You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
185 lines
4.6 KiB
185 lines
4.6 KiB
/*
|
|
* Copyright (c) 2004-2005 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
|
|
*/
|
|
#include "xfs.h"
|
|
#include "xfs_types.h"
|
|
#include "xfs_dmapi.h"
|
|
#include "xfs_log.h"
|
|
#include "xfs_trans.h"
|
|
#include "xfs_sb.h"
|
|
#include "xfs_dir.h"
|
|
#include "xfs_mount.h"
|
|
#include "xfs_export.h"
|
|
|
|
STATIC struct dentry dotdot = { .d_name.name = "..", .d_name.len = 2, };
|
|
|
|
/*
|
|
* XFS encodes and decodes the fileid portion of NFS filehandles
|
|
* itself instead of letting the generic NFS code do it. This
|
|
* allows filesystems with 64 bit inode numbers to be exported.
|
|
*
|
|
* Note that a side effect is that xfs_vget() won't be passed a
|
|
* zero inode/generation pair under normal circumstances. As
|
|
* however a malicious client could send us such data, the check
|
|
* remains in that code.
|
|
*/
|
|
|
|
STATIC struct dentry *
|
|
xfs_fs_decode_fh(
|
|
struct super_block *sb,
|
|
__u32 *fh,
|
|
int fh_len,
|
|
int fileid_type,
|
|
int (*acceptable)(
|
|
void *context,
|
|
struct dentry *de),
|
|
void *context)
|
|
{
|
|
xfs_fid2_t ifid;
|
|
xfs_fid2_t pfid;
|
|
void *parent = NULL;
|
|
int is64 = 0;
|
|
__u32 *p = fh;
|
|
|
|
#if XFS_BIG_INUMS
|
|
is64 = (fileid_type & XFS_FILEID_TYPE_64FLAG);
|
|
fileid_type &= ~XFS_FILEID_TYPE_64FLAG;
|
|
#endif
|
|
|
|
/*
|
|
* Note that we only accept fileids which are long enough
|
|
* rather than allow the parent generation number to default
|
|
* to zero. XFS considers zero a valid generation number not
|
|
* an invalid/wildcard value. There's little point printk'ing
|
|
* a warning here as we don't have the client information
|
|
* which would make such a warning useful.
|
|
*/
|
|
if (fileid_type > 2 ||
|
|
fh_len < xfs_fileid_length((fileid_type == 2), is64))
|
|
return NULL;
|
|
|
|
p = xfs_fileid_decode_fid2(p, &ifid, is64);
|
|
|
|
if (fileid_type == 2) {
|
|
p = xfs_fileid_decode_fid2(p, &pfid, is64);
|
|
parent = &pfid;
|
|
}
|
|
|
|
fh = (__u32 *)&ifid;
|
|
return sb->s_export_op->find_exported_dentry(sb, fh, parent, acceptable, context);
|
|
}
|
|
|
|
|
|
STATIC int
|
|
xfs_fs_encode_fh(
|
|
struct dentry *dentry,
|
|
__u32 *fh,
|
|
int *max_len,
|
|
int connectable)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
int type = 1;
|
|
__u32 *p = fh;
|
|
int len;
|
|
int is64 = 0;
|
|
#if XFS_BIG_INUMS
|
|
vfs_t *vfs = vfs_from_sb(inode->i_sb);
|
|
|
|
if (!(vfs->vfs_flag & VFS_32BITINODES)) {
|
|
/* filesystem may contain 64bit inode numbers */
|
|
is64 = XFS_FILEID_TYPE_64FLAG;
|
|
}
|
|
#endif
|
|
|
|
/* Directories don't need their parent encoded, they have ".." */
|
|
if (S_ISDIR(inode->i_mode))
|
|
connectable = 0;
|
|
|
|
/*
|
|
* Only encode if there is enough space given. In practice
|
|
* this means we can't export a filesystem with 64bit inodes
|
|
* over NFSv2 with the subtree_check export option; the other
|
|
* seven combinations work. The real answer is "don't use v2".
|
|
*/
|
|
len = xfs_fileid_length(connectable, is64);
|
|
if (*max_len < len)
|
|
return 255;
|
|
*max_len = len;
|
|
|
|
p = xfs_fileid_encode_inode(p, inode, is64);
|
|
if (connectable) {
|
|
spin_lock(&dentry->d_lock);
|
|
p = xfs_fileid_encode_inode(p, dentry->d_parent->d_inode, is64);
|
|
spin_unlock(&dentry->d_lock);
|
|
type = 2;
|
|
}
|
|
BUG_ON((p - fh) != len);
|
|
return type | is64;
|
|
}
|
|
|
|
STATIC struct dentry *
|
|
xfs_fs_get_dentry(
|
|
struct super_block *sb,
|
|
void *data)
|
|
{
|
|
vnode_t *vp;
|
|
struct inode *inode;
|
|
struct dentry *result;
|
|
vfs_t *vfsp = vfs_from_sb(sb);
|
|
int error;
|
|
|
|
VFS_VGET(vfsp, &vp, (fid_t *)data, error);
|
|
if (error || vp == NULL)
|
|
return ERR_PTR(-ESTALE) ;
|
|
|
|
inode = vn_to_inode(vp);
|
|
result = d_alloc_anon(inode);
|
|
if (!result) {
|
|
iput(inode);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
STATIC struct dentry *
|
|
xfs_fs_get_parent(
|
|
struct dentry *child)
|
|
{
|
|
int error;
|
|
vnode_t *vp, *cvp;
|
|
struct dentry *parent;
|
|
|
|
cvp = NULL;
|
|
vp = vn_from_inode(child->d_inode);
|
|
VOP_LOOKUP(vp, &dotdot, &cvp, 0, NULL, NULL, error);
|
|
if (unlikely(error))
|
|
return ERR_PTR(-error);
|
|
|
|
parent = d_alloc_anon(vn_to_inode(cvp));
|
|
if (unlikely(!parent)) {
|
|
VN_RELE(cvp);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
return parent;
|
|
}
|
|
|
|
struct export_operations xfs_export_operations = {
|
|
.decode_fh = xfs_fs_decode_fh,
|
|
.encode_fh = xfs_fs_encode_fh,
|
|
.get_parent = xfs_fs_get_parent,
|
|
.get_dentry = xfs_fs_get_dentry,
|
|
};
|
|
|