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Diffstat (limited to 'linux-2.6-xen-sparse/drivers/char/tty_io.c')
-rw-r--r--linux-2.6-xen-sparse/drivers/char/tty_io.c156
1 files changed, 96 insertions, 60 deletions
diff --git a/linux-2.6-xen-sparse/drivers/char/tty_io.c b/linux-2.6-xen-sparse/drivers/char/tty_io.c
index 9a4894bb93..20712bfdf4 100644
--- a/linux-2.6-xen-sparse/drivers/char/tty_io.c
+++ b/linux-2.6-xen-sparse/drivers/char/tty_io.c
@@ -94,6 +94,7 @@
#include <linux/idr.h>
#include <linux/wait.h>
#include <linux/bitops.h>
+#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/system.h>
@@ -154,7 +155,6 @@ static int tty_release(struct inode *, struct file *);
int tty_ioctl(struct inode * inode, struct file * file,
unsigned int cmd, unsigned long arg);
static int tty_fasync(int fd, struct file * filp, int on);
-extern void rs_360_init(void);
static void release_mem(struct tty_struct *tty, int idx);
@@ -253,7 +253,7 @@ static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
static DEFINE_SPINLOCK(tty_ldisc_lock);
static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait);
-static struct tty_ldisc tty_ldiscs[NR_LDISCS]; /* line disc dispatch table */
+static struct tty_ldisc tty_ldiscs[NR_LDISCS]; /* line disc dispatch table */
int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
{
@@ -264,24 +264,35 @@ int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
return -EINVAL;
spin_lock_irqsave(&tty_ldisc_lock, flags);
- if (new_ldisc) {
- tty_ldiscs[disc] = *new_ldisc;
- tty_ldiscs[disc].num = disc;
- tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
- tty_ldiscs[disc].refcount = 0;
- } else {
- if(tty_ldiscs[disc].refcount)
- ret = -EBUSY;
- else
- tty_ldiscs[disc].flags &= ~LDISC_FLAG_DEFINED;
- }
+ tty_ldiscs[disc] = *new_ldisc;
+ tty_ldiscs[disc].num = disc;
+ tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
+ tty_ldiscs[disc].refcount = 0;
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
return ret;
}
-
EXPORT_SYMBOL(tty_register_ldisc);
+int tty_unregister_ldisc(int disc)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ if (disc < N_TTY || disc >= NR_LDISCS)
+ return -EINVAL;
+
+ spin_lock_irqsave(&tty_ldisc_lock, flags);
+ if (tty_ldiscs[disc].refcount)
+ ret = -EBUSY;
+ else
+ tty_ldiscs[disc].flags &= ~LDISC_FLAG_DEFINED;
+ spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(tty_unregister_ldisc);
+
struct tty_ldisc *tty_ldisc_get(int disc)
{
unsigned long flags;
@@ -460,21 +471,19 @@ static void tty_ldisc_enable(struct tty_struct *tty)
static int tty_set_ldisc(struct tty_struct *tty, int ldisc)
{
- int retval = 0;
- struct tty_ldisc o_ldisc;
+ int retval = 0;
+ struct tty_ldisc o_ldisc;
char buf[64];
int work;
unsigned long flags;
struct tty_ldisc *ld;
+ struct tty_struct *o_tty;
if ((ldisc < N_TTY) || (ldisc >= NR_LDISCS))
return -EINVAL;
restart:
- if (tty->ldisc.num == ldisc)
- return 0; /* We are already in the desired discipline */
-
ld = tty_ldisc_get(ldisc);
/* Eduardo Blanco <ejbs@cs.cs.com.uy> */
/* Cyrus Durgin <cider@speakeasy.org> */
@@ -485,45 +494,74 @@ restart:
if (ld == NULL)
return -EINVAL;
- o_ldisc = tty->ldisc;
-
tty_wait_until_sent(tty, 0);
+ if (tty->ldisc.num == ldisc) {
+ tty_ldisc_put(ldisc);
+ return 0;
+ }
+
+ o_ldisc = tty->ldisc;
+ o_tty = tty->link;
+
/*
* Make sure we don't change while someone holds a
* reference to the line discipline. The TTY_LDISC bit
* prevents anyone taking a reference once it is clear.
