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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/irqreturn.h>
7#include <linux/kd.h>
8#include <linux/sched/signal.h>
9#include <linux/slab.h>
10
11#include "chan.h"
12#include <irq_kern.h>
13#include <irq_user.h>
14#include <kern_util.h>
15#include <os.h>
16
17#define LINE_BUFSIZE 4096
18
19static irqreturn_t line_interrupt(int irq, void *data)
20{
21 struct chan *chan = data;
22 struct line *line = chan->line;
23
24 if (line)
25 chan_interrupt(line, irq);
26
27 return IRQ_HANDLED;
28}
29
30/*
31 * Returns the free space inside the ring buffer of this line.
32 *
33 * Should be called while holding line->lock (this does not modify data).
34 */
35static unsigned int write_room(struct line *line)
36{
37 int n;
38
39 if (line->buffer == NULL)
40 return LINE_BUFSIZE - 1;
41
42 /* This is for the case where the buffer is wrapped! */
43 n = line->head - line->tail;
44
45 if (n <= 0)
46 n += LINE_BUFSIZE; /* The other case */
47 return n - 1;
48}
49
50unsigned int line_write_room(struct tty_struct *tty)
51{
52 struct line *line = tty->driver_data;
53 unsigned long flags;
54 unsigned int room;
55
56 spin_lock_irqsave(&line->lock, flags);
57 room = write_room(line);
58 spin_unlock_irqrestore(&line->lock, flags);
59
60 return room;
61}
62
63unsigned int line_chars_in_buffer(struct tty_struct *tty)
64{
65 struct line *line = tty->driver_data;
66 unsigned long flags;
67 unsigned int ret;
68
69 spin_lock_irqsave(&line->lock, flags);
70 /* write_room subtracts 1 for the needed NULL, so we readd it.*/
71 ret = LINE_BUFSIZE - (write_room(line) + 1);
72 spin_unlock_irqrestore(&line->lock, flags);
73
74 return ret;
75}
76
77/*
78 * This copies the content of buf into the circular buffer associated with
79 * this line.
80 * The return value is the number of characters actually copied, i.e. the ones
81 * for which there was space: this function is not supposed to ever flush out
82 * the circular buffer.
83 *
84 * Must be called while holding line->lock!
85 */
86static int buffer_data(struct line *line, const char *buf, int len)
87{
88 int end, room;
89
90 if (line->buffer == NULL) {
91 line->buffer = kmalloc(LINE_BUFSIZE, GFP_ATOMIC);
92 if (line->buffer == NULL) {
93 printk(KERN_ERR "buffer_data - atomic allocation "
94 "failed\n");
95 return 0;
96 }
97 line->head = line->buffer;
98 line->tail = line->buffer;
99 }
100
101 room = write_room(line);
102 len = (len > room) ? room : len;
103
104 end = line->buffer + LINE_BUFSIZE - line->tail;
105
106 if (len < end) {
107 memcpy(line->tail, buf, len);
108 line->tail += len;
109 }
110 else {
111 /* The circular buffer is wrapping */
112 memcpy(line->tail, buf, end);
113 buf += end;
114 memcpy(line->buffer, buf, len - end);
115 line->tail = line->buffer + len - end;
116 }
117
118 return len;
119}
120
121/*
122 * Flushes the ring buffer to the output channels. That is, write_chan is
123 * called, passing it line->head as buffer, and an appropriate count.
124 *
125 * On exit, returns 1 when the buffer is empty,
126 * 0 when the buffer is not empty on exit,
127 * and -errno when an error occurred.
128 *
129 * Must be called while holding line->lock!*/
130static int flush_buffer(struct line *line)
131{
132 int n, count;
133
134 if ((line->buffer == NULL) || (line->head == line->tail))
135 return 1;
136
137 if (line->tail < line->head) {
138 /* line->buffer + LINE_BUFSIZE is the end of the buffer! */
139 count = line->buffer + LINE_BUFSIZE - line->head;
140
141 n = write_chan(line->chan_out, line->head, count,
142 line->write_irq);
143 if (n < 0)
144 return n;
145 if (n == count) {
146 /*
147 * We have flushed from ->head to buffer end, now we
148 * must flush only from the beginning to ->tail.
149 */
150 line->head = line->buffer;
151 } else {
152 line->head += n;
153 return 0;
154 }
155 }
156
157 count = line->tail - line->head;
158 n = write_chan(line->chan_out, line->head, count,
159 line->write_irq);
160
161 if (n < 0)
162 return n;
163
164 line->head += n;
165 return line->head == line->tail;
166}
167
168void line_flush_buffer(struct tty_struct *tty)
169{
170 struct line *line = tty->driver_data;
171 unsigned long flags;
172
173 spin_lock_irqsave(&line->lock, flags);
174 flush_buffer(line);
175 spin_unlock_irqrestore(&line->lock, flags);
176}
177
178/*
179 * We map both ->flush_chars and ->put_char (which go in pair) onto
180 * ->flush_buffer and ->write. Hope it's not that bad.
