1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/kernel.h>
16#include <linux/slab.h>
17#include <linux/fs.h>
18#include <linux/crc32.h>
19#include <linux/jffs2.h>
20#include "jffs2_fs_i.h"
21#include "jffs2_fs_sb.h"
22#include <linux/time.h>
23#include "nodelist.h"
24
25static int jffs2_readdir (struct file *, struct dir_context *);
26
27static int jffs2_create (struct mnt_idmap *, struct inode *,
28 struct dentry *, umode_t, bool);
29static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
30 unsigned int);
31static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
32static int jffs2_unlink (struct inode *,struct dentry *);
33static int jffs2_symlink (struct mnt_idmap *, struct inode *,
34 struct dentry *, const char *);
35static int jffs2_mkdir (struct mnt_idmap *, struct inode *,struct dentry *,
36 umode_t);
37static int jffs2_rmdir (struct inode *,struct dentry *);
38static int jffs2_mknod (struct mnt_idmap *, struct inode *,struct dentry *,
39 umode_t,dev_t);
40static int jffs2_rename (struct mnt_idmap *, struct inode *,
41 struct dentry *, struct inode *, struct dentry *,
42 unsigned int);
43
44const struct file_operations jffs2_dir_operations =
45{
46 .read = generic_read_dir,
47 .iterate_shared=jffs2_readdir,
48 .unlocked_ioctl=jffs2_ioctl,
49 .fsync = jffs2_fsync,
50 .llseek = generic_file_llseek,
51};
52
53
54const struct inode_operations jffs2_dir_inode_operations =
55{
56 .create = jffs2_create,
57 .lookup = jffs2_lookup,
58 .link = jffs2_link,
59 .unlink = jffs2_unlink,
60 .symlink = jffs2_symlink,
61 .mkdir = jffs2_mkdir,
62 .rmdir = jffs2_rmdir,
63 .mknod = jffs2_mknod,
64 .rename = jffs2_rename,
65 .get_inode_acl = jffs2_get_acl,
66 .set_acl = jffs2_set_acl,
67 .setattr = jffs2_setattr,
68 .listxattr = jffs2_listxattr,
69};
70
71/***********************************************************************/
72
73
74/* We keep the dirent list sorted in increasing order of name hash,
75 and we use the same hash function as the dentries. Makes this
76 nice and simple
77*/
78static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
79 unsigned int flags)
80{
81 struct jffs2_inode_info *dir_f;
82 struct jffs2_full_dirent *fd = NULL, *fd_list;
83 uint32_t ino = 0;
84 struct inode *inode = NULL;
85 unsigned int nhash;
86
87 jffs2_dbg(1, "jffs2_lookup()\n");
88
89 if (target->d_name.len > JFFS2_MAX_NAME_LEN)
90 return ERR_PTR(error: -ENAMETOOLONG);
91
92 dir_f = JFFS2_INODE_INFO(dir_i);
93
94 /* The 'nhash' on the fd_list is not the same as the dentry hash */
95 nhash = full_name_hash(NULL, target->d_name.name, target->d_name.len);
96
97 mutex_lock(&dir_f->sem);
98
99 /* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
100 for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= nhash; fd_list = fd_list->next) {
101 if (fd_list->nhash == nhash &&
102 (!fd || fd_list->version > fd->version) &&
103 strlen(fd_list->name) == target->d_name.len &&
104 !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
105 fd = fd_list;
106 }
107 }
108 if (fd)
109 ino = fd->ino;
110 mutex_unlock(lock: &dir_f->sem);
111 if (ino) {
112 inode = jffs2_iget(dir_i->i_sb, ino);
113 if (IS_ERR(ptr: inode))
114 pr_warn("iget() failed for ino #%u\n", ino);
115 }
116
117 return d_splice_alias(inode, target);
118}
119
120/***********************************************************************/
121
122
123static int jffs2_readdir(struct file *file, struct dir_context *ctx)
124{
125 struct inode *inode = file_inode(f: file);
126 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
127 struct jffs2_full_dirent *fd;
128 unsigned long curofs = 1;
129
130 jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino);
131
132 if (!dir_emit_dots(file, ctx))
133 return 0;
134
