xfs: simplify buffer pinning
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / xfs / xfs_rename.c
CommitLineData
1da177e4 1/*
7b718769
NS
2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
1da177e4 4 *
7b718769
NS
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
1da177e4
LT
7 * published by the Free Software Foundation.
8 *
7b718769
NS
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.
1da177e4 13 *
7b718769
NS
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
1da177e4 17 */
1da177e4 18#include "xfs.h"
a844f451 19#include "xfs_fs.h"
1da177e4 20#include "xfs_types.h"
1da177e4 21#include "xfs_log.h"
a844f451 22#include "xfs_inum.h"
1da177e4
LT
23#include "xfs_trans.h"
24#include "xfs_sb.h"
da353b0d 25#include "xfs_ag.h"
1da177e4 26#include "xfs_dir2.h"
1da177e4 27#include "xfs_mount.h"
a844f451 28#include "xfs_da_btree.h"
1da177e4 29#include "xfs_bmap_btree.h"
1da177e4 30#include "xfs_dinode.h"
1da177e4 31#include "xfs_inode.h"
a844f451 32#include "xfs_inode_item.h"
1da177e4
LT
33#include "xfs_bmap.h"
34#include "xfs_error.h"
35#include "xfs_quota.h"
1da177e4
LT
36#include "xfs_utils.h"
37#include "xfs_trans_space.h"
a8272ce0 38#include "xfs_vnodeops.h"
0b1b213f 39#include "xfs_trace.h"
1da177e4
LT
40
41
1da177e4 42/*
cfa853e4 43 * Enter all inodes for a rename transaction into a sorted array.
1da177e4 44 */
cfa853e4
CH
45STATIC void
46xfs_sort_for_rename(
556b8b16
BN
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 */
cfa853e4 50 xfs_inode_t *ip2, /* in: inode of new entry, if it
1da177e4 51 already exists, NULL otherwise. */
556b8b16
BN
52 xfs_inode_t **i_tab,/* out: array of inode returned, sorted */
53 int *num_inodes) /* out: number of inodes in array */
1da177e4 54{
556b8b16 55 xfs_inode_t *temp;
1da177e4 56 int i, j;
1da177e4
LT
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;
cfa853e4 68 if (ip2) {
1da177e4
LT
69 *num_inodes = 4;
70 i_tab[3] = ip2;
cfa853e4
CH
71 } else {
72 *num_inodes = 3;
73 i_tab[3] = NULL;
1da177e4
LT
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 */
cfa853e4
CH
80 for (i = 0; i < *num_inodes; i++) {
81 for (j = 1; j < *num_inodes; j++) {
1da177e4
LT
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 }
1da177e4
LT
89}
90
1da177e4
LT
91/*
92 * xfs_rename
93 */
94int
95xfs_rename(
993386c1 96 xfs_inode_t *src_dp,
556b8b16
BN
97 struct xfs_name *src_name,
98 xfs_inode_t *src_ip,
3937be5b 99 xfs_inode_t *target_dp,
cfa853e4
CH
100 struct xfs_name *target_name,
101 xfs_inode_t *target_ip)
1da177e4 102{
cfa853e4 103 xfs_trans_t *tp = NULL;
993386c1 104 xfs_mount_t *mp = src_dp->i_mount;
1da177e4
LT
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];
1da177e4 113 int spaceres;
1da177e4 114 int num_inodes;
1da177e4 115
cf441eeb 116 xfs_itrace_entry(src_dp);
3937be5b 117 xfs_itrace_entry(target_dp);
1da177e4 118
cfa853e4
CH
119 new_parent = (src_dp != target_dp);
120 src_is_directory = ((src_ip->i_d.di_mode & S_IFMT) == S_IFDIR);
1da177e4 121
cfa853e4 122 if (src_is_directory) {
1da177e4
LT
123 /*
124 * Check for link count overflow on target_dp
125 */
cfa853e4 126 if (target_ip == NULL && new_parent &&
1da177e4 127 target_dp->i_d.di_nlink >= XFS_MAXLINK) {
1da177e4 128 error = XFS_ERROR(EMLINK);
cfa853e4 129 goto std_return;
1da177e4
LT
130 }
131 }
132
cfa853e4
CH
133 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
134 inodes, &num_inodes);
1da177e4 135
9d87c319 136 xfs_bmap_init(&free_list, &first_block);
1da177e4
LT
137 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
138 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
556b8b16 139 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
