drain(rx_bi->page, rx_bi->pagecnt_bias);
1214 
1215 		rx_bi->page = NULL;
1216 		rx_bi->page_offset = 0;
1217 	}
1218 
1219 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1220 	memset(rx_ring->rx_bi, 0, bi_size);
1221 
1222 	/* Zero out the descriptor ring */
1223 	memset(rx_ring->desc, 0, rx_ring->size);
1224 
1225 	rx_ring->next_to_alloc = 0;
1226 	rx_ring->next_to_clean = 0;
1227 	rx_ring->next_to_use = 0;
1228 }
1229 
1230 /**
1231  * i40e_free_rx_resources - Free Rx resources
1232  * @rx_ring: ring to clean the resources from
1233  *
1234  * Free all receive software resources
1235  **/
i40e_free_rx_resources(struct i40e_ring * rx_ring)1236 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1237 {
1238 	i40e_clean_rx_ring(rx_ring);
1239 	rx_ring->xdp_prog = NULL;
1240 	kfree(rx_ring->rx_bi);
1241 	rx_ring->rx_bi = NULL;
1242 
1243 	if (rx_ring->desc) {
1244 		dma_free_coherent(rx_ring->dev, rx_ring->size,
1245 				  rx_ring->desc, rx_ring->dma);
1246 		rx_ring->desc = NULL;
1247 	}
1248 }
1249 
1250 /**
1251  * i40e_setup_rx_descriptors - Allocate Rx descriptors
1252  * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1253  *
1254  * Returns 0 on success, negative on failure
1255  **/
i40e_setup_rx_descriptors(struct i40e_ring * rx_ring)1256 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1257 {
1258 	struct device *dev = rx_ring->dev;
1259 	int bi_size;
1260 
1261 	/* warn if we are about to overwrite the pointer */
1262 	WARN_ON(rx_ring->rx_bi);
1263 	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1264 	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1265 	if (!rx_ring->rx_bi)
1266 		goto err;
1267 
1268 	u64_stats_init(&rx_ring->syncp);
1269 
1270 	/* Round up to nearest 4K */
1271 	rx_ring->size = rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1272 	rx_ring->size = ALIGN(rx_ring->size, 4096);
1273 	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1274 					   &rx_ring->dma, GFP_KERNEL);
1275 
1276 	if (!rx_ring->desc) {
1277 		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1278 			 rx_ring->size);
1279 		goto err;
1280 	}
1281 
1282 	rx_ring->next_to_alloc = 0;
1283 	rx_ring->next_to_clean = 0;
1284 	rx_ring->next_to_use = 0;
1285 
1286 	rx_ring->xdp_prog = rx_ring->vsi->xdp_prog;
1287 
1288 	return 0;
1289 err:
1290 	kfree(rx_ring->rx_bi);
1291 	rx_ring->rx_bi = NULL;
1292 	return -ENOMEM;
1293 }
1294 
1295 /**
1296  * i40e_release_rx_desc - Store the new tail and head values
1297  * @rx_ring: ring to bump
1298  * @val: new head index
1299  **/
i40e_release_rx_desc(struct i40e_ring * rx_ring,u32 val)1300 static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1301 {
1302 	rx_ring->next_to_use = val;
1303 
1304 	/* update next to alloc since we have filled the ring */
1305 	rx_ring->next_to_alloc = val;
1306 
1307 	/* Force memory writes to complete before letting h/w
1308 	 * know there are new descriptors to fetch.  (Only
1309 	 * applicable for weak-ordered memory model archs,
1310 	 * such as IA-64).
1311 	 */
1312 	wmb();
1313 	writel(val, rx_ring->tail);
1314 }
1315 
1316 /**
1317  * i40e_rx_offset - Return expected offset into page to access data
1318  * @rx_ring: Ring we are requesting offset of
1319  *
1320  * Returns the offset value for ring into the data buffer.
1321  */
i40e_rx_offset(struct i40e_ring * rx_ring)1322 static inline unsigned int i40e_rx_offset(struct i40e_ring *rx_ring)
1323 {
1324 	return ring_uses_build_skb(rx_ring) ? I40E_SKB_PAD : 0;
1325 }
1326 
1327 /**
1328  * i40e_alloc_mapped_page - recycle or make a new page
1329  * @rx_ring: ring to use
1330  * @bi: rx_buffer struct to modify
1331  *
1332  * Returns true if the page was successfully allocated or
1333  * reused.
1334  **/
i40e_alloc_mapped_page(struct i40e_ring * rx_ring,struct i40e_rx_buffer * bi)1335 static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
1336 				   struct i40e_rx_buffer *bi)
1337 {
1338 	struct page *page = bi->page;
1339 	dma_addr_t dma;
1340 
1341 	/* since we are recycling buffers we should seldom need to alloc */
1342 	if (likely(page)) {
1343 		rx_ring->rx_stats.page_reuse_count++;
1344 		return true;
1345 	}
1346 
1347 	/* alloc new page for storage */
1348 	page = dev_alloc_pages(i40e_rx_pg_order(rx_ring));
1349 	if (unlikely(!page)) {
1350 		rx_ring->rx_stats.alloc_page_failed++;
1351 		return false;
1352 	}
1353 
1354 	/* map page for use */
1355 	dma = dma_map_page_attrs(rx_ring->dev, page, 0,
1356 				 i40e_rx_pg_size(rx_ring),
1357 				 DMA_FROM_DEVICE,
1358 				 I40E_RX_DMA_ATTR);
1359 
1360 	/* if mapping failed free memory back to system since
1361 	 * there isn't much point in holding memory we can't use
1362 	 */
1363 	if (dma_mapping_error(rx_ring->dev, dma)) {
1364 		__free_pages(page, i40e_rx_pg_order(rx_ring));
1365 		rx_ring->rx_stats.alloc_page_failed++;
1366 		return false;
1367 	}
1368 
1369 	bi->dma = dma;
1370 	bi->page = page;
1371 	bi->page_offset = i40e_rx_offset(rx_ring);
1372 
1373 	/* initialize pagecnt_bias to 1 representing we fully own page */
1374 	bi->pagecnt_bias = 1;
1375 
1376 	return true;
1377 }
1378 
1379 /**
1380  * i40e_receive_skb - Send a completed packet up the stack
1381  * @rx_ring:  rx ring in play
1382  * @skb: packet to send up
1383  * @vlan_tag: vlan tag for packet
1384  **/
i40e_receive_skb(struct i40e_ring * rx_ring,struct sk_buff * skb,u16 vlan_tag)1385 static void i40e_receive_skb(struct i40e_ring *rx_ring,
1386 			     struct sk_buff *skb, u16 vlan_tag)
1387 {
1388 	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1389 
1390 	if ((rx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
1391 	    (vlan_tag & VLAN_VID_MASK))
1392 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1393 
1394 	napi_gro_receive(&q_vector->napi, skb);
1395 }
1396 
1397 /**
1398  * i40e_alloc_rx_buffers - Replace used receive buffers
1399  * @rx_ring: ring to place buffers on
1400  * @cleaned_count: number of buffers to replace
1401  *
1402  * Returns false if all allocations were successful, true if any fail
1403  **/
i40e_alloc_rx_buffers(struct i40e_ring * rx_ring,u16 cleaned_count)1404 bool i40e_alloc_rx_buffers(struct i40e_ring *rx_ring, u16 cleaned_count)
1405 {
1406 	u16 ntu = rx_ring->next_to_use;
1407 	union i40e_rx_desc *rx_desc;
1408 	struct i40e_rx_buffer *bi;
1409 
1410 	/* do nothing if no valid netdev defined */
1411 	if (!rx_ring->netdev || !cleaned_count)
1412 		return false;
1413 
1414 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
1415 	bi = &rx_ring->rx_bi[ntu];
1416 
1417 	do {
1418 		if (!i40e_alloc_mapped_page(rx_ring, bi))
1419 			goto no_buffers;
1420 
1421 		/* sync the buffer for use by the device */
1422 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
1423 						 bi->page_offset,
1424 						 rx_ring->rx_buf_len,
1425 						 DMA_FROM_DEVICE);
1426 
1427 		/* Refresh the desc even if buffer_addrs didn't change
1428 		 * because each write-back erases this info.
1429 		 */
1430 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
1431 
1432 		rx_desc++;
1433 		bi++;
1434 		ntu++;
1435 		if (unlikely(ntu == rx_ring->count)) {
1436 			rx_desc = I40E_RX_DESC(rx_ring, 0);
1437 			bi = rx_ring->rx_bi;
1438 			ntu = 0;
1439 		}
1440 
1441 		/* clear the status bits for the next_to_use descriptor */
1442 		rx_desc->wb.qword1.status_error_len = 0;
1443 
1444 		cleaned_count--;
1445 	} while (cleaned_count);
1446 
1447 	if (rx_ring->next_to_use != ntu)
1448 		i40e_release_rx_desc(rx_ring, ntu);
1449 
1450 	return false;
1451 
1452 no_buffers:
1453 	if (rx_ring->next_to_use != ntu)
1454 		i40e_release_rx_desc(rx_ring, ntu);
1455 
1456 	/* make sure to come back via polling to try again after
1457 	 * allocation failure
1458 	 */
1459 	return true;
1460 }
1461 
1462 /**
1463  * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1464  * @vsi: the VSI we care about
1465  * @skb: skb currently being received and modified
1466  * @rx_desc: the receive descriptor
1467  **/
i40e_rx_checksum(struct i40e_vsi * vsi,struct sk_buff * skb,union i40e_rx_desc * rx_desc)1468 static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1469 				    struct sk_buff *skb,
1470 				    union i40e_rx_desc *rx_desc)
1471 {
1472 	struct i40e_rx_ptype_decoded decoded;
1473 	u32 rx_error, rx_status;
1474 	bool ipv4, ipv6;
1475 	u8 ptype;
1476 	u64 qword;
1477 
1478 	qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1479 	ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >> I40E_RXD_QW1_PTYPE_SHIFT;
1480 	rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1481 		   I40E_RXD_QW1_ERROR_SHIFT;
1482 	rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1483 		    I40E_RXD_QW1_STATUS_SHIFT;
1484 	decoded = decode_rx_desc_ptype(ptype);
1485 
1486 	skb->ip_summed = CHECKSUM_NONE;
1487 
1488 	skb_checksum_none_assert(skb);
1489 
1490 	/* Rx csum enabled and ip headers found? */
1491 	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1492 		return;
1493 
1494 	/* did the hardware decode the packet and checksum? */
1495 	if (!(rx_status & BIT(I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1496 		return;
1497 
1498 	/* both known and outer_ip must be set for the below code to work */
1499 	if (!(decoded.known && decoded.outer_ip))
1500 		return;
1501 
1502 	ipv4 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1503 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4);
1504 	ipv6 = (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP) &&
1505 	       (decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6);
1506 
1507 	if (ipv4 &&
1508 	    (rx_error & (BIT(I40E_RX_DESC_ERROR_IPE_SHIFT) |
1509 			 BIT(I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1510 		goto checksum_fail;
1511 
1512 	/* likely incorrect csum if alternate IP extension headers found */
1513 	if (ipv6 &&
1514 	    rx_status & BIT(I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1515 		/* don't increment checksum err here, non-fatal err */
1516 		return;
1517 
1518 	/* there was some L4 error, count error and punt packet to the stack */
1519 	if (rx_error & BIT(I40E_RX_DESC_ERROR_L4E_SHIFT))
1520 		goto checksum_fail;
1521 
1522 	/* handle packets that were not able to be checksummed due
1523 	 * to arrival speed, in this case the stack can compute
1524 	 * the csum.
