Revert "Fix very high interrupt rate for IRQ8 (rtc) unless pnpacpi=off"
[pv_ops_mirror.git] / net / irda / discovery.c
blob80c33f408e3fc2ccee1059d6141728cda89d1a27
1 /*********************************************************************
3 * Filename: discovery.c
4 * Version: 0.1
5 * Description: Routines for handling discoveries at the IrLMP layer
6 * Status: Experimental.
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Tue Apr 6 15:33:50 1999
9 * Modified at: Sat Oct 9 17:11:31 1999
10 * Modified by: Dag Brattli <dagb@cs.uit.no>
11 * Modified at: Fri May 28 3:11 CST 1999
12 * Modified by: Horst von Brand <vonbrand@sleipnir.valparaiso.cl>
14 * Copyright (c) 1999 Dag Brattli, All Rights Reserved.
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of
19 * the License, or (at your option) any later version.
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29 * MA 02111-1307 USA
31 ********************************************************************/
33 #include <linux/string.h>
34 #include <linux/socket.h>
35 #include <linux/fs.h>
36 #include <linux/seq_file.h>
38 #include <net/irda/irda.h>
39 #include <net/irda/irlmp.h>
41 #include <net/irda/discovery.h>
44 * Function irlmp_add_discovery (cachelog, discovery)
46 * Add a new discovery to the cachelog, and remove any old discoveries
47 * from the same device
49 * Note : we try to preserve the time this device was *first* discovered
50 * (as opposed to the time of last discovery used for cleanup). This is
51 * used by clients waiting for discovery events to tell if the device
52 * discovered is "new" or just the same old one. They can't rely there
53 * on a binary flag (new/old), because not all discovery events are
54 * propagated to them, and they might not always listen, so they would
55 * miss some new devices popping up...
56 * Jean II
58 void irlmp_add_discovery(hashbin_t *cachelog, discovery_t *new)
60 discovery_t *discovery, *node;
61 unsigned long flags;
63 /* Set time of first discovery if node is new (see below) */
64 new->firststamp = new->timestamp;
66 spin_lock_irqsave(&cachelog->hb_spinlock, flags);
69 * Remove all discoveries of devices that has previously been
70 * discovered on the same link with the same name (info), or the
71 * same daddr. We do this since some devices (mostly PDAs) change
72 * their device address between every discovery.
74 discovery = (discovery_t *) hashbin_get_first(cachelog);
75 while (discovery != NULL ) {
76 node = discovery;
78 /* Be sure to stay one item ahead */
79 discovery = (discovery_t *) hashbin_get_next(cachelog);
81 if ((node->data.saddr == new->data.saddr) &&
82 ((node->data.daddr == new->data.daddr) ||
83 (strcmp(node->data.info, new->data.info) == 0)))
85 /* This discovery is a previous discovery
86 * from the same device, so just remove it
88 hashbin_remove_this(cachelog, (irda_queue_t *) node);
89 /* Check if hints bits are unchanged */
90 if(u16ho(node->data.hints) == u16ho(new->data.hints))
91 /* Set time of first discovery for this node */
92 new->firststamp = node->firststamp;
93 kfree(node);
97 /* Insert the new and updated version */
98 hashbin_insert(cachelog, (irda_queue_t *) new, new->data.daddr, NULL);
100 spin_unlock_irqrestore(&cachelog->hb_spinlock, flags);
104 * Function irlmp_add_discovery_log (cachelog, log)
106 * Merge a disovery log into the cachelog.
109 void irlmp_add_discovery_log(hashbin_t *cachelog, hashbin_t *log)
111 discovery_t *discovery;
113 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
116 * If log is missing this means that IrLAP was unable to perform the
117 * discovery, so restart discovery again with just the half timeout
118 * of the normal one.
120 /* Well... It means that there was nobody out there - Jean II */
121 if (log == NULL) {
122 /* irlmp_start_discovery_timer(irlmp, 150); */
123 return;
127 * Locking : we are the only owner of this discovery log, so
128 * no need to lock it.
129 * We just need to lock the global log in irlmp_add_discovery().
131 discovery = (discovery_t *) hashbin_remove_first(log);
132 while (discovery != NULL) {
133 irlmp_add_discovery(cachelog, discovery);
135 discovery = (discovery_t *) hashbin_remove_first(log);
138 /* Delete the now empty log */
139 hashbin_delete(log, (FREE_FUNC) kfree);
143 * Function irlmp_expire_discoveries (log, saddr, force)
145 * Go through all discoveries and expire all that has stayed too long
147 * Note : this assume that IrLAP won't change its saddr, which
148 * currently is a valid assumption...
