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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2015, Primary Data, Inc. All rights reserved.
*
* Tao Peng <bergwolf@primarydata.com>
*/
#include <linux/dcache.h>
#include <linux/exportfs.h>
#include <linux/nfs.h>
#include <linux/nfs_fs.h>
#include "internal.h"
#include "nfstrace.h"
#define NFSDBG_FACILITY NFSDBG_VFS
enum {
FILEID_HIGH_OFF = 0, /* inode fileid high */
FILEID_LOW_OFF, /* inode fileid low */
FILE_I_TYPE_OFF, /* inode type */
EMBED_FH_OFF /* embeded server fh */
};
static struct nfs_fh *nfs_exp_embedfh(__u32 *p)
{
return (struct nfs_fh *)(p + EMBED_FH_OFF);
}
/*
* Let's break subtree checking for now... otherwise we'll have to embed parent fh
* but there might not be enough space.
*/
static int
nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
{
struct nfs_fh *server_fh = NFS_FH(inode);
struct nfs_fh *clnt_fh = nfs_exp_embedfh(p);
size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size;
int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size);
dprintk("%s: max fh len %d inode %p parent %p",
__func__, *max_len, inode, parent);
if (*max_len < len) {
dprintk("%s: fh len %d too small, required %d\n",
__func__, *max_len, len);
*max_len = len;
return FILEID_INVALID;
}
p[FILEID_HIGH_OFF] = NFS_FILEID(inode) >> 32;
p[FILEID_LOW_OFF] = NFS_FILEID(inode);
p[FILE_I_TYPE_OFF] = inode->i_mode & S_IFMT;
p[len - 1] = 0; /* Padding */
nfs_copy_fh(clnt_fh, server_fh);
*max_len = len;
dprintk("%s: result fh fileid %llu mode %u size %d\n",
__func__, NFS_FILEID(inode), inode->i_mode, *max_len);
return *max_len;
}
static struct dentry *
nfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct nfs_fattr *fattr = NULL;
struct nfs_fh *server_fh = nfs_exp_embedfh(fid->raw);
size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size;
const struct nfs_rpc_ops *rpc_ops;
struct dentry *dentry;
struct inode *inode;
int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size);
u32 *p = fid->raw;
int ret;
/* NULL translates to ESTALE */
if (fh_len < len || fh_type != len)
return NULL;
fattr = nfs_alloc_fattr_with_label(NFS_SB(sb));
if (fattr == NULL) {
dentry = ERR_PTR(-ENOMEM);
goto out;
}
fattr->fileid = ((u64)p[FILEID_HIGH_OFF] << 32) + p[FILEID_LOW_OFF];
fattr->mode = p[FILE_I_TYPE_OFF];
fattr->valid |= NFS_ATTR_FATTR_FILEID | NFS_ATTR_FATTR_TYPE;
dprintk("%s: fileid %llu mode %d\n", __func__, fattr->fileid, fattr->mode);
inode = nfs_ilookup(sb, fattr, server_fh);
if (inode)
goto out_found;
rpc_ops = NFS_SB(sb)->nfs_client->rpc_ops;
ret = rpc_ops->getattr(NFS_SB(sb), server_fh, fattr, NULL);
if (ret) {
dprintk("%s: getattr failed %d\n", __func__, ret);
trace_nfs_fh_to_dentry(sb, server_fh, fattr->fileid, ret);
dentry = ERR_PTR(ret);
goto out_free_fattr;
}
inode = nfs_fhget(sb, server_fh, fattr);
out_found:
dentry = d_obtain_alias(inode);
out_free_fattr:
nfs_free_fattr(fattr);
out:
return dentry;
}
static struct dentry *
nfs_get_parent(struct dentry *dentry)
{
int ret;
struct inode *inode = d_inode(dentry), *pinode;
struct super_block *sb = inode->i_sb;
struct nfs_server *server = NFS_SB(sb);
struct nfs_fattr *fattr = NULL;
struct dentry *parent;
struct nfs_rpc_ops const *ops = server->nfs_client->rpc_ops;
struct nfs_fh fh;
if (!ops->lookupp)
return ERR_PTR(-EACCES);
fattr = nfs_alloc_fattr_with_label(server);
if (fattr == NULL)
return ERR_PTR(-ENOMEM);
ret = ops->lookupp(inode, &fh, fattr);
if (ret) {
parent = ERR_PTR(ret);
goto out;
}
pinode = nfs_fhget(sb, &fh, fattr);
parent = d_obtain_alias(pinode);
out:
nfs_free_fattr(fattr);
return parent;
}
const struct export_operations nfs_export_ops = {
.encode_fh = nfs_encode_fh,
.fh_to_dentry = nfs_fh_to_dentry,
.get_parent = nfs_get_parent,
.flags = EXPORT_OP_NOWCC |
EXPORT_OP_NOSUBTREECHK |
EXPORT_OP_CLOSE_BEFORE_UNLINK |
EXPORT_OP_REMOTE_FS |
EXPORT_OP_NOATOMIC_ATTR |
EXPORT_OP_FLUSH_ON_CLOSE,
};
|