1525 	 */
1526 	if (rx_error & BIT(I40E_RX_DESC_ERROR_PPRS_SHIFT))
1527 		return;
1528 
1529 	/* If there is an outer header present that might contain a checksum
1530 	 * we need to bump the checksum level by 1 to reflect the fact that
1531 	 * we are indicating we validated the inner checksum.
1532 	 */
1533 	if (decoded.tunnel_type >= I40E_RX_PTYPE_TUNNEL_IP_GRENAT)
1534 		skb->csum_level = 1;
1535 
1536 	/* Only report checksum unnecessary for TCP, UDP, or SCTP */
1537 	switch (decoded.inner_prot) {
1538 	case I40E_RX_PTYPE_INNER_PROT_TCP:
1539 	case I40E_RX_PTYPE_INNER_PROT_UDP:
1540 	case I40E_RX_PTYPE_INNER_PROT_SCTP:
1541 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1542 		/* fall though */
1543 	default:
1544 		break;
1545 	}
1546 
1547 	return;
1548 
1549 checksum_fail:
1550 	vsi->back->hw_csum_rx_error++;
1551 }
1552 
1553 /**
1554  * i40e_ptype_to_htype - get a hash type
1555  * @ptype: the ptype value from the descriptor
1556  *
1557  * Returns a hash type to be used by skb_set_hash
1558  **/
i40e_ptype_to_htype(u8 ptype)1559 static inline int i40e_ptype_to_htype(u8 ptype)
1560 {
1561 	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1562 
1563 	if (!decoded.known)
1564 		return PKT_HASH_TYPE_NONE;
1565 
1566 	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1567 	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1568 		return PKT_HASH_TYPE_L4;
1569 	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1570 		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1571 		return PKT_HASH_TYPE_L3;
1572 	else
1573 		return PKT_HASH_TYPE_L2;
1574 }
1575 
1576 /**
1577  * i40e_rx_hash - set the hash value in the skb
1578  * @ring: descriptor ring
1579  * @rx_desc: specific descriptor
1580  **/
i40e_rx_hash(struct i40e_ring * ring,union i40e_rx_desc * rx_desc,struct sk_buff * skb,u8 rx_ptype)1581 static inline void i40e_rx_hash(struct i40e_ring *ring,
1582 				union i40e_rx_desc *rx_desc,
1583 				struct sk_buff *skb,
1584 				u8 rx_ptype)
1585 {
1586 	u32 hash;
1587 	const __le64 rss_mask =
1588 		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1589 			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1590 
1591 	if (!(ring->netdev->features & NETIF_F_RXHASH))
1592 		return;
1593 
1594 	if ((rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask) {
1595 		hash = le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1596 		skb_set_hash(skb, hash, i40e_ptype_to_htype(rx_ptype));
1597 	}
1598 }
1599 
1600 /**
1601  * i40e_process_skb_fields - Populate skb header fields from Rx descriptor
1602  * @rx_ring: rx descriptor ring packet is being transacted on
1603  * @rx_desc: pointer to the EOP Rx descriptor
1604  * @skb: pointer to current skb being populated
1605  * @rx_ptype: the packet type decoded by hardware
1606  *
1607  * This function checks the ring, descriptor, and packet information in
1608  * order to populate the hash, checksum, VLAN, protocol, and
1609  * other fields within the skb.
1610  **/
1611 static inline
i40e_process_skb_fields(struct i40e_ring * rx_ring,union i40e_rx_desc * rx_desc,struct sk_buff * skb,u8 rx_ptype)1612 void i40e_process_skb_fields(struct i40e_ring *rx_ring,
1613 			     union i40e_rx_desc *rx_desc, struct sk_buff *skb,
1614 			     u8 rx_ptype)
1615 {
1616 	u64 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1617 	u32 rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1618 			I40E_RXD_QW1_STATUS_SHIFT;
1619 	u32 tsynvalid = rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK;
1620 	u32 tsyn = (rx_status & I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1621 		   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT;
1622 
1623 	if (unlikely(tsynvalid))
1624 		i40e_ptp_rx_hwtstamp(rx_ring->vsi->back, skb, tsyn);
1625 
1626 	i40e_rx_hash(rx_ring, rx_desc, skb, rx_ptype);
1627 
1628 	i40e_rx_checksum(rx_ring->vsi, skb, rx_desc);
1629 
1630 	skb_record_rx_queue(skb, rx_ring->queue_index);
1631 
1632 	/* modifies the skb - consumes the enet header */
1633 	skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1634 }
1635 
1636 /**
1637  * i40e_cleanup_headers - Correct empty headers
1638  * @rx_ring: rx descriptor ring packet is being transacted on
1639  * @skb: pointer to current skb being fixed
1640  * @rx_desc: pointer to the EOP Rx descriptor
1641  *
1642  * Also address the case where we are pulling data in on pages only
1643  * and as such no data is present in the skb header.
1644  *
1645  * In addition if skb is not at least 60 bytes we need to pad it so that
1646  * it is large enough to qualify as a valid Ethernet frame.
1647  *
1648  * Returns true if an error was encountered and skb was freed.
1649  **/
i40e_cleanup_headers(struct i40e_ring * rx_ring,struct sk_buff * skb,union i40e_rx_desc * rx_desc)1650 static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
1651 				 union i40e_rx_desc *rx_desc)
1652 
1653 {
1654 	/* XDP packets use error pointer so abort at this point */
1655 	if (IS_ERR(skb))
1656 		return true;
1657 
1658 	/* ERR_MASK will only have valid bits if EOP set, and
1659 	 * what we are doing here is actually checking
1660 	 * I40E_RX_DESC_ERROR_RXE_SHIFT, since it is the zeroth bit in
1661 	 * the error field
1662 	 */
1663 	if (unlikely(i40e_test_staterr(rx_desc,
1664 				       BIT(I40E_RXD_QW1_ERROR_SHIFT)))) {
1665 		dev_kfree_skb_any(skb);
1666 		return true;
1667 	}
1668 
1669 	/* if eth_skb_pad returns an error the skb was freed */
1670 	if (eth_skb_pad(skb))
1671 		return true;
1672 
1673 	return false;
1674 }
1675 
1676 /**
1677  * i40e_page_is_reusable - check if any reuse is possible
1678  * @page: page struct to check
1679  *
1680  * A page is not reusable if it was allocated under low memory
1681  * conditions, or it's not in the same NUMA node as this CPU.
1682  */
i40e_page_is_reusable(struct page * page)1683 static inline bool i40e_page_is_reusable(struct page *page)
1684 {
1685 	return (page_to_nid(page) == numa_mem_id()) &&
1686 		!page_is_pfmemalloc(page);
1687 }
1688 
1689 /**
1690  * i40e_can_reuse_rx_page - Determine if this page can be reused by
1691  * the adapter for another receive
1692  *
1693  * @rx_buffer: buffer containing the page
1694  *
1695  * If page is reusable, rx_buffer->page_offset is adjusted to point to
1696  * an unused region in the page.
1697  *
1698  * For small pages, @truesize will be a constant value, half the size
1699  * of the memory at page.  We'll attempt to alternate between high and
1700  * low halves of the page, with one half ready for use by the hardware
1701  * and the other half being consumed by the stack.  We use the page
1702  * ref count to determine whether the stack has finished consuming the
1703  * portion of this page that was passed up with a previous packet.  If
1704  * the page ref count is >1, we'll assume the "other" half page is
1705  * still busy, and this page cannot be reused.
1706  *
1707  * For larger pages, @truesize will be the actual space used by the
1708  * received packet (adjusted upward to an even multiple of the cache
1709  * line size).  This will advance through the page by the amount
1710  * actually consumed by the received packets while there is still
1711  * space for a buffer.  Each region of larger pages will be used at
1712  * most once, after which the page will not be reused.
1713  *
1714  * In either case, if the page is reusable its refcount is increased.
1715  **/
i40e_can_reuse_rx_page(struct i40e_rx_buffer * rx_buffer)1716 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer)
1717 {
1718 	unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
1719 	struct page *page = rx_buffer->page;
1720 
1721 	/* Is any reuse possible? */
1722 	if (unlikely(!i40e_page_is_reusable(page)))
1723 		return false;
1724 
1725 #if (PAGE_SIZE < 8192)
1726 	/* if we are only owner of page we can reuse it */
1727 	if (unlikely((page_count(page) - pagecnt_bias) > 1))
1728 		return false;
1729 #else
1730 #define I40E_LAST_OFFSET \
1731 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - I40E_RXBUFFER_2048)
1732 	if (rx_buffer->page_offset > I40E_LAST_OFFSET)
1733 		return false;
1734 #endif
1735 
1736 	/* If we have drained the page fragment pool we need to update
1737 	 * the pagecnt_bias and page count so that we fully restock the
1738 	 * number of references the driver holds.
1739 	 */
1740 	if (unlikely(!pagecnt_bias)) {
1741 		page_ref_add(page, USHRT_MAX);
1742 		rx_buffer->pagecnt_bias = USHRT_MAX;
1743 	}
1744 
1745 	return true;
1746 }
1747 
1748 /**
1749  * i40e_add_rx_frag - Add contents of Rx buffer to sk_buff
1750  * @rx_ring: rx descriptor ring to transact packets on
1751  * @rx_buffer: buffer containing page to add
1752  * @skb: sk_buff to place the data into
1753  * @size: packet length from rx_desc
1754  *
1755  * This function will add the data contained in rx_buffer->page to the skb.
1756  * It will just attach the page as a frag to the skb.
1757  *
1758  * The function will then update the page offset.
1759  **/
i40e_add_rx_frag(struct i40e_ring * rx_ring,struct i40e_rx_buffer * rx_buffer,struct sk_buff * skb,unsigned int size)1760 static void i40e_add_rx_frag(struct i40e_ring *rx_ring,
1761 			     struct i40e_rx_buffer *rx_buffer,
1762 			     struct sk_buff *skb,
1763 			     unsigned int size)
1764 {
1765 #if (PAGE_SIZE < 8192)
1766 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1767 #else
1768 	unsigned int truesize = SKB_DATA_ALIGN(size + i40e_rx_offset(rx_ring));
1769 #endif
1770 
1771 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
1772 			rx_buffer->page_offset, size, truesize);
1773 
1774 	/* page is being used so we must update the page offset */
1775 #if (PAGE_SIZE < 8192)
1776 	rx_buffer->page_offset ^= truesize;
1777 #else
1778 	rx_buffer->page_offset += truesize;
1779 #endif
1780 }
1781 
1782 /**
1783  * i40e_get_rx_buffer - Fetch Rx buffer and synchronize data for use
1784  * @rx_ring: rx descriptor ring to transact packets on
1785  * @size: size of buffer to add to skb
1786  *
1787  * This function will pull an Rx buffer from the ring and synchronize it
1788  * for use by the CPU.
