1/*******************************************************************************
2 *
3 * Intel Ethernet Controller XL710 Family Linux Driver
4 * Copyright(c) 2013 - 2014 Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program.  If not, see <http://www.gnu.org/licenses/>.
17 *
18 * The full GNU General Public License is included in this distribution in
19 * the file called "COPYING".
20 *
21 * Contact Information:
22 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24 *
25 ******************************************************************************/
26
27#include <linux/prefetch.h>
28#include <net/busy_poll.h>
29#include "i40e.h"
30#include "i40e_prototype.h"
31
32static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
33				u32 td_tag)
34{
35	return cpu_to_le64(I40E_TX_DESC_DTYPE_DATA |
36			   ((u64)td_cmd  << I40E_TXD_QW1_CMD_SHIFT) |
37			   ((u64)td_offset << I40E_TXD_QW1_OFFSET_SHIFT) |
38			   ((u64)size  << I40E_TXD_QW1_TX_BUF_SZ_SHIFT) |
39			   ((u64)td_tag  << I40E_TXD_QW1_L2TAG1_SHIFT));
40}
41
42#define I40E_TXD_CMD (I40E_TX_DESC_CMD_EOP | I40E_TX_DESC_CMD_RS)
43#define I40E_FD_CLEAN_DELAY 10
44/**
45 * i40e_program_fdir_filter - Program a Flow Director filter
46 * @fdir_data: Packet data that will be filter parameters
47 * @raw_packet: the pre-allocated packet buffer for FDir
48 * @pf: The PF pointer
49 * @add: True for add/update, False for remove
50 **/
51int i40e_program_fdir_filter(struct i40e_fdir_filter *fdir_data, u8 *raw_packet,
52			     struct i40e_pf *pf, bool add)
53{
54	struct i40e_filter_program_desc *fdir_desc;
55	struct i40e_tx_buffer *tx_buf, *first;
56	struct i40e_tx_desc *tx_desc;
57	struct i40e_ring *tx_ring;
58	unsigned int fpt, dcc;
59	struct i40e_vsi *vsi;
60	struct device *dev;
61	dma_addr_t dma;
62	u32 td_cmd = 0;
63	u16 delay = 0;
64	u16 i;
65
66	/* find existing FDIR VSI */
67	vsi = NULL;
68	for (i = 0; i < pf->num_alloc_vsi; i++)
69		if (pf->vsi[i] && pf->vsi[i]->type == I40E_VSI_FDIR)
70			vsi = pf->vsi[i];
71	if (!vsi)
72		return -ENOENT;
73
74	tx_ring = vsi->tx_rings[0];
75	dev = tx_ring->dev;
76
77	/* we need two descriptors to add/del a filter and we can wait */
78	do {
79		if (I40E_DESC_UNUSED(tx_ring) > 1)
80			break;
81		msleep_interruptible(1);
82		delay++;
83	} while (delay < I40E_FD_CLEAN_DELAY);
84
85	if (!(I40E_DESC_UNUSED(tx_ring) > 1))
86		return -EAGAIN;
87
88	dma = dma_map_single(dev, raw_packet,
89			     I40E_FDIR_MAX_RAW_PACKET_SIZE, DMA_TO_DEVICE);
90	if (dma_mapping_error(dev, dma))
91		goto dma_fail;
92
93	/* grab the next descriptor */
94	i = tx_ring->next_to_use;
95	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
96	first = &tx_ring->tx_bi[i];
97	memset(first, 0, sizeof(struct i40e_tx_buffer));
98
99	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
100
101	fpt = (fdir_data->q_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
102	      I40E_TXD_FLTR_QW0_QINDEX_MASK;
103
104	fpt |= (fdir_data->flex_off << I40E_TXD_FLTR_QW0_FLEXOFF_SHIFT) &
105	       I40E_TXD_FLTR_QW0_FLEXOFF_MASK;
106
107	fpt |= (fdir_data->pctype << I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) &
108	       I40E_TXD_FLTR_QW0_PCTYPE_MASK;
109
110	/* Use LAN VSI Id if not programmed by user */
111	if (fdir_data->dest_vsi == 0)
112		fpt |= (pf->vsi[pf->lan_vsi]->id) <<
113		       I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
114	else
115		fpt |= ((u32)fdir_data->dest_vsi <<
116			I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT) &
117		       I40E_TXD_FLTR_QW0_DEST_VSI_MASK;
118
119	dcc = I40E_TX_DESC_DTYPE_FILTER_PROG;
120
121	if (add)
122		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
123		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
124	else
125		dcc |= I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
126		       I40E_TXD_FLTR_QW1_PCMD_SHIFT;
127
128	dcc |= (fdir_data->dest_ctl << I40E_TXD_FLTR_QW1_DEST_SHIFT) &
129	       I40E_TXD_FLTR_QW1_DEST_MASK;
130
131	dcc |= (fdir_data->fd_status << I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT) &
132	       I40E_TXD_FLTR_QW1_FD_STATUS_MASK;
133
134	if (fdir_data->cnt_index != 0) {
135		dcc |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
136		dcc |= ((u32)fdir_data->cnt_index <<
137			I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
138			I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
139	}
140
141	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(fpt);
142	fdir_desc->rsvd = cpu_to_le32(0);
143	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dcc);
144	fdir_desc->fd_id = cpu_to_le32(fdir_data->fd_id);
145
146	/* Now program a dummy descriptor */
147	i = tx_ring->next_to_use;
148	tx_desc = I40E_TX_DESC(tx_ring, i);
149	tx_buf = &tx_ring->tx_bi[i];
150
151	tx_ring->next_to_use = ((i + 1) < tx_ring->count) ? i + 1 : 0;
152
153	memset(tx_buf, 0, sizeof(struct i40e_tx_buffer));
154
155	/* record length, and DMA address */
156	dma_unmap_len_set(tx_buf, len, I40E_FDIR_MAX_RAW_PACKET_SIZE);
157	dma_unmap_addr_set(tx_buf, dma, dma);
158
159	tx_desc->buffer_addr = cpu_to_le64(dma);
160	td_cmd = I40E_TXD_CMD | I40E_TX_DESC_CMD_DUMMY;
161
162	tx_buf->tx_flags = I40E_TX_FLAGS_FD_SB;
163	tx_buf->raw_buf = (void *)raw_packet;
164
165	tx_desc->cmd_type_offset_bsz =
166		build_ctob(td_cmd, 0, I40E_FDIR_MAX_RAW_PACKET_SIZE, 0);
167
168	/* set the timestamp */
169	tx_buf->time_stamp = jiffies;
170
171	/* Force memory writes to complete before letting h/w
172	 * know there are new descriptors to fetch.
173	 */
174	wmb();
175
176	/* Mark the data descriptor to be watched */
177	first->next_to_watch = tx_desc;
178
179	writel(tx_ring->next_to_use, tx_ring->tail);
180	return 0;
181
182dma_fail:
183	return -1;
184}
185
186#define IP_HEADER_OFFSET 14
187#define I40E_UDPIP_DUMMY_PACKET_LEN 42
188/**
189 * i40e_add_del_fdir_udpv4 - Add/Remove UDPv4 filters
190 * @vsi: pointer to the targeted VSI
191 * @fd_data: the flow director data required for the FDir descriptor
192 * @add: true adds a filter, false removes it
193 *
194 * Returns 0 if the filters were successfully added or removed
195 **/
196static int i40e_add_del_fdir_udpv4(struct i40e_vsi *vsi,
197				   struct i40e_fdir_filter *fd_data,
198				   bool add)
199{
200	struct i40e_pf *pf = vsi->back;
201	struct udphdr *udp;
202	struct iphdr *ip;
203	bool err = false;
204	u8 *raw_packet;
205	int ret;
206	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
207		0x45, 0, 0, 0x1c, 0, 0, 0x40, 0, 0x40, 0x11, 0, 0, 0, 0, 0, 0,
208		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
209
210	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
211	if (!raw_packet)
212		return -ENOMEM;
213	memcpy(raw_packet, packet, I40E_UDPIP_DUMMY_PACKET_LEN);
214
215	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
216	udp = (struct udphdr *)(raw_packet + IP_HEADER_OFFSET
217	      + sizeof(struct iphdr));
218
219	ip->daddr = fd_data->dst_ip[0];
220	udp->dest = fd_data->dst_port;
221	ip->saddr = fd_data->src_ip[0];
222	udp->source = fd_data->src_port;
223
224	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_UDP;
225	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
226	if (ret) {
227		dev_info(&pf->pdev->dev,
228			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
229			 fd_data->pctype, fd_data->fd_id, ret);
230		err = true;
231	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
232		if (add)
233			dev_info(&pf->pdev->dev,
234				 "Filter OK for PCTYPE %d loc = %d\n",
235				 fd_data->pctype, fd_data->fd_id);
236		else
237			dev_info(&pf->pdev->dev,
238				 "Filter deleted for PCTYPE %d loc = %d\n",
239				 fd_data->pctype, fd_data->fd_id);
240	}
241	return err ? -EOPNOTSUPP : 0;
242}
243
244#define I40E_TCPIP_DUMMY_PACKET_LEN 54
245/**
246 * i40e_add_del_fdir_tcpv4 - Add/Remove TCPv4 filters
247 * @vsi: pointer to the targeted VSI
248 * @fd_data: the flow director data required for the FDir descriptor
249 * @add: true adds a filter, false removes it
250 *
251 * Returns 0 if the filters were successfully added or removed
252 **/
253static int i40e_add_del_fdir_tcpv4(struct i40e_vsi *vsi,
254				   struct i40e_fdir_filter *fd_data,
255				   bool add)
256{
257	struct i40e_pf *pf = vsi->back;
258	struct tcphdr *tcp;
259	struct iphdr *ip;
260	bool err = false;
261	u8 *raw_packet;
262	int ret;
263	/* Dummy packet */
264	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
265		0x45, 0, 0, 0x28, 0, 0, 0x40, 0, 0x40, 0x6, 0, 0, 0, 0, 0, 0,
266		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x80, 0x11,
267		0x0, 0x72, 0, 0, 0, 0};
268
269	raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
270	if (!raw_packet)
271		return -ENOMEM;
272	memcpy(raw_packet, packet, I40E_TCPIP_DUMMY_PACKET_LEN);
273
274	ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
275	tcp = (struct tcphdr *)(raw_packet + IP_HEADER_OFFSET
276	      + sizeof(struct iphdr));
277
278	ip->daddr = fd_data->dst_ip[0];
279	tcp->dest = fd_data->dst_port;
280	ip->saddr = fd_data->src_ip[0];
281	tcp->source = fd_data->src_port;
282
283	if (add) {
284		pf->fd_tcp_rule++;
285		if (pf->flags & I40E_FLAG_FD_ATR_ENABLED) {
286			dev_info(&pf->pdev->dev, "Forcing ATR off, sideband rules for TCP/IPv4 flow being applied\n");
287			pf->flags &= ~I40E_FLAG_FD_ATR_ENABLED;
288		}
289	} else {
290		pf->fd_tcp_rule = (pf->fd_tcp_rule > 0) ?
