Root/fs/jffs2/dir.c

1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
10 */
11
12#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/fs.h>
15#include <linux/crc32.h>
16#include <linux/jffs2.h>
17#include "jffs2_fs_i.h"
18#include "jffs2_fs_sb.h"
19#include <linux/time.h>
20#include "nodelist.h"
21
22static int jffs2_readdir (struct file *, void *, filldir_t);
23
24static int jffs2_create (struct inode *,struct dentry *,int,
25             struct nameidata *);
26static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
27                    struct nameidata *);
28static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
29static int jffs2_unlink (struct inode *,struct dentry *);
30static int jffs2_symlink (struct inode *,struct dentry *,const char *);
31static int jffs2_mkdir (struct inode *,struct dentry *,int);
32static int jffs2_rmdir (struct inode *,struct dentry *);
33static int jffs2_mknod (struct inode *,struct dentry *,int,dev_t);
34static int jffs2_rename (struct inode *, struct dentry *,
35             struct inode *, struct dentry *);
36
37const struct file_operations jffs2_dir_operations =
38{
39    .read = generic_read_dir,
40    .readdir = jffs2_readdir,
41    .unlocked_ioctl=jffs2_ioctl,
42    .fsync = jffs2_fsync,
43    .llseek = generic_file_llseek,
44};
45
46
47const struct inode_operations jffs2_dir_inode_operations =
48{
49    .create = jffs2_create,
50    .lookup = jffs2_lookup,
51    .link = jffs2_link,
52    .unlink = jffs2_unlink,
53    .symlink = jffs2_symlink,
54    .mkdir = jffs2_mkdir,
55    .rmdir = jffs2_rmdir,
56    .mknod = jffs2_mknod,
57    .rename = jffs2_rename,
58    .permission = jffs2_permission,
59    .setattr = jffs2_setattr,
60    .setxattr = jffs2_setxattr,
61    .getxattr = jffs2_getxattr,
62    .listxattr = jffs2_listxattr,
63    .removexattr = jffs2_removexattr
64};
65
66/***********************************************************************/
67
68
69/* We keep the dirent list sorted in increasing order of name hash,
70   and we use the same hash function as the dentries. Makes this
71   nice and simple
72*/
73static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
74                   struct nameidata *nd)
75{
76    struct jffs2_inode_info *dir_f;
77    struct jffs2_sb_info *c;
78    struct jffs2_full_dirent *fd = NULL, *fd_list;
79    uint32_t ino = 0;
80    struct inode *inode = NULL;
81
82    D1(printk(KERN_DEBUG "jffs2_lookup()\n"));
83
84    if (target->d_name.len > JFFS2_MAX_NAME_LEN)
85        return ERR_PTR(-ENAMETOOLONG);
86
87    dir_f = JFFS2_INODE_INFO(dir_i);
88    c = JFFS2_SB_INFO(dir_i->i_sb);
89
90    mutex_lock(&dir_f->sem);
91
92    /* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
93    for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= target->d_name.hash; fd_list = fd_list->next) {
94        if (fd_list->nhash == target->d_name.hash &&
95            (!fd || fd_list->version > fd->version) &&
96            strlen(fd_list->name) == target->d_name.len &&
97            !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
98            fd = fd_list;
99        }
100    }
101    if (fd)
102        ino = fd->ino;
103    mutex_unlock(&dir_f->sem);
104    if (ino) {
105        inode = jffs2_iget(dir_i->i_sb, ino);
106        if (IS_ERR(inode)) {
107            printk(KERN_WARNING "iget() failed for ino #%u\n", ino);
108            return ERR_CAST(inode);
109        }
110    }
111
112    return d_splice_alias(inode, target);
113}
114
115/***********************************************************************/
116
117
118static int jffs2_readdir(struct file *filp, void *dirent, filldir_t filldir)
119{
120    struct jffs2_inode_info *f;
121    struct jffs2_sb_info *c;
122    struct inode *inode = filp->f_path.dentry->d_inode;
123    struct jffs2_full_dirent *fd;
124    unsigned long offset, curofs;
125
126    D1(printk(KERN_DEBUG "jffs2_readdir() for dir_i #%lu\n", filp->f_path.dentry->d_inode->i_ino));
127
128    f = JFFS2_INODE_INFO(inode);
129    c = JFFS2_SB_INFO(inode->i_sb);
130
131    offset = filp->f_pos;
132
133    if (offset == 0) {
134        D1(printk(KERN_DEBUG "Dirent 0: \".\", ino #%lu\n", inode->i_ino));
135        if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
136            goto out;
137        offset++;
138    }
139    if (offset == 1) {
140        unsigned long pino = parent_ino(filp->f_path.dentry);
141        D1(printk(KERN_DEBUG "Dirent 1: \"..\", ino #%lu\n", pino));
142        if (filldir(dirent, "..", 2, 1, pino, DT_DIR) < 0)
143            goto out;
144        offset++;
145    }
146
147    curofs=1;
148    mutex_lock(&f->sem);
149    for (fd = f->dents; fd; fd = fd->next) {
150
151        curofs++;
152        /* First loop: curofs = 2; offset = 2 */
153        if (curofs < offset) {
154            D2(printk(KERN_DEBUG "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
155                  fd->name, fd->ino, fd->type, curofs, offset));
156            continue;
157        }
158        if (!fd->ino) {
159            D2(printk(KERN_DEBUG "Skipping deletion dirent \"%s\"\n", fd->name));
160            offset++;
161            continue;
162        }
163        D2(printk(KERN_DEBUG "Dirent %ld: \"%s\", ino #%u, type %d\n", offset, fd->name, fd->ino, fd->type));
164        if (filldir(dirent, fd->name, strlen(fd->name), offset, fd->ino, fd->type) < 0)
165            break;
166        offset++;
167    }
168    mutex_unlock(&f->sem);
169 out:
170    filp->f_pos = offset;
171    return 0;
172}
173
174/***********************************************************************/
175
176
177static int jffs2_create(struct inode *dir_i, struct dentry *dentry, int mode,