1789  */
i40e_get_rx_buffer(struct i40e_ring * rx_ring,const unsigned int size)1790 static struct i40e_rx_buffer *i40e_get_rx_buffer(struct i40e_ring *rx_ring,
1791 						 const unsigned int size)
1792 {
1793 	struct i40e_rx_buffer *rx_buffer;
1794 
1795 	rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
1796 	prefetchw(rx_buffer->page);
1797 
1798 	/* we are reusing so sync this buffer for CPU use */
1799 	dma_sync_single_range_for_cpu(rx_ring->dev,
1800 				      rx_buffer->dma,
1801 				      rx_buffer->page_offset,
1802 				      size,
1803 				      DMA_FROM_DEVICE);
1804 
1805 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
1806 	rx_buffer->pagecnt_bias--;
1807 
1808 	return rx_buffer;
1809 }
1810 
1811 /**
1812  * i40e_construct_skb - Allocate skb and populate it
1813  * @rx_ring: rx descriptor ring to transact packets on
1814  * @rx_buffer: rx buffer to pull data from
1815  * @xdp: xdp_buff pointing to the data
1816  *
1817  * This function allocates an skb.  It then populates it with the page
1818  * data from the current receive descriptor, taking care to set up the
1819  * skb correctly.
1820  */
i40e_construct_skb(struct i40e_ring * rx_ring,struct i40e_rx_buffer * rx_buffer,struct xdp_buff * xdp)1821 static struct sk_buff *i40e_construct_skb(struct i40e_ring *rx_ring,
1822 					  struct i40e_rx_buffer *rx_buffer,
1823 					  struct xdp_buff *xdp)
1824 {
1825 	unsigned int size = xdp->data_end - xdp->data;
1826 #if (PAGE_SIZE < 8192)
1827 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1828 #else
1829 	unsigned int truesize = SKB_DATA_ALIGN(size);
1830 #endif
1831 	unsigned int headlen;
1832 	struct sk_buff *skb;
1833 
1834 	/* prefetch first cache line of first page */
1835 	prefetch(xdp->data);
1836 #if L1_CACHE_BYTES < 128
1837 	prefetch(xdp->data + L1_CACHE_BYTES);
1838 #endif
1839 
1840 	/* allocate a skb to store the frags */
1841 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
1842 			       I40E_RX_HDR_SIZE,
1843 			       GFP_ATOMIC | __GFP_NOWARN);
1844 	if (unlikely(!skb))
1845 		return NULL;
1846 
1847 	/* Determine available headroom for copy */
1848 	headlen = size;
1849 	if (headlen > I40E_RX_HDR_SIZE)
1850 		headlen = eth_get_headlen(xdp->data, I40E_RX_HDR_SIZE);
1851 
1852 	/* align pull length to size of long to optimize memcpy performance */
1853 	memcpy(__skb_put(skb, headlen), xdp->data,
1854 	       ALIGN(headlen, sizeof(long)));
1855 
1856 	/* update all of the pointers */
1857 	size -= headlen;
1858 	if (size) {
1859 		skb_add_rx_frag(skb, 0, rx_buffer->page,
1860 				rx_buffer->page_offset + headlen,
1861 				size, truesize);
1862 
1863 		/* buffer is used by skb, update page_offset */
1864 #if (PAGE_SIZE < 8192)
1865 		rx_buffer->page_offset ^= truesize;
1866 #else
1867 		rx_buffer->page_offset += truesize;
1868 #endif
1869 	} else {
1870 		/* buffer is unused, reset bias back to rx_buffer */
1871 		rx_buffer->pagecnt_bias++;
1872 	}
1873 
1874 	return skb;
1875 }
1876 
1877 /**
1878  * i40e_build_skb - Build skb around an existing buffer
1879  * @rx_ring: Rx descriptor ring to transact packets on
1880  * @rx_buffer: Rx buffer to pull data from
1881  * @xdp: xdp_buff pointing to the data
1882  *
1883  * This function builds an skb around an existing Rx buffer, taking care
1884  * to set up the skb correctly and avoid any memcpy overhead.
1885  */
i40e_build_skb(struct i40e_ring * rx_ring,struct i40e_rx_buffer * rx_buffer,struct xdp_buff * xdp)1886 static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
1887 				      struct i40e_rx_buffer *rx_buffer,
1888 				      struct xdp_buff *xdp)
1889 {
1890 	unsigned int size = xdp->data_end - xdp->data;
1891 #if (PAGE_SIZE < 8192)
1892 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
1893 #else
1894 	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
1895 				SKB_DATA_ALIGN(I40E_SKB_PAD + size);
1896 #endif
1897 	struct sk_buff *skb;
1898 
1899 	/* prefetch first cache line of first page */
1900 	prefetch(xdp->data);
1901 #if L1_CACHE_BYTES < 128
1902 	prefetch(xdp->data + L1_CACHE_BYTES);
1903 #endif
1904 	/* build an skb around the page buffer */
1905 	skb = build_skb(xdp->data_hard_start, truesize);
1906 	if (unlikely(!skb))
1907 		return NULL;
1908 
1909 	/* update pointers within the skb to store the data */
1910 	skb_reserve(skb, I40E_SKB_PAD);
1911 	__skb_put(skb, size);
1912 
1913 	/* buffer is used by skb, update page_offset */
1914 #if (PAGE_SIZE < 8192)
1915 	rx_buffer->page_offset ^= truesize;
1916 #else
1917 	rx_buffer->page_offset += truesize;
1918 #endif
1919 
1920 	return skb;
1921 }
1922 
1923 /**
1924  * i40e_put_rx_buffer - Clean up used buffer and either recycle or free
1925  * @rx_ring: rx descriptor ring to transact packets on
1926  * @rx_buffer: rx buffer to pull data from
1927  *
1928  * This function will clean up the contents of the rx_buffer.  It will
1929  * either recycle the bufer or unmap it and free the associated resources.
1930  */
i40e_put_rx_buffer(struct i40e_ring * rx_ring,struct i40e_rx_buffer * rx_buffer)1931 static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
1932 			       struct i40e_rx_buffer *rx_buffer)
1933 {
1934 	if (i40e_can_reuse_rx_page(rx_buffer)) {
1935 		/* hand second half of page back to the ring */
1936 		i40e_reuse_rx_page(rx_ring, rx_buffer);
1937 		rx_ring->rx_stats.page_reuse_count++;
1938 	} else {
1939 		/* we are not reusing the buffer so unmap it */
1940 		dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
1941 				     i40e_rx_pg_size(rx_ring),
1942 				     DMA_FROM_DEVICE, I40E_RX_DMA_ATTR);
1943 		__page_frag_cache_drain(rx_buffer->page,
1944 					rx_buffer->pagecnt_bias);
1945 	}
1946 
1947 	/* clear contents of buffer_info */
1948 	rx_buffer->page = NULL;
1949 }
1950 
1951 /**
1952  * i40e_is_non_eop - process handling of non-EOP buffers
1953  * @rx_ring: Rx ring being processed
1954  * @rx_desc: Rx descriptor for current buffer
1955  * @skb: Current socket buffer containing buffer in progress
1956  *
1957  * This function updates next to clean.  If the buffer is an EOP buffer
1958  * this function exits returning false, otherwise it will place the
1959  * sk_buff in the next buffer to be chained and return true indicating
1960  * that this is in fact a non-EOP buffer.
1961  **/
i40e_is_non_eop(struct i40e_ring * rx_ring,union i40e_rx_desc * rx_desc,struct sk_buff * skb)1962 static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
1963 			    union i40e_rx_desc *rx_desc,
1964 			    struct sk_buff *skb)
1965 {
1966 	u32 ntc = rx_ring->next_to_clean + 1;
1967 
1968 	/* fetch, update, and store next to clean */
1969 	ntc = (ntc < rx_ring->count) ? ntc : 0;
1970 	rx_ring->next_to_clean = ntc;
1971 
1972 	prefetch(I40E_RX_DESC(rx_ring, ntc));
1973 
1974 	/* if we are the last buffer then there is nothing else to do */
1975 #define I40E_RXD_EOF BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)
1976 	if (likely(i40e_test_staterr(rx_desc, I40E_RXD_EOF)))
1977 		return false;
1978 
1979 	rx_ring->rx_stats.non_eop_descs++;
1980 
1981 	return true;
1982 }
1983 
1984 #define I40E_XDP_PASS 0
1985 #define I40E_XDP_CONSUMED 1
1986 #define I40E_XDP_TX 2
1987 
1988 static int i40e_xmit_xdp_ring(struct xdp_buff *xdp,
1989 			      struct i40e_ring *xdp_ring);
1990 
1991 /**
1992  * i40e_run_xdp - run an XDP program
1993  * @rx_ring: Rx ring being processed
1994  * @xdp: XDP buffer containing the frame
1995  **/
i40e_run_xdp(struct i40e_ring * rx_ring,struct xdp_buff * xdp)1996 static struct sk_buff *i40e_run_xdp(struct i40e_ring *rx_ring,
1997 				    struct xdp_buff *xdp)
1998 {
1999 	int result = I40E_XDP_PASS;
2000 	struct i40e_ring *xdp_ring;
2001 	struct bpf_prog *xdp_prog;
2002 	u32 act;
2003 
2004 	rcu_read_lock();
2005 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
2006 
2007 	if (!xdp_prog)
2008 		goto xdp_out;
2009 
2010 	act = bpf_prog_run_xdp(xdp_prog, xdp);
2011 	switch (act) {
2012 	case XDP_PASS:
2013 		break;
2014 	case XDP_TX:
2015 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2016 		result = i40e_xmit_xdp_ring(xdp, xdp_ring);
2017 		break;
2018 	default:
2019 		bpf_warn_invalid_xdp_action(act);
2020 	case XDP_ABORTED:
2021 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
2022 		/* fallthrough -- handle aborts by dropping packet */
2023 	case XDP_DROP:
2024 		result = I40E_XDP_CONSUMED;
2025 		break;
2026 	}
2027 xdp_out:
2028 	rcu_read_unlock();
2029 	return ERR_PTR(-result);
2030 }
2031 
2032 /**
2033  * i40e_rx_buffer_flip - adjusted rx_buffer to point to an unused region
2034  * @rx_ring: Rx ring
2035  * @rx_buffer: Rx buffer to adjust
2036  * @size: Size of adjustment
2037  **/
i40e_rx_buffer_flip(struct i40e_ring * rx_ring,struct i40e_rx_buffer * rx_buffer,unsigned int size)2038 static void i40e_rx_buffer_flip(struct i40e_ring *rx_ring,
2039 				struct i40e_rx_buffer *rx_buffer,
2040 				unsigned int size)
2041 {
2042 #if (PAGE_SIZE < 8192)
2043 	unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2;
2044 
2045 	rx_buffer->page_offset ^= truesize;
2046 #else
2047 	unsigned int truesize = SKB_DATA_ALIGN(i40e_rx_offset(rx_ring) + size);
2048 
2049 	rx_buffer->page_offset += truesize;
2050 #endif
2051 }
2052 
2053 /**
2054  * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
2055  * @rx_ring: rx descriptor ring to transact packets on
2056  * @budget: Total limit on number of packets to process
2057  *
2058  * This function provides a "bounce buffer" approach to Rx interrupt
2059  * processing.  The advantage to this is that on systems that have
2060  * expensive overhead for IOMMU access this provides a means of avoiding
2061  * it by maintaining the mapping of the page to the system.
