1 /* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
3 * Linux driver for HYSDN cards, /proc/net filesystem log functions.
5 * Author Werner Cornelius (werner@titro.de) for Hypercope GmbH
6 * Copyright 1999 by Werner Cornelius (werner@titro.de)
8 * This software may be used and distributed according to the terms
9 * of the GNU General Public License, incorporated herein by reference.
13 #include <linux/module.h>
14 #include <linux/poll.h>
15 #include <linux/proc_fs.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/mutex.h>
19 #include <linux/kernel.h>
21 #include "hysdn_defs.h"
23 /* the proc subdir for the interface is defined in the procconf module */
24 extern struct proc_dir_entry *hysdn_proc_entry;
26 static DEFINE_MUTEX(hysdn_log_mutex);
27 static void put_log_buffer(hysdn_card *card, char *cp);
29 /*************************************************/
30 /* structure keeping ascii log for device output */
31 /*************************************************/
33 struct log_data *next;
34 unsigned long usage_cnt;/* number of files still to work */
35 void *proc_ctrl; /* pointer to own control procdata structure */
36 char log_start[2]; /* log string start (final len aligned by size) */
39 /**********************************************/
40 /* structure holding proc entrys for one card */
41 /**********************************************/
43 struct proc_dir_entry *log; /* log entry */
44 char log_name[15]; /* log filename */
45 struct log_data *log_head, *log_tail; /* head and tail for queue */
46 int if_used; /* open count for interface */
47 int volatile del_lock; /* lock for delete operations */
48 unsigned char logtmp[LOG_MAX_LINELEN];
49 wait_queue_head_t rd_queue;
53 /**********************************************/
54 /* log function for cards error log interface */
55 /**********************************************/
57 hysdn_card_errlog(hysdn_card *card, tErrLogEntry *logp, int maxsize)
59 char buf[ERRLOG_TEXT_SIZE + 40];
61 sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
62 put_log_buffer(card, buf); /* output the string */
63 } /* hysdn_card_errlog */
65 /***************************************************/
66 /* Log function using format specifiers for output */
67 /***************************************************/
69 hysdn_addlog(hysdn_card *card, char *fmt, ...)
71 struct procdata *pd = card->proclog;
76 return; /* log structure non existent */
79 cp += sprintf(cp, "HYSDN: card %d ", card->myid);
82 cp += vsprintf(cp, fmt, args);
87 if (card->debug_flags & DEB_OUT_SYSLOG)
88 printk(KERN_INFO "%s", pd->logtmp);
90 put_log_buffer(card, pd->logtmp);
94 /********************************************/
95 /* put an log buffer into the log queue. */
96 /* This buffer will be kept until all files */
97 /* opened for read got the contents. */
98 /* Flushes buffers not longer in use. */
99 /********************************************/
101 put_log_buffer(hysdn_card *card, char *cp)
104 struct procdata *pd = card->proclog;
114 if (pd->if_used <= 0)
115 return; /* no open file for read */
117 if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
118 return; /* no memory */
119 strcpy(ib->log_start, cp); /* set output string */
121 ib->proc_ctrl = pd; /* point to own control structure */
122 spin_lock_irqsave(&card->hysdn_lock, flags);
123 ib->usage_cnt = pd->if_used;
125 pd->log_head = ib; /* new head */
127 pd->log_tail->next = ib; /* follows existing messages */
128 pd->log_tail = ib; /* new tail */
129 i = pd->del_lock++; /* get lock state */
130 spin_unlock_irqrestore(&card->hysdn_lock, flags);
132 /* delete old entrys */
134 while (pd->log_head->next) {
135 if ((pd->log_head->usage_cnt <= 0) &&
136 (pd->log_head->next->usage_cnt <= 0)) {
138 pd->log_head = pd->log_head->next;
142 } /* pd->log_head->next */
143 pd->del_lock--; /* release lock level */
144 wake_up_interruptible(&(pd->rd_queue)); /* announce new entry */
145 } /* put_log_buffer */
148 /******************************/
149 /* file operations and tables */
150 /******************************/
152 /****************************************/
153 /* write log file -> set log level bits */
154 /****************************************/
156 hysdn_log_write(struct file *file, const char __user *buf, size_t count, loff_t *off)
159 unsigned char valbuf[128];
160 hysdn_card *card = file->private_data;
162 if (count > (sizeof(valbuf) - 1))
163 count = sizeof(valbuf) - 1; /* limit length */
164 if (copy_from_user(valbuf, buf, count))
165 return (-EFAULT); /* copy failed */
167 valbuf[count] = 0; /* terminating 0 */
169 rc = kstrtoul(valbuf, 0, &card->debug_flags);
172 hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
174 } /* hysdn_log_write */
180 hysdn_log_read(struct file *file, char __user *buf, size_t count, loff_t *off)
182 struct log_data *inf;
184 struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
185 struct procdata *pd = NULL;
188 if (!*((struct log_data **) file->private_data)) {
189 if (file->f_flags & O_NONBLOCK)
192 /* sorry, but we need to search the card */
198 card = card->next; /* search next entry */
201 interruptible_sleep_on(&(pd->rd_queue));
206 if (!(inf = *((struct log_data **) file->private_data)))
