1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
22 	struct line *line = chan->line;  in line_interrupt()  local
24 	if (line)  in line_interrupt()
25 		chan_interrupt(line, irq);  in line_interrupt()
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)  in write_room()  argument
39 	if (line->buffer == NULL)  in write_room()
40 		return LINE_BUFSIZE - 1;  in write_room()
43 	n = line->head - line->tail;  in write_room()
47 	return n - 1;  in write_room()
52 	struct line *line = tty->driver_data;  in line_write_room()  local
56 	spin_lock_irqsave(&line->lock, flags);  in line_write_room()
57 	room = write_room(line);  in line_write_room()
58 	spin_unlock_irqrestore(&line->lock, flags);  in line_write_room()
65 	struct line *line = tty->driver_data;  in line_chars_in_buffer()  local
69 	spin_lock_irqsave(&line->lock, flags);  in line_chars_in_buffer()
71 	ret = LINE_BUFSIZE - (write_room(line) + 1);  in line_chars_in_buffer()
72 	spin_unlock_irqrestore(&line->lock, flags);  in line_chars_in_buffer()
79  * this line.
84  * Must be called while holding line->lock!
86 static int buffer_data(struct line *line, const char *buf, int len)  in buffer_data()  argument
90 	if (line->buffer == NULL) {  in buffer_data()
91 		line->buffer = kmalloc(LINE_BUFSIZE, GFP_ATOMIC);  in buffer_data()
92 		if (line->buffer == NULL) {  in buffer_data()
93 			printk(KERN_ERR "buffer_data - atomic allocation "  in buffer_data()
97 		line->head = line->buffer;  in buffer_data()
98 		line->tail = line->buffer;  in buffer_data()
101 	room = write_room(line);  in buffer_data()
104 	end = line->buffer + LINE_BUFSIZE - line->tail;  in buffer_data()
107 		memcpy(line->tail, buf, len);  in buffer_data()
108 		line->tail += len;  in buffer_data()
112 		memcpy(line->tail, buf, end);  in buffer_data()
114 		memcpy(line->buffer, buf, len - end);  in buffer_data()
115 		line->tail = line->buffer + len - end;  in buffer_data()
123  * called, passing it line->head as buffer, and an appropriate count.
127  * and -errno when an error occurred.
129  * Must be called while holding line->lock!*/
130 static int flush_buffer(struct line *line)  in flush_buffer()  argument
134 	if ((line->buffer == NULL) || (line->head == line->tail))  in flush_buffer()
137 	if (line->tail < line->head) {  in flush_buffer()
138 		/* line->buffer + LINE_BUFSIZE is the end of the buffer! */  in flush_buffer()
139 		count = line->buffer + LINE_BUFSIZE - line->head;  in flush_buffer()
141 		n = write_chan(line->chan_out, line->head, count,  in flush_buffer()
142 			       line->driver->write_irq);  in flush_buffer()
147 			 * We have flushed from ->head to buffer end, now we  in flush_buffer()
148 			 * must flush only from the beginning to ->tail.  in flush_buffer()
150 			line->head = line->buffer;  in flush_buffer()
152 			line->head += n;  in flush_buffer()
157 	count = line->tail - line->head;  in flush_buffer()
158 	n = write_chan(line->chan_out, line->head, count,  in flush_buffer()
159 		       line->driver->write_irq);  in flush_buffer()
164 	line->head += n;  in flush_buffer()
165 	return line->head == line->tail;  in flush_buffer()
170 	struct line *line = tty->driver_data;  in line_flush_buffer()  local
173 	spin_lock_irqsave(&line->lock, flags);  in line_flush_buffer()
174 	flush_buffer(line);  in line_flush_buffer()
175 	spin_unlock_irqrestore(&line->lock, flags);  in line_flush_buffer()
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.
