2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
6 #include <linux/irqreturn.h>
8 #include <linux/sched.h>
9 #include <linux/slab.h>
13 #include <kern_util.h>
16 #define LINE_BUFSIZE 4096
18 static irqreturn_t line_interrupt(int irq, void *data)
20 struct chan *chan = data;
21 struct line *line = chan->line;
22 struct tty_struct *tty = tty_port_tty_get(&line->port);
25 chan_interrupt(line, tty, irq);
31 * Returns the free space inside the ring buffer of this line.
33 * Should be called while holding line->lock (this does not modify data).
35 static int write_room(struct line *line)
39 if (line->buffer == NULL)
40 return LINE_BUFSIZE - 1;
42 /* This is for the case where the buffer is wrapped! */
43 n = line->head - line->tail;
46 n += LINE_BUFSIZE; /* The other case */
50 int line_write_room(struct tty_struct *tty)
52 struct line *line = tty->driver_data;
56 spin_lock_irqsave(&line->lock, flags);
57 room = write_room(line);
58 spin_unlock_irqrestore(&line->lock, flags);
63 int line_chars_in_buffer(struct tty_struct *tty)
65 struct line *line = tty->driver_data;
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);
78 * This copies the content of buf into the circular buffer associated with
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.
84 * Must be called while holding line->lock!
86 static int buffer_data(struct line *line, const char *buf, int len)
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 "
97 line->head = line->buffer;
98 line->tail = line->buffer;
101 room = write_room(line);
102 len = (len > room) ? room : len;
104 end = line->buffer + LINE_BUFSIZE - line->tail;
107 memcpy(line->tail, buf, len);
111 /* The circular buffer is wrapping */
112 memcpy(line->tail, buf, end);
114 memcpy(line->buffer, buf, len - end);
115 line->tail = line->buffer + len - end;
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.
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.
129 * Must be called while holding line->lock!*/
130 static int flush_buffer(struct line *line)
134 if ((line->buffer == NULL) || (line->head == line->tail))
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;
141 n = write_chan(line->chan_out, line->head, count,
142 line->driver->write_irq);
147 * We have flushed from ->head to buffer end, now we
148 * must flush only from the beginning to ->tail.
150 line->head = line->buffer;
157 count = line->tail - line->head;
158 n = write_chan(line->chan_out, line->head, count,
159 line->driver->write_irq);
165 return line->head == line->tail;
168 void line_flush_buffer(struct tty_struct *tty)
170 struct line *line = tty->driver_data;
173 spin_lock_irqsave(&line->lock, flags);
175 spin_unlock_irqrestore(&line->lock, flags);
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.
182 void line_flush_chars(struct tty_struct *tty)
184 line_flush_buffer(tty);
187 int line_put_char(struct tty_struct *tty, unsigned char ch)
189 return line_write(tty, &ch, sizeof(ch));
192 int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
194 struct line *line = tty->driver_data;
198 spin_lock_irqsave(&line->lock, flags);
199 if (line->head != line->tail)
200 ret = buffer_data(line, buf, len);
202 n = write_chan(line->chan_out, buf, len,
203 line->driver->write_irq);
212 ret += buffer_data(line, buf + n, len);
215 spin_unlock_irqrestore(&line->lock, flags);
219 void line_set_termios(struct tty_struct *tty, struct ktermios * old)
224 void line_throttle(struct tty_struct *tty)
226 struct line *line = tty->driver_data;
228 deactivate_chan(line->chan_in, line->driver->read_irq);
232 void line_unthrottle(struct tty_struct *tty)
234 struct line *line = tty->driver_data;
237 chan_interrupt(line, tty, line->driver->read_irq);
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.
244 if (!line->throttled)
245 reactivate_chan(line->chan_in, line->driver->read_irq);
248 static irqreturn_t line_write_interrupt(int irq, void *data)
250 struct chan *chan = data;
251 struct line *line = chan->line;
252 struct tty_struct *tty;
256 * Interrupts are disabled here because genirq keep irqs disabled when
257 * calling the action handler.
