Loading...
1/*
2 * Copyright (c) 2004-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_format.h"
20#include "xfs_log_format.h"
21#include "xfs_trans_resv.h"
22#include "xfs_mount.h"
23#include "xfs_da_format.h"
24#include "xfs_da_btree.h"
25#include "xfs_dir2.h"
26#include "xfs_export.h"
27#include "xfs_inode.h"
28#include "xfs_trans.h"
29#include "xfs_inode_item.h"
30#include "xfs_trace.h"
31#include "xfs_icache.h"
32#include "xfs_log.h"
33#include "xfs_pnfs.h"
34
35/*
36 * Note that we only accept fileids which are long enough rather than allow
37 * the parent generation number to default to zero. XFS considers zero a
38 * valid generation number not an invalid/wildcard value.
39 */
40static int xfs_fileid_length(int fileid_type)
41{
42 switch (fileid_type) {
43 case FILEID_INO32_GEN:
44 return 2;
45 case FILEID_INO32_GEN_PARENT:
46 return 4;
47 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
48 return 3;
49 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
50 return 6;
51 }
52 return FILEID_INVALID;
53}
54
55STATIC int
56xfs_fs_encode_fh(
57 struct inode *inode,
58 __u32 *fh,
59 int *max_len,
60 struct inode *parent)
61{
62 struct fid *fid = (struct fid *)fh;
63 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh;
64 int fileid_type;
65 int len;
66
67 /* Directories don't need their parent encoded, they have ".." */
68 if (!parent)
69 fileid_type = FILEID_INO32_GEN;
70 else
71 fileid_type = FILEID_INO32_GEN_PARENT;
72
73 /*
74 * If the the filesystem may contain 64bit inode numbers, we need
75 * to use larger file handles that can represent them.
76 *
77 * While we only allocate inodes that do not fit into 32 bits any
78 * large enough filesystem may contain them, thus the slightly
79 * confusing looking conditional below.
80 */
81 if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS) ||
82 (XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_32BITINODES))
83 fileid_type |= XFS_FILEID_TYPE_64FLAG;
84
85 /*
86 * Only encode if there is enough space given. In practice
87 * this means we can't export a filesystem with 64bit inodes
88 * over NFSv2 with the subtree_check export option; the other
89 * seven combinations work. The real answer is "don't use v2".
90 */
91 len = xfs_fileid_length(fileid_type);
92 if (*max_len < len) {
93 *max_len = len;
94 return FILEID_INVALID;
95 }
96 *max_len = len;
97
98 switch (fileid_type) {
99 case FILEID_INO32_GEN_PARENT:
100 fid->i32.parent_ino = XFS_I(parent)->i_ino;
101 fid->i32.parent_gen = parent->i_generation;
102 /*FALLTHRU*/
103 case FILEID_INO32_GEN:
104 fid->i32.ino = XFS_I(inode)->i_ino;
105 fid->i32.gen = inode->i_generation;
106 break;
107 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
108 fid64->parent_ino = XFS_I(parent)->i_ino;
109 fid64->parent_gen = parent->i_generation;
110 /*FALLTHRU*/
111 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
112 fid64->ino = XFS_I(inode)->i_ino;
113 fid64->gen = inode->i_generation;
114 break;
115 }
116
117 return fileid_type;
118}
119
120STATIC struct inode *
121xfs_nfs_get_inode(
122 struct super_block *sb,
123 u64 ino,
124 u32 generation)
125{
126 xfs_mount_t *mp = XFS_M(sb);
127 xfs_inode_t *ip;
128 int error;
129
130 /*
131 * NFS can sometimes send requests for ino 0. Fail them gracefully.
132 */
133 if (ino == 0)
134 return ERR_PTR(-ESTALE);
135
136 /*
137 * The XFS_IGET_UNTRUSTED means that an invalid inode number is just
138 * fine and not an indication of a corrupted filesystem as clients can
139 * send invalid file handles and we have to handle it gracefully..
140 */
141 error = xfs_iget(mp, NULL, ino, XFS_IGET_UNTRUSTED, 0, &ip);
142 if (error) {
143 /*
144 * EINVAL means the inode cluster doesn't exist anymore.
145 * This implies the filehandle is stale, so we should
146 * translate it here.
147 * We don't use ESTALE directly down the chain to not
148 * confuse applications using bulkstat that expect EINVAL.
