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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
4 */
5
6#include <linux/slab.h>
7#include <linux/tty.h>
8#include <linux/tty_flip.h>
9#include "chan.h"
10#include <os.h>
11#include <irq_kern.h>
12
13#ifdef CONFIG_NOCONFIG_CHAN
14static void *not_configged_init(char *str, int device,
15 const struct chan_opts *opts)
16{
17 printk(KERN_ERR "Using a channel type which is configured out of "
18 "UML\n");
19 return NULL;
20}
21
22static int not_configged_open(int input, int output, int primary, void *data,
23 char **dev_out)
24{
25 printk(KERN_ERR "Using a channel type which is configured out of "
26 "UML\n");
27 return -ENODEV;
28}
29
30static void not_configged_close(int fd, void *data)
31{
32 printk(KERN_ERR "Using a channel type which is configured out of "
33 "UML\n");
34}
35
36static int not_configged_read(int fd, char *c_out, void *data)
37{
38 printk(KERN_ERR "Using a channel type which is configured out of "
39 "UML\n");
40 return -EIO;
41}
42
43static int not_configged_write(int fd, const char *buf, int len, void *data)
44{
45 printk(KERN_ERR "Using a channel type which is configured out of "
46 "UML\n");
47 return -EIO;
48}
49
50static int not_configged_console_write(int fd, const char *buf, int len)
51{
52 printk(KERN_ERR "Using a channel type which is configured out of "
53 "UML\n");
54 return -EIO;
55}
56
57static int not_configged_window_size(int fd, void *data, unsigned short *rows,
58 unsigned short *cols)
59{
60 printk(KERN_ERR "Using a channel type which is configured out of "
61 "UML\n");
62 return -ENODEV;
63}
64
65static void not_configged_free(void *data)
66{
67 printk(KERN_ERR "Using a channel type which is configured out of "
68 "UML\n");
69}
70
71static const struct chan_ops not_configged_ops = {
72 .init = not_configged_init,
73 .open = not_configged_open,
74 .close = not_configged_close,
75 .read = not_configged_read,
76 .write = not_configged_write,
77 .console_write = not_configged_console_write,
78 .window_size = not_configged_window_size,
79 .free = not_configged_free,
80 .winch = 0,
81};
82#endif /* CONFIG_NOCONFIG_CHAN */
83
84static int open_one_chan(struct chan *chan)
85{
86 int fd, err;
87
88 if (chan->opened)
89 return 0;
90
91 if (chan->ops->open == NULL)
92 fd = 0;
93 else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary,
94 chan->data, &chan->dev);
95 if (fd < 0)
96 return fd;
97
98 err = os_set_fd_block(fd, 0);
99 if (err) {
100 (*chan->ops->close)(fd, chan->data);
101 return err;
102 }
103
104 chan->fd = fd;
105
106 chan->opened = 1;
107 return 0;
108}
109
110static int open_chan(struct list_head *chans)
111{
112 struct list_head *ele;
113 struct chan *chan;
114 int ret, err = 0;
115
116 list_for_each(ele, chans) {
117 chan = list_entry(ele, struct chan, list);
118 ret = open_one_chan(chan);
119 if (chan->primary)
120 err = ret;
121 }
122 return err;
123}
124
125void chan_enable_winch(struct chan *chan, struct tty_port *port)
126{
127 if (chan && chan->primary && chan->ops->winch)
128 register_winch(chan->fd, port);
129}
130
131static void line_timer_cb(struct work_struct *work)
132{
133 struct line *line = container_of(work, struct line, task.work);
134
135 if (!line->throttled)
136 chan_interrupt(line, line->read_irq);
137}
138
139int enable_chan(struct line *line)
140{
141 struct list_head *ele;
142 struct chan *chan;
143 int err;
144
145 INIT_DELAYED_WORK(&line->task, line_timer_cb);
146
147 list_for_each(ele, &line->chan_list) {
148 chan = list_entry(ele, struct chan, list);
149 err = open_one_chan(chan);
150 if (err) {
151 if (chan->primary)
152 goto out_close;
153
154 continue;
155 }
156
157 if (chan->enabled)
158 continue;
159 err = line_setup_irq(chan->fd, chan->input, chan->output, line,
160 chan);
161 if (err)
162 goto out_close;
163
164 chan->enabled = 1;
165 }
166
167 return 0;
168
169 out_close:
170 close_chan(line);
171 return err;
172}
173
174/* Items are added in IRQ context, when free_irq can't be called, and
175 * removed in process context, when it can.
