1 /* Copyright (c) 2014 Broadcom Corporation
2  *
3  * Permission to use, copy, modify, and/or distribute this software for any
4  * purpose with or without fee is hereby granted, provided that the above
5  * copyright notice and this permission notice appear in all copies.
6  *
7  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14  */
15 
16 
17 #include <linux/types.h>
18 #include <linux/netdevice.h>
19 #include <linux/etherdevice.h>
20 #include <brcmu_utils.h>
21 
22 #include "core.h"
23 #include "debug.h"
24 #include "bus.h"
25 #include "proto.h"
26 #include "flowring.h"
27 #include "msgbuf.h"
28 #include "common.h"
29 
30 
31 #define BRCMF_FLOWRING_HIGH		1024
32 #define BRCMF_FLOWRING_LOW		(BRCMF_FLOWRING_HIGH - 256)
33 #define BRCMF_FLOWRING_INVALID_IFIDX	0xff
34 
35 #define BRCMF_FLOWRING_HASH_AP(da, fifo, ifidx) (da[5] * 2 + fifo + ifidx * 16)
36 #define BRCMF_FLOWRING_HASH_STA(fifo, ifidx) (fifo + ifidx * 16)
37 
38 static const u8 brcmf_flowring_prio2fifo[] = {
39 	1,
40 	0,
41 	0,
42 	1,
43 	2,
44 	2,
45 	3,
46 	3
47 };
48 
49 
50 static bool
51 brcmf_flowring_is_tdls_mac(struct brcmf_flowring *flow, u8 mac[ETH_ALEN])
52 {
53 	struct brcmf_flowring_tdls_entry *search;
54 
55 	search = flow->tdls_entry;
56 
57 	while (search) {
58 		if (memcmp(search->mac, mac, ETH_ALEN) == 0)
59 			return true;
60 		search = search->next;
61 	}
62 
63 	return false;
64 }
65 
66 
67 u32 brcmf_flowring_lookup(struct brcmf_flowring *flow, u8 da[ETH_ALEN],
68 			  u8 prio, u8 ifidx)
69 {
70 	struct brcmf_flowring_hash *hash;
71 	u16 hash_idx;
72 	u32 i;
73 	bool found;
74 	bool sta;
75 	u8 fifo;
76 	u8 *mac;
77 
78 	fifo = brcmf_flowring_prio2fifo[prio];
79 	sta = (flow->addr_mode[ifidx] == ADDR_INDIRECT);
80 	mac = da;
81 	if ((!sta) && (is_multicast_ether_addr(da))) {
82 		mac = (u8 *)ALLFFMAC;
83 		fifo = 0;
84 	}
85 	if ((sta) && (flow->tdls_active) &&
86 	    (brcmf_flowring_is_tdls_mac(flow, da))) {
87 		sta = false;
88 	}
89 	hash_idx =  sta ? BRCMF_FLOWRING_HASH_STA(fifo, ifidx) :
90 			  BRCMF_FLOWRING_HASH_AP(mac, fifo, ifidx);
91 	hash_idx &= (BRCMF_FLOWRING_HASHSIZE - 1);
92 	found = false;
93 	hash = flow->hash;
94 	for (i = 0; i < BRCMF_FLOWRING_HASHSIZE; i++) {
95 		if ((sta || (memcmp(hash[hash_idx].mac, mac, ETH_ALEN) == 0)) &&
96 		    (hash[hash_idx].fifo == fifo) &&
97 		    (hash[hash_idx].ifidx == ifidx)) {
98 			found = true;
99 			break;
100 		}
101 		hash_idx++;
102 		hash_idx &= (BRCMF_FLOWRING_HASHSIZE - 1);
103 	}
104 	if (found)
105 		return hash[hash_idx].flowid;
106 
107 	return BRCMF_FLOWRING_INVALID_ID;
108 }
109 
110 
111 u32 brcmf_flowring_create(struct brcmf_flowring *flow, u8 da[ETH_ALEN],
112 			  u8 prio, u8 ifidx)
113 {
114 	struct brcmf_flowring_ring *ring;
115 	struct brcmf_flowring_hash *hash;
116 	u16 hash_idx;
117 	u32 i;
118 	bool found;
119 	u8 fifo;
120 	bool sta;
121 	u8 *mac;
122 
123 	fifo = brcmf_flowring_prio2fifo[prio];
124 	sta = (flow->addr_mode[ifidx] == ADDR_INDIRECT);
125 	mac = da;
126 	if ((!sta) && (is_multicast_ether_addr(da))) {
127 		mac = (u8 *)ALLFFMAC;
128 		fifo = 0;
129 	}
130 	if ((sta) && (flow->tdls_active) &&
131 	    (brcmf_flowring_is_tdls_mac(flow, da))) {
132 		sta = false;
133 	}
134 	hash_idx =  sta ? BRCMF_FLOWRING_HASH_STA(fifo, ifidx) :
135 			  BRCMF_FLOWRING_HASH_AP(mac, fifo, ifidx);
136 	hash_idx &= (BRCMF_FLOWRING_HASHSIZE - 1);
137 	found = false;
138 	hash = flow->hash;
139 	for (i = 0; i < BRCMF_FLOWRING_HASHSIZE; i++) {
140 		if ((hash[hash_idx].ifidx == BRCMF_FLOWRING_INVALID_IFIDX) &&
141 		    (is_zero_ether_addr(hash[hash_idx].mac))) {
142 			found = true;
143 			break;
144 		}
145 		hash_idx++;