149 */
150 if (error == -EINVAL || error == -ENOENT)
151 error = -ESTALE;
152 return ERR_PTR(error);
153 }
154
155 if (VFS_I(ip)->i_generation != generation) {
156 IRELE(ip);
157 return ERR_PTR(-ESTALE);
158 }
159
160 return VFS_I(ip);
161}
162
163STATIC struct dentry *
164xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
165 int fh_len, int fileid_type)
166{
167 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
168 struct inode *inode = NULL;
169
170 if (fh_len < xfs_fileid_length(fileid_type))
171 return NULL;
172
173 switch (fileid_type) {
174 case FILEID_INO32_GEN_PARENT:
175 case FILEID_INO32_GEN:
176 inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen);
177 break;
178 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
179 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
180 inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen);
181 break;
182 }
183
184 return d_obtain_alias(inode);
185}
186
187STATIC struct dentry *
188xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid,
189 int fh_len, int fileid_type)
190{
191 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
192 struct inode *inode = NULL;
193
194 if (fh_len < xfs_fileid_length(fileid_type))
195 return NULL;
196
197 switch (fileid_type) {
198 case FILEID_INO32_GEN_PARENT:
199 inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino,
200 fid->i32.parent_gen);
201 break;
202 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
203 inode = xfs_nfs_get_inode(sb, fid64->parent_ino,
204 fid64->parent_gen);
205 break;
206 }
207
208 return d_obtain_alias(inode);
209}
210
211STATIC struct dentry *
212xfs_fs_get_parent(
213 struct dentry *child)
214{
215 int error;
216 struct xfs_inode *cip;
217
218 error = xfs_lookup(XFS_I(d_inode(child)), &xfs_name_dotdot, &cip, NULL);
219 if (unlikely(error))
220 return ERR_PTR(error);
221
222 return d_obtain_alias(VFS_I(cip));
223}
224
225STATIC int
226xfs_fs_nfs_commit_metadata(
227 struct inode *inode)
228{
229 struct xfs_inode *ip = XFS_I(inode);
230 struct xfs_mount *mp = ip->i_mount;
231 xfs_lsn_t lsn = 0;
232
233 xfs_ilock(ip, XFS_ILOCK_SHARED);
234 if (xfs_ipincount(ip))
235 lsn = ip->i_itemp->ili_last_lsn;
236 xfs_iunlock(ip, XFS_ILOCK_SHARED);
237
238 if (!lsn)
239 return 0;
240 return xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
241}
242
243const struct export_operations xfs_export_operations = {
244 .encode_fh = xfs_fs_encode_fh,
245 .fh_to_dentry = xfs_fs_fh_to_dentry,
246 .fh_to_parent = xfs_fs_fh_to_parent,
247 .get_parent = xfs_fs_get_parent,
248 .commit_metadata = xfs_fs_nfs_commit_metadata,
249#ifdef CONFIG_EXPORTFS_BLOCK_OPS
250 .get_uuid = xfs_fs_get_uuid,
251 .map_blocks = xfs_fs_map_blocks,
252 .commit_blocks = xfs_fs_commit_blocks,
253#endif
254};
1/*
2 * Copyright (c) 2004-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_format.h"
20#include "xfs_log_format.h"
21#include "xfs_trans_resv.h"
22#include "xfs_mount.h"
23#include "xfs_da_format.h"
24#include "xfs_da_btree.h"
25#include "xfs_dir2.h"
26#include "xfs_export.h"
27#include "xfs_inode.h"
28#include "xfs_trans.h"
29#include "xfs_inode_item.h"
30#include "xfs_trace.h"
31#include "xfs_icache.h"
32#include "xfs_log.h"
33#include "xfs_pnfs.h"
34
35/*
36 * Note that we only accept fileids which are long enough rather than allow
37 * the parent generation number to default to zero. XFS considers zero a
38 * valid generation number not an invalid/wildcard value.
39 */
40static int xfs_fileid_length(int fileid_type)
41{
42 switch (fileid_type) {
43 case FILEID_INO32_GEN:
44 return 2;
45 case FILEID_INO32_GEN_PARENT:
46 return 4;
47 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
48 return 3;
49 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
50 return 6;
51 }
52 return FILEID_INVALID;
53}
54
55STATIC int
56xfs_fs_encode_fh(
57 struct inode *inode,
58 __u32 *fh,
59 int *max_len,
60 struct inode *parent)
61{
62 struct fid *fid = (struct fid *)fh;
63 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh;
64 int fileid_type;
65 int len;
66
67 /* Directories don't need their parent encoded, they have ".." */
68 if (!parent)
69 fileid_type = FILEID_INO32_GEN;
70 else
71 fileid_type = FILEID_INO32_GEN_PARENT;
72
73 /*
74 * If the the filesystem may contain 64bit inode numbers, we need
75 * to use larger file handles that can represent them.
76 *
77 * While we only allocate inodes that do not fit into 32 bits any
78 * large enough filesystem may contain them, thus the slightly
79 * confusing looking conditional below.
80 */
81 if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS) ||
82 (XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_32BITINODES))
83 fileid_type |= XFS_FILEID_TYPE_64FLAG;
84
85 /*
86 * Only encode if there is enough space given. In practice
87 * this means we can't export a filesystem with 64bit inodes
88 * over NFSv2 with the subtree_check export option; the other
89 * seven combinations work. The real answer is "don't use v2".
