diff options
Diffstat (limited to 'fs/xfs/xfs_export.c')
-rw-r--r-- | fs/xfs/xfs_export.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c new file mode 100644 index 000000000000..75e5d322e48f --- /dev/null +++ b/fs/xfs/xfs_export.c | |||
@@ -0,0 +1,250 @@ | |||
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_types.h" | ||
20 | #include "xfs_inum.h" | ||
21 | #include "xfs_log.h" | ||
22 | #include "xfs_trans.h" | ||
23 | #include "xfs_sb.h" | ||
24 | #include "xfs_ag.h" | ||
25 | #include "xfs_dir2.h" | ||
26 | #include "xfs_mount.h" | ||
27 | #include "xfs_export.h" | ||
28 | #include "xfs_vnodeops.h" | ||
29 | #include "xfs_bmap_btree.h" | ||
30 | #include "xfs_inode.h" | ||
31 | #include "xfs_inode_item.h" | ||
32 | #include "xfs_trace.h" | ||
33 | |||
34 | /* | ||
35 | * Note that we only accept fileids which are long enough rather than allow | ||
36 | * the parent generation number to default to zero. XFS considers zero a | ||
37 | * valid generation number not an invalid/wildcard value. | ||
38 | */ | ||
39 | static int xfs_fileid_length(int fileid_type) | ||
40 | { | ||
41 | switch (fileid_type) { | ||
42 | case FILEID_INO32_GEN: | ||
43 | return 2; | ||
44 | case FILEID_INO32_GEN_PARENT: | ||
45 | return 4; | ||
46 | case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: | ||
47 | return 3; | ||
48 | case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: | ||
49 | return 6; | ||
50 | } | ||
51 | return 255; /* invalid */ | ||
52 | } | ||
53 | |||
54 | STATIC int | ||
55 | xfs_fs_encode_fh( | ||
56 | struct dentry *dentry, | ||
57 | __u32 *fh, | ||
58 | int *max_len, | ||
59 | int connectable) | ||
60 | { | ||
61 | struct fid *fid = (struct fid *)fh; | ||
62 | struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh; | ||
63 | struct inode *inode = dentry->d_inode; | ||
64 | int fileid_type; | ||
65 | int len; | ||
66 | |||
67 | /* Directories don't need their parent encoded, they have ".." */ | ||
68 | if (S_ISDIR(inode->i_mode) || !connectable) | ||
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 255; | ||
95 | } | ||
96 | *max_len = len; | ||
97 | |||
98 | switch (fileid_type) { | ||
99 | case FILEID_INO32_GEN_PARENT: | ||
100 | spin_lock(&dentry->d_lock); | ||
101 | fid->i32.parent_ino = dentry->d_parent->d_inode->i_ino; | ||
102 | fid->i32.parent_gen = dentry->d_parent->d_inode->i_generation; | ||
103 | spin_unlock(&dentry->d_lock); | ||
104 | /*FALLTHRU*/ | ||
105 | case FILEID_INO32_GEN: | ||
106 | fid->i32.ino = inode->i_ino; | ||
107 | fid->i32.gen = inode->i_generation; | ||
108 | break; | ||
109 | case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: | ||
110 | spin_lock(&dentry->d_lock); | ||
111 | fid64->parent_ino = dentry->d_parent->d_inode->i_ino; | ||
112 | fid64->parent_gen = dentry->d_parent->d_inode->i_generation; | ||
113 | spin_unlock(&dentry->d_lock); | ||
114 | /*FALLTHRU*/ | ||
115 | case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: | ||
116 | fid64->ino = inode->i_ino; | ||
117 | fid64->gen = inode->i_generation; | ||
118 | break; | ||
119 | } | ||
120 | |||
121 | return fileid_type; | ||
122 | } | ||
123 | |||
124 | STATIC struct inode * | ||
125 | xfs_nfs_get_inode( | ||
126 | struct super_block *sb, | ||
127 | u64 ino, | ||
128 | u32 generation) | ||
129 | { | ||
130 | xfs_mount_t *mp = XFS_M(sb); | ||
131 | xfs_inode_t *ip; | ||
132 | int error; | ||
133 | |||
134 | /* | ||
135 | * NFS can sometimes send requests for ino 0. Fail them gracefully. | ||
136 | */ | ||
137 | if (ino == 0) | ||
138 | return ERR_PTR(-ESTALE); | ||
139 | |||
140 | /* | ||
141 | * The XFS_IGET_UNTRUSTED means that an invalid inode number is just | ||
142 | * fine and not an indication of a corrupted filesystem as clients can | ||