291				  (pf->fd_tcp_rule - 1) : 0;
292		if (pf->fd_tcp_rule == 0) {
293			pf->flags |= I40E_FLAG_FD_ATR_ENABLED;
294			dev_info(&pf->pdev->dev, "ATR re-enabled due to no sideband TCP/IPv4 rules\n");
295		}
296	}
297
298	fd_data->pctype = I40E_FILTER_PCTYPE_NONF_IPV4_TCP;
299	ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
300
301	if (ret) {
302		dev_info(&pf->pdev->dev,
303			 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
304			 fd_data->pctype, fd_data->fd_id, ret);
305		err = true;
306	} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
307		if (add)
308			dev_info(&pf->pdev->dev, "Filter OK for PCTYPE %d loc = %d)\n",
309				 fd_data->pctype, fd_data->fd_id);
310		else
311			dev_info(&pf->pdev->dev,
312				 "Filter deleted for PCTYPE %d loc = %d\n",
313				 fd_data->pctype, fd_data->fd_id);
314	}
315
316	return err ? -EOPNOTSUPP : 0;
317}
318
319/**
320 * i40e_add_del_fdir_sctpv4 - Add/Remove SCTPv4 Flow Director filters for
321 * a specific flow spec
322 * @vsi: pointer to the targeted VSI
323 * @fd_data: the flow director data required for the FDir descriptor
324 * @add: true adds a filter, false removes it
325 *
326 * Always returns -EOPNOTSUPP
327 **/
328static int i40e_add_del_fdir_sctpv4(struct i40e_vsi *vsi,
329				    struct i40e_fdir_filter *fd_data,
330				    bool add)
331{
332	return -EOPNOTSUPP;
333}
334
335#define I40E_IP_DUMMY_PACKET_LEN 34
336/**
337 * i40e_add_del_fdir_ipv4 - Add/Remove IPv4 Flow Director filters for
338 * a specific flow spec
339 * @vsi: pointer to the targeted VSI
340 * @fd_data: the flow director data required for the FDir descriptor
341 * @add: true adds a filter, false removes it
342 *
343 * Returns 0 if the filters were successfully added or removed
344 **/
345static int i40e_add_del_fdir_ipv4(struct i40e_vsi *vsi,
346				  struct i40e_fdir_filter *fd_data,
347				  bool add)
348{
349	struct i40e_pf *pf = vsi->back;
350	struct iphdr *ip;
351	bool err = false;
352	u8 *raw_packet;
353	int ret;
354	int i;
355	static char packet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x08, 0,
356		0x45, 0, 0, 0x14, 0, 0, 0x40, 0, 0x40, 0x10, 0, 0, 0, 0, 0, 0,
357		0, 0, 0, 0};
358
359	for (i = I40E_FILTER_PCTYPE_NONF_IPV4_OTHER;
360	     i <= I40E_FILTER_PCTYPE_FRAG_IPV4;	i++) {
361		raw_packet = kzalloc(I40E_FDIR_MAX_RAW_PACKET_SIZE, GFP_KERNEL);
362		if (!raw_packet)
363			return -ENOMEM;
364		memcpy(raw_packet, packet, I40E_IP_DUMMY_PACKET_LEN);
365		ip = (struct iphdr *)(raw_packet + IP_HEADER_OFFSET);
366
367		ip->saddr = fd_data->src_ip[0];
368		ip->daddr = fd_data->dst_ip[0];
369		ip->protocol = 0;
370
371		fd_data->pctype = i;
372		ret = i40e_program_fdir_filter(fd_data, raw_packet, pf, add);
373
374		if (ret) {
375			dev_info(&pf->pdev->dev,
376				 "PCTYPE:%d, Filter command send failed for fd_id:%d (ret = %d)\n",
377				 fd_data->pctype, fd_data->fd_id, ret);
378			err = true;
379		} else if (I40E_DEBUG_FD & pf->hw.debug_mask) {
380			if (add)
381				dev_info(&pf->pdev->dev,
382					 "Filter OK for PCTYPE %d loc = %d\n",
383					 fd_data->pctype, fd_data->fd_id);
384			else
385				dev_info(&pf->pdev->dev,
386					 "Filter deleted for PCTYPE %d loc = %d\n",
387					 fd_data->pctype, fd_data->fd_id);
388		}
389	}
390
391	return err ? -EOPNOTSUPP : 0;
392}
393
394/**
395 * i40e_add_del_fdir - Build raw packets to add/del fdir filter
396 * @vsi: pointer to the targeted VSI
397 * @cmd: command to get or set RX flow classification rules
398 * @add: true adds a filter, false removes it
399 *
400 **/
401int i40e_add_del_fdir(struct i40e_vsi *vsi,
402		      struct i40e_fdir_filter *input, bool add)
403{
404	struct i40e_pf *pf = vsi->back;
405	int ret;
406
407	switch (input->flow_type & ~FLOW_EXT) {
408	case TCP_V4_FLOW:
409		ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
410		break;
411	case UDP_V4_FLOW:
412		ret = i40e_add_del_fdir_udpv4(vsi, input, add);
413		break;
414	case SCTP_V4_FLOW:
415		ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
416		break;
417	case IPV4_FLOW:
418		ret = i40e_add_del_fdir_ipv4(vsi, input, add);
419		break;
420	case IP_USER_FLOW:
421		switch (input->ip4_proto) {
422		case IPPROTO_TCP:
423			ret = i40e_add_del_fdir_tcpv4(vsi, input, add);
424			break;
425		case IPPROTO_UDP:
426			ret = i40e_add_del_fdir_udpv4(vsi, input, add);
427			break;
428		case IPPROTO_SCTP:
429			ret = i40e_add_del_fdir_sctpv4(vsi, input, add);
430			break;
431		default:
432			ret = i40e_add_del_fdir_ipv4(vsi, input, add);
433			break;
434		}
435		break;
436	default:
437		dev_info(&pf->pdev->dev, "Could not specify spec type %d\n",
438			 input->flow_type);
439		ret = -EINVAL;
440	}
441
442	/* The buffer allocated here is freed by the i40e_clean_tx_ring() */
443	return ret;
444}
445
446/**
447 * i40e_fd_handle_status - check the Programming Status for FD
448 * @rx_ring: the Rx ring for this descriptor
449 * @rx_desc: the Rx descriptor for programming Status, not a packet descriptor.
450 * @prog_id: the id originally used for programming
451 *
452 * This is used to verify if the FD programming or invalidation
453 * requested by SW to the HW is successful or not and take actions accordingly.
454 **/
455static void i40e_fd_handle_status(struct i40e_ring *rx_ring,
456				  union i40e_rx_desc *rx_desc, u8 prog_id)
457{
458	struct i40e_pf *pf = rx_ring->vsi->back;
459	struct pci_dev *pdev = pf->pdev;
460	u32 fcnt_prog, fcnt_avail;
461	u32 error;
462	u64 qw;
463
464	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
465	error = (qw & I40E_RX_PROG_STATUS_DESC_QW1_ERROR_MASK) >>
466		I40E_RX_PROG_STATUS_DESC_QW1_ERROR_SHIFT;
467
468	if (error == (0x1 << I40E_RX_PROG_STATUS_DESC_FD_TBL_FULL_SHIFT)) {
469		if ((rx_desc->wb.qword0.hi_dword.fd_id != 0) ||
470		    (I40E_DEBUG_FD & pf->hw.debug_mask))
471			dev_warn(&pdev->dev, "ntuple filter loc = %d, could not be added\n",
472				 rx_desc->wb.qword0.hi_dword.fd_id);
473
474		/* Check if the programming error is for ATR.
475		 * If so, auto disable ATR and set a state for
476		 * flush in progress. Next time we come here if flush is in
477		 * progress do nothing, once flush is complete the state will
478		 * be cleared.
479		 */
480		if (test_bit(__I40E_FD_FLUSH_REQUESTED, &pf->state))
481			return;
482
483		pf->fd_add_err++;
484		/* store the current atr filter count */
485		pf->fd_atr_cnt = i40e_get_current_atr_cnt(pf);
486
487		if ((rx_desc->wb.qword0.hi_dword.fd_id == 0) &&
488		    (pf->auto_disable_flags & I40E_FLAG_FD_SB_ENABLED)) {
489			pf->auto_disable_flags |= I40E_FLAG_FD_ATR_ENABLED;
490			set_bit(__I40E_FD_FLUSH_REQUESTED, &pf->state);
491		}
492
493		/* filter programming failed most likely due to table full */
494		fcnt_prog = i40e_get_global_fd_count(pf);
495		fcnt_avail = pf->fdir_pf_filter_count;
496		/* If ATR is running fcnt_prog can quickly change,
497		 * if we are very close to full, it makes sense to disable
498		 * FD ATR/SB and then re-enable it when there is room.
499		 */
500		if (fcnt_prog >= (fcnt_avail - I40E_FDIR_BUFFER_FULL_MARGIN)) {
501			if ((pf->flags & I40E_FLAG_FD_SB_ENABLED) &&
502			    !(pf->auto_disable_flags &
503				     I40E_FLAG_FD_SB_ENABLED)) {
504				dev_warn(&pdev->dev, "FD filter space full, new ntuple rules will not be added\n");
505				pf->auto_disable_flags |=
506							I40E_FLAG_FD_SB_ENABLED;
507			}
508		} else {
509			dev_info(&pdev->dev,
510				"FD filter programming failed due to incorrect filter parameters\n");
511		}
512	} else if (error ==
513			  (0x1 << I40E_RX_PROG_STATUS_DESC_NO_FD_ENTRY_SHIFT)) {
514		if (I40E_DEBUG_FD & pf->hw.debug_mask)
515			dev_info(&pdev->dev, "ntuple filter fd_id = %d, could not be removed\n",
516				 rx_desc->wb.qword0.hi_dword.fd_id);
517	}
518}
519
520/**
521 * i40e_unmap_and_free_tx_resource - Release a Tx buffer
522 * @ring:      the ring that owns the buffer
523 * @tx_buffer: the buffer to free
524 **/
525static void i40e_unmap_and_free_tx_resource(struct i40e_ring *ring,
526					    struct i40e_tx_buffer *tx_buffer)
527{
528	if (tx_buffer->skb) {
529		if (tx_buffer->tx_flags & I40E_TX_FLAGS_FD_SB)
530			kfree(tx_buffer->raw_buf);
531		else
532			dev_kfree_skb_any(tx_buffer->skb);
533
534		if (dma_unmap_len(tx_buffer, len))
535			dma_unmap_single(ring->dev,
536					 dma_unmap_addr(tx_buffer, dma),
537					 dma_unmap_len(tx_buffer, len),
538					 DMA_TO_DEVICE);
539	} else if (dma_unmap_len(tx_buffer, len)) {
540		dma_unmap_page(ring->dev,
541			       dma_unmap_addr(tx_buffer, dma),
542			       dma_unmap_len(tx_buffer, len),
543			       DMA_TO_DEVICE);
544	}
545	tx_buffer->next_to_watch = NULL;
546	tx_buffer->skb = NULL;
547	dma_unmap_len_set(tx_buffer, len, 0);
548	/* tx_buffer must be completely set up in the transmit path */
549}
550
551/**
552 * i40e_clean_tx_ring - Free any empty Tx buffers
553 * @tx_ring: ring to be cleaned
554 **/
555void i40e_clean_tx_ring(struct i40e_ring *tx_ring)
556{
557	unsigned long bi_size;
558	u16 i;
559
560	/* ring already cleared, nothing to do */
561	if (!tx_ring->tx_bi)
562		return;
563
564	/* Free all the Tx ring sk_buffs */
565	for (i = 0; i < tx_ring->count; i++)
566		i40e_unmap_and_free_tx_resource(tx_ring, &tx_ring->tx_bi[i]);
567
568	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
569	memset(tx_ring->tx_bi, 0, bi_size);
570
571	/* Zero out the descriptor ring */
572	memset(tx_ring->desc, 0, tx_ring->size);
573
574	tx_ring->next_to_use = 0;
575	tx_ring->next_to_clean = 0;
576
577	if (!tx_ring->netdev)
578		return;
579
580	/* cleanup Tx queue statistics */
581	netdev_tx_reset_queue(netdev_get_tx_queue(tx_ring->netdev,
582						  tx_ring->queue_index));
583}
584
585/**
586 * i40e_free_tx_resources - Free Tx resources per queue
587 * @tx_ring: Tx descriptor ring for a specific queue
588 *
589 * Free all transmit software resources
590 **/
591void i40e_free_tx_resources(struct i40e_ring *tx_ring)
592{
593	i40e_clean_tx_ring(tx_ring);
594	kfree(tx_ring->tx_bi);
595	tx_ring->tx_bi = NULL;
596
597	if (tx_ring->desc) {
598		dma_free_coherent(tx_ring->dev, tx_ring->size,
599				  tx_ring->desc, tx_ring->dma);
600		tx_ring->desc = NULL;
601	}
602}
603
604/**
605 * i40e_get_head - Retrieve head from head writeback
606 * @tx_ring:  tx ring to fetch head of
607 *
608 * Returns value of Tx ring head based on value stored
609 * in head write-back location
610 **/
611static inline u32 i40e_get_head(struct i40e_ring *tx_ring)
612{
613	void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count;
614
615	return le32_to_cpu(*(volatile __le32 *)head);
616}
617
618/**
619 * i40e_get_tx_pending - how many tx descriptors not processed
620 * @tx_ring: the ring of descriptors
621 *
622 * Since there is no access to the ring head register
623 * in XL710, we need to use our local copies
624 **/
625static u32 i40e_get_tx_pending(struct i40e_ring *ring)
626{
627	u32 head, tail;
628
629	head = i40e_get_head(ring);
630	tail = readl(ring->tail);
631
632	if (head != tail)
633		return (head < tail) ?
634			tail - head : (tail + ring->count - head);
635
636	return 0;
637}
638
639/**
640 * i40e_check_tx_hang - Is there a hang in the Tx queue
641 * @tx_ring: the ring of descriptors
642 **/
643static bool i40e_check_tx_hang(struct i40e_ring *tx_ring)
644{
645	u32 tx_done = tx_ring->stats.packets;
646	u32 tx_done_old = tx_ring->tx_stats.tx_done_old;
647	u32 tx_pending = i40e_get_tx_pending(tx_ring);
648	struct i40e_pf *pf = tx_ring->vsi->back;
649	bool ret = false;
650
651	clear_check_for_tx_hang(tx_ring);
652
653	/* Check for a hung queue, but be thorough. This verifies
654	 * that a transmit has been completed since the previous
655	 * check AND there is at least one packet pending. The
656	 * ARMED bit is set to indicate a potential hang. The
657	 * bit is cleared if a pause frame is received to remove
658	 * false hang detection due to PFC or 802.3x frames. By
659	 * requiring this to fail twice we avoid races with
660	 * PFC clearing the ARMED bit and conditions where we
661	 * run the check_tx_hang logic with a transmit completion
662	 * pending but without time to complete it yet.
