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 | |
19 | static 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 | */ |
35 | static 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 | |
50 | unsigned 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(lock: &line->lock, flags); |
59 | |
60 | return room; |
61 | } |
62 | |
63 | unsigned 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(lock: &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 | */ |
86 | static int buffer_data(struct line *line, const u8 *buf, size_t 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!*/ |
130 | static 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(chan: line->chan_out, buf: line->head, len: count, |
142 | write_irq: 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(chan: line->chan_out, buf: line->head, len: count, |
159 | write_irq: line->write_irq); |
160 | |
161 | if (n < 0) |
162 | return n; |
163 | |
164 | line->head += n; |
165 | return line->head == line->tail; |
166 | } |
167 | |
168 | void 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(lock: &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 | */ |
182 | void line_flush_chars(struct tty_struct *tty) |
183 | { |
184 | line_flush_buffer(tty); |
185 | } |
186 | |
187 | ssize_t line_write(struct tty_struct *tty, const u8 *buf, size_t 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(chan: line->chan_out, buf, len, |
198 | write_irq: 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: buf + n, len); |
208 | } |
209 | out_up: |
210 | spin_unlock_irqrestore(lock: &line->lock, flags); |
211 | return ret; |
212 | } |
213 | |
214 | void line_throttle(struct tty_struct *tty) |
215 | { |
216 | struct line *line = tty->driver_data; |
217 | |
218 | deactivate_chan(chan: line->chan_in, irq: line->read_irq); |
219 | line->throttled = 1; |
220 | } |
221 | |
222 | void line_unthrottle(struct tty_struct *tty) |
223 | { |
224 | struct line *line = tty->driver_data; |
225 | |
226 | line->throttled = 0; |
227 | chan_interrupt(line, irq: line->read_irq); |
228 | } |
229 | |
230 | static 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(lock: &line->lock); |
242 | err = flush_buffer(line); |
243 | if (err == 0) { |
244 | spin_unlock(lock: &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(lock: &line->lock); |
251 | |
252 | tty_port_tty_wakeup(port: &line->port); |
253 | |
254 | return IRQ_HANDLED; |
255 | } |
256 | |
257 | int 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 | |
285 | static 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(chan: line->chan_out, port); |
296 | line->sigio = 1; |
297 | } |
298 | |
299 | chan_window_size(line, rows_out: &tty->winsize.ws_row, |
300 | cols_out: &tty->winsize.ws_col); |
301 | |
302 | return 0; |
303 | } |
304 | |
305 | static void unregister_winch(struct tty_struct *tty); |
306 | |
307 | static 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 | |
318 | static const struct tty_port_operations line_port_ops = { |
319 | .activate = line_activate, |
320 | .destruct = line_destruct, |
321 | }; |
322 | |
323 | int line_open(struct tty_struct *tty, struct file *filp) |
324 | { |
325 | struct line *line = tty->driver_data; |
326 | |
327 | return tty_port_open(port: &line->port, tty, filp); |
328 | } |
329 | |
330 | int 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 | |
344 | void line_close(struct tty_struct *tty, struct file * filp) |
345 | { |
346 | struct line *line = tty->driver_data; |
347 | |
348 | tty_port_close(port: &line->port, tty, filp); |
349 | } |
350 | |
351 | void line_hangup(struct tty_struct *tty) |
352 | { |
353 | struct line *line = tty->driver_data; |
354 | |
355 | tty_port_hangup(port: &line->port); |
356 | } |
357 | |
358 | void close_lines(struct line *lines, int nlines) |
359 | { |
360 | int i; |
361 | |
362 | for(i = 0; i < nlines; i++) |
363 | close_chan(line: &lines[i]); |
364 | } |
365 | |
366 | int 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(objp: line->init_str); |
382 | tty_unregister_device(driver, index: n); |
383 | parse_chan_pair(NULL, line, device: n, opts, error_out); |
384 | err = 0; |
385 | } |
386 | } else { |
387 | char *new = kstrdup(s: 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, index: n); |
394 | kfree(objp: line->init_str); |
395 | } |
396 | line->init_str = new; |
397 | line->valid = 1; |
398 | err = parse_chan_pair(str: new, line, device: n, opts, error_out); |
399 | if (!err) { |
400 | struct device *d = tty_port_register_device(port: &line->port, |
401 | driver, index: n, NULL); |
402 | if (IS_ERR(ptr: d)) { |
403 | *error_out = "Failed to register device" ; |
404 | err = PTR_ERR(ptr: d); |
405 | parse_chan_pair(NULL, line, device: n, opts, error_out); |
406 | } |
407 | } |
408 | if (err) { |
409 | line->init_str = NULL; |
410 | line->valid = 0; |
411 | kfree(objp: new); |
412 | } |
413 | } |
414 | out: |
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 | |
425 | int 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 | |
452 | out: |
453 | printk(KERN_ERR "Failed to set up %s with " |
454 | "configuration string \"%s\" : %s\n" , name, init, error); |
455 | return -EINVAL; |
456 | } |
457 | |
458 | int 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, init: end, opts, error_out); |
480 | } |
481 | |