181 */
182void line_flush_chars(struct tty_struct *tty)
183{
184 line_flush_buffer(tty);
185}
186
187int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
188{
189 struct line *line = tty->driver_data;
190 unsigned long flags;
191 int n, ret = 0;
192
193 spin_lock_irqsave(&line->lock, flags);
194 if (line->head != line->tail)
195 ret = buffer_data(line, buf, len);
196 else {
197 n = write_chan(line->chan_out, buf, len,
198 line->write_irq);
199 if (n < 0) {
200 ret = n;
201 goto out_up;
202 }
203
204 len -= n;
205 ret += n;
206 if (len > 0)
207 ret += buffer_data(line, buf + n, len);
208 }
209out_up:
210 spin_unlock_irqrestore(&line->lock, flags);
211 return ret;
212}
213
214void line_throttle(struct tty_struct *tty)
215{
216 struct line *line = tty->driver_data;
217
218 deactivate_chan(line->chan_in, line->read_irq);
219 line->throttled = 1;
220}
221
222void line_unthrottle(struct tty_struct *tty)
223{
224 struct line *line = tty->driver_data;
225
226 line->throttled = 0;
227 chan_interrupt(line, line->read_irq);
228}
229
230static irqreturn_t line_write_interrupt(int irq, void *data)
231{
232 struct chan *chan = data;
233 struct line *line = chan->line;
234 int err;
235
236 /*
237 * Interrupts are disabled here because genirq keep irqs disabled when
238 * calling the action handler.
239 */
240
241 spin_lock(&line->lock);
242 err = flush_buffer(line);
243 if (err == 0) {
244 spin_unlock(&line->lock);
245 return IRQ_NONE;
246 } else if ((err < 0) && (err != -EAGAIN)) {
247 line->head = line->buffer;
248 line->tail = line->buffer;
249 }
250 spin_unlock(&line->lock);
251
252 tty_port_tty_wakeup(&line->port);
253
254 return IRQ_HANDLED;
255}
256
257int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
258{
259 const struct line_driver *driver = line->driver;
260 int err;
261
262 if (input) {
263 err = um_request_irq(UM_IRQ_ALLOC, fd, IRQ_READ,
264 line_interrupt, 0,
265 driver->read_irq_name, data);
266 if (err < 0)
267 return err;
268
269 line->read_irq = err;
270 }
271
272 if (output) {
273 err = um_request_irq(UM_IRQ_ALLOC, fd, IRQ_WRITE,
274 line_write_interrupt, 0,
275 driver->write_irq_name, data);
276 if (err < 0)
277 return err;
278
279 line->write_irq = err;
280 }
281
282 return 0;
283}
284
285static int line_activate(struct tty_port *port, struct tty_struct *tty)
286{
287 int ret;
288 struct line *line = tty->driver_data;
289
290 ret = enable_chan(line);
291 if (ret)
292 return ret;
293
294 if (!line->sigio) {
295 chan_enable_winch(line->chan_out, port);
296 line->sigio = 1;
297 }
298
299 chan_window_size(line, &tty->winsize.ws_row,
300 &tty->winsize.ws_col);
301
302 return 0;
303}
304
305static void unregister_winch(struct tty_struct *tty);
306
307static void line_destruct(struct tty_port *port)
308{
309 struct tty_struct *tty = tty_port_tty_get(port);
310 struct line *line = tty->driver_data;
311
312 if (line->sigio) {
313 unregister_winch(tty);
314 line->sigio = 0;
315 }
316}
317
318static const struct tty_port_operations line_port_ops = {
319 .activate = line_activate,
320 .destruct = line_destruct,
321};
322
323int line_open(struct tty_struct *tty, struct file *filp)
324{
325 struct line *line = tty->driver_data;
326
327 return tty_port_open(&line->port, tty, filp);
328}
329
330int line_install(struct tty_driver *driver, struct tty_struct *tty,
331 struct line *line)
332{
333 int ret;
334
335 ret = tty_standard_install(driver, tty);
336 if (ret)
337 return ret;
338
339 tty->driver_data = line;
340
341 return 0;
342}
343
344void line_close(struct tty_struct *tty, struct file * filp)
345{
346 struct line *line = tty->driver_data;
347
348 tty_port_close(&line->port, tty, filp);
349}
350
351void line_hangup(struct tty_struct *tty)
352{
353 struct line *line = tty->driver_data;
354
355 tty_port_hangup(&line->port);
356}
357
358void close_lines(struct line *lines, int nlines)
359{
360 int i;
361
362 for(i = 0; i < nlines; i++)
363 close_chan(&lines[i]);
364}
365
366int setup_one_line(struct line *lines, int n, char *init,
367 const struct chan_opts *opts, char **error_out)
368{
369 struct line *line = &lines[n];
370 struct tty_driver *driver = line->driver->driver;
371 int err = -EINVAL;
372
373 if (line->port.count) {
374 *error_out = "Device is already open";
375 goto out;
376 }
377
378 if (!strcmp(init, "none")) {
379 if (line->valid) {
380 line->valid = 0;
381 kfree(line->init_str);
382 tty_unregister_device(driver, n);
383 parse_chan_pair(NULL, line, n, opts, error_out);
384 err = 0;
385 }
386 } else {
387 char *new = kstrdup(init, GFP_KERNEL);
388 if (!new) {
389 *error_out = "Failed to allocate memory";
390 return -ENOMEM;
391 }
392 if (line->valid) {
393 tty_unregister_device(driver, n);
394 kfree(line->init_str);
395 }
396 line->init_str = new;
397 line->valid = 1;
398 err = parse_chan_pair(new, line, n, opts, error_out);
399 if (!err) {
400 struct device *d = tty_port_register_device(&line->port,
401 driver, n, NULL);
402 if (IS_ERR(d)) {
403 *error_out = "Failed to register device";
404 err = PTR_ERR(d);
405 parse_chan_pair(NULL, line, n, opts, error_out);
406 }
407 }
408 if (err) {
409 line->init_str = NULL;
410 line->valid = 0;
411 kfree(new);
412 }
413 }
414out:
415 return err;
416}
417
418/*
419 * Common setup code for both startup command line and mconsole initialization.
