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"
10 #include "chan_kern.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
->chan_list
, &line
->task
, line
->tty
, irq
);
28 static void line_timer_cb(struct work_struct
*work
)
30 struct line
*line
= container_of(work
, struct line
, task
.work
);
33 chan_interrupt(&line
->chan_list
, &line
->task
, line
->tty
,
34 line
->driver
->read_irq
);
38 * Returns the free space inside the ring buffer of this line.
40 * Should be called while holding line->lock (this does not modify data).
42 static int write_room(struct line
*line
)
46 if (line
->buffer
== NULL
)
47 return LINE_BUFSIZE
- 1;
49 /* This is for the case where the buffer is wrapped! */
50 n
= line
->head
- line
->tail
;
53 n
+= LINE_BUFSIZE
; /* The other case */
57 int line_write_room(struct tty_struct
*tty
)
59 struct line
*line
= tty
->driver_data
;
63 spin_lock_irqsave(&line
->lock
, flags
);
64 room
= write_room(line
);
65 spin_unlock_irqrestore(&line
->lock
, flags
);
70 int line_chars_in_buffer(struct tty_struct
*tty
)
72 struct line
*line
= tty
->driver_data
;
76 spin_lock_irqsave(&line
->lock
, flags
);
77 /* write_room subtracts 1 for the needed NULL, so we readd it.*/
78 ret
= LINE_BUFSIZE
- (write_room(line
) + 1);
79 spin_unlock_irqrestore(&line
->lock
, flags
);
85 * This copies the content of buf into the circular buffer associated with
87 * The return value is the number of characters actually copied, i.e. the ones
88 * for which there was space: this function is not supposed to ever flush out
89 * the circular buffer.
91 * Must be called while holding line->lock!
93 static int buffer_data(struct line
*line
, const char *buf
, int len
)
97 if (line
->buffer
== NULL
) {
98 line
->buffer
= kmalloc(LINE_BUFSIZE
, GFP_ATOMIC
);
99 if (line
->buffer
== NULL
) {
100 printk(KERN_ERR
"buffer_data - atomic allocation "
104 line
->head
= line
->buffer
;
105 line
->tail
= line
->buffer
;
108 room
= write_room(line
);
109 len
= (len
> room
) ? room
: len
;
111 end
= line
->buffer
+ LINE_BUFSIZE
- line
->tail
;
114 memcpy(line
->tail
, buf
, len
);
118 /* The circular buffer is wrapping */
119 memcpy(line
->tail
, buf
, end
);
121 memcpy(line
->buffer
, buf
, len
- end
);
122 line
->tail
= line
->buffer
+ len
- end
;
129 * Flushes the ring buffer to the output channels. That is, write_chan is
130 * called, passing it line->head as buffer, and an appropriate count.
132 * On exit, returns 1 when the buffer is empty,
133 * 0 when the buffer is not empty on exit,
134 * and -errno when an error occurred.
136 * Must be called while holding line->lock!*/
137 static int flush_buffer(struct line
*line
)
141 if ((line
->buffer
== NULL
) || (line
->head
== line
->tail
))
144 if (line
->tail
< line
->head
) {
145 /* line->buffer + LINE_BUFSIZE is the end of the buffer! */
146 count
= line
->buffer
+ LINE_BUFSIZE
- line
->head
;
148 n
= write_chan(&line
->chan_list
, line
->head
, count
,
149 line
->driver
->write_irq
);
154 * We have flushed from ->head to buffer end, now we
155 * must flush only from the beginning to ->tail.
157 line
->head
= line
->buffer
;
164 count
= line
->tail
- line
->head
;
165 n
= write_chan(&line
->chan_list
, line
->head
, count
,
166 line
->driver
->write_irq
);
172 return line
->head
== line
->tail
;
175 void line_flush_buffer(struct tty_struct
*tty
)
177 struct line
*line
= tty
->driver_data
;
181 spin_lock_irqsave(&line
->lock
, flags
);
182 err
= flush_buffer(line
);
183 spin_unlock_irqrestore(&line
->lock
, flags
);
187 * We map both ->flush_chars and ->put_char (which go in pair) onto
188 * ->flush_buffer and ->write. Hope it's not that bad.