663	 */
664	if ((tx_done_old == tx_done) && tx_pending) {
665		/* make sure it is true for two checks in a row */
666		ret = test_and_set_bit(__I40E_HANG_CHECK_ARMED,
667				       &tx_ring->state);
668	} else if (tx_done_old == tx_done &&
669		   (tx_pending < I40E_MIN_DESC_PENDING) && (tx_pending > 0)) {
670		if (I40E_DEBUG_FLOW & pf->hw.debug_mask)
671			dev_info(tx_ring->dev, "HW needs some more descs to do a cacheline flush. tx_pending %d, queue %d",
672				 tx_pending, tx_ring->queue_index);
673		pf->tx_sluggish_count++;
674	} else {
675		/* update completed stats and disarm the hang check */
676		tx_ring->tx_stats.tx_done_old = tx_done;
677		clear_bit(__I40E_HANG_CHECK_ARMED, &tx_ring->state);
678	}
679
680	return ret;
681}
682
683#define WB_STRIDE 0x3
684
685/**
686 * i40e_clean_tx_irq - Reclaim resources after transmit completes
687 * @tx_ring:  tx ring to clean
688 * @budget:   how many cleans we're allowed
689 *
690 * Returns true if there's any budget left (e.g. the clean is finished)
691 **/
692static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
693{
694	u16 i = tx_ring->next_to_clean;
695	struct i40e_tx_buffer *tx_buf;
696	struct i40e_tx_desc *tx_head;
697	struct i40e_tx_desc *tx_desc;
698	unsigned int total_packets = 0;
699	unsigned int total_bytes = 0;
700
701	tx_buf = &tx_ring->tx_bi[i];
702	tx_desc = I40E_TX_DESC(tx_ring, i);
703	i -= tx_ring->count;
704
705	tx_head = I40E_TX_DESC(tx_ring, i40e_get_head(tx_ring));
706
707	do {
708		struct i40e_tx_desc *eop_desc = tx_buf->next_to_watch;
709
710		/* if next_to_watch is not set then there is no work pending */
711		if (!eop_desc)
712			break;
713
714		/* prevent any other reads prior to eop_desc */
715		read_barrier_depends();
716
717		/* we have caught up to head, no work left to do */
718		if (tx_head == tx_desc)
719			break;
720
721		/* clear next_to_watch to prevent false hangs */
722		tx_buf->next_to_watch = NULL;
723
724		/* update the statistics for this packet */
725		total_bytes += tx_buf->bytecount;
726		total_packets += tx_buf->gso_segs;
727
728		/* free the skb */
729		dev_consume_skb_any(tx_buf->skb);
730
731		/* unmap skb header data */
732		dma_unmap_single(tx_ring->dev,
733				 dma_unmap_addr(tx_buf, dma),
734				 dma_unmap_len(tx_buf, len),
735				 DMA_TO_DEVICE);
736
737		/* clear tx_buffer data */
738		tx_buf->skb = NULL;
739		dma_unmap_len_set(tx_buf, len, 0);
740
741		/* unmap remaining buffers */
742		while (tx_desc != eop_desc) {
743
744			tx_buf++;
745			tx_desc++;
746			i++;
747			if (unlikely(!i)) {
748				i -= tx_ring->count;
749				tx_buf = tx_ring->tx_bi;
750				tx_desc = I40E_TX_DESC(tx_ring, 0);
751			}
752
753			/* unmap any remaining paged data */
754			if (dma_unmap_len(tx_buf, len)) {
755				dma_unmap_page(tx_ring->dev,
756					       dma_unmap_addr(tx_buf, dma),
757					       dma_unmap_len(tx_buf, len),
758					       DMA_TO_DEVICE);
759				dma_unmap_len_set(tx_buf, len, 0);
760			}
761		}
762
763		/* move us one more past the eop_desc for start of next pkt */
764		tx_buf++;
765		tx_desc++;
766		i++;
767		if (unlikely(!i)) {
768			i -= tx_ring->count;
769			tx_buf = tx_ring->tx_bi;
770			tx_desc = I40E_TX_DESC(tx_ring, 0);
771		}
772
773		prefetch(tx_desc);
774
775		/* update budget accounting */
776		budget--;
777	} while (likely(budget));
778
779	i += tx_ring->count;
780	tx_ring->next_to_clean = i;
781	u64_stats_update_begin(&tx_ring->syncp);
782	tx_ring->stats.bytes += total_bytes;
783	tx_ring->stats.packets += total_packets;
784	u64_stats_update_end(&tx_ring->syncp);
785	tx_ring->q_vector->tx.total_bytes += total_bytes;
786	tx_ring->q_vector->tx.total_packets += total_packets;
787
788	/* check to see if there are any non-cache aligned descriptors
789	 * waiting to be written back, and kick the hardware to force
790	 * them to be written back in case of napi polling
791	 */
792	if (budget &&
793	    !((i & WB_STRIDE) == WB_STRIDE) &&
794	    !test_bit(__I40E_DOWN, &tx_ring->vsi->state) &&
795	    (I40E_DESC_UNUSED(tx_ring) != tx_ring->count))
796		tx_ring->arm_wb = true;
797	else
798		tx_ring->arm_wb = false;
799
800	if (check_for_tx_hang(tx_ring) && i40e_check_tx_hang(tx_ring)) {
801		/* schedule immediate reset if we believe we hung */
802		dev_info(tx_ring->dev, "Detected Tx Unit Hang\n"
803			 "  VSI                  <%d>\n"
804			 "  Tx Queue             <%d>\n"
805			 "  next_to_use          <%x>\n"
806			 "  next_to_clean        <%x>\n",
807			 tx_ring->vsi->seid,
808			 tx_ring->queue_index,
809			 tx_ring->next_to_use, i);
810		dev_info(tx_ring->dev, "tx_bi[next_to_clean]\n"
811			 "  time_stamp           <%lx>\n"
812			 "  jiffies              <%lx>\n",
813			 tx_ring->tx_bi[i].time_stamp, jiffies);
814
815		netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
816
817		dev_info(tx_ring->dev,
818			 "tx hang detected on queue %d, reset requested\n",
819			 tx_ring->queue_index);
820
821		/* do not fire the reset immediately, wait for the stack to
822		 * decide we are truly stuck, also prevents every queue from
823		 * simultaneously requesting a reset
824		 */
825
826		/* the adapter is about to reset, no point in enabling polling */
827		budget = 1;
828	}
829
830	netdev_tx_completed_queue(netdev_get_tx_queue(tx_ring->netdev,
831						      tx_ring->queue_index),
832				  total_packets, total_bytes);
833
834#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
835	if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
836		     (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
837		/* Make sure that anybody stopping the queue after this
838		 * sees the new next_to_clean.
839		 */
840		smp_mb();
841		if (__netif_subqueue_stopped(tx_ring->netdev,
842					     tx_ring->queue_index) &&
843		   !test_bit(__I40E_DOWN, &tx_ring->vsi->state)) {
844			netif_wake_subqueue(tx_ring->netdev,
845					    tx_ring->queue_index);
846			++tx_ring->tx_stats.restart_queue;
847		}
848	}
849
850	return !!budget;
851}
852
853/**
854 * i40e_force_wb - Arm hardware to do a wb on noncache aligned descriptors
855 * @vsi: the VSI we care about
856 * @q_vector: the vector  on which to force writeback
857 *
858 **/
859static void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector)
860{
861	u32 val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
862		  I40E_PFINT_DYN_CTLN_ITR_INDX_MASK | /* set noitr */
863		  I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
864		  I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK;
865		  /* allow 00 to be written to the index */
866
867	wr32(&vsi->back->hw,
868	     I40E_PFINT_DYN_CTLN(q_vector->v_idx + vsi->base_vector - 1),
869	     val);
870}
871
872/**
873 * i40e_set_new_dynamic_itr - Find new ITR level
874 * @rc: structure containing ring performance data
875 *
876 * Stores a new ITR value based on packets and byte counts during
877 * the last interrupt.  The advantage of per interrupt computation
878 * is faster updates and more accurate ITR for the current traffic
879 * pattern.  Constants in this function were computed based on
880 * theoretical maximum wire speed and thresholds were set based on
881 * testing data as well as attempting to minimize response time
882 * while increasing bulk throughput.
883 **/
884static void i40e_set_new_dynamic_itr(struct i40e_ring_container *rc)
885{
886	enum i40e_latency_range new_latency_range = rc->latency_range;
887	u32 new_itr = rc->itr;
888	int bytes_per_int;
889
890	if (rc->total_packets == 0 || !rc->itr)
891		return;
892
893	/* simple throttlerate management
894	 *   0-10MB/s   lowest (100000 ints/s)
895	 *  10-20MB/s   low    (20000 ints/s)
896	 *  20-1249MB/s bulk   (8000 ints/s)
897	 */
898	bytes_per_int = rc->total_bytes / rc->itr;
899	switch (rc->itr) {
900	case I40E_LOWEST_LATENCY:
901		if (bytes_per_int > 10)
902			new_latency_range = I40E_LOW_LATENCY;
903		break;
904	case I40E_LOW_LATENCY:
905		if (bytes_per_int > 20)
906			new_latency_range = I40E_BULK_LATENCY;
907		else if (bytes_per_int <= 10)
908			new_latency_range = I40E_LOWEST_LATENCY;
909		break;
910	case I40E_BULK_LATENCY:
911		if (bytes_per_int <= 20)
912			rc->latency_range = I40E_LOW_LATENCY;
913		break;
914	}
915
916	switch (new_latency_range) {
917	case I40E_LOWEST_LATENCY:
918		new_itr = I40E_ITR_100K;
919		break;
920	case I40E_LOW_LATENCY:
921		new_itr = I40E_ITR_20K;
922		break;
923	case I40E_BULK_LATENCY:
924		new_itr = I40E_ITR_8K;
925		break;
926	default:
927		break;
928	}
929
930	if (new_itr != rc->itr) {
931		/* do an exponential smoothing */
932		new_itr = (10 * new_itr * rc->itr) /
933			  ((9 * new_itr) + rc->itr);
934		rc->itr = new_itr & I40E_MAX_ITR;
935	}
936
937	rc->total_bytes = 0;
938	rc->total_packets = 0;
939}
940
941/**
942 * i40e_update_dynamic_itr - Adjust ITR based on bytes per int
943 * @q_vector: the vector to adjust
944 **/
945static void i40e_update_dynamic_itr(struct i40e_q_vector *q_vector)
946{
947	u16 vector = q_vector->vsi->base_vector + q_vector->v_idx;
948	struct i40e_hw *hw = &q_vector->vsi->back->hw;
949	u32 reg_addr;
950	u16 old_itr;
951
952	reg_addr = I40E_PFINT_ITRN(I40E_RX_ITR, vector - 1);
953	old_itr = q_vector->rx.itr;
954	i40e_set_new_dynamic_itr(&q_vector->rx);
955	if (old_itr != q_vector->rx.itr)
956		wr32(hw, reg_addr, q_vector->rx.itr);
957
958	reg_addr = I40E_PFINT_ITRN(I40E_TX_ITR, vector - 1);
959	old_itr = q_vector->tx.itr;
960	i40e_set_new_dynamic_itr(&q_vector->tx);
961	if (old_itr != q_vector->tx.itr)
962		wr32(hw, reg_addr, q_vector->tx.itr);
963}
964
965/**
966 * i40e_clean_programming_status - clean the programming status descriptor
967 * @rx_ring: the rx ring that has this descriptor
968 * @rx_desc: the rx descriptor written back by HW
969 *
970 * Flow director should handle FD_FILTER_STATUS to check its filter programming
971 * status being successful or not and take actions accordingly. FCoE should
972 * handle its context/filter programming/invalidation status and take actions.
973 *
974 **/
975static void i40e_clean_programming_status(struct i40e_ring *rx_ring,
976					  union i40e_rx_desc *rx_desc)
977{
978	u64 qw;
979	u8 id;
980
981	qw = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
982	id = (qw & I40E_RX_PROG_STATUS_DESC_QW1_PROGID_MASK) >>
983		  I40E_RX_PROG_STATUS_DESC_QW1_PROGID_SHIFT;
984
985	if (id == I40E_RX_PROG_STATUS_DESC_FD_FILTER_STATUS)
986		i40e_fd_handle_status(rx_ring, rx_desc, id);
987#ifdef I40E_FCOE
988	else if ((id == I40E_RX_PROG_STATUS_DESC_FCOE_CTXT_PROG_STATUS) ||
989		 (id == I40E_RX_PROG_STATUS_DESC_FCOE_CTXT_INVL_STATUS))
990		i40e_fcoe_handle_status(rx_ring, rx_desc, id);
991#endif
992}
993
994/**
995 * i40e_setup_tx_descriptors - Allocate the Tx descriptors
996 * @tx_ring: the tx ring to set up
997 *
998 * Return 0 on success, negative on error
999 **/
1000int i40e_setup_tx_descriptors(struct i40e_ring *tx_ring)
1001{
1002	struct device *dev = tx_ring->dev;
1003	int bi_size;
1004
1005	if (!dev)
1006		return -ENOMEM;
1007
1008	bi_size = sizeof(struct i40e_tx_buffer) * tx_ring->count;
1009	tx_ring->tx_bi = kzalloc(bi_size, GFP_KERNEL);
1010	if (!tx_ring->tx_bi)
1011		goto err;
1012
1013	/* round up to nearest 4K */
1014	tx_ring->size = tx_ring->count * sizeof(struct i40e_tx_desc);
1015	/* add u32 for head writeback, align after this takes care of
1016	 * guaranteeing this is at least one cache line in size
1017	 */
1018	tx_ring->size += sizeof(u32);
1019	tx_ring->size = ALIGN(tx_ring->size, 4096);
1020	tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
1021					   &tx_ring->dma, GFP_KERNEL);
1022	if (!tx_ring->desc) {
1023		dev_info(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
1024			 tx_ring->size);
1025		goto err;
1026	}
1027
1028	tx_ring->next_to_use = 0;
1029	tx_ring->next_to_clean = 0;
1030	return 0;
1031
1032err:
1033	kfree(tx_ring->tx_bi);
1034	tx_ring->tx_bi = NULL;
1035	return -ENOMEM;
1036}
1037
1038/**
1039 * i40e_clean_rx_ring - Free Rx buffers
1040 * @rx_ring: ring to be cleaned
1041 **/
1042void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
1043{
1044	struct device *dev = rx_ring->dev;
1045	struct i40e_rx_buffer *rx_bi;
1046	unsigned long bi_size;
1047	u16 i;
1048
1049	/* ring already cleared, nothing to do */
1050	if (!rx_ring->rx_bi)
1051		return;
1052
1053	if (ring_is_ps_enabled(rx_ring)) {
1054		int bufsz = ALIGN(rx_ring->rx_hdr_len, 256) * rx_ring->count;
1055
1056		rx_bi = &rx_ring->rx_bi[0];
1057		if (rx_bi->hdr_buf) {
1058			dma_free_coherent(dev,
1059					  bufsz,
1060					  rx_bi->hdr_buf,
1061					  rx_bi->dma);
1062			for (i = 0; i < rx_ring->count; i++) {
1063				rx_bi = &rx_ring->rx_bi[i];
1064				rx_bi->dma = 0;
1065				rx_bi->hdr_buf = NULL;
1066			}
1067		}
1068	}
1069	/* Free all the Rx ring sk_buffs */
1070	for (i = 0; i < rx_ring->count; i++) {
1071		rx_bi = &rx_ring->rx_bi[i];
1072		if (rx_bi->dma) {
1073			dma_unmap_single(dev,
1074					 rx_bi->dma,
1075					 rx_ring->rx_buf_len,
1076					 DMA_FROM_DEVICE);
1077			rx_bi->dma = 0;
1078		}
1079		if (rx_bi->skb) {
1080			dev_kfree_skb(rx_bi->skb);
1081			rx_bi->skb = NULL;
1082		}
1083		if (rx_bi->page) {
1084			if (rx_bi->page_dma) {
1085				dma_unmap_page(dev,
1086					       rx_bi->page_dma,
1087					       PAGE_SIZE / 2,
1088					       DMA_FROM_DEVICE);
1089				rx_bi->page_dma = 0;
1090			}
1091			__free_page(rx_bi->page);
1092			rx_bi->page = NULL;
1093			rx_bi->page_offset = 0;
1094		}
1095	}
1096
1097	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1098	memset(rx_ring->rx_bi, 0, bi_size);
1099
1100	/* Zero out the descriptor ring */
1101	memset(rx_ring->desc, 0, rx_ring->size);
1102
1103	rx_ring->next_to_clean = 0;
1104	rx_ring->next_to_use = 0;
1105}
1106
1107/**
1108 * i40e_free_rx_resources - Free Rx resources
1109 * @rx_ring: ring to clean the resources from
1110 *
1111 * Free all receive software resources
1112 **/
1113void i40e_free_rx_resources(struct i40e_ring *rx_ring)
1114{
1115	i40e_clean_rx_ring(rx_ring);
1116	kfree(rx_ring->rx_bi);
1117	rx_ring->rx_bi = NULL;
1118
1119	if (rx_ring->desc) {
1120		dma_free_coherent(rx_ring->dev, rx_ring->size,
1121				  rx_ring->desc, rx_ring->dma);
1122		rx_ring->desc = NULL;
1123	}
1124}
1125
1126/**
1127 * i40e_alloc_rx_headers - allocate rx header buffers
1128 * @rx_ring: ring to alloc buffers
1129 *
1130 * Allocate rx header buffers for the entire ring. As these are static,
1131 * this is only called when setting up a new ring.