* We need the lock to avoid racing reference takers.
*/
-
+
spin_lock_irqsave(&tty_ldisc_lock, flags);
- if(tty->ldisc.refcount)
- {
- /* Free the new ldisc we grabbed. Must drop the lock
- first. */
+ if (tty->ldisc.refcount || (o_tty && o_tty->ldisc.refcount)) {
+ if(tty->ldisc.refcount) {
+ /* Free the new ldisc we grabbed. Must drop the lock
+ first. */
+ spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+ tty_ldisc_put(ldisc);
+ /*
+ * There are several reasons we may be busy, including
+ * random momentary I/O traffic. We must therefore
+ * retry. We could distinguish between blocking ops
+ * and retries if we made tty_ldisc_wait() smarter. That
+ * is up for discussion.
+ */
+ if (wait_event_interruptible(tty_ldisc_wait, tty->ldisc.refcount == 0) < 0)
+ return -ERESTARTSYS;
+ goto restart;
+ }
+ if(o_tty && o_tty->ldisc.refcount) {
+ spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+ tty_ldisc_put(ldisc);
+ if (wait_event_interruptible(tty_ldisc_wait, o_tty->ldisc.refcount == 0) < 0)
+ return -ERESTARTSYS;
+ goto restart;
+ }
+ }
+
+ /* if the TTY_LDISC bit is set, then we are racing against another ldisc change */
+
+ if (!test_bit(TTY_LDISC, &tty->flags)) {
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
tty_ldisc_put(ldisc);
- /*
- * There are several reasons we may be busy, including
- * random momentary I/O traffic. We must therefore
- * retry. We could distinguish between blocking ops
- * and retries if we made tty_ldisc_wait() smarter. That
- * is up for discussion.
- */
- if(wait_event_interruptible(tty_ldisc_wait, tty->ldisc.refcount == 0) < 0)
- return -ERESTARTSYS;
+ ld = tty_ldisc_ref_wait(tty);
+ tty_ldisc_deref(ld);
goto restart;
}
- clear_bit(TTY_LDISC, &tty->flags);
+
+ clear_bit(TTY_LDISC, &tty->flags);
clear_bit(TTY_DONT_FLIP, &tty->flags);
+ if (o_tty) {
+ clear_bit(TTY_LDISC, &o_tty->flags);
+ clear_bit(TTY_DONT_FLIP, &o_tty->flags);
+ }
spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-
+
/*
* From this point on we know nobody has an ldisc
* usage reference, nor can they obtain one until
* we say so later on.
*/
-
+
work = cancel_delayed_work(&tty->flip.work);
/*
* Wait for ->hangup_work and ->flip.work handlers to terminate
@@ -574,10 +612,12 @@ restart:
*/
tty_ldisc_enable(tty);
+ if (o_tty)
+ tty_ldisc_enable(o_tty);
/* Restart it in case no characters kick it off. Safe if
already running */
- if(work)
+ if (work)
schedule_delayed_work(&tty->flip.work, 1);
return retval;
}
@@ -2171,12 +2211,11 @@ static int tiocsetd(struct tty_struct *tty, int __user *p)
return tty_set_ldisc(tty, ldisc);
}
-static int send_break(struct tty_struct *tty, int duration)
+static int send_break(struct tty_struct *tty, unsigned int duration)
{
tty->driver->break_ctl(tty, -1);
if (!signal_pending(current)) {
- set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(duration);
+ msleep_interruptible(duration);
}
tty->driver->break_ctl(tty, 0);
if (signal_pending(current))
@@ -2357,10 +2396,10 @@ int tty_ioctl(struct inode * inode, struct file * file,
* all by anyone?
