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Diffstat (limited to 'drivers/uwb/wlp/eda.c')
-rw-r--r--drivers/uwb/wlp/eda.c449
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/uwb/wlp/eda.c b/drivers/uwb/wlp/eda.c
new file mode 100644
index 000000000000..cdfe8dfc4340
--- /dev/null
+++ b/drivers/uwb/wlp/eda.c
@@ -0,0 +1,449 @@
1/*
2 * WUSB Wire Adapter: WLP interface
3 * Ethernet to device address cache
4 *
5 * Copyright (C) 2005-2006 Intel Corporation
6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 * 02110-1301, USA.
21 *
22 *
23 * We need to be able to map ethernet addresses to device addresses
24 * and back because there is not explicit relationship between the eth
25 * addresses used in the ETH frames and the device addresses (no, it
26 * would not have been simpler to force as ETH address the MBOA MAC
27 * address...no, not at all :).
28 *
29 * A device has one MBOA MAC address and one device address. It is possible
30 * for a device to have more than one virtual MAC address (although a
31 * virtual address can be the same as the MBOA MAC address). The device
32 * address is guaranteed to be unique among the devices in the extended
33 * beacon group (see ECMA 17.1.1). We thus use the device address as index
34 * to this cache. We do allow searching based on virtual address as this
35 * is how Ethernet frames will be addressed.
36 *
37 * We need to support virtual EUI-48. Although, right now the virtual
38 * EUI-48 will always be the same as the MAC SAP address. The EDA cache
39 * entry thus contains a MAC SAP address as well as the virtual address
40 * (used to map the network stack address to a neighbor). When we move
41 * to support more than one virtual MAC on a host then this organization
42 * will have to change. Perhaps a neighbor has a list of WSSs, each with a
43 * tag and virtual EUI-48.
44 *
45 * On data transmission
46 * it is used to determine if the neighbor is connected and what WSS it
47 * belongs to. With this we know what tag to add to the WLP frame. Storing
48 * the WSS in the EDA cache may be overkill because we only support one
49 * WSS. Hopefully we will support more than one WSS at some point.
50 * On data reception it is used to determine the WSS based on
51 * the tag and address of the transmitting neighbor.
52 */
53
54#define D_LOCAL 5
55#include <linux/netdevice.h>
56#include <linux/uwb/debug.h>
57#include <linux/etherdevice.h>
58#include <linux/wlp.h>
59#include "wlp-internal.h"
60
61
62/* FIXME: cache is not purged, only on device close */
63
64/* FIXME: does not scale, change to dynamic array */
65
66/*
67 * Initialize the EDA cache
68 *
69 * @returns 0 if ok, < 0 errno code on error
70 *
71 * Call when the interface is being brought up
72 *
73 * NOTE: Keep it as a separate function as the implementation will
74 * change and be more complex.
75 */
76void wlp_eda_init(struct wlp_eda *eda)
77{
78 INIT_LIST_HEAD(&eda->cache);
79 spin_lock_init(&eda->lock);
80}
81
82/*
83 * Release the EDA cache
84 *
85 * @returns 0 if ok, < 0 errno code on error
86 *
87 * Called when the interface is brought down
88 */
89void wlp_eda_release(struct wlp_eda *eda)
90{
91 unsigned long flags;
92 struct wlp_eda_node *itr, *next;
93
94 spin_lock_irqsave(&eda->lock, flags);
95 list_for_each_entry_safe(itr, next, &eda->cache, list_node) {
96 list_del(&itr->list_node);
97 kfree(itr);
98 }
99 spin_unlock_irqrestore(&eda->lock, flags);
100}
101
102/*
103 * Add an address mapping
104 *
105 * @returns 0 if ok, < 0 errno code on error
106 *
107 * An address mapping is initially created when the neighbor device is seen
108 * for the first time (it is "onair"). At this time the neighbor is not
109 * connected or associated with a WSS so we only populate the Ethernet and
110 * Device address fields.
