[MAC80211]: Remove bitfields from struct ieee80211_sub_if_data
[wrt350n-kernel.git] / net / mac80211 / tx.c
blobddb104a70161a98a5f009e05a301eabbd72e2d60
1 /*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 * Transmit and frame generation functions.
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/skbuff.h>
18 #include <linux/etherdevice.h>
19 #include <linux/bitmap.h>
20 #include <net/ieee80211_radiotap.h>
21 #include <net/cfg80211.h>
22 #include <net/mac80211.h>
23 #include <asm/unaligned.h>
25 #include "ieee80211_i.h"
26 #include "ieee80211_led.h"
27 #include "wep.h"
28 #include "wpa.h"
29 #include "wme.h"
30 #include "ieee80211_rate.h"
32 #define IEEE80211_TX_OK 0
33 #define IEEE80211_TX_AGAIN 1
34 #define IEEE80211_TX_FRAG_AGAIN 2
36 /* misc utils */
38 static inline void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata,
39 struct ieee80211_hdr *hdr)
41 /* Set the sequence number for this frame. */
42 hdr->seq_ctrl = cpu_to_le16(sdata->sequence);
44 /* Increase the sequence number. */
45 sdata->sequence = (sdata->sequence + 0x10) & IEEE80211_SCTL_SEQ;
48 #ifdef CONFIG_MAC80211_LOWTX_FRAME_DUMP
49 static void ieee80211_dump_frame(const char *ifname, const char *title,
50 const struct sk_buff *skb)
52 const struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
53 u16 fc;
54 int hdrlen;
56 printk(KERN_DEBUG "%s: %s (len=%d)", ifname, title, skb->len);
57 if (skb->len < 4) {
58 printk("\n");
59 return;
62 fc = le16_to_cpu(hdr->frame_control);
63 hdrlen = ieee80211_get_hdrlen(fc);
64 if (hdrlen > skb->len)
65 hdrlen = skb->len;
66 if (hdrlen >= 4)
67 printk(" FC=0x%04x DUR=0x%04x",
68 fc, le16_to_cpu(hdr->duration_id));
69 if (hdrlen >= 10)
70 printk(" A1=" MAC_FMT, MAC_ARG(hdr->addr1));
71 if (hdrlen >= 16)
72 printk(" A2=" MAC_FMT, MAC_ARG(hdr->addr2));
73 if (hdrlen >= 24)
74 printk(" A3=" MAC_FMT, MAC_ARG(hdr->addr3));
75 if (hdrlen >= 30)
76 printk(" A4=" MAC_FMT, MAC_ARG(hdr->addr4));
77 printk("\n");
79 #else /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */
80 static inline void ieee80211_dump_frame(const char *ifname, const char *title,
81 struct sk_buff *skb)
84 #endif /* CONFIG_MAC80211_LOWTX_FRAME_DUMP */
86 static u16 ieee80211_duration(struct ieee80211_txrx_data *tx, int group_addr,
87 int next_frag_len)
89 int rate, mrate, erp, dur, i;
90 struct ieee80211_rate *txrate = tx->u.tx.rate;
91 struct ieee80211_local *local = tx->local;
92 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
94 erp = txrate->flags & IEEE80211_RATE_ERP;
97 * data and mgmt (except PS Poll):
98 * - during CFP: 32768
99 * - during contention period:
100 * if addr1 is group address: 0
101 * if more fragments = 0 and addr1 is individual address: time to
102 * transmit one ACK plus SIFS
103 * if more fragments = 1 and addr1 is individual address: time to
104 * transmit next fragment plus 2 x ACK plus 3 x SIFS
106 * IEEE 802.11, 9.6:
107 * - control response frame (CTS or ACK) shall be transmitted using the
108 * same rate as the immediately previous frame in the frame exchange
109 * sequence, if this rate belongs to the PHY mandatory rates, or else
110 * at the highest possible rate belonging to the PHY rates in the
111 * BSSBasicRateSet
114 if ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL) {
115 /* TODO: These control frames are not currently sent by
116 * 80211.o, but should they be implemented, this function
117 * needs to be updated to support duration field calculation.
119 * RTS: time needed to transmit pending data/mgmt frame plus
120 * one CTS frame plus one ACK frame plus 3 x SIFS
121 * CTS: duration of immediately previous RTS minus time
122 * required to transmit CTS and its SIFS
123 * ACK: 0 if immediately previous directed data/mgmt had
124 * more=0, with more=1 duration in ACK frame is duration
125 * from previous frame minus time needed to transmit ACK
126 * and its SIFS
127 * PS Poll: BIT(15) | BIT(14) | aid
129 return 0;
132 /* data/mgmt */
133 if (0 /* FIX: data/mgmt during CFP */)
134 return 32768;
136 if (group_addr) /* Group address as the destination - no ACK */
137 return 0;
139 /* Individual destination address:
140 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
141 * CTS and ACK frames shall be transmitted using the highest rate in
142 * basic rate set that is less than or equal to the rate of the
143 * immediately previous frame and that is using the same modulation
144 * (CCK or OFDM). If no basic rate set matches with these requirements,
145 * the highest mandatory rate of the PHY that is less than or equal to
146 * the rate of the previous frame is used.
147 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
149 rate = -1;
150 mrate = 10; /* use 1 Mbps if everything fails */
151 for (i = 0; i < mode->num_rates; i++) {
152 struct ieee80211_rate *r = &mode->rates[i];
153 if (r->rate > txrate->rate)
154 break;
156 if (IEEE80211_RATE_MODULATION(txrate->flags) !=
157 IEEE80211_RATE_MODULATION(r->flags))
158 continue;
160 if (r->flags & IEEE80211_RATE_BASIC)
161 rate = r->rate;
162 else if (r->flags & IEEE80211_RATE_MANDATORY)
163 mrate = r->rate;
165 if (rate == -1) {
166 /* No matching basic rate found; use highest suitable mandatory
167 * PHY rate */
168 rate = mrate;
171 /* Time needed to transmit ACK
172 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
173 * to closest integer */
175 dur = ieee80211_frame_duration(local, 10, rate, erp,
176 tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE);
178 if (next_frag_len) {
179 /* Frame is fragmented: duration increases with time needed to
180 * transmit next fragment plus ACK and 2 x SIFS. */
181 dur *= 2; /* ACK + SIFS */
182 /* next fragment */
183 dur += ieee80211_frame_duration(local, next_frag_len,
184 txrate->rate, erp,
185 tx->sdata->flags &
186 IEEE80211_SDATA_SHORT_PREAMBLE);
189 return dur;
192 static inline int __ieee80211_queue_stopped(const struct ieee80211_local *local,
193 int queue)
195 return test_bit(IEEE80211_LINK_STATE_XOFF, &local->state[queue]);
198 static inline int __ieee80211_queue_pending(const struct ieee80211_local *local,
199 int queue)
201 return test_bit(IEEE80211_LINK_STATE_PENDING, &local->state[queue]);
204 static int inline is_ieee80211_device(struct net_device *dev,
205 struct net_device *master)
207 return (wdev_priv(dev->ieee80211_ptr) ==
208 wdev_priv(master->ieee80211_ptr));
211 /* tx handlers */
213 static ieee80211_txrx_result
214 ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx)
216 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
217 struct sk_buff *skb = tx->skb;
218 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
219 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
220 u32 sta_flags;
222 if (unlikely(tx->local->sta_scanning != 0) &&
223 ((tx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
224 (tx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PROBE_REQ))
225 return TXRX_DROP;
227 if (tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED)
228 return TXRX_CONTINUE;
230 sta_flags = tx->sta ? tx->sta->flags : 0;
232 if (likely(tx->flags & IEEE80211_TXRXD_TXUNICAST)) {
233 if (unlikely(!(sta_flags & WLAN_STA_ASSOC) &&
234 tx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
235 (tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)) {
236 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
237 printk(KERN_DEBUG "%s: dropped data frame to not "
238 "associated station " MAC_FMT "\n",
239 tx->dev->name, MAC_ARG(hdr->addr1));
240 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
241 I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
242 return TXRX_DROP;
244 } else {
245 if (unlikely((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
246 tx->local->num_sta == 0 &&
247 tx->sdata->type != IEEE80211_IF_TYPE_IBSS)) {
249 * No associated STAs - no need to send multicast
250 * frames.
