2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
6 #include "linux/irqreturn.h"
11 #include "kern_util.h"
14 #define LINE_BUFSIZE 4096
16 static irqreturn_t
line_interrupt(int irq
, void *data
)
18 struct chan
*chan
= data
;
19 struct line
*line
= chan
->line
;
20 struct tty_struct
*tty
= line
->tty
;
23 chan_interrupt(&line
->chan_list
, &line
->task
, tty
, irq
);
27 static void line_timer_cb(struct work_struct
*work
)
29 struct line
*line
= container_of(work
, struct line
, task
.work
);
32 chan_interrupt(&line
->chan_list
, &line
->task
, line
->tty
,
33 line
->driver
->read_irq
);
37 * Returns the free space inside the ring buffer of this line.
39 * Should be called while holding line->lock (this does not modify data).
41 static int write_room(struct line
*line
)
45 if (line
->buffer
== NULL
)
46 return LINE_BUFSIZE
- 1;
48 /* This is for the case where the buffer is wrapped! */
49 n
= line
->head
- line
->tail
;
52 n
+= LINE_BUFSIZE
; /* The other case */
56 int line_write_room(struct tty_struct
*tty
)
58 struct line
*line
= tty
->driver_data
;
62 spin_lock_irqsave(&line
->lock
, flags
);
63 room
= write_room(line
);
64 spin_unlock_irqrestore(&line
->lock
, flags
);
69 int line_chars_in_buffer(struct tty_struct
*tty
)
71 struct line
*line
= tty
->driver_data
;
75 spin_lock_irqsave(&line
->lock
, flags
);
76 /* write_room subtracts 1 for the needed NULL, so we readd it.*/
77 ret
= LINE_BUFSIZE
- (write_room(line
) + 1);
78 spin_unlock_irqrestore(&line
->lock
, flags
);
84 * This copies the content of buf into the circular buffer associated with
86 * The return value is the number of characters actually copied, i.e. the ones
87 * for which there was space: this function is not supposed to ever flush out
88 * the circular buffer.
90 * Must be called while holding line->lock!
92 static int buffer_data(struct line
*line
, const char *buf
, int len
)
96 if (line
->buffer
== NULL
) {
97 line
->buffer
= kmalloc(LINE_BUFSIZE
, GFP_ATOMIC
);
98 if (line
->buffer
== NULL
) {
99 printk(KERN_ERR
"buffer_data - atomic allocation "
103 line
->head
= line
->buffer
;
104 line
->tail
= line
->buffer
;
107 room
= write_room(line
);
108 len
= (len
> room
) ? room
: len
;
110 end
= line
->buffer
+ LINE_BUFSIZE
- line
->tail
;
113 memcpy(line
->tail
, buf
, len
);
117 /* The circular buffer is wrapping */
118 memcpy(line
->tail
, buf
, end
);
120 memcpy(line
->buffer
, buf
, len
- end
);
121 line
->tail
= line
->buffer
+ len
- end
;
128 * Flushes the ring buffer to the output channels. That is, write_chan is
129 * called, passing it line->head as buffer, and an appropriate count.
131 * On exit, returns 1 when the buffer is empty,
132 * 0 when the buffer is not empty on exit,
133 * and -errno when an error occurred.
135 * Must be called while holding line->lock!*/
136 static int flush_buffer(struct line
*line
)
140 if ((line
->buffer
== NULL
) || (line
->head
== line
->tail
))
143 if (line
->tail
< line
->head
) {
144 /* line->buffer + LINE_BUFSIZE is the end of the buffer! */
145 count
= line
->buffer
+ LINE_BUFSIZE
- line
->head
;
147 n
= write_chan(&line
->chan_list
, line
->head
, count
,
148 line
->driver
->write_irq
);
153 * We have flushed from ->head to buffer end, now we
154 * must flush only from the beginning to ->tail.