2062  *
2063  * Returns amount of work completed
2064  **/
i40e_clean_rx_irq(struct i40e_ring * rx_ring,int budget)2065 static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
2066 {
2067 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
2068 	struct sk_buff *skb = rx_ring->skb;
2069 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
2070 	bool failure = false, xdp_xmit = false;
2071 
2072 	while (likely(total_rx_packets < (unsigned int)budget)) {
2073 		struct i40e_rx_buffer *rx_buffer;
2074 		union i40e_rx_desc *rx_desc;
2075 		struct xdp_buff xdp;
2076 		unsigned int size;
2077 		u16 vlan_tag;
2078 		u8 rx_ptype;
2079 		u64 qword;
2080 
2081 		/* return some buffers to hardware, one at a time is too slow */
2082 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
2083 			failure = failure ||
2084 				  i40e_alloc_rx_buffers(rx_ring, cleaned_count);
2085 			cleaned_count = 0;
2086 		}
2087 
2088 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
2089 
2090 		/* status_error_len will always be zero for unused descriptors
2091 		 * because it's cleared in cleanup, and overlaps with hdr_addr
2092 		 * which is always zero because packet split isn't used, if the
2093 		 * hardware wrote DD then the length will be non-zero
2094 		 */
2095 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2096 
2097 		/* This memory barrier is needed to keep us from reading
2098 		 * any other fields out of the rx_desc until we have
2099 		 * verified the descriptor has been written back.
2100 		 */
2101 		dma_rmb();
2102 
2103 		if (unlikely(i40e_rx_is_programming_status(qword))) {
2104 			i40e_clean_programming_status(rx_ring, rx_desc, qword);
2105 			cleaned_count++;
2106 			continue;
2107 		}
2108 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
2109 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
2110 		if (!size)
2111 			break;
2112 
2113 		i40e_trace(clean_rx_irq, rx_ring, rx_desc, skb);
2114 		rx_buffer = i40e_get_rx_buffer(rx_ring, size);
2115 
2116 		/* retrieve a buffer from the ring */
2117 		if (!skb) {
2118 			xdp.data = page_address(rx_buffer->page) +
2119 				   rx_buffer->page_offset;
2120 			xdp.data_hard_start = xdp.data -
2121 					      i40e_rx_offset(rx_ring);
2122 			xdp.data_end = xdp.data + size;
2123 
2124 			skb = i40e_run_xdp(rx_ring, &xdp);
2125 		}
2126 
2127 		if (IS_ERR(skb)) {
2128 			if (PTR_ERR(skb) == -I40E_XDP_TX) {
2129 				xdp_xmit = true;
2130 				i40e_rx_buffer_flip(rx_ring, rx_buffer, size);
2131 			} else {
2132 				rx_buffer->pagecnt_bias++;
2133 			}
2134 			total_rx_bytes += size;
2135 			total_rx_packets++;
2136 		} else if (skb) {
2137 			i40e_add_rx_frag(rx_ring, rx_buffer, skb, size);
2138 		} else if (ring_uses_build_skb(rx_ring)) {
2139 			skb = i40e_build_skb(rx_ring, rx_buffer, &xdp);
2140 		} else {
2141 			skb = i40e_construct_skb(rx_ring, rx_buffer, &xdp);
2142 		}
2143 
2144 		/* exit if we failed to retrieve a buffer */
2145 		if (!skb) {
2146 			rx_ring->rx_stats.alloc_buff_failed++;
2147 			rx_buffer->pagecnt_bias++;
2148 			break;
2149 		}
2150 
2151 		i40e_put_rx_buffer(rx_ring, rx_buffer);
2152 		cleaned_count++;
2153 
2154 		if (i40e_is_non_eop(rx_ring, rx_desc, skb))
2155 			continue;
2156 
2157 		if (i40e_cleanup_headers(rx_ring, skb, rx_desc)) {
2158 			skb = NULL;
2159 			continue;
2160 		}
2161 
2162 		/* probably a little skewed due to removing CRC */
2163 		total_rx_bytes += skb->len;
2164 
2165 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
2166 		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
2167 			   I40E_RXD_QW1_PTYPE_SHIFT;
2168 
2169 		/* populate checksum, VLAN, and protocol */
2170 		i40e_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
2171 
2172 		vlan_tag = (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) ?
2173 			   le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;
2174 
2175 		i40e_trace(clean_rx_irq_rx, rx_ring, rx_desc, skb);
2176 		i40e_receive_skb(rx_ring, skb, vlan_tag);
2177 		skb = NULL;
2178 
2179 		/* update budget accounting */
2180 		total_rx_packets++;
2181 	}
2182 
2183 	if (xdp_xmit) {
2184 		struct i40e_ring *xdp_ring;
2185 
2186 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
2187 
2188 		/* Force memory writes to complete before letting h/w
2189 		 * know there are new descriptors to fetch.
2190 		 */
2191 		wmb();
2192 
2193 		writel(xdp_ring->next_to_use, xdp_ring->tail);
2194 	}
2195 
2196 	rx_ring->skb = skb;
2197 
2198 	u64_stats_update_begin(&rx_ring->syncp);
2199 	rx_ring->stats.packets += total_rx_packets;
2200 	rx_ring->stats.bytes += total_rx_bytes;
2201 	u64_stats_update_end(&rx_ring->syncp);
2202 	rx_ring->q_vector->rx.total_packets += total_rx_packets;
2203 	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
2204 
2205 	/* guarantee a trip back through this routine if there was a failure */
2206 	return failure ? budget : (int)total_rx_packets;
2207 }
2208 
i40e_buildreg_itr(const int type,const u16 itr)2209 static u32 i40e_buildreg_itr(const int type, const u16 itr)
2210 {
2211 	u32 val;
2212 
2213 	val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
2214 	      /* Don't clear PBA because that can cause lost interrupts that
2215 	       * came in while we were cleaning/polling
2216 	       */
2217 	      (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
2218 	      (itr << I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT);
2219 
2220 	return val;
2221 }
2222 
2223 /* a small macro to shorten up some long lines */
2224 #define INTREG I40E_PFINT_DYN_CTLN
get_rx_itr(struct i40e_vsi * vsi,int idx)2225 static inline int get_rx_itr(struct i40e_vsi *vsi, int idx)
2226 {
2227 	return vsi->rx_rings[idx]->rx_itr_setting;
2228 }
2229 
get_tx_itr(struct i40e_vsi * vsi,int idx)2230 static inline int get_tx_itr(struct i40e_vsi *vsi, int idx)
2231 {
2232 	return vsi->tx_rings[idx]->tx_itr_setting;
2233 }
2234 
2235 /**
2236  * i40e_update_enable_itr - Update itr and re-enable MSIX interrupt
2237  * @vsi: the VSI we care about
2238  * @q_vector: q_vector for which itr is being updated and interrupt enabled
2239  *
2240  **/
i40e_update_enable_itr(struct i40e_vsi * vsi,struct i40e_q_vector * q_vector)2241 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
2242 					  struct i40e_q_vector *q_vector)
2243 {
2244 	struct i40e_hw *hw = &vsi->back->hw;
2245 	bool rx = false, tx = false;
2246 	u32 rxval, txval;
2247 	int vector;
2248 	int idx = q_vector->v_idx;
2249 	int rx_itr_setting, tx_itr_setting;
2250 
2251 	/* If we don't have MSIX, then we only need to re-enable icr0 */
2252 	if (!(vsi->back->flags & I40E_FLAG_MSIX_ENABLED)) {
2253 		i40e_irq_dynamic_enable_icr0(vsi->back, false);
2254 		return;
2255 	}
2256 
2257 	vector = (q_vector->v_idx + vsi->base_vector);
2258 
2259 	/* avoid dynamic calculation if in countdown mode OR if
2260 	 * all dynamic is disabled
2261 	 */
2262 	rxval = txval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
2263 
2264 	rx_itr_setting = get_rx_itr(vsi, idx);
2265 	tx_itr_setting = get_tx_itr(vsi, idx);
2266 
2267 	if (q_vector->itr_countdown > 0 ||
2268 	    (!ITR_IS_DYNAMIC(rx_itr_setting) &&
2269 	     !ITR_IS_DYNAMIC(tx_itr_setting))) {
2270 		goto enable_int;
2271 	}
2272 
2273 	if (ITR_IS_DYNAMIC(rx_itr_setting)) {
2274 		rx = i40e_set_new_dynamic_itr(&q_vector->rx);
2275 		rxval = i40e_buildreg_itr(I40E_RX_ITR, q_vector->rx.itr);
2276 	}
2277 
2278 	if (ITR_IS_DYNAMIC(tx_itr_setting)) {
2279 		tx = i40e_set_new_dynamic_itr(&q_vector->tx);
2280 		txval = i40e_buildreg_itr(I40E_TX_ITR, q_vector->tx.itr);
2281 	}
2282 
2283 	if (rx || tx) {
2284 		/* get the higher of the two ITR adjustments and
2285 		 * use the same value for both ITR registers
2286 		 * when in adaptive mode (Rx and/or Tx)
2287 		 */
2288 		u16 itr = max(q_vector->tx.itr, q_vector->rx.itr);
2289 
2290 		q_vector->tx.itr = q_vector->rx.itr = itr;
2291 		txval = i40e_buildreg_itr(I40E_TX_ITR, itr);
2292 		tx = true;
2293 		rxval = i40e_buildreg_itr(I40E_RX_ITR, itr);
2294 		rx = true;
2295 	}
2296 
2297 	/* only need to enable the interrupt once, but need
2298 	 * to possibly update both ITR values
2299 	 */
2300 	if (rx) {
2301 		/* set the INTENA_MSK_MASK so that this first write
2302 		 * won't actually enable the interrupt, instead just
2303 		 * updating the ITR (it's bit 31 PF and VF)
2304 		 */
2305 		rxval |= BIT(31);
2306 		/* don't check _DOWN because interrupt isn't being enabled */
2307 		wr32(hw, INTREG(vector - 1), rxval);
2308 	}
2309 
2310 enable_int:
2311 	if (!test_bit(__I40E_VSI_DOWN, vsi->state))
2312 		wr32(hw, INTREG(vector - 1), txval);
2313 
2314 	if (q_vector->itr_countdown)
2315 		q_vector->itr_countdown--;
2316 	else
2317 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
2318 }
2319 
2320 /**
2321  * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
2322  * @napi: napi struct with our devices info in it
2323  * @budget: amount of work driver is allowed to do this pass, in packets
2324  *
2325  * This function will clean all queues associated with a q_vector.