176 * This handles interrupt sources which disappear, and which need to
177 * be permanently disabled. This is discovered in IRQ context, but
178 * the freeing of the IRQ must be done later.
179 */
180static DEFINE_SPINLOCK(irqs_to_free_lock);
181static LIST_HEAD(irqs_to_free);
182
183void free_irqs(void)
184{
185 struct chan *chan;
186 LIST_HEAD(list);
187 struct list_head *ele;
188 unsigned long flags;
189
190 spin_lock_irqsave(&irqs_to_free_lock, flags);
191 list_splice_init(&irqs_to_free, &list);
192 spin_unlock_irqrestore(&irqs_to_free_lock, flags);
193
194 list_for_each(ele, &list) {
195 chan = list_entry(ele, struct chan, free_list);
196
197 if (chan->input && chan->enabled)
198 um_free_irq(chan->line->read_irq, chan);
199 if (chan->output && chan->enabled)
200 um_free_irq(chan->line->write_irq, chan);
201 chan->enabled = 0;
202 }
203}
204
205static void close_one_chan(struct chan *chan, int delay_free_irq)
206{
207 unsigned long flags;
208
209 if (!chan->opened)
210 return;
211
212 if (delay_free_irq) {
213 spin_lock_irqsave(&irqs_to_free_lock, flags);
214 list_add(&chan->free_list, &irqs_to_free);
215 spin_unlock_irqrestore(&irqs_to_free_lock, flags);
216 } else {
217 if (chan->input && chan->enabled)
218 um_free_irq(chan->line->read_irq, chan);
219 if (chan->output && chan->enabled)
220 um_free_irq(chan->line->write_irq, chan);
221 chan->enabled = 0;
222 }
223 if (chan->ops->close != NULL)
224 (*chan->ops->close)(chan->fd, chan->data);
225
226 chan->opened = 0;
227 chan->fd = -1;
228}
229
230void close_chan(struct line *line)
231{
232 struct chan *chan;
233
234 /* Close in reverse order as open in case more than one of them
235 * refers to the same device and they save and restore that device's
236 * state. Then, the first one opened will have the original state,
237 * so it must be the last closed.
238 */
239 list_for_each_entry_reverse(chan, &line->chan_list, list) {
240 close_one_chan(chan, 0);
241 }
242}
243
244void deactivate_chan(struct chan *chan, int irq)
245{
246 if (chan && chan->enabled)
247 deactivate_fd(chan->fd, irq);
248}
249
250int write_chan(struct chan *chan, const char *buf, int len,
251 int write_irq)
252{
253 int n, ret = 0;
254
255 if (len == 0 || !chan || !chan->ops->write)
256 return 0;
257
258 n = chan->ops->write(chan->fd, buf, len, chan->data);
259 if (chan->primary) {
260 ret = n;
261 }
262 return ret;
263}
264
265int console_write_chan(struct chan *chan, const char *buf, int len)
266{
267 int n, ret = 0;
268
269 if (!chan || !chan->ops->console_write)
270 return 0;
271
272 n = chan->ops->console_write(chan->fd, buf, len);
273 if (chan->primary)
274 ret = n;
275 return ret;
276}
277
278int console_open_chan(struct line *line, struct console *co)
279{
280 int err;
281
282 err = open_chan(&line->chan_list);
283 if (err)
284 return err;
285
286 printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name,
287 co->index);
288 return 0;
289}
290
291int chan_window_size(struct line *line, unsigned short *rows_out,
292 unsigned short *cols_out)
293{
294 struct chan *chan;
295
296 chan = line->chan_in;
297 if (chan && chan->primary) {
298 if (chan->ops->window_size == NULL)
299 return 0;
300 return chan->ops->window_size(chan->fd, chan->data,
301 rows_out, cols_out);
302 }
303 chan = line->chan_out;
304 if (chan && chan->primary) {