135 mutex_lock(&f->sem);
136 for (fd = f->dents; fd; fd = fd->next) {
137 curofs++;
138 /* First loop: curofs = 2; pos = 2 */
139 if (curofs < ctx->pos) {
140 jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
141 fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos);
142 continue;
143 }
144 if (!fd->ino) {
145 jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
146 fd->name);
147 ctx->pos++;
148 continue;
149 }
150 jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
151 (unsigned long)ctx->pos, fd->name, fd->ino, fd->type);
152 if (!dir_emit(ctx, name: fd->name, strlen(fd->name), ino: fd->ino, type: fd->type))
153 break;
154 ctx->pos++;
155 }
156 mutex_unlock(lock: &f->sem);
157 return 0;
158}
159
160/***********************************************************************/
161
162
163static int jffs2_create(struct mnt_idmap *idmap, struct inode *dir_i,
164 struct dentry *dentry, umode_t mode, bool excl)
165{
166 struct jffs2_raw_inode *ri;
167 struct jffs2_inode_info *f, *dir_f;
168 struct jffs2_sb_info *c;
169 struct inode *inode;
170 int ret;
171
172 ri = jffs2_alloc_raw_inode();
173 if (!ri)
174 return -ENOMEM;
175
176 c = JFFS2_SB_INFO(dir_i->i_sb);
177
178 jffs2_dbg(1, "%s()\n", __func__);
179
180 inode = jffs2_new_inode(dir_i, mode, ri);
181
182 if (IS_ERR(ptr: inode)) {
183 jffs2_dbg(1, "jffs2_new_inode() failed\n");
184 jffs2_free_raw_inode(ri);
185 return PTR_ERR(ptr: inode);
186 }
187
188 inode->i_op = &jffs2_file_inode_operations;
189 inode->i_fop = &jffs2_file_operations;
190 inode->i_mapping->a_ops = &jffs2_file_address_operations;
191 inode->i_mapping->nrpages = 0;
192
193 f = JFFS2_INODE_INFO(inode);
194 dir_f = JFFS2_INODE_INFO(dir_i);
195
196 /* jffs2_do_create() will want to lock it, _after_ reserving
197 space and taking c-alloc_sem. If we keep it locked here,
198 lockdep gets unhappy (although it's a false positive;
199 nothing else will be looking at this inode yet so there's
200 no chance of AB-BA deadlock involving its f->sem). */
201 mutex_unlock(lock: &f->sem);
202
203 ret = jffs2_do_create(c, dir_f, f, ri, qstr: &dentry->d_name);
204 if (ret)
205 goto fail;
206
207 inode_set_mtime_to_ts(inode: dir_i,
208 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(je32_to_cpu(ri->ctime))));
209
210 jffs2_free_raw_inode(ri);
211
212 jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
213 __func__, inode->i_ino, inode->i_mode, inode->i_nlink,
214 f->inocache->pino_nlink, inode->i_mapping->nrpages);
215
216 d_instantiate_new(dentry, inode);
217 return 0;
218
219 fail:
220 iget_failed(inode);
221 jffs2_free_raw_inode(ri);
222 return ret;
223}
224
225/***********************************************************************/
226
227
228static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
229{
230 struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
231 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
232 struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(d_inode(dentry));
233 int ret;
234 uint32_t now = JFFS2_NOW();
235
236 ret = jffs2_do_unlink(c, dir_f, name: dentry->d_name.name,
237 namelen: dentry->d_name.len, dead_f, time: now);
238 if (dead_f->inocache)
239 set_nlink(inode: d_inode(dentry), nlink: dead_f->inocache->pino_nlink);
240 if (!ret)
241 inode_set_mtime_to_ts(inode: dir_i,
242 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(now)));
243 return ret;
244}
245/***********************************************************************/
246
247
248static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
249{
250 struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_sb);
251 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
252 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
253 int ret;
