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initial commit with v2.6.9
[linux-2.6.9-moxart.git] / arch / um / drivers / line.c
blobc6b77fccd2c4179700b6f17a804f24e5244e8691
1 /*
2 * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6 #include "linux/sched.h"
7 #include "linux/slab.h"
8 #include "linux/list.h"
9 #include "linux/interrupt.h"
10 #include "linux/devfs_fs_kernel.h"
11 #include "asm/uaccess.h"
12 #include "chan_kern.h"
13 #include "irq_user.h"
14 #include "line.h"
15 #include "kern.h"
16 #include "user_util.h"
17 #include "kern_util.h"
18 #include "os.h"
19 #include "irq_kern.h"
20
21 #define LINE_BUFSIZE 4096
22
23 static irqreturn_t line_interrupt(int irq, void *data, struct pt_regs *unused)
24 {
25 struct line *dev = data;
26
27 if(dev->count > 0)
28 chan_interrupt(&dev->chan_list, &dev->task, dev->tty, irq,
29 dev);
30 return IRQ_HANDLED;
31 }
32
33 static void line_timer_cb(void *arg)
34 {
35 struct line *dev = arg;
36
37 line_interrupt(dev->driver->read_irq, dev, NULL);
38 }
39
40 static int write_room(struct line *dev)
41 {
42 int n;
43
44 if(dev->buffer == NULL) return(LINE_BUFSIZE - 1);
45
46 n = dev->head - dev->tail;
47 if(n <= 0) n = LINE_BUFSIZE + n;
48 return(n - 1);
49 }
50
51 static int buffer_data(struct line *line, const char *buf, int len)
52 {
53 int end, room;
54
55 if(line->buffer == NULL){
56 line->buffer = kmalloc(LINE_BUFSIZE, GFP_ATOMIC);
57 if(line->buffer == NULL){
58 printk("buffer_data - atomic allocation failed\n");
59 return(0);
60 }
61 line->head = line->buffer;
62 line->tail = line->buffer;
63 }
64
65 room = write_room(line);
66 len = (len > room) ? room : len;
67
68 end = line->buffer + LINE_BUFSIZE - line->tail;
69 if(len < end){
70 memcpy(line->tail, buf, len);
71 line->tail += len;
72 }
73 else {
74 memcpy(line->tail, buf, end);
75 buf += end;
76 memcpy(line->buffer, buf, len - end);
77 line->tail = line->buffer + len - end;
78 }
79
80 return(len);
81 }
82
83 static int flush_buffer(struct line *line)
84 {
85 int n, count;
86
87 if((line->buffer == NULL) || (line->head == line->tail)) return(1);
88
89 if(line->tail < line->head){
90 count = line->buffer + LINE_BUFSIZE - line->head;
91 n = write_chan(&line->chan_list, line->head, count,
92 line->driver->write_irq);
93 if(n < 0) return(n);
94 if(n == count) line->head = line->buffer;
95 else {
96 line->head += n;
97 return(0);
98 }
99 }
100
101 count = line->tail - line->head;
102 n = write_chan(&line->chan_list, line->head, count,
103 line->driver->write_irq);
104 if(n < 0) return(n);
105
106 line->head += n;
107 return(line->head == line->tail);
108 }
109
110 int line_write(struct line *lines, struct tty_struct *tty, int from_user,
111 const char *buf, int len)
112 {
113 struct line *line;
114 char *new;
115 unsigned long flags;
116 int n, err, i, ret = 0;
117
118 if(tty->stopped) return 0;
119
120 if(from_user){
121 new = kmalloc(len, GFP_KERNEL);
122 if(new == NULL)
123 return(0);
124 n = copy_from_user(new, buf, len);
125 buf = new;
126 if(n == len){
127 len = -EFAULT;
128 goto out_free;
129 }
130
131 len -= n;
132 }
133
134 i = tty->index;
135 line = &lines[i];
136
137 down(&line->sem);
138 if(line->head != line->tail){
139 local_irq_save(flags);
140 ret += buffer_data(line, buf, len);
141 err = flush_buffer(line);
142 local_irq_restore(flags);
143 if(err <= 0)
144 goto out_up;
145 }
146 else {
147 n = write_chan(&line->chan_list, buf, len,
148 line->driver->write_irq);
149 if(n < 0){
150 ret = n;
151 goto out_up;
152 }
153
154 len -= n;
155 ret += n;
156 if(len > 0)
157 ret += buffer_data(line, buf + n, len);
158 }
159 out_up:
160 up(&line->sem);
161 out_free:
162 if(from_user)
163 kfree(buf);
164 return(ret);
165 }
166
167 static irqreturn_t line_write_interrupt(int irq, void *data,
168 struct pt_regs *unused)
169 {
170 struct line *dev = data;
171 struct tty_struct *tty = dev->tty;
172 int err;
173
174 err = flush_buffer(dev);
175 if(err == 0)
176 return(IRQ_NONE);
177 else if(err < 0){
178 dev->head = dev->buffer;
179 dev->tail = dev->buffer;
180 }
181
182 if(tty == NULL)
183 return(IRQ_NONE);
184
185 if(test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) &&
186 (tty->ldisc.write_wakeup != NULL))
187 (tty->ldisc.write_wakeup)(tty);
188
189 /* BLOCKING mode
190 * In blocking mode, everything sleeps on tty->write_wait.