305 if (chan->ops->window_size == NULL)
306 return 0;
307 return chan->ops->window_size(chan->fd, chan->data,
308 rows_out, cols_out);
309 }
310 return 0;
311}
312
313static void free_one_chan(struct chan *chan)
314{
315 list_del(&chan->list);
316
317 close_one_chan(chan, 0);
318
319 if (chan->ops->free != NULL)
320 (*chan->ops->free)(chan->data);
321
322 if (chan->primary && chan->output)
323 ignore_sigio_fd(chan->fd);
324 kfree(chan);
325}
326
327static void free_chan(struct list_head *chans)
328{
329 struct list_head *ele, *next;
330 struct chan *chan;
331
332 list_for_each_safe(ele, next, chans) {
333 chan = list_entry(ele, struct chan, list);
334 free_one_chan(chan);
335 }
336}
337
338static int one_chan_config_string(struct chan *chan, char *str, int size,
339 char **error_out)
340{
341 int n = 0;
342
343 if (chan == NULL) {
344 CONFIG_CHUNK(str, size, n, "none", 1);
345 return n;
346 }
347
348 CONFIG_CHUNK(str, size, n, chan->ops->type, 0);
349
350 if (chan->dev == NULL) {
351 CONFIG_CHUNK(str, size, n, "", 1);
352 return n;
353 }
354
355 CONFIG_CHUNK(str, size, n, ":", 0);
356 CONFIG_CHUNK(str, size, n, chan->dev, 0);
357
358 return n;
359}
360
361static int chan_pair_config_string(struct chan *in, struct chan *out,
362 char *str, int size, char **error_out)
363{
364 int n;
365
366 n = one_chan_config_string(in, str, size, error_out);
367 str += n;
368 size -= n;
369
370 if (in == out) {
371 CONFIG_CHUNK(str, size, n, "", 1);
372 return n;
373 }
374
375 CONFIG_CHUNK(str, size, n, ",", 1);
376 n = one_chan_config_string(out, str, size, error_out);
377 str += n;
378 size -= n;
379 CONFIG_CHUNK(str, size, n, "", 1);
380
381 return n;
382}
383
384int chan_config_string(struct line *line, char *str, int size,
385 char **error_out)
386{
387 struct chan *in = line->chan_in, *out = line->chan_out;
388
389 if (in && !in->primary)
390 in = NULL;
391 if (out && !out->primary)
392 out = NULL;
393
394 return chan_pair_config_string(in, out, str, size, error_out);
395}
396
397struct chan_type {
398 char *key;
399 const struct chan_ops *ops;
400};
401
402static const struct chan_type chan_table[] = {
403 { "fd", &fd_ops },
404
405#ifdef CONFIG_NULL_CHAN
406 { "null", &null_ops },
407#else
408 { "null", ¬_configged_ops },
409#endif
410
411#ifdef CONFIG_PORT_CHAN
412 { "port", &port_ops },
413#else
414 { "port", ¬_configged_ops },
415#endif
416
417#ifdef CONFIG_PTY_CHAN
418 { "pty", &pty_ops },
419 { "pts", &pts_ops },
420#else
421 { "pty", ¬_configged_ops },
422 { "pts", ¬_configged_ops },
423#endif
424
425#ifdef CONFIG_TTY_CHAN
426 { "tty", &tty_ops },
427#else
428 { "tty", ¬_configged_ops },
429#endif
430
431#ifdef CONFIG_XTERM_CHAN
432 { "xterm", &xterm_ops },
433#else
434 { "xterm", ¬_configged_ops },
435#endif
436};
437
438static struct chan *parse_chan(struct line *line, char *str, int device,
439 const struct chan_opts *opts, char **error_out)
440{
441 const struct chan_type *entry;
442 const struct chan_ops *ops;
443 struct chan *chan;
444 void *data;
445 int i;
446
447 ops = NULL;
448 data = NULL;
449 for(i = 0; i < ARRAY_SIZE(chan_table); i++) {
450 entry = &chan_table[i];
451 if (!strncmp(str, entry->key, strlen(entry->key))) {
452 ops = entry->ops;
453 str += strlen(entry->key);
454 break;
455 }
456 }
457 if (ops == NULL) {
458 *error_out = "No match for configured backends";
459 return NULL;
460 }