252 return TXRX_DROP;
254 return TXRX_CONTINUE;
257 if (unlikely(!tx->u.tx.mgmt_interface && tx->sdata->ieee802_1x &&
258 !(sta_flags & WLAN_STA_AUTHORIZED))) {
259 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
260 printk(KERN_DEBUG "%s: dropped frame to " MAC_FMT
261 " (unauthorized port)\n", tx->dev->name,
262 MAC_ARG(hdr->addr1));
263 #endif
264 I802_DEBUG_INC(tx->local->tx_handlers_drop_unauth_port);
265 return TXRX_DROP;
268 return TXRX_CONTINUE;
271 static ieee80211_txrx_result
272 ieee80211_tx_h_sequence(struct ieee80211_txrx_data *tx)
274 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
276 if (ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)) >= 24)
277 ieee80211_include_sequence(tx->sdata, hdr);
279 return TXRX_CONTINUE;
282 /* This function is called whenever the AP is about to exceed the maximum limit
283 * of buffered frames for power saving STAs. This situation should not really
284 * happen often during normal operation, so dropping the oldest buffered packet
285 * from each queue should be OK to make some room for new frames. */
286 static void purge_old_ps_buffers(struct ieee80211_local *local)
288 int total = 0, purged = 0;
289 struct sk_buff *skb;
290 struct ieee80211_sub_if_data *sdata;
291 struct sta_info *sta;
293 read_lock(&local->sub_if_lock);
294 list_for_each_entry(sdata, &local->sub_if_list, list) {
295 struct ieee80211_if_ap *ap;
296 if (sdata->dev == local->mdev ||
297 sdata->type != IEEE80211_IF_TYPE_AP)
298 continue;
299 ap = &sdata->u.ap;
300 skb = skb_dequeue(&ap->ps_bc_buf);
301 if (skb) {
302 purged++;
303 dev_kfree_skb(skb);
305 total += skb_queue_len(&ap->ps_bc_buf);
307 read_unlock(&local->sub_if_lock);
309 read_lock_bh(&local->sta_lock);
310 list_for_each_entry(sta, &local->sta_list, list) {
311 skb = skb_dequeue(&sta->ps_tx_buf);
312 if (skb) {
313 purged++;
314 dev_kfree_skb(skb);
316 total += skb_queue_len(&sta->ps_tx_buf);
318 read_unlock_bh(&local->sta_lock);
320 local->total_ps_buffered = total;
321 printk(KERN_DEBUG "%s: PS buffers full - purged %d frames\n",
322 local->mdev->name, purged);
325 static inline ieee80211_txrx_result
326 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_txrx_data *tx)
328 /* broadcast/multicast frame */
329 /* If any of the associated stations is in power save mode,
330 * the frame is buffered to be sent after DTIM beacon frame */
331 if ((tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING) &&
332 tx->sdata->type != IEEE80211_IF_TYPE_WDS &&
333 tx->sdata->bss && atomic_read(&tx->sdata->bss->num_sta_ps) &&
334 !(tx->fc & IEEE80211_FCTL_ORDER)) {
335 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
336 purge_old_ps_buffers(tx->local);
337 if (skb_queue_len(&tx->sdata->bss->ps_bc_buf) >=
338 AP_MAX_BC_BUFFER) {
339 if (net_ratelimit()) {
340 printk(KERN_DEBUG "%s: BC TX buffer full - "
341 "dropping the oldest frame\n",
342 tx->dev->name);
344 dev_kfree_skb(skb_dequeue(&tx->sdata->bss->ps_bc_buf));
345 } else
346 tx->local->total_ps_buffered++;
347 skb_queue_tail(&tx->sdata->bss->ps_bc_buf, tx->skb);
348 return TXRX_QUEUED;
351 return TXRX_CONTINUE;
354 static inline ieee80211_txrx_result
355 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_txrx_data *tx)
357 struct sta_info *sta = tx->sta;
359 if (unlikely(!sta ||
360 ((tx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
361 (tx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PROBE_RESP)))
362 return TXRX_CONTINUE;
364 if (unlikely((sta->flags & WLAN_STA_PS) && !sta->pspoll)) {
365 struct ieee80211_tx_packet_data *pkt_data;
366 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
367 printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS buffer (entries "
368 "before %d)\n",
369 MAC_ARG(sta->addr), sta->aid,
370 skb_queue_len(&sta->ps_tx_buf));
371 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
372 sta->flags |= WLAN_STA_TIM;
373 if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
374 purge_old_ps_buffers(tx->local);
375 if (skb_queue_len(&sta->ps_tx_buf) >= STA_MAX_TX_BUFFER) {
376 struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf);
377 if (net_ratelimit()) {
378 printk(KERN_DEBUG "%s: STA " MAC_FMT " TX "
379 "buffer full - dropping oldest frame\n",
380 tx->dev->name, MAC_ARG(sta->addr));
382 dev_kfree_skb(old);
383 } else
384 tx->local->total_ps_buffered++;
385 /* Queue frame to be sent after STA sends an PS Poll frame */
386 if (skb_queue_empty(&sta->ps_tx_buf)) {
387 if (tx->local->ops->set_tim)
388 tx->local->ops->set_tim(local_to_hw(tx->local),
389 sta->aid, 1);
390 if (tx->sdata->bss)
391 bss_tim_set(tx->local, tx->sdata->bss, sta->aid);
393 pkt_data = (struct ieee80211_tx_packet_data *)tx->skb->cb;
394 pkt_data->jiffies = jiffies;
395 skb_queue_tail(&sta->ps_tx_buf, tx->skb);
396 return TXRX_QUEUED;
398 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
399 else if (unlikely(sta->flags & WLAN_STA_PS)) {
400 printk(KERN_DEBUG "%s: STA " MAC_FMT " in PS mode, but pspoll "
401 "set -> send frame\n", tx->dev->name,
402 MAC_ARG(sta->addr));
404 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
405 sta->pspoll = 0;
407 return TXRX_CONTINUE;
411 static ieee80211_txrx_result
412 ieee80211_tx_h_ps_buf(struct ieee80211_txrx_data *tx)
414 if (unlikely(tx->flags & IEEE80211_TXRXD_TXPS_BUFFERED))
415 return TXRX_CONTINUE;
417 if (tx->flags & IEEE80211_TXRXD_TXUNICAST)
418 return ieee80211_tx_h_unicast_ps_buf(tx);
419 else
420 return ieee80211_tx_h_multicast_ps_buf(tx);
426 static ieee80211_txrx_result
427 ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
429 if (tx->sta)
430 tx->u.tx.control->key_idx = tx->sta->key_idx_compression;
431 else
432 tx->u.tx.control->key_idx = HW_KEY_IDX_INVALID;
434 if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
435 tx->key = NULL;
436 else if (tx->sta && tx->sta->key)
437 tx->key = tx->sta->key;
438 else if (tx->sdata->default_key)
439 tx->key = tx->sdata->default_key;
440 else if (tx->sdata->drop_unencrypted &&
441 !(tx->sdata->eapol && ieee80211_is_eapol(tx->skb))) {
442 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
443 return TXRX_DROP;
444 } else
445 tx->key = NULL;
447 if (tx->key) {
448 tx->key->tx_rx_count++;
449 if (unlikely(tx->local->key_tx_rx_threshold &&
450 tx->key->tx_rx_count >
451 tx->local->key_tx_rx_threshold)) {
452 ieee80211_key_threshold_notify(tx->dev, tx->key,
453 tx->sta);
457 return TXRX_CONTINUE;
460 static ieee80211_txrx_result
461 ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx)
463 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
464 size_t hdrlen, per_fragm, num_fragm, payload_len, left;
465 struct sk_buff **frags, *first, *frag;
466 int i;
467 u16 seq;
468 u8 *pos;
469 int frag_threshold = tx->local->fragmentation_threshold;
471 if (!(tx->flags & IEEE80211_TXRXD_FRAGMENTED))
472 return TXRX_CONTINUE;
474 first = tx->skb;
476 hdrlen = ieee80211_get_hdrlen(tx->fc);
477 payload_len = first->len - hdrlen;
478 per_fragm = frag_threshold - hdrlen - FCS_LEN;
