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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/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 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
50int line_write_room(struct tty_struct *tty)
51{
52 struct line *line = tty->driver_data;
53 unsigned long flags;
54 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
63int line_chars_in_buffer(struct tty_struct *tty)
64{
65 struct line *line = tty->driver_data;
66 unsigned long flags;
67 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->driver->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->driver->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_put_char(struct tty_struct *tty, unsigned char ch)
188{
189 return line_write(tty, &ch, sizeof(ch));
190}
191
192int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
193{
194 struct line *line = tty->driver_data;
195 unsigned long flags;
196 int n, ret = 0;
197
198 spin_lock_irqsave(&line->lock, flags);
199 if (line->head != line->tail)
200 ret = buffer_data(line, buf, len);
201 else {
202 n = write_chan(line->chan_out, buf, len,
203 line->driver->write_irq);
204 if (n < 0) {
205 ret = n;
206 goto out_up;
207 }
208
209 len -= n;
210 ret += n;
211 if (len > 0)
212 ret += buffer_data(line, buf + n, len);
213 }
214out_up:
215 spin_unlock_irqrestore(&line->lock, flags);
216 return ret;
217}
218
219void line_set_termios(struct tty_struct *tty, struct ktermios * old)
220{
221 /* nothing */
222}
223
224void line_throttle(struct tty_struct *tty)
225{
226 struct line *line = tty->driver_data;
227
228 deactivate_chan(line->chan_in, line->driver->read_irq);
229 line->throttled = 1;
230}
231
232void line_unthrottle(struct tty_struct *tty)
233{
234 struct line *line = tty->driver_data;
235
236 line->throttled = 0;
237 chan_interrupt(line, line->driver->read_irq);
238
239 /*
240 * Maybe there is enough stuff pending that calling the interrupt
241 * throttles us again. In this case, line->throttled will be 1
242 * again and we shouldn't turn the interrupt back on.
243 */
244 if (!line->throttled)
245 reactivate_chan(line->chan_in, line->driver->read_irq);
246}
247
248static irqreturn_t line_write_interrupt(int irq, void *data)
249{
250 struct chan *chan = data;
251 struct line *line = chan->line;
252 int err;
253
254 /*
255 * Interrupts are disabled here because genirq keep irqs disabled when
256 * calling the action handler.
257 */
258
259 spin_lock(&line->lock);
260 err = flush_buffer(line);
261 if (err == 0) {
262 spin_unlock(&line->lock);
263 return IRQ_NONE;
264 } else if (err < 0) {
265 line->head = line->buffer;
266 line->tail = line->buffer;
267 }
268 spin_unlock(&line->lock);
269
270 tty_port_tty_wakeup(&line->port);
271
272 return IRQ_HANDLED;
273}
274
275int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
276{
277 const struct line_driver *driver = line->driver;
278 int err = 0;
279
280 if (input)
281 err = um_request_irq(driver->read_irq, fd, IRQ_READ,
282 line_interrupt, IRQF_SHARED,
283 driver->read_irq_name, data);
284 if (err)
285 return err;
286 if (output)
287 err = um_request_irq(driver->write_irq, fd, IRQ_NONE,
288 line_write_interrupt, IRQF_SHARED,
289 driver->write_irq_name, data);
290 return err;
291}
292
293static int line_activate(struct tty_port *port, struct tty_struct *tty)
294{
295 int ret;