2326  *
2327  * Returns the amount of work done
2328  **/
i40e_napi_poll(struct napi_struct * napi,int budget)2329 int i40e_napi_poll(struct napi_struct *napi, int budget)
2330 {
2331 	struct i40e_q_vector *q_vector =
2332 			       container_of(napi, struct i40e_q_vector, napi);
2333 	struct i40e_vsi *vsi = q_vector->vsi;
2334 	struct i40e_ring *ring;
2335 	bool clean_complete = true;
2336 	bool arm_wb = false;
2337 	int budget_per_ring;
2338 	int work_done = 0;
2339 
2340 	if (test_bit(__I40E_VSI_DOWN, vsi->state)) {
2341 		napi_complete(napi);
2342 		return 0;
2343 	}
2344 
2345 	/* Since the actual Tx work is minimal, we can give the Tx a larger
2346 	 * budget and be more aggressive about cleaning up the Tx descriptors.
2347 	 */
2348 	i40e_for_each_ring(ring, q_vector->tx) {
2349 		if (!i40e_clean_tx_irq(vsi, ring, budget)) {
2350 			clean_complete = false;
2351 			continue;
2352 		}
2353 		arm_wb |= ring->arm_wb;
2354 		ring->arm_wb = false;
2355 	}
2356 
2357 	/* Handle case where we are called by netpoll with a budget of 0 */
2358 	if (budget <= 0)
2359 		goto tx_only;
2360 
2361 	/* We attempt to distribute budget to each Rx queue fairly, but don't
2362 	 * allow the budget to go below 1 because that would exit polling early.
2363 	 */
2364 	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
2365 
2366 	i40e_for_each_ring(ring, q_vector->rx) {
2367 		int cleaned = i40e_clean_rx_irq(ring, budget_per_ring);
2368 
2369 		work_done += cleaned;
2370 		/* if we clean as many as budgeted, we must not be done */
2371 		if (cleaned >= budget_per_ring)
2372 			clean_complete = false;
2373 	}
2374 
2375 	/* If work not completed, return budget and polling will return */
2376 	if (!clean_complete) {
2377 		int cpu_id = smp_processor_id();
2378 
2379 		/* It is possible that the interrupt affinity has changed but,
2380 		 * if the cpu is pegged at 100%, polling will never exit while
2381 		 * traffic continues and the interrupt will be stuck on this
2382 		 * cpu.  We check to make sure affinity is correct before we
2383 		 * continue to poll, otherwise we must stop polling so the
2384 		 * interrupt can move to the correct cpu.
2385 		 */
2386 		if (!cpumask_test_cpu(cpu_id, &q_vector->affinity_mask)) {
2387 			/* Tell napi that we are done polling */
2388 			napi_complete_done(napi, work_done);
2389 
2390 			/* Force an interrupt */
2391 			i40e_force_wb(vsi, q_vector);
2392 
2393 			/* Return budget-1 so that polling stops */
2394 			return budget - 1;
2395 		}
2396 tx_only:
2397 		if (arm_wb) {
2398 			q_vector->tx.ring[0].tx_stats.tx_force_wb++;
2399 			i40e_enable_wb_on_itr(vsi, q_vector);
2400 		}
2401 		return budget;
2402 	}
2403 
2404 	if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR)
2405 		q_vector->arm_wb_state = false;
2406 
2407 	/* Work is done so exit the polling mode and re-enable the interrupt */
2408 	napi_complete_done(napi, work_done);
2409 
2410 	i40e_update_enable_itr(vsi, q_vector);
2411 
2412 	return min(work_done, budget - 1);
2413 }
2414 
2415 /**
2416  * i40e_atr - Add a Flow Director ATR filter
2417  * @tx_ring:  ring to add programming descriptor to
2418  * @skb:      send buffer
2419  * @tx_flags: send tx flags
2420  **/
i40e_atr(struct i40e_ring * tx_ring,struct sk_buff * skb,u32 tx_flags)2421 static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
2422 		     u32 tx_flags)
2423 {
2424 	struct i40e_filter_program_desc *fdir_desc;
2425 	struct i40e_pf *pf = tx_ring->vsi->back;
2426 	union {
2427 		unsigned char *network;
2428 		struct iphdr *ipv4;
2429 		struct ipv6hdr *ipv6;
2430 	} hdr;
2431 	struct tcphdr *th;
2432 	unsigned int hlen;
2433 	u32 flex_ptype, dtype_cmd;
2434 	int l4_proto;
2435 	u16 i;
2436 
2437 	/* make sure ATR is enabled */
2438 	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
2439 		return;
2440 
2441 	if (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED)
2442 		return;
2443 
2444 	/* if sampling is disabled do nothing */
2445 	if (!tx_ring->atr_sample_rate)
2446 		return;
2447 
2448 	/* Currently only IPv4/IPv6 with TCP is supported */
2449 	if (!(tx_flags & (I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6)))
2450 		return;
2451 
2452 	/* snag network header to get L4 type and address */
2453 	hdr.network = (tx_flags & I40E_TX_FLAGS_UDP_TUNNEL) ?
2454 		      skb_inner_network_header(skb) : skb_network_header(skb);
2455 
2456 	/* Note: tx_flags gets modified to reflect inner protocols in
2457 	 * tx_enable_csum function if encap is enabled.
2458 	 */
2459 	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2460 		/* access ihl as u8 to avoid unaligned access on ia64 */
2461 		hlen = (hdr.network[0] & 0x0F) << 2;
2462 		l4_proto = hdr.ipv4->protocol;
2463 	} else {
2464 		/* find the start of the innermost ipv6 header */
2465 		unsigned int inner_hlen = hdr.network - skb->data;
2466 		unsigned int h_offset = inner_hlen;
2467 
2468 		/* this function updates h_offset to the end of the header */
2469 		l4_proto =
2470 		  ipv6_find_hdr(skb, &h_offset, IPPROTO_TCP, NULL, NULL);
2471 		/* hlen will contain our best estimate of the tcp header */
2472 		hlen = h_offset - inner_hlen;
2473 	}
2474 
2475 	if (l4_proto != IPPROTO_TCP)
2476 		return;
2477 
2478 	th = (struct tcphdr *)(hdr.network + hlen);
2479 
2480 	/* Due to lack of space, no more new filters can be programmed */
2481 	if (th->syn && (pf->flags & I40E_FLAG_FD_ATR_AUTO_DISABLED))
2482 		return;
2483 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED) {
2484 		/* HW ATR eviction will take care of removing filters on FIN
2485 		 * and RST packets.
2486 		 */
2487 		if (th->fin || th->rst)
2488 			return;
2489 	}
2490 
2491 	tx_ring->atr_count++;
2492 
2493 	/* sample on all syn/fin/rst packets or once every atr sample rate */
2494 	if (!th->fin &&
2495 	    !th->syn &&
2496 	    !th->rst &&
2497 	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
2498 		return;
2499 
2500 	tx_ring->atr_count = 0;
2501 
2502 	/* grab the next descriptor */
2503 	i = tx_ring->next_to_use;
2504 	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
2505 
2506 	i++;
2507 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2508 
2509 	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
2510 		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
2511 	flex_ptype |= (tx_flags & I40E_TX_FLAGS_IPV4) ?
2512 		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
2513 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
2514 		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
2515 		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
2516 
2517 	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
2518 
2519 	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
2520 
2521 	dtype_cmd |= (th->fin || th->rst) ?
2522 		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
2523 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
2524 		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
2525 		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
2526 
2527 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
2528 		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
2529 
2530 	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
2531 		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
2532 
2533 	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
2534 	if (!(tx_flags & I40E_TX_FLAGS_UDP_TUNNEL))
2535 		dtype_cmd |=
2536 			((u32)I40E_FD_ATR_STAT_IDX(pf->hw.pf_id) <<
2537 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2538 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2539 	else
2540 		dtype_cmd |=
2541 			((u32)I40E_FD_ATR_TUNNEL_STAT_IDX(pf->hw.pf_id) <<
2542 			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2543 			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2544 
2545 	if (pf->flags & I40E_FLAG_HW_ATR_EVICT_ENABLED)
2546 		dtype_cmd |= I40E_TXD_FLTR_QW1_ATR_MASK;
2547 
2548 	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
2549 	fdir_desc->rsvd = cpu_to_le32(0);
2550 	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
2551 	fdir_desc->fd_id = cpu_to_le32(0);
2552 }
2553 
2554 /**
2555  * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
2556  * @skb:     send buffer
2557  * @tx_ring: ring to send buffer on
2558  * @flags:   the tx flags to be set
2559  *
2560  * Checks the skb and set up correspondingly several generic transmit flags
2561  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2562  *
2563  * Returns error code indicate the frame should be dropped upon error and the
2564  * otherwise  returns 0 to indicate the flags has been set properly.
2565  **/
i40e_tx_prepare_vlan_flags(struct sk_buff * skb,struct i40e_ring * tx_ring,u32 * flags)2566 static inline int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2567 					     struct i40e_ring *tx_ring,
2568 					     u32 *flags)
2569 {
2570 	__be16 protocol = skb->protocol;
2571 	u32  tx_flags = 0;
2572 
2573 	if (protocol == htons(ETH_P_8021Q) &&
2574 	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
2575 		/* When HW VLAN acceleration is turned off by the user the
2576 		 * stack sets the protocol to 8021q so that the driver
2577 		 * can take any steps required to support the SW only
2578 		 * VLAN handling.  In our case the driver doesn't need
2579 		 * to take any further steps so just set the protocol
2580 		 * to the encapsulated ethertype.