146 		hash_idx &= (BRCMF_FLOWRING_HASHSIZE - 1);
147 	}
148 	if (found) {
149 		for (i = 0; i < flow->nrofrings; i++) {
150 			if (flow->rings[i] == NULL)
151 				break;
152 		}
153 		if (i == flow->nrofrings)
154 			return -ENOMEM;
155 
156 		ring = kzalloc(sizeof(*ring), GFP_ATOMIC);
157 		if (!ring)
158 			return -ENOMEM;
159 
160 		memcpy(hash[hash_idx].mac, mac, ETH_ALEN);
161 		hash[hash_idx].fifo = fifo;
162 		hash[hash_idx].ifidx = ifidx;
163 		hash[hash_idx].flowid = i;
164 
165 		ring->hash_id = hash_idx;
166 		ring->status = RING_CLOSED;
167 		skb_queue_head_init(&ring->skblist);
168 		flow->rings[i] = ring;
169 
170 		return i;
171 	}
172 	return BRCMF_FLOWRING_INVALID_ID;
173 }
174 
175 
176 u8 brcmf_flowring_tid(struct brcmf_flowring *flow, u16 flowid)
177 {
178 	struct brcmf_flowring_ring *ring;
179 
180 	ring = flow->rings[flowid];
181 
182 	return flow->hash[ring->hash_id].fifo;
183 }
184 
185 
186 static void brcmf_flowring_block(struct brcmf_flowring *flow, u16 flowid,
187 				 bool blocked)
188 {
189 	struct brcmf_flowring_ring *ring;
190 	struct brcmf_bus *bus_if;
191 	struct brcmf_pub *drvr;
192 	struct brcmf_if *ifp;
193 	bool currently_blocked;
194 	int i;
195 	u8 ifidx;
196 	unsigned long flags;
197 
198 	spin_lock_irqsave(&flow->block_lock, flags);
199 
200 	ring = flow->rings[flowid];
201 	if (ring->blocked == blocked) {
202 		spin_unlock_irqrestore(&flow->block_lock, flags);
203 		return;
204 	}
205 	ifidx = brcmf_flowring_ifidx_get(flow, flowid);
206 
207 	currently_blocked = false;
208 	for (i = 0; i < flow->nrofrings; i++) {
209 		if ((flow->rings[i]) && (i != flowid)) {
210 			ring = flow->rings[i];
211 			if ((ring->status == RING_OPEN) &&
212 			    (brcmf_flowring_ifidx_get(flow, i) == ifidx)) {
213 				if (ring->blocked) {
214 					currently_blocked = true;
215 					break;
216 				}
217 			}
218 		}
219 	}
220 	flow->rings[flowid]->blocked = blocked;
221 	if (currently_blocked) {
222 		spin_unlock_irqrestore(&flow->block_lock, flags);
223 		return;
224 	}
225 
226 	bus_if = dev_get_drvdata(flow->dev);
227 	drvr = bus_if->drvr;
228 	ifp = brcmf_get_ifp(drvr, ifidx);
229 	brcmf_txflowblock_if(ifp, BRCMF_NETIF_STOP_REASON_FLOW, blocked);
230 
231 	spin_unlock_irqrestore(&flow->block_lock, flags);
232 }
233 
234 
235 void brcmf_flowring_delete(struct brcmf_flowring *flow, u16 flowid)
236 {
237 	struct brcmf_flowring_ring *ring;
238 	u16 hash_idx;
239 	struct sk_buff *skb;
240 
241 	ring = flow->rings[flowid];
242 	if (!ring)
243 		return;
244 	brcmf_flowring_block(flow, flowid, false);
245 	hash_idx = ring->hash_id;
246 	flow->hash[hash_idx].ifidx = BRCMF_FLOWRING_INVALID_IFIDX;
247 	eth_zero_addr(flow->hash[hash_idx].mac);
248 	flow->rings[flowid] = NULL;
249 
250 	skb = skb_dequeue(&ring->skblist);
251 	while (skb) {
252 		brcmu_pkt_buf_free_skb(skb);
253 		skb = skb_dequeue(&ring->skblist);
254 	}
255 
256 	kfree(ring);
257 }
258 
259 
260 u32 brcmf_flowring_enqueue(struct brcmf_flowring *flow, u16 flowid,
261 			   struct sk_buff *skb)
262 {
263 	struct brcmf_flowring_ring *ring;
264 
265 	ring = flow->rings[flowid];
266 
267 	skb_queue_tail(&ring->skblist, skb);
268 
269 	if (!ring->blocked &&
270 	    (skb_queue_len(&ring->skblist) > BRCMF_FLOWRING_HIGH)) {
271 		brcmf_flowring_block(flow, flowid, true);
272 		brcmf_dbg(MSGBUF, "Flowcontrol: BLOCK for ring %d\n", flowid);
273 		/* To prevent (work around) possible race condition, check
274 		 * queue len again. It is also possible to use locking to
275 		 * protect, but that is undesirable for every enqueue and
276 		 * dequeue. This simple check will solve a possible race
277 		 * condition if it occurs.