156 line
->head
= line
->buffer
;
163 count
= line
->tail
- line
->head
;
164 n
= write_chan(&line
->chan_list
, line
->head
, count
,
165 line
->driver
->write_irq
);
171 return line
->head
== line
->tail
;
174 void line_flush_buffer(struct tty_struct
*tty
)
176 struct line
*line
= tty
->driver_data
;
180 spin_lock_irqsave(&line
->lock
, flags
);
181 err
= flush_buffer(line
);
182 spin_unlock_irqrestore(&line
->lock
, flags
);
186 * We map both ->flush_chars and ->put_char (which go in pair) onto
187 * ->flush_buffer and ->write. Hope it's not that bad.
189 void line_flush_chars(struct tty_struct
*tty
)
191 line_flush_buffer(tty
);
194 int line_put_char(struct tty_struct
*tty
, unsigned char ch
)
196 return line_write(tty
, &ch
, sizeof(ch
));
199 int line_write(struct tty_struct
*tty
, const unsigned char *buf
, int len
)
201 struct line
*line
= tty
->driver_data
;
205 spin_lock_irqsave(&line
->lock
, flags
);
206 if (line
->head
!= line
->tail
)
207 ret
= buffer_data(line
, buf
, len
);
209 n
= write_chan(&line
->chan_list
, buf
, len
,
210 line
->driver
->write_irq
);
219 ret
+= buffer_data(line
, buf
+ n
, len
);
222 spin_unlock_irqrestore(&line
->lock
, flags
);
226 void line_set_termios(struct tty_struct
*tty
, struct ktermios
* old
)
231 static const struct {
236 /* don't print these, they flood the log ... */
237 { TCGETS
, NULL
, "TCGETS" },
238 { TCSETS
, NULL
, "TCSETS" },
239 { TCSETSW
, NULL
, "TCSETSW" },
240 { TCFLSH
, NULL
, "TCFLSH" },
241 { TCSBRK
, NULL
, "TCSBRK" },
243 /* general tty stuff */
244 { TCSETSF
, KERN_DEBUG
, "TCSETSF" },
245 { TCGETA
, KERN_DEBUG
, "TCGETA" },
246 { TIOCMGET
, KERN_DEBUG
, "TIOCMGET" },
247 { TCSBRKP
, KERN_DEBUG
, "TCSBRKP" },
248 { TIOCMSET
, KERN_DEBUG
, "TIOCMSET" },
250 /* linux-specific ones */
251 { TIOCLINUX
, KERN_INFO
, "TIOCLINUX" },
252 { KDGKBMODE
, KERN_INFO
, "KDGKBMODE" },
253 { KDGKBTYPE
, KERN_INFO
, "KDGKBTYPE" },
254 { KDSIGACCEPT
, KERN_INFO
, "KDSIGACCEPT" },
257 int line_ioctl(struct tty_struct
*tty
, struct file
* file
,
258 unsigned int cmd
, unsigned long arg
)
302 for (i
= 0; i
< ARRAY_SIZE(tty_ioctls
); i
++)
303 if (cmd
== tty_ioctls
[i
].cmd
)
305 if (i
== ARRAY_SIZE(tty_ioctls
)) {
306 printk(KERN_ERR
"%s: %s: unknown ioctl: 0x%x\n",
307 __func__
, tty
->name
, cmd
);
315 void line_throttle(struct tty_struct
*tty
)
317 struct line
*line
= tty
->driver_data
;
319 deactivate_chan(&line
->chan_list
, line
->driver
->read_irq
);
323 void line_unthrottle(struct tty_struct
*tty
)
325 struct line
*line
= tty
->driver_data
;
328 chan_interrupt(&line
->chan_list
, &line
->task
, tty
,
329 line
->driver
->read_irq
);
332 * Maybe there is enough stuff pending that calling the interrupt
333 * throttles us again. In this case, line->throttled will be 1
334 * again and we shouldn't turn the interrupt back on.
336 if (!line
->throttled
)
337 reactivate_chan(&line
->chan_list
, line
->driver
->read_irq
);
340 static irqreturn_t
line_write_interrupt(int irq
, void *data
)
342 struct chan
*chan
= data
;
343 struct line
*line
= chan
->line
;
344 struct tty_struct
*tty
= line
->tty
;
348 * Interrupts are disabled here because we registered the interrupt with
349 * IRQF_DISABLED (see line_setup_irq).