296 struct line *line = tty->driver_data;
297
298 ret = enable_chan(line);
299 if (ret)
300 return ret;
301
302 if (!line->sigio) {
303 chan_enable_winch(line->chan_out, port);
304 line->sigio = 1;
305 }
306
307 chan_window_size(line, &tty->winsize.ws_row,
308 &tty->winsize.ws_col);
309
310 return 0;
311}
312
313static void unregister_winch(struct tty_struct *tty);
314
315static void line_destruct(struct tty_port *port)
316{
317 struct tty_struct *tty = tty_port_tty_get(port);
318 struct line *line = tty->driver_data;
319
320 if (line->sigio) {
321 unregister_winch(tty);
322 line->sigio = 0;
323 }
324}
325
326static const struct tty_port_operations line_port_ops = {
327 .activate = line_activate,
328 .destruct = line_destruct,
329};
330
331int line_open(struct tty_struct *tty, struct file *filp)
332{
333 struct line *line = tty->driver_data;
334
335 return tty_port_open(&line->port, tty, filp);
336}
337
338int line_install(struct tty_driver *driver, struct tty_struct *tty,
339 struct line *line)
340{
341 int ret;
342
343 ret = tty_standard_install(driver, tty);
344 if (ret)
345 return ret;
346
347 tty->driver_data = line;
348
349 return 0;
350}
351
352void line_close(struct tty_struct *tty, struct file * filp)
353{
354 struct line *line = tty->driver_data;
355
356 tty_port_close(&line->port, tty, filp);
357}
358
359void line_hangup(struct tty_struct *tty)
360{
361 struct line *line = tty->driver_data;
362
363 tty_port_hangup(&line->port);
364}
365
366void close_lines(struct line *lines, int nlines)
367{
368 int i;
369
370 for(i = 0; i < nlines; i++)
371 close_chan(&lines[i]);
372}
373
374int setup_one_line(struct line *lines, int n, char *init,
375 const struct chan_opts *opts, char **error_out)
376{
377 struct line *line = &lines[n];
378 struct tty_driver *driver = line->driver->driver;
379 int err = -EINVAL;
380
381 if (line->port.count) {
382 *error_out = "Device is already open";
383 goto out;
384 }
385
386 if (!strcmp(init, "none")) {
387 if (line->valid) {
388 line->valid = 0;
389 kfree(line->init_str);
390 tty_unregister_device(driver, n);
391 parse_chan_pair(NULL, line, n, opts, error_out);
392 err = 0;
393 }
394 } else {
395 char *new = kstrdup(init, GFP_KERNEL);
396 if (!new) {
397 *error_out = "Failed to allocate memory";
398 return -ENOMEM;
399 }
400 if (line->valid) {
401 tty_unregister_device(driver, n);
402 kfree(line->init_str);
403 }
404 line->init_str = new;
405 line->valid = 1;
406 err = parse_chan_pair(new, line, n, opts, error_out);
407 if (!err) {
408 struct device *d = tty_port_register_device(&line->port,
409 driver, n, NULL);
410 if (IS_ERR(d)) {
411 *error_out = "Failed to register device";
412 err = PTR_ERR(d);
413 parse_chan_pair(NULL, line, n, opts, error_out);
414 }
415 }
416 if (err) {
417 line->init_str = NULL;
418 line->valid = 0;
419 kfree(new);
420 }
421 }
422out:
423 return err;
424}
425
426/*
427 * Common setup code for both startup command line and mconsole initialization.
428 * @lines contains the array (of size @num) to modify;
429 * @init is the setup string;
430 * @error_out is an error string in the case of failure;
431 */
432
433int line_setup(char **conf, unsigned int num, char **def,
434 char *init, char *name)
435{
436 char *error;
437
438 if (*init == '=') {
439 /*
440 * We said con=/ssl= instead of con#=, so we are configuring all
441 * consoles at once.