189 	struct line *line = tty->driver_data;  in line_write()  local
193 	spin_lock_irqsave(&line->lock, flags);  in line_write()
194 	if (line->head != line->tail)  in line_write()
195 		ret = buffer_data(line, buf, len);  in line_write()
197 		n = write_chan(line->chan_out, buf, len,  in line_write()
198 			       line->driver->write_irq);  in line_write()
204 		len -= n;  in line_write()
207 			ret += buffer_data(line, buf + n, len);  in line_write()
210 	spin_unlock_irqrestore(&line->lock, flags);  in line_write()
221 	struct line *line = tty->driver_data;  in line_throttle()  local
223 	deactivate_chan(line->chan_in, line->driver->read_irq);  in line_throttle()
224 	line->throttled = 1;  in line_throttle()
229 	struct line *line = tty->driver_data;  in line_unthrottle()  local
231 	line->throttled = 0;  in line_unthrottle()
232 	chan_interrupt(line, line->driver->read_irq);  in line_unthrottle()
238 	struct line *line = chan->line;  in line_write_interrupt()  local
246 	spin_lock(&line->lock);  in line_write_interrupt()
247 	err = flush_buffer(line);  in line_write_interrupt()
249 		spin_unlock(&line->lock);  in line_write_interrupt()
251 	} else if ((err < 0) && (err != -EAGAIN)) {  in line_write_interrupt()
252 		line->head = line->buffer;  in line_write_interrupt()
253 		line->tail = line->buffer;  in line_write_interrupt()
255 	spin_unlock(&line->lock);  in line_write_interrupt()
257 	tty_port_tty_wakeup(&line->port);  in line_write_interrupt()
262 int line_setup_irq(int fd, int input, int output, struct line *line, void *data)  in line_setup_irq()  argument
264 	const struct line_driver *driver = line->driver;  in line_setup_irq()
268 		err = um_request_irq(driver->read_irq, fd, IRQ_READ,  in line_setup_irq()
270 				     driver->read_irq_name, data);  in line_setup_irq()
274 		err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,  in line_setup_irq()
276 				     driver->write_irq_name, data);  in line_setup_irq()
283 	struct line *line = tty->driver_data;  in line_activate()  local
285 	ret = enable_chan(line);  in line_activate()
289 	if (!line->sigio) {  in line_activate()
290 		chan_enable_winch(line->chan_out, port);  in line_activate()
291 		line->sigio = 1;  in line_activate()
294 	chan_window_size(line, &tty->winsize.ws_row,  in line_activate()
295 		&tty->winsize.ws_col);  in line_activate()
305 	struct line *line = tty->driver_data;  in line_destruct()  local
307 	if (line->sigio) {  in line_destruct()
309 		line->sigio = 0;  in line_destruct()
320 	struct line *line = tty->driver_data;  in line_open()  local
322 	return tty_port_open(&line->port, tty, filp);  in line_open()
326 		 struct line *line)  in line_install()  argument
334 	tty->driver_data = line;  in line_install()
341 	struct line *line = tty->driver_data;  in line_close()  local
343 	tty_port_close(&line->port, tty, filp);  in line_close()
348 	struct line *line = tty->driver_data;  in line_hangup()  local
350 	tty_port_hangup(&line->port);  in line_hangup()
353 void close_lines(struct line *lines, int nlines)  in close_lines()
361 int setup_one_line(struct line *lines, int n, char *init,  in setup_one_line()
364 	struct line *line = &lines[n];  in setup_one_line()  local
365 	struct tty_driver *driver = line->driver->driver;  in setup_one_line()
366 	int err = -EINVAL;  in setup_one_line()
368 	if (line->port.count) {  in setup_one_line()
374 		if (line->valid) {  in setup_one_line()
375 			line->valid = 0;  in setup_one_line()
376 			kfree(line->init_str);  in setup_one_line()
378 			parse_chan_pair(NULL, line, n, opts, error_out);  in setup_one_line()
385 			return -ENOMEM;  in setup_one_line()
387 		if (line->valid) {  in setup_one_line()
389 			kfree(line->init_str);  in setup_one_line()
391 		line->init_str = new;  in setup_one_line()
392 		line->valid = 1;  in setup_one_line()
393 		err = parse_chan_pair(new, line, n, opts, error_out);  in setup_one_line()
395 			struct device *d = tty_port_register_device(&line->port,  in setup_one_line()
400 				parse_chan_pair(NULL, line, n, opts, error_out);  in setup_one_line()
404 			line->init_str = NULL;  in setup_one_line()
405 			line->valid = 0;  in setup_one_line()
414  * Common setup code for both startup command line and mconsole initialization.