278 		 */
279 		if (skb_queue_len(&ring->skblist) < BRCMF_FLOWRING_LOW)
280 			brcmf_flowring_block(flow, flowid, false);
281 	}
282 	return skb_queue_len(&ring->skblist);
283 }
284 
285 
286 struct sk_buff *brcmf_flowring_dequeue(struct brcmf_flowring *flow, u16 flowid)
287 {
288 	struct brcmf_flowring_ring *ring;
289 	struct sk_buff *skb;
290 
291 	ring = flow->rings[flowid];
292 	if (ring->status != RING_OPEN)
293 		return NULL;
294 
295 	skb = skb_dequeue(&ring->skblist);
296 
297 	if (ring->blocked &&
298 	    (skb_queue_len(&ring->skblist) < BRCMF_FLOWRING_LOW)) {
299 		brcmf_flowring_block(flow, flowid, false);
300 		brcmf_dbg(MSGBUF, "Flowcontrol: OPEN for ring %d\n", flowid);
301 	}
302 
303 	return skb;
304 }
305 
306 
307 void brcmf_flowring_reinsert(struct brcmf_flowring *flow, u16 flowid,
308 			     struct sk_buff *skb)
309 {
310 	struct brcmf_flowring_ring *ring;
311 
312 	ring = flow->rings[flowid];
313 
314 	skb_queue_head(&ring->skblist, skb);
315 }
316 
317 
318 u32 brcmf_flowring_qlen(struct brcmf_flowring *flow, u16 flowid)
319 {
320 	struct brcmf_flowring_ring *ring;
321 
322 	ring = flow->rings[flowid];
323 	if (!ring)
324 		return 0;
325 
326 	if (ring->status != RING_OPEN)
327 		return 0;
328 
329 	return skb_queue_len(&ring->skblist);
330 }
331 
332 
333 void brcmf_flowring_open(struct brcmf_flowring *flow, u16 flowid)
334 {
335 	struct brcmf_flowring_ring *ring;
336 
337 	ring = flow->rings[flowid];
338 	if (!ring) {
339 		brcmf_err("Ring NULL, for flowid %d\n", flowid);
340 		return;
341 	}
342 
343 	ring->status = RING_OPEN;
344 }
345 
346 
347 u8 brcmf_flowring_ifidx_get(struct brcmf_flowring *flow, u16 flowid)
348 {
349 	struct brcmf_flowring_ring *ring;
350 	u16 hash_idx;
351 
352 	ring = flow->rings[flowid];
353 	hash_idx = ring->hash_id;
354 
355 	return flow->hash[hash_idx].ifidx;
356 }
357 
358 
359 struct brcmf_flowring *brcmf_flowring_attach(struct device *dev, u16 nrofrings)
360 {
361 	struct brcmf_flowring *flow;
362 	u32 i;
363 
364 	flow = kzalloc(sizeof(*flow), GFP_KERNEL);
365 	if (flow) {
366 		flow->dev = dev;
367 		flow->nrofrings = nrofrings;
368 		spin_lock_init(&flow->block_lock);
369 		for (i = 0; i < ARRAY_SIZE(flow->addr_mode); i++)
370 			flow->addr_mode[i] = ADDR_INDIRECT;
371 		for (i = 0; i < ARRAY_SIZE(flow->hash); i++)
372 			flow->hash[i].ifidx = BRCMF_FLOWRING_INVALID_IFIDX;
373 		flow->rings = kcalloc(nrofrings, sizeof(*flow->rings),
374 				      GFP_KERNEL);
375 		if (!flow->rings) {
376 			kfree(flow);
377 			flow = NULL;
378 		}
379 	}
380 
381 	return flow;
382 }
383 
384 
385 void brcmf_flowring_detach(struct brcmf_flowring *flow)
386 {
387 	struct brcmf_bus *bus_if = dev_get_drvdata(flow->dev);
388 	struct brcmf_pub *drvr = bus_if->drvr;
389 	struct brcmf_flowring_tdls_entry *search;
390 	struct brcmf_flowring_tdls_entry *remove;
391 	u16 flowid;
392 
393 	for (flowid = 0; flowid < flow->nrofrings; flowid++) {
394 		if (flow->rings[flowid])
395 			brcmf_msgbuf_delete_flowring(drvr, flowid);
396 	}
397 