190 void line_flush_chars(struct tty_struct
*tty
)
192 line_flush_buffer(tty
);
195 int line_put_char(struct tty_struct
*tty
, unsigned char ch
)
197 return line_write(tty
, &ch
, sizeof(ch
));
200 int line_write(struct tty_struct
*tty
, const unsigned char *buf
, int len
)
202 struct line
*line
= tty
->driver_data
;
206 spin_lock_irqsave(&line
->lock
, flags
);
207 if (line
->head
!= line
->tail
)
208 ret
= buffer_data(line
, buf
, len
);
210 n
= write_chan(&line
->chan_list
, buf
, len
,
211 line
->driver
->write_irq
);
220 ret
+= buffer_data(line
, buf
+ n
, len
);
223 spin_unlock_irqrestore(&line
->lock
, flags
);
227 void line_set_termios(struct tty_struct
*tty
, struct ktermios
* old
)
232 static const struct {
237 /* don't print these, they flood the log ... */
238 { TCGETS
, NULL
, "TCGETS" },
239 { TCSETS
, NULL
, "TCSETS" },
240 { TCSETSW
, NULL
, "TCSETSW" },
241 { TCFLSH
, NULL
, "TCFLSH" },
242 { TCSBRK
, NULL
, "TCSBRK" },
244 /* general tty stuff */
245 { TCSETSF
, KERN_DEBUG
, "TCSETSF" },
246 { TCGETA
, KERN_DEBUG
, "TCGETA" },
247 { TIOCMGET
, KERN_DEBUG
, "TIOCMGET" },
248 { TCSBRKP
, KERN_DEBUG
, "TCSBRKP" },
249 { TIOCMSET
, KERN_DEBUG
, "TIOCMSET" },
251 /* linux-specific ones */
252 { TIOCLINUX
, KERN_INFO
, "TIOCLINUX" },
253 { KDGKBMODE
, KERN_INFO
, "KDGKBMODE" },
254 { KDGKBTYPE
, KERN_INFO
, "KDGKBTYPE" },
255 { KDSIGACCEPT
, KERN_INFO
, "KDSIGACCEPT" },
258 int line_ioctl(struct tty_struct
*tty
, struct file
* file
,
259 unsigned int cmd
, unsigned long arg
)
279 /* Note: these are out of date as we now have TCGETS2 etc but this
280 whole lot should probably go away */
300 for (i
= 0; i
< ARRAY_SIZE(tty_ioctls
); i
++)
301 if (cmd
== tty_ioctls
[i
].cmd
)
303 if (i
== ARRAY_SIZE(tty_ioctls
)) {
304 printk(KERN_ERR
"%s: %s: unknown ioctl: 0x%x\n",
305 __func__
, tty
->name
, cmd
);
313 void line_throttle(struct tty_struct
*tty
)
315 struct line
*line
= tty
->driver_data
;
317 deactivate_chan(&line
->chan_list
, line
->driver
->read_irq
);
321 void line_unthrottle(struct tty_struct
*tty
)
323 struct line
*line
= tty
->driver_data
;
326 chan_interrupt(&line
->chan_list
, &line
->task
, tty
,
327 line
->driver
->read_irq
);
330 * Maybe there is enough stuff pending that calling the interrupt
331 * throttles us again. In this case, line->throttled will be 1
332 * again and we shouldn't turn the interrupt back on.
334 if (!line
->throttled
)
335 reactivate_chan(&line
->chan_list
, line
->driver
->read_irq
);
338 static irqreturn_t
line_write_interrupt(int irq
, void *data
)
340 struct chan
*chan
= data
;
341 struct line
*line
= chan
->line
;
342 struct tty_struct
*tty
= line
->tty
;
346 * Interrupts are disabled here because we registered the interrupt with
347 * IRQF_DISABLED (see line_setup_irq).