*/
if (!arg)
- return send_break(tty, HZ/4);
+ return send_break(tty, 250);
return 0;
case TCSBRKP: /* support for POSIX tcsendbreak() */
- return send_break(tty, arg ? arg*(HZ/10) : HZ/4);
+ return send_break(tty, arg ? arg*100 : 250);
case TIOCMGET:
return tty_tiocmget(tty, file, p);
@@ -2417,6 +2456,7 @@ static void __do_SAK(void *arg)
int i;
struct file *filp;
struct tty_ldisc *disc;
+ struct fdtable *fdt;
if (!tty)
return;
@@ -2442,8 +2482,9 @@ static void __do_SAK(void *arg)
}
task_lock(p);
if (p->files) {
- spin_lock(&p->files->file_lock);
- for (i=0; i < p->files->max_fds; i++) {
+ rcu_read_lock();
+ fdt = files_fdtable(p->files);
+ for (i=0; i < fdt->max_fds; i++) {
filp = fcheck_files(p->files, i);
if (!filp)
continue;
@@ -2456,7 +2497,7 @@ static void __do_SAK(void *arg)
break;
}
}
- spin_unlock(&p->files->file_lock);
+ rcu_read_unlock();
}
task_unlock(p);
} while_each_task_pid(session, PIDTYPE_SID, p);
@@ -2656,7 +2697,7 @@ static void tty_default_put_char(struct tty_struct *tty, unsigned char ch)
tty->driver->write(tty, &ch, 1);
}
-static struct class_simple *tty_class;
+static struct class *tty_class;
/**
* tty_register_device - register a tty device
@@ -2689,7 +2730,7 @@ void tty_register_device(struct tty_driver *driver, unsigned index,
pty_line_name(driver, index, name);
else
tty_line_name(driver, index, name);
- class_simple_device_add(tty_class, dev, device, name);
+ class_device_create(tty_class, dev, device, name);
}
/**
@@ -2703,7 +2744,7 @@ void tty_register_device(struct tty_driver *driver, unsigned index,
void tty_unregister_device(struct tty_driver *driver, unsigned index)
{
devfs_remove("%s%d", driver->devfs_name, index + driver->name_base);
- class_simple_device_remove(MKDEV(driver->major, driver->minor_start) + index);
+ class_device_destroy(tty_class, MKDEV(driver->major, driver->minor_start) + index);
}
EXPORT_SYMBOL(tty_register_device);
@@ -2902,11 +2943,6 @@ void __init console_init(void)
#ifdef CONFIG_EARLY_PRINTK
disable_early_printk();
#endif
-#ifdef CONFIG_SERIAL_68360
- /* This is not a console initcall. I know not what it's doing here.
- So I haven't moved it. dwmw2 */
- rs_360_init();
-#endif
call = __con_initcall_start;
while (call < __con_initcall_end) {
(*call)();
@@ -2920,7 +2956,7 @@ extern int vty_init(void);
static int __init tty_class_init(void)
{
- tty_class = class_simple_create(THIS_MODULE, "tty");
+ tty_class = class_create(THIS_MODULE, "tty");
if (IS_ERR(tty_class))
return PTR_ERR(tty_class);
return 0;
@@ -2949,14 +2985,14 @@ static int __init tty_init(void)
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0)
panic("Couldn't register /dev/tty driver\n");
devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 0), S_IFCHR|S_IRUGO|S_IWUGO, "tty");
- class_simple_device_add(tty_class, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty");
+ class_device_create(tty_class, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty");
cdev_init(&console_cdev, &console_fops);
if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0)
panic("Couldn't register /dev/console driver\n");
devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 1), S_IFCHR|S_IRUSR|S_IWUSR, "console");
- class_simple_device_add(tty_class, MKDEV(TTYAUX_MAJOR, 1), NULL, "console");
+ class_device_create(tty_class, MKDEV(TTYAUX_MAJOR, 1), NULL, "console");
#ifdef CONFIG_UNIX98_PTYS
cdev_init(&ptmx_cdev, &ptmx_fops);
@@ -2964,7 +3000,7 @@ static int __init tty_init(void)
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
panic("Couldn't register /dev/ptmx driver\n");
devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 2), S_IFCHR|S_IRUGO|S_IWUGO, "ptmx");
- class_simple_device_add(tty_class, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
+ class_device_create(tty_class, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
#endif
#ifdef CONFIG_VT
@@ -2975,7 +3011,7 @@ static int __init tty_init(void)
register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
panic("Couldn't register /dev/tty0 driver\n");
devfs_mk_cdev(MKDEV(TTY_MAJOR, 0), S_IFCHR|S_IRUSR|S_IWUSR, "vc/0");
- class_simple_device_add(tty_class, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
+ class_device_create(tty_class, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
vty_init();
out_vt:
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-29 13:09:09 +0000