90 */
91 len = xfs_fileid_length(fileid_type);
92 if (*max_len < len) {
93 *max_len = len;
94 return FILEID_INVALID;
95 }
96 *max_len = len;
97
98 switch (fileid_type) {
99 case FILEID_INO32_GEN_PARENT:
100 fid->i32.parent_ino = XFS_I(parent)->i_ino;
101 fid->i32.parent_gen = parent->i_generation;
102 /*FALLTHRU*/
103 case FILEID_INO32_GEN:
104 fid->i32.ino = XFS_I(inode)->i_ino;
105 fid->i32.gen = inode->i_generation;
106 break;
107 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
108 fid64->parent_ino = XFS_I(parent)->i_ino;
109 fid64->parent_gen = parent->i_generation;
110 /*FALLTHRU*/
111 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
112 fid64->ino = XFS_I(inode)->i_ino;
113 fid64->gen = inode->i_generation;
114 break;
115 }
116
117 return fileid_type;
118}
119
120STATIC struct inode *
121xfs_nfs_get_inode(
122 struct super_block *sb,
123 u64 ino,
124 u32 generation)
125 {
126 xfs_mount_t *mp = XFS_M(sb);
127 xfs_inode_t *ip;
128 int error;
129
130 /*
131 * NFS can sometimes send requests for ino 0. Fail them gracefully.
132 */
133 if (ino == 0)
134 return ERR_PTR(-ESTALE);
135
136 /*
137 * The XFS_IGET_UNTRUSTED means that an invalid inode number is just
138 * fine and not an indication of a corrupted filesystem as clients can
139 * send invalid file handles and we have to handle it gracefully..
140 */
141 error = xfs_iget(mp, NULL, ino, XFS_IGET_UNTRUSTED, 0, &ip);
142 if (error) {
143 /*
144 * EINVAL means the inode cluster doesn't exist anymore.
145 * This implies the filehandle is stale, so we should
146 * translate it here.
147 * We don't use ESTALE directly down the chain to not
148 * confuse applications using bulkstat that expect EINVAL.
149 */
150 if (error == -EINVAL || error == -ENOENT)
151 error = -ESTALE;
152 return ERR_PTR(error);
153 }
154
155 if (VFS_I(ip)->i_generation != generation) {
156 IRELE(ip);
157 return ERR_PTR(-ESTALE);
158 }
159
160 return VFS_I(ip);
161}
162
163STATIC struct dentry *
164xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
165 int fh_len, int fileid_type)
166{
167 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
168 struct inode *inode = NULL;
169
170 if (fh_len < xfs_fileid_length(fileid_type))
171 return NULL;
172
173 switch (fileid_type) {
174 case FILEID_INO32_GEN_PARENT:
175 case FILEID_INO32_GEN:
176 inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen);
177 break;
178 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
179 case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
180 inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen);
181 break;
182 }
183
184 return d_obtain_alias(inode);
185}
186
187STATIC struct dentry *
188xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid,
189 int fh_len, int fileid_type)
190{
191 struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
192 struct inode *inode = NULL;
193
194 if (fh_len < xfs_fileid_length(fileid_type))
195 return NULL;
196
197 switch (fileid_type) {
198 case FILEID_INO32_GEN_PARENT:
199 inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino,
200 fid->i32.parent_gen);
201 break;
202 case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
203 inode = xfs_nfs_get_inode(sb, fid64->parent_ino,
204 fid64->parent_gen);
205 break;
206 }
207
208 return d_obtain_alias(inode);
209}
210
211STATIC struct dentry *
212xfs_fs_get_parent(
213 struct dentry *child)
214{
215 int error;
216 struct xfs_inode *cip;
217
218 error = xfs_lookup(XFS_I(d_inode(child)), &xfs_name_dotdot, &cip, NULL);
219 if (unlikely(error))
220 return ERR_PTR(error);
221
222 return d_obtain_alias(VFS_I(cip));
223}
224
225STATIC int
226xfs_fs_nfs_commit_metadata(
227 struct inode *inode)
228{
229 struct xfs_inode *ip = XFS_I(inode);
230 struct xfs_mount *mp = ip->i_mount;
231 xfs_lsn_t lsn = 0;
232
233 xfs_ilock(ip, XFS_ILOCK_SHARED);
234 if (xfs_ipincount(ip))
235 lsn = ip->i_itemp->ili_last_lsn;
236 xfs_iunlock(ip, XFS_ILOCK_SHARED);
237
238 if (!lsn)
239 return 0;
240 return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
241}
242
243const struct export_operations xfs_export_operations = {
244 .encode_fh = xfs_fs_encode_fh,
245 .fh_to_dentry = xfs_fs_fh_to_dentry,
246 .fh_to_parent = xfs_fs_fh_to_parent,
247 .get_parent = xfs_fs_get_parent,
248 .commit_metadata = xfs_fs_nfs_commit_metadata,
249#ifdef CONFIG_EXPORTFS_BLOCK_OPS
250 .get_uuid = xfs_fs_get_uuid,
251 .map_blocks = xfs_fs_map_blocks,
252 .commit_blocks = xfs_fs_commit_blocks,
253#endif
254};