tty: add compat_ioctl
Add compat_ioctl method for tty code to allow processing of 32 bit ioctl
calls on 64 bit systems by tty core, tty drivers, and line disciplines.
Based on patch by Arnd Bergmann:
http://www.uwsg.iu.edu/hypermail/linux/kernel/0511.0/1732.html
[akpm@linux-foundation.org: make things static]
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index fc662e4..fe62c21 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -151,6 +151,12 @@
static int tty_release(struct inode *, struct file *);
int tty_ioctl(struct inode * inode, struct file * file,
unsigned int cmd, unsigned long arg);
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file * file, unsigned int cmd,
+ unsigned long arg);
+#else
+#define tty_compat_ioctl NULL
+#endif
static int tty_fasync(int fd, struct file * filp, int on);
static void release_tty(struct tty_struct *tty, int idx);
static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty);
@@ -1143,8 +1149,8 @@
return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM;
}
-static int hung_up_tty_ioctl(struct inode * inode, struct file * file,
- unsigned int cmd, unsigned long arg)
+static long hung_up_tty_ioctl(struct file * file,
+ unsigned int cmd, unsigned long arg)
{
return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
}
@@ -1155,6 +1161,7 @@
.write = tty_write,
.poll = tty_poll,
.ioctl = tty_ioctl,
+ .compat_ioctl = tty_compat_ioctl,
.open = tty_open,
.release = tty_release,
.fasync = tty_fasync,
@@ -1167,6 +1174,7 @@
.write = tty_write,
.poll = tty_poll,
.ioctl = tty_ioctl,
+ .compat_ioctl = tty_compat_ioctl,
.open = ptmx_open,
.release = tty_release,
.fasync = tty_fasync,
@@ -1179,6 +1187,7 @@
.write = redirected_tty_write,
.poll = tty_poll,
.ioctl = tty_ioctl,
+ .compat_ioctl = tty_compat_ioctl,
.open = tty_open,
.release = tty_release,
.fasync = tty_fasync,
@@ -1189,7 +1198,8 @@
.read = hung_up_tty_read,
.write = hung_up_tty_write,
.poll = hung_up_tty_poll,
- .ioctl = hung_up_tty_ioctl,
+ .unlocked_ioctl = hung_up_tty_ioctl,
+ .compat_ioctl = hung_up_tty_ioctl,
.release = tty_release,
};
@@ -3357,6 +3367,32 @@
return retval;
}
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file * file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ struct tty_struct *tty = file->private_data;
+ struct tty_ldisc *ld;
+ int retval = -ENOIOCTLCMD;
+
+ if (tty_paranoia_check(tty, inode, "tty_ioctl"))
+ return -EINVAL;
+
+ if (tty->driver->compat_ioctl) {
+ retval = (tty->driver->compat_ioctl)(tty, file, cmd, arg);
+ if (retval != -ENOIOCTLCMD)
+ return retval;
+ }
+
+ ld = tty_ldisc_ref_wait(tty);
+ if (ld->compat_ioctl)
+ retval = ld->compat_ioctl(tty, file, cmd, arg);
+ tty_ldisc_deref(ld);
+
+ return retval;
+}
+#endif
/*
* This implements the "Secure Attention Key" --- the idea is to
@@ -3689,6 +3725,7 @@
driver->write_room = op->write_room;
driver->chars_in_buffer = op->chars_in_buffer;
driver->ioctl = op->ioctl;
+ driver->compat_ioctl = op->compat_ioctl;
driver->set_termios = op->set_termios;
driver->throttle = op->throttle;
driver->unthrottle = op->unthrottle;