1da177e4
LT
140 error = xfs_trans_reserve(tp, spaceres, XFS_RENAME_LOG_RES(mp), 0,
141 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
142 if (error == ENOSPC) {
143 spaceres = 0;
144 error = xfs_trans_reserve(tp, 0, XFS_RENAME_LOG_RES(mp), 0,
145 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
146 }
147 if (error) {
1da177e4 148 xfs_trans_cancel(tp, 0);
1ac74e01 149 goto std_return;
1da177e4
LT
150 }
151
152 /*
153 * Attach the dquots to the inodes
154 */
7d095257
CH
155 error = xfs_qm_vop_rename_dqattach(inodes);
156 if (error) {
1da177e4 157 xfs_trans_cancel(tp, cancel_flags);
1ac74e01 158 goto std_return;
1da177e4
LT
159 }
160
161 /*
cfa853e4
CH
162 * Lock all the participating inodes. Depending upon whether
163 * the target_name exists in the target directory, and
164 * whether the target directory is the same as the source
165 * directory, we can lock from 2 to 4 inodes.
166 */
167 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
168
1da177e4
LT
169 /*
170 * Join all the inodes to the transaction. From this point on,
171 * we can rely on either trans_commit or trans_cancel to unlock
172 * them. Note that we need to add a vnode reference to the
173 * directories since trans_commit & trans_cancel will decrement
174 * them when they unlock the inodes. Also, we need to be careful
175 * not to add an inode to the transaction more than once.
176 */
3937be5b 177 IHOLD(src_dp);
1da177e4 178 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
1ac74e01 179
1da177e4 180 if (new_parent) {
3937be5b 181 IHOLD(target_dp);
1da177e4
LT
182 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
183 }
1ac74e01
CH
184
185 IHOLD(src_ip);
186 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
187
188 if (target_ip) {
189 IHOLD(target_ip);
1da177e4
LT
190 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
191 }
192
2175dd95
CH
193 /*
194 * If we are using project inheritance, we only allow renames
195 * into our tree when the project IDs are the same; else the
196 * tree quota mechanism would be circumvented.
197 */
198 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
199 (target_dp->i_d.di_projid != src_ip->i_d.di_projid))) {
200 error = XFS_ERROR(EXDEV);
201 goto error_return;
202 }
203
1da177e4
LT
204 /*
205 * Set up the target.
206 */
207 if (target_ip == NULL) {
208 /*
209 * If there's no space reservation, check the entry will
210 * fit before actually inserting it.
211 */
556b8b16
BN
212 error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
213 if (error)
1da177e4 214 goto error_return;
1da177e4
LT
215 /*
216 * If target does not exist and the rename crosses
217 * directories, adjust the target directory link count
218 * to account for the ".." reference from the new entry.
219 */
f6c2d1fa 220 error = xfs_dir_createname(tp, target_dp, target_name,
556b8b16
BN
221 src_ip->i_ino, &first_block,
222 &free_list, spaceres);
f6c2d1fa 223 if (error == ENOSPC)
1da177e4 224 goto error_return;
f6c2d1fa 225 if (error)
1da177e4 226 goto abort_return;
1da177e4
LT
227 xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
228
229 if (new_parent && src_is_directory) {
230 error = xfs_bumplink(tp, target_dp);
f6c2d1fa 231 if (error)
1da177e4 232 goto abort_return;
1da177e4
LT
233 }
234 } else { /* target_ip != NULL */
1da177e4
LT
235 /*
236 * If target exists and it's a directory, check that both
237 * target and source are directories and that target can be
238 * destroyed, or that neither is a directory.
239 */
240 if ((target_ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
241 /*
242 * Make sure target dir is empty.