1132 **/
1133void i40e_alloc_rx_headers(struct i40e_ring *rx_ring)
1134{
1135	struct device *dev = rx_ring->dev;
1136	struct i40e_rx_buffer *rx_bi;
1137	dma_addr_t dma;
1138	void *buffer;
1139	int buf_size;
1140	int i;
1141
1142	if (rx_ring->rx_bi[0].hdr_buf)
1143		return;
1144	/* Make sure the buffers don't cross cache line boundaries. */
1145	buf_size = ALIGN(rx_ring->rx_hdr_len, 256);
1146	buffer = dma_alloc_coherent(dev, buf_size * rx_ring->count,
1147				    &dma, GFP_KERNEL);
1148	if (!buffer)
1149		return;
1150	for (i = 0; i < rx_ring->count; i++) {
1151		rx_bi = &rx_ring->rx_bi[i];
1152		rx_bi->dma = dma + (i * buf_size);
1153		rx_bi->hdr_buf = buffer + (i * buf_size);
1154	}
1155}
1156
1157/**
1158 * i40e_setup_rx_descriptors - Allocate Rx descriptors
1159 * @rx_ring: Rx descriptor ring (for a specific queue) to setup
1160 *
1161 * Returns 0 on success, negative on failure
1162 **/
1163int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
1164{
1165	struct device *dev = rx_ring->dev;
1166	int bi_size;
1167
1168	bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
1169	rx_ring->rx_bi = kzalloc(bi_size, GFP_KERNEL);
1170	if (!rx_ring->rx_bi)
1171		goto err;
1172
1173	u64_stats_init(&rx_ring->syncp);
1174
1175	/* Round up to nearest 4K */
1176	rx_ring->size = ring_is_16byte_desc_enabled(rx_ring)
1177		? rx_ring->count * sizeof(union i40e_16byte_rx_desc)
1178		: rx_ring->count * sizeof(union i40e_32byte_rx_desc);
1179	rx_ring->size = ALIGN(rx_ring->size, 4096);
1180	rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
1181					   &rx_ring->dma, GFP_KERNEL);
1182
1183	if (!rx_ring->desc) {
1184		dev_info(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
1185			 rx_ring->size);
1186		goto err;
1187	}
1188
1189	rx_ring->next_to_clean = 0;
1190	rx_ring->next_to_use = 0;
1191
1192	return 0;
1193err:
1194	kfree(rx_ring->rx_bi);
1195	rx_ring->rx_bi = NULL;
1196	return -ENOMEM;
1197}
1198
1199/**
1200 * i40e_release_rx_desc - Store the new tail and head values
1201 * @rx_ring: ring to bump
1202 * @val: new head index
1203 **/
1204static inline void i40e_release_rx_desc(struct i40e_ring *rx_ring, u32 val)
1205{
1206	rx_ring->next_to_use = val;
1207	/* Force memory writes to complete before letting h/w
1208	 * know there are new descriptors to fetch.  (Only
1209	 * applicable for weak-ordered memory model archs,
1210	 * such as IA-64).
1211	 */
1212	wmb();
1213	writel(val, rx_ring->tail);
1214}
1215
1216/**
1217 * i40e_alloc_rx_buffers_ps - Replace used receive buffers; packet split
1218 * @rx_ring: ring to place buffers on
1219 * @cleaned_count: number of buffers to replace
1220 **/
1221void i40e_alloc_rx_buffers_ps(struct i40e_ring *rx_ring, u16 cleaned_count)
1222{
1223	u16 i = rx_ring->next_to_use;
1224	union i40e_rx_desc *rx_desc;
1225	struct i40e_rx_buffer *bi;
1226
1227	/* do nothing if no valid netdev defined */
1228	if (!rx_ring->netdev || !cleaned_count)
1229		return;
1230
1231	while (cleaned_count--) {
1232		rx_desc = I40E_RX_DESC(rx_ring, i);
1233		bi = &rx_ring->rx_bi[i];
1234
1235		if (bi->skb) /* desc is in use */
1236			goto no_buffers;
1237		if (!bi->page) {
1238			bi->page = alloc_page(GFP_ATOMIC);
1239			if (!bi->page) {
1240				rx_ring->rx_stats.alloc_page_failed++;
1241				goto no_buffers;
1242			}
1243		}
1244
1245		if (!bi->page_dma) {
1246			/* use a half page if we're re-using */
1247			bi->page_offset ^= PAGE_SIZE / 2;
1248			bi->page_dma = dma_map_page(rx_ring->dev,
1249						    bi->page,
1250						    bi->page_offset,
1251						    PAGE_SIZE / 2,
1252						    DMA_FROM_DEVICE);
1253			if (dma_mapping_error(rx_ring->dev,
1254					      bi->page_dma)) {
1255				rx_ring->rx_stats.alloc_page_failed++;
1256				bi->page_dma = 0;
1257				goto no_buffers;
1258			}
1259		}
1260
1261		dma_sync_single_range_for_device(rx_ring->dev,
1262						 bi->dma,
1263						 0,
1264						 rx_ring->rx_hdr_len,
1265						 DMA_FROM_DEVICE);
1266		/* Refresh the desc even if buffer_addrs didn't change
1267		 * because each write-back erases this info.
1268		 */
1269		rx_desc->read.pkt_addr = cpu_to_le64(bi->page_dma);
1270		rx_desc->read.hdr_addr = cpu_to_le64(bi->dma);
1271		i++;
1272		if (i == rx_ring->count)
1273			i = 0;
1274	}
1275
1276no_buffers:
1277	if (rx_ring->next_to_use != i)
1278		i40e_release_rx_desc(rx_ring, i);
1279}
1280
1281/**
1282 * i40e_alloc_rx_buffers_1buf - Replace used receive buffers; single buffer
1283 * @rx_ring: ring to place buffers on
1284 * @cleaned_count: number of buffers to replace
1285 **/
1286void i40e_alloc_rx_buffers_1buf(struct i40e_ring *rx_ring, u16 cleaned_count)
1287{
1288	u16 i = rx_ring->next_to_use;
1289	union i40e_rx_desc *rx_desc;
1290	struct i40e_rx_buffer *bi;
1291	struct sk_buff *skb;
1292
1293	/* do nothing if no valid netdev defined */
1294	if (!rx_ring->netdev || !cleaned_count)
1295		return;
1296
1297	while (cleaned_count--) {
1298		rx_desc = I40E_RX_DESC(rx_ring, i);
1299		bi = &rx_ring->rx_bi[i];
1300		skb = bi->skb;
1301
1302		if (!skb) {
1303			skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
1304							rx_ring->rx_buf_len);
1305			if (!skb) {
1306				rx_ring->rx_stats.alloc_buff_failed++;
1307				goto no_buffers;
1308			}
1309			/* initialize queue mapping */
1310			skb_record_rx_queue(skb, rx_ring->queue_index);
1311			bi->skb = skb;
1312		}
1313
1314		if (!bi->dma) {
1315			bi->dma = dma_map_single(rx_ring->dev,
1316						 skb->data,
1317						 rx_ring->rx_buf_len,
1318						 DMA_FROM_DEVICE);
1319			if (dma_mapping_error(rx_ring->dev, bi->dma)) {
1320				rx_ring->rx_stats.alloc_buff_failed++;
1321				bi->dma = 0;
1322				goto no_buffers;
1323			}
1324		}
1325
1326		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
1327		rx_desc->read.hdr_addr = 0;
1328		i++;
1329		if (i == rx_ring->count)
1330			i = 0;
1331	}
1332
1333no_buffers:
1334	if (rx_ring->next_to_use != i)
1335		i40e_release_rx_desc(rx_ring, i);
1336}
1337
1338/**
1339 * i40e_receive_skb - Send a completed packet up the stack
1340 * @rx_ring:  rx ring in play
1341 * @skb: packet to send up
1342 * @vlan_tag: vlan tag for packet
1343 **/
1344static void i40e_receive_skb(struct i40e_ring *rx_ring,
1345			     struct sk_buff *skb, u16 vlan_tag)
1346{
1347	struct i40e_q_vector *q_vector = rx_ring->q_vector;
1348	struct i40e_vsi *vsi = rx_ring->vsi;
1349	u64 flags = vsi->back->flags;
1350
1351	if (vlan_tag & VLAN_VID_MASK)
1352		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tag);
1353
1354	if (flags & I40E_FLAG_IN_NETPOLL)
1355		netif_rx(skb);
1356	else
1357		napi_gro_receive(&q_vector->napi, skb);
1358}
1359
1360/**
1361 * i40e_rx_checksum - Indicate in skb if hw indicated a good cksum
1362 * @vsi: the VSI we care about
1363 * @skb: skb currently being received and modified
1364 * @rx_status: status value of last descriptor in packet
1365 * @rx_error: error value of last descriptor in packet
1366 * @rx_ptype: ptype value of last descriptor in packet
1367 **/
1368static inline void i40e_rx_checksum(struct i40e_vsi *vsi,
1369				    struct sk_buff *skb,
1370				    u32 rx_status,
1371				    u32 rx_error,
1372				    u16 rx_ptype)
1373{
1374	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(rx_ptype);
1375	bool ipv4 = false, ipv6 = false;
1376	bool ipv4_tunnel, ipv6_tunnel;
1377	__wsum rx_udp_csum;
1378	struct iphdr *iph;
1379	__sum16 csum;
1380
1381	ipv4_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT4_MAC_PAY3) &&
1382		     (rx_ptype <= I40E_RX_PTYPE_GRENAT4_MACVLAN_IPV6_ICMP_PAY4);
1383	ipv6_tunnel = (rx_ptype >= I40E_RX_PTYPE_GRENAT6_MAC_PAY3) &&
1384		     (rx_ptype <= I40E_RX_PTYPE_GRENAT6_MACVLAN_IPV6_ICMP_PAY4);
1385
1386	skb->ip_summed = CHECKSUM_NONE;
1387
1388	/* Rx csum enabled and ip headers found? */
1389	if (!(vsi->netdev->features & NETIF_F_RXCSUM))
1390		return;
1391
1392	/* did the hardware decode the packet and checksum? */
1393	if (!(rx_status & (1 << I40E_RX_DESC_STATUS_L3L4P_SHIFT)))
1394		return;
1395
1396	/* both known and outer_ip must be set for the below code to work */
1397	if (!(decoded.known && decoded.outer_ip))
1398		return;
1399
1400	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1401	    decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV4)
1402		ipv4 = true;
1403	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1404		 decoded.outer_ip_ver == I40E_RX_PTYPE_OUTER_IPV6)
1405		ipv6 = true;
1406
1407	if (ipv4 &&
1408	    (rx_error & ((1 << I40E_RX_DESC_ERROR_IPE_SHIFT) |
1409			 (1 << I40E_RX_DESC_ERROR_EIPE_SHIFT))))
1410		goto checksum_fail;
1411
1412	/* likely incorrect csum if alternate IP extension headers found */
1413	if (ipv6 &&
1414	    rx_status & (1 << I40E_RX_DESC_STATUS_IPV6EXADD_SHIFT))
1415		/* don't increment checksum err here, non-fatal err */
1416		return;
1417
1418	/* there was some L4 error, count error and punt packet to the stack */
1419	if (rx_error & (1 << I40E_RX_DESC_ERROR_L4E_SHIFT))
1420		goto checksum_fail;
1421
1422	/* handle packets that were not able to be checksummed due
1423	 * to arrival speed, in this case the stack can compute
1424	 * the csum.
1425	 */
1426	if (rx_error & (1 << I40E_RX_DESC_ERROR_PPRS_SHIFT))
1427		return;
1428
1429	/* If VXLAN traffic has an outer UDPv4 checksum we need to check
1430	 * it in the driver, hardware does not do it for us.