209 inf->usage_cnt--; /* new usage count */
210 file->private_data = &inf->next; /* next structure */
211 if ((len = strlen(inf->log_start)) <= count) {
212 if (copy_to_user(buf, inf->log_start, len))
218 } /* hysdn_log_read */
224 hysdn_log_open(struct inode *ino, struct file *filep)
227 struct procdata *pd = NULL;
230 mutex_lock(&hysdn_log_mutex);
234 if (pd->log == PDE(ino))
236 card = card->next; /* search next entry */
239 mutex_unlock(&hysdn_log_mutex);
240 return (-ENODEV); /* device is unknown/invalid */
242 filep->private_data = card; /* remember our own card */
244 if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
245 /* write only access -> write log level only */
246 } else if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
248 /* read access -> log/debug read */
249 spin_lock_irqsave(&card->hysdn_lock, flags);
252 filep->private_data = &pd->log_tail->next;
254 filep->private_data = &pd->log_head;
255 spin_unlock_irqrestore(&card->hysdn_lock, flags);
256 } else { /* simultaneous read/write access forbidden ! */
257 mutex_unlock(&hysdn_log_mutex);
258 return (-EPERM); /* no permission this time */
260 mutex_unlock(&hysdn_log_mutex);
261 return nonseekable_open(ino, filep);
262 } /* hysdn_log_open */
264 /*******************************************************************************/
265 /* close a cardlog file. If the file has been opened for exclusive write it is */
266 /* assumed as pof data input and the pof loader is noticed about. */
267 /* Otherwise file is handled as log output. In this case the interface usage */
268 /* count is decremented and all buffers are noticed of closing. If this file */
269 /* was the last one to be closed, all buffers are freed. */
270 /*******************************************************************************/
272 hysdn_log_close(struct inode *ino, struct file *filep)
274 struct log_data *inf;
279 mutex_lock(&hysdn_log_mutex);
280 if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
281 /* write only access -> write debug level written */
282 retval = 0; /* success */
284 /* read access -> log/debug read, mark one further file as closed */
287 inf = *((struct log_data **) filep->private_data); /* get first log entry */
289 pd = (struct procdata *) inf->proc_ctrl; /* still entries there */
291 /* no info available -> search card */
295 if (pd->log == PDE(ino))
297 card = card->next; /* search next entry */
300 pd = card->proclog; /* pointer to procfs log */
303 pd->if_used--; /* decrement interface usage count by one */
306 inf->usage_cnt--; /* decrement usage count for buffers */
311 if (pd->if_used <= 0) /* delete buffers if last file closed */
312 while (pd->log_head) {
314 pd->log_head = pd->log_head->next;
318 mutex_unlock(&hysdn_log_mutex);
321 } /* hysdn_log_close */
323 /*************************************************/
324 /* select/poll routine to be able using select() */
325 /*************************************************/
327 hysdn_log_poll(struct file *file, poll_table *wait)
329 unsigned int mask = 0;
330 struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
332 struct procdata *pd = NULL;
334 if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE)
335 return (mask); /* no polling for write supported */
337 /* we need to search the card */
343 card = card->next; /* search next entry */
346 return (mask); /* card not found */
348 poll_wait(file, &(pd->rd_queue), wait);
350 if (*((struct log_data **) file->private_data))
351 mask |= POLLIN | POLLRDNORM;
354 } /* hysdn_log_poll */
356 /**************************************************/
357 /* table for log filesystem functions defined above. */
358 /**************************************************/
359 static const struct file_operations log_fops =
361 .owner = THIS_MODULE,
363 .read = hysdn_log_read,
364 .write = hysdn_log_write,
365 .poll = hysdn_log_poll,
366 .open = hysdn_log_open,
367 .release = hysdn_log_close,
371 /***********************************************************************************/
372 /* hysdn_proclog_init is called when the module is loaded after creating the cards */
374 /***********************************************************************************/
376 hysdn_proclog_init(hysdn_card *card)
380 /* create a cardlog proc entry */
382 if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
383 sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
384 pd->log = proc_create(pd->log_name,
385 S_IFREG | S_IRUGO | S_IWUSR, hysdn_proc_entry,
388 init_waitqueue_head(&(pd->rd_queue));
390 card->proclog = (void *) pd; /* remember procfs structure */
393 } /* hysdn_proclog_init */
395 /************************************************************************************/
396 /* hysdn_proclog_release is called when the module is unloaded and before the cards */
397 /* conf file is released */
398 /* The module counter is assumed to be 0 ! */
399 /************************************************************************************/
401 hysdn_proclog_release(hysdn_card *card)
405 if ((pd = (struct procdata *) card->proclog) != NULL) {
407 remove_proc_entry(pd->log_name, hysdn_proc_entry);
408 kfree(pd); /* release memory */
409 card->proclog = NULL;
411 } /* hysdn_proclog_release */