254 uint8_t type;
255 uint32_t now;
256
257 /* Don't let people make hard links to bad inodes. */
258 if (!f->inocache)
259 return -EIO;
260
261 if (d_is_dir(dentry: old_dentry))
262 return -EPERM;
263
264 /* XXX: This is ugly */
265 type = (d_inode(dentry: old_dentry)->i_mode & S_IFMT) >> 12;
266 if (!type) type = DT_REG;
267
268 now = JFFS2_NOW();
269 ret = jffs2_do_link(c, dir_f, ino: f->inocache->ino, type, name: dentry->d_name.name, namelen: dentry->d_name.len, time: now);
270
271 if (!ret) {
272 mutex_lock(&f->sem);
273 set_nlink(inode: d_inode(dentry: old_dentry), nlink: ++f->inocache->pino_nlink);
274 mutex_unlock(lock: &f->sem);
275 d_instantiate(dentry, d_inode(dentry: old_dentry));
276 inode_set_mtime_to_ts(inode: dir_i,
277 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(now)));
278 ihold(inode: d_inode(dentry: old_dentry));
279 }
280 return ret;
281}
282
283/***********************************************************************/
284
285static int jffs2_symlink (struct mnt_idmap *idmap, struct inode *dir_i,
286 struct dentry *dentry, const char *target)
287{
288 struct jffs2_inode_info *f, *dir_f;
289 struct jffs2_sb_info *c;
290 struct inode *inode;
291 struct jffs2_raw_inode *ri;
292 struct jffs2_raw_dirent *rd;
293 struct jffs2_full_dnode *fn;
294 struct jffs2_full_dirent *fd;
295 int namelen;
296 uint32_t alloclen;
297 int ret, targetlen = strlen(target);
298
299 /* FIXME: If you care. We'd need to use frags for the target
300 if it grows much more than this */
301 if (targetlen > 254)
302 return -ENAMETOOLONG;
303
304 ri = jffs2_alloc_raw_inode();
305
306 if (!ri)
307 return -ENOMEM;
308
309 c = JFFS2_SB_INFO(dir_i->i_sb);
310
311 /* Try to reserve enough space for both node and dirent.
312 * Just the node will do for now, though
313 */
314 namelen = dentry->d_name.len;
315 ret = jffs2_reserve_space(c, minsize: sizeof(*ri) + targetlen, len: &alloclen,
316 ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
317
318 if (ret) {
319 jffs2_free_raw_inode(ri);
320 return ret;
321 }
322
323 inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
324
325 if (IS_ERR(ptr: inode)) {
326 jffs2_free_raw_inode(ri);
327 jffs2_complete_reservation(c);
328 return PTR_ERR(ptr: inode);
329 }
330
331 inode->i_op = &jffs2_symlink_inode_operations;
332
333 f = JFFS2_INODE_INFO(inode);
334
335 inode->i_size = targetlen;
336 ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
337 ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
338 ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
339
340 ri->compr = JFFS2_COMPR_NONE;
341 ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
342 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
343
344 fn = jffs2_write_dnode(c, f, ri, data: target, datalen: targetlen, ALLOC_NORMAL);
345
346 jffs2_free_raw_inode(ri);
347
348 if (IS_ERR(ptr: fn)) {
349 /* Eeek. Wave bye bye */
350 mutex_unlock(lock: &f->sem);
351 jffs2_complete_reservation(c);
352 ret = PTR_ERR(ptr: fn);
353 goto fail;
354 }
355
356 /* We use f->target field to store the target path. */
357 f->target = kmemdup(p: target, size: targetlen + 1, GFP_KERNEL);
358 if (!f->target) {
359 pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1);
360 mutex_unlock(lock: &f->sem);
361 jffs2_complete_reservation(c);
362 ret = -ENOMEM;
363 goto fail;
364 }
365 inode->i_link = f->target;
366
367 jffs2_dbg(1, "%s(): symlink's target '%s' cached\n",
368 __func__, (char *)f->target);
369
370 /* No data here. Only a metadata node, which will be
371 obsoleted by the first data write
372 */
373 f->metadata = fn;
374 mutex_unlock(lock: &f->sem);
375
376 jffs2_complete_reservation(c);
377
378 ret = jffs2_init_security(inode, dir: dir_i, qstr: &dentry->d_name);
379 if (ret)