461
462 data = (*ops->init)(str, device, opts);
463 if (data == NULL) {
464 *error_out = "Configuration failed";
465 return NULL;
466 }
467
468 chan = kmalloc(sizeof(*chan), GFP_ATOMIC);
469 if (chan == NULL) {
470 *error_out = "Memory allocation failed";
471 return NULL;
472 }
473 *chan = ((struct chan) { .list = LIST_HEAD_INIT(chan->list),
474 .free_list =
475 LIST_HEAD_INIT(chan->free_list),
476 .line = line,
477 .primary = 1,
478 .input = 0,
479 .output = 0,
480 .opened = 0,
481 .enabled = 0,
482 .fd = -1,
483 .ops = ops,
484 .data = data });
485 return chan;
486}
487
488int parse_chan_pair(char *str, struct line *line, int device,
489 const struct chan_opts *opts, char **error_out)
490{
491 struct list_head *chans = &line->chan_list;
492 struct chan *new;
493 char *in, *out;
494
495 if (!list_empty(chans)) {
496 line->chan_in = line->chan_out = NULL;
497 free_chan(chans);
498 INIT_LIST_HEAD(chans);
499 }
500
501 if (!str)
502 return 0;
503
504 out = strchr(str, ',');
505 if (out != NULL) {
506 in = str;
507 *out = '\0';
508 out++;
509 new = parse_chan(line, in, device, opts, error_out);
510 if (new == NULL)
511 return -1;
512
513 new->input = 1;
514 list_add(&new->list, chans);
515 line->chan_in = new;
516
517 new = parse_chan(line, out, device, opts, error_out);
518 if (new == NULL)
519 return -1;
520
521 list_add(&new->list, chans);
522 new->output = 1;
523 line->chan_out = new;
524 }
525 else {
526 new = parse_chan(line, str, device, opts, error_out);
527 if (new == NULL)
528 return -1;
529
530 list_add(&new->list, chans);
531 new->input = 1;
532 new->output = 1;
533 line->chan_in = line->chan_out = new;
534 }
535 return 0;
536}
537
538void chan_interrupt(struct line *line, int irq)
539{
540 struct tty_port *port = &line->port;
541 struct chan *chan = line->chan_in;
542 int err;
543 char c;
544
545 if (!chan || !chan->ops->read)
546 goto out;
547
548 do {
549 if (!tty_buffer_request_room(port, 1)) {
550 schedule_delayed_work(&line->task, 1);
551 goto out;
552 }
553 err = chan->ops->read(chan->fd, &c, chan->data);
554 if (err > 0)
555 tty_insert_flip_char(port, c, TTY_NORMAL);
556 } while (err > 0);
557
558 if (err == -EIO) {
559 if (chan->primary) {
560 tty_port_tty_hangup(&line->port, false);
561 if (line->chan_out != chan)
562 close_one_chan(line->chan_out, 1);
563 }
564 close_one_chan(chan, 1);
565 if (chan->primary)
566 return;
567 }
568 out:
569 tty_flip_buffer_push(port);
570}
1/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/slab.h>
7#include <linux/tty.h>
8#include <linux/tty_flip.h>
9#include "chan_kern.h"
10#include "os.h"
11
12#ifdef CONFIG_NOCONFIG_CHAN
13static void *not_configged_init(char *str, int device,
14 const struct chan_opts *opts)
15{
16 printk(KERN_ERR "Using a channel type which is configured out of "
17 "UML\n");
18 return NULL;
19}
20
21static int not_configged_open(int input, int output, int primary, void *data,
22 char **dev_out)
23{
24 printk(KERN_ERR "Using a channel type which is configured out of "
25 "UML\n");
26 return -ENODEV;
27}
28
29static void not_configged_close(int fd, void *data)
30{
31 printk(KERN_ERR "Using a channel type which is configured out of "
32 "UML\n");
33}
34
35static int not_configged_read(int fd, char *c_out, void *data)
36{
37 printk(KERN_ERR "Using a channel type which is configured out of "
38 "UML\n");