479 num_fragm = DIV_ROUND_UP(payload_len, per_fragm);
481 frags = kzalloc(num_fragm * sizeof(struct sk_buff *), GFP_ATOMIC);
482 if (!frags)
483 goto fail;
485 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
486 seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ;
487 pos = first->data + hdrlen + per_fragm;
488 left = payload_len - per_fragm;
489 for (i = 0; i < num_fragm - 1; i++) {
490 struct ieee80211_hdr *fhdr;
491 size_t copylen;
493 if (left <= 0)
494 goto fail;
496 /* reserve enough extra head and tail room for possible
497 * encryption */
498 frag = frags[i] =
499 dev_alloc_skb(tx->local->tx_headroom +
500 frag_threshold +
501 IEEE80211_ENCRYPT_HEADROOM +
502 IEEE80211_ENCRYPT_TAILROOM);
503 if (!frag)
504 goto fail;
505 /* Make sure that all fragments use the same priority so
506 * that they end up using the same TX queue */
507 frag->priority = first->priority;
508 skb_reserve(frag, tx->local->tx_headroom +
509 IEEE80211_ENCRYPT_HEADROOM);
510 fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
511 memcpy(fhdr, first->data, hdrlen);
512 if (i == num_fragm - 2)
513 fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS);
514 fhdr->seq_ctrl = cpu_to_le16(seq | ((i + 1) & IEEE80211_SCTL_FRAG));
515 copylen = left > per_fragm ? per_fragm : left;
516 memcpy(skb_put(frag, copylen), pos, copylen);
518 pos += copylen;
519 left -= copylen;
521 skb_trim(first, hdrlen + per_fragm);
523 tx->u.tx.num_extra_frag = num_fragm - 1;
524 tx->u.tx.extra_frag = frags;
526 return TXRX_CONTINUE;
528 fail:
529 printk(KERN_DEBUG "%s: failed to fragment frame\n", tx->dev->name);
530 if (frags) {
531 for (i = 0; i < num_fragm - 1; i++)
532 if (frags[i])
533 dev_kfree_skb(frags[i]);
534 kfree(frags);
536 I802_DEBUG_INC(tx->local->tx_handlers_drop_fragment);
537 return TXRX_DROP;
540 static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
542 if (tx->key->force_sw_encrypt) {
543 if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
544 return -1;
545 } else {
546 tx->u.tx.control->key_idx = tx->key->hw_key_idx;
547 if (tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) {
548 if (ieee80211_wep_add_iv(tx->local, skb, tx->key) ==
549 NULL)
550 return -1;
553 return 0;
556 static ieee80211_txrx_result
557 ieee80211_tx_h_wep_encrypt(struct ieee80211_txrx_data *tx)
559 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
560 u16 fc;
562 fc = le16_to_cpu(hdr->frame_control);
564 if (!tx->key || tx->key->alg != ALG_WEP ||
565 ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
566 ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
567 (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
568 return TXRX_CONTINUE;
570 tx->u.tx.control->iv_len = WEP_IV_LEN;
571 tx->u.tx.control->icv_len = WEP_ICV_LEN;
572 ieee80211_tx_set_iswep(tx);
574 if (wep_encrypt_skb(tx, tx->skb) < 0) {
575 I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
576 return TXRX_DROP;
579 if (tx->u.tx.extra_frag) {
580 int i;
581 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
582 if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
583 I802_DEBUG_INC(tx->local->
584 tx_handlers_drop_wep);
585 return TXRX_DROP;
590 return TXRX_CONTINUE;
593 static ieee80211_txrx_result
594 ieee80211_tx_h_rate_ctrl(struct ieee80211_txrx_data *tx)
596 struct rate_control_extra extra;
598 memset(&extra, 0, sizeof(extra));
599 extra.mode = tx->u.tx.mode;
600 extra.mgmt_data = tx->sdata &&
601 tx->sdata->type == IEEE80211_IF_TYPE_MGMT;
602 extra.ethertype = tx->ethertype;
604 tx->u.tx.rate = rate_control_get_rate(tx->local, tx->dev, tx->skb,
605 &extra);
606 if (unlikely(extra.probe != NULL)) {
607 tx->u.tx.control->flags |= IEEE80211_TXCTL_RATE_CTRL_PROBE;
608 tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
609 tx->u.tx.control->alt_retry_rate = tx->u.tx.rate->val;
610 tx->u.tx.rate = extra.probe;
611 } else {
612 tx->u.tx.control->alt_retry_rate = -1;
614 if (!tx->u.tx.rate)
615 return TXRX_DROP;
616 if (tx->u.tx.mode->mode == MODE_IEEE80211G &&
617 (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
618 (tx->flags & IEEE80211_TXRXD_FRAGMENTED) && extra.nonerp) {
619 tx->u.tx.last_frag_rate = tx->u.tx.rate;
620 if (extra.probe)
621 tx->flags &= ~IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
622 else
623 tx->flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
624 tx->u.tx.rate = extra.nonerp;
625 tx->u.tx.control->rate = extra.nonerp;
626 tx->u.tx.control->flags &= ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
627 } else {
628 tx->u.tx.last_frag_rate = tx->u.tx.rate;
629 tx->u.tx.control->rate = tx->u.tx.rate;
631 tx->u.tx.control->tx_rate = tx->u.tx.rate->val;
633 return TXRX_CONTINUE;
636 static ieee80211_txrx_result
637 ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx)
639 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
640 u16 fc = le16_to_cpu(hdr->frame_control);
641 u16 dur;
642 struct ieee80211_tx_control *control = tx->u.tx.control;
643 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
645 if (!is_multicast_ether_addr(hdr->addr1)) {
646 if (tx->skb->len + FCS_LEN > tx->local->rts_threshold &&
647 tx->local->rts_threshold < IEEE80211_MAX_RTS_THRESHOLD) {
648 control->flags |= IEEE80211_TXCTL_USE_RTS_CTS;
649 control->flags |= IEEE80211_TXCTL_LONG_RETRY_LIMIT;
650 control->retry_limit =
651 tx->local->long_retry_limit;
652 } else {
653 control->retry_limit =
654 tx->local->short_retry_limit;
656 } else {
657 control->retry_limit = 1;
660 if (tx->flags & IEEE80211_TXRXD_FRAGMENTED) {
661 /* Do not use multiple retry rates when sending fragmented
662 * frames.
663 * TODO: The last fragment could still use multiple retry
664 * rates. */
665 control->alt_retry_rate = -1;
668 /* Use CTS protection for unicast frames sent using extended rates if
669 * there are associated non-ERP stations and RTS/CTS is not configured
670 * for the frame. */
671 if (mode->mode == MODE_IEEE80211G &&
672 (tx->u.tx.rate->flags & IEEE80211_RATE_ERP) &&
673 (tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
674 (tx->sdata->flags & IEEE80211_SDATA_USE_PROTECTION) &&
675 !(control->flags & IEEE80211_TXCTL_USE_RTS_CTS))
676 control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT;
678 /* Transmit data frames using short preambles if the driver supports
679 * short preambles at the selected rate and short preambles are
680 * available on the network at the current point in time. */
681 if (((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
682 (tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
683 (tx->sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
684 (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
685 tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
688 /* Setup duration field for the first fragment of the frame. Duration
689 * for remaining fragments will be updated when they are being sent
690 * to low-level driver in ieee80211_tx(). */
691 dur = ieee80211_duration(tx, is_multicast_ether_addr(hdr->addr1),
692 (tx->flags & IEEE80211_TXRXD_FRAGMENTED) ?
