static int tty_ldiscs_seq_show(struct seq_file *m, void *v)
{
int i = *(loff_t *)v;
struct tty_ldisc_ops *ldops;
ldops = get_ldops(i);
if (IS_ERR(ldops))
return 0;
seq_printf(m, "%-10s %2d\n", ldops->name ? ldops->name : "???", i);
put_ldops(ldops);
return 0;
}
/**
* tty_ldisc_get - Take a reference of a line discipine
* @tty: the tty in move
* @disc: disc number
*
* Takes a reference of a line discipline op, deals with refcount.
* Returns %NULL if line discipline op is not available. Return the
* pointer to the tty_ldisc if succeed, and increases the refcount
* of the line discipline op.
*/
static struct tty_ldisc *tty_ldisc_get(struct tty_struct *tty, int disc)
{
struct tty_ldisc *ld;
struct tty_ldisc_ops *ldops;
if (disc < N_TTY || disc >= NR_LDISCS)
return ERR_PTR(-EINVAL);
ldops = get_ldops(disc);
if (IS_ERR(ldops))
return ERR_CAST(ldops);
ld = kmalloc(sizeof(struct tty_ldisc), 1);
if (!ld) {
put_ldops(ldops);
return ERR_PTR(-ENOMEM);
}
ld->ops = ldops;
ld->tty = tty;
return ld;
}