2581 		 */
2582 		skb->protocol = vlan_get_protocol(skb);
2583 		goto out;
2584 	}
2585 
2586 	/* if we have a HW VLAN tag being added, default to the HW one */
2587 	if (skb_vlan_tag_present(skb)) {
2588 		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
2589 		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2590 	/* else if it is a SW VLAN, check the next protocol and store the tag */
2591 	} else if (protocol == htons(ETH_P_8021Q)) {
2592 		struct vlan_hdr *vhdr, _vhdr;
2593 
2594 		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
2595 		if (!vhdr)
2596 			return -EINVAL;
2597 
2598 		protocol = vhdr->h_vlan_encapsulated_proto;
2599 		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
2600 		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
2601 	}
2602 
2603 	if (!(tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED))
2604 		goto out;
2605 
2606 	/* Insert 802.1p priority into VLAN header */
2607 	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
2608 	    (skb->priority != TC_PRIO_CONTROL)) {
2609 		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
2610 		tx_flags |= (skb->priority & 0x7) <<
2611 				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
2612 		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
2613 			struct vlan_ethhdr *vhdr;
2614 			int rc;
2615 
2616 			rc = skb_cow_head(skb, 0);
2617 			if (rc < 0)
2618 				return rc;
2619 			vhdr = (struct vlan_ethhdr *)skb->data;
2620 			vhdr->h_vlan_TCI = htons(tx_flags >>
2621 						 I40E_TX_FLAGS_VLAN_SHIFT);
2622 		} else {
2623 			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2624 		}
2625 	}
2626 
2627 out:
2628 	*flags = tx_flags;
2629 	return 0;
2630 }
2631 
2632 /**
2633  * i40e_tso - set up the tso context descriptor
2634  * @first:    pointer to first Tx buffer for xmit
2635  * @hdr_len:  ptr to the size of the packet header
2636  * @cd_type_cmd_tso_mss: Quad Word 1
2637  *
2638  * Returns 0 if no TSO can happen, 1 if tso is going, or error
2639  **/
i40e_tso(struct i40e_tx_buffer * first,u8 * hdr_len,u64 * cd_type_cmd_tso_mss)2640 static int i40e_tso(struct i40e_tx_buffer *first, u8 *hdr_len,
2641 		    u64 *cd_type_cmd_tso_mss)
2642 {
2643 	struct sk_buff *skb = first->skb;
2644 	u64 cd_cmd, cd_tso_len, cd_mss;
2645 	union {
2646 		struct iphdr *v4;
2647 		struct ipv6hdr *v6;
2648 		unsigned char *hdr;
2649 	} ip;
2650 	union {
2651 		struct tcphdr *tcp;
2652 		struct udphdr *udp;
2653 		unsigned char *hdr;
2654 	} l4;
2655 	u32 paylen, l4_offset;
2656 	u16 gso_segs, gso_size;
2657 	int err;
2658 
2659 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2660 		return 0;
2661 
2662 	if (!skb_is_gso(skb))
2663 		return 0;
2664 
2665 	err = skb_cow_head(skb, 0);
2666 	if (err < 0)
2667 		return err;
2668 
2669 	ip.hdr = skb_network_header(skb);
2670 	l4.hdr = skb_transport_header(skb);
2671 
2672 	/* initialize outer IP header fields */
2673 	if (ip.v4->version == 4) {
2674 		ip.v4->tot_len = 0;
2675 		ip.v4->check = 0;
2676 	} else {
2677 		ip.v6->payload_len = 0;
2678 	}
2679 
2680 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2681 					 SKB_GSO_GRE_CSUM |
2682 					 SKB_GSO_IPXIP4 |
2683 					 SKB_GSO_IPXIP6 |
2684 					 SKB_GSO_UDP_TUNNEL |
2685 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2686 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2687 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2688 			l4.udp->len = 0;
2689 
2690 			/* determine offset of outer transport header */
2691 			l4_offset = l4.hdr - skb->data;
2692 
2693 			/* remove payload length from outer checksum */
2694 			paylen = skb->len - l4_offset;
2695 			csum_replace_by_diff(&l4.udp->check,
2696 					     (__force __wsum)htonl(paylen));
2697 		}
2698 
2699 		/* reset pointers to inner headers */
2700 		ip.hdr = skb_inner_network_header(skb);
2701 		l4.hdr = skb_inner_transport_header(skb);
2702 
2703 		/* initialize inner IP header fields */
2704 		if (ip.v4->version == 4) {
2705 			ip.v4->tot_len = 0;
2706 			ip.v4->check = 0;
2707 		} else {
2708 			ip.v6->payload_len = 0;
2709 		}
2710 	}
2711 
2712 	/* determine offset of inner transport header */
2713 	l4_offset = l4.hdr - skb->data;
2714 
2715 	/* remove payload length from inner checksum */
2716 	paylen = skb->len - l4_offset;
2717 	csum_replace_by_diff(&l4.tcp->check, (__force __wsum)htonl(paylen));
2718 
2719 	/* compute length of segmentation header */
2720 	*hdr_len = (l4.tcp->doff * 4) + l4_offset;
2721 
2722 	/* pull values out of skb_shinfo */
2723 	gso_size = skb_shinfo(skb)->gso_size;
2724 	gso_segs = skb_shinfo(skb)->gso_segs;
2725 
2726 	/* update GSO size and bytecount with header size */
2727 	first->gso_segs = gso_segs;
2728 	first->bytecount += (first->gso_segs - 1) * *hdr_len;
2729 
2730 	/* find the field values */
2731 	cd_cmd = I40E_TX_CTX_DESC_TSO;
2732 	cd_tso_len = skb->len - *hdr_len;
2733 	cd_mss = gso_size;
2734 	*cd_type_cmd_tso_mss |= (cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
2735 				(cd_tso_len << I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
2736 				(cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
2737 	return 1;
2738 }
2739 
2740 /**
2741  * i40e_tsyn - set up the tsyn context descriptor
2742  * @tx_ring:  ptr to the ring to send
2743  * @skb:      ptr to the skb we're sending
2744  * @tx_flags: the collected send information
2745  * @cd_type_cmd_tso_mss: Quad Word 1
2746  *
2747  * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
2748  **/
i40e_tsyn(struct i40e_ring * tx_ring,struct sk_buff * skb,u32 tx_flags,u64 * cd_type_cmd_tso_mss)2749 static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
2750 		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
2751 {
2752 	struct i40e_pf *pf;
2753 
2754 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2755 		return 0;
2756 
2757 	/* Tx timestamps cannot be sampled when doing TSO */
2758 	if (tx_flags & I40E_TX_FLAGS_TSO)
2759 		return 0;
2760 
2761 	/* only timestamp the outbound packet if the user has requested it and
2762 	 * we are not already transmitting a packet to be timestamped
2763 	 */
2764 	pf = i40e_netdev_to_pf(tx_ring->netdev);
2765 	if (!(pf->flags & I40E_FLAG_PTP))
2766 		return 0;
2767 
2768 	if (pf->ptp_tx &&
2769 	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, pf->state)) {
2770 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2771 		pf->ptp_tx_start = jiffies;
2772 		pf->ptp_tx_skb = skb_get(skb);
2773 	} else {
2774 		pf->tx_hwtstamp_skipped++;
2775 		return 0;
2776 	}
2777 
2778 	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
2779 				I40E_TXD_CTX_QW1_CMD_SHIFT;
2780 
2781 	return 1;
2782 }
2783 
2784 /**
2785  * i40e_tx_enable_csum - Enable Tx checksum offloads
2786  * @skb: send buffer
2787  * @tx_flags: pointer to Tx flags currently set
2788  * @td_cmd: Tx descriptor command bits to set
2789  * @td_offset: Tx descriptor header offsets to set
2790  * @tx_ring: Tx descriptor ring
2791  * @cd_tunneling: ptr to context desc bits
2792  **/
i40e_tx_enable_csum(struct sk_buff * skb,u32 * tx_flags,u32 * td_cmd,u32 * td_offset,struct i40e_ring * tx_ring,u32 * cd_tunneling)2793 static int i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
2794 			       u32 *td_cmd, u32 *td_offset,
2795 			       struct i40e_ring *tx_ring,
2796 			       u32 *cd_tunneling)
2797 {
2798 	union {
2799 		struct iphdr *v4;
2800 		struct ipv6hdr *v6;
2801 		unsigned char *hdr;
2802 	} ip;
2803 	union {
2804 		struct tcphdr *tcp;
2805 		struct udphdr *udp;
2806 		unsigned char *hdr;
2807 	} l4;
2808 	unsigned char *exthdr;
2809 	u32 offset, cmd = 0;
2810 	__be16 frag_off;
2811 	u8 l4_proto = 0;
2812 
2813 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2814 		return 0;
2815 
2816 	ip.hdr = skb_network_header(skb);
2817 	l4.hdr = skb_transport_header(skb);
2818 
2819 	/* compute outer L2 header size */
2820 	offset = ((ip.hdr - skb->data) / 2) << I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
2821 
2822 	if (skb->encapsulation) {
2823 		u32 tunnel = 0;
2824 		/* define outer network header type */
2825 		if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2826 			tunnel |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2827 				  I40E_TX_CTX_EXT_IP_IPV4 :
2828 				  I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
2829 
2830 			l4_proto = ip.v4->protocol;
2831 		} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2832 			tunnel |= I40E_TX_CTX_EXT_IP_IPV6;
2833 
2834 			exthdr = ip.hdr + sizeof(*ip.v6);
2835 			l4_proto = ip.v6->nexthdr;
2836 			if (l4.hdr != exthdr)
2837 				ipv6_skip_exthdr(skb, exthdr - skb->data,
2838 						 &l4_proto, &frag_off);
2839 		}
2840 
2841 		/* define outer transport */
2842 		switch (l4_proto) {
2843 		case IPPROTO_UDP:
2844 			tunnel |= I40E_TXD_CTX_UDP_TUNNELING;
2845 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2846 			break;
2847 		case IPPROTO_GRE:
2848 			tunnel |= I40E_TXD_CTX_GRE_TUNNELING;
2849 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2850 			break;
2851 		case IPPROTO_IPIP:
2852 		case IPPROTO_IPV6:
2853 			*tx_flags |= I40E_TX_FLAGS_UDP_TUNNEL;
2854 			l4.hdr = skb_inner_network_header(skb);
2855 			break;
2856 		default:
2857 			if (*tx_flags & I40E_TX_FLAGS_TSO)
2858 				return -1;
2859 
2860 			skb_checksum_help(skb);
2861 			return 0;
2862 		}
2863 
2864 		/* compute outer L3 header size */
2865 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
2866 			  I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT;
2867 
2868 		/* switch IP header pointer from outer to inner header */
2869 		ip.hdr = skb_inner_network_header(skb);
2870 
2871 		/* compute tunnel header size */
2872 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
2873 			  I40E_TXD_CTX_QW0_NATLEN_SHIFT;
2874 
2875 		/* indicate if we need to offload outer UDP header */
2876 		if ((*tx_flags & I40E_TX_FLAGS_TSO) &&
2877 		    !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2878 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
2879 			tunnel |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
2880 
2881 		/* record tunnel offload values */
2882 		*cd_tunneling |= tunnel;
2883 
2884 		/* switch L4 header pointer from outer to inner */
2885 		l4.hdr = skb_inner_transport_header(skb);
2886 		l4_proto = 0;
2887 
2888 		/* reset type as we transition from outer to inner headers */
2889 		*tx_flags &= ~(I40E_TX_FLAGS_IPV4 | I40E_TX_FLAGS_IPV6);
2890 		if (ip.v4->version == 4)
2891 			*tx_flags |= I40E_TX_FLAGS_IPV4;
2892 		if (ip.v6->version == 6)
2893 			*tx_flags |= I40E_TX_FLAGS_IPV6;
2894 	}
2895 
2896 	/* Enable IP checksum offloads */
2897 	if (*tx_flags & I40E_TX_FLAGS_IPV4) {
2898 		l4_proto = ip.v4->protocol;
2899 		/* the stack computes the IP header already, the only time we
2900 		 * need the hardware to recompute it is in the case of TSO.