693 tx->u.tx.extra_frag[0]->len : 0);
694 hdr->duration_id = cpu_to_le16(dur);
696 if ((control->flags & IEEE80211_TXCTL_USE_RTS_CTS) ||
697 (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)) {
698 struct ieee80211_rate *rate;
700 /* Do not use multiple retry rates when using RTS/CTS */
701 control->alt_retry_rate = -1;
703 /* Use min(data rate, max base rate) as CTS/RTS rate */
704 rate = tx->u.tx.rate;
705 while (rate > mode->rates &&
706 !(rate->flags & IEEE80211_RATE_BASIC))
707 rate--;
709 control->rts_cts_rate = rate->val;
710 control->rts_rate = rate;
713 if (tx->sta) {
714 tx->sta->tx_packets++;
715 tx->sta->tx_fragments++;
716 tx->sta->tx_bytes += tx->skb->len;
717 if (tx->u.tx.extra_frag) {
718 int i;
719 tx->sta->tx_fragments += tx->u.tx.num_extra_frag;
720 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
721 tx->sta->tx_bytes +=
722 tx->u.tx.extra_frag[i]->len;
727 return TXRX_CONTINUE;
730 static ieee80211_txrx_result
731 ieee80211_tx_h_load_stats(struct ieee80211_txrx_data *tx)
733 struct ieee80211_local *local = tx->local;
734 struct ieee80211_hw_mode *mode = tx->u.tx.mode;
735 struct sk_buff *skb = tx->skb;
736 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
737 u32 load = 0, hdrtime;
739 /* TODO: this could be part of tx_status handling, so that the number
740 * of retries would be known; TX rate should in that case be stored
741 * somewhere with the packet */
743 /* Estimate total channel use caused by this frame */
745 /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
746 * 1 usec = 1/8 * (1080 / 10) = 13.5 */
748 if (mode->mode == MODE_IEEE80211A ||
749 mode->mode == MODE_ATHEROS_TURBO ||
750 mode->mode == MODE_ATHEROS_TURBOG ||
751 (mode->mode == MODE_IEEE80211G &&
752 tx->u.tx.rate->flags & IEEE80211_RATE_ERP))
753 hdrtime = CHAN_UTIL_HDR_SHORT;
754 else
755 hdrtime = CHAN_UTIL_HDR_LONG;
757 load = hdrtime;
758 if (!is_multicast_ether_addr(hdr->addr1))
759 load += hdrtime;
761 if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_RTS_CTS)
762 load += 2 * hdrtime;
763 else if (tx->u.tx.control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
764 load += hdrtime;
766 load += skb->len * tx->u.tx.rate->rate_inv;
768 if (tx->u.tx.extra_frag) {
769 int i;
770 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
771 load += 2 * hdrtime;
772 load += tx->u.tx.extra_frag[i]->len *
773 tx->u.tx.rate->rate;
777 /* Divide channel_use by 8 to avoid wrapping around the counter */
778 load >>= CHAN_UTIL_SHIFT;
779 local->channel_use_raw += load;
780 if (tx->sta)
781 tx->sta->channel_use_raw += load;
782 tx->sdata->channel_use_raw += load;
784 return TXRX_CONTINUE;
787 /* TODO: implement register/unregister functions for adding TX/RX handlers
788 * into ordered list */
790 ieee80211_tx_handler ieee80211_tx_handlers[] =
792 ieee80211_tx_h_check_assoc,
793 ieee80211_tx_h_sequence,
794 ieee80211_tx_h_ps_buf,
795 ieee80211_tx_h_select_key,
796 ieee80211_tx_h_michael_mic_add,
797 ieee80211_tx_h_fragment,
798 ieee80211_tx_h_tkip_encrypt,
799 ieee80211_tx_h_ccmp_encrypt,
800 ieee80211_tx_h_wep_encrypt,
801 ieee80211_tx_h_rate_ctrl,
802 ieee80211_tx_h_misc,
803 ieee80211_tx_h_load_stats,
804 NULL
807 /* actual transmit path */
810 * deal with packet injection down monitor interface
811 * with Radiotap Header -- only called for monitor mode interface
813 static ieee80211_txrx_result
814 __ieee80211_parse_tx_radiotap(
815 struct ieee80211_txrx_data *tx,
816 struct sk_buff *skb, struct ieee80211_tx_control *control)
819 * this is the moment to interpret and discard the radiotap header that
820 * must be at the start of the packet injected in Monitor mode
822 * Need to take some care with endian-ness since radiotap
823 * args are little-endian
826 struct ieee80211_radiotap_iterator iterator;
827 struct ieee80211_radiotap_header *rthdr =
828 (struct ieee80211_radiotap_header *) skb->data;
829 struct ieee80211_hw_mode *mode = tx->local->hw.conf.mode;
830 int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len);
833 * default control situation for all injected packets
834 * FIXME: this does not suit all usage cases, expand to allow control
837 control->retry_limit = 1; /* no retry */
838 control->key_idx = -1; /* no encryption key */
839 control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
840 IEEE80211_TXCTL_USE_CTS_PROTECT);
841 control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT |
842 IEEE80211_TXCTL_NO_ACK;
843 control->antenna_sel_tx = 0; /* default to default antenna */
846 * for every radiotap entry that is present
847 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
848 * entries present, or -EINVAL on error)
851 while (!ret) {
852 int i, target_rate;
854 ret = ieee80211_radiotap_iterator_next(&iterator);
856 if (ret)
857 continue;
859 /* see if this argument is something we can use */
860 switch (iterator.this_arg_index) {
862 * You must take care when dereferencing iterator.this_arg
863 * for multibyte types... the pointer is not aligned. Use
864 * get_unaligned((type *)iterator.this_arg) to dereference
865 * iterator.this_arg for type "type" safely on all arches.
867 case IEEE80211_RADIOTAP_RATE:
869 * radiotap rate u8 is in 500kbps units eg, 0x02=1Mbps
870 * ieee80211 rate int is in 100kbps units eg, 0x0a=1Mbps
872 target_rate = (*iterator.this_arg) * 5;
873 for (i = 0; i < mode->num_rates; i++) {
874 struct ieee80211_rate *r = &mode->rates[i];
876 if (r->rate > target_rate)
877 continue;
879 control->rate = r;
881 if (r->flags & IEEE80211_RATE_PREAMBLE2)
882 control->tx_rate = r->val2;
883 else
884 control->tx_rate = r->val;
886 /* end on exact match */
887 if (r->rate == target_rate)
888 i = mode->num_rates;
890 break;
892 case IEEE80211_RADIOTAP_ANTENNA:
894 * radiotap uses 0 for 1st ant, mac80211 is 1 for
895 * 1st ant
897 control->antenna_sel_tx = (*iterator.this_arg) + 1;
898 break;
900 case IEEE80211_RADIOTAP_DBM_TX_POWER:
901 control->power_level = *iterator.this_arg;
902 break;
904 case IEEE80211_RADIOTAP_FLAGS:
905 if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
907 * this indicates that the skb we have been
908 * handed has the 32-bit FCS CRC at the end...
