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;
24 chan_interrupt(line, irq);
30 * Returns the free space inside the ring buffer of this line.
32 * Should be called while holding line->lock (this does not modify data).
34 static int write_room(struct line *line)
38 if (line->buffer == NULL)
39 return LINE_BUFSIZE - 1;
41 /* This is for the case where the buffer is wrapped! */
42 n = line->head - line->tail;
45 n += LINE_BUFSIZE; /* The other case */
49 int line_write_room(struct tty_struct *tty)
51 struct line *line = tty->driver_data;
55 spin_lock_irqsave(&line->lock, flags);
56 room = write_room(line);
57 spin_unlock_irqrestore(&line->lock, flags);
62 int line_chars_in_buffer(struct tty_struct *tty)
64 struct line *line = tty->driver_data;
68 spin_lock_irqsave(&line->lock, flags);
69 /* write_room subtracts 1 for the needed NULL, so we readd it.*/
70 ret = LINE_BUFSIZE - (write_room(line) + 1);
71 spin_unlock_irqrestore(&line->lock, flags);
77 * This copies the content of buf into the circular buffer associated with
79 * The return value is the number of characters actually copied, i.e. the ones
80 * for which there was space: this function is not supposed to ever flush out
81 * the circular buffer.
83 * Must be called while holding line->lock!
85 static int buffer_data(struct line *line, const char *buf, int len)
89 if (line->buffer == NULL) {
90 line->buffer = kmalloc(LINE_BUFSIZE, GFP_ATOMIC);
91 if (line->buffer == NULL) {
92 printk(KERN_ERR "buffer_data - atomic allocation "
96 line->head = line->buffer;
97 line->tail = line->buffer;
100 room = write_room(line);
101 len = (len > room) ? room : len;
103 end = line->buffer + LINE_BUFSIZE - line->tail;
106 memcpy(line->tail, buf, len);
110 /* The circular buffer is wrapping */
111 memcpy(line->tail, buf, end);
113 memcpy(line->buffer, buf, len - end);
114 line->tail = line->buffer + len - end;
121 * Flushes the ring buffer to the output channels. That is, write_chan is
122 * called, passing it line->head as buffer, and an appropriate count.
124 * On exit, returns 1 when the buffer is empty,
125 * 0 when the buffer is not empty on exit,
126 * and -errno when an error occurred.
128 * Must be called while holding line->lock!*/
129 static int flush_buffer(struct line *line)
133 if ((line->buffer == NULL) || (line->head == line->tail))
136 if (line->tail < line->head) {
137 /* line->buffer + LINE_BUFSIZE is the end of the buffer! */
138 count = line->buffer + LINE_BUFSIZE - line->head;
140 n = write_chan(line->chan_out, line->head, count,
141 line->driver->write_irq);
146 * We have flushed from ->head to buffer end, now we
147 * must flush only from the beginning to ->tail.
149 line->head = line->buffer;
156 count = line->tail - line->head;
157 n = write_chan(line->chan_out, line->head, count,
158 line->driver->write_irq);
164 return line->head == line->tail;
167 void line_flush_buffer(struct tty_struct *tty)
169 struct line *line = tty->driver_data;
172 spin_lock_irqsave(&line->lock, flags);
174 spin_unlock_irqrestore(&line->lock, flags);
178 * We map both ->flush_chars and ->put_char (which go in pair) onto
179 * ->flush_buffer and ->write. Hope it's not that bad.
181 void line_flush_chars(struct tty_struct *tty)
183 line_flush_buffer(tty);
186 int line_put_char(struct tty_struct *tty, unsigned char ch)
188 return line_write(tty, &ch, sizeof(ch));
191 int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
193 struct line *line = tty->driver_data;
197 spin_lock_irqsave(&line->lock, flags);
198 if (line->head != line->tail)
199 ret = buffer_data(line, buf, len);
201 n = write_chan(line->chan_out, buf, len,
202 line->driver->write_irq);
211 ret += buffer_data(line, buf + n, len);
214 spin_unlock_irqrestore(&line->lock, flags);
218 void line_set_termios(struct tty_struct *tty, struct ktermios * old)
223 void line_throttle(struct tty_struct *tty)
225 struct line *line = tty->driver_data;
227 deactivate_chan(line->chan_in, line->driver->read_irq);
231 void line_unthrottle(struct tty_struct *tty)
233 struct line *line = tty->driver_data;
236 chan_interrupt(line, line->driver->read_irq);
239 * Maybe there is enough stuff pending that calling the interrupt
240 * throttles us again. In this case, line->throttled will be 1
241 * again and we shouldn't turn the interrupt back on.
243 if (!line->throttled)
244 reactivate_chan(line->chan_in, line->driver->read_irq);
247 static irqreturn_t line_write_interrupt(int irq, void *data)
249 struct chan *chan = data;
250 struct line *line = chan->line;
254 * Interrupts are disabled here because genirq keep irqs disabled when
255 * calling the action handler.