1431	 * Since L3L4P bit was set we assume a valid IHL value (>=5)
1432	 * so the total length of IPv4 header is IHL*4 bytes
1433	 * The UDP_0 bit *may* bet set if the *inner* header is UDP
1434	 */
1435	if (ipv4_tunnel) {
1436		skb->transport_header = skb->mac_header +
1437					sizeof(struct ethhdr) +
1438					(ip_hdr(skb)->ihl * 4);
1439
1440		/* Add 4 bytes for VLAN tagged packets */
1441		skb->transport_header += (skb->protocol == htons(ETH_P_8021Q) ||
1442					  skb->protocol == htons(ETH_P_8021AD))
1443					  ? VLAN_HLEN : 0;
1444
1445		if ((ip_hdr(skb)->protocol == IPPROTO_UDP) &&
1446		    (udp_hdr(skb)->check != 0)) {
1447			rx_udp_csum = udp_csum(skb);
1448			iph = ip_hdr(skb);
1449			csum = csum_tcpudp_magic(
1450					iph->saddr, iph->daddr,
1451					(skb->len - skb_transport_offset(skb)),
1452					IPPROTO_UDP, rx_udp_csum);
1453
1454			if (udp_hdr(skb)->check != csum)
1455				goto checksum_fail;
1456
1457		} /* else its GRE and so no outer UDP header */
1458	}
1459
1460	skb->ip_summed = CHECKSUM_UNNECESSARY;
1461	skb->csum_level = ipv4_tunnel || ipv6_tunnel;
1462
1463	return;
1464
1465checksum_fail:
1466	vsi->back->hw_csum_rx_error++;
1467}
1468
1469/**
1470 * i40e_rx_hash - returns the hash value from the Rx descriptor
1471 * @ring: descriptor ring
1472 * @rx_desc: specific descriptor
1473 **/
1474static inline u32 i40e_rx_hash(struct i40e_ring *ring,
1475			       union i40e_rx_desc *rx_desc)
1476{
1477	const __le64 rss_mask =
1478		cpu_to_le64((u64)I40E_RX_DESC_FLTSTAT_RSS_HASH <<
1479			    I40E_RX_DESC_STATUS_FLTSTAT_SHIFT);
1480
1481	if ((ring->netdev->features & NETIF_F_RXHASH) &&
1482	    (rx_desc->wb.qword1.status_error_len & rss_mask) == rss_mask)
1483		return le32_to_cpu(rx_desc->wb.qword0.hi_dword.rss);
1484	else
1485		return 0;
1486}
1487
1488/**
1489 * i40e_ptype_to_hash - get a hash type
1490 * @ptype: the ptype value from the descriptor
1491 *
1492 * Returns a hash type to be used by skb_set_hash
1493 **/
1494static inline enum pkt_hash_types i40e_ptype_to_hash(u8 ptype)
1495{
1496	struct i40e_rx_ptype_decoded decoded = decode_rx_desc_ptype(ptype);
1497
1498	if (!decoded.known)
1499		return PKT_HASH_TYPE_NONE;
1500
1501	if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1502	    decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY4)
1503		return PKT_HASH_TYPE_L4;
1504	else if (decoded.outer_ip == I40E_RX_PTYPE_OUTER_IP &&
1505		 decoded.payload_layer == I40E_RX_PTYPE_PAYLOAD_LAYER_PAY3)
1506		return PKT_HASH_TYPE_L3;
1507	else
1508		return PKT_HASH_TYPE_L2;
1509}
1510
1511/**
1512 * i40e_clean_rx_irq_ps - Reclaim resources after receive; packet split
1513 * @rx_ring:  rx ring to clean
1514 * @budget:   how many cleans we're allowed
1515 *
1516 * Returns true if there's any budget left (e.g. the clean is finished)
1517 **/
1518static int i40e_clean_rx_irq_ps(struct i40e_ring *rx_ring, int budget)
1519{
1520	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1521	u16 rx_packet_len, rx_header_len, rx_sph, rx_hbo;
1522	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1523	const int current_node = numa_node_id();
1524	struct i40e_vsi *vsi = rx_ring->vsi;
1525	u16 i = rx_ring->next_to_clean;
1526	union i40e_rx_desc *rx_desc;
1527	u32 rx_error, rx_status;
1528	u8 rx_ptype;
1529	u64 qword;
1530
1531	if (budget <= 0)
1532		return 0;
1533
1534	do {
1535		struct i40e_rx_buffer *rx_bi;
1536		struct sk_buff *skb;
1537		u16 vlan_tag;
1538		/* return some buffers to hardware, one at a time is too slow */
1539		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1540			i40e_alloc_rx_buffers_ps(rx_ring, cleaned_count);
1541			cleaned_count = 0;
1542		}
1543
1544		i = rx_ring->next_to_clean;
1545		rx_desc = I40E_RX_DESC(rx_ring, i);
1546		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1547		rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1548			I40E_RXD_QW1_STATUS_SHIFT;
1549
1550		if (!(rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)))
1551			break;
1552
1553		/* This memory barrier is needed to keep us from reading
1554		 * any other fields out of the rx_desc until we know the
1555		 * DD bit is set.
1556		 */
1557		dma_rmb();
1558		if (i40e_rx_is_programming_status(qword)) {
1559			i40e_clean_programming_status(rx_ring, rx_desc);
1560			I40E_RX_INCREMENT(rx_ring, i);
1561			continue;
1562		}
1563		rx_bi = &rx_ring->rx_bi[i];
1564		skb = rx_bi->skb;
1565		if (likely(!skb)) {
1566			skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
1567							rx_ring->rx_hdr_len);
1568			if (!skb) {
1569				rx_ring->rx_stats.alloc_buff_failed++;
1570				break;
1571			}
1572
1573			/* initialize queue mapping */
1574			skb_record_rx_queue(skb, rx_ring->queue_index);
1575			/* we are reusing so sync this buffer for CPU use */
1576			dma_sync_single_range_for_cpu(rx_ring->dev,
1577						      rx_bi->dma,
1578						      0,
1579						      rx_ring->rx_hdr_len,
1580						      DMA_FROM_DEVICE);
1581		}
1582		rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
1583				I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
1584		rx_header_len = (qword & I40E_RXD_QW1_LENGTH_HBUF_MASK) >>
1585				I40E_RXD_QW1_LENGTH_HBUF_SHIFT;
1586		rx_sph = (qword & I40E_RXD_QW1_LENGTH_SPH_MASK) >>
1587			 I40E_RXD_QW1_LENGTH_SPH_SHIFT;
1588
1589		rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1590			   I40E_RXD_QW1_ERROR_SHIFT;
1591		rx_hbo = rx_error & (1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1592		rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1593
1594		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1595			   I40E_RXD_QW1_PTYPE_SHIFT;
1596		prefetch(rx_bi->page);
1597		rx_bi->skb = NULL;
1598		cleaned_count++;
1599		if (rx_hbo || rx_sph) {
1600			int len;
1601			if (rx_hbo)
1602				len = I40E_RX_HDR_SIZE;
1603			else
1604				len = rx_header_len;
1605			memcpy(__skb_put(skb, len), rx_bi->hdr_buf, len);
1606		} else if (skb->len == 0) {
1607			int len;
1608
1609			len = (rx_packet_len > skb_headlen(skb) ?
1610				skb_headlen(skb) : rx_packet_len);
1611			memcpy(__skb_put(skb, len),
1612			       rx_bi->page + rx_bi->page_offset,
1613			       len);
1614			rx_bi->page_offset += len;
1615			rx_packet_len -= len;
1616		}
1617
1618		/* Get the rest of the data if this was a header split */
1619		if (rx_packet_len) {
1620			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
1621					   rx_bi->page,
1622					   rx_bi->page_offset,
1623					   rx_packet_len);
1624
1625			skb->len += rx_packet_len;
1626			skb->data_len += rx_packet_len;
1627			skb->truesize += rx_packet_len;
1628
1629			if ((page_count(rx_bi->page) == 1) &&
1630			    (page_to_nid(rx_bi->page) == current_node))
1631				get_page(rx_bi->page);
1632			else
1633				rx_bi->page = NULL;
1634
1635			dma_unmap_page(rx_ring->dev,
1636				       rx_bi->page_dma,
1637				       PAGE_SIZE / 2,
1638				       DMA_FROM_DEVICE);
1639			rx_bi->page_dma = 0;
1640		}
1641		I40E_RX_INCREMENT(rx_ring, i);
1642
1643		if (unlikely(
1644		    !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1645			struct i40e_rx_buffer *next_buffer;
1646
1647			next_buffer = &rx_ring->rx_bi[i];
1648			next_buffer->skb = skb;
1649			rx_ring->rx_stats.non_eop_descs++;
1650			continue;
1651		}
1652
1653		/* ERR_MASK will only have valid bits if EOP set */
1654		if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1655			dev_kfree_skb_any(skb);
1656			/* TODO: shouldn't we increment a counter indicating the
1657			 * drop?
1658			 */
1659			continue;
1660		}
1661
1662		skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1663			     i40e_ptype_to_hash(rx_ptype));
1664		if (unlikely(rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK)) {
1665			i40e_ptp_rx_hwtstamp(vsi->back, skb, (rx_status &
1666					   I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1667					   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT);
1668			rx_ring->last_rx_timestamp = jiffies;
1669		}
1670
1671		/* probably a little skewed due to removing CRC */
1672		total_rx_bytes += skb->len;
1673		total_rx_packets++;
1674
1675		skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1676
1677		i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1678
1679		vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1680			 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1681			 : 0;
1682#ifdef I40E_FCOE
1683		if (!i40e_fcoe_handle_offload(rx_ring, rx_desc, skb)) {
1684			dev_kfree_skb_any(skb);
1685			continue;
1686		}
1687#endif
1688		skb_mark_napi_id(skb, &rx_ring->q_vector->napi);
1689		i40e_receive_skb(rx_ring, skb, vlan_tag);
1690
1691		rx_ring->netdev->last_rx = jiffies;
1692		rx_desc->wb.qword1.status_error_len = 0;
1693
1694	} while (likely(total_rx_packets < budget));
1695
1696	u64_stats_update_begin(&rx_ring->syncp);
1697	rx_ring->stats.packets += total_rx_packets;
1698	rx_ring->stats.bytes += total_rx_bytes;
1699	u64_stats_update_end(&rx_ring->syncp);
1700	rx_ring->q_vector->rx.total_packets += total_rx_packets;
1701	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1702
1703	return total_rx_packets;
1704}
1705
1706/**
1707 * i40e_clean_rx_irq_1buf - Reclaim resources after receive; single buffer
1708 * @rx_ring:  rx ring to clean
1709 * @budget:   how many cleans we're allowed
1710 *
1711 * Returns number of packets cleaned
1712 **/
1713static int i40e_clean_rx_irq_1buf(struct i40e_ring *rx_ring, int budget)
1714{
1715	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
1716	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
1717	struct i40e_vsi *vsi = rx_ring->vsi;
1718	union i40e_rx_desc *rx_desc;
1719	u32 rx_error, rx_status;
1720	u16 rx_packet_len;
1721	u8 rx_ptype;
1722	u64 qword;
1723	u16 i;
1724
1725	do {
1726		struct i40e_rx_buffer *rx_bi;
1727		struct sk_buff *skb;
1728		u16 vlan_tag;
1729		/* return some buffers to hardware, one at a time is too slow */
1730		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
1731			i40e_alloc_rx_buffers_1buf(rx_ring, cleaned_count);
1732			cleaned_count = 0;
1733		}
1734
1735		i = rx_ring->next_to_clean;
1736		rx_desc = I40E_RX_DESC(rx_ring, i);
1737		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
1738		rx_status = (qword & I40E_RXD_QW1_STATUS_MASK) >>
1739			I40E_RXD_QW1_STATUS_SHIFT;
1740
1741		if (!(rx_status & (1 << I40E_RX_DESC_STATUS_DD_SHIFT)))
1742			break;
1743
1744		/* This memory barrier is needed to keep us from reading
1745		 * any other fields out of the rx_desc until we know the
1746		 * DD bit is set.
1747		 */
1748		dma_rmb();
1749
1750		if (i40e_rx_is_programming_status(qword)) {
1751			i40e_clean_programming_status(rx_ring, rx_desc);
1752			I40E_RX_INCREMENT(rx_ring, i);
1753			continue;
1754		}
1755		rx_bi = &rx_ring->rx_bi[i];
1756		skb = rx_bi->skb;
1757		prefetch(skb->data);
1758
1759		rx_packet_len = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
1760				I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
1761
1762		rx_error = (qword & I40E_RXD_QW1_ERROR_MASK) >>
1763			   I40E_RXD_QW1_ERROR_SHIFT;
1764		rx_error &= ~(1 << I40E_RX_DESC_ERROR_HBO_SHIFT);
1765
1766		rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
1767			   I40E_RXD_QW1_PTYPE_SHIFT;
1768		rx_bi->skb = NULL;
1769		cleaned_count++;
1770
1771		/* Get the header and possibly the whole packet
1772		 * If this is an skb from previous receive dma will be 0
1773		 */
1774		skb_put(skb, rx_packet_len);
1775		dma_unmap_single(rx_ring->dev, rx_bi->dma, rx_ring->rx_buf_len,
1776				 DMA_FROM_DEVICE);
1777		rx_bi->dma = 0;
1778
1779		I40E_RX_INCREMENT(rx_ring, i);
1780
1781		if (unlikely(
1782		    !(rx_status & (1 << I40E_RX_DESC_STATUS_EOF_SHIFT)))) {
1783			rx_ring->rx_stats.non_eop_descs++;
1784			continue;
1785		}
1786
1787		/* ERR_MASK will only have valid bits if EOP set */
1788		if (unlikely(rx_error & (1 << I40E_RX_DESC_ERROR_RXE_SHIFT))) {
1789			dev_kfree_skb_any(skb);
1790			/* TODO: shouldn't we increment a counter indicating the
1791			 * drop?
