1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3	Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
4	Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
5	Copyright (C) 2004 - 2009 Gertjan van Wingerde <gwingerde@gmail.com>
6	<http://rt2x00.serialmonkey.com>
7
8 */
9
10/*
11	Module: rt2x00lib
12	Abstract: rt2x00 queue specific routines.
13 */
14
15#include <linux/slab.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/dma-mapping.h>
19
20#include "rt2x00.h"
21#include "rt2x00lib.h"
22
23struct sk_buff *rt2x00queue_alloc_rxskb(struct queue_entry *entry, gfp_t gfp)
24{
25	struct data_queue *queue = entry->queue;
26	struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
27	struct sk_buff *skb;
28	struct skb_frame_desc *skbdesc;
29	unsigned int frame_size;
30	unsigned int head_size = 0;
31	unsigned int tail_size = 0;
32
33	/*
34	 * The frame size includes descriptor size, because the
35	 * hardware directly receive the frame into the skbuffer.
36	 */
37	frame_size = queue->data_size + queue->desc_size + queue->winfo_size;
38
39	/*
40	 * The payload should be aligned to a 4-byte boundary,
41	 * this means we need at least 3 bytes for moving the frame
42	 * into the correct offset.
43	 */
44	head_size = 4;
45
46	/*
47	 * For IV/EIV/ICV assembly we must make sure there is
48	 * at least 8 bytes bytes available in headroom for IV/EIV
49	 * and 8 bytes for ICV data as tailroon.
50	 */
51	if (rt2x00_has_cap_hw_crypto(rt2x00dev)) {
52		head_size += 8;
53		tail_size += 8;
54	}
55
56	/*
57	 * Allocate skbuffer.
58	 */
59	skb = __dev_alloc_skb(frame_size + head_size + tail_size, gfp);
60	if (!skb)
61		return NULL;
62
63	/*
64	 * Make sure we not have a frame with the requested bytes
65	 * available in the head and tail.
66	 */
67	skb_reserve(skb, head_size);
68	skb_put(skb, frame_size);
69
70	/*
71	 * Populate skbdesc.
72	 */
73	skbdesc = get_skb_frame_desc(skb);
74	memset(skbdesc, 0, sizeof(*skbdesc));
75
76	if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_DMA)) {
77		dma_addr_t skb_dma;
78
79		skb_dma = dma_map_single(rt2x00dev->dev, skb->data, skb->len,
80					 DMA_FROM_DEVICE);
81		if (unlikely(dma_mapping_error(rt2x00dev->dev, skb_dma))) {
82			dev_kfree_skb_any(skb);
83			return NULL;
84		}
85
86		skbdesc->skb_dma = skb_dma;
87		skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
88	}
89
90	return skb;
91}
92
93int rt2x00queue_map_txskb(struct queue_entry *entry)
94{
95	struct device *dev = entry->queue->rt2x00dev->dev;
96	struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
97
98	skbdesc->skb_dma =
99	    dma_map_single(dev, entry->skb->data, entry->skb->len, DMA_TO_DEVICE);
100
101	if (unlikely(dma_mapping_error(dev, skbdesc->skb_dma)))
102		return -ENOMEM;
103
104	skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
105	rt2x00lib_dmadone(entry);
106	return 0;
107}
108EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
109
110void rt2x00queue_unmap_skb(struct queue_entry *entry)
111{
112	struct device *dev = entry->queue->rt2x00dev->dev;
113	struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
114
115	if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
116		dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len,
117				 DMA_FROM_DEVICE);
118		skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
119	} else if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
120		dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len,
121				 DMA_TO_DEVICE);
122		skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
123	}
124}
125EXPORT_SYMBOL_GPL(rt2x00queue_unmap_skb);
126
127void rt2x00queue_free_skb(struct queue_entry *entry)
128{
129	if (!entry->skb)
130		return;
131
132	rt2x00queue_unmap_skb(entry);
133	dev_kfree_skb_any(entry->skb);
134	entry->skb = NULL;
135}
136
137void rt2x00queue_align_frame(struct sk_buff *skb)
138{
139	unsigned int frame_length = skb->len;
140	unsigned int align = ALIGN_SIZE(skb, 0);
141
142	if (!align)
143		return;
144
145	skb_push(skb, align);
146	memmove(skb->data, skb->data + align, frame_length);
147	skb_trim(skb, frame_length);
148}
149
150/*
151 * H/W needs L2 padding between the header and the paylod if header size
152 * is not 4 bytes aligned.
153 */
154void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int hdr_len)
155{
156	unsigned int l2pad = (skb->len > hdr_len) ? L2PAD_SIZE(hdr_len) : 0;
157
158	if (!l2pad)
159		return;
160
161	skb_push(skb, l2pad);
162	memmove(skb->data, skb->data + l2pad, hdr_len);
163}
164
165void rt2x00queue_remove_l2pad(struct sk_buff *skb, unsigned int hdr_len)
166{
167	unsigned int l2pad = (skb->len > hdr_len) ? L2PAD_SIZE(hdr_len) : 0;
168
169	if (!l2pad)
170		return;
171
172	memmove(skb->data + l2pad, skb->data, hdr_len);
173	skb_pull(skb, l2pad);
174}
175
176static void rt2x00queue_create_tx_descriptor_seq(struct rt2x00_dev *rt2x00dev,
177						 struct sk_buff *skb,
178						 struct txentry_desc *txdesc)
179{
180	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
181	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
182	struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
183	u16 seqno;
184
185	if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
186		return;
187
188	__set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
189
190	if (!rt2x00_has_cap_flag(rt2x00dev, REQUIRE_SW_SEQNO)) {
191		/*
192		 * rt2800 has a H/W (or F/W) bug, device incorrectly increase
193		 * seqno on retransmitted data (non-QOS) and management frames.