482 | int 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(port: &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 | |
517 | int 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 | |
532 | int 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, init: "none" , NULL, error_out); |
539 | } |
540 | |
541 | int 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(ptr: driver)) |
552 | return PTR_ERR(ptr: 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(port: &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(list: &lines[i].chan_list); |
568 | } |
569 | tty_set_operations(driver, op: 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(port: &lines[i].port); |
578 | return err; |
579 | } |
580 | |
581 | line_driver->driver = driver; |
582 | mconsole_register_dev(new: &line_driver->mc); |
583 | return 0; |
584 | } |
585 | |
586 | static DEFINE_SPINLOCK(winch_handler_lock); |
587 | static LIST_HEAD(winch_handlers); |
588 | |
589 | struct 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 | |
599 | static 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(objp: winch); |
609 | } |
610 | |
611 | static 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(work: &winch->work); |
618 | } |
619 | |
620 | static 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_out: &c, NULL); |
632 | /* A read of 2 means the winch thread failed and has warned */ |
633 | if (err < 0 || (err == 1 && c == 2)) { |
634 | if (err != -EAGAIN) { |
635 | winch->fd = -1; |
636 | list_del(entry: &winch->list); |
637 | os_close_file(fd); |
638 | if (err < 0) { |
639 | printk(KERN_ERR "winch_interrupt : read failed, errno = %d\n" , |
640 | -err); |
641 | printk(KERN_ERR "fd %d is losing SIGWINCH support\n" , |
642 | winch->tty_fd); |
643 | } |
644 | INIT_WORK(&winch->work, __free_winch); |
645 | schedule_work(work: &winch->work); |
646 | return IRQ_HANDLED; |
647 | } |
648 | goto out; |
649 | } |
650 | } |
651 | tty = tty_port_tty_get(port: winch->port); |
652 | if (tty != NULL) { |
653 | line = tty->driver_data; |
654 | if (line != NULL) { |
655 | chan_window_size(line, rows_out: &tty->winsize.ws_row, |
656 | cols_out: &tty->winsize.ws_col); |
657 | pgrp = tty_get_pgrp(tty); |
658 | if (pgrp) |
659 | kill_pgrp(pid: pgrp, SIGWINCH, priv: 1); |
660 | put_pid(pid: pgrp); |
661 | } |
662 | tty_kref_put(tty); |
663 | } |
664 | out: |
665 | return IRQ_HANDLED; |
666 | } |
667 | |
668 | void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port, |
669 | unsigned long stack) |
670 | { |
671 | struct winch *winch; |
672 | |
673 | winch = kmalloc(size: sizeof(*winch), GFP_KERNEL); |
674 | if (winch == NULL) { |
675 | printk(KERN_ERR "register_winch_irq - kmalloc failed\n" ); |
676 | goto cleanup; |
677 | } |
678 | |
679 | *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list), |
680 | .fd = fd, |
681 | .tty_fd = tty_fd, |
682 | .pid = pid, |
683 | .port = port, |
684 | .stack = stack }); |
685 | |
686 | if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt, |
687 | IRQF_SHARED, "winch" , winch) < 0) { |
688 | printk(KERN_ERR "register_winch_irq - failed to register " |
689 | "IRQ\n" ); |
690 | goto out_free; |
691 | } |
692 | |
693 | spin_lock(lock: &winch_handler_lock); |
694 | list_add(new: &winch->list, head: &winch_handlers); |
695 | spin_unlock(lock: &winch_handler_lock); |
696 | |
697 | return; |
698 | |
699 | out_free: |
700 | kfree(objp: winch); |
701 | cleanup: |
702 | os_kill_process(pid, 1); |
703 | os_close_file(fd); |
704 | if (stack != 0) |
705 | free_stack(stack, 0); |
706 | } |
707 | |
708 | static void unregister_winch(struct tty_struct *tty) |
709 | { |
710 | struct list_head *ele, *next; |
711 | struct winch *winch; |
712 | struct tty_struct *wtty; |
713 | |
714 | spin_lock(lock: &winch_handler_lock); |
715 | |
716 | list_for_each_safe(ele, next, &winch_handlers) { |
717 | winch = list_entry(ele, struct winch, list); |
718 | wtty = tty_port_tty_get(port: winch->port); |
719 | if (wtty == tty) { |
720 | list_del(entry: &winch->list); |
721 | spin_unlock(lock: &winch_handler_lock); |
722 | free_winch(winch); |
723 | break; |
724 | } |
725 | tty_kref_put(tty: wtty); |
726 | } |
727 | spin_unlock(lock: &winch_handler_lock); |
728 | } |
729 | |
730 | static void winch_cleanup(void) |
731 | { |
732 | struct winch *winch; |
733 | |
734 | spin_lock(lock: &winch_handler_lock); |
735 | while ((winch = list_first_entry_or_null(&winch_handlers, |
736 | struct winch, list))) { |
737 | list_del(entry: &winch->list); |
738 | spin_unlock(lock: &winch_handler_lock); |
739 | |
740 | free_winch(winch); |
741 | |
742 | spin_lock(lock: &winch_handler_lock); |
743 | } |
744 | |
745 | spin_unlock(lock: &winch_handler_lock); |
746 | } |
747 | __uml_exitcall(winch_cleanup); |
748 | |
749 | char *add_xterm_umid(char *base) |
750 | { |
751 | char *umid, *title; |
752 | int len; |
753 | |
754 | umid = get_umid(); |
755 | if (*umid == '\0') |
756 | return base; |
757 | |
758 | len = strlen(base) + strlen(" ()" ) + strlen(umid) + 1; |
759 | title = kmalloc(size: len, GFP_KERNEL); |
760 | if (title == NULL) { |
761 | printk(KERN_ERR "Failed to allocate buffer for xterm title\n" ); |
762 | return base; |
763 | } |
764 | |
765 | snprintf(buf: title, size: len, fmt: "%s (%s)" , base, umid); |
766 | return title; |
767 | } |
768 | |