2901 		 */
2902 		cmd |= (*tx_flags & I40E_TX_FLAGS_TSO) ?
2903 		       I40E_TX_DESC_CMD_IIPT_IPV4_CSUM :
2904 		       I40E_TX_DESC_CMD_IIPT_IPV4;
2905 	} else if (*tx_flags & I40E_TX_FLAGS_IPV6) {
2906 		cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
2907 
2908 		exthdr = ip.hdr + sizeof(*ip.v6);
2909 		l4_proto = ip.v6->nexthdr;
2910 		if (l4.hdr != exthdr)
2911 			ipv6_skip_exthdr(skb, exthdr - skb->data,
2912 					 &l4_proto, &frag_off);
2913 	}
2914 
2915 	/* compute inner L3 header size */
2916 	offset |= ((l4.hdr - ip.hdr) / 4) << I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2917 
2918 	/* Enable L4 checksum offloads */
2919 	switch (l4_proto) {
2920 	case IPPROTO_TCP:
2921 		/* enable checksum offloads */
2922 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
2923 		offset |= l4.tcp->doff << I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2924 		break;
2925 	case IPPROTO_SCTP:
2926 		/* enable SCTP checksum offload */
2927 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
2928 		offset |= (sizeof(struct sctphdr) >> 2) <<
2929 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2930 		break;
2931 	case IPPROTO_UDP:
2932 		/* enable UDP checksum offload */
2933 		cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
2934 		offset |= (sizeof(struct udphdr) >> 2) <<
2935 			  I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2936 		break;
2937 	default:
2938 		if (*tx_flags & I40E_TX_FLAGS_TSO)
2939 			return -1;
2940 		skb_checksum_help(skb);
2941 		return 0;
2942 	}
2943 
2944 	*td_cmd |= cmd;
2945 	*td_offset |= offset;
2946 
2947 	return 1;
2948 }
2949 
2950 /**
2951  * i40e_create_tx_ctx Build the Tx context descriptor
2952  * @tx_ring:  ring to create the descriptor on
2953  * @cd_type_cmd_tso_mss: Quad Word 1
2954  * @cd_tunneling: Quad Word 0 - bits 0-31
2955  * @cd_l2tag2: Quad Word 0 - bits 32-63
2956  **/
i40e_create_tx_ctx(struct i40e_ring * tx_ring,const u64 cd_type_cmd_tso_mss,const u32 cd_tunneling,const u32 cd_l2tag2)2957 static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
2958 			       const u64 cd_type_cmd_tso_mss,
2959 			       const u32 cd_tunneling, const u32 cd_l2tag2)
2960 {
2961 	struct i40e_tx_context_desc *context_desc;
2962 	int i = tx_ring->next_to_use;
2963 
2964 	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
2965 	    !cd_tunneling && !cd_l2tag2)
2966 		return;
2967 
2968 	/* grab the next descriptor */
2969 	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
2970 
2971 	i++;
2972 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2973 
2974 	/* cpu_to_le32 and assign to struct fields */
2975 	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2976 	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2977 	context_desc->rsvd = cpu_to_le16(0);
2978 	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2979 }
2980 
2981 /**
2982  * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2983  * @tx_ring: the ring to be checked
2984  * @size:    the size buffer we want to assure is available
2985  *
2986  * Returns -EBUSY if a stop is needed, else 0
2987  **/
__i40e_maybe_stop_tx(struct i40e_ring * tx_ring,int size)2988 int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2989 {
2990 	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2991 	/* Memory barrier before checking head and tail */
2992 	smp_mb();
2993 
2994 	/* Check again in a case another CPU has just made room available. */
2995 	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2996 		return -EBUSY;
2997 
2998 	/* A reprieve! - use start_queue because it doesn't call schedule */
2999 	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
3000 	++tx_ring->tx_stats.restart_queue;
3001 	return 0;
3002 }
3003 
3004 /**
3005  * __i40e_chk_linearize - Check if there are more than 8 buffers per packet
3006  * @skb:      send buffer
3007  *
3008  * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
3009  * and so we need to figure out the cases where we need to linearize the skb.
3010  *
3011  * For TSO we need to count the TSO header and segment payload separately.
3012  * As such we need to check cases where we have 7 fragments or more as we
3013  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
3014  * the segment payload in the first descriptor, and another 7 for the
3015  * fragments.
3016  **/
__i40e_chk_linearize(struct sk_buff * skb)3017 bool __i40e_chk_linearize(struct sk_buff *skb)
3018 {
3019 	const struct skb_frag_struct *frag, *stale;
3020 	int nr_frags, sum;
3021 
3022 	/* no need to check if number of frags is less than 7 */
3023 	nr_frags = skb_shinfo(skb)->nr_frags;
3024 	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
3025 		return false;
3026 
3027 	/* We need to walk through the list and validate that each group
3028 	 * of 6 fragments totals at least gso_size.
3029 	 */
3030 	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
3031 	frag = &skb_shinfo(skb)->frags[0];
3032 
3033 	/* Initialize size to the negative value of gso_size minus 1.  We
3034 	 * use this as the worst case scenerio in which the frag ahead
3035 	 * of us only provides one byte which is why we are limited to 6
3036 	 * descriptors for a single transmit as the header and previous
3037 	 * fragment are already consuming 2 descriptors.
3038 	 */
3039 	sum = 1 - skb_shinfo(skb)->gso_size;
3040 
3041 	/* Add size of frags 0 through 4 to create our initial sum */
3042 	sum += skb_frag_size(frag++);
3043 	sum += skb_frag_size(frag++);
3044 	sum += skb_frag_size(frag++);
3045 	sum += skb_frag_size(frag++);
3046 	sum += skb_frag_size(frag++);
3047 
3048 	/* Walk through fragments adding latest fragment, testing it, and
3049 	 * then removing stale fragments from the sum.
3050 	 */
3051 	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
3052 		int stale_size = skb_frag_size(stale);
3053 
3054 		sum += skb_frag_size(frag++);
3055 
3056 		/* The stale fragment may present us with a smaller
3057 		 * descriptor than the actual fragment size. To account
3058 		 * for that we need to remove all the data on the front and
3059 		 * figure out what the remainder would be in the last
3060 		 * descriptor associated with the fragment.
3061 		 */
3062 		if (stale_size > I40E_MAX_DATA_PER_TXD) {
3063 			int align_pad = -(stale->page_offset) &
3064 					(I40E_MAX_READ_REQ_SIZE - 1);
3065 
3066 			sum -= align_pad;
3067 			stale_size -= align_pad;
3068 
3069 			do {
3070 				sum -= I40E_MAX_DATA_PER_TXD_ALIGNED;
3071 				stale_size -= I40E_MAX_DATA_PER_TXD_ALIGNED;
3072 			} while (stale_size > I40E_MAX_DATA_PER_TXD);
3073 		}
3074 
3075 		/* if sum is negative we failed to make sufficient progress */
3076 		if (sum < 0)
3077 			return true;
3078 
3079 		if (!nr_frags--)
3080 			break;
3081 
3082 		sum -= stale_size;
3083 	}
3084 
3085 	return false;
3086 }
3087 
3088 /**
3089  * i40e_tx_map - Build the Tx descriptor
3090  * @tx_ring:  ring to send buffer on
3091  * @skb:      send buffer
3092  * @first:    first buffer info buffer to use
3093  * @tx_flags: collected send information
3094  * @hdr_len:  size of the packet header
3095  * @td_cmd:   the command field in the descriptor
3096  * @td_offset: offset for checksum or crc
3097  *
3098  * Returns 0 on success, -1 on failure to DMA
3099  **/
i40e_tx_map(struct i40e_ring * tx_ring,struct sk_buff * skb,struct i40e_tx_buffer * first,u32 tx_flags,const u8 hdr_len,u32 td_cmd,u32 td_offset)3100 static inline int i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
3101 			      struct i40e_tx_buffer *first, u32 tx_flags,
3102 			      const u8 hdr_len, u32 td_cmd, u32 td_offset)
3103 {
3104 	unsigned int data_len = skb->data_len;
3105 	unsigned int size = skb_headlen(skb);
3106 	struct skb_frag_struct *frag;
3107 	struct i40e_tx_buffer *tx_bi;
3108 	struct i40e_tx_desc *tx_desc;
3109 	u16 i = tx_ring->next_to_use;
3110 	u32 td_tag = 0;
3111 	dma_addr_t dma;
3112 	u16 desc_count = 1;
3113 
3114 	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
3115 		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
3116 		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
3117 			 I40E_TX_FLAGS_VLAN_SHIFT;
3118 	}
3119 
3120 	first->tx_flags = tx_flags;
3121 
3122 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
3123 
3124 	tx_desc = I40E_TX_DESC(tx_ring, i);
3125 	tx_bi = first;
3126 
3127 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
3128 		unsigned int max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3129 
3130 		if (dma_mapping_error(tx_ring->dev, dma))
3131 			goto dma_error;
3132 
3133 		/* record length, and DMA address */
3134 		dma_unmap_len_set(tx_bi, len, size);
3135 		dma_unmap_addr_set(tx_bi, dma, dma);
3136 
3137 		/* align size to end of page */
3138 		max_data += -dma & (I40E_MAX_READ_REQ_SIZE - 1);
3139 		tx_desc->buffer_addr = cpu_to_le64(dma);
3140 
3141 		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
3142 			tx_desc->cmd_type_offset_bsz =
3143 				build_ctob(td_cmd, td_offset,
3144 					   max_data, td_tag);
3145 
3146 			tx_desc++;
3147 			i++;
3148 			desc_count++;
3149 
3150 			if (i == tx_ring->count) {
3151 				tx_desc = I40E_TX_DESC(tx_ring, 0);
3152 				i = 0;
3153 			}
3154 
3155 			dma += max_data;
3156 			size -= max_data;
3157 
3158 			max_data = I40E_MAX_DATA_PER_TXD_ALIGNED;
3159 			tx_desc->buffer_addr = cpu_to_le64(dma);
3160 		}
3161 
3162 		if (likely(!data_len))
3163 			break;
3164 
3165 		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
3166 							  size, td_tag);
3167 
3168 		tx_desc++;
3169 		i++;
3170 		desc_count++;
3171 
3172 		if (i == tx_ring->count) {
3173 			tx_desc = I40E_TX_DESC(tx_ring, 0);
3174 			i = 0;
3175 		}
3176 
3177 		size = skb_frag_size(frag);
3178 		data_len -= size;
3179 
3180 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
3181 				       DMA_TO_DEVICE);
3182 
3183 		tx_bi = &tx_ring->tx_bi[i];
3184 	}
3185 
3186 	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
3187 
3188 	i++;
3189 	if (i == tx_ring->count)
3190 		i = 0;
3191 
3192 	tx_ring->next_to_use = i;
3193 
3194 	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
3195 
3196 	/* write last descriptor with EOP bit */
3197 	td_cmd |= I40E_TX_DESC_CMD_EOP;
3198 
3199 	/* We can OR these values together as they both are checked against
3200 	 * 4 below and at this point desc_count will be used as a boolean value
3201 	 * after this if/else block.
