android_kernel_xiaomi_sm8350/fs/xfs/linux-2.6/xfs_ioctl.h
Christoph Hellwig ab596ad897 xfs: fix dentry aliasing issues in open_by_handle
Open by handle just grabs an inode by handle and then creates itself
a dentry for it.  While this works for regular files it is horribly
broken for directories, where the VFS locking relies on the fact that
there is only just one single dentry for a given inode, and that
these are always connected to the root of the filesystem so that
it's locking algorithms work (see Documentations/filesystems/Locking)

Remove all the existing open by handle code and replace it with a small
wrapper around the exportfs code which deals with all these issues.
At the same time we also make the checks for a valid handle strict
enough to reject all not perfectly well formed handles - given that
we never hand out others that's okay and simplifies the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2009-01-19 14:43:18 +11:00

86 lines
1.8 KiB
C

/*
* Copyright (c) 2008 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_IOCTL_H__
#define __XFS_IOCTL_H__
extern int
xfs_ioc_space(
struct xfs_inode *ip,
struct inode *inode,
struct file *filp,
int ioflags,
unsigned int cmd,
xfs_flock64_t *bf);
extern int
xfs_find_handle(
unsigned int cmd,
xfs_fsop_handlereq_t *hreq);
extern int
xfs_open_by_handle(
struct file *parfilp,
xfs_fsop_handlereq_t *hreq);
extern int
xfs_readlink_by_handle(
struct file *parfilp,
xfs_fsop_handlereq_t *hreq);
extern int
xfs_attrmulti_attr_get(
struct inode *inode,
char *name,
char __user *ubuf,
__uint32_t *len,
__uint32_t flags);
extern int
xfs_attrmulti_attr_set(
struct inode *inode,
char *name,
const char __user *ubuf,
__uint32_t len,
__uint32_t flags);
extern int
xfs_attrmulti_attr_remove(
struct inode *inode,
char *name,
__uint32_t flags);
extern struct dentry *
xfs_handle_to_dentry(
struct file *parfilp,
void __user *uhandle,
u32 hlen);
extern long
xfs_file_ioctl(
struct file *filp,
unsigned int cmd,
unsigned long p);
extern long
xfs_file_compat_ioctl(
struct file *file,
unsigned int cmd,
unsigned long arg);
#endif