350 spin_lock(&line
->lock
);
351 err
= flush_buffer(line
);
354 } else if (err
< 0) {
355 line
->head
= line
->buffer
;
356 line
->tail
= line
->buffer
;
358 spin_unlock(&line
->lock
);
367 int line_setup_irq(int fd
, int input
, int output
, struct line
*line
, void *data
)
369 const struct line_driver
*driver
= line
->driver
;
370 int err
= 0, flags
= IRQF_DISABLED
| IRQF_SHARED
| IRQF_SAMPLE_RANDOM
;
373 err
= um_request_irq(driver
->read_irq
, fd
, IRQ_READ
,
374 line_interrupt
, flags
,
375 driver
->read_irq_name
, data
);
379 err
= um_request_irq(driver
->write_irq
, fd
, IRQ_WRITE
,
380 line_write_interrupt
, flags
,
381 driver
->write_irq_name
, data
);
387 * Normally, a driver like this can rely mostly on the tty layer
388 * locking, particularly when it comes to the driver structure.
389 * However, in this case, mconsole requests can come in "from the
390 * side", and race with opens and closes.
392 * mconsole config requests will want to be sure the device isn't in
393 * use, and get_config, open, and close will want a stable
394 * configuration. The checking and modification of the configuration
395 * is done under a spinlock. Checking whether the device is in use is
396 * line->tty->count > 1, also under the spinlock.
398 * tty->count serves to decide whether the device should be enabled or
399 * disabled on the host. If it's equal to 1, then we are doing the
400 * first open or last close. Otherwise, open and close just return.
403 int line_open(struct line
*lines
, struct tty_struct
*tty
)
405 struct line
*line
= &lines
[tty
->index
];
408 spin_lock(&line
->count_lock
);
416 spin_unlock(&line
->count_lock
);
418 tty
->driver_data
= line
;
421 err
= enable_chan(line
);
425 INIT_DELAYED_WORK(&line
->task
, line_timer_cb
);
428 chan_enable_winch(&line
->chan_list
, tty
);
432 chan_window_size(&line
->chan_list
, &tty
->winsize
.ws_row
,
433 &tty
->winsize
.ws_col
);
438 spin_unlock(&line
->count_lock
);
442 static void unregister_winch(struct tty_struct
*tty
);
444 void line_close(struct tty_struct
*tty
, struct file
* filp
)
446 struct line
*line
= tty
->driver_data
;
449 * If line_open fails (and tty->driver_data is never set),
450 * tty_open will call line_close. So just return in this case.
455 /* We ignore the error anyway! */
458 spin_lock(&line
->count_lock
);
465 spin_unlock(&line
->count_lock
);
468 tty
->driver_data
= NULL
;
471 unregister_winch(tty
);
478 spin_unlock(&line
->count_lock
);
481 void close_lines(struct line
*lines
, int nlines
)
485 for(i
= 0; i
< nlines
; i
++)
486 close_chan(&lines
[i
].chan_list
, 0);
489 static int setup_one_line(struct line
*lines
, int n
, char *init
, int init_prio
,
492 struct line
*line
= &lines
[n
];
495 spin_lock(&line
->count_lock
);
497 if (line
->tty
!= NULL
) {
498 *error_out
= "Device is already open";
502 if (line
->init_pri
<= init_prio
) {
503 line
->init_pri
= init_prio
;
504 if (!strcmp(init
, "none"))
507 line
->init_str
= init
;
513 spin_unlock(&line
->count_lock
);
518 * Common setup code for both startup command line and mconsole initialization.