1792			 */
1793			continue;
1794		}
1795
1796		skb_set_hash(skb, i40e_rx_hash(rx_ring, rx_desc),
1797			     i40e_ptype_to_hash(rx_ptype));
1798		if (unlikely(rx_status & I40E_RXD_QW1_STATUS_TSYNVALID_MASK)) {
1799			i40e_ptp_rx_hwtstamp(vsi->back, skb, (rx_status &
1800					   I40E_RXD_QW1_STATUS_TSYNINDX_MASK) >>
1801					   I40E_RXD_QW1_STATUS_TSYNINDX_SHIFT);
1802			rx_ring->last_rx_timestamp = jiffies;
1803		}
1804
1805		/* probably a little skewed due to removing CRC */
1806		total_rx_bytes += skb->len;
1807		total_rx_packets++;
1808
1809		skb->protocol = eth_type_trans(skb, rx_ring->netdev);
1810
1811		i40e_rx_checksum(vsi, skb, rx_status, rx_error, rx_ptype);
1812
1813		vlan_tag = rx_status & (1 << I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)
1814			 ? le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1)
1815			 : 0;
1816#ifdef I40E_FCOE
1817		if (!i40e_fcoe_handle_offload(rx_ring, rx_desc, skb)) {
1818			dev_kfree_skb_any(skb);
1819			continue;
1820		}
1821#endif
1822		i40e_receive_skb(rx_ring, skb, vlan_tag);
1823
1824		rx_ring->netdev->last_rx = jiffies;
1825		rx_desc->wb.qword1.status_error_len = 0;
1826	} while (likely(total_rx_packets < budget));
1827
1828	u64_stats_update_begin(&rx_ring->syncp);
1829	rx_ring->stats.packets += total_rx_packets;
1830	rx_ring->stats.bytes += total_rx_bytes;
1831	u64_stats_update_end(&rx_ring->syncp);
1832	rx_ring->q_vector->rx.total_packets += total_rx_packets;
1833	rx_ring->q_vector->rx.total_bytes += total_rx_bytes;
1834
1835	return total_rx_packets;
1836}
1837
1838/**
1839 * i40e_napi_poll - NAPI polling Rx/Tx cleanup routine
1840 * @napi: napi struct with our devices info in it
1841 * @budget: amount of work driver is allowed to do this pass, in packets
1842 *
1843 * This function will clean all queues associated with a q_vector.
1844 *
1845 * Returns the amount of work done
1846 **/
1847int i40e_napi_poll(struct napi_struct *napi, int budget)
1848{
1849	struct i40e_q_vector *q_vector =
1850			       container_of(napi, struct i40e_q_vector, napi);
1851	struct i40e_vsi *vsi = q_vector->vsi;
1852	struct i40e_ring *ring;
1853	bool clean_complete = true;
1854	bool arm_wb = false;
1855	int budget_per_ring;
1856	int cleaned;
1857
1858	if (test_bit(__I40E_DOWN, &vsi->state)) {
1859		napi_complete(napi);
1860		return 0;
1861	}
1862
1863	/* Since the actual Tx work is minimal, we can give the Tx a larger
1864	 * budget and be more aggressive about cleaning up the Tx descriptors.
1865	 */
1866	i40e_for_each_ring(ring, q_vector->tx) {
1867		clean_complete &= i40e_clean_tx_irq(ring, vsi->work_limit);
1868		arm_wb |= ring->arm_wb;
1869	}
1870
1871	/* We attempt to distribute budget to each Rx queue fairly, but don't
1872	 * allow the budget to go below 1 because that would exit polling early.
1873	 */
1874	budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
1875
1876	i40e_for_each_ring(ring, q_vector->rx) {
1877		if (ring_is_ps_enabled(ring))
1878			cleaned = i40e_clean_rx_irq_ps(ring, budget_per_ring);
1879		else
1880			cleaned = i40e_clean_rx_irq_1buf(ring, budget_per_ring);
1881		/* if we didn't clean as many as budgeted, we must be done */
1882		clean_complete &= (budget_per_ring != cleaned);
1883	}
1884
1885	/* If work not completed, return budget and polling will return */
1886	if (!clean_complete) {
1887		if (arm_wb)
1888			i40e_force_wb(vsi, q_vector);
1889		return budget;
1890	}
1891
1892	/* Work is done so exit the polling mode and re-enable the interrupt */
1893	napi_complete(napi);
1894	if (ITR_IS_DYNAMIC(vsi->rx_itr_setting) ||
1895	    ITR_IS_DYNAMIC(vsi->tx_itr_setting))
1896		i40e_update_dynamic_itr(q_vector);
1897
1898	if (!test_bit(__I40E_DOWN, &vsi->state)) {
1899		if (vsi->back->flags & I40E_FLAG_MSIX_ENABLED) {
1900			i40e_irq_dynamic_enable(vsi,
1901					q_vector->v_idx + vsi->base_vector);
1902		} else {
1903			struct i40e_hw *hw = &vsi->back->hw;
1904			/* We re-enable the queue 0 cause, but
1905			 * don't worry about dynamic_enable
1906			 * because we left it on for the other
1907			 * possible interrupts during napi
1908			 */
1909			u32 qval = rd32(hw, I40E_QINT_RQCTL(0));
1910			qval |= I40E_QINT_RQCTL_CAUSE_ENA_MASK;
1911			wr32(hw, I40E_QINT_RQCTL(0), qval);
1912
1913			qval = rd32(hw, I40E_QINT_TQCTL(0));
1914			qval |= I40E_QINT_TQCTL_CAUSE_ENA_MASK;
1915			wr32(hw, I40E_QINT_TQCTL(0), qval);
1916
1917			i40e_irq_dynamic_enable_icr0(vsi->back);
1918		}
1919	}
1920
1921	return 0;
1922}
1923
1924/**
1925 * i40e_atr - Add a Flow Director ATR filter
1926 * @tx_ring:  ring to add programming descriptor to
1927 * @skb:      send buffer
1928 * @flags:    send flags
1929 * @protocol: wire protocol
1930 **/
1931static void i40e_atr(struct i40e_ring *tx_ring, struct sk_buff *skb,
1932		     u32 flags, __be16 protocol)
1933{
1934	struct i40e_filter_program_desc *fdir_desc;
1935	struct i40e_pf *pf = tx_ring->vsi->back;
1936	union {
1937		unsigned char *network;
1938		struct iphdr *ipv4;
1939		struct ipv6hdr *ipv6;
1940	} hdr;
1941	struct tcphdr *th;
1942	unsigned int hlen;
1943	u32 flex_ptype, dtype_cmd;
1944	u16 i;
1945
1946	/* make sure ATR is enabled */
1947	if (!(pf->flags & I40E_FLAG_FD_ATR_ENABLED))
1948		return;
1949
1950	if ((pf->auto_disable_flags & I40E_FLAG_FD_ATR_ENABLED))
1951		return;
1952
1953	/* if sampling is disabled do nothing */
1954	if (!tx_ring->atr_sample_rate)
1955		return;
1956
1957	/* snag network header to get L4 type and address */
1958	hdr.network = skb_network_header(skb);
1959
1960	/* Currently only IPv4/IPv6 with TCP is supported */
1961	if (protocol == htons(ETH_P_IP)) {
1962		if (hdr.ipv4->protocol != IPPROTO_TCP)
1963			return;
1964
1965		/* access ihl as a u8 to avoid unaligned access on ia64 */
1966		hlen = (hdr.network[0] & 0x0F) << 2;
1967	} else if (protocol == htons(ETH_P_IPV6)) {
1968		if (hdr.ipv6->nexthdr != IPPROTO_TCP)
1969			return;
1970
1971		hlen = sizeof(struct ipv6hdr);
1972	} else {
1973		return;
1974	}
1975
1976	th = (struct tcphdr *)(hdr.network + hlen);
1977
1978	/* Due to lack of space, no more new filters can be programmed */
1979	if (th->syn && (pf->auto_disable_flags & I40E_FLAG_FD_ATR_ENABLED))
1980		return;
1981
1982	tx_ring->atr_count++;
1983
1984	/* sample on all syn/fin/rst packets or once every atr sample rate */
1985	if (!th->fin &&
1986	    !th->syn &&
1987	    !th->rst &&
1988	    (tx_ring->atr_count < tx_ring->atr_sample_rate))
1989		return;
1990
1991	tx_ring->atr_count = 0;
1992
1993	/* grab the next descriptor */
1994	i = tx_ring->next_to_use;
1995	fdir_desc = I40E_TX_FDIRDESC(tx_ring, i);
1996
1997	i++;
1998	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
1999
2000	flex_ptype = (tx_ring->queue_index << I40E_TXD_FLTR_QW0_QINDEX_SHIFT) &
2001		      I40E_TXD_FLTR_QW0_QINDEX_MASK;
2002	flex_ptype |= (protocol == htons(ETH_P_IP)) ?
2003		      (I40E_FILTER_PCTYPE_NONF_IPV4_TCP <<
2004		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT) :
2005		      (I40E_FILTER_PCTYPE_NONF_IPV6_TCP <<
2006		       I40E_TXD_FLTR_QW0_PCTYPE_SHIFT);
2007
2008	flex_ptype |= tx_ring->vsi->id << I40E_TXD_FLTR_QW0_DEST_VSI_SHIFT;
2009
2010	dtype_cmd = I40E_TX_DESC_DTYPE_FILTER_PROG;
2011
2012	dtype_cmd |= (th->fin || th->rst) ?
2013		     (I40E_FILTER_PROGRAM_DESC_PCMD_REMOVE <<
2014		      I40E_TXD_FLTR_QW1_PCMD_SHIFT) :
2015		     (I40E_FILTER_PROGRAM_DESC_PCMD_ADD_UPDATE <<
2016		      I40E_TXD_FLTR_QW1_PCMD_SHIFT);
2017
2018	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_DEST_DIRECT_PACKET_QINDEX <<
2019		     I40E_TXD_FLTR_QW1_DEST_SHIFT;
2020
2021	dtype_cmd |= I40E_FILTER_PROGRAM_DESC_FD_STATUS_FD_ID <<
2022		     I40E_TXD_FLTR_QW1_FD_STATUS_SHIFT;
2023
2024	dtype_cmd |= I40E_TXD_FLTR_QW1_CNT_ENA_MASK;
2025	dtype_cmd |=
2026		((u32)pf->fd_atr_cnt_idx << I40E_TXD_FLTR_QW1_CNTINDEX_SHIFT) &
2027		I40E_TXD_FLTR_QW1_CNTINDEX_MASK;
2028
2029	fdir_desc->qindex_flex_ptype_vsi = cpu_to_le32(flex_ptype);
2030	fdir_desc->rsvd = cpu_to_le32(0);
2031	fdir_desc->dtype_cmd_cntindex = cpu_to_le32(dtype_cmd);
2032	fdir_desc->fd_id = cpu_to_le32(0);
2033}
2034
2035/**
2036 * i40e_tx_prepare_vlan_flags - prepare generic TX VLAN tagging flags for HW
2037 * @skb:     send buffer
2038 * @tx_ring: ring to send buffer on
2039 * @flags:   the tx flags to be set
2040 *
2041 * Checks the skb and set up correspondingly several generic transmit flags
2042 * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2043 *
2044 * Returns error code indicate the frame should be dropped upon error and the
2045 * otherwise  returns 0 to indicate the flags has been set properly.
2046 **/
2047#ifdef I40E_FCOE
2048int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2049			       struct i40e_ring *tx_ring,
2050			       u32 *flags)
2051#else
2052static int i40e_tx_prepare_vlan_flags(struct sk_buff *skb,
2053				      struct i40e_ring *tx_ring,
2054				      u32 *flags)
2055#endif
2056{
2057	__be16 protocol = skb->protocol;
2058	u32  tx_flags = 0;
2059
2060	if (protocol == htons(ETH_P_8021Q) &&
2061	    !(tx_ring->netdev->features & NETIF_F_HW_VLAN_CTAG_TX)) {
2062		/* When HW VLAN acceleration is turned off by the user the
2063		 * stack sets the protocol to 8021q so that the driver
2064		 * can take any steps required to support the SW only
2065		 * VLAN handling.  In our case the driver doesn't need
2066		 * to take any further steps so just set the protocol
2067		 * to the encapsulated ethertype.