191 * Sleeping in the console driver would break non-blocking
192 * writes.
193 */
194
195 if(waitqueue_active(&tty->write_wait))
196 wake_up_interruptible(&tty->write_wait);
197 return(IRQ_HANDLED);
198 }
199
200 int line_setup_irq(int fd, int input, int output, void *data)
201 {
202 struct line *line = data;
203 struct line_driver *driver = line->driver;
204 int err = 0, flags = SA_INTERRUPT | SA_SHIRQ | SA_SAMPLE_RANDOM;
205
206 if(input) err = um_request_irq(driver->read_irq, fd, IRQ_READ,
207 line_interrupt, flags,
208 driver->read_irq_name, line);
209 if(err) return(err);
210 if(output) err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
211 line_write_interrupt, flags,
212 driver->write_irq_name, line);
213 line->have_irq = 1;
214 return(err);
215 }
216
217 void line_disable(struct line *line, int current_irq)
218 {
219 if(!line->have_irq) return;
220
221 if(line->driver->read_irq == current_irq)
222 free_irq_later(line->driver->read_irq, line);
223 else
224 free_irq(line->driver->read_irq, line);
225
226 if(line->driver->write_irq == current_irq)
227 free_irq_later(line->driver->write_irq, line);
228 else
229 free_irq(line->driver->write_irq, line);
230
231 line->have_irq = 0;
232 }
233
234 int line_open(struct line *lines, struct tty_struct *tty,
235 struct chan_opts *opts)
236 {
237 struct line *line;
238 int n, err = 0;
239
240 if(tty == NULL) n = 0;
241 else n = tty->index;
242 line = &lines[n];
243
244 down(&line->sem);
245 if(line->count == 0){
246 if(!line->valid){
247 err = -ENODEV;
248 goto out;
249 }
250 if(list_empty(&line->chan_list)){
251 err = parse_chan_pair(line->init_str, &line->chan_list,
252 line->init_pri, n, opts);
253 if(err) goto out;
254 err = open_chan(&line->chan_list);
255 if(err) goto out;
256 }
257 enable_chan(&line->chan_list, line);
258 INIT_WORK(&line->task, line_timer_cb, line);
259 }
260
261 if(!line->sigio){
262 chan_enable_winch(&line->chan_list, line);
263 line->sigio = 1;
264 }
265
266 /* This is outside the if because the initial console is opened
267 * with tty == NULL
268 */
269 line->tty = tty;
270
271 if(tty != NULL){
272 tty->driver_data = line;
273 chan_window_size(&line->chan_list, &tty->winsize.ws_row,
274 &tty->winsize.ws_col);
275 }
276
277 line->count++;
278 out:
279 up(&line->sem);
280 return(err);
281 }
282
283 void line_close(struct line *lines, struct tty_struct *tty)
284 {
285 struct line *line;
286 int n;
287
288 if(tty == NULL) n = 0;
289 else n = tty->index;
290 line = &lines[n];
291
292 down(&line->sem);
293 line->count--;
294
295 /* I don't like this, but I can't think of anything better. What's
296 * going on is that the tty is in the process of being closed for
297 * the last time. Its count hasn't been dropped yet, so it's still
298 * at 1. This may happen when line->count != 0 because of the initial
299 * console open (without a tty) bumping it up to 1.
