1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/*
* 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_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_export.h"
#include "xfs_vnodeops.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_vfsops.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_fid_t ifid;
xfs_fid_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
if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS)) {
/* 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)
{
bhv_vnode_t *vp;
struct inode *inode;
struct dentry *result;
int error;
error = xfs_vget(XFS_M(sb), &vp, data);
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;
bhv_vnode_t *cvp;
struct dentry *parent;
cvp = NULL;
error = xfs_lookup(XFS_I(child->d_inode), &dotdot, &cvp);
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,
};
|
