ocfs2: Use compat_ptr in reflink_arguments.

Although we use u64 to pass userspace pointers to the kernel
to avoid compat_ioctl, it doesn't work in some ppc platform.
So wrap them with compat_ptr and add compat_ioctl.

The detailed discussion about compat_ptr can be found in thread
http://lkml.org/lkml/2009/10/27/423.

We indeed met with a bug when testing on ppc(-EFAULT is returned
when using old_path). This patch try to fix this.
I have tested in ppc64(with 32 bit reflink) and x86_64(with i686
reflink), both works.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
This commit is contained in:
Tao Ma 2010-01-27 10:21:52 +08:00 committed by Joel Becker
parent cd34edd8cf
commit 34e6c59af0

View File

@ -7,6 +7,7 @@
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/compat.h>
#define MLOG_MASK_PREFIX ML_INODE
#include <cluster/masklog.h>
@ -181,6 +182,10 @@ long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
#ifdef CONFIG_COMPAT
long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
bool preserve;
struct reflink_arguments args;
struct inode *inode = file->f_path.dentry->d_inode;
switch (cmd) {
case OCFS2_IOC32_GETFLAGS:
cmd = OCFS2_IOC_GETFLAGS;
@ -195,8 +200,15 @@ long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
case OCFS2_IOC_GROUP_EXTEND:
case OCFS2_IOC_GROUP_ADD:
case OCFS2_IOC_GROUP_ADD64:
case OCFS2_IOC_REFLINK:
break;
case OCFS2_IOC_REFLINK:
if (copy_from_user(&args, (struct reflink_arguments *)arg,
sizeof(args)))
return -EFAULT;
preserve = (args.preserve != 0);
return ocfs2_reflink_ioctl(inode, compat_ptr(args.old_path),
compat_ptr(args.new_path), preserve);
default:
return -ENOIOCTLCMD;
}