1 /*
2 * Copyright (c) 2000-2003,2005 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_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_log.h"
22 #include "xfs_inum.h"
23 #include "xfs_trans.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_dir2.h"
27 #include "xfs_mount.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_dinode.h"
31 #include "xfs_inode.h"
32 #include "xfs_inode_item.h"
33 #include "xfs_bmap.h"
34 #include "xfs_error.h"
35 #include "xfs_quota.h"
36 #include "xfs_utils.h"
37 #include "xfs_trans_space.h"
38 #include "xfs_vnodeops.h"
39 #include "xfs_trace.h"
40
41
42 /*
43 * Enter all inodes for a rename transaction into a sorted array.
44 */
45 STATIC void
xfs_sort_for_rename(xfs_inode_t * dp1,xfs_inode_t * dp2,xfs_inode_t * ip1,xfs_inode_t * ip2,xfs_inode_t ** i_tab,int * num_inodes)46 xfs_sort_for_rename(
47 xfs_inode_t *dp1, /* in: old (source) directory inode */
48 xfs_inode_t *dp2, /* in: new (target) directory inode */
49 xfs_inode_t *ip1, /* in: inode of old entry */
50 xfs_inode_t *ip2, /* in: inode of new entry, if it
51 already exists, NULL otherwise. */
52 xfs_inode_t **i_tab,/* out: array of inode returned, sorted */
53 int *num_inodes) /* out: number of inodes in array */
54 {
55 xfs_inode_t *temp;
56 int i, j;
57
58 /*
59 * i_tab contains a list of pointers to inodes. We initialize
60 * the table here & we'll sort it. We will then use it to
61 * order the acquisition of the inode locks.
62 *
63 * Note that the table may contain duplicates. e.g., dp1 == dp2.
64 */
65 i_tab[0] = dp1;
66 i_tab[1] = dp2;
67 i_tab[2] = ip1;
68 if (ip2) {
69 *num_inodes = 4;
70 i_tab[3] = ip2;
71 } else {
72 *num_inodes = 3;
73 i_tab[3] = NULL;
74 }
75
76 /*
77 * Sort the elements via bubble sort. (Remember, there are at
78 * most 4 elements to sort, so this is adequate.)
79 */
80 for (i = 0; i < *num_inodes; i++) {
81 for (j = 1; j < *num_inodes; j++) {
82 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
83 temp = i_tab[j];
84 i_tab[j] = i_tab[j-1];
85 i_tab[j-1] = temp;
86 }
87 }
88 }
89 }
90
91 /*
92 * xfs_rename
93 */
94 int
xfs_rename(xfs_inode_t * src_dp,struct xfs_name * src_name,xfs_inode_t * src_ip,xfs_inode_t * target_dp,struct xfs_name * target_name,xfs_inode_t * target_ip)95 xfs_rename(
96 xfs_inode_t *src_dp,
97 struct xfs_name *src_name,
98 xfs_inode_t *src_ip,
99 xfs_inode_t *target_dp,
100 struct xfs_name *target_name,
101 xfs_inode_t *target_ip)
102 {
103 xfs_trans_t *tp = NULL;
104 xfs_mount_t *mp = src_dp->i_mount;
105 int new_parent; /* moving to a new dir */
106 int src_is_directory; /* src_name is a directory */
107 int error;
108 xfs_bmap_free_t free_list;
109 xfs_fsblock_t first_block;
110 int cancel_flags;
111 int committed;
112 xfs_inode_t *inodes[4];
113 int spaceres;
114 int num_inodes;
115
116 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
117
118 new_parent = (src_dp != target_dp);
119 src_is_directory = S_ISDIR(src_ip->i_d.di_mode);
120
121 if (src_is_directory) {
122 /*
123 * Check for link count overflow on target_dp
124 */
125 if (target_ip == NULL && new_parent &&
126 target_dp->i_d.di_nlink >= XFS_MAXLINK) {
127 error = XFS_ERROR(EMLINK);
128 goto std_return;
129 }
130 }
131
132 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
133 inodes, &num_inodes);
134
135 xfs_bmap_init(&free_list, &first_block);
136 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
137 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
138 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
139 error = xfs_trans_reserve(tp, spaceres, XFS_RENAME_LOG_RES(mp), 0,
140 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
141 if (error == ENOSPC) {
142 spaceres = 0;
143 error = xfs_trans_reserve(tp, 0, XFS_RENAME_LOG_RES(mp), 0,
144 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
145 }
146 if (error) {
147 xfs_trans_cancel(tp, 0);
148 goto std_return;
149 }
150
151 /*
152 * Attach the dquots to the inodes
153 */
154 error = xfs_qm_vop_rename_dqattach(inodes);
155 if (error) {
156 xfs_trans_cancel(tp, cancel_flags);
157 goto std_return;
158 }
159
160 /*
161 * Lock all the participating inodes. Depending upon whether
162 * the target_name exists in the target directory, and
163 * whether the target directory is the same as the source
164 * directory, we can lock from 2 to 4 inodes.