39 return -EIO;
40}
41
42static int not_configged_write(int fd, const char *buf, int len, void *data)
43{
44 printk(KERN_ERR "Using a channel type which is configured out of "
45 "UML\n");
46 return -EIO;
47}
48
49static int not_configged_console_write(int fd, const char *buf, int len)
50{
51 printk(KERN_ERR "Using a channel type which is configured out of "
52 "UML\n");
53 return -EIO;
54}
55
56static int not_configged_window_size(int fd, void *data, unsigned short *rows,
57 unsigned short *cols)
58{
59 printk(KERN_ERR "Using a channel type which is configured out of "
60 "UML\n");
61 return -ENODEV;
62}
63
64static void not_configged_free(void *data)
65{
66 printk(KERN_ERR "Using a channel type which is configured out of "
67 "UML\n");
68}
69
70static const struct chan_ops not_configged_ops = {
71 .init = not_configged_init,
72 .open = not_configged_open,
73 .close = not_configged_close,
74 .read = not_configged_read,
75 .write = not_configged_write,
76 .console_write = not_configged_console_write,
77 .window_size = not_configged_window_size,
78 .free = not_configged_free,
79 .winch = 0,
80};
81#endif /* CONFIG_NOCONFIG_CHAN */
82
83static void tty_receive_char(struct tty_struct *tty, char ch)
84{
85 if (tty == NULL)
86 return;
87
88 if (I_IXON(tty) && !I_IXOFF(tty) && !tty->raw) {
89 if (ch == STOP_CHAR(tty)) {
90 stop_tty(tty);
91 return;
92 }
93 else if (ch == START_CHAR(tty)) {
94 start_tty(tty);
95 return;
96 }
97 }
98
99 tty_insert_flip_char(tty, ch, TTY_NORMAL);
100}
101
102static int open_one_chan(struct chan *chan)
103{
104 int fd, err;
105
106 if (chan->opened)
107 return 0;
108
109 if (chan->ops->open == NULL)
110 fd = 0;
111 else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary,
112 chan->data, &chan->dev);
113 if (fd < 0)
114 return fd;
115
116 err = os_set_fd_block(fd, 0);
117 if (err) {
118 (*chan->ops->close)(fd, chan->data);
119 return err;
120 }
121
122 chan->fd = fd;
123
124 chan->opened = 1;
125 return 0;
126}
127
128static int open_chan(struct list_head *chans)
129{
130 struct list_head *ele;
131 struct chan *chan;
132 int ret, err = 0;
133
134 list_for_each(ele, chans) {
135 chan = list_entry(ele, struct chan, list);
136 ret = open_one_chan(chan);
137 if (chan->primary)
138 err = ret;
139 }
140 return err;
141}
142
143void chan_enable_winch(struct list_head *chans, struct tty_struct *tty)
144{
145 struct list_head *ele;
146 struct chan *chan;
147
148 list_for_each(ele, chans) {
149 chan = list_entry(ele, struct chan, list);
150 if (chan->primary && chan->output && chan->ops->winch) {
151 register_winch(chan->fd, tty);
152 return;
153 }
154 }
155}
156
157int enable_chan(struct line *line)
158{
159 struct list_head *ele;
160 struct chan *chan;
161 int err;
162
163 list_for_each(ele, &line->chan_list) {
164 chan = list_entry(ele, struct chan, list);
165 err = open_one_chan(chan);
166 if (err) {
167 if (chan->primary)
168 goto out_close;
169
170 continue;
171 }
172
173 if (chan->enabled)
174 continue;
175 err = line_setup_irq(chan->fd, chan->input, chan->output, line,
176 chan);
177 if (err)
178 goto out_close;
179
180 chan->enabled = 1;
181 }
182
183 return 0;
184
185 out_close:
186 close_chan(&line->chan_list, 0);
187 return err;
188}
189
190/* Items are added in IRQ context, when free_irq can't be called, and
191 * removed in process context, when it can.