258 spin_lock(&line->lock);
259 err = flush_buffer(line);
261 spin_unlock(&line->lock);
263 } else if (err < 0) {
264 line->head = line->buffer;
265 line->tail = line->buffer;
267 spin_unlock(&line->lock);
269 tty_port_tty_wakeup(&line->port);
274 int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
276 const struct line_driver *driver = line->driver;
280 err = um_request_irq(driver->read_irq, fd, IRQ_READ,
281 line_interrupt, IRQF_SHARED,
282 driver->read_irq_name, data);
286 err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
287 line_write_interrupt, IRQF_SHARED,
288 driver->write_irq_name, data);
292 static int line_activate(struct tty_port *port, struct tty_struct *tty)
295 struct line *line = tty->driver_data;
297 ret = enable_chan(line);
302 chan_enable_winch(line->chan_out, port);
306 chan_window_size(line, &tty->winsize.ws_row,
307 &tty->winsize.ws_col);
312 static void unregister_winch(struct tty_struct *tty);
314 static void line_destruct(struct tty_port *port)
316 struct tty_struct *tty = tty_port_tty_get(port);
317 struct line *line = tty->driver_data;
320 unregister_winch(tty);
325 static const struct tty_port_operations line_port_ops = {
326 .activate = line_activate,
327 .destruct = line_destruct,
330 int line_open(struct tty_struct *tty, struct file *filp)
332 struct line *line = tty->driver_data;
334 return tty_port_open(&line->port, tty, filp);
337 int line_install(struct tty_driver *driver, struct tty_struct *tty,
342 ret = tty_standard_install(driver, tty);
346 tty->driver_data = line;
351 void line_close(struct tty_struct *tty, struct file * filp)
353 struct line *line = tty->driver_data;
355 tty_port_close(&line->port, tty, filp);
358 void line_hangup(struct tty_struct *tty)
360 struct line *line = tty->driver_data;
362 tty_port_hangup(&line->port);
365 void close_lines(struct line *lines, int nlines)
369 for(i = 0; i < nlines; i++)
370 close_chan(&lines[i]);
373 int setup_one_line(struct line *lines, int n, char *init,
374 const struct chan_opts *opts, char **error_out)
376 struct line *line = &lines[n];
377 struct tty_driver *driver = line->driver->driver;
380 if (line->port.count) {
381 *error_out = "Device is already open";
385 if (!strcmp(init, "none")) {
388 kfree(line->init_str);
389 tty_unregister_device(driver, n);
390 parse_chan_pair(NULL, line, n, opts, error_out);
394 char *new = kstrdup(init, GFP_KERNEL);
396 *error_out = "Failed to allocate memory";
400 tty_unregister_device(driver, n);
401 kfree(line->init_str);
403 line->init_str = new;
405 err = parse_chan_pair(new, line, n, opts, error_out);
407 struct device *d = tty_port_register_device(&line->port,
410 *error_out = "Failed to register device";
412 parse_chan_pair(NULL, line, n, opts, error_out);
416 line->init_str = NULL;
426 * Common setup code for both startup command line and mconsole initialization.
427 * @lines contains the array (of size @num) to modify;
428 * @init is the setup string;
429 * @error_out is an error string in the case of failure;
432 int line_setup(char **conf, unsigned int num, char **def,
433 char *init, char *name)
439 * We said con=/ssl= instead of con#=, so we are configuring all
445 unsigned n = simple_strtoul(init, &end, 0);
448 error = "Couldn't parse device number";
452 error = "Device number out of range";
460 printk(KERN_ERR "Failed to set up %s with "
461 "configuration string \"%s\" : %s\n", name, init, error);
465 int line_config(struct line *lines, unsigned int num, char *str,
466 const struct chan_opts *opts, char **error_out)
472 *error_out = "Can't configure all devices from mconsole";
476 n = simple_strtoul(str, &end, 0);
478 *error_out = "Couldn't parse device number";
482 *error_out = "Device number out of range";
486 return setup_one_line(lines, n, end, opts, error_out);
489 int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
490 int size, char **error_out)
496 dev = simple_strtoul(name, &end, 0);
497 if ((*end != '\0') || (end == name)) {
498 *error_out = "line_get_config failed to parse device number";
502 if ((dev < 0) || (dev >= num)) {
503 *error_out = "device number out of range";
510 CONFIG_CHUNK(str, size, n, "none", 1);
512 struct tty_struct *tty = tty_port_tty_get(&line->port);