3202 	 */
3203 	desc_count |= ++tx_ring->packet_stride;
3204 
3205 	/* Algorithm to optimize tail and RS bit setting:
3206 	 * if queue is stopped
3207 	 *	mark RS bit
3208 	 *	reset packet counter
3209 	 * else if xmit_more is supported and is true
3210 	 *	advance packet counter to 4
3211 	 *	reset desc_count to 0
3212 	 *
3213 	 * if desc_count >= 4
3214 	 *	mark RS bit
3215 	 *	reset packet counter
3216 	 * if desc_count > 0
3217 	 *	update tail
3218 	 *
3219 	 * Note: If there are less than 4 descriptors
3220 	 * pending and interrupts were disabled the service task will
3221 	 * trigger a force WB.
3222 	 */
3223 	if (netif_xmit_stopped(txring_txq(tx_ring))) {
3224 		goto do_rs;
3225 	} else if (skb->xmit_more) {
3226 		/* set stride to arm on next packet and reset desc_count */
3227 		tx_ring->packet_stride = WB_STRIDE;
3228 		desc_count = 0;
3229 	} else if (desc_count >= WB_STRIDE) {
3230 do_rs:
3231 		/* write last descriptor with RS bit set */
3232 		td_cmd |= I40E_TX_DESC_CMD_RS;
3233 		tx_ring->packet_stride = 0;
3234 	}
3235 
3236 	tx_desc->cmd_type_offset_bsz =
3237 			build_ctob(td_cmd, td_offset, size, td_tag);
3238 
3239 	/* Force memory writes to complete before letting h/w know there
3240 	 * are new descriptors to fetch.
3241 	 *
3242 	 * We also use this memory barrier to make certain all of the
3243 	 * status bits have been updated before next_to_watch is written.
3244 	 */
3245 	wmb();
3246 
3247 	/* set next_to_watch value indicating a packet is present */
3248 	first->next_to_watch = tx_desc;
3249 
3250 	/* notify HW of packet */
3251 	if (desc_count) {
3252 		writel(i, tx_ring->tail);
3253 
3254 		/* we need this if more than one processor can write to our tail
3255 		 * at a time, it synchronizes IO on IA64/Altix systems
3256 		 */
3257 		mmiowb();
3258 	}
3259 
3260 	return 0;
3261 
3262 dma_error:
3263 	dev_info(tx_ring->dev, "TX DMA map failed\n");
3264 
3265 	/* clear dma mappings for failed tx_bi map */
3266 	for (;;) {
3267 		tx_bi = &tx_ring->tx_bi[i];
3268 		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
3269 		if (tx_bi == first)
3270 			break;
3271 		if (i == 0)
3272 			i = tx_ring->count;
3273 		i--;
3274 	}
3275 
3276 	tx_ring->next_to_use = i;
3277 
3278 	return -1;
3279 }
3280 
3281 /**
3282  * i40e_xmit_xdp_ring - transmits an XDP buffer to an XDP Tx ring
3283  * @xdp: data to transmit
3284  * @xdp_ring: XDP Tx ring
3285  **/
i40e_xmit_xdp_ring(struct xdp_buff * xdp,struct i40e_ring * xdp_ring)3286 static int i40e_xmit_xdp_ring(struct xdp_buff *xdp,
3287 			      struct i40e_ring *xdp_ring)
3288 {
3289 	u32 size = xdp->data_end - xdp->data;
3290 	u16 i = xdp_ring->next_to_use;
3291 	struct i40e_tx_buffer *tx_bi;
3292 	struct i40e_tx_desc *tx_desc;
3293 	dma_addr_t dma;
3294 
3295 	if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
3296 		xdp_ring->tx_stats.tx_busy++;
3297 		return I40E_XDP_CONSUMED;
3298 	}
3299 
3300 	dma = dma_map_single(xdp_ring->dev, xdp->data, size, DMA_TO_DEVICE);
3301 	if (dma_mapping_error(xdp_ring->dev, dma))
3302 		return I40E_XDP_CONSUMED;
3303 
3304 	tx_bi = &xdp_ring->tx_bi[i];
3305 	tx_bi->bytecount = size;
3306 	tx_bi->gso_segs = 1;
3307 	tx_bi->raw_buf = xdp->data;
3308 
3309 	/* record length, and DMA address */
3310 	dma_unmap_len_set(tx_bi, len, size);
3311 	dma_unmap_addr_set(tx_bi, dma, dma);
3312 
3313 	tx_desc = I40E_TX_DESC(xdp_ring, i);
3314 	tx_desc->buffer_addr = cpu_to_le64(dma);
3315 	tx_desc->cmd_type_offset_bsz = build_ctob(I40E_TX_DESC_CMD_ICRC
3316 						  | I40E_TXD_CMD,
3317 						  0, size, 0);
3318 
3319 	/* Make certain all of the status bits have been updated
3320 	 * before next_to_watch is written.
3321 	 */
3322 	smp_wmb();
3323 
3324 	i++;
3325 	if (i == xdp_ring->count)
3326 		i = 0;
3327 
3328 	tx_bi->next_to_watch = tx_desc;
3329 	xdp_ring->next_to_use = i;
3330 
3331 	return I40E_XDP_TX;
3332 }
3333 
3334 /**
3335  * i40e_xmit_frame_ring - Sends buffer on Tx ring
3336  * @skb:     send buffer
3337  * @tx_ring: ring to send buffer on
3338  *
3339  * Returns NETDEV_TX_OK if sent, else an error code
3340  **/
i40e_xmit_frame_ring(struct sk_buff * skb,struct i40e_ring * tx_ring)3341 static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
3342 					struct i40e_ring *tx_ring)
3343 {
3344 	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
3345 	u32 cd_tunneling = 0, cd_l2tag2 = 0;
3346 	struct i40e_tx_buffer *first;
3347 	u32 td_offset = 0;
3348 	u32 tx_flags = 0;
3349 	__be16 protocol;
3350 	u32 td_cmd = 0;
3351 	u8 hdr_len = 0;
3352 	int tso, count;
3353 	int tsyn;
3354 
3355 	/* prefetch the data, we'll need it later */
3356 	prefetch(skb->data);
3357 
3358 	i40e_trace(xmit_frame_ring, skb, tx_ring);
3359 
3360 	count = i40e_xmit_descriptor_count(skb);
3361 	if (i40e_chk_linearize(skb, count)) {
3362 		if (__skb_linearize(skb)) {
3363 			dev_kfree_skb_any(skb);
3364 			return NETDEV_TX_OK;
3365 		}
3366 		count = i40e_txd_use_count(skb->len);
3367 		tx_ring->tx_stats.tx_linearize++;
3368 	}
3369 
3370 	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
3371 	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
3372 	 *       + 4 desc gap to avoid the cache line where head is,
3373 	 *       + 1 desc for context descriptor,
3374 	 * otherwise try next time
3375 	 */
3376 	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
3377 		tx_ring->tx_stats.tx_busy++;
3378 		return NETDEV_TX_BUSY;
3379 	}
3380 
3381 	/* record the location of the first descriptor for this packet */
3382 	first = &tx_ring->tx_bi[tx_ring->next_to_use];
3383 	first->skb = skb;
3384 	first->bytecount = skb->len;
3385 	first->gso_segs = 1;
3386 
3387 	/* prepare the xmit flags */
3388 	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
3389 		goto out_drop;
3390 
3391 	/* obtain protocol of skb */
3392 	protocol = vlan_get_protocol(skb);
3393 
3394 	/* setup IPv4/IPv6 offloads */
3395 	if (protocol == htons(ETH_P_IP))
3396 		tx_flags |= I40E_TX_FLAGS_IPV4;
3397 	else if (protocol == htons(ETH_P_IPV6))
3398 		tx_flags |= I40E_TX_FLAGS_IPV6;
3399 
3400 	tso = i40e_tso(first, &hdr_len, &cd_type_cmd_tso_mss);
3401 
3402 	if (tso < 0)
3403 		goto out_drop;
3404 	else if (tso)
3405 		tx_flags |= I40E_TX_FLAGS_TSO;
3406 
3407 	/* Always offload the checksum, since it's in the data descriptor */
3408 	tso = i40e_tx_enable_csum(skb, &tx_flags, &td_cmd, &td_offset,
3409 				  tx_ring, &cd_tunneling);
3410 	if (tso < 0)
3411 		goto out_drop;
3412 
3413 	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
3414 
3415 	if (tsyn)
3416 		tx_flags |= I40E_TX_FLAGS_TSYN;
3417 
3418 	skb_tx_timestamp(skb);
3419 
3420 	/* always enable CRC insertion offload */
3421 	td_cmd |= I40E_TX_DESC_CMD_ICRC;
3422 
3423 	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
3424 			   cd_tunneling, cd_l2tag2);
3425 
3426 	/* Add Flow Director ATR if it's enabled.
3427 	 *
3428 	 * NOTE: this must always be directly before the data descriptor.
3429 	 */
3430 	i40e_atr(tx_ring, skb, tx_flags);
3431 
3432 	if (i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
3433 			td_cmd, td_offset))
3434 		goto cleanup_tx_tstamp;
3435 
3436 	return NETDEV_TX_OK;
3437 
3438 out_drop:
3439 	i40e_trace(xmit_frame_ring_drop, first->skb, tx_ring);
3440 	dev_kfree_skb_any(first->skb);
3441 	first->skb = NULL;
3442 cleanup_tx_tstamp:
3443 	if (unlikely(tx_flags & I40E_TX_FLAGS_TSYN)) {
3444 		struct i40e_pf *pf = i40e_netdev_to_pf(tx_ring->netdev);
3445 
3446 		dev_kfree_skb_any(pf->ptp_tx_skb);
3447 		pf->ptp_tx_skb = NULL;
3448 		clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, pf->state);
3449 	}
3450 
3451 	return NETDEV_TX_OK;
3452 }
3453 
3454 /**
3455  * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
3456  * @skb:    send buffer
3457  * @netdev: network interface device structure
3458  *
3459  * Returns NETDEV_TX_OK if sent, else an error code
3460  **/
i40e_lan_xmit_frame(struct sk_buff * skb,struct net_device * netdev)3461 netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
3462 {
3463 	struct i40e_netdev_priv *np = netdev_priv(netdev);
3464 	struct i40e_vsi *vsi = np->vsi;
3465 	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
3466 
3467 	/* hardware can't handle really short frames, hardware padding works
3468 	 * beyond this point
3469 	 */
3470 	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
3471 		return NETDEV_TX_OK;
3472 
3473 	return i40e_xmit_frame_ring(skb, tx_ring);
3474 }
3475