194		 * To workaround the problem let's generate seqno in software.
195		 * Except for beacons which are transmitted periodically by H/W
196		 * hence hardware has to assign seqno for them.
197		 */
198	    	if (ieee80211_is_beacon(hdr->frame_control)) {
199			__set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
200			/* H/W will generate sequence number */
201			return;
202		}
203
204		__clear_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
205	}
206
207	/*
208	 * The hardware is not able to insert a sequence number. Assign a
209	 * software generated one here.
210	 *
211	 * This is wrong because beacons are not getting sequence
212	 * numbers assigned properly.
213	 *
214	 * A secondary problem exists for drivers that cannot toggle
215	 * sequence counting per-frame, since those will override the
216	 * sequence counter given by mac80211.
217	 */
218	if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
219		seqno = atomic_add_return(0x10, &intf->seqno);
220	else
221		seqno = atomic_read(&intf->seqno);
222
223	hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
224	hdr->seq_ctrl |= cpu_to_le16(seqno);
225}
226
227static void rt2x00queue_create_tx_descriptor_plcp(struct rt2x00_dev *rt2x00dev,
228						  struct sk_buff *skb,
229						  struct txentry_desc *txdesc,
230						  const struct rt2x00_rate *hwrate)
231{
232	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
233	struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
234	unsigned int data_length;
235	unsigned int duration;
236	unsigned int residual;
237
238	/*
239	 * Determine with what IFS priority this frame should be send.
240	 * Set ifs to IFS_SIFS when the this is not the first fragment,
241	 * or this fragment came after RTS/CTS.
242	 */
243	if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
244		txdesc->u.plcp.ifs = IFS_BACKOFF;
245	else
246		txdesc->u.plcp.ifs = IFS_SIFS;
247
248	/* Data length + CRC + Crypto overhead (IV/EIV/ICV/MIC) */
249	data_length = skb->len + 4;
250	data_length += rt2x00crypto_tx_overhead(rt2x00dev, skb);
251
252	/*
253	 * PLCP setup
254	 * Length calculation depends on OFDM/CCK rate.
255	 */
256	txdesc->u.plcp.signal = hwrate->plcp;
257	txdesc->u.plcp.service = 0x04;
258
259	if (hwrate->flags & DEV_RATE_OFDM) {
260		txdesc->u.plcp.length_high = (data_length >> 6) & 0x3f;
261		txdesc->u.plcp.length_low = data_length & 0x3f;
262	} else {
263		/*
264		 * Convert length to microseconds.
265		 */
266		residual = GET_DURATION_RES(data_length, hwrate->bitrate);
267		duration = GET_DURATION(data_length, hwrate->bitrate);
268
269		if (residual != 0) {
270			duration++;
271
272			/*
273			 * Check if we need to set the Length Extension
274			 */
275			if (hwrate->bitrate == 110 && residual <= 30)
276				txdesc->u.plcp.service |= 0x80;
277		}
278
279		txdesc->u.plcp.length_high = (duration >> 8) & 0xff;
280		txdesc->u.plcp.length_low = duration & 0xff;
281
282		/*
283		 * When preamble is enabled we should set the
284		 * preamble bit for the signal.
285		 */
286		if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
287			txdesc->u.plcp.signal |= 0x08;
288	}
289}
290
291static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev,
292						struct sk_buff *skb,
293						struct txentry_desc *txdesc,
294						struct ieee80211_sta *sta,
295						const struct rt2x00_rate *hwrate)
296{
297	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
298	struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
299	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
300	struct rt2x00_sta *sta_priv = NULL;
301	u8 density = 0;
302
303	if (sta) {
304		sta_priv = sta_to_rt2x00_sta(sta);
305		txdesc->u.ht.wcid = sta_priv->wcid;
306		density = sta->ht_cap.ampdu_density;
307	}
308
309	/*
310	 * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the
311	 * mcs rate to be used
312	 */
313	if (txrate->flags & IEEE80211_TX_RC_MCS) {
314		txdesc->u.ht.mcs = txrate->idx;
315
316		/*
317		 * MIMO PS should be set to 1 for STA's using dynamic SM PS
318		 * when using more then one tx stream (>MCS7).
319		 */
320		if (sta && txdesc->u.ht.mcs > 7 &&
321		    sta->smps_mode == IEEE80211_SMPS_DYNAMIC)
322			__set_bit(ENTRY_TXD_HT_MIMO_PS, &txdesc->flags);
323	} else {
324		txdesc->u.ht.mcs = rt2x00_get_rate_mcs(hwrate->mcs);
325		if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
326			txdesc->u.ht.mcs |= 0x08;
327	}
328
329	if (test_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags)) {
330		if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
331			txdesc->u.ht.txop = TXOP_SIFS;
332		else
333			txdesc->u.ht.txop = TXOP_BACKOFF;
334
335		/* Left zero on all other settings. */
336		return;
337	}
338
339	/*
340	 * Only one STBC stream is supported for now.