352 spin_lock(&line
->lock
);
353 err
= flush_buffer(line
);
356 } else if (err
< 0) {
357 line
->head
= line
->buffer
;
358 line
->tail
= line
->buffer
;
360 spin_unlock(&line
->lock
);
365 if (test_bit(TTY_DO_WRITE_WAKEUP
, &tty
->flags
) &&
366 (tty
->ldisc
.write_wakeup
!= NULL
))
367 (tty
->ldisc
.write_wakeup
)(tty
);
371 * In blocking mode, everything sleeps on tty->write_wait.
372 * Sleeping in the console driver would break non-blocking
376 if (waitqueue_active(&tty
->write_wait
))
377 wake_up_interruptible(&tty
->write_wait
);
381 int line_setup_irq(int fd
, int input
, int output
, struct line
*line
, void *data
)
383 const struct line_driver
*driver
= line
->driver
;
384 int err
= 0, flags
= IRQF_DISABLED
| IRQF_SHARED
| IRQF_SAMPLE_RANDOM
;
387 err
= um_request_irq(driver
->read_irq
, fd
, IRQ_READ
,
388 line_interrupt
, flags
,
389 driver
->read_irq_name
, data
);
393 err
= um_request_irq(driver
->write_irq
, fd
, IRQ_WRITE
,
394 line_write_interrupt
, flags
,
395 driver
->write_irq_name
, data
);
401 * Normally, a driver like this can rely mostly on the tty layer
402 * locking, particularly when it comes to the driver structure.
403 * However, in this case, mconsole requests can come in "from the
404 * side", and race with opens and closes.
406 * mconsole config requests will want to be sure the device isn't in
407 * use, and get_config, open, and close will want a stable
408 * configuration. The checking and modification of the configuration
409 * is done under a spinlock. Checking whether the device is in use is
410 * line->tty->count > 1, also under the spinlock.
412 * tty->count serves to decide whether the device should be enabled or
413 * disabled on the host. If it's equal to 1, then we are doing the
414 * first open or last close. Otherwise, open and close just return.
417 int line_open(struct line
*lines
, struct tty_struct
*tty
)
419 struct line
*line
= &lines
[tty
->index
];
422 spin_lock(&line
->count_lock
);
430 spin_unlock(&line
->count_lock
);
432 tty
->driver_data
= line
;
435 err
= enable_chan(line
);
439 INIT_DELAYED_WORK(&line
->task
, line_timer_cb
);
442 chan_enable_winch(&line
->chan_list
, tty
);
446 chan_window_size(&line
->chan_list
, &tty
->winsize
.ws_row
,
447 &tty
->winsize
.ws_col
);
452 spin_unlock(&line
->count_lock
);
456 static void unregister_winch(struct tty_struct
*tty
);
458 void line_close(struct tty_struct
*tty
, struct file
* filp
)
460 struct line
*line
= tty
->driver_data
;
463 * If line_open fails (and tty->driver_data is never set),
464 * tty_open will call line_close. So just return in this case.
469 /* We ignore the error anyway! */
472 spin_lock(&line
->count_lock
);
479 spin_unlock(&line
->count_lock
);
482 tty
->driver_data
= NULL
;
485 unregister_winch(tty
);
492 spin_unlock(&line
->count_lock
);
495 void close_lines(struct line
*lines
, int nlines
)
499 for(i
= 0; i
< nlines
; i
++)
500 close_chan(&lines
[i
].chan_list
, 0);
503 static int setup_one_line(struct line
*lines
, int n
, char *init
, int init_prio
,
506 struct line
*line
= &lines
[n
];
509 spin_lock(&line
->count_lock
);
511 if (line
->tty
!= NULL
) {
512 *error_out
= "Device is already open";
516 if (line
->init_pri
<= init_prio
) {
517 line
->init_pri
= init_prio
;
518 if (!strcmp(init
, "none"))
521 line
->init_str
= init
;
527 spin_unlock(&line
->count_lock
);
532 * Common setup code for both startup command line and mconsole initialization.