514 CONFIG_CHUNK(str, size, n, line->init_str, 1);
516 n = chan_config_string(line, str, size, error_out);
524 int line_id(char **str, int *start_out, int *end_out)
529 n = simple_strtoul(*str, &end, 0);
530 if ((*end != '\0') || (end == *str))
539 int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
542 *error_out = "Device number out of range";
545 return setup_one_line(lines, n, "none", NULL, error_out);
548 int register_lines(struct line_driver *line_driver,
549 const struct tty_operations *ops,
550 struct line *lines, int nlines)
552 struct tty_driver *driver = alloc_tty_driver(nlines);
559 driver->driver_name = line_driver->name;
560 driver->name = line_driver->device_name;
561 driver->major = line_driver->major;
562 driver->minor_start = line_driver->minor_start;
563 driver->type = line_driver->type;
564 driver->subtype = line_driver->subtype;
565 driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
566 driver->init_termios = tty_std_termios;
568 for (i = 0; i < nlines; i++) {
569 tty_port_init(&lines[i].port);
570 lines[i].port.ops = &line_port_ops;
571 spin_lock_init(&lines[i].lock);
572 lines[i].driver = line_driver;
573 INIT_LIST_HEAD(&lines[i].chan_list);
575 tty_set_operations(driver, ops);
577 err = tty_register_driver(driver);
579 printk(KERN_ERR "register_lines : can't register %s driver\n",
581 put_tty_driver(driver);
582 for (i = 0; i < nlines; i++)
583 tty_port_destroy(&lines[i].port);
587 line_driver->driver = driver;
588 mconsole_register_dev(&line_driver->mc);
592 static DEFINE_SPINLOCK(winch_handler_lock);
593 static LIST_HEAD(winch_handlers);
596 struct list_head list;
600 struct tty_port *port;
602 struct work_struct work;
605 static void __free_winch(struct work_struct *work)
607 struct winch *winch = container_of(work, struct winch, work);
608 um_free_irq(WINCH_IRQ, winch);
610 if (winch->pid != -1)
611 os_kill_process(winch->pid, 1);
612 if (winch->stack != 0)
613 free_stack(winch->stack, 0);
617 static void free_winch(struct winch *winch)
623 list_del(&winch->list);
624 __free_winch(&winch->work);
627 static irqreturn_t winch_interrupt(int irq, void *data)
629 struct winch *winch = data;
630 struct tty_struct *tty;
638 err = generic_read(fd, &c, NULL);
640 if (err != -EAGAIN) {
642 list_del(&winch->list);
644 printk(KERN_ERR "winch_interrupt : "
645 "read failed, errno = %d\n", -err);
646 printk(KERN_ERR "fd %d is losing SIGWINCH "
647 "support\n", winch->tty_fd);
648 INIT_WORK(&winch->work, __free_winch);
649 schedule_work(&winch->work);
655 tty = tty_port_tty_get(winch->port);
657 line = tty->driver_data;
659 chan_window_size(line, &tty->winsize.ws_row,
660 &tty->winsize.ws_col);
661 pgrp = tty_get_pgrp(tty);
663 kill_pgrp(pgrp, SIGWINCH, 1);
670 reactivate_fd(winch->fd, WINCH_IRQ);
674 void register_winch_irq(int fd, int tty_fd, int pid, struct tty_port *port,
679 winch = kmalloc(sizeof(*winch), GFP_KERNEL);
681 printk(KERN_ERR "register_winch_irq - kmalloc failed\n");
685 *winch = ((struct winch) { .list = LIST_HEAD_INIT(winch->list),
692 if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
693 IRQF_SHARED, "winch", winch) < 0) {
694 printk(KERN_ERR "register_winch_irq - failed to register "
699 spin_lock(&winch_handler_lock);
700 list_add(&winch->list, &winch_handlers);
701 spin_unlock(&winch_handler_lock);
708 os_kill_process(pid, 1);
711 free_stack(stack, 0);
714 static void unregister_winch(struct tty_struct *tty)
716 struct list_head *ele, *next;
718 struct tty_struct *wtty;
720 spin_lock(&winch_handler_lock);
722 list_for_each_safe(ele, next, &winch_handlers) {
723 winch = list_entry(ele, struct winch, list);
724 wtty = tty_port_tty_get(winch->port);
731 spin_unlock(&winch_handler_lock);
734 static void winch_cleanup(void)
736 struct list_head *ele, *next;
739 spin_lock(&winch_handler_lock);
741 list_for_each_safe(ele, next, &winch_handlers) {
742 winch = list_entry(ele, struct winch, list);
746 spin_unlock(&winch_handler_lock);
748 __uml_exitcall(winch_cleanup);
750 char *add_xterm_umid(char *base)
759 len = strlen(base) + strlen(" ()") + strlen(umid) + 1;
760 title = kmalloc(len, GFP_KERNEL);
762 printk(KERN_ERR "Failed to allocate buffer for xterm title\n");
766 snprintf(title, len, "%s (%s)", base, umid);