420 * @lines contains the array (of size @num) to modify;
421 * @init is the setup string;
422 * @error_out is an error string in the case of failure;
423 */
424
425int line_setup(char **conf, unsigned int num, char **def,
426 char *init, char *name)
427{
428 char *error;
429
430 if (*init == '=') {
431 /*
432 * We said con=/ssl= instead of con#=, so we are configuring all
433 * consoles at once.
434 */
435 *def = init + 1;
436 } else {
437 char *end;
438 unsigned n = simple_strtoul(init, &end, 0);
439
440 if (*end != '=') {
441 error = "Couldn't parse device number";
442 goto out;
443 }
444 if (n >= num) {
445 error = "Device number out of range";
446 goto out;
447 }
448 conf[n] = end + 1;
449 }
450 return 0;
451
452out:
453 printk(KERN_ERR "Failed to set up %s with "
454 "configuration string \"%s\" : %s\n", name, init, error);
455 return -EINVAL;
456}
457
458int line_config(struct line *lines, unsigned int num, char *str,
459 const struct chan_opts *opts, char **error_out)
460{
461 char *end;
462 int n;
463
464 if (*str == '=') {
465 *error_out = "Can't configure all devices from mconsole";
466 return -EINVAL;
467 }
468
469 n = simple_strtoul(str, &end, 0);
470 if (*end++ != '=') {
471 *error_out = "Couldn't parse device number";
472 return -EINVAL;
473 }
474 if (n >= num) {
475 *error_out = "Device number out of range";
476 return -EINVAL;
477 }
478
479 return setup_one_line(lines, n, end, opts, error_out);
480}
481
482int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
483 int size, char **error_out)
484{
485 struct line *line;
486 char *end;
487 int dev, n = 0;
488
489 dev = simple_strtoul(name, &end, 0);
490 if ((*end != '\0') || (end == name)) {
491 *error_out = "line_get_config failed to parse device number";
492 return 0;
493 }
494
495 if ((dev < 0) || (dev >= num)) {
496 *error_out = "device number out of range";
497 return 0;
498 }
499
500 line = &lines[dev];
501
502 if (!line->valid)
503 CONFIG_CHUNK(str, size, n, "none", 1);
504 else {
505 struct tty_struct *tty = tty_port_tty_get(&line->port);
506 if (tty == NULL) {
507 CONFIG_CHUNK(str, size, n, line->init_str, 1);
508 } else {
509 n = chan_config_string(line, str, size, error_out);
510 tty_kref_put(tty);
511 }
512 }
513
514 return n;
515}
516
517int line_id(char **str, int *start_out, int *end_out)
518{
519 char *end;
520 int n;
521
522 n = simple_strtoul(*str, &end, 0);
523 if ((*end != '\0') || (end == *str))
524 return -1;
525
526 *str = end;
527 *start_out = n;
528 *end_out = n;
529 return n;
530}
531
532int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
533{
534 if (n >= num) {
535 *error_out = "Device number out of range";
536 return -EINVAL;
537 }
538 return setup_one_line(lines, n, "none", NULL, error_out);
539}
540
541int register_lines(struct line_driver *line_driver,
542 const struct tty_operations *ops,
543 struct line *lines, int nlines)
544{
545 struct tty_driver *driver;
546 int err;
547 int i;
548
549 driver = tty_alloc_driver(nlines, TTY_DRIVER_REAL_RAW |
550 TTY_DRIVER_DYNAMIC_DEV);
551 if (IS_ERR(driver))
552 return PTR_ERR(driver);
553
554 driver->driver_name = line_driver->name;
555 driver->name = line_driver->device_name;
556 driver->major = line_driver->major;
557 driver->minor_start = line_driver->minor_start;
558 driver->type = line_driver->type;
559 driver->subtype = line_driver->subtype;
560 driver->init_termios = tty_std_termios;
561
562 for (i = 0; i < nlines; i++) {
563 tty_port_init(&lines[i].port);
564 lines[i].port.ops = &line_port_ops;
565 spin_lock_init(&lines[i].lock);
566 lines[i].driver = line_driver;
567 INIT_LIST_HEAD(&lines[i].chan_list);
568 }
569 tty_set_operations(driver, ops);
570
571 err = tty_register_driver(driver);
572 if (err) {
573 printk(KERN_ERR "register_lines : can't register %s driver\n",
574 line_driver->name);
575 tty_driver_kref_put(driver);
576 for (i = 0; i < nlines; i++)
577 tty_port_destroy(&lines[i].port);
578 return err;
579 }
580
581 line_driver->driver = driver;
582 mconsole_register_dev(&line_driver->mc);
583 return 0;
584}
585
586static DEFINE_SPINLOCK(winch_handler_lock);
587static LIST_HEAD(winch_handlers);
588
589struct winch {
590 struct list_head list;
591 int fd;
592 int tty_fd;
593 int pid;
594 struct tty_port *port;
595 unsigned long stack;
596 struct work_struct work;
597};
598
599static void __free_winch(struct work_struct *work)
600{