150 void irlmp_expire_discoveries(hashbin_t *log, __u32 saddr, int force)
152 discovery_t * discovery;
153 discovery_t * curr;
154 unsigned long flags;
155 discinfo_t * buffer = NULL;
156 int n; /* Size of the full log */
157 int i = 0; /* How many we expired */
159 IRDA_ASSERT(log != NULL, return;);
160 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
162 spin_lock_irqsave(&log->hb_spinlock, flags);
164 discovery = (discovery_t *) hashbin_get_first(log);
165 while (discovery != NULL) {
166 /* Be sure to be one item ahead */
167 curr = discovery;
168 discovery = (discovery_t *) hashbin_get_next(log);
170 /* Test if it's time to expire this discovery */
171 if ((curr->data.saddr == saddr) &&
172 (force ||
173 ((jiffies - curr->timestamp) > DISCOVERY_EXPIRE_TIMEOUT)))
175 /* Create buffer as needed.
176 * As this function get called a lot and most time
177 * we don't have anything to put in the log (we are
178 * quite picky), we can save a lot of overhead
179 * by not calling kmalloc. Jean II */
180 if(buffer == NULL) {
181 /* Create the client specific buffer */
182 n = HASHBIN_GET_SIZE(log);
183 buffer = kmalloc(n * sizeof(struct irda_device_info), GFP_ATOMIC);
184 if (buffer == NULL) {
185 spin_unlock_irqrestore(&log->hb_spinlock, flags);
186 return;
191 /* Copy discovery information */
192 memcpy(&(buffer[i]), &(curr->data),
193 sizeof(discinfo_t));
194 i++;
196 /* Remove it from the log */
197 curr = hashbin_remove_this(log, (irda_queue_t *) curr);
198 kfree(curr);
202 /* Drop the spinlock before calling the higher layers, as
203 * we can't guarantee they won't call us back and create a
204 * deadlock. We will work on our own private data, so we
205 * don't care to be interrupted. - Jean II */
206 spin_unlock_irqrestore(&log->hb_spinlock, flags);
208 if(buffer == NULL)
209 return;
211 /* Tell IrLMP and registered clients about it */
212 irlmp_discovery_expiry(buffer, i);
214 /* Free up our buffer */
215 kfree(buffer);
218 #if 0
220 * Function irlmp_dump_discoveries (log)
222 * Print out all discoveries in log
225 void irlmp_dump_discoveries(hashbin_t *log)
227 discovery_t *discovery;
229 IRDA_ASSERT(log != NULL, return;);
231 discovery = (discovery_t *) hashbin_get_first(log);
232 while (discovery != NULL) {
233 IRDA_DEBUG(0, "Discovery:\n");
234 IRDA_DEBUG(0, " daddr=%08x\n", discovery->data.daddr);
235 IRDA_DEBUG(0, " saddr=%08x\n", discovery->data.saddr);
236 IRDA_DEBUG(0, " nickname=%s\n", discovery->data.info);
238 discovery = (discovery_t *) hashbin_get_next(log);
241 #endif
244 * Function irlmp_copy_discoveries (log, pn, mask)
246 * Copy all discoveries in a buffer
248 * This function implement a safe way for lmp clients to access the
249 * discovery log. The basic problem is that we don't want the log
250 * to change (add/remove) while the client is reading it. If the
251 * lmp client manipulate directly the hashbin, he is sure to get
252 * into troubles...
253 * The idea is that we copy all the current discovery log in a buffer
254 * which is specific to the client and pass this copy to him. As we
255 * do this operation with the spinlock grabbed, we are safe...
256 * Note : we don't want those clients to grab the spinlock, because
257 * we have no control on how long they will hold it...
258 * Note : we choose to copy the log in "struct irda_device_info" to
259 * save space...
260 * Note : the client must kfree himself() the log...
261 * Jean II
263 struct irda_device_info *irlmp_copy_discoveries(hashbin_t *log, int *pn,
264 __u16 mask, int old_entries)
266 discovery_t * discovery;
267 unsigned long flags;
268 discinfo_t * buffer = NULL;
269 int j_timeout = (sysctl_discovery_timeout * HZ);
270 int n; /* Size of the full log */
271 int i = 0; /* How many we picked */
273 IRDA_ASSERT(pn != NULL, return NULL;);
274 IRDA_ASSERT(log != NULL, return NULL;);
276 /* Save spin lock */
277 spin_lock_irqsave(&log->hb_spinlock, flags);
279 discovery = (discovery_t *) hashbin_get_first(log);
280 while (discovery != NULL) {
281 /* Mask out the ones we don't want :
282 * We want to match the discovery mask, and to get only
283 * the most recent one (unless we want old ones) */
284 if ((u16ho(discovery->data.hints) & mask) &&
285 ((old_entries) ||
286 ((jiffies - discovery->firststamp) < j_timeout)) ) {
287 /* Create buffer as needed.