192 * This handles interrupt sources which disappear, and which need to
193 * be permanently disabled. This is discovered in IRQ context, but
194 * the freeing of the IRQ must be done later.
195 */
196static DEFINE_SPINLOCK(irqs_to_free_lock);
197static LIST_HEAD(irqs_to_free);
198
199void free_irqs(void)
200{
201 struct chan *chan;
202 LIST_HEAD(list);
203 struct list_head *ele;
204 unsigned long flags;
205
206 spin_lock_irqsave(&irqs_to_free_lock, flags);
207 list_splice_init(&irqs_to_free, &list);
208 spin_unlock_irqrestore(&irqs_to_free_lock, flags);
209
210 list_for_each(ele, &list) {
211 chan = list_entry(ele, struct chan, free_list);
212
213 if (chan->input && chan->enabled)
214 free_irq(chan->line->driver->read_irq, chan);
215 if (chan->output && chan->enabled)
216 free_irq(chan->line->driver->write_irq, chan);
217 chan->enabled = 0;
218 }
219}
220
221static void close_one_chan(struct chan *chan, int delay_free_irq)
222{
223 unsigned long flags;
224
225 if (!chan->opened)
226 return;
227
228 if (delay_free_irq) {
229 spin_lock_irqsave(&irqs_to_free_lock, flags);
230 list_add(&chan->free_list, &irqs_to_free);
231 spin_unlock_irqrestore(&irqs_to_free_lock, flags);
232 }
233 else {
234 if (chan->input && chan->enabled)
235 free_irq(chan->line->driver->read_irq, chan);
236 if (chan->output && chan->enabled)
237 free_irq(chan->line->driver->write_irq, chan);
238 chan->enabled = 0;
239 }
240 if (chan->ops->close != NULL)
241 (*chan->ops->close)(chan->fd, chan->data);
242
243 chan->opened = 0;
244 chan->fd = -1;
245}
246
247void close_chan(struct list_head *chans, int delay_free_irq)
248{
249 struct chan *chan;
250
251 /* Close in reverse order as open in case more than one of them
252 * refers to the same device and they save and restore that device's
253 * state. Then, the first one opened will have the original state,
254 * so it must be the last closed.
255 */
256 list_for_each_entry_reverse(chan, chans, list) {
257 close_one_chan(chan, delay_free_irq);
258 }
259}
260
261void deactivate_chan(struct list_head *chans, int irq)
262{
263 struct list_head *ele;
264
265 struct chan *chan;
266 list_for_each(ele, chans) {
267 chan = list_entry(ele, struct chan, list);
268
269 if (chan->enabled && chan->input)
270 deactivate_fd(chan->fd, irq);
271 }
272}
273
274void reactivate_chan(struct list_head *chans, int irq)
275{
276 struct list_head *ele;
277 struct chan *chan;
278
279 list_for_each(ele, chans) {
280 chan = list_entry(ele, struct chan, list);
281
282 if (chan->enabled && chan->input)
283 reactivate_fd(chan->fd, irq);
284 }
285}
286
287int write_chan(struct list_head *chans, const char *buf, int len,
288 int write_irq)
289{
290 struct list_head *ele;
291 struct chan *chan = NULL;
292 int n, ret = 0;
293
294 if (len == 0)
295 return 0;
296
297 list_for_each(ele, chans) {
298 chan = list_entry(ele, struct chan, list);
299 if (!chan->output || (chan->ops->write == NULL))
300 continue;
301
302 n = chan->ops->write(chan->fd, buf, len, chan->data);
303 if (chan->primary) {
304 ret = n;
305 if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
306 reactivate_fd(chan->fd, write_irq);
307 }
308 }
309 return ret;
310}
311
312int console_write_chan(struct list_head *chans, const char *buf, int len)
313{
314 struct list_head *ele;
315 struct chan *chan;
316 int n, ret = 0;
317
318 list_for_each(ele, chans) {