111 *
112 */
113int wlp_eda_create_node(struct wlp_eda *eda,
114 const unsigned char eth_addr[ETH_ALEN],
115 const struct uwb_dev_addr *dev_addr)
116{
117 int result = 0;
118 struct wlp_eda_node *itr;
119 unsigned long flags;
120
121 BUG_ON(dev_addr == NULL || eth_addr == NULL);
122 spin_lock_irqsave(&eda->lock, flags);
123 list_for_each_entry(itr, &eda->cache, list_node) {
124 if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
125 printk(KERN_ERR "EDA cache already contains entry "
126 "for neighbor %02x:%02x\n",
127 dev_addr->data[1], dev_addr->data[0]);
128 result = -EEXIST;
129 goto out_unlock;
130 }
131 }
132 itr = kzalloc(sizeof(*itr), GFP_ATOMIC);
133 if (itr != NULL) {
134 memcpy(itr->eth_addr, eth_addr, sizeof(itr->eth_addr));
135 itr->dev_addr = *dev_addr;
136 list_add(&itr->list_node, &eda->cache);
137 } else
138 result = -ENOMEM;
139out_unlock:
140 spin_unlock_irqrestore(&eda->lock, flags);
141 return result;
142}
143
144/*
145 * Remove entry from EDA cache
146 *
147 * This is done when the device goes off air.
148 */
149void wlp_eda_rm_node(struct wlp_eda *eda, const struct uwb_dev_addr *dev_addr)
150{
151 struct wlp_eda_node *itr, *next;
152 unsigned long flags;
153
154 spin_lock_irqsave(&eda->lock, flags);
155 list_for_each_entry_safe(itr, next, &eda->cache, list_node) {
156 if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
157 list_del(&itr->list_node);
158 kfree(itr);
159 break;
160 }
161 }
162 spin_unlock_irqrestore(&eda->lock, flags);
163}
164
165/*
166 * Update an address mapping
167 *
168 * @returns 0 if ok, < 0 errno code on error
169 */
170int wlp_eda_update_node(struct wlp_eda *eda,
171 const struct uwb_dev_addr *dev_addr,
172 struct wlp_wss *wss,
173 const unsigned char virt_addr[ETH_ALEN],
174 const u8 tag, const enum wlp_wss_connect state)
175{
176 int result = -ENOENT;
177 struct wlp_eda_node *itr;
178 unsigned long flags;
179
180 spin_lock_irqsave(&eda->lock, flags);
181 list_for_each_entry(itr, &eda->cache, list_node) {
182 if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
183 /* Found it, update it */
184 itr->wss = wss;
185 memcpy(itr->virt_addr, virt_addr,
186 sizeof(itr->virt_addr));
187 itr->tag = tag;
188 itr->state = state;
189 result = 0;
190 goto out_unlock;
191 }
192 }
193 /* Not found */
194out_unlock:
195 spin_unlock_irqrestore(&eda->lock, flags);
196 return result;
197}
198
199/*
200 * Update only state field of an address mapping
201 *
202 * @returns 0 if ok, < 0 errno code on error
203 */
204int wlp_eda_update_node_state(struct wlp_eda *eda,
205 const struct uwb_dev_addr *dev_addr,
206 const enum wlp_wss_connect state)
207{
208 int result = -ENOENT;
209 struct wlp_eda_node *itr;
210 unsigned long flags;
211
212 spin_lock_irqsave(&eda->lock, flags);
213 list_for_each_entry(itr, &eda->cache, list_node) {
214 if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
215 /* Found it, update it */
216 itr->state = state;
217 result = 0;
218 goto out_unlock;
219 }
220 }
221 /* Not found */
222out_unlock:
223 spin_unlock_irqrestore(&eda->lock, flags);
224 return result;
225}
226
227/*
228 * Return contents of EDA cache entry
229 *
230 * @dev_addr: index to EDA cache
231 * @eda_entry: pointer to where contents of EDA cache will be copied
232 */
233int wlp_copy_eda_node(struct wlp_eda *eda, struct uwb_dev_addr *dev_addr,
234 struct wlp_eda_node *eda_entry)
235{
236 int result = -ENOENT;
237 struct wlp_eda_node *itr;
238 unsigned long flags;
239
240 spin_lock_irqsave(&eda->lock, flags);
241 list_for_each_entry(itr, &eda->cache, list_node) {
242 if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
243 *eda_entry = *itr;
244 result = 0;
245 goto out_unlock;
246 }
247 }
248 /* Not found */
249out_unlock:
250 spin_unlock_irqrestore(&eda->lock, flags);
251 return result;
252}
253
254/*
255 * Execute function for every element in the cache
256 *
257 * @function: function to execute on element of cache (must be atomic)
258 * @priv: private data of function
259 * @returns: result of first function that failed, or last function
260 * executed if no function failed.