165 */
166 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
167
168 /*
169 * Join all the inodes to the transaction. From this point on,
170 * we can rely on either trans_commit or trans_cancel to unlock
171 * them.
172 */
173 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
174 if (new_parent)
175 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
176 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
177 if (target_ip)
178 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
179
180 /*
181 * If we are using project inheritance, we only allow renames
182 * into our tree when the project IDs are the same; else the
183 * tree quota mechanism would be circumvented.
184 */
185 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
186 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
187 error = XFS_ERROR(EXDEV);
188 goto error_return;
189 }
190
191 /*
192 * Set up the target.
193 */
194 if (target_ip == NULL) {
195 /*
196 * If there's no space reservation, check the entry will
197 * fit before actually inserting it.
198 */
199 error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
200 if (error)
201 goto error_return;
202 /*
203 * If target does not exist and the rename crosses
204 * directories, adjust the target directory link count
205 * to account for the ".." reference from the new entry.
206 */
207 error = xfs_dir_createname(tp, target_dp, target_name,
208 src_ip->i_ino, &first_block,
209 &free_list, spaceres);
210 if (error == ENOSPC)
211 goto error_return;
212 if (error)
213 goto abort_return;
214
215 xfs_trans_ichgtime(tp, target_dp,
216 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
217
218 if (new_parent && src_is_directory) {
219 error = xfs_bumplink(tp, target_dp);
220 if (error)
221 goto abort_return;
222 }
223 } else { /* target_ip != NULL */
224 /*
225 * If target exists and it's a directory, check that both
226 * target and source are directories and that target can be
227 * destroyed, or that neither is a directory.
228 */
229 if (S_ISDIR(target_ip->i_d.di_mode)) {
230 /*
231 * Make sure target dir is empty.
232 */
233 if (!(xfs_dir_isempty(target_ip)) ||
234 (target_ip->i_d.di_nlink > 2)) {
235 error = XFS_ERROR(EEXIST);
236 goto error_return;
237 }
238 }
239
240 /*
241 * Link the source inode under the target name.
242 * If the source inode is a directory and we are moving
243 * it across directories, its ".." entry will be
244 * inconsistent until we replace that down below.
245 *
246 * In case there is already an entry with the same
247 * name at the destination directory, remove it first.
248 */
249 error = xfs_dir_replace(tp, target_dp, target_name,
250 src_ip->i_ino,
251 &first_block, &free_list, spaceres);
252 if (error)
253 goto abort_return;
254
255 xfs_trans_ichgtime(tp, target_dp,
256 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
257
258 /*
259 * Decrement the link count on the target since the target
260 * dir no longer points to it.
261 */
262 error = xfs_droplink(tp, target_ip);
263 if (error)
264 goto abort_return;
265
266 if (src_is_directory) {
267 /*
268 * Drop the link from the old "." entry.
269 */
270 error = xfs_droplink(tp, target_ip);
271 if (error)
272 goto abort_return;
273 }
274 } /* target_ip != NULL */
275
276 /*
277 * Remove the source.
278 */
279 if (new_parent && src_is_directory) {
280 /*
281 * Rewrite the ".." entry to point to the new
282 * directory.
283 */
284 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
285 target_dp->i_ino,
286 &first_block, &free_list, spaceres);
287 ASSERT(error != EEXIST);
288 if (error)
289 goto abort_return;
290 }
291
292 /*
293 * We always want to hit the ctime on the source inode.
294 *
295 * This isn't strictly required by the standards since the source
296 * inode isn't really being changed, but old unix file systems did
297 * it and some incremental backup programs won't work without it.
298 */
299 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
300 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
301
302 /*
303 * Adjust the link count on src_dp. This is necessary when
304 * renaming a directory, either within one parent when
305 * the target existed, or across two parent directories.
306 */
307 if (src_is_directory && (new_parent || target_ip != NULL)) {
308
309 /*
310 * Decrement link count on src_directory since the
311 * entry that's moved no longer points to it.
312 */
313 error = xfs_droplink(tp, src_dp);
314 if (error)
315 goto abort_return;
316 }
317
318 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
319 &first_block, &free_list, spaceres);
320 if (error)
321 goto abort_return;
322
323 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
324 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
325 if (new_parent)
326 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
327
328 /*
329 * If this is a synchronous mount, make sure that the
330 * rename transaction goes to disk before returning to
331 * the user.
332 */
333 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
334 xfs_trans_set_sync(tp);
335 }
336
337 error = xfs_bmap_finish(&tp, &free_list, &committed);
338 if (error) {
339 xfs_bmap_cancel(&free_list);
340 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
341 XFS_TRANS_ABORT));
342 goto std_return;
343 }
344
345 /*
346 * trans_commit will unlock src_ip, target_ip & decrement
347 * the vnode references.
348 */
349 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
350
351 abort_return:
352 cancel_flags |= XFS_TRANS_ABORT;
353 error_return:
354 xfs_bmap_cancel(&free_list);
355 xfs_trans_cancel(tp, cancel_flags);
356 std_return:
357 return error;
358 }
359