380 goto fail;
381
382 ret = jffs2_init_acl_post(inode);
383 if (ret)
384 goto fail;
385
386 ret = jffs2_reserve_space(c, minsize: sizeof(*rd)+namelen, len: &alloclen,
387 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
388 if (ret)
389 goto fail;
390
391 rd = jffs2_alloc_raw_dirent();
392 if (!rd) {
393 /* Argh. Now we treat it like a normal delete */
394 jffs2_complete_reservation(c);
395 ret = -ENOMEM;
396 goto fail;
397 }
398
399 dir_f = JFFS2_INODE_INFO(dir_i);
400 mutex_lock(&dir_f->sem);
401
402 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
403 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
404 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
405 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
406
407 rd->pino = cpu_to_je32(dir_i->i_ino);
408 rd->version = cpu_to_je32(++dir_f->highest_version);
409 rd->ino = cpu_to_je32(inode->i_ino);
410 rd->mctime = cpu_to_je32(JFFS2_NOW());
411 rd->nsize = namelen;
412 rd->type = DT_LNK;
413 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
414 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
415
416 fd = jffs2_write_dirent(c, f: dir_f, rd, name: dentry->d_name.name, namelen, ALLOC_NORMAL);
417
418 if (IS_ERR(ptr: fd)) {
419 /* dirent failed to write. Delete the inode normally
420 as if it were the final unlink() */
421 jffs2_complete_reservation(c);
422 jffs2_free_raw_dirent(rd);
423 mutex_unlock(lock: &dir_f->sem);
424 ret = PTR_ERR(ptr: fd);
425 goto fail;
426 }
427
428 inode_set_mtime_to_ts(inode: dir_i,
429 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(je32_to_cpu(rd->mctime))));
430
431 jffs2_free_raw_dirent(rd);
432
433 /* Link the fd into the inode's list, obsoleting an old
434 one if necessary. */
435 jffs2_add_fd_to_list(c, new: fd, list: &dir_f->dents);
436
437 mutex_unlock(lock: &dir_f->sem);
438 jffs2_complete_reservation(c);
439
440 d_instantiate_new(dentry, inode);
441 return 0;
442
443 fail:
444 iget_failed(inode);
445 return ret;
446}
447
448
449static int jffs2_mkdir (struct mnt_idmap *idmap, struct inode *dir_i,
450 struct dentry *dentry, umode_t mode)
451{
452 struct jffs2_inode_info *f, *dir_f;
453 struct jffs2_sb_info *c;
454 struct inode *inode;
455 struct jffs2_raw_inode *ri;
456 struct jffs2_raw_dirent *rd;
457 struct jffs2_full_dnode *fn;
458 struct jffs2_full_dirent *fd;
459 int namelen;
460 uint32_t alloclen;
461 int ret;
462
463 mode |= S_IFDIR;
464
465 ri = jffs2_alloc_raw_inode();
466 if (!ri)
467 return -ENOMEM;
468
469 c = JFFS2_SB_INFO(dir_i->i_sb);
470
471 /* Try to reserve enough space for both node and dirent.
472 * Just the node will do for now, though
473 */
474 namelen = dentry->d_name.len;
475 ret = jffs2_reserve_space(c, minsize: sizeof(*ri), len: &alloclen, ALLOC_NORMAL,
476 JFFS2_SUMMARY_INODE_SIZE);
477
478 if (ret) {
479 jffs2_free_raw_inode(ri);
480 return ret;
481 }
482
483 inode = jffs2_new_inode(dir_i, mode, ri);
484
485 if (IS_ERR(ptr: inode)) {
486 jffs2_free_raw_inode(ri);
487 jffs2_complete_reservation(c);
488 return PTR_ERR(ptr: inode);
489 }
490
491 inode->i_op = &jffs2_dir_inode_operations;
492 inode->i_fop = &jffs2_dir_operations;
493
494 f = JFFS2_INODE_INFO(inode);
495
496 /* Directories get nlink 2 at start */
497 set_nlink(inode, nlink: 2);
498 /* but ic->pino_nlink is the parent ino# */
499 f->inocache->pino_nlink = dir_i->i_ino;
500
501 ri->data_crc = cpu_to_je32(0);
502 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
503
504 fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
505
506 jffs2_free_raw_inode(ri);
507
508 if (IS_ERR(fn)) {
509 /* Eeek. Wave bye bye */
510 mutex_unlock(&f->sem);
511 jffs2_complete_reservation(c);
512 ret = PTR_ERR(fn);
513 goto fail;
514 }
515 /* No data here. Only a metadata node, which will be