601 struct winch *winch = container_of(work, struct winch, work);
602 um_free_irq(WINCH_IRQ, winch);
603
604 if (winch->pid != -1)
605 os_kill_process(winch->pid, 1);
606 if (winch->stack != 0)
607 free_stack(winch->stack, 0);
608 kfree(winch);
609}
610
611static void free_winch(struct winch *winch)
612{
613 int fd = winch->fd;
614 winch->fd = -1;
615 if (fd != -1)
616 os_close_file(fd);
617 __free_winch(&winch->work);
618}
619
620static irqreturn_t winch_interrupt(int irq, void *data)
621{
622 struct winch *winch = data;
623 struct tty_struct *tty;
624 struct line *line;
625 int fd = winch->fd;
626 int err;
627 char c;
628 struct pid *pgrp;
629
630 if (fd != -1) {
631 err = generic_read(fd, &c, NULL);
632 if (err < 0) {
633 if (err != -EAGAIN) {
634 winch->fd = -1;
635 list_del(&winch->list);
636 os_close_file(fd);
637 printk(KERN_ERR "winch_interrupt : "
638 "read failed, errno = %d\n", -err);
639 printk(KERN_ERR "fd %d is losing SIGWINCH "
640 "support\n", winch->tty_fd);
641 INIT_WORK(&winch->work, __free_winch);
642 schedule_work(&winch->work);
643 return IRQ_HANDLED;
644 }
645 goto out;
646 }
647 }
648 tty = tty_port_tty_get(winch->port);
649 if (tty != NULL) {
650 line = tty->driver_data;
651 if (line != NULL) {
652 chan_window_size(line, &tty->winsize.ws_row,
653 &tty->winsize.ws_col);
654 pgrp = tty_get_pgrp(tty);
655 if (pgrp)
656 kill_pgrp(pgrp, SIGWINCH, 1);
657 put_pid(pgrp);
658 }
659 tty_kref_put(tty);
660 }
661 out:
662 return IRQ_HANDLED;
663}
664
665void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port,
666 unsigned long stack)
667{
668 struct winch *winch;
669
670 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
671 if (winch == NULL) {
672 printk(KERN_ERR "register_winch_irq - kmalloc failed\n");
673 goto cleanup;
674 }
675
676 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
677 .fd = fd,
678 .tty_fd = tty_fd,
679 .pid = pid,
680 .port = port,
681 .stack = stack });
682
683 if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
684 IRQF_SHARED, "winch", winch) < 0) {
685 printk(KERN_ERR "register_winch_irq - failed to register "
686 "IRQ\n");
687 goto out_free;
688 }
689
690 spin_lock(&winch_handler_lock);
691 list_add(&winch->list, &winch_handlers);
692 spin_unlock(&winch_handler_lock);
693
694 return;
695
696 out_free:
697 kfree(winch);
698 cleanup:
699 os_kill_process(pid, 1);
700 os_close_file(fd);
701 if (stack != 0)
702 free_stack(stack, 0);
703}
704
705static void unregister_winch(struct tty_struct *tty)
706{
707 struct list_head *ele, *next;
708 struct winch *winch;
709 struct tty_struct *wtty;
710
711 spin_lock(&winch_handler_lock);
712
713 list_for_each_safe(ele, next, &winch_handlers) {
714 winch = list_entry(ele, struct winch, list);
715 wtty = tty_port_tty_get(winch->port);
716 if (wtty == tty) {
717 list_del(&winch->list);
718 spin_unlock(&winch_handler_lock);
719 free_winch(winch);
720 break;
721 }
722 tty_kref_put(wtty);
723 }
724 spin_unlock(&winch_handler_lock);
725}
726
727static void winch_cleanup(void)
728{
729 struct winch *winch;
730
731 spin_lock(&winch_handler_lock);
732 while ((winch = list_first_entry_or_null(&winch_handlers,
733 struct winch, list))) {
734 list_del(&winch->list);
735 spin_unlock(&winch_handler_lock);
736
737 free_winch(winch);
738
739 spin_lock(&winch_handler_lock);
740 }
741
742 spin_unlock(&winch_handler_lock);
743}
744__uml_exitcall(winch_cleanup);
745
746char *add_xterm_umid(char *base)
747{
748 char *umid, *title;
749 int len;
750
751 umid = get_umid();
752 if (*umid == '\0')
753 return base;
754
755 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
756 title = kmalloc(len, GFP_KERNEL);
757 if (title == NULL) {
758 printk(KERN_ERR "Failed to allocate buffer for xterm title\n");
759 return base;
760 }
761
762 snprintf(title, len, "%s (%s)", base, umid);
763 return title;
764}
1/*
2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/irqreturn.h>
7#include <linux/kd.h>
8#include <linux/sched.h>
9#include <linux/slab.h>
10#include "chan.h"
11#include <irq_kern.h>
12#include <irq_user.h>
13#include <kern_util.h>
14#include <os.h>
15
16#define LINE_BUFSIZE 4096
17
18static irqreturn_t line_interrupt(int irq, void *data)
19{
20 struct chan *chan = data;
21 struct line *line = chan->line;
22
23 if (line)
24 chan_interrupt(line, irq);
25
26 return IRQ_HANDLED;
27}
28
29/*
30 * Returns the free space inside the ring buffer of this line.