243 */
f6c2d1fa 244 if (!(xfs_dir_isempty(target_ip)) ||
1da177e4
LT
245 (target_ip->i_d.di_nlink > 2)) {
246 error = XFS_ERROR(EEXIST);
1da177e4
LT
247 goto error_return;
248 }
249 }
250
251 /*
252 * Link the source inode under the target name.
253 * If the source inode is a directory and we are moving
254 * it across directories, its ".." entry will be
255 * inconsistent until we replace that down below.
256 *
257 * In case there is already an entry with the same
258 * name at the destination directory, remove it first.
259 */
f6c2d1fa 260 error = xfs_dir_replace(tp, target_dp, target_name,
556b8b16 261 src_ip->i_ino,
f6c2d1fa
NS
262 &first_block, &free_list, spaceres);
263 if (error)
1da177e4 264 goto abort_return;
1da177e4
LT
265 xfs_ichgtime(target_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
266
267 /*
268 * Decrement the link count on the target since the target
269 * dir no longer points to it.
270 */
271 error = xfs_droplink(tp, target_ip);
f6c2d1fa 272 if (error)
1da177e4 273 goto abort_return;
1da177e4
LT
274
275 if (src_is_directory) {
276 /*
277 * Drop the link from the old "." entry.
278 */
279 error = xfs_droplink(tp, target_ip);
f6c2d1fa 280 if (error)
1da177e4 281 goto abort_return;
1da177e4 282 }
1da177e4
LT
283 } /* target_ip != NULL */
284
285 /*
286 * Remove the source.
287 */
288 if (new_parent && src_is_directory) {
1da177e4
LT
289 /*
290 * Rewrite the ".." entry to point to the new
291 * directory.
292 */
556b8b16
BN
293 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
294 target_dp->i_ino,
f6c2d1fa 295 &first_block, &free_list, spaceres);
1da177e4 296 ASSERT(error != EEXIST);
f6c2d1fa 297 if (error)
1da177e4 298 goto abort_return;
1da177e4
LT
299 }
300
8f8670bb
CH
301 /*
302 * We always want to hit the ctime on the source inode.
303 *
304 * This isn't strictly required by the standards since the source
305 * inode isn't really being changed, but old unix file systems did
306 * it and some incremental backup programs won't work without it.
307 */
308 xfs_ichgtime(src_ip, XFS_ICHGTIME_CHG);
309
1da177e4
LT
310 /*
311 * Adjust the link count on src_dp. This is necessary when
312 * renaming a directory, either within one parent when
313 * the target existed, or across two parent directories.
314 */
315 if (src_is_directory && (new_parent || target_ip != NULL)) {
316
317 /*
318 * Decrement link count on src_directory since the
319 * entry that's moved no longer points to it.
320 */
321 error = xfs_droplink(tp, src_dp);
f6c2d1fa 322 if (error)
1da177e4 323 goto abort_return;
1da177e4
LT
324 }
325
556b8b16
BN
326 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
327 &first_block, &free_list, spaceres);
f6c2d1fa 328 if (error)
1da177e4 329 goto abort_return;
1da177e4 330
26c52951 331 xfs_ichgtime(src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1da177e4 332 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
26c52951 333 if (new_parent)
1da177e4 334 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
1da177e4 335
1da177e4
LT
336 /*
337 * If this is a synchronous mount, make sure that the
338 * rename transaction goes to disk before returning to
339 * the user.
340 */
341 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
342 xfs_trans_set_sync(tp);
343 }
344
f7c99b6f 345 error = xfs_bmap_finish(&tp, &free_list, &committed);
1da177e4
LT
346 if (error) {
347 xfs_bmap_cancel(&free_list);
348 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
349 XFS_TRANS_ABORT));
1da177e4
LT
350 goto std_return;
351 }
352
353 /*
354 * trans_commit will unlock src_ip, target_ip & decrement
355 * the vnode references.
356 */
288699fe 357 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1da177e4
LT
358
359 abort_return:
360 cancel_flags |= XFS_TRANS_ABORT;
1da177e4
LT
361 error_return:
362 xfs_bmap_cancel(&free_list);
363 xfs_trans_cancel(tp, cancel_flags);
288699fe
CH
364 std_return:
365 return error;
1da177e4 366}