516 obsoleted by the first data write
517 */
518 f->metadata = fn;
519 mutex_unlock(&f->sem);
520
521 jffs2_complete_reservation(c);
522
523 ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
524 if (ret)
525 goto fail;
526
527 ret = jffs2_init_acl_post(inode);
528 if (ret)
529 goto fail;
530
531 ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
532 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
533 if (ret)
534 goto fail;
535
536 rd = jffs2_alloc_raw_dirent();
537 if (!rd) {
538 /* Argh. Now we treat it like a normal delete */
539 jffs2_complete_reservation(c);
540 ret = -ENOMEM;
541 goto fail;
542 }
543
544 dir_f = JFFS2_INODE_INFO(dir_i);
545 mutex_lock(&dir_f->sem);
546
547 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
548 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
549 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
550 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
551
552 rd->pino = cpu_to_je32(dir_i->i_ino);
553 rd->version = cpu_to_je32(++dir_f->highest_version);
554 rd->ino = cpu_to_je32(inode->i_ino);
555 rd->mctime = cpu_to_je32(JFFS2_NOW());
556 rd->nsize = namelen;
557 rd->type = DT_DIR;
558 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
559 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
560
561 fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
562
563 if (IS_ERR(fd)) {
564 /* dirent failed to write. Delete the inode normally
565 as if it were the final unlink() */
566 jffs2_complete_reservation(c);
567 jffs2_free_raw_dirent(rd);
568 mutex_unlock(&dir_f->sem);
569 ret = PTR_ERR(fd);
570 goto fail;
571 }
572
573 inode_set_mtime_to_ts(dir_i,
574 inode_set_ctime_to_ts(dir_i, ITIME(je32_to_cpu(rd->mctime))));
575 inc_nlink(dir_i);
576
577 jffs2_free_raw_dirent(rd);
578
579 /* Link the fd into the inode's list, obsoleting an old
580 one if necessary. */
581 jffs2_add_fd_to_list(c, fd, &dir_f->dents);
582
583 mutex_unlock(&dir_f->sem);
584 jffs2_complete_reservation(c);
585
586 d_instantiate_new(dentry, inode);
587 return 0;
588
589 fail:
590 iget_failed(inode);
591 return ret;
592}
593
594static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
595{
596 struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
597 struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
598 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(dentry));
599 struct jffs2_full_dirent *fd;
600 int ret;
601 uint32_t now = JFFS2_NOW();
602
603 mutex_lock(&f->sem);
604 for (fd = f->dents ; fd; fd = fd->next) {
605 if (fd->ino) {
606 mutex_unlock(lock: &f->sem);
607 return -ENOTEMPTY;
608 }
609 }
610 mutex_unlock(lock: &f->sem);
611
612 ret = jffs2_do_unlink(c, dir_f, name: dentry->d_name.name,
613 namelen: dentry->d_name.len, dead_f: f, time: now);
614 if (!ret) {
615 inode_set_mtime_to_ts(inode: dir_i,
616 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(now)));
617 clear_nlink(inode: d_inode(dentry));
618 drop_nlink(inode: dir_i);
619 }
620 return ret;
621}
622
623static int jffs2_mknod (struct mnt_idmap *idmap, struct inode *dir_i,
624 struct dentry *dentry, umode_t mode, dev_t rdev)
625{
626 struct jffs2_inode_info *f, *dir_f;
627 struct jffs2_sb_info *c;
628 struct inode *inode;
629 struct jffs2_raw_inode *ri;
630 struct jffs2_raw_dirent *rd;
631 struct jffs2_full_dnode *fn;
632 struct jffs2_full_dirent *fd;
633 int namelen;
634 union jffs2_device_node dev;
635 int devlen = 0;
636 uint32_t alloclen;
637 int ret;
638
639 ri = jffs2_alloc_raw_inode();
640 if (!ri)
641 return -ENOMEM;
642
643 c = JFFS2_SB_INFO(dir_i->i_sb);
644
645 if (S_ISBLK(mode) || S_ISCHR(mode))
646 devlen = jffs2_encode_dev(jdev: &dev, rdev);
647
648 /* Try to reserve enough space for both node and dirent.