909 * we should react to that by snipping it off
910 * because it will be recomputed and added
911 * on transmission
913 if (skb->len < (iterator.max_length + FCS_LEN))
914 return TXRX_DROP;
916 skb_trim(skb, skb->len - FCS_LEN);
918 break;
920 default:
921 break;
925 if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
926 return TXRX_DROP;
929 * remove the radiotap header
930 * iterator->max_length was sanity-checked against
931 * skb->len by iterator init
933 skb_pull(skb, iterator.max_length);
935 return TXRX_CONTINUE;
938 static ieee80211_txrx_result inline
939 __ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
940 struct sk_buff *skb,
941 struct net_device *dev,
942 struct ieee80211_tx_control *control)
944 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
945 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
946 struct ieee80211_sub_if_data *sdata;
947 ieee80211_txrx_result res = TXRX_CONTINUE;
949 int hdrlen;
951 memset(tx, 0, sizeof(*tx));
952 tx->skb = skb;
953 tx->dev = dev; /* use original interface */
954 tx->local = local;
955 tx->sdata = IEEE80211_DEV_TO_SUB_IF(dev);
956 tx->sta = sta_info_get(local, hdr->addr1);
957 tx->fc = le16_to_cpu(hdr->frame_control);
960 * set defaults for things that can be set by
961 * injected radiotap headers
963 control->power_level = local->hw.conf.power_level;
964 control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
966 /* process and remove the injection radiotap header */
967 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
968 if (unlikely(sdata->type == IEEE80211_IF_TYPE_MNTR)) {
969 if (__ieee80211_parse_tx_radiotap(tx, skb, control) ==
970 TXRX_DROP) {
971 return TXRX_DROP;
974 * we removed the radiotap header after this point,
975 * we filled control with what we could use
976 * set to the actual ieee header now
978 hdr = (struct ieee80211_hdr *) skb->data;
979 res = TXRX_QUEUED; /* indication it was monitor packet */
982 tx->u.tx.control = control;
983 if (is_multicast_ether_addr(hdr->addr1)) {
984 tx->flags &= ~IEEE80211_TXRXD_TXUNICAST;
985 control->flags |= IEEE80211_TXCTL_NO_ACK;
986 } else {
987 tx->flags |= IEEE80211_TXRXD_TXUNICAST;
988 control->flags &= ~IEEE80211_TXCTL_NO_ACK;
990 if (local->fragmentation_threshold < IEEE80211_MAX_FRAG_THRESHOLD &&
991 (tx->flags & IEEE80211_TXRXD_TXUNICAST) &&
992 skb->len + FCS_LEN > local->fragmentation_threshold &&
993 !local->ops->set_frag_threshold)
994 tx->flags |= IEEE80211_TXRXD_FRAGMENTED;
995 else
996 tx->flags &= ~IEEE80211_TXRXD_FRAGMENTED;
997 if (!tx->sta)
998 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
999 else if (tx->sta->clear_dst_mask) {
1000 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
1001 tx->sta->clear_dst_mask = 0;
1003 hdrlen = ieee80211_get_hdrlen(tx->fc);
1004 if (skb->len > hdrlen + sizeof(rfc1042_header) + 2) {
1005 u8 *pos = &skb->data[hdrlen + sizeof(rfc1042_header)];
1006 tx->ethertype = (pos[0] << 8) | pos[1];
1008 control->flags |= IEEE80211_TXCTL_FIRST_FRAGMENT;
1010 return res;
1013 /* Device in tx->dev has a reference added; use dev_put(tx->dev) when
1014 * finished with it. */
1015 static int inline ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
1016 struct sk_buff *skb,
1017 struct net_device *mdev,
1018 struct ieee80211_tx_control *control)
1020 struct ieee80211_tx_packet_data *pkt_data;
1021 struct net_device *dev;
1023 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1024 dev = dev_get_by_index(pkt_data->ifindex);
1025 if (unlikely(dev && !is_ieee80211_device(dev, mdev))) {
1026 dev_put(dev);
1027 dev = NULL;
1029 if (unlikely(!dev))
1030 return -ENODEV;
1031 __ieee80211_tx_prepare(tx, skb, dev, control);
1032 return 0;
1035 static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb,
1036 struct ieee80211_txrx_data *tx)
1038 struct ieee80211_tx_control *control = tx->u.tx.control;
1039 int ret, i;
1041 if (!ieee80211_qdisc_installed(local->mdev) &&
1042 __ieee80211_queue_stopped(local, 0)) {
1043 netif_stop_queue(local->mdev);
1044 return IEEE80211_TX_AGAIN;
1046 if (skb) {
1047 ieee80211_dump_frame(local->mdev->name, "TX to low-level driver", skb);
1048 ret = local->ops->tx(local_to_hw(local), skb, control);
1049 if (ret)
1050 return IEEE80211_TX_AGAIN;
1051 local->mdev->trans_start = jiffies;
1052 ieee80211_led_tx(local, 1);
1054 if (tx->u.tx.extra_frag) {
1055 control->flags &= ~(IEEE80211_TXCTL_USE_RTS_CTS |
1056 IEEE80211_TXCTL_USE_CTS_PROTECT |
1057 IEEE80211_TXCTL_CLEAR_DST_MASK |
1058 IEEE80211_TXCTL_FIRST_FRAGMENT);
1059 for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
1060 if (!tx->u.tx.extra_frag[i])
1061 continue;
1062 if (__ieee80211_queue_stopped(local, control->queue))
1063 return IEEE80211_TX_FRAG_AGAIN;
1064 if (i == tx->u.tx.num_extra_frag) {
1065 control->tx_rate = tx->u.tx.last_frag_hwrate;
1066 control->rate = tx->u.tx.last_frag_rate;
1067 if (tx->flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG)
1068 control->flags |=
1069 IEEE80211_TXCTL_RATE_CTRL_PROBE;
1070 else
1071 control->flags &=
1072 ~IEEE80211_TXCTL_RATE_CTRL_PROBE;
1075 ieee80211_dump_frame(local->mdev->name,
1076 "TX to low-level driver",
1077 tx->u.tx.extra_frag[i]);
1078 ret = local->ops->tx(local_to_hw(local),
1079 tx->u.tx.extra_frag[i],
1080 control);
1081 if (ret)
1082 return IEEE80211_TX_FRAG_AGAIN;
1083 local->mdev->trans_start = jiffies;
1084 ieee80211_led_tx(local, 1);
1085 tx->u.tx.extra_frag[i] = NULL;
1087 kfree(tx->u.tx.extra_frag);
1088 tx->u.tx.extra_frag = NULL;
1090 return IEEE80211_TX_OK;
1093 static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
1094 struct ieee80211_tx_control *control, int mgmt)
1096 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1097 struct sta_info *sta;
1098 ieee80211_tx_handler *handler;
1099 struct ieee80211_txrx_data tx;
1100 ieee80211_txrx_result res = TXRX_DROP, res_prepare;
1101 int ret, i;
1103 WARN_ON(__ieee80211_queue_pending(local, control->queue));
1105 if (unlikely(skb->len < 10)) {
1106 dev_kfree_skb(skb);
1107 return 0;
1110 res_prepare = __ieee80211_tx_prepare(&tx, skb, dev, control);
1112 if (res_prepare == TXRX_DROP) {
1113 dev_kfree_skb(skb);
1114 return 0;
1117 sta = tx.sta;
1118 tx.u.tx.mgmt_interface = mgmt;
1119 tx.u.tx.mode = local->hw.conf.mode;
1121 if (res_prepare == TXRX_QUEUED) { /* if it was an injected packet */
1122 res = TXRX_CONTINUE;
1123 } else {
1124 for (handler = local->tx_handlers; *handler != NULL;
1125 handler++) {
1126 res = (*handler)(&tx);
1127 if (res != TXRX_CONTINUE)
1128 break;
1132 skb = tx.skb; /* handlers are allowed to change skb */
1134 if (sta)
1135 sta_info_put(sta);
1137 if (unlikely(res == TXRX_DROP)) {
1138 I802_DEBUG_INC(local->tx_handlers_drop);
1139 goto drop;
1142 if (unlikely(res == TXRX_QUEUED)) {
1143 I802_DEBUG_INC(local->tx_handlers_queued);
1144 return 0;
1147 if (tx.u.tx.extra_frag) {
1148 for (i = 0; i < tx.u.tx.num_extra_frag; i++) {
1149 int next_len, dur;
1150 struct ieee80211_hdr *hdr =
1151 (struct ieee80211_hdr *)
1152 tx.u.tx.extra_frag[i]->data;
1154 if (i + 1 < tx.u.tx.num_extra_frag) {
1155 next_len = tx.u.tx.extra_frag[i + 1]->len;
1156 } else {
1157 next_len = 0;
1158 tx.u.tx.rate = tx.u.tx.last_frag_rate;
1159 tx.u.tx.last_frag_hwrate = tx.u.tx.rate->val;
1161 dur = ieee80211_duration(&tx, 0, next_len);
1162 hdr->duration_id = cpu_to_le16(dur);
1166 retry:
1167 ret = __ieee80211_tx(local, skb, &tx);
1168 if (ret) {
1169 struct ieee80211_tx_stored_packet *store =
1170 &local->pending_packet[control->queue];