261 *
262 * Stop executing when function returns error for any element in cache.
263 *
264 * IMPORTANT: We are using a spinlock here: the function executed on each
265 * element has to be atomic.
266 */
267int wlp_eda_for_each(struct wlp_eda *eda, wlp_eda_for_each_f function,
268 void *priv)
269{
270 int result = 0;
271 struct wlp *wlp = container_of(eda, struct wlp, eda);
272 struct wlp_eda_node *entry;
273 unsigned long flags;
274
275 spin_lock_irqsave(&eda->lock, flags);
276 list_for_each_entry(entry, &eda->cache, list_node) {
277 result = (*function)(wlp, entry, priv);
278 if (result < 0)
279 break;
280 }
281 spin_unlock_irqrestore(&eda->lock, flags);
282 return result;
283}
284
285/*
286 * Execute function for single element in the cache (return dev addr)
287 *
288 * @virt_addr: index into EDA cache used to determine which element to
289 * execute the function on
290 * @dev_addr: device address of element in cache will be returned using
291 * @dev_addr
292 * @function: function to execute on element of cache (must be atomic)
293 * @priv: private data of function
294 * @returns: result of function
295 *
296 * IMPORTANT: We are using a spinlock here: the function executed on the
297 * element has to be atomic.
298 */
299int wlp_eda_for_virtual(struct wlp_eda *eda,
300 const unsigned char virt_addr[ETH_ALEN],
301 struct uwb_dev_addr *dev_addr,
302 wlp_eda_for_each_f function,
303 void *priv)
304{
305 int result = 0;
306 struct wlp *wlp = container_of(eda, struct wlp, eda);
307 struct device *dev = &wlp->rc->uwb_dev.dev;
308 struct wlp_eda_node *itr;
309 unsigned long flags;
310 int found = 0;
311
312 spin_lock_irqsave(&eda->lock, flags);
313 list_for_each_entry(itr, &eda->cache, list_node) {
314 if (!memcmp(itr->virt_addr, virt_addr,
315 sizeof(itr->virt_addr))) {
316 d_printf(6, dev, "EDA: looking for "
317 "%02x:%02x:%02x:%02x:%02x:%02x hit %02x:%02x "
318 "wss %p tag 0x%02x state %u\n",
319 virt_addr[0], virt_addr[1],
320 virt_addr[2], virt_addr[3],
321 virt_addr[4], virt_addr[5],
322 itr->dev_addr.data[1],
323 itr->dev_addr.data[0], itr->wss,
324 itr->tag, itr->state);
325 result = (*function)(wlp, itr, priv);
326 *dev_addr = itr->dev_addr;
327 found = 1;
328 break;
329 } else
330 d_printf(6, dev, "EDA: looking for "
331 "%02x:%02x:%02x:%02x:%02x:%02x "
332 "against "
333 "%02x:%02x:%02x:%02x:%02x:%02x miss\n",
334 virt_addr[0], virt_addr[1],
335 virt_addr[2], virt_addr[3],
336 virt_addr[4], virt_addr[5],
337 itr->virt_addr[0], itr->virt_addr[1],
338 itr->virt_addr[2], itr->virt_addr[3],
339 itr->virt_addr[4], itr->virt_addr[5]);
340 }
341 if (!found) {
342 if (printk_ratelimit())
343 dev_err(dev, "EDA: Eth addr %02x:%02x:%02x"
344 ":%02x:%02x:%02x not found.\n",
345 virt_addr[0], virt_addr[1],
346 virt_addr[2], virt_addr[3],
347 virt_addr[4], virt_addr[5]);
348 result = -ENODEV;
349 }
350 spin_unlock_irqrestore(&eda->lock, flags);
351 return result;
352}
353
354static const char *__wlp_wss_connect_state[] = { "WLP_WSS_UNCONNECTED",