519 * @lines contains the array (of size @num) to modify;
520 * @init is the setup string;
521 * @error_out is an error string in the case of failure;
524 int line_setup(struct line
*lines
, unsigned int num
, char *init
,
532 * We said con=/ssl= instead of con#=, so we are configuring all
538 n
= simple_strtoul(init
, &end
, 0);
540 *error_out
= "Couldn't parse device number";
547 if (n
>= (signed int) num
) {
548 *error_out
= "Device number out of range";
552 err
= setup_one_line(lines
, n
, init
, INIT_ONE
, error_out
);
557 for(i
= 0; i
< num
; i
++) {
558 err
= setup_one_line(lines
, i
, init
, INIT_ALL
,
564 return n
== -1 ? num
: n
;
567 int line_config(struct line
*lines
, unsigned int num
, char *str
,
568 const struct chan_opts
*opts
, char **error_out
)
575 *error_out
= "Can't configure all devices from mconsole";
579 new = kstrdup(str
, GFP_KERNEL
);
581 *error_out
= "Failed to allocate memory";
584 n
= line_setup(lines
, num
, new, error_out
);
589 return parse_chan_pair(line
->init_str
, line
, n
, opts
, error_out
);
592 int line_get_config(char *name
, struct line
*lines
, unsigned int num
, char *str
,
593 int size
, char **error_out
)
599 dev
= simple_strtoul(name
, &end
, 0);
600 if ((*end
!= '\0') || (end
== name
)) {
601 *error_out
= "line_get_config failed to parse device number";
605 if ((dev
< 0) || (dev
>= num
)) {
606 *error_out
= "device number out of range";
612 spin_lock(&line
->count_lock
);
614 CONFIG_CHUNK(str
, size
, n
, "none", 1);
615 else if (line
->tty
== NULL
)
616 CONFIG_CHUNK(str
, size
, n
, line
->init_str
, 1);
617 else n
= chan_config_string(&line
->chan_list
, str
, size
, error_out
);
618 spin_unlock(&line
->count_lock
);
623 int line_id(char **str
, int *start_out
, int *end_out
)
628 n
= simple_strtoul(*str
, &end
, 0);
629 if ((*end
!= '\0') || (end
== *str
))
638 int line_remove(struct line
*lines
, unsigned int num
, int n
, char **error_out
)
641 char config
[sizeof("conxxxx=none\0")];
643 sprintf(config
, "%d=none", n
);
644 err
= line_setup(lines
, num
, config
, error_out
);
650 struct tty_driver
*register_lines(struct line_driver
*line_driver
,
651 const struct tty_operations
*ops
,
652 struct line
*lines
, int nlines
)
655 struct tty_driver
*driver
= alloc_tty_driver(nlines
);
660 driver
->driver_name
= line_driver
->name
;
661 driver
->name
= line_driver
->device_name
;
662 driver
->major
= line_driver
->major
;
663 driver
->minor_start
= line_driver
->minor_start
;
664 driver
->type
= line_driver
->type
;
665 driver
->subtype
= line_driver
->subtype
;
666 driver
->flags
= TTY_DRIVER_REAL_RAW
;
667 driver
->init_termios
= tty_std_termios
;
668 tty_set_operations(driver
, ops
);
670 if (tty_register_driver(driver
)) {
671 printk(KERN_ERR
"register_lines : can't register %s driver\n",
673 put_tty_driver(driver
);
677 for(i
= 0; i
< nlines
; i
++) {
679 tty_unregister_device(driver
, i
);
682 mconsole_register_dev(&line_driver
->mc
);
686 static DEFINE_SPINLOCK(winch_handler_lock
);
687 static LIST_HEAD(winch_handlers
);