2068		 */
2069		skb->protocol = vlan_get_protocol(skb);
2070		goto out;
2071	}
2072
2073	/* if we have a HW VLAN tag being added, default to the HW one */
2074	if (skb_vlan_tag_present(skb)) {
2075		tx_flags |= skb_vlan_tag_get(skb) << I40E_TX_FLAGS_VLAN_SHIFT;
2076		tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2077	/* else if it is a SW VLAN, check the next protocol and store the tag */
2078	} else if (protocol == htons(ETH_P_8021Q)) {
2079		struct vlan_hdr *vhdr, _vhdr;
2080		vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(_vhdr), &_vhdr);
2081		if (!vhdr)
2082			return -EINVAL;
2083
2084		protocol = vhdr->h_vlan_encapsulated_proto;
2085		tx_flags |= ntohs(vhdr->h_vlan_TCI) << I40E_TX_FLAGS_VLAN_SHIFT;
2086		tx_flags |= I40E_TX_FLAGS_SW_VLAN;
2087	}
2088
2089	if (!(tx_ring->vsi->back->flags & I40E_FLAG_DCB_ENABLED))
2090		goto out;
2091
2092	/* Insert 802.1p priority into VLAN header */
2093	if ((tx_flags & (I40E_TX_FLAGS_HW_VLAN | I40E_TX_FLAGS_SW_VLAN)) ||
2094	    (skb->priority != TC_PRIO_CONTROL)) {
2095		tx_flags &= ~I40E_TX_FLAGS_VLAN_PRIO_MASK;
2096		tx_flags |= (skb->priority & 0x7) <<
2097				I40E_TX_FLAGS_VLAN_PRIO_SHIFT;
2098		if (tx_flags & I40E_TX_FLAGS_SW_VLAN) {
2099			struct vlan_ethhdr *vhdr;
2100			int rc;
2101
2102			rc = skb_cow_head(skb, 0);
2103			if (rc < 0)
2104				return rc;
2105			vhdr = (struct vlan_ethhdr *)skb->data;
2106			vhdr->h_vlan_TCI = htons(tx_flags >>
2107						 I40E_TX_FLAGS_VLAN_SHIFT);
2108		} else {
2109			tx_flags |= I40E_TX_FLAGS_HW_VLAN;
2110		}
2111	}
2112
2113out:
2114	*flags = tx_flags;
2115	return 0;
2116}
2117
2118/**
2119 * i40e_tso - set up the tso context descriptor
2120 * @tx_ring:  ptr to the ring to send
2121 * @skb:      ptr to the skb we're sending
2122 * @tx_flags: the collected send information
2123 * @protocol: the send protocol
2124 * @hdr_len:  ptr to the size of the packet header
2125 * @cd_tunneling: ptr to context descriptor bits
2126 *
2127 * Returns 0 if no TSO can happen, 1 if tso is going, or error
2128 **/
2129static int i40e_tso(struct i40e_ring *tx_ring, struct sk_buff *skb,
2130		    u32 tx_flags, __be16 protocol, u8 *hdr_len,
2131		    u64 *cd_type_cmd_tso_mss, u32 *cd_tunneling)
2132{
2133	u32 cd_cmd, cd_tso_len, cd_mss;
2134	struct ipv6hdr *ipv6h;
2135	struct tcphdr *tcph;
2136	struct iphdr *iph;
2137	u32 l4len;
2138	int err;
2139
2140	if (!skb_is_gso(skb))
2141		return 0;
2142
2143	err = skb_cow_head(skb, 0);
2144	if (err < 0)
2145		return err;
2146
2147	iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
2148	ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
2149
2150	if (iph->version == 4) {
2151		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
2152		iph->tot_len = 0;
2153		iph->check = 0;
2154		tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
2155						 0, IPPROTO_TCP, 0);
2156	} else if (ipv6h->version == 6) {
2157		tcph = skb->encapsulation ? inner_tcp_hdr(skb) : tcp_hdr(skb);
2158		ipv6h->payload_len = 0;
2159		tcph->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
2160					       0, IPPROTO_TCP, 0);
2161	}
2162
2163	l4len = skb->encapsulation ? inner_tcp_hdrlen(skb) : tcp_hdrlen(skb);
2164	*hdr_len = (skb->encapsulation
2165		    ? (skb_inner_transport_header(skb) - skb->data)
2166		    : skb_transport_offset(skb)) + l4len;
2167
2168	/* find the field values */
2169	cd_cmd = I40E_TX_CTX_DESC_TSO;
2170	cd_tso_len = skb->len - *hdr_len;
2171	cd_mss = skb_shinfo(skb)->gso_size;
2172	*cd_type_cmd_tso_mss |= ((u64)cd_cmd << I40E_TXD_CTX_QW1_CMD_SHIFT) |
2173				((u64)cd_tso_len <<
2174				 I40E_TXD_CTX_QW1_TSO_LEN_SHIFT) |
2175				((u64)cd_mss << I40E_TXD_CTX_QW1_MSS_SHIFT);
2176	return 1;
2177}
2178
2179/**
2180 * i40e_tsyn - set up the tsyn context descriptor
2181 * @tx_ring:  ptr to the ring to send
2182 * @skb:      ptr to the skb we're sending
2183 * @tx_flags: the collected send information
2184 *
2185 * Returns 0 if no Tx timestamp can happen and 1 if the timestamp will happen
2186 **/
2187static int i40e_tsyn(struct i40e_ring *tx_ring, struct sk_buff *skb,
2188		     u32 tx_flags, u64 *cd_type_cmd_tso_mss)
2189{
2190	struct i40e_pf *pf;
2191
2192	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2193		return 0;
2194
2195	/* Tx timestamps cannot be sampled when doing TSO */
2196	if (tx_flags & I40E_TX_FLAGS_TSO)
2197		return 0;
2198
2199	/* only timestamp the outbound packet if the user has requested it and
2200	 * we are not already transmitting a packet to be timestamped
2201	 */
2202	pf = i40e_netdev_to_pf(tx_ring->netdev);
2203	if (!(pf->flags & I40E_FLAG_PTP))
2204		return 0;
2205
2206	if (pf->ptp_tx &&
2207	    !test_and_set_bit_lock(__I40E_PTP_TX_IN_PROGRESS, &pf->state)) {
2208		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
2209		pf->ptp_tx_skb = skb_get(skb);
2210	} else {
2211		return 0;
2212	}
2213
2214	*cd_type_cmd_tso_mss |= (u64)I40E_TX_CTX_DESC_TSYN <<
2215				I40E_TXD_CTX_QW1_CMD_SHIFT;
2216
2217	return 1;
2218}
2219
2220/**
2221 * i40e_tx_enable_csum - Enable Tx checksum offloads
2222 * @skb: send buffer
2223 * @tx_flags: Tx flags currently set
2224 * @td_cmd: Tx descriptor command bits to set
2225 * @td_offset: Tx descriptor header offsets to set
2226 * @cd_tunneling: ptr to context desc bits
2227 **/
2228static void i40e_tx_enable_csum(struct sk_buff *skb, u32 tx_flags,
2229				u32 *td_cmd, u32 *td_offset,
2230				struct i40e_ring *tx_ring,
2231				u32 *cd_tunneling)
2232{
2233	struct ipv6hdr *this_ipv6_hdr;
2234	unsigned int this_tcp_hdrlen;
2235	struct iphdr *this_ip_hdr;
2236	u32 network_hdr_len;
2237	u8 l4_hdr = 0;
2238	u32 l4_tunnel = 0;
2239
2240	if (skb->encapsulation) {
2241		switch (ip_hdr(skb)->protocol) {
2242		case IPPROTO_UDP:
2243			l4_tunnel = I40E_TXD_CTX_UDP_TUNNELING;
2244			break;
2245		default:
2246			return;
2247		}
2248		network_hdr_len = skb_inner_network_header_len(skb);
2249		this_ip_hdr = inner_ip_hdr(skb);
2250		this_ipv6_hdr = inner_ipv6_hdr(skb);
2251		this_tcp_hdrlen = inner_tcp_hdrlen(skb);
2252
2253		if (tx_flags & I40E_TX_FLAGS_IPV4) {
2254
2255			if (tx_flags & I40E_TX_FLAGS_TSO) {
2256				*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV4;
2257				ip_hdr(skb)->check = 0;
2258			} else {
2259				*cd_tunneling |=
2260					 I40E_TX_CTX_EXT_IP_IPV4_NO_CSUM;
2261			}
2262		} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
2263			*cd_tunneling |= I40E_TX_CTX_EXT_IP_IPV6;
2264			if (tx_flags & I40E_TX_FLAGS_TSO)
2265				ip_hdr(skb)->check = 0;
2266		}
2267
2268		/* Now set the ctx descriptor fields */
2269		*cd_tunneling |= (skb_network_header_len(skb) >> 2) <<
2270				   I40E_TXD_CTX_QW0_EXT_IPLEN_SHIFT      |
2271				   l4_tunnel                             |
2272				   ((skb_inner_network_offset(skb) -
2273					skb_transport_offset(skb)) >> 1) <<
2274				   I40E_TXD_CTX_QW0_NATLEN_SHIFT;
2275		if (this_ip_hdr->version == 6) {
2276			tx_flags &= ~I40E_TX_FLAGS_IPV4;
2277			tx_flags |= I40E_TX_FLAGS_IPV6;
2278		}
2279	} else {
2280		network_hdr_len = skb_network_header_len(skb);
2281		this_ip_hdr = ip_hdr(skb);
2282		this_ipv6_hdr = ipv6_hdr(skb);
2283		this_tcp_hdrlen = tcp_hdrlen(skb);
2284	}
2285
2286	/* Enable IP checksum offloads */
2287	if (tx_flags & I40E_TX_FLAGS_IPV4) {
2288		l4_hdr = this_ip_hdr->protocol;
2289		/* the stack computes the IP header already, the only time we
2290		 * need the hardware to recompute it is in the case of TSO.
2291		 */
2292		if (tx_flags & I40E_TX_FLAGS_TSO) {
2293			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4_CSUM;
2294			this_ip_hdr->check = 0;
2295		} else {
2296			*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV4;
2297		}
2298		/* Now set the td_offset for IP header length */
2299		*td_offset = (network_hdr_len >> 2) <<
2300			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2301	} else if (tx_flags & I40E_TX_FLAGS_IPV6) {
2302		l4_hdr = this_ipv6_hdr->nexthdr;
2303		*td_cmd |= I40E_TX_DESC_CMD_IIPT_IPV6;
2304		/* Now set the td_offset for IP header length */
2305		*td_offset = (network_hdr_len >> 2) <<
2306			      I40E_TX_DESC_LENGTH_IPLEN_SHIFT;
2307	}
2308	/* words in MACLEN + dwords in IPLEN + dwords in L4Len */
2309	*td_offset |= (skb_network_offset(skb) >> 1) <<
2310		       I40E_TX_DESC_LENGTH_MACLEN_SHIFT;
2311
2312	/* Enable L4 checksum offloads */
2313	switch (l4_hdr) {
2314	case IPPROTO_TCP:
2315		/* enable checksum offloads */
2316		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_TCP;
2317		*td_offset |= (this_tcp_hdrlen >> 2) <<
2318			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2319		break;
2320	case IPPROTO_SCTP:
2321		/* enable SCTP checksum offload */
2322		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_SCTP;
2323		*td_offset |= (sizeof(struct sctphdr) >> 2) <<
2324			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2325		break;
2326	case IPPROTO_UDP:
2327		/* enable UDP checksum offload */
2328		*td_cmd |= I40E_TX_DESC_CMD_L4T_EOFT_UDP;
2329		*td_offset |= (sizeof(struct udphdr) >> 2) <<
2330			       I40E_TX_DESC_LENGTH_L4_FC_LEN_SHIFT;
2331		break;
2332	default:
2333		break;
2334	}
2335}
2336
2337/**
2338 * i40e_create_tx_ctx Build the Tx context descriptor
2339 * @tx_ring:  ring to create the descriptor on
2340 * @cd_type_cmd_tso_mss: Quad Word 1
2341 * @cd_tunneling: Quad Word 0 - bits 0-31
2342 * @cd_l2tag2: Quad Word 0 - bits 32-63
2343 **/
2344static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
2345			       const u64 cd_type_cmd_tso_mss,
2346			       const u32 cd_tunneling, const u32 cd_l2tag2)
2347{
2348	struct i40e_tx_context_desc *context_desc;
2349	int i = tx_ring->next_to_use;
2350
2351	if ((cd_type_cmd_tso_mss == I40E_TX_DESC_DTYPE_CONTEXT) &&
2352	    !cd_tunneling && !cd_l2tag2)
2353		return;
2354
2355	/* grab the next descriptor */
2356	context_desc = I40E_TX_CTXTDESC(tx_ring, i);
2357
2358	i++;
2359	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2360
2361	/* cpu_to_le32 and assign to struct fields */
2362	context_desc->tunneling_params = cpu_to_le32(cd_tunneling);
2363	context_desc->l2tag2 = cpu_to_le16(cd_l2tag2);
2364	context_desc->rsvd = cpu_to_le16(0);
2365	context_desc->type_cmd_tso_mss = cpu_to_le64(cd_type_cmd_tso_mss);
2366}
2367
2368/**
2369 * __i40e_maybe_stop_tx - 2nd level check for tx stop conditions
2370 * @tx_ring: the ring to be checked
2371 * @size:    the size buffer we want to assure is available
2372 *
2373 * Returns -EBUSY if a stop is needed, else 0
2374 **/
2375static inline int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2376{
2377	netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
2378	/* Memory barrier before checking head and tail */
2379	smp_mb();
2380
2381	/* Check again in a case another CPU has just made room available. */
2382	if (likely(I40E_DESC_UNUSED(tx_ring) < size))
2383		return -EBUSY;
2384
2385	/* A reprieve! - use start_queue because it doesn't call schedule */
2386	netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
2387	++tx_ring->tx_stats.restart_queue;
2388	return 0;
2389}
2390
2391/**
2392 * i40e_maybe_stop_tx - 1st level check for tx stop conditions
2393 * @tx_ring: the ring to be checked
2394 * @size:    the size buffer we want to assure is available
2395 *
2396 * Returns 0 if stop is not needed
2397 **/
2398#ifdef I40E_FCOE
2399int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2400#else
2401static int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
2402#endif
2403{
2404	if (likely(I40E_DESC_UNUSED(tx_ring) >= size))
2405		return 0;
2406	return __i40e_maybe_stop_tx(tx_ring, size);
2407}
2408
2409/**
2410 * i40e_chk_linearize - Check if there are more than 8 fragments per packet
2411 * @skb:      send buffer
2412 * @tx_flags: collected send information
2413 *
2414 * Note: Our HW can't scatter-gather more than 8 fragments to build
2415 * a packet on the wire and so we need to figure out the cases where we
2416 * need to linearize the skb.