31 *
32 * Should be called while holding line->lock (this does not modify data).
33 */
34static int write_room(struct line *line)
35{
36 int n;
37
38 if (line->buffer == NULL)
39 return LINE_BUFSIZE - 1;
40
41 /* This is for the case where the buffer is wrapped! */
42 n = line->head - line->tail;
43
44 if (n <= 0)
45 n += LINE_BUFSIZE; /* The other case */
46 return n - 1;
47}
48
49int line_write_room(struct tty_struct *tty)
50{
51 struct line *line = tty->driver_data;
52 unsigned long flags;
53 int room;
54
55 spin_lock_irqsave(&line->lock, flags);
56 room = write_room(line);
57 spin_unlock_irqrestore(&line->lock, flags);
58
59 return room;
60}
61
62int line_chars_in_buffer(struct tty_struct *tty)
63{
64 struct line *line = tty->driver_data;
65 unsigned long flags;
66 int ret;
67
68 spin_lock_irqsave(&line->lock, flags);
69 /* write_room subtracts 1 for the needed NULL, so we readd it.*/
70 ret = LINE_BUFSIZE - (write_room(line) + 1);
71 spin_unlock_irqrestore(&line->lock, flags);
72
73 return ret;
74}
75
76/*
77 * This copies the content of buf into the circular buffer associated with
78 * this line.
79 * The return value is the number of characters actually copied, i.e. the ones
80 * for which there was space: this function is not supposed to ever flush out
81 * the circular buffer.
82 *
83 * Must be called while holding line->lock!
84 */
85static int buffer_data(struct line *line, const char *buf, int len)
86{
87 int end, room;
88
89 if (line->buffer == NULL) {
90 line->buffer = kmalloc(LINE_BUFSIZE, GFP_ATOMIC);
91 if (line->buffer == NULL) {
92 printk(KERN_ERR "buffer_data - atomic allocation "
93 "failed\n");
94 return 0;
95 }
96 line->head = line->buffer;
97 line->tail = line->buffer;
98 }
99
100 room = write_room(line);
101 len = (len > room) ? room : len;
102
103 end = line->buffer + LINE_BUFSIZE - line->tail;
104
105 if (len < end) {
106 memcpy(line->tail, buf, len);
107 line->tail += len;
108 }
109 else {
110 /* The circular buffer is wrapping */
111 memcpy(line->tail, buf, end);
112 buf += end;
113 memcpy(line->buffer, buf, len - end);
114 line->tail = line->buffer + len - end;
115 }
116
117 return len;
118}
119
120/*
121 * Flushes the ring buffer to the output channels. That is, write_chan is
122 * called, passing it line->head as buffer, and an appropriate count.
123 *
124 * On exit, returns 1 when the buffer is empty,
125 * 0 when the buffer is not empty on exit,
126 * and -errno when an error occurred.
127 *
128 * Must be called while holding line->lock!*/
129static int flush_buffer(struct line *line)
130{
131 int n, count;
132
133 if ((line->buffer == NULL) || (line->head == line->tail))
134 return 1;
135
136 if (line->tail < line->head) {
137 /* line->buffer + LINE_BUFSIZE is the end of the buffer! */
138 count = line->buffer + LINE_BUFSIZE - line->head;
139
140 n = write_chan(line->chan_out, line->head, count,
141 line->driver->write_irq);
142 if (n < 0)
143 return n;
144 if (n == count) {
145 /*
146 * We have flushed from ->head to buffer end, now we
147 * must flush only from the beginning to ->tail.
148 */
149 line->head = line->buffer;
150 } else {
151 line->head += n;
152 return 0;
153 }
154 }
155
156 count = line->tail - line->head;
157 n = write_chan(line->chan_out, line->head, count,
158 line->driver->write_irq);
159
160 if (n < 0)
161 return n;
162
163 line->head += n;
164 return line->head == line->tail;
165}
166
167void line_flush_buffer(struct tty_struct *tty)
168{
169 struct line *line = tty->driver_data;
170 unsigned long flags;
171
172 spin_lock_irqsave(&line->lock, flags);
173 flush_buffer(line);
174 spin_unlock_irqrestore(&line->lock, flags);
175}
176
177/*
178 * We map both ->flush_chars and ->put_char (which go in pair) onto
179 * ->flush_buffer and ->write. Hope it's not that bad.