1172 if (ret == IEEE80211_TX_FRAG_AGAIN)
1173 skb = NULL;
1174 set_bit(IEEE80211_LINK_STATE_PENDING,
1175 &local->state[control->queue]);
1176 smp_mb();
1177 /* When the driver gets out of buffers during sending of
1178 * fragments and calls ieee80211_stop_queue, there is
1179 * a small window between IEEE80211_LINK_STATE_XOFF and
1180 * IEEE80211_LINK_STATE_PENDING flags are set. If a buffer
1181 * gets available in that window (i.e. driver calls
1182 * ieee80211_wake_queue), we would end up with ieee80211_tx
1183 * called with IEEE80211_LINK_STATE_PENDING. Prevent this by
1184 * continuing transmitting here when that situation is
1185 * possible to have happened. */
1186 if (!__ieee80211_queue_stopped(local, control->queue)) {
1187 clear_bit(IEEE80211_LINK_STATE_PENDING,
1188 &local->state[control->queue]);
1189 goto retry;
1191 memcpy(&store->control, control,
1192 sizeof(struct ieee80211_tx_control));
1193 store->skb = skb;
1194 store->extra_frag = tx.u.tx.extra_frag;
1195 store->num_extra_frag = tx.u.tx.num_extra_frag;
1196 store->last_frag_hwrate = tx.u.tx.last_frag_hwrate;
1197 store->last_frag_rate = tx.u.tx.last_frag_rate;
1198 store->last_frag_rate_ctrl_probe =
1199 !!(tx.flags & IEEE80211_TXRXD_TXPROBE_LAST_FRAG);
1201 return 0;
1203 drop:
1204 if (skb)
1205 dev_kfree_skb(skb);
1206 for (i = 0; i < tx.u.tx.num_extra_frag; i++)
1207 if (tx.u.tx.extra_frag[i])
1208 dev_kfree_skb(tx.u.tx.extra_frag[i]);
1209 kfree(tx.u.tx.extra_frag);
1210 return 0;
1213 /* device xmit handlers */
1215 int ieee80211_master_start_xmit(struct sk_buff *skb,
1216 struct net_device *dev)
1218 struct ieee80211_tx_control control;
1219 struct ieee80211_tx_packet_data *pkt_data;
1220 struct net_device *odev = NULL;
1221 struct ieee80211_sub_if_data *osdata;
1222 int headroom;
1223 int ret;
1226 * copy control out of the skb so other people can use skb->cb
1228 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1229 memset(&control, 0, sizeof(struct ieee80211_tx_control));
1231 if (pkt_data->ifindex)
1232 odev = dev_get_by_index(pkt_data->ifindex);
1233 if (unlikely(odev && !is_ieee80211_device(odev, dev))) {
1234 dev_put(odev);
1235 odev = NULL;
1237 if (unlikely(!odev)) {
1238 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1239 printk(KERN_DEBUG "%s: Discarded packet with nonexistent "
1240 "originating device\n", dev->name);
1241 #endif
1242 dev_kfree_skb(skb);
1243 return 0;
1245 osdata = IEEE80211_DEV_TO_SUB_IF(odev);
1247 headroom = osdata->local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM;
1248 if (skb_headroom(skb) < headroom) {
1249 if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
1250 dev_kfree_skb(skb);
1251 dev_put(odev);
1252 return 0;
1256 control.ifindex = odev->ifindex;
1257 control.type = osdata->type;
1258 if (pkt_data->flags & IEEE80211_TXPD_REQ_TX_STATUS)
1259 control.flags |= IEEE80211_TXCTL_REQ_TX_STATUS;
1260 if (pkt_data->flags & IEEE80211_TXPD_DO_NOT_ENCRYPT)
1261 control.flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
1262 if (pkt_data->flags & IEEE80211_TXPD_REQUEUE)
1263 control.flags |= IEEE80211_TXCTL_REQUEUE;
1264 control.queue = pkt_data->queue;
1266 ret = ieee80211_tx(odev, skb, &control,
1267 control.type == IEEE80211_IF_TYPE_MGMT);
1268 dev_put(odev);
1270 return ret;
1273 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
1274 struct net_device *dev)
1276 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1277 struct ieee80211_tx_packet_data *pkt_data;
1278 struct ieee80211_radiotap_header *prthdr =
1279 (struct ieee80211_radiotap_header *)skb->data;
1280 u16 len_rthdr;
1282 /* check for not even having the fixed radiotap header part */
1283 if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1284 goto fail; /* too short to be possibly valid */
1286 /* is it a header version we can trust to find length from? */
1287 if (unlikely(prthdr->it_version))
1288 goto fail; /* only version 0 is supported */
1290 /* then there must be a radiotap header with a length we can use */
1291 len_rthdr = ieee80211_get_radiotap_len(skb->data);
1293 /* does the skb contain enough to deliver on the alleged length? */
1294 if (unlikely(skb->len < len_rthdr))
1295 goto fail; /* skb too short for claimed rt header extent */
1297 skb->dev = local->mdev;
1299 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1300 memset(pkt_data, 0, sizeof(*pkt_data));
1301 /* needed because we set skb device to master */
1302 pkt_data->ifindex = dev->ifindex;
1304 pkt_data->flags |= IEEE80211_TXPD_DO_NOT_ENCRYPT;
1307 * fix up the pointers accounting for the radiotap
1308 * header still being in there. We are being given
1309 * a precooked IEEE80211 header so no need for
1310 * normal processing
1312 skb_set_mac_header(skb, len_rthdr);
1314 * these are just fixed to the end of the rt area since we
1315 * don't have any better information and at this point, nobody cares
1317 skb_set_network_header(skb, len_rthdr);
1318 skb_set_transport_header(skb, len_rthdr);
1320 /* pass the radiotap header up to the next stage intact */
1321 dev_queue_xmit(skb);
1322 return NETDEV_TX_OK;
1324 fail:
1325 dev_kfree_skb(skb);
1326 return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1330 * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1331 * subinterfaces (wlan#, WDS, and VLAN interfaces)
1332 * @skb: packet to be sent
1333 * @dev: incoming interface
1335 * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1336 * not be freed, and caller is responsible for either retrying later or freeing
1337 * skb).
1339 * This function takes in an Ethernet header and encapsulates it with suitable
1340 * IEEE 802.11 header based on which interface the packet is coming in. The
1341 * encapsulated packet will then be passed to master interface, wlan#.11, for
1342 * transmission (through low-level driver).
1344 int ieee80211_subif_start_xmit(struct sk_buff *skb,
1345 struct net_device *dev)
1347 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1348 struct ieee80211_tx_packet_data *pkt_data;
1349 struct ieee80211_sub_if_data *sdata;
1350 int ret = 1, head_need;
1351 u16 ethertype, hdrlen, fc;
1352 struct ieee80211_hdr hdr;
1353 const u8 *encaps_data;
1354 int encaps_len, skip_header_bytes;
1355 int nh_pos, h_pos;
1356 struct sta_info *sta;
1358 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1359 if (unlikely(skb->len < ETH_HLEN)) {
1360 printk(KERN_DEBUG "%s: short skb (len=%d)\n",
1361 dev->name, skb->len);
1362 ret = 0;
1363 goto fail;
1366 nh_pos = skb_network_header(skb) - skb->data;
1367 h_pos = skb_transport_header(skb) - skb->data;
1369 /* convert Ethernet header to proper 802.11 header (based on
1370 * operation mode) */
1371 ethertype = (skb->data[12] << 8) | skb->data[13];
1372 /* TODO: handling for 802.1x authorized/unauthorized port */
1373 fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
1375 switch (sdata->type) {
1376 case IEEE80211_IF_TYPE_AP:
1377 case IEEE80211_IF_TYPE_VLAN:
1378 fc |= IEEE80211_FCTL_FROMDS;
1379 /* DA BSSID SA */
1380 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1381 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1382 memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1383 hdrlen = 24;
1384 break;
1385 case IEEE80211_IF_TYPE_WDS:
1386 fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
1387 /* RA TA DA SA */
1388 memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1389 memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
1390 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1391 memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1392 hdrlen = 30;