355 "WLP_WSS_CONNECTED",
356 "WLP_WSS_CONNECT_FAILED",
357};
358
359static const char *wlp_wss_connect_state_str(unsigned id)
360{
361 if (id >= ARRAY_SIZE(__wlp_wss_connect_state))
362 return "unknown WSS connection state";
363 return __wlp_wss_connect_state[id];
364}
365
366/*
367 * View EDA cache from user space
368 *
369 * A debugging feature to give user visibility into the EDA cache. Also
370 * used to display members of WSS to user (called from wlp_wss_members_show())
371 */
372ssize_t wlp_eda_show(struct wlp *wlp, char *buf)
373{
374 ssize_t result = 0;
375 struct wlp_eda_node *entry;
376 unsigned long flags;
377 struct wlp_eda *eda = &wlp->eda;
378 spin_lock_irqsave(&eda->lock, flags);
379 result = scnprintf(buf, PAGE_SIZE, "#eth_addr dev_addr wss_ptr "
380 "tag state virt_addr\n");
381 list_for_each_entry(entry, &eda->cache, list_node) {
382 result += scnprintf(buf + result, PAGE_SIZE - result,
383 "%02x:%02x:%02x:%02x:%02x:%02x %02x:%02x "
384 "%p 0x%02x %s "
385 "%02x:%02x:%02x:%02x:%02x:%02x\n",
386 entry->eth_addr[0], entry->eth_addr[1],
387 entry->eth_addr[2], entry->eth_addr[3],
388 entry->eth_addr[4], entry->eth_addr[5],
389 entry->dev_addr.data[1],
390 entry->dev_addr.data[0], entry->wss,
391 entry->tag,
392 wlp_wss_connect_state_str(entry->state),
393 entry->virt_addr[0], entry->virt_addr[1],
394 entry->virt_addr[2], entry->virt_addr[3],
395 entry->virt_addr[4], entry->virt_addr[5]);
396 if (result >= PAGE_SIZE)
397 break;
398 }
399 spin_unlock_irqrestore(&eda->lock, flags);
400 return result;
401}
402EXPORT_SYMBOL_GPL(wlp_eda_show);
403
404/*
405 * Add new EDA cache entry based on user input in sysfs
406 *
407 * Should only be used for debugging.
408 *
409 * The WSS is assumed to be the only WSS supported. This needs to be
410 * redesigned when we support more than one WSS.
411 */
412ssize_t wlp_eda_store(struct wlp *wlp, const char *buf, size_t size)
413{
414 ssize_t result;
415 struct wlp_eda *eda = &wlp->eda;
416 u8 eth_addr[6];
417 struct uwb_dev_addr dev_addr;
418 u8 tag;
419 unsigned state;
420
421 result = sscanf(buf, "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx "
422 "%02hhx:%02hhx %02hhx %u\n",
423 &eth_addr[0], &eth_addr[1],
424 &eth_addr[2], &eth_addr[3],
425 &eth_addr[4], &eth_addr[5],
426 &dev_addr.data[1], &dev_addr.data[0], &tag, &state);
427 switch (result) {
428 case 6: /* no dev addr specified -- remove entry NOT IMPLEMENTED */
429 /*result = wlp_eda_rm(eda, eth_addr, &dev_addr);*/
430 result = -ENOSYS;
431 break;
432 case 10:
433 state = state >= 1 ? 1 : 0;
434 result = wlp_eda_create_node(eda, eth_addr, &dev_addr);
435 if (result < 0 && result != -EEXIST)
436 goto error;
437 /* Set virtual addr to be same as MAC */
438 result = wlp_eda_update_node(eda, &dev_addr, &wlp->wss,
439 eth_addr, tag, state);
440 if (result < 0)
441 goto error;
442 break;
443 default: /* bad format */
444 result = -EINVAL;
445 }
446error:
447 return result < 0 ? result : size;
448}
449EXPORT_SYMBOL_GPL(wlp_eda_store);