649 * Just the node will do for now, though
650 */
651 namelen = dentry->d_name.len;
652 ret = jffs2_reserve_space(c, minsize: sizeof(*ri) + devlen, len: &alloclen,
653 ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
654
655 if (ret) {
656 jffs2_free_raw_inode(ri);
657 return ret;
658 }
659
660 inode = jffs2_new_inode(dir_i, mode, ri);
661
662 if (IS_ERR(ptr: inode)) {
663 jffs2_free_raw_inode(ri);
664 jffs2_complete_reservation(c);
665 return PTR_ERR(ptr: inode);
666 }
667 inode->i_op = &jffs2_file_inode_operations;
668 init_special_inode(inode, inode->i_mode, rdev);
669
670 f = JFFS2_INODE_INFO(inode);
671
672 ri->dsize = ri->csize = cpu_to_je32(devlen);
673 ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
674 ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
675
676 ri->compr = JFFS2_COMPR_NONE;
677 ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
678 ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
679
680 fn = jffs2_write_dnode(c, f, ri, data: (char *)&dev, datalen: devlen, ALLOC_NORMAL);
681
682 jffs2_free_raw_inode(ri);
683
684 if (IS_ERR(ptr: fn)) {
685 /* Eeek. Wave bye bye */
686 mutex_unlock(lock: &f->sem);
687 jffs2_complete_reservation(c);
688 ret = PTR_ERR(ptr: fn);
689 goto fail;
690 }
691 /* No data here. Only a metadata node, which will be
692 obsoleted by the first data write
693 */
694 f->metadata = fn;
695 mutex_unlock(lock: &f->sem);
696
697 jffs2_complete_reservation(c);
698
699 ret = jffs2_init_security(inode, dir: dir_i, qstr: &dentry->d_name);
700 if (ret)
701 goto fail;
702
703 ret = jffs2_init_acl_post(inode);
704 if (ret)
705 goto fail;
706
707 ret = jffs2_reserve_space(c, minsize: sizeof(*rd)+namelen, len: &alloclen,
708 ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
709 if (ret)
710 goto fail;
711
712 rd = jffs2_alloc_raw_dirent();
713 if (!rd) {
714 /* Argh. Now we treat it like a normal delete */
715 jffs2_complete_reservation(c);
716 ret = -ENOMEM;
717 goto fail;
718 }
719
720 dir_f = JFFS2_INODE_INFO(dir_i);
721 mutex_lock(&dir_f->sem);
722
723 rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
724 rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
725 rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
726 rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
727
728 rd->pino = cpu_to_je32(dir_i->i_ino);
729 rd->version = cpu_to_je32(++dir_f->highest_version);
730 rd->ino = cpu_to_je32(inode->i_ino);
731 rd->mctime = cpu_to_je32(JFFS2_NOW());
732 rd->nsize = namelen;
733
734 /* XXX: This is ugly. */
735 rd->type = (mode & S_IFMT) >> 12;
736
737 rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
738 rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
739
740 fd = jffs2_write_dirent(c, f: dir_f, rd, name: dentry->d_name.name, namelen, ALLOC_NORMAL);
741
742 if (IS_ERR(ptr: fd)) {
743 /* dirent failed to write. Delete the inode normally
744 as if it were the final unlink() */
745 jffs2_complete_reservation(c);
746 jffs2_free_raw_dirent(rd);
747 mutex_unlock(lock: &dir_f->sem);
748 ret = PTR_ERR(ptr: fd);
749 goto fail;
750 }
751
752 inode_set_mtime_to_ts(inode: dir_i,
753 ts: inode_set_ctime_to_ts(inode: dir_i, ITIME(je32_to_cpu(rd->mctime))));
754
755 jffs2_free_raw_dirent(rd);
756
757 /* Link the fd into the inode's list, obsoleting an old
758 one if necessary. */
759 jffs2_add_fd_to_list(c, new: fd, list: &dir_f->dents);
760
761 mutex_unlock(lock: &dir_f->sem);
762 jffs2_complete_reservation(c);
763
764 d_instantiate_new(dentry, inode);
765 return 0;
766
767 fail:
768 iget_failed(inode);
769 return ret;
770}
771
772static int jffs2_rename (struct mnt_idmap *idmap,
773 struct inode *old_dir_i, struct dentry *old_dentry,
774 struct inode *new_dir_i, struct dentry *new_dentry,
775 unsigned int flags)
776{
777 int ret;
778 struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
779 struct jffs2_inode_info *victim_f = NULL;
780 uint8_t type;
781 uint32_t now;
782
783 if (flags & ~RENAME_NOREPLACE)
784 return -EINVAL;
785
786 /* The VFS will check for us and prevent trying to rename a
787 * file over a directory and vice versa, but if it's a directory,
788 * the VFS can't check whether the victim is empty. The filesystem
789 * needs to do that for itself.