260 spin_lock(&line->lock);
261 err = flush_buffer(line);
263 spin_unlock(&line->lock);
265 } else if (err < 0) {
266 line->head = line->buffer;
267 line->tail = line->buffer;
269 spin_unlock(&line->lock);
271 tty = tty_port_tty_get(&line->port);
281 int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
283 const struct line_driver *driver = line->driver;
287 err = um_request_irq(driver->read_irq, fd, IRQ_READ,
288 line_interrupt, IRQF_SHARED,
289 driver->read_irq_name, data);
293 err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
294 line_write_interrupt, IRQF_SHARED,
295 driver->write_irq_name, data);
299 static int line_activate(struct tty_port *port, struct tty_struct *tty)
302 struct line *line = tty->driver_data;
304 ret = enable_chan(line);
309 chan_enable_winch(line->chan_out, tty);
313 chan_window_size(line, &tty->winsize.ws_row,
314 &tty->winsize.ws_col);
319 static const struct tty_port_operations line_port_ops = {
320 .activate = line_activate,
323 int line_open(struct tty_struct *tty, struct file *filp)
325 struct line *line = tty->driver_data;
327 return tty_port_open(&line->port, tty, filp);
330 int line_install(struct tty_driver *driver, struct tty_struct *tty,
335 ret = tty_standard_install(driver, tty);
339 tty->driver_data = line;
344 static void unregister_winch(struct tty_struct *tty);
346 void line_cleanup(struct tty_struct *tty)
348 struct line *line = tty->driver_data;
351 unregister_winch(tty);
356 void line_close(struct tty_struct *tty, struct file * filp)
358 struct line *line = tty->driver_data;
360 tty_port_close(&line->port, tty, filp);
363 void line_hangup(struct tty_struct *tty)
365 struct line *line = tty->driver_data;
367 tty_port_hangup(&line->port);
370 void close_lines(struct line *lines, int nlines)
374 for(i = 0; i < nlines; i++)
375 close_chan(&lines[i]);
378 int setup_one_line(struct line *lines, int n, char *init,
379 const struct chan_opts *opts, char **error_out)
381 struct line *line = &lines[n];
382 struct tty_driver *driver = line->driver->driver;
385 if (line->port.count) {
386 *error_out = "Device is already open";
390 if (!strcmp(init, "none")) {
393 kfree(line->init_str);
394 tty_unregister_device(driver, n);
395 parse_chan_pair(NULL, line, n, opts, error_out);
399 char *new = kstrdup(init, GFP_KERNEL);
401 *error_out = "Failed to allocate memory";
405 tty_unregister_device(driver, n);
406 kfree(line->init_str);
408 line->init_str = new;
410 err = parse_chan_pair(new, line, n, opts, error_out);
412 struct device *d = tty_register_device(driver, n, NULL);
414 *error_out = "Failed to register device";
416 parse_chan_pair(NULL, line, n, opts, error_out);
420 line->init_str = NULL;
430 * Common setup code for both startup command line and mconsole initialization.
431 * @lines contains the array (of size @num) to modify;
432 * @init is the setup string;
433 * @error_out is an error string in the case of failure;
436 int line_setup(char **conf, unsigned int num, char **def,
437 char *init, char *name)
443 * We said con=/ssl= instead of con#=, so we are configuring all
449 unsigned n = simple_strtoul(init, &end, 0);
452 error = "Couldn't parse device number";
456 error = "Device number out of range";
464 printk(KERN_ERR "Failed to set up %s with "
465 "configuration string \"%s\" : %s\n", name, init, error);
469 int line_config(struct line *lines, unsigned int num, char *str,
470 const struct chan_opts *opts, char **error_out)
476 *error_out = "Can't configure all devices from mconsole";
480 n = simple_strtoul(str, &end, 0);
482 *error_out = "Couldn't parse device number";
486 *error_out = "Device number out of range";
490 return setup_one_line(lines, n, end, opts, error_out);
493 int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
494 int size, char **error_out)
500 dev = simple_strtoul(name, &end, 0);
501 if ((*end != '\0') || (end == name)) {
502 *error_out = "line_get_config failed to parse device number";
506 if ((dev < 0) || (dev >= num)) {
507 *error_out = "device number out of range";
