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tty: Remove more special casing and out of place code

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Carry on pushing code out of tty_io when it belongs to other drivers. I'm
not 100% happy with some of this and it will be worth revisiting some of the
exports later when the restructuring work is done.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alan Cox
2008-10-13 10:41:42 +01:00
committed by Linus Torvalds
parent feebed6515
commit d81ed10307
6 changed files with 195 additions and 156 deletions
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78
drivers/char/pty.c
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@@ -23,6 +23,7 @@
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/sysctl.h>
#include <linux/device.h>
#include <asm/uaccess.h>
#include <asm/system.h>
@@ -332,6 +333,8 @@ int pty_limit = NR_UNIX98_PTY_DEFAULT;
static int pty_limit_min = 0;
static int pty_limit_max = NR_UNIX98_PTY_MAX;
static struct cdev ptmx_cdev;
static struct ctl_table pty_table[] = {
{
.ctl_name = PTY_MAX,
@@ -408,6 +411,70 @@ static const struct tty_operations ptm_unix98_ops = {
.shutdown = pty_shutdown
};
/**
* ptmx_open - open a unix 98 pty master
* @inode: inode of device file
* @filp: file pointer to tty
*
* Allocate a unix98 pty master device from the ptmx driver.
*
* Locking: tty_mutex protects the init_dev work. tty->count should
* protect the rest.
* allocated_ptys_lock handles the list of free pty numbers
*/
static int __ptmx_open(struct inode *inode, struct file *filp)
{
struct tty_struct *tty;
int retval;
int index;
nonseekable_open(inode, filp);
/* find a device that is not in use. */
index = devpts_new_index();
if (index < 0)
return index;
mutex_lock(&tty_mutex);
retval = tty_init_dev(ptm_driver, index, &tty, 1);
mutex_unlock(&tty_mutex);
if (retval)
goto out;
set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
filp->private_data = tty;
file_move(filp, &tty->tty_files);
retval = devpts_pty_new(tty->link);
if (retval)
goto out1;
retval = ptm_driver->ops->open(tty, filp);
if (!retval)
return 0;
out1:
tty_release_dev(filp);
return retval;
out:
devpts_kill_index(index);
return retval;
}
static int ptmx_open(struct inode *inode, struct file *filp)
{
int ret;
lock_kernel();
ret = __ptmx_open(inode, filp);
unlock_kernel();
return ret;
}
static struct file_operations ptmx_fops;
static void __init unix98_pty_init(void)
{
ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
@@ -459,7 +526,18 @@ static void __init unix98_pty_init(void)
pty_table[1].data = &ptm_driver->refcount;
register_sysctl_table(pty_root_table);
/* Now create the /dev/ptmx special device */
tty_default_fops(&ptmx_fops);
ptmx_fops.open = ptmx_open;
cdev_init(&ptmx_cdev, &ptmx_fops);
if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
panic("Couldn't register /dev/ptmx driver\n");
device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
}
#else
static inline void unix98_pty_init(void) { }
#endif