442 */
443 *def = init + 1;
444 } else {
445 char *end;
446 unsigned n = simple_strtoul(init, &end, 0);
447
448 if (*end != '=') {
449 error = "Couldn't parse device number";
450 goto out;
451 }
452 if (n >= num) {
453 error = "Device number out of range";
454 goto out;
455 }
456 conf[n] = end + 1;
457 }
458 return 0;
459
460out:
461 printk(KERN_ERR "Failed to set up %s with "
462 "configuration string \"%s\" : %s\n", name, init, error);
463 return -EINVAL;
464}
465
466int line_config(struct line *lines, unsigned int num, char *str,
467 const struct chan_opts *opts, char **error_out)
468{
469 char *end;
470 int n;
471
472 if (*str == '=') {
473 *error_out = "Can't configure all devices from mconsole";
474 return -EINVAL;
475 }
476
477 n = simple_strtoul(str, &end, 0);
478 if (*end++ != '=') {
479 *error_out = "Couldn't parse device number";
480 return -EINVAL;
481 }
482 if (n >= num) {
483 *error_out = "Device number out of range";
484 return -EINVAL;
485 }
486
487 return setup_one_line(lines, n, end, opts, error_out);
488}
489
490int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
491 int size, char **error_out)
492{
493 struct line *line;
494 char *end;
495 int dev, n = 0;
496
497 dev = simple_strtoul(name, &end, 0);
498 if ((*end != '\0') || (end == name)) {
499 *error_out = "line_get_config failed to parse device number";
500 return 0;
501 }
502
503 if ((dev < 0) || (dev >= num)) {
504 *error_out = "device number out of range";
505 return 0;
506 }
507
508 line = &lines[dev];
509
510 if (!line->valid)
511 CONFIG_CHUNK(str, size, n, "none", 1);
512 else {
513 struct tty_struct *tty = tty_port_tty_get(&line->port);
514 if (tty == NULL) {
515 CONFIG_CHUNK(str, size, n, line->init_str, 1);
516 } else {
517 n = chan_config_string(line, str, size, error_out);
518 tty_kref_put(tty);
519 }
520 }
521
522 return n;
523}
524
525int line_id(char **str, int *start_out, int *end_out)
526{
527 char *end;
528 int n;
529
530 n = simple_strtoul(*str, &end, 0);
531 if ((*end != '\0') || (end == *str))
532 return -1;
533
534 *str = end;
535 *start_out = n;
536 *end_out = n;
537 return n;
538}
539
540int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
541{
542 if (n >= num) {
543 *error_out = "Device number out of range";
544 return -EINVAL;
545 }
546 return setup_one_line(lines, n, "none", NULL, error_out);
547}
548
549int register_lines(struct line_driver *line_driver,
550 const struct tty_operations *ops,
551 struct line *lines, int nlines)
552{
553 struct tty_driver *driver = alloc_tty_driver(nlines);
554 int err;
555 int i;
556
557 if (!driver)
558 return -ENOMEM;
559
560 driver->driver_name = line_driver->name;
561 driver->name = line_driver->device_name;
562 driver->major = line_driver->major;
563 driver->minor_start = line_driver->minor_start;
564 driver->type = line_driver->type;
565 driver->subtype = line_driver->subtype;
566 driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
567 driver->init_termios = tty_std_termios;
568
569 for (i = 0; i < nlines; i++) {
570 tty_port_init(&lines[i].port);
571 lines[i].port.ops = &line_port_ops;
572 spin_lock_init(&lines[i].lock);
573 lines[i].driver = line_driver;
574 INIT_LIST_HEAD(&lines[i].chan_list);
575 }
576 tty_set_operations(driver, ops);
577
578 err = tty_register_driver(driver);
579 if (err) {
580 printk(KERN_ERR "register_lines : can't register %s driver\n",
581 line_driver->name);
582 put_tty_driver(driver);
583 for (i = 0; i < nlines; i++)
584 tty_port_destroy(&lines[i].port);
585 return err;
586 }
587
588 line_driver->driver = driver;
589 mconsole_register_dev(&line_driver->mc);
590 return 0;
591}
592
593static DEFINE_SPINLOCK(winch_handler_lock);
594static LIST_HEAD(winch_handlers);
595
596struct winch {
597 struct list_head list;
598 int fd;
599 int tty_fd;
600 int pid;
601 struct tty_port *port;
602 unsigned long stack;
603 struct work_struct work;