514 CONFIG_CHUNK(str, size, n, "none", 1);
516 struct tty_struct *tty = tty_port_tty_get(&line->port);
518 CONFIG_CHUNK(str, size, n, line->init_str, 1);
520 n = chan_config_string(line, str, size, error_out);
528 int line_id(char **str, int *start_out, int *end_out)
533 n = simple_strtoul(*str, &end, 0);
534 if ((*end != '\0') || (end == *str))
543 int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
546 *error_out = "Device number out of range";
549 return setup_one_line(lines, n, "none", NULL, error_out);
552 int register_lines(struct line_driver *line_driver,
553 const struct tty_operations *ops,
554 struct line *lines, int nlines)
556 struct tty_driver *driver = alloc_tty_driver(nlines);
563 driver->driver_name = line_driver->name;
564 driver->name = line_driver->device_name;
565 driver->major = line_driver->major;
566 driver->minor_start = line_driver->minor_start;
567 driver->type = line_driver->type;
568 driver->subtype = line_driver->subtype;
569 driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
570 driver->init_termios = tty_std_termios;
572 for (i = 0; i < nlines; i++) {
573 tty_port_init(&lines[i].port);
574 lines[i].port.ops = &line_port_ops;
575 spin_lock_init(&lines[i].lock);
576 lines[i].driver = line_driver;
577 INIT_LIST_HEAD(&lines[i].chan_list);
579 tty_set_operations(driver, ops);
581 err = tty_register_driver(driver);
583 printk(KERN_ERR "register_lines : can't register %s driver\n",
585 put_tty_driver(driver);
589 line_driver->driver = driver;
590 mconsole_register_dev(&line_driver->mc);
594 static DEFINE_SPINLOCK(winch_handler_lock);
595 static LIST_HEAD(winch_handlers);
598 struct list_head list;
602 struct tty_struct *tty;
604 struct work_struct work;
607 static void __free_winch(struct work_struct *work)
609 struct winch *winch = container_of(work, struct winch, work);
610 um_free_irq(WINCH_IRQ, winch);
612 if (winch->pid != -1)
613 os_kill_process(winch->pid, 1);
614 if (winch->stack != 0)
615 free_stack(winch->stack, 0);
619 static void free_winch(struct winch *winch)
625 list_del(&winch->list);
626 __free_winch(&winch->work);
629 static irqreturn_t winch_interrupt(int irq, void *data)
631 struct winch *winch = data;
632 struct tty_struct *tty;
639 err = generic_read(fd, &c, NULL);
641 if (err != -EAGAIN) {
643 list_del(&winch->list);
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);
658 line = tty->driver_data;
660 chan_window_size(line, &tty->winsize.ws_row,
661 &tty->winsize.ws_col);
662 kill_pgrp(tty->pgrp, SIGWINCH, 1);
667 reactivate_fd(winch->fd, WINCH_IRQ);
671 void register_winch_irq(int fd, int tty_fd, int pid, struct tty_struct *tty,
676 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
678 printk(KERN_ERR "register_winch_irq - kmalloc failed\n");
682 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
689 if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
690 IRQF_SHARED, "winch", winch) < 0) {
691 printk(KERN_ERR "register_winch_irq - failed to register "
696 spin_lock(&winch_handler_lock);
697 list_add(&winch->list, &winch_handlers);
698 spin_unlock(&winch_handler_lock);
705 os_kill_process(pid, 1);
708 free_stack(stack, 0);
711 static void unregister_winch(struct tty_struct *tty)
713 struct list_head *ele, *next;
716 spin_lock(&winch_handler_lock);
718 list_for_each_safe(ele, next, &winch_handlers) {
719 winch = list_entry(ele, struct winch, list);
720 if (winch->tty == tty) {
725 spin_unlock(&winch_handler_lock);
728 static void winch_cleanup(void)
730 struct list_head *ele, *next;
733 spin_lock(&winch_handler_lock);
735 list_for_each_safe(ele, next, &winch_handlers) {
736 winch = list_entry(ele, struct winch, list);
740 spin_unlock(&winch_handler_lock);
742 __uml_exitcall(winch_cleanup);
744 char *add_xterm_umid(char *base)
753 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
754 title = kmalloc(len, GFP_KERNEL);
756 printk(KERN_ERR "Failed to allocate buffer for xterm title\n");
760 snprintf(title, len, "%s (%s)", base, umid);