319 chan = list_entry(ele, struct chan, list);
320 if (!chan->output || (chan->ops->console_write == NULL))
321 continue;
322
323 n = chan->ops->console_write(chan->fd, buf, len);
324 if (chan->primary)
325 ret = n;
326 }
327 return ret;
328}
329
330int console_open_chan(struct line *line, struct console *co)
331{
332 int err;
333
334 err = open_chan(&line->chan_list);
335 if (err)
336 return err;
337
338 printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name,
339 co->index);
340 return 0;
341}
342
343int chan_window_size(struct list_head *chans, unsigned short *rows_out,
344 unsigned short *cols_out)
345{
346 struct list_head *ele;
347 struct chan *chan;
348
349 list_for_each(ele, chans) {
350 chan = list_entry(ele, struct chan, list);
351 if (chan->primary) {
352 if (chan->ops->window_size == NULL)
353 return 0;
354 return chan->ops->window_size(chan->fd, chan->data,
355 rows_out, cols_out);
356 }
357 }
358 return 0;
359}
360
361static void free_one_chan(struct chan *chan, int delay_free_irq)
362{
363 list_del(&chan->list);
364
365 close_one_chan(chan, delay_free_irq);
366
367 if (chan->ops->free != NULL)
368 (*chan->ops->free)(chan->data);
369
370 if (chan->primary && chan->output)
371 ignore_sigio_fd(chan->fd);
372 kfree(chan);
373}
374
375static void free_chan(struct list_head *chans, int delay_free_irq)
376{
377 struct list_head *ele, *next;
378 struct chan *chan;
379
380 list_for_each_safe(ele, next, chans) {
381 chan = list_entry(ele, struct chan, list);
382 free_one_chan(chan, delay_free_irq);
383 }
384}
385
386static int one_chan_config_string(struct chan *chan, char *str, int size,
387 char **error_out)
388{
389 int n = 0;
390
391 if (chan == NULL) {
392 CONFIG_CHUNK(str, size, n, "none", 1);
393 return n;
394 }
395
396 CONFIG_CHUNK(str, size, n, chan->ops->type, 0);
397
398 if (chan->dev == NULL) {
399 CONFIG_CHUNK(str, size, n, "", 1);
400 return n;
401 }
402
403 CONFIG_CHUNK(str, size, n, ":", 0);
404 CONFIG_CHUNK(str, size, n, chan->dev, 0);
405
406 return n;
407}
408
409static int chan_pair_config_string(struct chan *in, struct chan *out,
410 char *str, int size, char **error_out)
411{
412 int n;
413
414 n = one_chan_config_string(in, str, size, error_out);
415 str += n;
416 size -= n;
417
418 if (in == out) {
419 CONFIG_CHUNK(str, size, n, "", 1);
420 return n;
421 }
422
423 CONFIG_CHUNK(str, size, n, ",", 1);
424 n = one_chan_config_string(out, str, size, error_out);
425 str += n;
426 size -= n;
427 CONFIG_CHUNK(str, size, n, "", 1);
428
429 return n;
430}
431
432int chan_config_string(struct list_head *chans, char *str, int size,
433 char **error_out)
434{
435 struct list_head *ele;
436 struct chan *chan, *in = NULL, *out = NULL;
437
438 list_for_each(ele, chans) {
439 chan = list_entry(ele, struct chan, list);
440 if (!chan->primary)
441 continue;
442 if (chan->input)
443 in = chan;
444 if (chan->output)
445 out = chan;
446 }
447
448 return chan_pair_config_string(in, out, str, size, error_out);
449}
450
451struct chan_type {
452 char *key;
453 const struct chan_ops *ops;
454};
455
456static const struct chan_type chan_table[] = {
457 { "fd", &fd_ops },
458
459#ifdef CONFIG_NULL_CHAN
460 { "null", &null_ops },
461#else
462 { "null", ¬_configged_ops },
463#endif
464
465#ifdef CONFIG_PORT_CHAN
466 { "port", &port_ops },
467#else
468 { "port", ¬_configged_ops },
469#endif
470