341	 */
342	if (tx_info->flags & IEEE80211_TX_CTL_STBC)
343		txdesc->u.ht.stbc = 1;
344
345	/*
346	 * This frame is eligible for an AMPDU, however, don't aggregate
347	 * frames that are intended to probe a specific tx rate.
348	 */
349	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU &&
350	    !(tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)) {
351		__set_bit(ENTRY_TXD_HT_AMPDU, &txdesc->flags);
352		txdesc->u.ht.mpdu_density = density;
353		txdesc->u.ht.ba_size = 7; /* FIXME: What value is needed? */
354	}
355
356	/*
357	 * Set 40Mhz mode if necessary (for legacy rates this will
358	 * duplicate the frame to both channels).
359	 */
360	if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH ||
361	    txrate->flags & IEEE80211_TX_RC_DUP_DATA)
362		__set_bit(ENTRY_TXD_HT_BW_40, &txdesc->flags);
363	if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
364		__set_bit(ENTRY_TXD_HT_SHORT_GI, &txdesc->flags);
365
366	/*
367	 * Determine IFS values
368	 * - Use TXOP_BACKOFF for management frames except beacons
369	 * - Use TXOP_SIFS for fragment bursts
370	 * - Use TXOP_HTTXOP for everything else
371	 *
372	 * Note: rt2800 devices won't use CTS protection (if used)
373	 * for frames not transmitted with TXOP_HTTXOP
374	 */
375	if (ieee80211_is_mgmt(hdr->frame_control) &&
376	    !ieee80211_is_beacon(hdr->frame_control))
377		txdesc->u.ht.txop = TXOP_BACKOFF;
378	else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT))
379		txdesc->u.ht.txop = TXOP_SIFS;
380	else
381		txdesc->u.ht.txop = TXOP_HTTXOP;
382}
383
384static void rt2x00queue_create_tx_descriptor(struct rt2x00_dev *rt2x00dev,
385					     struct sk_buff *skb,
386					     struct txentry_desc *txdesc,
387					     struct ieee80211_sta *sta)
388{
389	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
390	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
391	struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
392	struct ieee80211_rate *rate;
393	const struct rt2x00_rate *hwrate = NULL;
394
395	memset(txdesc, 0, sizeof(*txdesc));
396
397	/*
398	 * Header and frame information.
399	 */
400	txdesc->length = skb->len;
401	txdesc->header_length = ieee80211_get_hdrlen_from_skb(skb);
402
403	/*
404	 * Check whether this frame is to be acked.
405	 */
406	if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
407		__set_bit(ENTRY_TXD_ACK, &txdesc->flags);
408
409	/*
410	 * Check if this is a RTS/CTS frame
411	 */
412	if (ieee80211_is_rts(hdr->frame_control) ||
413	    ieee80211_is_cts(hdr->frame_control)) {
414		__set_bit(ENTRY_TXD_BURST, &txdesc->flags);
415		if (ieee80211_is_rts(hdr->frame_control))
416			__set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
417		else
418			__set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
419		if (tx_info->control.rts_cts_rate_idx >= 0)
420			rate =
421			    ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
422	}
423
424	/*
425	 * Determine retry information.
426	 */
427	txdesc->retry_limit = tx_info->control.rates[0].count - 1;
428	if (txdesc->retry_limit >= rt2x00dev->long_retry)
429		__set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
430
431	/*
432	 * Check if more fragments are pending
433	 */
434	if (ieee80211_has_morefrags(hdr->frame_control)) {
435		__set_bit(ENTRY_TXD_BURST, &txdesc->flags);
436		__set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
437	}
438
439	/*
440	 * Check if more frames (!= fragments) are pending
441	 */
442	if (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES)
443		__set_bit(ENTRY_TXD_BURST, &txdesc->flags);
444
445	/*
446	 * Beacons and probe responses require the tsf timestamp
447	 * to be inserted into the frame.
448	 */
449	if (ieee80211_is_beacon(hdr->frame_control) ||
450	    ieee80211_is_probe_resp(hdr->frame_control))
451		__set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
452
453	if ((tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) &&
454	    !test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags))
455		__set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
456
457	/*
458	 * Determine rate modulation.
459	 */
460	if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
461		txdesc->rate_mode = RATE_MODE_HT_GREENFIELD;
462	else if (txrate->flags & IEEE80211_TX_RC_MCS)
463		txdesc->rate_mode = RATE_MODE_HT_MIX;
464	else {
465		rate = ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
466		hwrate = rt2x00_get_rate(rate->hw_value);
467		if (hwrate->flags & DEV_RATE_OFDM)
468			txdesc->rate_mode = RATE_MODE_OFDM;
469		else
470			txdesc->rate_mode = RATE_MODE_CCK;
471	}
472
473	/*
474	 * Apply TX descriptor handling by components
475	 */
476	rt2x00crypto_create_tx_descriptor(rt2x00dev, skb, txdesc);
477	rt2x00queue_create_tx_descriptor_seq(rt2x00dev, skb, txdesc);
478
479	if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_HT_TX_DESC))
480		rt2x00queue_create_tx_descriptor_ht(rt2x00dev, skb, txdesc,
481						   sta, hwrate);
482	else
483		rt2x00queue_create_tx_descriptor_plcp(rt2x00dev, skb, txdesc,
484						      hwrate);
485}
486
487static int rt2x00queue_write_tx_data(struct queue_entry *entry,
488				     struct txentry_desc *txdesc)
489{
490	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
491
492	/*
493	 * This should not happen, we already checked the entry
494	 * was ours. When the hardware disagrees there has been
495	 * a queue corruption!