1393 break;
1394 case IEEE80211_IF_TYPE_STA:
1395 fc |= IEEE80211_FCTL_TODS;
1396 /* BSSID SA DA */
1397 memcpy(hdr.addr1, sdata->u.sta.bssid, ETH_ALEN);
1398 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1399 memcpy(hdr.addr3, skb->data, ETH_ALEN);
1400 hdrlen = 24;
1401 break;
1402 case IEEE80211_IF_TYPE_IBSS:
1403 /* DA SA BSSID */
1404 memcpy(hdr.addr1, skb->data, ETH_ALEN);
1405 memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1406 memcpy(hdr.addr3, sdata->u.sta.bssid, ETH_ALEN);
1407 hdrlen = 24;
1408 break;
1409 default:
1410 ret = 0;
1411 goto fail;
1414 /* receiver is QoS enabled, use a QoS type frame */
1415 sta = sta_info_get(local, hdr.addr1);
1416 if (sta) {
1417 if (sta->flags & WLAN_STA_WME) {
1418 fc |= IEEE80211_STYPE_QOS_DATA;
1419 hdrlen += 2;
1421 sta_info_put(sta);
1424 hdr.frame_control = cpu_to_le16(fc);
1425 hdr.duration_id = 0;
1426 hdr.seq_ctrl = 0;
1428 skip_header_bytes = ETH_HLEN;
1429 if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
1430 encaps_data = bridge_tunnel_header;
1431 encaps_len = sizeof(bridge_tunnel_header);
1432 skip_header_bytes -= 2;
1433 } else if (ethertype >= 0x600) {
1434 encaps_data = rfc1042_header;
1435 encaps_len = sizeof(rfc1042_header);
1436 skip_header_bytes -= 2;
1437 } else {
1438 encaps_data = NULL;
1439 encaps_len = 0;
1442 skb_pull(skb, skip_header_bytes);
1443 nh_pos -= skip_header_bytes;
1444 h_pos -= skip_header_bytes;
1446 /* TODO: implement support for fragments so that there is no need to
1447 * reallocate and copy payload; it might be enough to support one
1448 * extra fragment that would be copied in the beginning of the frame
1449 * data.. anyway, it would be nice to include this into skb structure
1450 * somehow
1452 * There are few options for this:
1453 * use skb->cb as an extra space for 802.11 header
1454 * allocate new buffer if not enough headroom
1455 * make sure that there is enough headroom in every skb by increasing
1456 * build in headroom in __dev_alloc_skb() (linux/skbuff.h) and
1457 * alloc_skb() (net/core/skbuff.c)
1459 head_need = hdrlen + encaps_len + local->tx_headroom;
1460 head_need -= skb_headroom(skb);
1462 /* We are going to modify skb data, so make a copy of it if happens to
1463 * be cloned. This could happen, e.g., with Linux bridge code passing
1464 * us broadcast frames. */
1466 if (head_need > 0 || skb_cloned(skb)) {
1467 #if 0
1468 printk(KERN_DEBUG "%s: need to reallocate buffer for %d bytes "
1469 "of headroom\n", dev->name, head_need);
1470 #endif
1472 if (skb_cloned(skb))
1473 I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1474 else
1475 I802_DEBUG_INC(local->tx_expand_skb_head);
1476 /* Since we have to reallocate the buffer, make sure that there
1477 * is enough room for possible WEP IV/ICV and TKIP (8 bytes
1478 * before payload and 12 after). */
1479 if (pskb_expand_head(skb, (head_need > 0 ? head_need + 8 : 8),
1480 12, GFP_ATOMIC)) {
1481 printk(KERN_DEBUG "%s: failed to reallocate TX buffer"
1482 "\n", dev->name);
1483 goto fail;
1487 if (encaps_data) {
1488 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
1489 nh_pos += encaps_len;
1490 h_pos += encaps_len;
1492 memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
1493 nh_pos += hdrlen;
1494 h_pos += hdrlen;
1496 pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
1497 memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
1498 pkt_data->ifindex = dev->ifindex;
1499 if (sdata->type == IEEE80211_IF_TYPE_MGMT)
1500 pkt_data->flags |= IEEE80211_TXPD_MGMT_IFACE;
1502 skb->dev = local->mdev;
1503 sdata->stats.tx_packets++;
1504 sdata->stats.tx_bytes += skb->len;
1506 /* Update skb pointers to various headers since this modified frame
1507 * is going to go through Linux networking code that may potentially
1508 * need things like pointer to IP header. */
1509 skb_set_mac_header(skb, 0);
1510 skb_set_network_header(skb, nh_pos);
1511 skb_set_transport_header(skb, h_pos);
1513 dev->trans_start = jiffies;
1514 dev_queue_xmit(skb);
1516 return 0;
1518 fail:
1519 if (!ret)
1520 dev_kfree_skb(skb);
1522 return ret;
1526 * This is the transmit routine for the 802.11 type interfaces
1527 * called by upper layers of the linux networking
1528 * stack when it has a frame to transmit
1530 int ieee80211_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev)
1532 struct ieee80211_sub_if_data *sdata;
1533 struct ieee80211_tx_packet_data *pkt_data;
1534 struct ieee80211_hdr *hdr;
1535 u16 fc;
1537 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1539 if (skb->len < 10) {
1540 dev_kfree_skb(skb);
1541 return 0;
1544 if (skb_headroom(skb) < sdata->local->tx_headroom) {
1545 if (pskb_expand_head(skb, sdata->local->tx_headroom,
1546 0, GFP_ATOMIC)) {
1547 dev_kfree_skb(skb);
1548 return 0;
1552 hdr = (struct ieee80211_hdr *) skb->data;
1553 fc = le16_to_cpu(hdr->frame_control);
1555 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
1556 memset(pkt_data, 0, sizeof(struct ieee80211_tx_packet_data));
1557 pkt_data->ifindex = sdata->dev->ifindex;
1558 if (sdata->type == IEEE80211_IF_TYPE_MGMT)
1559 pkt_data->flags |= IEEE80211_TXPD_MGMT_IFACE;
1561 skb->priority = 20; /* use hardcoded priority for mgmt TX queue */
1562 skb->dev = sdata->local->mdev;
1565 * We're using the protocol field of the the frame control header
1566 * to request TX callback for hostapd. BIT(1) is checked.
1568 if ((fc & BIT(1)) == BIT(1)) {
1569 pkt_data->flags |= IEEE80211_TXPD_REQ_TX_STATUS;
1570 fc &= ~BIT(1);
1571 hdr->frame_control = cpu_to_le16(fc);
1574 if (!(fc & IEEE80211_FCTL_PROTECTED))
1575 pkt_data->flags |= IEEE80211_TXPD_DO_NOT_ENCRYPT;
1577 sdata->stats.tx_packets++;
1578 sdata->stats.tx_bytes += skb->len;
1580 dev_queue_xmit(skb);
1582 return 0;
1585 /* helper functions for pending packets for when queues are stopped */
1587 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
1589 int i, j;
1590 struct ieee80211_tx_stored_packet *store;
1592 for (i = 0; i < local->hw.queues; i++) {
1593 if (!__ieee80211_queue_pending(local, i))
1594 continue;
1595 store = &local->pending_packet[i];
1596 kfree_skb(store->skb);
1597 for (j = 0; j < store->num_extra_frag; j++)
1598 kfree_skb(store->extra_frag[j]);
1599 kfree(store->extra_frag);
1600 clear_bit(IEEE80211_LINK_STATE_PENDING, &local->state[i]);
1604 void ieee80211_tx_pending(unsigned long data)
1606 struct ieee80211_local *local = (struct ieee80211_local *)data;
1607 struct net_device *dev = local->mdev;
1608 struct ieee80211_tx_stored_packet *store;
1609 struct ieee80211_txrx_data tx;
1610 int i, ret, reschedule = 0;
1612 netif_tx_lock_bh(dev);
1613 for (i = 0; i < local->hw.queues; i++) {
1614 if (__ieee80211_queue_stopped(local, i))
1615 continue;
1616 if (!__ieee80211_queue_pending(local, i)) {
1617 reschedule = 1;
1618 continue;
1620 store = &local->pending_packet[i];
1621 tx.u.tx.control = &store->control;
1622 tx.u.tx.extra_frag = store->extra_frag;
1623 tx.u.tx.num_extra_frag = store->num_extra_frag;
1624 tx.u.tx.last_frag_hwrate = store->last_frag_hwrate;
1625 tx.u.tx.last_frag_rate = store->last_frag_rate;
1626 tx.flags = 0;
1627 if (store->last_frag_rate_ctrl_probe)
1628 tx.flags |= IEEE80211_TXRXD_TXPROBE_LAST_FRAG;
1629 ret = __ieee80211_tx(local, store->skb, &tx);
1630 if (ret) {
1631 if (ret == IEEE80211_TX_FRAG_AGAIN)
1632 store->skb = NULL;
1633 } else {
1634 clear_bit(IEEE80211_LINK_STATE_PENDING,
1635 &local->state[i]);
1636 reschedule = 1;
1639 netif_tx_unlock_bh(dev);