300 */
301 if((line->tty != NULL) && (line->tty->count == 1))
302 line->tty = NULL;
303 if(line->count == 0)
304 line_disable(line, -1);
305 up(&line->sem);
306 }
307
308 void close_lines(struct line *lines, int nlines)
309 {
310 int i;
311
312 for(i = 0; i < nlines; i++)
313 close_chan(&lines[i].chan_list);
314 }
315
316 int line_setup(struct line *lines, int num, char *init, int all_allowed)
317 {
318 int i, n;
319 char *end;
320
321 if(*init == '=') n = -1;
322 else {
323 n = simple_strtoul(init, &end, 0);
324 if(*end != '='){
325 printk(KERN_ERR "line_setup failed to parse \"%s\"\n",
326 init);
327 return(0);
328 }
329 init = end;
330 }
331 init++;
332 if((n >= 0) && (n >= num)){
333 printk("line_setup - %d out of range ((0 ... %d) allowed)\n",
334 n, num - 1);
335 return(0);
336 }
337 else if(n >= 0){
338 if(lines[n].count > 0){
339 printk("line_setup - device %d is open\n", n);
340 return(0);
341 }
342 if(lines[n].init_pri <= INIT_ONE){
343 lines[n].init_pri = INIT_ONE;
344 if(!strcmp(init, "none")) lines[n].valid = 0;
345 else {
346 lines[n].init_str = init;
347 lines[n].valid = 1;
348 }
349 }
350 }
351 else if(!all_allowed){
352 printk("line_setup - can't configure all devices from "
353 "mconsole\n");
354 return(0);
355 }
356 else {
357 for(i = 0; i < num; i++){
358 if(lines[i].init_pri <= INIT_ALL){
359 lines[i].init_pri = INIT_ALL;
360 if(!strcmp(init, "none")) lines[i].valid = 0;
361 else {
362 lines[i].init_str = init;
363 lines[i].valid = 1;
364 }
365 }
366 }
367 }
368 return(1);
369 }
370
371 int line_config(struct line *lines, int num, char *str)
372 {
373 char *new = uml_strdup(str);
374
375 if(new == NULL){
376 printk("line_config - uml_strdup failed\n");
377 return(-ENOMEM);
378 }
379 return(!line_setup(lines, num, new, 0));
380 }
381
382 int line_get_config(char *name, struct line *lines, int num, char *str,
383 int size, char **error_out)
384 {
385 struct line *line;
386 char *end;
387 int dev, n = 0;
388
389 dev = simple_strtoul(name, &end, 0);
390 if((*end != '\0') || (end == name)){
391 *error_out = "line_get_config failed to parse device number";
392 return(0);
393 }
394
395 if((dev < 0) || (dev >= num)){
396 *error_out = "device number of of range";
397 return(0);
398 }
399
400 line = &lines[dev];
401
402 down(&line->sem);
403 if(!line->valid)
404 CONFIG_CHUNK(str, size, n, "none", 1);
405 else if(line->count == 0)
406 CONFIG_CHUNK(str, size, n, line->init_str, 1);
407 else n = chan_config_string(&line->chan_list, str, size, error_out);
408 up(&line->sem);
409
410 return(n);
411 }
412
413 int line_remove(struct line *lines, int num, char *str)
414 {
415 char config[sizeof("conxxxx=none\0")];
416
417 sprintf(config, "%s=none", str);
418 return(!line_setup(lines, num, config, 0));
419 }
420
421 int line_write_room(struct tty_struct *tty)
422 {
423 struct line *dev = tty->driver_data;
424
425 return(write_room(dev));
426 }
427
428 struct tty_driver *line_register_devfs(struct lines *set,
429 struct line_driver *line_driver,
430 struct tty_operations *ops, struct line *lines,
431 int nlines)
432 {
433 int err, i;
434 char *from, *to;
435 struct tty_driver *driver = alloc_tty_driver(nlines);
436
437 if (!driver)
438 return NULL;
439
440 driver->driver_name = line_driver->name;
441 driver->name = line_driver->device_name;
442 driver->devfs_name = line_driver->devfs_name;
443 driver->major = line_driver->major;
444 driver->minor_start = line_driver->minor_start;
445 driver->type = line_driver->type;
446 driver->subtype = line_driver->subtype;
447 driver->flags = TTY_DRIVER_REAL_RAW;
448 driver->init_termios = tty_std_termios;
449 tty_set_operations(driver, ops);
450
451 if (tty_register_driver(driver))
452 panic("line_register_devfs : Couldn't register driver\n");
453