496	 */
497	if (unlikely(rt2x00dev->ops->lib->get_entry_state &&
498		     rt2x00dev->ops->lib->get_entry_state(entry))) {
499		rt2x00_err(rt2x00dev,
500			   "Corrupt queue %d, accessing entry which is not ours\n"
501			   "Please file bug report to %s\n",
502			   entry->queue->qid, DRV_PROJECT);
503		return -EINVAL;
504	}
505
506	/*
507	 * Add the requested extra tx headroom in front of the skb.
508	 */
509	skb_push(entry->skb, rt2x00dev->extra_tx_headroom);
510	memset(entry->skb->data, 0, rt2x00dev->extra_tx_headroom);
511
512	/*
513	 * Call the driver's write_tx_data function, if it exists.
514	 */
515	if (rt2x00dev->ops->lib->write_tx_data)
516		rt2x00dev->ops->lib->write_tx_data(entry, txdesc);
517
518	/*
519	 * Map the skb to DMA.
520	 */
521	if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_DMA) &&
522	    rt2x00queue_map_txskb(entry))
523		return -ENOMEM;
524
525	return 0;
526}
527
528static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
529					    struct txentry_desc *txdesc)
530{
531	struct data_queue *queue = entry->queue;
532
533	queue->rt2x00dev->ops->lib->write_tx_desc(entry, txdesc);
534
535	/*
536	 * All processing on the frame has been completed, this means
537	 * it is now ready to be dumped to userspace through debugfs.
538	 */
539	rt2x00debug_dump_frame(queue->rt2x00dev, DUMP_FRAME_TX, entry);
540}
541
542static void rt2x00queue_kick_tx_queue(struct data_queue *queue,
543				      struct txentry_desc *txdesc)
544{
545	/*
546	 * Check if we need to kick the queue, there are however a few rules
547	 *	1) Don't kick unless this is the last in frame in a burst.
548	 *	   When the burst flag is set, this frame is always followed
549	 *	   by another frame which in some way are related to eachother.
550	 *	   This is true for fragments, RTS or CTS-to-self frames.
551	 *	2) Rule 1 can be broken when the available entries
552	 *	   in the queue are less then a certain threshold.
553	 */
554	if (rt2x00queue_threshold(queue) ||
555	    !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
556		queue->rt2x00dev->ops->lib->kick_queue(queue);
557}
558
559static void rt2x00queue_bar_check(struct queue_entry *entry)
560{
561	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
562	struct ieee80211_bar *bar = (void *) (entry->skb->data +
563				    rt2x00dev->extra_tx_headroom);
564	struct rt2x00_bar_list_entry *bar_entry;
565
566	if (likely(!ieee80211_is_back_req(bar->frame_control)))
567		return;
568
569	bar_entry = kmalloc(sizeof(*bar_entry), GFP_ATOMIC);
570
571	/*
572	 * If the alloc fails we still send the BAR out but just don't track
573	 * it in our bar list. And as a result we will report it to mac80211
574	 * back as failed.
575	 */
576	if (!bar_entry)
577		return;
578
579	bar_entry->entry = entry;
580	bar_entry->block_acked = 0;
581
582	/*
583	 * Copy the relevant parts of the 802.11 BAR into out check list
584	 * such that we can use RCU for less-overhead in the RX path since
585	 * sending BARs and processing the according BlockAck should be
586	 * the exception.
587	 */
588	memcpy(bar_entry->ra, bar->ra, sizeof(bar->ra));
589	memcpy(bar_entry->ta, bar->ta, sizeof(bar->ta));
590	bar_entry->control = bar->control;
591	bar_entry->start_seq_num = bar->start_seq_num;
592
593	/*
594	 * Insert BAR into our BAR check list.
595	 */
596	spin_lock_bh(&rt2x00dev->bar_list_lock);
597	list_add_tail_rcu(&bar_entry->list, &rt2x00dev->bar_list);
598	spin_unlock_bh(&rt2x00dev->bar_list_lock);
599}
600
601int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb,
602			       struct ieee80211_sta *sta, bool local)
603{
604	struct ieee80211_tx_info *tx_info;
605	struct queue_entry *entry;
606	struct txentry_desc txdesc;
607	struct skb_frame_desc *skbdesc;
608	u8 rate_idx, rate_flags;
609	int ret = 0;
610
611	/*
612	 * Copy all TX descriptor information into txdesc,
613	 * after that we are free to use the skb->cb array
614	 * for our information.
615	 */
616	rt2x00queue_create_tx_descriptor(queue->rt2x00dev, skb, &txdesc, sta);
617
618	/*
619	 * All information is retrieved from the skb->cb array,
620	 * now we should claim ownership of the driver part of that
621	 * array, preserving the bitrate index and flags.
622	 */
623	tx_info = IEEE80211_SKB_CB(skb);
624	rate_idx = tx_info->control.rates[0].idx;
625	rate_flags = tx_info->control.rates[0].flags;
626	skbdesc = get_skb_frame_desc(skb);
627	memset(skbdesc, 0, sizeof(*skbdesc));
628	skbdesc->tx_rate_idx = rate_idx;
629	skbdesc->tx_rate_flags = rate_flags;
630
631	if (local)
632		skbdesc->flags |= SKBDESC_NOT_MAC80211;
633
634	/*
635	 * When hardware encryption is supported, and this frame
636	 * is to be encrypted, we should strip the IV/EIV data from
637	 * the frame so we can provide it to the driver separately.
