vfs: check i_nlink limits in vfs_{mkdir,rename_dir,link}
[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
cca28fb8 116 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
1da177e4 117
cfa853e4 118 new_parent = (src_dp != target_dp);
abbede1b 119 src_is_directory = S_ISDIR(src_ip->i_d.di_mode);
1da177e4 120
cfa853e4
CH
121 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
122 inodes, &num_inodes);
1da177e4 123
9d87c319 124 xfs_bmap_init(&free_list, &first_block);
1da177e4
LT
125 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
126 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
556b8b16 127 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
1da177e4
LT
128 error = xfs_trans_reserve(tp, spaceres, XFS_RENAME_LOG_RES(mp), 0,
129 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
130 if (error == ENOSPC) {
131 spaceres = 0;
132 error = xfs_trans_reserve(tp, 0, XFS_RENAME_LOG_RES(mp), 0,
133 XFS_TRANS_PERM_LOG_RES, XFS_RENAME_LOG_COUNT);
134 }
135 if (error) {
1da177e4 136 xfs_trans_cancel(tp, 0);
1ac74e01 137 goto std_return;
1da177e4
LT
138 }
139
140 /*
141 * Attach the dquots to the inodes
142 */
7d095257
CH
143 error = xfs_qm_vop_rename_dqattach(inodes);
144 if (error) {
1da177e4 145 xfs_trans_cancel(tp, cancel_flags);
1ac74e01 146 goto std_return;
1da177e4
LT
147 }
148
149 /*
cfa853e4
CH
150 * Lock all the participating inodes. Depending upon whether
151 * the target_name exists in the target directory, and
152 * whether the target directory is the same as the source
153 * directory, we can lock from 2 to 4 inodes.
154 */
155 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
156
1da177e4
LT
157 /*
158 * Join all the inodes to the transaction. From this point on,
159 * we can rely on either trans_commit or trans_cancel to unlock
898621d5 160 * them.
1da177e4 161 */
ddc3415a 162 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
898621d5 163 if (new_parent)
ddc3415a
CH
164 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
165 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
898621d5 166 if (target_ip)
ddc3415a 167 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
1da177e4 168
2175dd95
CH
169 /*
170 * If we are using project inheritance, we only allow renames
171 * into our tree when the project IDs are the same; else the
172 * tree quota mechanism would be circumvented.
173 */
174 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
6743099c 175 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2175dd95
CH
176 error = XFS_ERROR(EXDEV);
177 goto error_return;
178 }
179
1da177e4
LT
180 /*
181 * Set up the target.
182 */
183 if (target_ip == NULL) {
184 /*
185 * If there's no space reservation, check the entry will
186 * fit before actually inserting it.
187 */
556b8b16
BN
188 error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
189 if (error)
1da177e4 190 goto error_return;
1da177e4
LT
191 /*
192 * If target does not exist and the rename crosses
193 * directories, adjust the target directory link count
194 * to account for the ".." reference from the new entry.
195 */
f6c2d1fa 196 error = xfs_dir_createname(tp, target_dp, target_name,
556b8b16
BN
197 src_ip->i_ino, &first_block,
198 &free_list, spaceres);
f6c2d1fa 199 if (error == ENOSPC)
1da177e4 200 goto error_return;
f6c2d1fa 201 if (error)
1da177e4 202 goto abort_return;
dcd79a14
DC
203
204 xfs_trans_ichgtime(tp, target_dp,
205 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1da177e4
LT
206
207 if (new_parent && src_is_directory) {
208 error = xfs_bumplink(tp, target_dp);
f6c2d1fa 209 if (error)
1da177e4 210 goto abort_return;
1da177e4
LT
211 }
212 } else { /* target_ip != NULL */
1da177e4
LT
213 /*
214 * If target exists and it's a directory, check that both
215 * target and source are directories and that target can be
216 * destroyed, or that neither is a directory.
217 */
abbede1b 218 if (S_ISDIR(target_ip->i_d.di_mode)) {
1da177e4
LT
219 /*
220 * Make sure target dir is empty.
