Re: [PATCH] UBI: add ioctl compatibility

Artem Bityutskiy
2009-01-16T14:33:57Z

On Fri, 2009-01-16 at 13:24 +0100, Arnd Bergmann wrote:
> On Friday 16 January 2009, Artem Bityutskiy wrote:
> > Thank you Arnd. Here is the corrected patch. Tested on x68_64 + 32-bit
> > UBI tools.
> >
>
> Looks better now, but the compat_ versions are still missing the
> compat_ptr() conversions. Those only make a difference on s390,
> so you wouldn't see the problem on x86_64.

Ok, here is the new patch.

From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Subject: [PATCH] UBI: add ioctl compatibility

UBI ioctl's do not work when running 64-bit kernel and 32-bit
user-land. Fix this by adding the compat_ioctl method.

Also, UBI serializes all ioctls, so more than one ioctl at a time
is not a problem. Amd UBI does not seem to depend on anything else,
so use unlocked_ioctl instead of ioctl (no BKL needed).

Reported-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
drivers/mtd/ubi/cdev.c | 66 ++++++++++++++++++++++++++++++++++--------------
1 files changed, 47 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index d99935c..820f50e 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -40,6 +40,7 @@
#include <linux/ioctl.h>
#include <linux/capability.h>
#include <linux/uaccess.h>
+#include <linux/compat.h>
#include <mtd/ubi-user.h>
#include <asm/div64.h>
#include "ubi.h"
@@ -401,8 +402,8 @@ static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
return count;
}

-static int vol_cdev_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static long vol_cdev_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
int err = 0;
struct ubi_volume_desc *desc = file->private_data;
@@ -566,6 +567,14 @@ static int vol_cdev_ioctl(struct inode *inode, struct file *file,
return err;
}

+static long vol_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return vol_cdev_ioctl(file, cmd, translated_arg);
+}
+
/**
* verify_mkvol_req - verify volume creation request.
* @ubi: UBI device description object
@@ -800,8 +809,8 @@ out_free:
return err;
}

-static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static long ubi_cdev_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
int err = 0;
struct ubi_device *ubi;
@@ -811,7 +820,7 @@ static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;

- ubi = ubi_get_by_major(imajor(inode));
+ ubi = ubi_get_by_major(imajor(file->f_mapping->host));
if (!ubi)
return -ENODEV;

@@ -947,8 +956,16 @@ static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
return err;
}

-static int ctrl_cdev_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static long ubi_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return ubi_cdev_ioctl(file, cmd, translated_arg);
+}
+
+static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
int err = 0;
void __user *argp = (void __user *)arg;
@@ -1024,26 +1041,37 @@ static int ctrl_cdev_ioctl(struct inode *inode, struct file *file,
return err;
}

+static long ctrl_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return ctrl_cdev_ioctl(file, cmd, translated_arg);
+}
+
/* UBI control character device operations */
const struct file_operations ubi_ctrl_cdev_operations = {
- .ioctl = ctrl_cdev_ioctl,
- .owner = THIS_MODULE,
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = ctrl_cdev_ioctl,
+ .compat_ioctl = ctrl_cdev_compat_ioctl,
};

/* UBI character device operations */
const struct file_operations ubi_cdev_operations = {
- .owner = THIS_MODULE,
- .ioctl = ubi_cdev_ioctl,
- .llseek = no_llseek,
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .unlocked_ioctl = ubi_cdev_ioctl,
+ .compat_ioctl = ubi_cdev_compat_ioctl,
};

/* UBI volume character device operations */
const struct file_operations ubi_vol_cdev_operations = {
- .owner = THIS_MODULE,
- .open = vol_cdev_open,
- .release = vol_cdev_release,
- .llseek = vol_cdev_llseek,
- .read = vol_cdev_read,
- .write = vol_cdev_write,
- .ioctl = vol_cdev_ioctl,
+ .owner = THIS_MODULE,
+ .open = vol_cdev_open,
+ .release = vol_cdev_release,
+ .llseek = vol_cdev_llseek,
+ .read = vol_cdev_read,
+ .write = vol_cdev_write,
+ .unlocked_ioctl = vol_cdev_ioctl,
+ .compat_ioctl = vol_cdev_compat_ioctl,
};