288 * As this function get called a lot and most time
289 * we don't have anything to put in the log (we are
290 * quite picky), we can save a lot of overhead
291 * by not calling kmalloc. Jean II */
292 if(buffer == NULL) {
293 /* Create the client specific buffer */
294 n = HASHBIN_GET_SIZE(log);
295 buffer = kmalloc(n * sizeof(struct irda_device_info), GFP_ATOMIC);
296 if (buffer == NULL) {
297 spin_unlock_irqrestore(&log->hb_spinlock, flags);
298 return NULL;
303 /* Copy discovery information */
304 memcpy(&(buffer[i]), &(discovery->data),
305 sizeof(discinfo_t));
306 i++;
308 discovery = (discovery_t *) hashbin_get_next(log);
311 spin_unlock_irqrestore(&log->hb_spinlock, flags);
313 /* Get the actual number of device in the buffer and return */
314 *pn = i;
315 return(buffer);
318 #ifdef CONFIG_PROC_FS
319 static inline discovery_t *discovery_seq_idx(loff_t pos)
322 discovery_t *discovery;
324 for (discovery = (discovery_t *) hashbin_get_first(irlmp->cachelog);
325 discovery != NULL;
326 discovery = (discovery_t *) hashbin_get_next(irlmp->cachelog)) {
327 if (pos-- == 0)
328 break;
331 return discovery;
334 static void *discovery_seq_start(struct seq_file *seq, loff_t *pos)
336 spin_lock_irq(&irlmp->cachelog->hb_spinlock);
337 return *pos ? discovery_seq_idx(*pos - 1) : SEQ_START_TOKEN;
340 static void *discovery_seq_next(struct seq_file *seq, void *v, loff_t *pos)
342 ++*pos;
343 return (v == SEQ_START_TOKEN)
344 ? (void *) hashbin_get_first(irlmp->cachelog)
345 : (void *) hashbin_get_next(irlmp->cachelog);
348 static void discovery_seq_stop(struct seq_file *seq, void *v)
350 spin_unlock_irq(&irlmp->cachelog->hb_spinlock);
353 static int discovery_seq_show(struct seq_file *seq, void *v)
355 if (v == SEQ_START_TOKEN)
356 seq_puts(seq, "IrLMP: Discovery log:\n\n");
357 else {
358 const discovery_t *discovery = v;
360 seq_printf(seq, "nickname: %s, hint: 0x%02x%02x",
361 discovery->data.info,
362 discovery->data.hints[0],
363 discovery->data.hints[1]);
364 #if 0
365 if ( discovery->data.hints[0] & HINT_PNP)
366 seq_puts(seq, "PnP Compatible ");
367 if ( discovery->data.hints[0] & HINT_PDA)
368 seq_puts(seq, "PDA/Palmtop ");
369 if ( discovery->data.hints[0] & HINT_COMPUTER)
370 seq_puts(seq, "Computer ");
371 if ( discovery->data.hints[0] & HINT_PRINTER)
372 seq_puts(seq, "Printer ");
373 if ( discovery->data.hints[0] & HINT_MODEM)
374 seq_puts(seq, "Modem ");
375 if ( discovery->data.hints[0] & HINT_FAX)
376 seq_puts(seq, "Fax ");
377 if ( discovery->data.hints[0] & HINT_LAN)
378 seq_puts(seq, "LAN Access ");
380 if ( discovery->data.hints[1] & HINT_TELEPHONY)
381 seq_puts(seq, "Telephony ");
382 if ( discovery->data.hints[1] & HINT_FILE_SERVER)
383 seq_puts(seq, "File Server ");
384 if ( discovery->data.hints[1] & HINT_COMM)
385 seq_puts(seq, "IrCOMM ");
386 if ( discovery->data.hints[1] & HINT_OBEX)
387 seq_puts(seq, "IrOBEX ");
388 #endif
389 seq_printf(seq,", saddr: 0x%08x, daddr: 0x%08x\n\n",
390 discovery->data.saddr,
391 discovery->data.daddr);
393 seq_putc(seq, '\n');
395 return 0;
398 static const struct seq_operations discovery_seq_ops = {
399 .start = discovery_seq_start,
400 .next = discovery_seq_next,
401 .stop = discovery_seq_stop,
402 .show = discovery_seq_show,
405 static int discovery_seq_open(struct inode *inode, struct file *file)
407 IRDA_ASSERT(irlmp != NULL, return -EINVAL;);
409 return seq_open(file, &discovery_seq_ops);
412 const struct file_operations discovery_seq_fops = {
413 .owner = THIS_MODULE,
414 .open = discovery_seq_open,
415 .read = seq_read,
416 .llseek = seq_lseek,
417 .release = seq_release,
419 #endif