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_dmapi.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_btree.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_dir2_sf.h"
32 #include "xfs_attr_sf.h"
33 #include "xfs_dinode.h"
34 #include "xfs_inode.h"
35 #include "xfs_inode_item.h"
36 #include "xfs_bmap.h"
37 #include "xfs_error.h"
38 #include "xfs_quota.h"
39 #include "xfs_utils.h"
40 #include "xfs_trans_space.h"
41 #include "xfs_vnodeops.h"
42
43
44 /*
45 * Enter all inodes for a rename transaction into a sorted array.
46 */
47 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)48 xfs_sort_for_rename(
49 xfs_inode_t *dp1, /* in: old (source) directory inode */
50 xfs_inode_t *dp2, /* in: new (target) directory inode */
51 xfs_inode_t *ip1, /* in: inode of old entry */
52 xfs_inode_t *ip2, /* in: inode of new entry, if it
53 already exists, NULL otherwise. */
54 xfs_inode_t **i_tab,/* out: array of inode returned, sorted */
55 int *num_inodes) /* out: number of inodes in array */
56 {
57 xfs_inode_t *temp;
58 int i, j;
59
60 /*
61 * i_tab contains a list of pointers to inodes. We initialize
62 * the table here & we'll sort it. We will then use it to
63 * order the acquisition of the inode locks.
64 *
65 * Note that the table may contain duplicates. e.g., dp1 == dp2.
66 */
67 i_tab[0] = dp1;
68 i_tab[1] = dp2;
69 i_tab[2] = ip1;
70 if (ip2) {
71 *num_inodes = 4;
72 i_tab[3] = ip2;
73 } else {
74 *num_inodes = 3;
75 i_tab[3] = NULL;
76 }
77
78 /*
79 * Sort the elements via bubble sort. (Remember, there are at
80 * most 4 elements to sort, so this is adequate.)
81 */
82 for (i = 0; i < *num_inodes; i++) {
83 for (j = 1; j < *num_inodes; j++) {
84 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
85 temp = i_tab[j];
86 i_tab[j] = i_tab[j-1];
87 i_tab[j-1] = temp;
88 }
89 }
90 }
91 }
92
93 /*
94 * xfs_rename
95 */
96 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)97 xfs_rename(
98 xfs_inode_t *src_dp,
99 struct xfs_name *src_name,
100 xfs_inode_t *src_ip,
101 xfs_inode_t *target_dp,
102 struct xfs_name *target_name,
103 xfs_inode_t *target_ip)
104 {
105 xfs_trans_t *tp = NULL;
106 xfs_mount_t *mp = src_dp->i_mount;
107 int new_parent; /* moving to a new dir */
108 int src_is_directory; /* src_name is a directory */
109 int error;
110 xfs_bmap_free_t free_list;
111 xfs_fsblock_t first_block;
112 int cancel_flags;
113 int committed;
114 xfs_inode_t *inodes[4];
115 int spaceres;
116 int num_inodes;
117
118 xfs_itrace_entry(src_dp);
119 xfs_itrace_entry(target_dp);
120
121 if (DM_EVENT_ENABLED(src_dp, DM_EVENT_RENAME) ||
122 DM_EVENT_ENABLED(target_dp, DM_EVENT_RENAME)) {
123 error = XFS_SEND_NAMESP(mp, DM_EVENT_RENAME,
124 src_dp, DM_RIGHT_NULL,
125 target_dp, DM_RIGHT_NULL,
126 src_name->name, target_name->name,
127 0, 0, 0);
128 if (error)
129 return error;
130 }
131 /* Return through std_return after this point. */
132
133 new_parent = (src_dp != target_dp);
134 src_is_directory = ((src_ip->i_d.di_mode & S_IFMT) == S_IFDIR);
135
136 if (src_is_directory) {
137 /*
138 * Check for link count overflow on target_dp
139 */
140 if (target_ip == NULL && new_parent &&
141 target_dp->i_d.di_nlink >= XFS_MAXLINK) {
142 error = XFS_ERROR(EMLINK);
143 goto std_return;
144 }
145 }
146
147 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
148 inodes, &num_inodes);
149
150 xfs_bmap_init(&free_list, &first_block);
151 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
152 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
153 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
154 error = xfs_trans_reserve(tp, spaceres, XFS_RENAME_LOG_RES(mp), 0,
155 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
156 if (error == ENOSPC) {
157 spaceres = 0;
158 error = xfs_trans_reserve(tp, 0, XFS_RENAME_LOG_RES(mp), 0,
159 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
160 }
161 if (error) {
162 xfs_trans_cancel(tp, 0);
163 goto std_return;
164 }
165
166 /*
167 * Attach the dquots to the inodes
168 */
169 if ((error = XFS_QM_DQVOPRENAME(mp, inodes))) {
170 xfs_trans_cancel(tp, cancel_flags);
171 goto std_return;
172 }
173
174 /*
175 * Lock all the participating inodes. Depending upon whether
176 * the target_name exists in the target directory, and
177 * whether the target directory is the same as the source
178 * directory, we can lock from 2 to 4 inodes.
179 */
180 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
181
182 /*
183 * Join all the inodes to the transaction. From this point on,
184 * we can rely on either trans_commit or trans_cancel to unlock
185 * them. Note that we need to add a vnode reference to the
186 * directories since trans_commit & trans_cancel will decrement
187 * them when they unlock the inodes. Also, we need to be careful
188 * not to add an inode to the transaction more than once.