180 */
181void line_flush_chars(struct tty_struct *tty)
182{
183 line_flush_buffer(tty);
184}
185
186int line_put_char(struct tty_struct *tty, unsigned char ch)
187{
188 return line_write(tty, &ch, sizeof(ch));
189}
190
191int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
192{
193 struct line *line = tty->driver_data;
194 unsigned long flags;
195 int n, ret = 0;
196
197 spin_lock_irqsave(&line->lock, flags);
198 if (line->head != line->tail)
199 ret = buffer_data(line, buf, len);
200 else {
201 n = write_chan(line->chan_out, buf, len,
202 line->driver->write_irq);
203 if (n < 0) {
204 ret = n;
205 goto out_up;
206 }
207
208 len -= n;
209 ret += n;
210 if (len > 0)
211 ret += buffer_data(line, buf + n, len);
212 }
213out_up:
214 spin_unlock_irqrestore(&line->lock, flags);
215 return ret;
216}
217
218void line_set_termios(struct tty_struct *tty, struct ktermios * old)
219{
220 /* nothing */
221}
222
223void line_throttle(struct tty_struct *tty)
224{
225 struct line *line = tty->driver_data;
226
227 deactivate_chan(line->chan_in, line->driver->read_irq);
228 line->throttled = 1;
229}
230
231void line_unthrottle(struct tty_struct *tty)
232{
233 struct line *line = tty->driver_data;
234
235 line->throttled = 0;
236 chan_interrupt(line, line->driver->read_irq);
237
238 /*
239 * Maybe there is enough stuff pending that calling the interrupt
240 * throttles us again. In this case, line->throttled will be 1
241 * again and we shouldn't turn the interrupt back on.
242 */
243 if (!line->throttled)
244 reactivate_chan(line->chan_in, line->driver->read_irq);
245}
246
247static irqreturn_t line_write_interrupt(int irq, void *data)
248{
249 struct chan *chan = data;
250 struct line *line = chan->line;
251 int err;
252
253 /*
254 * Interrupts are disabled here because genirq keep irqs disabled when
255 * calling the action handler.
256 */
257
258 spin_lock(&line->lock);
259 err = flush_buffer(line);
260 if (err == 0) {
261 spin_unlock(&line->lock);
262 return IRQ_NONE;
263 } else if (err < 0) {
264 line->head = line->buffer;
265 line->tail = line->buffer;
266 }
267 spin_unlock(&line->lock);
268
269 tty_port_tty_wakeup(&line->port);
270
271 return IRQ_HANDLED;
272}
273
274int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
275{
276 const struct line_driver *driver = line->driver;
277 int err = 0;
278
279 if (input)
280 err = um_request_irq(driver->read_irq, fd, IRQ_READ,
281 line_interrupt, IRQF_SHARED,
282 driver->read_irq_name, data);
283 if (err)
284 return err;
285 if (output)
286 err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
287 line_write_interrupt, IRQF_SHARED,
288 driver->write_irq_name, data);
289 return err;
290}
291
292static int line_activate(struct tty_port *port, struct tty_struct *tty)
293{
294 int ret;
295 struct line *line = tty->driver_data;
296
297 ret = enable_chan(line);
298 if (ret)
299 return ret;
300
301 if (!line->sigio) {
302 chan_enable_winch(line->chan_out, port);
303 line->sigio = 1;
304 }
305
306 chan_window_size(line, &tty->winsize.ws_row,
307 &tty->winsize.ws_col);
308
309 return 0;
310}
311
312static void unregister_winch(struct tty_struct *tty);
313
314static void line_destruct(struct tty_port *port)
315{
316 struct tty_struct *tty = tty_port_tty_get(port);
317 struct line *line = tty->driver_data;
318
319 if (line->sigio) {
320 unregister_winch(tty);
321 line->sigio = 0;
322 }
323}
324
325static const struct tty_port_operations line_port_ops = {
326 .activate = line_activate,
327 .destruct = line_destruct,
328};
329
330int line_open(struct tty_struct *tty, struct file *filp)
331{
332 struct line *line = tty->driver_data;
333
334 return tty_port_open(&line->port, tty, filp);
335}
336
337int line_install(struct tty_driver *driver, struct tty_struct *tty,
338 struct line *line)
339{
340 int ret;
341
342 ret = tty_standard_install(driver, tty);
343 if (ret)
344 return ret;
345
346 tty->driver_data = line;
347
348 return 0;
349}
350
351void line_close(struct tty_struct *tty, struct file * filp)
352{
353 struct line *line = tty->driver_data;
354
355 tty_port_close(&line->port, tty, filp);
356}
357
358void line_hangup(struct tty_struct *tty)
359{
360 struct line *line = tty->driver_data;
361
362 tty_port_hangup(&line->port);
363}
364
365void close_lines(struct line *lines, int nlines)
366{
367 int i;
368
369 for(i = 0; i < nlines; i++)
370 close_chan(&lines[i]);
371}
372
373int setup_one_line(struct line *lines, int n, char *init,
374 const struct chan_opts *opts, char **error_out)
375{
376 struct line *line = &lines[n];
377 struct tty_driver *driver = line->driver->driver;
378 int err = -EINVAL;
379
380 if (line->port.count) {
381 *error_out = "Device is already open";
382 goto out;
383 }
384
385 if (!strcmp(init, "none")) {
386 if (line->valid) {
387 line->valid = 0;
388 kfree(line->init_str);
389 tty_unregister_device(driver, n);
390 parse_chan_pair(NULL, line, n, opts, error_out);
391 err = 0;
392 }
393 } else {
394 char *new = kstrdup(init, GFP_KERNEL);
395 if (!new) {
396 *error_out = "Failed to allocate memory";
397 return -ENOMEM;
398 }
399 if (line->valid) {
400 tty_unregister_device(driver, n);
401 kfree(line->init_str);
402 }
403 line->init_str = new;
404 line->valid = 1;
405 err = parse_chan_pair(new, line, n, opts, error_out);
406 if (!err) {
407 struct device *d = tty_port_register_device(&line->port,
408 driver, n, NULL);
409 if (IS_ERR(d)) {
410 *error_out = "Failed to register device";
411 err = PTR_ERR(d);
412 parse_chan_pair(NULL, line, n, opts, error_out);
413 }
414 }
415 if (err) {
416 line->init_str = NULL;
417 line->valid = 0;
418 kfree(new);
419 }
420 }
421out:
422 return err;
423}
424
425/*
426 * Common setup code for both startup command line and mconsole initialization.