421 	       char *init, char *name)  in line_setup()  argument
449 	       "configuration string \"%s\" : %s\n", name, init, error);  in line_setup()
450 	return -EINVAL;  in line_setup()
453 int line_config(struct line *lines, unsigned int num, char *str,  in line_config()
461 		return -EINVAL;  in line_config()
467 		return -EINVAL;  in line_config()
471 		return -EINVAL;  in line_config()
477 int line_get_config(char *name, struct line *lines, unsigned int num, char *str,  in line_get_config()  argument
480 	struct line *line;  in line_get_config()  local
484 	dev = simple_strtoul(name, &end, 0);  in line_get_config()
485 	if ((*end != '\0') || (end == name)) {  in line_get_config()
495 	line = &lines[dev];  in line_get_config()
497 	if (!line->valid)  in line_get_config()
500 		struct tty_struct *tty = tty_port_tty_get(&line->port);  in line_get_config()
502 			CONFIG_CHUNK(str, size, n, line->init_str, 1);  in line_get_config()
504 			n = chan_config_string(line, str, size, error_out);  in line_get_config()
519 		return -1;  in line_id()
527 int line_remove(struct line *lines, unsigned int num, int n, char **error_out)  in line_remove()
531 		return -EINVAL;  in line_remove()
538 		   struct line *lines, int nlines)  in register_lines()
545 		return -ENOMEM;  in register_lines()
547 	driver->driver_name = line_driver->name;  in register_lines()
548 	driver->name = line_driver->device_name;  in register_lines()
549 	driver->major = line_driver->major;  in register_lines()
550 	driver->minor_start = line_driver->minor_start;  in register_lines()
551 	driver->type = line_driver->type;  in register_lines()
552 	driver->subtype = line_driver->subtype;  in register_lines()
553 	driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;  in register_lines()
554 	driver->init_termios = tty_std_termios;  in register_lines()
568 		       line_driver->name);  in register_lines()
575 	line_driver->driver = driver;  in register_lines()
576 	mconsole_register_dev(&line_driver->mc);  in register_lines()
598 	if (winch->pid != -1)  in __free_winch()
599 		os_kill_process(winch->pid, 1);  in __free_winch()
600 	if (winch->stack != 0)  in __free_winch()
601 		free_stack(winch->stack, 0);  in __free_winch()
607 	int fd = winch->fd;  in free_winch()
608 	winch->fd = -1;  in free_winch()
609 	if (fd != -1)  in free_winch()
611 	list_del(&winch->list);  in free_winch()
612 	__free_winch(&winch->work);  in free_winch()
619 	struct line *line;  in winch_interrupt()  local
620 	int fd = winch->fd;  in winch_interrupt()
625 	if (fd != -1) {  in winch_interrupt()
628 			if (err != -EAGAIN) {  in winch_interrupt()
629 				winch->fd = -1;  in winch_interrupt()
630 				list_del(&winch->list);  in winch_interrupt()
633 				       "read failed, errno = %d\n", -err);  in winch_interrupt()
635 				       "support\n", winch->tty_fd);  in winch_interrupt()
636 				INIT_WORK(&winch->work, __free_winch);  in winch_interrupt()
637 				schedule_work(&winch->work);  in winch_interrupt()
643 	tty = tty_port_tty_get(winch->port);  in winch_interrupt()
645 		line = tty->driver_data;  in winch_interrupt()
646 		if (line != NULL) {  in winch_interrupt()
647 			chan_window_size(line, &tty->winsize.ws_row,  in winch_interrupt()
648 					 &tty->winsize.ws_col);  in winch_interrupt()
667 		printk(KERN_ERR "register_winch_irq - kmalloc failed\n");  in register_winch_irq()
671 	*winch = ((struct winch) { .list  	= LIST_HEAD_INIT(winch->list),  in register_winch_irq()
680 		printk(KERN_ERR "register_winch_irq - failed to register "  in register_winch_irq()
686 	list_add(&winch->list, &winch_handlers);  in register_winch_irq()
710 		wtty = tty_port_tty_get(winch->port);  in unregister_winch()