471#ifdef CONFIG_PTY_CHAN
472 { "pty", &pty_ops },
473 { "pts", &pts_ops },
474#else
475 { "pty", ¬_configged_ops },
476 { "pts", ¬_configged_ops },
477#endif
478
479#ifdef CONFIG_TTY_CHAN
480 { "tty", &tty_ops },
481#else
482 { "tty", ¬_configged_ops },
483#endif
484
485#ifdef CONFIG_XTERM_CHAN
486 { "xterm", &xterm_ops },
487#else
488 { "xterm", ¬_configged_ops },
489#endif
490};
491
492static struct chan *parse_chan(struct line *line, char *str, int device,
493 const struct chan_opts *opts, char **error_out)
494{
495 const struct chan_type *entry;
496 const struct chan_ops *ops;
497 struct chan *chan;
498 void *data;
499 int i;
500
501 ops = NULL;
502 data = NULL;
503 for(i = 0; i < ARRAY_SIZE(chan_table); i++) {
504 entry = &chan_table[i];
505 if (!strncmp(str, entry->key, strlen(entry->key))) {
506 ops = entry->ops;
507 str += strlen(entry->key);
508 break;
509 }
510 }
511 if (ops == NULL) {
512 *error_out = "No match for configured backends";
513 return NULL;
514 }
515
516 data = (*ops->init)(str, device, opts);
517 if (data == NULL) {
518 *error_out = "Configuration failed";
519 return NULL;
520 }
521
522 chan = kmalloc(sizeof(*chan), GFP_ATOMIC);
523 if (chan == NULL) {
524 *error_out = "Memory allocation failed";
525 return NULL;
526 }
527 *chan = ((struct chan) { .list = LIST_HEAD_INIT(chan->list),
528 .free_list =
529 LIST_HEAD_INIT(chan->free_list),
530 .line = line,
531 .primary = 1,
532 .input = 0,
533 .output = 0,
534 .opened = 0,
535 .enabled = 0,
536 .fd = -1,
537 .ops = ops,
538 .data = data });
539 return chan;
540}
541
542int parse_chan_pair(char *str, struct line *line, int device,
543 const struct chan_opts *opts, char **error_out)
544{
545 struct list_head *chans = &line->chan_list;
546 struct chan *new;
547 char *in, *out;
548
549 if (!list_empty(chans)) {
550 free_chan(chans, 0);
551 INIT_LIST_HEAD(chans);
552 }
553
554 out = strchr(str, ',');
555 if (out != NULL) {
556 in = str;
557 *out = '\0';
558 out++;
559 new = parse_chan(line, in, device, opts, error_out);
560 if (new == NULL)
561 return -1;
562
563 new->input = 1;
564 list_add(&new->list, chans);
565
566 new = parse_chan(line, out, device, opts, error_out);
567 if (new == NULL)
568 return -1;
569
570 list_add(&new->list, chans);
571 new->output = 1;
572 }
573 else {
574 new = parse_chan(line, str, device, opts, error_out);
575 if (new == NULL)
576 return -1;
577
578 list_add(&new->list, chans);
579 new->input = 1;
580 new->output = 1;
581 }
582 return 0;
583}
584
585void chan_interrupt(struct list_head *chans, struct delayed_work *task,
586 struct tty_struct *tty, int irq)
587{
588 struct list_head *ele, *next;
589 struct chan *chan;
590 int err;
591 char c;
592
593 list_for_each_safe(ele, next, chans) {
594 chan = list_entry(ele, struct chan, list);
595 if (!chan->input || (chan->ops->read == NULL))
596 continue;
597 do {
598 if (tty && !tty_buffer_request_room(tty, 1)) {
599 schedule_delayed_work(task, 1);
600 goto out;
601 }
602 err = chan->ops->read(chan->fd, &c, chan->data);
603 if (err > 0)
604 tty_receive_char(tty, c);
605 } while (err > 0);
606
607 if (err == 0)
608 reactivate_fd(chan->fd, irq);
609 if (err == -EIO) {
610 if (chan->primary) {
611 if (tty != NULL)
612 tty_hangup(tty);
613 close_chan(chans, 1);
614 return;
615 }
616 else close_one_chan(chan, 1);
617 }
618 }
619 out:
620 if (tty)
621 tty_flip_buffer_push(tty);
622}