427 * @lines contains the array (of size @num) to modify;
428 * @init is the setup string;
429 * @error_out is an error string in the case of failure;
430 */
431
432int line_setup(char **conf, unsigned int num, char **def,
433 char *init, char *name)
434{
435 char *error;
436
437 if (*init == '=') {
438 /*
439 * We said con=/ssl= instead of con#=, so we are configuring all
440 * consoles at once.
441 */
442 *def = init + 1;
443 } else {
444 char *end;
445 unsigned n = simple_strtoul(init, &end, 0);
446
447 if (*end != '=') {
448 error = "Couldn't parse device number";
449 goto out;
450 }
451 if (n >= num) {
452 error = "Device number out of range";
453 goto out;
454 }
455 conf[n] = end + 1;
456 }
457 return 0;
458
459out:
460 printk(KERN_ERR "Failed to set up %s with "
461 "configuration string \"%s\" : %s\n", name, init, error);
462 return -EINVAL;
463}
464
465int line_config(struct line *lines, unsigned int num, char *str,
466 const struct chan_opts *opts, char **error_out)
467{
468 char *end;
469 int n;
470
471 if (*str == '=') {
472 *error_out = "Can't configure all devices from mconsole";
473 return -EINVAL;
474 }
475
476 n = simple_strtoul(str, &end, 0);
477 if (*end++ != '=') {
478 *error_out = "Couldn't parse device number";
479 return -EINVAL;
480 }
481 if (n >= num) {
482 *error_out = "Device number out of range";
483 return -EINVAL;
484 }
485
486 return setup_one_line(lines, n, end, opts, error_out);
487}
488
489int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
490 int size, char **error_out)
491{
492 struct line *line;
493 char *end;
494 int dev, n = 0;
495
496 dev = simple_strtoul(name, &end, 0);
497 if ((*end != '\0') || (end == name)) {
498 *error_out = "line_get_config failed to parse device number";
499 return 0;
500 }
501
502 if ((dev < 0) || (dev >= num)) {
503 *error_out = "device number out of range";
504 return 0;
505 }
506
507 line = &lines[dev];
508
509 if (!line->valid)
510 CONFIG_CHUNK(str, size, n, "none", 1);
511 else {
512 struct tty_struct *tty = tty_port_tty_get(&line->port);
513 if (tty == NULL) {
514 CONFIG_CHUNK(str, size, n, line->init_str, 1);
515 } else {
516 n = chan_config_string(line, str, size, error_out);
517 tty_kref_put(tty);
518 }
519 }
520
521 return n;
522}
523
524int line_id(char **str, int *start_out, int *end_out)
525{
526 char *end;
527 int n;
528
529 n = simple_strtoul(*str, &end, 0);
530 if ((*end != '\0') || (end == *str))
531 return -1;
532
533 *str = end;
534 *start_out = n;
535 *end_out = n;
536 return n;
537}
538
539int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
540{
541 if (n >= num) {
542 *error_out = "Device number out of range";
543 return -EINVAL;
544 }
545 return setup_one_line(lines, n, "none", NULL, error_out);
546}
547
548int register_lines(struct line_driver *line_driver,
549 const struct tty_operations *ops,
550 struct line *lines, int nlines)
551{
552 struct tty_driver *driver = alloc_tty_driver(nlines);
553 int err;
554 int i;
555
556 if (!driver)
557 return -ENOMEM;
558
559 driver->driver_name = line_driver->name;
560 driver->name = line_driver->device_name;
561 driver->major = line_driver->major;
562 driver->minor_start = line_driver->minor_start;
563 driver->type = line_driver->type;
564 driver->subtype = line_driver->subtype;
565 driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
566 driver->init_termios = tty_std_termios;
567
568 for (i = 0; i < nlines; i++) {
569 tty_port_init(&lines[i].port);
570 lines[i].port.ops = &line_port_ops;
571 spin_lock_init(&lines[i].lock);
572 lines[i].driver = line_driver;
573 INIT_LIST_HEAD(&lines[i].chan_list);
574 }
575 tty_set_operations(driver, ops);
576
577 err = tty_register_driver(driver);
578 if (err) {
579 printk(KERN_ERR "register_lines : can't register %s driver\n",
580 line_driver->name);
581 put_tty_driver(driver);
582 for (i = 0; i < nlines; i++)
583 tty_port_destroy(&lines[i].port);
584 return err;
585 }
586
587 line_driver->driver = driver;
588 mconsole_register_dev(&line_driver->mc);
589 return 0;
590}
591
592static DEFINE_SPINLOCK(winch_handler_lock);