398 	search = flow->tdls_entry;
399 	while (search) {
400 		remove = search;
401 		search = search->next;
402 		kfree(remove);
403 	}
404 	kfree(flow->rings);
405 	kfree(flow);
406 }
407 
408 
409 void brcmf_flowring_configure_addr_mode(struct brcmf_flowring *flow, int ifidx,
410 					enum proto_addr_mode addr_mode)
411 {
412 	struct brcmf_bus *bus_if = dev_get_drvdata(flow->dev);
413 	struct brcmf_pub *drvr = bus_if->drvr;
414 	u32 i;
415 	u16 flowid;
416 
417 	if (flow->addr_mode[ifidx] != addr_mode) {
418 		for (i = 0; i < ARRAY_SIZE(flow->hash); i++) {
419 			if (flow->hash[i].ifidx == ifidx) {
420 				flowid = flow->hash[i].flowid;
421 				if (flow->rings[flowid]->status != RING_OPEN)
422 					continue;
423 				flow->rings[flowid]->status = RING_CLOSING;
424 				brcmf_msgbuf_delete_flowring(drvr, flowid);
425 			}
426 		}
427 		flow->addr_mode[ifidx] = addr_mode;
428 	}
429 }
430 
431 
432 void brcmf_flowring_delete_peer(struct brcmf_flowring *flow, int ifidx,
433 				u8 peer[ETH_ALEN])
434 {
435 	struct brcmf_bus *bus_if = dev_get_drvdata(flow->dev);
436 	struct brcmf_pub *drvr = bus_if->drvr;
437 	struct brcmf_flowring_hash *hash;
438 	struct brcmf_flowring_tdls_entry *prev;
439 	struct brcmf_flowring_tdls_entry *search;
440 	u32 i;
441 	u16 flowid;
442 	bool sta;
443 
444 	sta = (flow->addr_mode[ifidx] == ADDR_INDIRECT);
445 
446 	search = flow->tdls_entry;
447 	prev = NULL;
448 	while (search) {
449 		if (memcmp(search->mac, peer, ETH_ALEN) == 0) {
450 			sta = false;
451 			break;
452 		}
453 		prev = search;
454 		search = search->next;
455 	}
456 
457 	hash = flow->hash;
458 	for (i = 0; i < BRCMF_FLOWRING_HASHSIZE; i++) {
459 		if ((sta || (memcmp(hash[i].mac, peer, ETH_ALEN) == 0)) &&
460 		    (hash[i].ifidx == ifidx)) {
461 			flowid = flow->hash[i].flowid;
462 			if (flow->rings[flowid]->status == RING_OPEN) {
463 				flow->rings[flowid]->status = RING_CLOSING;
464 				brcmf_msgbuf_delete_flowring(drvr, flowid);
465 			}
466 		}
467 	}
468 
469 	if (search) {
470 		if (prev)
471 			prev->next = search->next;
472 		else
473 			flow->tdls_entry = search->next;
474 		kfree(search);
475 		if (flow->tdls_entry == NULL)
476 			flow->tdls_active = false;
477 	}
478 }
479 
480 
481 void brcmf_flowring_add_tdls_peer(struct brcmf_flowring *flow, int ifidx,
482 				  u8 peer[ETH_ALEN])
483 {
484 	struct brcmf_flowring_tdls_entry *tdls_entry;
485 	struct brcmf_flowring_tdls_entry *search;
486 
487 	tdls_entry = kzalloc(sizeof(*tdls_entry), GFP_ATOMIC);
488 	if (tdls_entry == NULL)
489 		return;
490 
491 	memcpy(tdls_entry->mac, peer, ETH_ALEN);
492 	tdls_entry->next = NULL;
493 	if (flow->tdls_entry == NULL) {
494 		flow->tdls_entry = tdls_entry;
495 	} else {
496 		search = flow->tdls_entry;
497 		if (memcmp(search->mac, peer, ETH_ALEN) == 0)
498 			return;
499 		while (search->next) {
500 			search = search->next;
501 			if (memcmp(search->mac, peer, ETH_ALEN) == 0)
502 				return;
503 		}
504 		search->next = tdls_entry;
505 	}
506 
507 	flow->tdls_active = true;
508 }
509