638	 */
639	if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
640	    !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
641		if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_COPY_IV))
642			rt2x00crypto_tx_copy_iv(skb, &txdesc);
643		else
644			rt2x00crypto_tx_remove_iv(skb, &txdesc);
645	}
646
647	/*
648	 * When DMA allocation is required we should guarantee to the
649	 * driver that the DMA is aligned to a 4-byte boundary.
650	 * However some drivers require L2 padding to pad the payload
651	 * rather then the header. This could be a requirement for
652	 * PCI and USB devices, while header alignment only is valid
653	 * for PCI devices.
654	 */
655	if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_L2PAD))
656		rt2x00queue_insert_l2pad(skb, txdesc.header_length);
657	else if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_DMA))
658		rt2x00queue_align_frame(skb);
659
660	/*
661	 * That function must be called with bh disabled.
662	 */
663	spin_lock(&queue->tx_lock);
664
665	if (unlikely(rt2x00queue_full(queue))) {
666		rt2x00_dbg(queue->rt2x00dev, "Dropping frame due to full tx queue %d\n",
667			   queue->qid);
668		ret = -ENOBUFS;
669		goto out;
670	}
671
672	entry = rt2x00queue_get_entry(queue, Q_INDEX);
673
674	if (unlikely(test_and_set_bit(ENTRY_OWNER_DEVICE_DATA,
675				      &entry->flags))) {
676		rt2x00_err(queue->rt2x00dev,
677			   "Arrived at non-free entry in the non-full queue %d\n"
678			   "Please file bug report to %s\n",
679			   queue->qid, DRV_PROJECT);
680		ret = -EINVAL;
681		goto out;
682	}
683
684	entry->skb = skb;
685
686	/*
687	 * It could be possible that the queue was corrupted and this
688	 * call failed. Since we always return NETDEV_TX_OK to mac80211,
689	 * this frame will simply be dropped.
690	 */
691	if (unlikely(rt2x00queue_write_tx_data(entry, &txdesc))) {
692		clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
693		entry->skb = NULL;
694		ret = -EIO;
695		goto out;
696	}
697
698	/*
699	 * Put BlockAckReqs into our check list for driver BA processing.
700	 */
701	rt2x00queue_bar_check(entry);
702
703	set_bit(ENTRY_DATA_PENDING, &entry->flags);
704
705	rt2x00queue_index_inc(entry, Q_INDEX);
706	rt2x00queue_write_tx_descriptor(entry, &txdesc);
707	rt2x00queue_kick_tx_queue(queue, &txdesc);
708
709out:
710	/*
711	 * Pausing queue has to be serialized with rt2x00lib_txdone(), so we
712	 * do this under queue->tx_lock. Bottom halve was already disabled
713	 * before ieee80211_xmit() call.
714	 */
715	if (rt2x00queue_threshold(queue))
716		rt2x00queue_pause_queue(queue);
717
718	spin_unlock(&queue->tx_lock);
719	return ret;
720}
721
722int rt2x00queue_clear_beacon(struct rt2x00_dev *rt2x00dev,
723			     struct ieee80211_vif *vif)
724{
725	struct rt2x00_intf *intf = vif_to_intf(vif);
726
727	if (unlikely(!intf->beacon))
728		return -ENOBUFS;
729
730	/*
731	 * Clean up the beacon skb.
732	 */
733	rt2x00queue_free_skb(intf->beacon);
734
735	/*
736	 * Clear beacon (single bssid devices don't need to clear the beacon
737	 * since the beacon queue will get stopped anyway).
738	 */
739	if (rt2x00dev->ops->lib->clear_beacon)
740		rt2x00dev->ops->lib->clear_beacon(intf->beacon);
741
742	return 0;
743}
744
745int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
746			      struct ieee80211_vif *vif)
747{
748	struct rt2x00_intf *intf = vif_to_intf(vif);
749	struct skb_frame_desc *skbdesc;
750	struct txentry_desc txdesc;
751
752	if (unlikely(!intf->beacon))
753		return -ENOBUFS;
754
755	/*
756	 * Clean up the beacon skb.
757	 */
758	rt2x00queue_free_skb(intf->beacon);
759
760	intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
761	if (!intf->beacon->skb)
762		return -ENOMEM;
763
764	/*
765	 * Copy all TX descriptor information into txdesc,
766	 * after that we are free to use the skb->cb array
767	 * for our information.
768	 */
769	rt2x00queue_create_tx_descriptor(rt2x00dev, intf->beacon->skb, &txdesc, NULL);
770
771	/*
772	 * Fill in skb descriptor
773	 */
774	skbdesc = get_skb_frame_desc(intf->beacon->skb);
775	memset(skbdesc, 0, sizeof(*skbdesc));
776
777	/*
778	 * Send beacon to hardware.