593static LIST_HEAD(winch_handlers);
594
595struct winch {
596 struct list_head list;
597 int fd;
598 int tty_fd;
599 int pid;
600 struct tty_port *port;
601 unsigned long stack;
602 struct work_struct work;
603};
604
605static void __free_winch(struct work_struct *work)
606{
607 struct winch *winch = container_of(work, struct winch, work);
608 um_free_irq(WINCH_IRQ, winch);
609
610 if (winch->pid != -1)
611 os_kill_process(winch->pid, 1);
612 if (winch->stack != 0)
613 free_stack(winch->stack, 0);
614 kfree(winch);
615}
616
617static void free_winch(struct winch *winch)
618{
619 int fd = winch->fd;
620 winch->fd = -1;
621 if (fd != -1)
622 os_close_file(fd);
623 list_del(&winch->list);
624 __free_winch(&winch->work);
625}
626
627static irqreturn_t winch_interrupt(int irq, void *data)
628{
629 struct winch *winch = data;
630 struct tty_struct *tty;
631 struct line *line;
632 int fd = winch->fd;
633 int err;
634 char c;
635 struct pid *pgrp;
636
637 if (fd != -1) {
638 err = generic_read(fd, &c, NULL);
639 if (err < 0) {
640 if (err != -EAGAIN) {
641 winch->fd = -1;
642 list_del(&winch->list);
643 os_close_file(fd);
644 printk(KERN_ERR "winch_interrupt : "
645 "read failed, errno = %d\n", -err);
646 printk(KERN_ERR "fd %d is losing SIGWINCH "
647 "support\n", winch->tty_fd);
648 INIT_WORK(&winch->work, __free_winch);
649 schedule_work(&winch->work);
650 return IRQ_HANDLED;
651 }
652 goto out;
653 }
654 }
655 tty = tty_port_tty_get(winch->port);
656 if (tty != NULL) {
657 line = tty->driver_data;
658 if (line != NULL) {
659 chan_window_size(line, &tty->winsize.ws_row,
660 &tty->winsize.ws_col);
661 pgrp = tty_get_pgrp(tty);
662 if (pgrp)
663 kill_pgrp(pgrp, SIGWINCH, 1);
664 put_pid(pgrp);
665 }
666 tty_kref_put(tty);
667 }
668 out:
669 if (winch->fd != -1)
670 reactivate_fd(winch->fd, WINCH_IRQ);
671 return IRQ_HANDLED;
672}
673
674void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port,
675 unsigned long stack)
676{
677 struct winch *winch;
678
679 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
680 if (winch == NULL) {
681 printk(KERN_ERR "register_winch_irq - kmalloc failed\n");
682 goto cleanup;
683 }
684
685 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
686 .fd = fd,
687 .tty_fd = tty_fd,
688 .pid = pid,
689 .port = port,
690 .stack = stack });
691
692 if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
693 IRQF_SHARED, "winch", winch) < 0) {
694 printk(KERN_ERR "register_winch_irq - failed to register "
695 "IRQ\n");
696 goto out_free;
697 }
698
699 spin_lock(&winch_handler_lock);
700 list_add(&winch->list, &winch_handlers);
701 spin_unlock(&winch_handler_lock);
702
703 return;
704
705 out_free:
706 kfree(winch);
707 cleanup:
708 os_kill_process(pid, 1);
709 os_close_file(fd);
710 if (stack != 0)
711 free_stack(stack, 0);
712}
713
714static void unregister_winch(struct tty_struct *tty)
715{
716 struct list_head *ele, *next;
717 struct winch *winch;
718 struct tty_struct *wtty;
719
720 spin_lock(&winch_handler_lock);
721
722 list_for_each_safe(ele, next, &winch_handlers) {
723 winch = list_entry(ele, struct winch, list);
724 wtty = tty_port_tty_get(winch->port);
725 if (wtty == tty) {
726 free_winch(winch);
727 break;
728 }
729 tty_kref_put(wtty);
730 }
731 spin_unlock(&winch_handler_lock);
732}
733
734static void winch_cleanup(void)
735{
736 struct list_head *ele, *next;
737 struct winch *winch;
738
739 spin_lock(&winch_handler_lock);
740
741 list_for_each_safe(ele, next, &winch_handlers) {
742 winch = list_entry(ele, struct winch, list);
743 free_winch(winch);
744 }
745
746 spin_unlock(&winch_handler_lock);
747}
748__uml_exitcall(winch_cleanup);
749
750char *add_xterm_umid(char *base)
751{
752 char *umid, *title;
753 int len;
754
755 umid = get_umid();
756 if (*umid == '\0')
757 return base;
758
759 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
760 title = kmalloc(len, GFP_KERNEL);
761 if (title == NULL) {
762 printk(KERN_ERR "Failed to allocate buffer for xterm title\n");
763 return base;
764 }
765
766 snprintf(title, len, "%s (%s)", base, umid);
767 return title;
768}