689 void lines_init(struct line
*lines
, int nlines
, struct chan_opts
*opts
)
695 for(i
= 0; i
< nlines
; i
++) {
697 INIT_LIST_HEAD(&line
->chan_list
);
699 if (line
->init_str
== NULL
)
702 line
->init_str
= kstrdup(line
->init_str
, GFP_KERNEL
);
703 if (line
->init_str
== NULL
)
704 printk(KERN_ERR
"lines_init - kstrdup returned NULL\n");
706 if (parse_chan_pair(line
->init_str
, line
, i
, opts
, &error
)) {
707 printk(KERN_ERR
"parse_chan_pair failed for "
708 "device %d : %s\n", i
, error
);
715 struct list_head list
;
719 struct tty_struct
*tty
;
723 static void free_winch(struct winch
*winch
, int free_irq_ok
)
726 free_irq(WINCH_IRQ
, winch
);
728 list_del(&winch
->list
);
730 if (winch
->pid
!= -1)
731 os_kill_process(winch
->pid
, 1);
733 os_close_file(winch
->fd
);
734 if (winch
->stack
!= 0)
735 free_stack(winch
->stack
, 0);
739 static irqreturn_t
winch_interrupt(int irq
, void *data
)
741 struct winch
*winch
= data
;
742 struct tty_struct
*tty
;
747 if (winch
->fd
!= -1) {
748 err
= generic_read(winch
->fd
, &c
, NULL
);
750 if (err
!= -EAGAIN
) {
751 printk(KERN_ERR
"winch_interrupt : "
752 "read failed, errno = %d\n", -err
);
753 printk(KERN_ERR
"fd %d is losing SIGWINCH "
754 "support\n", winch
->tty_fd
);
755 free_winch(winch
, 0);
763 line
= tty
->driver_data
;
765 chan_window_size(&line
->chan_list
, &tty
->winsize
.ws_row
,
766 &tty
->winsize
.ws_col
);
767 kill_pgrp(tty
->pgrp
, SIGWINCH
, 1);
772 reactivate_fd(winch
->fd
, WINCH_IRQ
);
776 void register_winch_irq(int fd
, int tty_fd
, int pid
, struct tty_struct
*tty
,
781 winch
= kmalloc(sizeof(*winch
), GFP_KERNEL
);
783 printk(KERN_ERR
"register_winch_irq - kmalloc failed\n");
787 *winch
= ((struct winch
) { .list
= LIST_HEAD_INIT(winch
->list
),
794 if (um_request_irq(WINCH_IRQ
, fd
, IRQ_READ
, winch_interrupt
,
795 IRQF_DISABLED
| IRQF_SHARED
| IRQF_SAMPLE_RANDOM
,
796 "winch", winch
) < 0) {
797 printk(KERN_ERR
"register_winch_irq - failed to register "
802 spin_lock(&winch_handler_lock
);
803 list_add(&winch
->list
, &winch_handlers
);
804 spin_unlock(&winch_handler_lock
);
811 os_kill_process(pid
, 1);
814 free_stack(stack
, 0);
817 static void unregister_winch(struct tty_struct
*tty
)
819 struct list_head
*ele
;
822 spin_lock(&winch_handler_lock
);
824 list_for_each(ele
, &winch_handlers
) {
825 winch
= list_entry(ele
, struct winch
, list
);
826 if (winch
->tty
== tty
) {
827 free_winch(winch
, 1);
831 spin_unlock(&winch_handler_lock
);
834 static void winch_cleanup(void)
836 struct list_head
*ele
, *next
;
839 spin_lock(&winch_handler_lock
);
841 list_for_each_safe(ele
, next
, &winch_handlers
) {
842 winch
= list_entry(ele
, struct winch
, list
);
843 free_winch(winch
, 1);
846 spin_unlock(&winch_handler_lock
);
848 __uml_exitcall(winch_cleanup
);
850 char *add_xterm_umid(char *base
)
859 len
= strlen(base
) + strlen(" ()") + strlen(umid
) + 1;
860 title
= kmalloc(len
, GFP_KERNEL
);
862 printk(KERN_ERR
"Failed to allocate buffer for xterm title\n");
866 snprintf(title
, len
, "%s (%s)", base
, umid
);