779	 */
780	rt2x00dev->ops->lib->write_beacon(intf->beacon, &txdesc);
781
782	return 0;
783
784}
785
786bool rt2x00queue_for_each_entry(struct data_queue *queue,
787				enum queue_index start,
788				enum queue_index end,
789				void *data,
790				bool (*fn)(struct queue_entry *entry,
791					   void *data))
792{
793	unsigned long irqflags;
794	unsigned int index_start;
795	unsigned int index_end;
796	unsigned int i;
797
798	if (unlikely(start >= Q_INDEX_MAX || end >= Q_INDEX_MAX)) {
799		rt2x00_err(queue->rt2x00dev,
800			   "Entry requested from invalid index range (%d - %d)\n",
801			   start, end);
802		return true;
803	}
804
805	/*
806	 * Only protect the range we are going to loop over,
807	 * if during our loop a extra entry is set to pending
808	 * it should not be kicked during this run, since it
809	 * is part of another TX operation.
810	 */
811	spin_lock_irqsave(&queue->index_lock, irqflags);
812	index_start = queue->index[start];
813	index_end = queue->index[end];
814	spin_unlock_irqrestore(&queue->index_lock, irqflags);
815
816	/*
817	 * Start from the TX done pointer, this guarantees that we will
818	 * send out all frames in the correct order.
819	 */
820	if (index_start < index_end) {
821		for (i = index_start; i < index_end; i++) {
822			if (fn(&queue->entries[i], data))
823				return true;
824		}
825	} else {
826		for (i = index_start; i < queue->limit; i++) {
827			if (fn(&queue->entries[i], data))
828				return true;
829		}
830
831		for (i = 0; i < index_end; i++) {
832			if (fn(&queue->entries[i], data))
833				return true;
834		}
835	}
836
837	return false;
838}
839EXPORT_SYMBOL_GPL(rt2x00queue_for_each_entry);
840
841struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
842					  enum queue_index index)
843{
844	struct queue_entry *entry;
845	unsigned long irqflags;
846
847	if (unlikely(index >= Q_INDEX_MAX)) {
848		rt2x00_err(queue->rt2x00dev, "Entry requested from invalid index type (%d)\n",
849			   index);
850		return NULL;
851	}
852
853	spin_lock_irqsave(&queue->index_lock, irqflags);
854
855	entry = &queue->entries[queue->index[index]];
856
857	spin_unlock_irqrestore(&queue->index_lock, irqflags);
858
859	return entry;
860}
861EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
862
863void rt2x00queue_index_inc(struct queue_entry *entry, enum queue_index index)
864{
865	struct data_queue *queue = entry->queue;
866	unsigned long irqflags;
867
868	if (unlikely(index >= Q_INDEX_MAX)) {
869		rt2x00_err(queue->rt2x00dev,
870			   "Index change on invalid index type (%d)\n", index);
871		return;
872	}
873
874	spin_lock_irqsave(&queue->index_lock, irqflags);
875
876	queue->index[index]++;
877	if (queue->index[index] >= queue->limit)
878		queue->index[index] = 0;
879
880	entry->last_action = jiffies;
881
882	if (index == Q_INDEX) {
883		queue->length++;
884	} else if (index == Q_INDEX_DONE) {
885		queue->length--;
886		queue->count++;
887	}
888
889	spin_unlock_irqrestore(&queue->index_lock, irqflags);
890}
891
892static void rt2x00queue_pause_queue_nocheck(struct data_queue *queue)
893{
894	switch (queue->qid) {
895	case QID_AC_VO:
896	case QID_AC_VI:
897	case QID_AC_BE:
898	case QID_AC_BK:
899		/*
900		 * For TX queues, we have to disable the queue
901		 * inside mac80211.
902		 */
903		ieee80211_stop_queue(queue->rt2x00dev->hw, queue->qid);
904		break;
905	default:
906		break;
907	}
908}
909void rt2x00queue_pause_queue(struct data_queue *queue)
910{
911	if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
912	    !test_bit(QUEUE_STARTED, &queue->flags) ||
913	    test_and_set_bit(QUEUE_PAUSED, &queue->flags))
914		return;
915
916	rt2x00queue_pause_queue_nocheck(queue);
917}
918EXPORT_SYMBOL_GPL(rt2x00queue_pause_queue);
919
920void rt2x00queue_unpause_queue(struct data_queue *queue)
921{
922	if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
923	    !test_bit(QUEUE_STARTED, &queue->flags) ||
924	    !test_and_clear_bit(QUEUE_PAUSED, &queue->flags))
925		return;
926
927	switch (queue->qid) {
928	case QID_AC_VO:
929	case QID_AC_VI:
930	case QID_AC_BE:
931	case QID_AC_BK:
932		/*
933		 * For TX queues, we have to enable the queue
934		 * inside mac80211.
935		 */
936		ieee80211_wake_queue(queue->rt2x00dev->hw, queue->qid);
937		break;
938	case QID_RX:
939		/*
940		 * For RX we need to kick the queue now in order to
941		 * receive frames.