189 */
190 IHOLD(src_dp);
191 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
192
193 if (new_parent) {
194 IHOLD(target_dp);
195 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
196 }
197
198 IHOLD(src_ip);
199 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
200
201 if (target_ip) {
202 IHOLD(target_ip);
203 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
204 }
205
206 /*
207 * If we are using project inheritance, we only allow renames
208 * into our tree when the project IDs are the same; else the
209 * tree quota mechanism would be circumvented.
210 */
211 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
212 (target_dp->i_d.di_projid != src_ip->i_d.di_projid))) {
213 error = XFS_ERROR(EXDEV);
214 goto error_return;
215 }
216
217 /*
218 * Set up the target.
219 */
220 if (target_ip == NULL) {
221 /*
222 * If there's no space reservation, check the entry will
223 * fit before actually inserting it.
224 */
225 error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
226 if (error)
227 goto error_return;
228 /*
229 * If target does not exist and the rename crosses
230 * directories, adjust the target directory link count
231 * to account for the ".." reference from the new entry.
232 */
233 error = xfs_dir_createname(tp, target_dp, target_name,
234 src_ip->i_ino, &first_block,
235 &free_list, spaceres);
236 if (error == ENOSPC)
237 goto error_return;
238 if (error)
239 goto abort_return;
240 xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
241
242 if (new_parent && src_is_directory) {
243 error = xfs_bumplink(tp, target_dp);
244 if (error)
245 goto abort_return;
246 }
247 } else { /* target_ip != NULL */
248 /*
249 * If target exists and it's a directory, check that both
250 * target and source are directories and that target can be
251 * destroyed, or that neither is a directory.
252 */
253 if ((target_ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
254 /*
255 * Make sure target dir is empty.
256 */
257 if (!(xfs_dir_isempty(target_ip)) ||
258 (target_ip->i_d.di_nlink > 2)) {
259 error = XFS_ERROR(EEXIST);
260 goto error_return;
261 }
262 }
263
264 /*
265 * Link the source inode under the target name.
266 * If the source inode is a directory and we are moving
267 * it across directories, its ".." entry will be
268 * inconsistent until we replace that down below.
269 *
270 * In case there is already an entry with the same
271 * name at the destination directory, remove it first.
272 */
273 error = xfs_dir_replace(tp, target_dp, target_name,
274 src_ip->i_ino,
275 &first_block, &free_list, spaceres);
276 if (error)
277 goto abort_return;
278 xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
279
280 /*
281 * Decrement the link count on the target since the target
282 * dir no longer points to it.
283 */
284 error = xfs_droplink(tp, target_ip);
285 if (error)
286 goto abort_return;
287
288 if (src_is_directory) {
289 /*
290 * Drop the link from the old "." entry.
291 */
292 error = xfs_droplink(tp, target_ip);
293 if (error)
294 goto abort_return;
295 }
296 } /* target_ip != NULL */
297
298 /*
299 * Remove the source.
300 */
301 if (new_parent && src_is_directory) {
302 /*
303 * Rewrite the ".." entry to point to the new
304 * directory.
305 */
306 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
307 target_dp->i_ino,
308 &first_block, &free_list, spaceres);
309 ASSERT(error != EEXIST);
310 if (error)
311 goto abort_return;
312 }
313
314 /*
315 * We always want to hit the ctime on the source inode.
316 *
317 * This isn't strictly required by the standards since the source
318 * inode isn't really being changed, but old unix file systems did
319 * it and some incremental backup programs won't work without it.
320 */
321 xfs_ichgtime(src_ip, XFS_ICHGTIME_CHG);
322
323 /*
324 * Adjust the link count on src_dp. This is necessary when
325 * renaming a directory, either within one parent when
326 * the target existed, or across two parent directories.
327 */
328 if (src_is_directory && (new_parent || target_ip != NULL)) {
329
330 /*
331 * Decrement link count on src_directory since the
332 * entry that's moved no longer points to it.
333 */
334 error = xfs_droplink(tp, src_dp);
335 if (error)
336 goto abort_return;
337 }
338
339 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
340 &first_block, &free_list, spaceres);
341 if (error)
342 goto abort_return;
343
344 xfs_ichgtime(src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
345 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
346 if (new_parent)
347 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
348
349 /*
350 * If this is a synchronous mount, make sure that the
351 * rename transaction goes to disk before returning to
352 * the user.
353 */
354 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
355 xfs_trans_set_sync(tp);
356 }
357
358 error = xfs_bmap_finish(&tp, &free_list, &committed);
359 if (error) {
360 xfs_bmap_cancel(&free_list);
361 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
362 XFS_TRANS_ABORT));
363 goto std_return;
364 }
365
366 /*
367 * trans_commit will unlock src_ip, target_ip & decrement
368 * the vnode references.
369 */
370 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
371
372 /* Fall through to std_return with error = 0 or errno from
373 * xfs_trans_commit */
374 std_return:
375 if (DM_EVENT_ENABLED(src_dp, DM_EVENT_POSTRENAME) ||
376 DM_EVENT_ENABLED(target_dp, DM_EVENT_POSTRENAME)) {
377 (void) XFS_SEND_NAMESP (mp, DM_EVENT_POSTRENAME,
378 src_dp, DM_RIGHT_NULL,
379 target_dp, DM_RIGHT_NULL,
380 src_name->name, target_name->name,
381 0, error, 0);
382 }
383 return error;
384
385 abort_return:
386 cancel_flags |= XFS_TRANS_ABORT;
387 /* FALLTHROUGH */
388 error_return:
389 xfs_bmap_cancel(&free_list);
390 xfs_trans_cancel(tp, cancel_flags);
391 goto std_return;
392 }
393