533 * @lines contains the array (of size @num) to modify;
534 * @init is the setup string;
535 * @error_out is an error string in the case of failure;
538 int line_setup(struct line
*lines
, unsigned int num
, char *init
,
546 * We said con=/ssl= instead of con#=, so we are configuring all
552 n
= simple_strtoul(init
, &end
, 0);
554 *error_out
= "Couldn't parse device number";
561 if (n
>= (signed int) num
) {
562 *error_out
= "Device number out of range";
566 err
= setup_one_line(lines
, n
, init
, INIT_ONE
, error_out
);
571 for(i
= 0; i
< num
; i
++) {
572 err
= setup_one_line(lines
, i
, init
, INIT_ALL
,
578 return n
== -1 ? num
: n
;
581 int line_config(struct line
*lines
, unsigned int num
, char *str
,
582 const struct chan_opts
*opts
, char **error_out
)
589 *error_out
= "Can't configure all devices from mconsole";
593 new = kstrdup(str
, GFP_KERNEL
);
595 *error_out
= "Failed to allocate memory";
598 n
= line_setup(lines
, num
, new, error_out
);
603 return parse_chan_pair(line
->init_str
, line
, n
, opts
, error_out
);
606 int line_get_config(char *name
, struct line
*lines
, unsigned int num
, char *str
,
607 int size
, char **error_out
)
613 dev
= simple_strtoul(name
, &end
, 0);
614 if ((*end
!= '\0') || (end
== name
)) {
615 *error_out
= "line_get_config failed to parse device number";
619 if ((dev
< 0) || (dev
>= num
)) {
620 *error_out
= "device number out of range";
626 spin_lock(&line
->count_lock
);
628 CONFIG_CHUNK(str
, size
, n
, "none", 1);
629 else if (line
->tty
== NULL
)
630 CONFIG_CHUNK(str
, size
, n
, line
->init_str
, 1);
631 else n
= chan_config_string(&line
->chan_list
, str
, size
, error_out
);
632 spin_unlock(&line
->count_lock
);
637 int line_id(char **str
, int *start_out
, int *end_out
)
642 n
= simple_strtoul(*str
, &end
, 0);
643 if ((*end
!= '\0') || (end
== *str
))
652 int line_remove(struct line
*lines
, unsigned int num
, int n
, char **error_out
)
655 char config
[sizeof("conxxxx=none\0")];
657 sprintf(config
, "%d=none", n
);
658 err
= line_setup(lines
, num
, config
, error_out
);
664 struct tty_driver
*register_lines(struct line_driver
*line_driver
,
665 const struct tty_operations
*ops
,
666 struct line
*lines
, int nlines
)
669 struct tty_driver
*driver
= alloc_tty_driver(nlines
);
674 driver
->driver_name
= line_driver
->name
;
675 driver
->name
= line_driver
->device_name
;
676 driver
->major
= line_driver
->major
;
677 driver
->minor_start
= line_driver
->minor_start
;
678 driver
->type
= line_driver
->type
;
679 driver
->subtype
= line_driver
->subtype
;
680 driver
->flags
= TTY_DRIVER_REAL_RAW
;
681 driver
->init_termios
= tty_std_termios
;
682 tty_set_operations(driver
, ops
);
684 if (tty_register_driver(driver
)) {
685 printk(KERN_ERR
"register_lines : can't register %s driver\n",
687 put_tty_driver(driver
);
691 for(i
= 0; i
< nlines
; i
++) {
693 tty_unregister_device(driver
, i
);
696 mconsole_register_dev(&line_driver
->mc
);
700 static DEFINE_SPINLOCK(winch_handler_lock
);
701 static LIST_HEAD(winch_handlers
);