942		 */
943		queue->rt2x00dev->ops->lib->kick_queue(queue);
944	default:
945		break;
946	}
947}
948EXPORT_SYMBOL_GPL(rt2x00queue_unpause_queue);
949
950void rt2x00queue_start_queue(struct data_queue *queue)
951{
952	mutex_lock(&queue->status_lock);
953
954	if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
955	    test_and_set_bit(QUEUE_STARTED, &queue->flags)) {
956		mutex_unlock(&queue->status_lock);
957		return;
958	}
959
960	set_bit(QUEUE_PAUSED, &queue->flags);
961
962	queue->rt2x00dev->ops->lib->start_queue(queue);
963
964	rt2x00queue_unpause_queue(queue);
965
966	mutex_unlock(&queue->status_lock);
967}
968EXPORT_SYMBOL_GPL(rt2x00queue_start_queue);
969
970void rt2x00queue_stop_queue(struct data_queue *queue)
971{
972	mutex_lock(&queue->status_lock);
973
974	if (!test_and_clear_bit(QUEUE_STARTED, &queue->flags)) {
975		mutex_unlock(&queue->status_lock);
976		return;
977	}
978
979	rt2x00queue_pause_queue_nocheck(queue);
980
981	queue->rt2x00dev->ops->lib->stop_queue(queue);
982
983	mutex_unlock(&queue->status_lock);
984}
985EXPORT_SYMBOL_GPL(rt2x00queue_stop_queue);
986
987void rt2x00queue_flush_queue(struct data_queue *queue, bool drop)
988{
989	bool tx_queue =
990		(queue->qid == QID_AC_VO) ||
991		(queue->qid == QID_AC_VI) ||
992		(queue->qid == QID_AC_BE) ||
993		(queue->qid == QID_AC_BK);
994
995	if (rt2x00queue_empty(queue))
996		return;
997
998	/*
999	 * If we are not supposed to drop any pending
1000	 * frames, this means we must force a start (=kick)
1001	 * to the queue to make sure the hardware will
1002	 * start transmitting.
1003	 */
1004	if (!drop && tx_queue)
1005		queue->rt2x00dev->ops->lib->kick_queue(queue);
1006
1007	/*
1008	 * Check if driver supports flushing, if that is the case we can
1009	 * defer the flushing to the driver. Otherwise we must use the
1010	 * alternative which just waits for the queue to become empty.
1011	 */
1012	if (likely(queue->rt2x00dev->ops->lib->flush_queue))
1013		queue->rt2x00dev->ops->lib->flush_queue(queue, drop);
1014
1015	/*
1016	 * The queue flush has failed...
1017	 */
1018	if (unlikely(!rt2x00queue_empty(queue)))
1019		rt2x00_warn(queue->rt2x00dev, "Queue %d failed to flush\n",
1020			    queue->qid);
1021}
1022EXPORT_SYMBOL_GPL(rt2x00queue_flush_queue);
1023
1024void rt2x00queue_start_queues(struct rt2x00_dev *rt2x00dev)
1025{
1026	struct data_queue *queue;
1027
1028	/*
1029	 * rt2x00queue_start_queue will call ieee80211_wake_queue
1030	 * for each queue after is has been properly initialized.
1031	 */
1032	tx_queue_for_each(rt2x00dev, queue)
1033		rt2x00queue_start_queue(queue);
1034
1035	rt2x00queue_start_queue(rt2x00dev->rx);
1036}
1037EXPORT_SYMBOL_GPL(rt2x00queue_start_queues);
1038
1039void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev)
1040{
1041	struct data_queue *queue;
1042
1043	/*
1044	 * rt2x00queue_stop_queue will call ieee80211_stop_queue
1045	 * as well, but we are completely shutting doing everything
1046	 * now, so it is much safer to stop all TX queues at once,
1047	 * and use rt2x00queue_stop_queue for cleaning up.
1048	 */
1049	ieee80211_stop_queues(rt2x00dev->hw);
1050
1051	tx_queue_for_each(rt2x00dev, queue)
1052		rt2x00queue_stop_queue(queue);
1053
1054	rt2x00queue_stop_queue(rt2x00dev->rx);
1055}
1056EXPORT_SYMBOL_GPL(rt2x00queue_stop_queues);
1057
1058void rt2x00queue_flush_queues(struct rt2x00_dev *rt2x00dev, bool drop)
1059{
1060	struct data_queue *queue;
1061
1062	tx_queue_for_each(rt2x00dev, queue)
1063		rt2x00queue_flush_queue(queue, drop);
1064
1065	rt2x00queue_flush_queue(rt2x00dev->rx, drop);
1066}
1067EXPORT_SYMBOL_GPL(rt2x00queue_flush_queues);
1068
1069static void rt2x00queue_reset(struct data_queue *queue)
1070{
1071	unsigned long irqflags;
1072	unsigned int i;
1073
1074	spin_lock_irqsave(&queue->index_lock, irqflags);
1075
1076	queue->count = 0;
1077	queue->length = 0;
1078
1079	for (i = 0; i < Q_INDEX_MAX; i++)
1080		queue->index[i] = 0;
1081
1082	spin_unlock_irqrestore(&queue->index_lock, irqflags);
1083}
1084
1085void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
1086{
1087	struct data_queue *queue;
1088	unsigned int i;
1089
1090	queue_for_each(rt2x00dev, queue) {
1091		rt2x00queue_reset(queue);
1092
1093		for (i = 0; i < queue->limit; i++)
1094			rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
1095	}
1096}
1097
1098static int rt2x00queue_alloc_entries(struct data_queue *queue)
1099{
1100	struct queue_entry *entries;
1101	unsigned int entry_size;
1102	unsigned int i;
1103
1104	rt2x00queue_reset(queue);
1105
1106	/*
1107	 * Allocate all queue entries.