604};
605
606static void __free_winch(struct work_struct *work)
607{
608 struct winch *winch = container_of(work, struct winch, work);
609 um_free_irq(WINCH_IRQ, winch);
610
611 if (winch->pid != -1)
612 os_kill_process(winch->pid, 1);
613 if (winch->stack != 0)
614 free_stack(winch->stack, 0);
615 kfree(winch);
616}
617
618static void free_winch(struct winch *winch)
619{
620 int fd = winch->fd;
621 winch->fd = -1;
622 if (fd != -1)
623 os_close_file(fd);
624 list_del(&winch->list);
625 __free_winch(&winch->work);
626}
627
628static irqreturn_t winch_interrupt(int irq, void *data)
629{
630 struct winch *winch = data;
631 struct tty_struct *tty;
632 struct line *line;
633 int fd = winch->fd;
634 int err;
635 char c;
636 struct pid *pgrp;
637
638 if (fd != -1) {
639 err = generic_read(fd, &c, NULL);
640 if (err < 0) {
641 if (err != -EAGAIN) {
642 winch->fd = -1;
643 list_del(&winch->list);
644 os_close_file(fd);
645 printk(KERN_ERR "winch_interrupt : "
646 "read failed, errno = %d\n", -err);
647 printk(KERN_ERR "fd %d is losing SIGWINCH "
648 "support\n", winch->tty_fd);
649 INIT_WORK(&winch->work, __free_winch);
650 schedule_work(&winch->work);
651 return IRQ_HANDLED;
652 }
653 goto out;
654 }
655 }
656 tty = tty_port_tty_get(winch->port);
657 if (tty != NULL) {
658 line = tty->driver_data;
659 if (line != NULL) {
660 chan_window_size(line, &tty->winsize.ws_row,
661 &tty->winsize.ws_col);
662 pgrp = tty_get_pgrp(tty);
663 if (pgrp)
664 kill_pgrp(pgrp, SIGWINCH, 1);
665 put_pid(pgrp);
666 }
667 tty_kref_put(tty);
668 }
669 out:
670 if (winch->fd != -1)
671 reactivate_fd(winch->fd, WINCH_IRQ);
672 return IRQ_HANDLED;
673}
674
675void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port,
676 unsigned long stack)
677{
678 struct winch *winch;
679
680 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
681 if (winch == NULL) {
682 printk(KERN_ERR "register_winch_irq - kmalloc failed\n");
683 goto cleanup;
684 }
685
686 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
687 .fd = fd,
688 .tty_fd = tty_fd,
689 .pid = pid,
690 .port = port,
691 .stack = stack });
692
693 if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
694 IRQF_SHARED, "winch", winch) < 0) {
695 printk(KERN_ERR "register_winch_irq - failed to register "
696 "IRQ\n");
697 goto out_free;
698 }
699
700 spin_lock(&winch_handler_lock);
701 list_add(&winch->list, &winch_handlers);
702 spin_unlock(&winch_handler_lock);
703
704 return;
705
706 out_free:
707 kfree(winch);
708 cleanup:
709 os_kill_process(pid, 1);
710 os_close_file(fd);
711 if (stack != 0)
712 free_stack(stack, 0);
713}
714
715static void unregister_winch(struct tty_struct *tty)
716{
717 struct list_head *ele, *next;
718 struct winch *winch;
719 struct tty_struct *wtty;
720
721 spin_lock(&winch_handler_lock);
722
723 list_for_each_safe(ele, next, &winch_handlers) {
724 winch = list_entry(ele, struct winch, list);
725 wtty = tty_port_tty_get(winch->port);
726 if (wtty == tty) {
727 free_winch(winch);
728 break;
729 }
730 tty_kref_put(wtty);
731 }
732 spin_unlock(&winch_handler_lock);
733}
734
735static void winch_cleanup(void)
736{
737 struct list_head *ele, *next;
738 struct winch *winch;
739
740 spin_lock(&winch_handler_lock);
741
742 list_for_each_safe(ele, next, &winch_handlers) {
743 winch = list_entry(ele, struct winch, list);
744 free_winch(winch);
745 }
746
747 spin_unlock(&winch_handler_lock);
748}
749__uml_exitcall(winch_cleanup);
750
751char *add_xterm_umid(char *base)
752{
753 char *umid, *title;
754 int len;
755
756 umid = get_umid();
757 if (*umid == '\0')
758 return base;
759
760 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
761 title = kmalloc(len, GFP_KERNEL);
762 if (title == NULL) {
763 printk(KERN_ERR "Failed to allocate buffer for xterm title\n");
764 return base;
765 }
766
767 snprintf(title, len, "%s (%s)", base, umid);
768 return title;
769}