454 from = line_driver->symlink_from;
455 to = line_driver->symlink_to;
456 err = devfs_mk_symlink(from, to);
457 if(err) printk("Symlink creation from /dev/%s to /dev/%s "
458 "returned %d\n", from, to, err);
459
460 for(i = 0; i < nlines; i++){
461 if(!lines[i].valid)
462 tty_unregister_device(driver, i);
463 }
464
465 mconsole_register_dev(&line_driver->mc);
466 return driver;
467 }
468
469 void lines_init(struct line *lines, int nlines)
470 {
471 struct line *line;
472 int i;
473
474 for(i = 0; i < nlines; i++){
475 line = &lines[i];
476 INIT_LIST_HEAD(&line->chan_list);
477 sema_init(&line->sem, 1);
478 if(line->init_str != NULL){
479 line->init_str = uml_strdup(line->init_str);
480 if(line->init_str == NULL)
481 printk("lines_init - uml_strdup returned "
482 "NULL\n");
483 }
484 }
485 }
486
487 struct winch {
488 struct list_head list;
489 int fd;
490 int tty_fd;
491 int pid;
492 struct line *line;
493 };
494
495 irqreturn_t winch_interrupt(int irq, void *data, struct pt_regs *unused)
496 {
497 struct winch *winch = data;
498 struct tty_struct *tty;
499 int err;
500 char c;
501
502 if(winch->fd != -1){
503 err = generic_read(winch->fd, &c, NULL);
504 if(err < 0){
505 if(err != -EAGAIN){
506 printk("winch_interrupt : read failed, "
507 "errno = %d\n", -err);
508 printk("fd %d is losing SIGWINCH support\n",
509 winch->tty_fd);
510 return(IRQ_HANDLED);
511 }
512 goto out;
513 }
514 }
515 tty = winch->line->tty;
516 if(tty != NULL){
517 chan_window_size(&winch->line->chan_list,
518 &tty->winsize.ws_row,
519 &tty->winsize.ws_col);
520 kill_pg(tty->pgrp, SIGWINCH, 1);
521 }
522 out:
523 if(winch->fd != -1)
524 reactivate_fd(winch->fd, WINCH_IRQ);
525 return(IRQ_HANDLED);
526 }
527
528 DECLARE_MUTEX(winch_handler_sem);
529 LIST_HEAD(winch_handlers);
530
531 void register_winch_irq(int fd, int tty_fd, int pid, void *line)
532 {
533 struct winch *winch;
534
535 down(&winch_handler_sem);
536 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
537 if(winch == NULL){
538 printk("register_winch_irq - kmalloc failed\n");
539 goto out;
540 }
541 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
542 .fd = fd,
543 .tty_fd = tty_fd,
544 .pid = pid,
545 .line = line });
546 list_add(&winch->list, &winch_handlers);
547 if(um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
548 SA_INTERRUPT | SA_SHIRQ | SA_SAMPLE_RANDOM,
549 "winch", winch) < 0)
550 printk("register_winch_irq - failed to register IRQ\n");
551 out:
552 up(&winch_handler_sem);
553 }
554
555 static void winch_cleanup(void)
556 {
557 struct list_head *ele;
558 struct winch *winch;
559
560 list_for_each(ele, &winch_handlers){
561 winch = list_entry(ele, struct winch, list);
562 if(winch->fd != -1){
563 deactivate_fd(winch->fd, WINCH_IRQ);
564 os_close_file(winch->fd);
565 }
566 if(winch->pid != -1)
567 os_kill_process(winch->pid, 1);
568 }
569 }
570
571 __uml_exitcall(winch_cleanup);
572
573 char *add_xterm_umid(char *base)
574 {
575 char *umid, *title;
576 int len;
577
578 umid = get_umid(1);
579 if(umid == NULL) return(base);
580
581 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
582 title = kmalloc(len, GFP_KERNEL);
583 if(title == NULL){
584 printk("Failed to allocate buffer for xterm title\n");
585 return(base);
586 }
587
588 snprintf(title, len, "%s (%s)", base, umid);
589 return(title);
590 }
591
592 /*
593 * Overrides for Emacs so that we follow Linus's tabbing style.
594 * Emacs will notice this stuff at the end of the file and automatically
595 * adjust the settings for this buffer only. This must remain at the end
596 * of the file.
597 * ---------------------------------------------------------------------------
598 * Local variables:
599 * c-file-style: "linux"
600 * End:
601 */
MOXA 2.6.9 from sdlinux-moxaart.tgz