2417 **/
2418static bool i40e_chk_linearize(struct sk_buff *skb, u32 tx_flags)
2419{
2420	struct skb_frag_struct *frag;
2421	bool linearize = false;
2422	unsigned int size = 0;
2423	u16 num_frags;
2424	u16 gso_segs;
2425
2426	num_frags = skb_shinfo(skb)->nr_frags;
2427	gso_segs = skb_shinfo(skb)->gso_segs;
2428
2429	if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO)) {
2430		u16 j = 0;
2431
2432		if (num_frags < (I40E_MAX_BUFFER_TXD))
2433			goto linearize_chk_done;
2434		/* try the simple math, if we have too many frags per segment */
2435		if (DIV_ROUND_UP((num_frags + gso_segs), gso_segs) >
2436		    I40E_MAX_BUFFER_TXD) {
2437			linearize = true;
2438			goto linearize_chk_done;
2439		}
2440		frag = &skb_shinfo(skb)->frags[0];
2441		/* we might still have more fragments per segment */
2442		do {
2443			size += skb_frag_size(frag);
2444			frag++; j++;
2445			if ((size >= skb_shinfo(skb)->gso_size) &&
2446			    (j < I40E_MAX_BUFFER_TXD)) {
2447				size = (size % skb_shinfo(skb)->gso_size);
2448				j = (size) ? 1 : 0;
2449			}
2450			if (j == I40E_MAX_BUFFER_TXD) {
2451				linearize = true;
2452				break;
2453			}
2454			num_frags--;
2455		} while (num_frags);
2456	} else {
2457		if (num_frags >= I40E_MAX_BUFFER_TXD)
2458			linearize = true;
2459	}
2460
2461linearize_chk_done:
2462	return linearize;
2463}
2464
2465/**
2466 * i40e_tx_map - Build the Tx descriptor
2467 * @tx_ring:  ring to send buffer on
2468 * @skb:      send buffer
2469 * @first:    first buffer info buffer to use
2470 * @tx_flags: collected send information
2471 * @hdr_len:  size of the packet header
2472 * @td_cmd:   the command field in the descriptor
2473 * @td_offset: offset for checksum or crc
2474 **/
2475#ifdef I40E_FCOE
2476void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2477		 struct i40e_tx_buffer *first, u32 tx_flags,
2478		 const u8 hdr_len, u32 td_cmd, u32 td_offset)
2479#else
2480static void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb,
2481			struct i40e_tx_buffer *first, u32 tx_flags,
2482			const u8 hdr_len, u32 td_cmd, u32 td_offset)
2483#endif
2484{
2485	unsigned int data_len = skb->data_len;
2486	unsigned int size = skb_headlen(skb);
2487	struct skb_frag_struct *frag;
2488	struct i40e_tx_buffer *tx_bi;
2489	struct i40e_tx_desc *tx_desc;
2490	u16 i = tx_ring->next_to_use;
2491	u32 td_tag = 0;
2492	dma_addr_t dma;
2493	u16 gso_segs;
2494
2495	if (tx_flags & I40E_TX_FLAGS_HW_VLAN) {
2496		td_cmd |= I40E_TX_DESC_CMD_IL2TAG1;
2497		td_tag = (tx_flags & I40E_TX_FLAGS_VLAN_MASK) >>
2498			 I40E_TX_FLAGS_VLAN_SHIFT;
2499	}
2500
2501	if (tx_flags & (I40E_TX_FLAGS_TSO | I40E_TX_FLAGS_FSO))
2502		gso_segs = skb_shinfo(skb)->gso_segs;
2503	else
2504		gso_segs = 1;
2505
2506	/* multiply data chunks by size of headers */
2507	first->bytecount = skb->len - hdr_len + (gso_segs * hdr_len);
2508	first->gso_segs = gso_segs;
2509	first->skb = skb;
2510	first->tx_flags = tx_flags;
2511
2512	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
2513
2514	tx_desc = I40E_TX_DESC(tx_ring, i);
2515	tx_bi = first;
2516
2517	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
2518		if (dma_mapping_error(tx_ring->dev, dma))
2519			goto dma_error;
2520
2521		/* record length, and DMA address */
2522		dma_unmap_len_set(tx_bi, len, size);
2523		dma_unmap_addr_set(tx_bi, dma, dma);
2524
2525		tx_desc->buffer_addr = cpu_to_le64(dma);
2526
2527		while (unlikely(size > I40E_MAX_DATA_PER_TXD)) {
2528			tx_desc->cmd_type_offset_bsz =
2529				build_ctob(td_cmd, td_offset,
2530					   I40E_MAX_DATA_PER_TXD, td_tag);
2531
2532			tx_desc++;
2533			i++;
2534			if (i == tx_ring->count) {
2535				tx_desc = I40E_TX_DESC(tx_ring, 0);
2536				i = 0;
2537			}
2538
2539			dma += I40E_MAX_DATA_PER_TXD;
2540			size -= I40E_MAX_DATA_PER_TXD;
2541
2542			tx_desc->buffer_addr = cpu_to_le64(dma);
2543		}
2544
2545		if (likely(!data_len))
2546			break;
2547
2548		tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd, td_offset,
2549							  size, td_tag);
2550
2551		tx_desc++;
2552		i++;
2553		if (i == tx_ring->count) {
2554			tx_desc = I40E_TX_DESC(tx_ring, 0);
2555			i = 0;
2556		}
2557
2558		size = skb_frag_size(frag);
2559		data_len -= size;
2560
2561		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
2562				       DMA_TO_DEVICE);
2563
2564		tx_bi = &tx_ring->tx_bi[i];
2565	}
2566
2567	/* Place RS bit on last descriptor of any packet that spans across the
2568	 * 4th descriptor (WB_STRIDE aka 0x3) in a 64B cacheline.
2569	 */
2570	if (((i & WB_STRIDE) != WB_STRIDE) &&
2571	    (first <= &tx_ring->tx_bi[i]) &&
2572	    (first >= &tx_ring->tx_bi[i & ~WB_STRIDE])) {
2573		tx_desc->cmd_type_offset_bsz =
2574			build_ctob(td_cmd, td_offset, size, td_tag) |
2575			cpu_to_le64((u64)I40E_TX_DESC_CMD_EOP <<
2576					 I40E_TXD_QW1_CMD_SHIFT);
2577	} else {
2578		tx_desc->cmd_type_offset_bsz =
2579			build_ctob(td_cmd, td_offset, size, td_tag) |
2580			cpu_to_le64((u64)I40E_TXD_CMD <<
2581					 I40E_TXD_QW1_CMD_SHIFT);
2582	}
2583
2584	netdev_tx_sent_queue(netdev_get_tx_queue(tx_ring->netdev,
2585						 tx_ring->queue_index),
2586			     first->bytecount);
2587
2588	/* set the timestamp */
2589	first->time_stamp = jiffies;
2590
2591	/* Force memory writes to complete before letting h/w
2592	 * know there are new descriptors to fetch.  (Only
2593	 * applicable for weak-ordered memory model archs,
2594	 * such as IA-64).
2595	 */
2596	wmb();
2597
2598	/* set next_to_watch value indicating a packet is present */
2599	first->next_to_watch = tx_desc;
2600
2601	i++;
2602	if (i == tx_ring->count)
2603		i = 0;
2604
2605	tx_ring->next_to_use = i;
2606
2607	i40e_maybe_stop_tx(tx_ring, DESC_NEEDED);
2608	/* notify HW of packet */
2609	if (!skb->xmit_more ||
2610	    netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
2611						   tx_ring->queue_index)))
2612		writel(i, tx_ring->tail);
2613
2614	return;
2615
2616dma_error:
2617	dev_info(tx_ring->dev, "TX DMA map failed\n");
2618
2619	/* clear dma mappings for failed tx_bi map */
2620	for (;;) {
2621		tx_bi = &tx_ring->tx_bi[i];
2622		i40e_unmap_and_free_tx_resource(tx_ring, tx_bi);
2623		if (tx_bi == first)
2624			break;
2625		if (i == 0)
2626			i = tx_ring->count;
2627		i--;
2628	}
2629
2630	tx_ring->next_to_use = i;
2631}
2632
2633/**
2634 * i40e_xmit_descriptor_count - calculate number of tx descriptors needed
2635 * @skb:     send buffer
2636 * @tx_ring: ring to send buffer on
2637 *
2638 * Returns number of data descriptors needed for this skb. Returns 0 to indicate
2639 * there is not enough descriptors available in this ring since we need at least
2640 * one descriptor.
2641 **/
2642#ifdef I40E_FCOE
2643int i40e_xmit_descriptor_count(struct sk_buff *skb,
2644			       struct i40e_ring *tx_ring)
2645#else
2646static int i40e_xmit_descriptor_count(struct sk_buff *skb,
2647				      struct i40e_ring *tx_ring)
2648#endif
2649{
2650	unsigned int f;
2651	int count = 0;
2652
2653	/* need: 1 descriptor per page * PAGE_SIZE/I40E_MAX_DATA_PER_TXD,
2654	 *       + 1 desc for skb_head_len/I40E_MAX_DATA_PER_TXD,
2655	 *       + 4 desc gap to avoid the cache line where head is,
2656	 *       + 1 desc for context descriptor,
2657	 * otherwise try next time
2658	 */
2659	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
2660		count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
2661
2662	count += TXD_USE_COUNT(skb_headlen(skb));
2663	if (i40e_maybe_stop_tx(tx_ring, count + 4 + 1)) {
2664		tx_ring->tx_stats.tx_busy++;
2665		return 0;
2666	}
2667	return count;
2668}
2669
2670/**
2671 * i40e_xmit_frame_ring - Sends buffer on Tx ring
2672 * @skb:     send buffer
2673 * @tx_ring: ring to send buffer on
2674 *
2675 * Returns NETDEV_TX_OK if sent, else an error code
2676 **/
2677static netdev_tx_t i40e_xmit_frame_ring(struct sk_buff *skb,
2678					struct i40e_ring *tx_ring)
2679{
2680	u64 cd_type_cmd_tso_mss = I40E_TX_DESC_DTYPE_CONTEXT;
2681	u32 cd_tunneling = 0, cd_l2tag2 = 0;
2682	struct i40e_tx_buffer *first;
2683	u32 td_offset = 0;
2684	u32 tx_flags = 0;
2685	__be16 protocol;
2686	u32 td_cmd = 0;
2687	u8 hdr_len = 0;
2688	int tsyn;
2689	int tso;
2690	if (0 == i40e_xmit_descriptor_count(skb, tx_ring))
2691		return NETDEV_TX_BUSY;
2692
2693	/* prepare the xmit flags */
2694	if (i40e_tx_prepare_vlan_flags(skb, tx_ring, &tx_flags))
2695		goto out_drop;
2696
2697	/* obtain protocol of skb */
2698	protocol = vlan_get_protocol(skb);
2699
2700	/* record the location of the first descriptor for this packet */
2701	first = &tx_ring->tx_bi[tx_ring->next_to_use];
2702
2703	/* setup IPv4/IPv6 offloads */
2704	if (protocol == htons(ETH_P_IP))
2705		tx_flags |= I40E_TX_FLAGS_IPV4;
2706	else if (protocol == htons(ETH_P_IPV6))
2707		tx_flags |= I40E_TX_FLAGS_IPV6;
2708
2709	tso = i40e_tso(tx_ring, skb, tx_flags, protocol, &hdr_len,
2710		       &cd_type_cmd_tso_mss, &cd_tunneling);
2711
2712	if (tso < 0)
2713		goto out_drop;
2714	else if (tso)
2715		tx_flags |= I40E_TX_FLAGS_TSO;
2716
2717	tsyn = i40e_tsyn(tx_ring, skb, tx_flags, &cd_type_cmd_tso_mss);
2718
2719	if (tsyn)
2720		tx_flags |= I40E_TX_FLAGS_TSYN;
2721
2722	if (i40e_chk_linearize(skb, tx_flags))
2723		if (skb_linearize(skb))
2724			goto out_drop;
2725
2726	skb_tx_timestamp(skb);
2727
2728	/* always enable CRC insertion offload */
2729	td_cmd |= I40E_TX_DESC_CMD_ICRC;
2730
2731	/* Always offload the checksum, since it's in the data descriptor */
2732	if (skb->ip_summed == CHECKSUM_PARTIAL) {
2733		tx_flags |= I40E_TX_FLAGS_CSUM;
2734
2735		i40e_tx_enable_csum(skb, tx_flags, &td_cmd, &td_offset,
2736				    tx_ring, &cd_tunneling);
2737	}
2738
2739	i40e_create_tx_ctx(tx_ring, cd_type_cmd_tso_mss,
2740			   cd_tunneling, cd_l2tag2);
2741
2742	/* Add Flow Director ATR if it's enabled.
2743	 *
2744	 * NOTE: this must always be directly before the data descriptor.
2745	 */
2746	i40e_atr(tx_ring, skb, tx_flags, protocol);
2747
2748	i40e_tx_map(tx_ring, skb, first, tx_flags, hdr_len,
2749		    td_cmd, td_offset);
2750
2751	return NETDEV_TX_OK;
2752
2753out_drop:
2754	dev_kfree_skb_any(skb);
2755	return NETDEV_TX_OK;
2756}
2757
2758/**
2759 * i40e_lan_xmit_frame - Selects the correct VSI and Tx queue to send buffer
2760 * @skb:    send buffer
2761 * @netdev: network interface device structure
2762 *
2763 * Returns NETDEV_TX_OK if sent, else an error code
2764 **/
2765netdev_tx_t i40e_lan_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
2766{
2767	struct i40e_netdev_priv *np = netdev_priv(netdev);
2768	struct i40e_vsi *vsi = np->vsi;
2769	struct i40e_ring *tx_ring = vsi->tx_rings[skb->queue_mapping];
2770
2771	/* hardware can't handle really short frames, hardware padding works
2772	 * beyond this point
2773	 */
2774	if (skb_put_padto(skb, I40E_MIN_TX_LEN))
2775		return NETDEV_TX_OK;
2776
2777	return i40e_xmit_frame_ring(skb, tx_ring);
2778}
2779