1640 if (reschedule) {
1641 if (!ieee80211_qdisc_installed(dev)) {
1642 if (!__ieee80211_queue_stopped(local, 0))
1643 netif_wake_queue(dev);
1644 } else
1645 netif_schedule(dev);
1649 /* functions for drivers to get certain frames */
1651 static void ieee80211_beacon_add_tim(struct ieee80211_local *local,
1652 struct ieee80211_if_ap *bss,
1653 struct sk_buff *skb)
1655 u8 *pos, *tim;
1656 int aid0 = 0;
1657 int i, have_bits = 0, n1, n2;
1659 /* Generate bitmap for TIM only if there are any STAs in power save
1660 * mode. */
1661 read_lock_bh(&local->sta_lock);
1662 if (atomic_read(&bss->num_sta_ps) > 0)
1663 /* in the hope that this is faster than
1664 * checking byte-for-byte */
1665 have_bits = !bitmap_empty((unsigned long*)bss->tim,
1666 IEEE80211_MAX_AID+1);
1668 if (bss->dtim_count == 0)
1669 bss->dtim_count = bss->dtim_period - 1;
1670 else
1671 bss->dtim_count--;
1673 tim = pos = (u8 *) skb_put(skb, 6);
1674 *pos++ = WLAN_EID_TIM;
1675 *pos++ = 4;
1676 *pos++ = bss->dtim_count;
1677 *pos++ = bss->dtim_period;
1679 if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
1680 aid0 = 1;
1682 if (have_bits) {
1683 /* Find largest even number N1 so that bits numbered 1 through
1684 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
1685 * (N2 + 1) x 8 through 2007 are 0. */
1686 n1 = 0;
1687 for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
1688 if (bss->tim[i]) {
1689 n1 = i & 0xfe;
1690 break;
1693 n2 = n1;
1694 for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
1695 if (bss->tim[i]) {
1696 n2 = i;
1697 break;
1701 /* Bitmap control */
1702 *pos++ = n1 | aid0;
1703 /* Part Virt Bitmap */
1704 memcpy(pos, bss->tim + n1, n2 - n1 + 1);
1706 tim[1] = n2 - n1 + 4;
1707 skb_put(skb, n2 - n1);
1708 } else {
1709 *pos++ = aid0; /* Bitmap control */
1710 *pos++ = 0; /* Part Virt Bitmap */
1712 read_unlock_bh(&local->sta_lock);
1715 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id,
1716 struct ieee80211_tx_control *control)
1718 struct ieee80211_local *local = hw_to_local(hw);
1719 struct sk_buff *skb;
1720 struct net_device *bdev;
1721 struct ieee80211_sub_if_data *sdata = NULL;
1722 struct ieee80211_if_ap *ap = NULL;
1723 struct ieee80211_rate *rate;
1724 struct rate_control_extra extra;
1725 u8 *b_head, *b_tail;
1726 int bh_len, bt_len;
1728 bdev = dev_get_by_index(if_id);
1729 if (bdev) {
1730 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
1731 ap = &sdata->u.ap;
1732 dev_put(bdev);
1735 if (!ap || sdata->type != IEEE80211_IF_TYPE_AP ||
1736 !ap->beacon_head) {
1737 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1738 if (net_ratelimit())
1739 printk(KERN_DEBUG "no beacon data avail for idx=%d "
1740 "(%s)\n", if_id, bdev ? bdev->name : "N/A");
1741 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
1742 return NULL;
1745 /* Assume we are generating the normal beacon locally */
1746 b_head = ap->beacon_head;
1747 b_tail = ap->beacon_tail;
1748 bh_len = ap->beacon_head_len;
1749 bt_len = ap->beacon_tail_len;
1751 skb = dev_alloc_skb(local->tx_headroom +
1752 bh_len + bt_len + 256 /* maximum TIM len */);
1753 if (!skb)
1754 return NULL;
1756 skb_reserve(skb, local->tx_headroom);
1757 memcpy(skb_put(skb, bh_len), b_head, bh_len);
1759 ieee80211_include_sequence(sdata, (struct ieee80211_hdr *)skb->data);
1761 ieee80211_beacon_add_tim(local, ap, skb);
1763 if (b_tail) {
1764 memcpy(skb_put(skb, bt_len), b_tail, bt_len);
1767 if (control) {
1768 memset(&extra, 0, sizeof(extra));
1769 extra.mode = local->oper_hw_mode;
1771 rate = rate_control_get_rate(local, local->mdev, skb, &extra);
1772 if (!rate) {
1773 if (net_ratelimit()) {
1774 printk(KERN_DEBUG "%s: ieee80211_beacon_get: no rate "
1775 "found\n", local->mdev->name);
1777 dev_kfree_skb(skb);
1778 return NULL;
1781 control->tx_rate =
1782 ((sdata->flags & IEEE80211_SDATA_SHORT_PREAMBLE) &&
1783 (rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
1784 rate->val2 : rate->val;
1785 control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
1786 control->power_level = local->hw.conf.power_level;
1787 control->flags |= IEEE80211_TXCTL_NO_ACK;
1788 control->retry_limit = 1;
1789 control->flags |= IEEE80211_TXCTL_CLEAR_DST_MASK;
1792 ap->num_beacons++;
1793 return skb;
1795 EXPORT_SYMBOL(ieee80211_beacon_get);
1797 void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
1798 const void *frame, size_t frame_len,
1799 const struct ieee80211_tx_control *frame_txctl,
1800 struct ieee80211_rts *rts)
1802 const struct ieee80211_hdr *hdr = frame;
1803 u16 fctl;
1805 fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS;
1806 rts->frame_control = cpu_to_le16(fctl);
1807 rts->duration = ieee80211_rts_duration(hw, if_id, frame_len, frame_txctl);
1808 memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
1809 memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
1811 EXPORT_SYMBOL(ieee80211_rts_get);
1813 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
1814 const void *frame, size_t frame_len,
1815 const struct ieee80211_tx_control *frame_txctl,
1816 struct ieee80211_cts *cts)
1818 const struct ieee80211_hdr *hdr = frame;
1819 u16 fctl;
1821 fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
1822 cts->frame_control = cpu_to_le16(fctl);
1823 cts->duration = ieee80211_ctstoself_duration(hw, if_id, frame_len, frame_txctl);
1824 memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
1826 EXPORT_SYMBOL(ieee80211_ctstoself_get);
1828 struct sk_buff *
1829 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, int if_id,
1830 struct ieee80211_tx_control *control)
1832 struct ieee80211_local *local = hw_to_local(hw);
1833 struct sk_buff *skb;
1834 struct sta_info *sta;
1835 ieee80211_tx_handler *handler;
1836 struct ieee80211_txrx_data tx;
1837 ieee80211_txrx_result res = TXRX_DROP;
1838 struct net_device *bdev;
1839 struct ieee80211_sub_if_data *sdata;
1840 struct ieee80211_if_ap *bss = NULL;
1842 bdev = dev_get_by_index(if_id);
1843 if (bdev) {
1844 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
1845 bss = &sdata->u.ap;
1846 dev_put(bdev);
1848 if (!bss || sdata->type != IEEE80211_IF_TYPE_AP || !bss->beacon_head)
1849 return NULL;
1851 if (bss->dtim_count != 0)
1852 return NULL; /* send buffered bc/mc only after DTIM beacon */
1853 memset(control, 0, sizeof(*control));
1854 while (1) {
1855 skb = skb_dequeue(&bss->ps_bc_buf);
1856 if (!skb)
1857 return NULL;
1858 local->total_ps_buffered--;
1860 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
1861 struct ieee80211_hdr *hdr =
1862 (struct ieee80211_hdr *) skb->data;
1863 /* more buffered multicast/broadcast frames ==> set
1864 * MoreData flag in IEEE 802.11 header to inform PS
1865 * STAs */
1866 hdr->frame_control |=
1867 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1870 if (ieee80211_tx_prepare(&tx, skb, local->mdev, control) == 0)
1871 break;
1872 dev_kfree_skb_any(skb);
1874 sta = tx.sta;
1875 tx.flags |= IEEE80211_TXRXD_TXPS_BUFFERED;
1877 for (handler = local->tx_handlers; *handler != NULL; handler++) {
1878 res = (*handler)(&tx);
1879 if (res == TXRX_DROP || res == TXRX_QUEUED)
1880 break;
1882 dev_put(tx.dev);
1883 skb = tx.skb; /* handlers are allowed to change skb */
1885 if (res == TXRX_DROP) {
1886 I802_DEBUG_INC(local->tx_handlers_drop);
1887 dev_kfree_skb(skb);
1888 skb = NULL;
1889 } else if (res == TXRX_QUEUED) {
1890 I802_DEBUG_INC(local->tx_handlers_queued);
1891 skb = NULL;
1894 if (sta)
1895 sta_info_put(sta);
1897 return skb;
1899 EXPORT_SYMBOL(ieee80211_get_buffered_bc);