221 */
f6c2d1fa 222 if (!(xfs_dir_isempty(target_ip)) ||
1da177e4
LT
223 (target_ip->i_d.di_nlink > 2)) {
224 error = XFS_ERROR(EEXIST);
1da177e4
LT
225 goto error_return;
226 }
227 }
228
229 /*
230 * Link the source inode under the target name.
231 * If the source inode is a directory and we are moving
232 * it across directories, its ".." entry will be
233 * inconsistent until we replace that down below.
234 *
235 * In case there is already an entry with the same
236 * name at the destination directory, remove it first.
237 */
f6c2d1fa 238 error = xfs_dir_replace(tp, target_dp, target_name,
556b8b16 239 src_ip->i_ino,
f6c2d1fa
NS
240 &first_block, &free_list, spaceres);
241 if (error)
1da177e4 242 goto abort_return;
dcd79a14
DC
243
244 xfs_trans_ichgtime(tp, target_dp,
245 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1da177e4
LT
246
247 /*
248 * Decrement the link count on the target since the target
249 * dir no longer points to it.
250 */
251 error = xfs_droplink(tp, target_ip);
f6c2d1fa 252 if (error)
1da177e4 253 goto abort_return;
1da177e4
LT
254
255 if (src_is_directory) {
256 /*
257 * Drop the link from the old "." entry.
258 */
259 error = xfs_droplink(tp, target_ip);
f6c2d1fa 260 if (error)
1da177e4 261 goto abort_return;
1da177e4 262 }
1da177e4
LT
263 } /* target_ip != NULL */
264
265 /*
266 * Remove the source.
267 */
268 if (new_parent && src_is_directory) {
1da177e4
LT
269 /*
270 * Rewrite the ".." entry to point to the new
271 * directory.
272 */
556b8b16
BN
273 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
274 target_dp->i_ino,
f6c2d1fa 275 &first_block, &free_list, spaceres);
1da177e4 276 ASSERT(error != EEXIST);
f6c2d1fa 277 if (error)
1da177e4 278 goto abort_return;
1da177e4
LT
279 }
280
8f8670bb
CH
281 /*
282 * We always want to hit the ctime on the source inode.
283 *
284 * This isn't strictly required by the standards since the source
285 * inode isn't really being changed, but old unix file systems did
286 * it and some incremental backup programs won't work without it.
287 */
dcd79a14 288 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
05340d4a 289 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
8f8670bb 290
1da177e4
LT
291 /*
292 * Adjust the link count on src_dp. This is necessary when
293 * renaming a directory, either within one parent when
294 * the target existed, or across two parent directories.
295 */
296 if (src_is_directory && (new_parent || target_ip != NULL)) {
297
298 /*
299 * Decrement link count on src_directory since the
300 * entry that's moved no longer points to it.
301 */
302 error = xfs_droplink(tp, src_dp);
f6c2d1fa 303 if (error)
1da177e4 304 goto abort_return;
1da177e4
LT
305 }
306
556b8b16
BN
307 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
308 &first_block, &free_list, spaceres);
f6c2d1fa 309 if (error)
1da177e4 310 goto abort_return;
1da177e4 311
dcd79a14 312 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1da177e4 313 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
26c52951 314 if (new_parent)
1da177e4 315 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
1da177e4 316
1da177e4
LT
317 /*
318 * If this is a synchronous mount, make sure that the
319 * rename transaction goes to disk before returning to
320 * the user.
321 */
322 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
323 xfs_trans_set_sync(tp);
324 }
325
f7c99b6f 326 error = xfs_bmap_finish(&tp, &free_list, &committed);
1da177e4
LT
327 if (error) {
328 xfs_bmap_cancel(&free_list);
329 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
330 XFS_TRANS_ABORT));
1da177e4
LT
331 goto std_return;
332 }
333
334 /*
335 * trans_commit will unlock src_ip, target_ip & decrement
336 * the vnode references.
337 */
288699fe 338 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1da177e4
LT
339
340 abort_return:
341 cancel_flags |= XFS_TRANS_ABORT;
1da177e4
LT
342 error_return:
343 xfs_bmap_cancel(&free_list);
344 xfs_trans_cancel(tp, cancel_flags);
288699fe
CH
345 std_return:
346 return error;
1da177e4 347}