790 */
791 if (d_really_is_positive(dentry: new_dentry)) {
792 victim_f = JFFS2_INODE_INFO(d_inode(new_dentry));
793 if (d_is_dir(dentry: new_dentry)) {
794 struct jffs2_full_dirent *fd;
795
796 mutex_lock(&victim_f->sem);
797 for (fd = victim_f->dents; fd; fd = fd->next) {
798 if (fd->ino) {
799 mutex_unlock(lock: &victim_f->sem);
800 return -ENOTEMPTY;
801 }
802 }
803 mutex_unlock(lock: &victim_f->sem);
804 }
805 }
806
807 /* XXX: We probably ought to alloc enough space for
808 both nodes at the same time. Writing the new link,
809 then getting -ENOSPC, is quite bad :)
810 */
811
812 /* Make a hard link */
813
814 /* XXX: This is ugly */
815 type = (d_inode(dentry: old_dentry)->i_mode & S_IFMT) >> 12;
816 if (!type) type = DT_REG;
817
818 now = JFFS2_NOW();
819 ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
820 ino: d_inode(dentry: old_dentry)->i_ino, type,
821 name: new_dentry->d_name.name, namelen: new_dentry->d_name.len, time: now);
822
823 if (ret)
824 return ret;
825
826 if (victim_f) {
827 /* There was a victim. Kill it off nicely */
828 if (d_is_dir(dentry: new_dentry))
829 clear_nlink(inode: d_inode(dentry: new_dentry));
830 else
831 drop_nlink(inode: d_inode(dentry: new_dentry));
832 /* Don't oops if the victim was a dirent pointing to an
833 inode which didn't exist. */
834 if (victim_f->inocache) {
835 mutex_lock(&victim_f->sem);
836 if (d_is_dir(dentry: new_dentry))
837 victim_f->inocache->pino_nlink = 0;
838 else
839 victim_f->inocache->pino_nlink--;
840 mutex_unlock(lock: &victim_f->sem);
841 }
842 }
843
844 /* If it was a directory we moved, and there was no victim,
845 increase i_nlink on its new parent */
846 if (d_is_dir(dentry: old_dentry) && !victim_f)
847 inc_nlink(inode: new_dir_i);
848
849 /* Unlink the original */
850 ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
851 name: old_dentry->d_name.name, namelen: old_dentry->d_name.len, NULL, time: now);
852
853 /* We don't touch inode->i_nlink */
854
855 if (ret) {
856 /* Oh shit. We really ought to make a single node which can do both atomically */
857 struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
858 mutex_lock(&f->sem);
859 inc_nlink(inode: d_inode(dentry: old_dentry));
860 if (f->inocache && !d_is_dir(dentry: old_dentry))
861 f->inocache->pino_nlink++;
862 mutex_unlock(lock: &f->sem);
863
864 pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n",
865 __func__, ret);
866 /*
867 * We can't keep the target in dcache after that.
868 * For one thing, we can't afford dentry aliases for directories.
869 * For another, if there was a victim, we _can't_ set new inode
870 * for that sucker and we have to trigger mount eviction - the
871 * caller won't do it on its own since we are returning an error.
872 */
873 d_invalidate(new_dentry);
874 inode_set_mtime_to_ts(inode: new_dir_i,
875 ts: inode_set_ctime_to_ts(inode: new_dir_i, ITIME(now)));
876 return ret;
877 }
878
879 if (d_is_dir(dentry: old_dentry))
880 drop_nlink(inode: old_dir_i);
881
882 inode_set_mtime_to_ts(inode: old_dir_i,
883 ts: inode_set_ctime_to_ts(inode: old_dir_i, ITIME(now)));
884 inode_set_mtime_to_ts(inode: new_dir_i,
885 ts: inode_set_ctime_to_ts(inode: new_dir_i, ITIME(now)));
886
887 return 0;
888}
889
890

source code of linux/fs/jffs2/dir.c