143 | * send invalid file handles and we have to handle it gracefully.. | ||
144 | */ | ||
145 | error = xfs_iget(mp, NULL, ino, XFS_IGET_UNTRUSTED, 0, &ip); | ||
146 | if (error) { | ||
147 | /* | ||
148 | * EINVAL means the inode cluster doesn't exist anymore. | ||
149 | * This implies the filehandle is stale, so we should | ||
150 | * translate it here. | ||
151 | * We don't use ESTALE directly down the chain to not | ||
152 | * confuse applications using bulkstat that expect EINVAL. | ||
153 | */ | ||
154 | if (error == EINVAL || error == ENOENT) | ||
155 | error = ESTALE; | ||
156 | return ERR_PTR(-error); | ||
157 | } | ||
158 | |||
159 | if (ip->i_d.di_gen != generation) { | ||
160 | IRELE(ip); | ||
161 | return ERR_PTR(-ESTALE); | ||
162 | } | ||
163 | |||
164 | return VFS_I(ip); | ||
165 | } | ||
166 | |||
167 | STATIC struct dentry * | ||
168 | xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid, | ||
169 | int fh_len, int fileid_type) | ||
170 | { | ||
171 | struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid; | ||
172 | struct inode *inode = NULL; | ||
173 | |||
174 | if (fh_len < xfs_fileid_length(fileid_type)) | ||
175 | return NULL; | ||
176 | |||
177 | switch (fileid_type) { | ||
178 | case FILEID_INO32_GEN_PARENT: | ||
179 | case FILEID_INO32_GEN: | ||
180 | inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen); | ||
181 | break; | ||
182 | case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: | ||
183 | case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: | ||
184 | inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen); | ||
185 | break; | ||
186 | } | ||
187 | |||
188 | return d_obtain_alias(inode); | ||
189 | } | ||
190 | |||
191 | STATIC struct dentry * | ||
192 | xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid, | ||
193 | int fh_len, int fileid_type) | ||
194 | { | ||
195 | struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid; | ||
196 | struct inode *inode = NULL; | ||
197 | |||
198 | switch (fileid_type) { | ||
199 | case FILEID_INO32_GEN_PARENT: | ||
200 | inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino, | ||
201 | fid->i32.parent_gen); | ||
202 | break; | ||
203 | case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: | ||
204 | inode = xfs_nfs_get_inode(sb, fid64->parent_ino, | ||
205 | fid64->parent_gen); | ||
206 | break; | ||
207 | } | ||
208 | |||
209 | return d_obtain_alias(inode); | ||
210 | } | ||
211 | |||
212 | STATIC struct dentry * | ||
213 | xfs_fs_get_parent( | ||
214 | struct dentry *child) | ||
215 | { | ||
216 | int error; | ||
217 | struct xfs_inode *cip; | ||
218 | |||
219 | error = xfs_lookup(XFS_I(child->d_inode), &xfs_name_dotdot, &cip, NULL); | ||
220 | if (unlikely(error)) | ||
221 | return ERR_PTR(-error); | ||
222 | |||
223 | return d_obtain_alias(VFS_I(cip)); | ||
224 | } | ||
225 | |||
226 | STATIC int | ||
227 | xfs_fs_nfs_commit_metadata( | ||
228 | struct inode *inode) | ||
229 | { | ||
230 | struct xfs_inode *ip = XFS_I(inode); | ||
231 | struct xfs_mount *mp = ip->i_mount; | ||
232 | int error = 0; | ||
233 | |||
234 | xfs_ilock(ip, XFS_ILOCK_SHARED); | ||
235 | if (xfs_ipincount(ip)) { | ||
236 | error = _xfs_log_force_lsn(mp, ip->i_itemp->ili_last_lsn, | ||
237 | XFS_LOG_SYNC, NULL); | ||
238 | } | ||
239 | xfs_iunlock(ip, XFS_ILOCK_SHARED); | ||
240 | |||
241 | return error; | ||
242 | } | ||
243 | |||
244 | const struct export_operations xfs_export_operations = { | ||
245 | .encode_fh = xfs_fs_encode_fh, | ||
246 | .fh_to_dentry = xfs_fs_fh_to_dentry, | ||
247 | .fh_to_parent = xfs_fs_fh_to_parent, | ||
248 | .get_parent = xfs_fs_get_parent, | ||
249 | .commit_metadata = xfs_fs_nfs_commit_metadata, | ||
250 | }; | ||