703 void lines_init(struct line
*lines
, int nlines
, struct chan_opts
*opts
)
709 for(i
= 0; i
< nlines
; i
++) {
711 INIT_LIST_HEAD(&line
->chan_list
);
713 if (line
->init_str
== NULL
)
716 line
->init_str
= kstrdup(line
->init_str
, GFP_KERNEL
);
717 if (line
->init_str
== NULL
)
718 printk(KERN_ERR
"lines_init - kstrdup returned NULL\n");
720 if (parse_chan_pair(line
->init_str
, line
, i
, opts
, &error
)) {
721 printk(KERN_ERR
"parse_chan_pair failed for "
722 "device %d : %s\n", i
, error
);
729 struct list_head list
;
733 struct tty_struct
*tty
;
737 static void free_winch(struct winch
*winch
, int free_irq_ok
)
739 list_del(&winch
->list
);
741 if (winch
->pid
!= -1)
742 os_kill_process(winch
->pid
, 1);
744 os_close_file(winch
->fd
);
745 if (winch
->stack
!= 0)
746 free_stack(winch
->stack
, 0);
748 free_irq(WINCH_IRQ
, winch
);
752 static irqreturn_t
winch_interrupt(int irq
, void *data
)
754 struct winch
*winch
= data
;
755 struct tty_struct
*tty
;
760 if (winch
->fd
!= -1) {
761 err
= generic_read(winch
->fd
, &c
, NULL
);
763 if (err
!= -EAGAIN
) {
764 printk(KERN_ERR
"winch_interrupt : "
765 "read failed, errno = %d\n", -err
);
766 printk(KERN_ERR
"fd %d is losing SIGWINCH "
767 "support\n", winch
->tty_fd
);
768 free_winch(winch
, 0);
776 line
= tty
->driver_data
;
778 chan_window_size(&line
->chan_list
, &tty
->winsize
.ws_row
,
779 &tty
->winsize
.ws_col
);
780 kill_pgrp(tty
->pgrp
, SIGWINCH
, 1);
785 reactivate_fd(winch
->fd
, WINCH_IRQ
);
789 void register_winch_irq(int fd
, int tty_fd
, int pid
, struct tty_struct
*tty
,
794 winch
= kmalloc(sizeof(*winch
), GFP_KERNEL
);
796 printk(KERN_ERR
"register_winch_irq - kmalloc failed\n");
800 *winch
= ((struct winch
) { .list
= LIST_HEAD_INIT(winch
->list
),
807 if (um_request_irq(WINCH_IRQ
, fd
, IRQ_READ
, winch_interrupt
,
808 IRQF_DISABLED
| IRQF_SHARED
| IRQF_SAMPLE_RANDOM
,
809 "winch", winch
) < 0) {
810 printk(KERN_ERR
"register_winch_irq - failed to register "
815 spin_lock(&winch_handler_lock
);
816 list_add(&winch
->list
, &winch_handlers
);
817 spin_unlock(&winch_handler_lock
);
824 os_kill_process(pid
, 1);
827 free_stack(stack
, 0);
830 static void unregister_winch(struct tty_struct
*tty
)
832 struct list_head
*ele
;
835 spin_lock(&winch_handler_lock
);
837 list_for_each(ele
, &winch_handlers
) {
838 winch
= list_entry(ele
, struct winch
, list
);
839 if (winch
->tty
== tty
) {
840 free_winch(winch
, 1);
844 spin_unlock(&winch_handler_lock
);
847 static void winch_cleanup(void)
849 struct list_head
*ele
, *next
;
852 spin_lock(&winch_handler_lock
);
854 list_for_each_safe(ele
, next
, &winch_handlers
) {
855 winch
= list_entry(ele
, struct winch
, list
);
856 free_winch(winch
, 1);
859 spin_unlock(&winch_handler_lock
);
861 __uml_exitcall(winch_cleanup
);
863 char *add_xterm_umid(char *base
)
872 len
= strlen(base
) + strlen(" ()") + strlen(umid
) + 1;
873 title
= kmalloc(len
, GFP_KERNEL
);
875 printk(KERN_ERR
"Failed to allocate buffer for xterm title\n");
879 snprintf(title
, len
, "%s (%s)", base
, umid
);