1108	 */
1109	entry_size = sizeof(*entries) + queue->priv_size;
1110	entries = kcalloc(queue->limit, entry_size, GFP_KERNEL);
1111	if (!entries)
1112		return -ENOMEM;
1113
1114#define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
1115	(((char *)(__base)) + ((__limit) * (__esize)) + \
1116	    ((__index) * (__psize)))
1117
1118	for (i = 0; i < queue->limit; i++) {
1119		entries[i].flags = 0;
1120		entries[i].queue = queue;
1121		entries[i].skb = NULL;
1122		entries[i].entry_idx = i;
1123		entries[i].priv_data =
1124		    QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
1125					    sizeof(*entries), queue->priv_size);
1126	}
1127
1128#undef QUEUE_ENTRY_PRIV_OFFSET
1129
1130	queue->entries = entries;
1131
1132	return 0;
1133}
1134
1135static void rt2x00queue_free_skbs(struct data_queue *queue)
1136{
1137	unsigned int i;
1138
1139	if (!queue->entries)
1140		return;
1141
1142	for (i = 0; i < queue->limit; i++) {
1143		rt2x00queue_free_skb(&queue->entries[i]);
1144	}
1145}
1146
1147static int rt2x00queue_alloc_rxskbs(struct data_queue *queue)
1148{
1149	unsigned int i;
1150	struct sk_buff *skb;
1151
1152	for (i = 0; i < queue->limit; i++) {
1153		skb = rt2x00queue_alloc_rxskb(&queue->entries[i], GFP_KERNEL);
1154		if (!skb)
1155			return -ENOMEM;
1156		queue->entries[i].skb = skb;
1157	}
1158
1159	return 0;
1160}
1161
1162int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
1163{
1164	struct data_queue *queue;
1165	int status;
1166
1167	status = rt2x00queue_alloc_entries(rt2x00dev->rx);
1168	if (status)
1169		goto exit;
1170
1171	tx_queue_for_each(rt2x00dev, queue) {
1172		status = rt2x00queue_alloc_entries(queue);
1173		if (status)
1174			goto exit;
1175	}
1176
1177	status = rt2x00queue_alloc_entries(rt2x00dev->bcn);
1178	if (status)
1179		goto exit;
1180
1181	if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_ATIM_QUEUE)) {
1182		status = rt2x00queue_alloc_entries(rt2x00dev->atim);
1183		if (status)
1184			goto exit;
1185	}
1186
1187	status = rt2x00queue_alloc_rxskbs(rt2x00dev->rx);
1188	if (status)
1189		goto exit;
1190
1191	return 0;
1192
1193exit:
1194	rt2x00_err(rt2x00dev, "Queue entries allocation failed\n");
1195
1196	rt2x00queue_uninitialize(rt2x00dev);
1197
1198	return status;
1199}
1200
1201void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
1202{
1203	struct data_queue *queue;
1204
1205	rt2x00queue_free_skbs(rt2x00dev->rx);
1206
1207	queue_for_each(rt2x00dev, queue) {
1208		kfree(queue->entries);
1209		queue->entries = NULL;
1210	}
1211}
1212
1213static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
1214			     struct data_queue *queue, enum data_queue_qid qid)
1215{
1216	mutex_init(&queue->status_lock);
1217	spin_lock_init(&queue->tx_lock);
1218	spin_lock_init(&queue->index_lock);
1219
1220	queue->rt2x00dev = rt2x00dev;
1221	queue->qid = qid;
1222	queue->txop = 0;
1223	queue->aifs = 2;
1224	queue->cw_min = 5;
1225	queue->cw_max = 10;
1226
1227	rt2x00dev->ops->queue_init(queue);
1228
1229	queue->threshold = DIV_ROUND_UP(queue->limit, 10);
1230}
1231
1232int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
1233{
1234	struct data_queue *queue;
1235	enum data_queue_qid qid;
1236	unsigned int req_atim =
1237	    rt2x00_has_cap_flag(rt2x00dev, REQUIRE_ATIM_QUEUE);
1238
1239	/*
1240	 * We need the following queues:
1241	 * RX: 1
1242	 * TX: ops->tx_queues
1243	 * Beacon: 1
1244	 * Atim: 1 (if required)
1245	 */
1246	rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
1247
1248	queue = kcalloc(rt2x00dev->data_queues, sizeof(*queue), GFP_KERNEL);
1249	if (!queue)
1250		return -ENOMEM;
1251
1252	/*
1253	 * Initialize pointers
1254	 */
1255	rt2x00dev->rx = queue;
1256	rt2x00dev->tx = &queue[1];
1257	rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
1258	rt2x00dev->atim = req_atim ? &queue[2 + rt2x00dev->ops->tx_queues] : NULL;
1259
1260	/*
1261	 * Initialize queue parameters.
1262	 * RX: qid = QID_RX
1263	 * TX: qid = QID_AC_VO + index
1264	 * TX: cw_min: 2^5 = 32.
1265	 * TX: cw_max: 2^10 = 1024.
1266	 * BCN: qid = QID_BEACON
1267	 * ATIM: qid = QID_ATIM
1268	 */
1269	rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
1270
1271	qid = QID_AC_VO;
1272	tx_queue_for_each(rt2x00dev, queue)
1273		rt2x00queue_init(rt2x00dev, queue, qid++);
1274
1275	rt2x00queue_init(rt2x00dev, rt2x00dev->bcn, QID_BEACON);
1276	if (req_atim)
1277		rt2x00queue_init(rt2x00dev, rt2x00dev->atim, QID_ATIM);
1278
1279	return 0;
1280}
1281
1282void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
1283{
1284	kfree(rt2x00dev->rx);
1285	rt2x00dev->rx = NULL;
1286	rt2x00dev->tx = NULL;
1287	rt2x00dev->bcn = NULL;
1288}
1289