178            struct nameidata *nd)
179{
180    struct jffs2_raw_inode *ri;
181    struct jffs2_inode_info *f, *dir_f;
182    struct jffs2_sb_info *c;
183    struct inode *inode;
184    int ret;
185
186    ri = jffs2_alloc_raw_inode();
187    if (!ri)
188        return -ENOMEM;
189
190    c = JFFS2_SB_INFO(dir_i->i_sb);
191
192    D1(printk(KERN_DEBUG "jffs2_create()\n"));
193
194    inode = jffs2_new_inode(dir_i, mode, ri);
195
196    if (IS_ERR(inode)) {
197        D1(printk(KERN_DEBUG "jffs2_new_inode() failed\n"));
198        jffs2_free_raw_inode(ri);
199        return PTR_ERR(inode);
200    }
201
202    inode->i_op = &jffs2_file_inode_operations;
203    inode->i_fop = &jffs2_file_operations;
204    inode->i_mapping->a_ops = &jffs2_file_address_operations;
205    inode->i_mapping->nrpages = 0;
206
207    f = JFFS2_INODE_INFO(inode);
208    dir_f = JFFS2_INODE_INFO(dir_i);
209
210    /* jffs2_do_create() will want to lock it, _after_ reserving
211       space and taking c-alloc_sem. If we keep it locked here,
212       lockdep gets unhappy (although it's a false positive;
213       nothing else will be looking at this inode yet so there's
214       no chance of AB-BA deadlock involving its f->sem). */
215    mutex_unlock(&f->sem);
216
217    ret = jffs2_do_create(c, dir_f, f, ri,
218                  dentry->d_name.name, dentry->d_name.len);
219    if (ret)
220        goto fail;
221
222    dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
223
224    jffs2_free_raw_inode(ri);
225    d_instantiate(dentry, inode);
226
227    D1(printk(KERN_DEBUG "jffs2_create: Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
228          inode->i_ino, inode->i_mode, inode->i_nlink,
229          f->inocache->pino_nlink, inode->i_mapping->nrpages));
230    return 0;
231
232 fail:
233    make_bad_inode(inode);
234    iput(inode);
235    jffs2_free_raw_inode(ri);
236    return ret;
237}
238
239/***********************************************************************/
240
241
242static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
243{
244    struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
245    struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
246    struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(dentry->d_inode);
247    int ret;
248    uint32_t now = get_seconds();
249
250    ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
251                  dentry->d_name.len, dead_f, now);
252    if (dead_f->inocache)
253        dentry->d_inode->i_nlink = dead_f->inocache->pino_nlink;
254    if (!ret)
255        dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
256    return ret;
257}
258/***********************************************************************/
259
260
261static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
262{
263    struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_inode->i_sb);
264    struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
265    struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
266    int ret;
267    uint8_t type;
268    uint32_t now;
269
270    /* Don't let people make hard links to bad inodes. */
271    if (!f->inocache)
272        return -EIO;
273
274    if (S_ISDIR(old_dentry->d_inode->i_mode))
275        return -EPERM;
276
277    /* XXX: This is ugly */
278    type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
279    if (!type) type = DT_REG;
280
281    now = get_seconds();
282    ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now);
283
284    if (!ret) {
285        mutex_lock(&f->sem);
286        old_dentry->d_inode->i_nlink = ++f->inocache->pino_nlink;
287        mutex_unlock(&f->sem);
288        d_instantiate(dentry, old_dentry->d_inode);
289        dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
290        atomic_inc(&old_dentry->d_inode->i_count);
291    }
292    return ret;
293}
294
295/***********************************************************************/
296
297static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char *target)
298{
299    struct jffs2_inode_info *f, *dir_f;
300    struct jffs2_sb_info *c;
301    struct inode *inode;
302    struct jffs2_raw_inode *ri;
303    struct jffs2_raw_dirent *rd;
304    struct jffs2_full_dnode *fn;
305    struct jffs2_full_dirent *fd;
306    int namelen;
307    uint32_t alloclen;
308    int ret, targetlen = strlen(target);
309
310    /* FIXME: If you care. We'd need to use frags for the target
311       if it grows much more than this */
312    if (targetlen > 254)
313        return -ENAMETOOLONG;
314
315    ri = jffs2_alloc_raw_inode();
316
317    if (!ri)
318        return -ENOMEM;
319
320    c = JFFS2_SB_INFO(dir_i->i_sb);
321
322    /* Try to reserve enough space for both node and dirent.
323     * Just the node will do for now, though
324     */
325    namelen = dentry->d_name.len;
326    ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
327                  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
328
329    if (ret) {
330        jffs2_free_raw_inode(ri);
331        return ret;
332    }
333
334    inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
335
336    if (IS_ERR(inode)) {
337        jffs2_free_raw_inode(ri);
338        jffs2_complete_reservation(c);
339        return PTR_ERR(inode);
340    }
341
342    inode->i_op = &jffs2_symlink_inode_operations;
343
344    f = JFFS2_INODE_INFO(inode);
345
346    inode->i_size = targetlen;
347    ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
348    ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
349    ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
350
351    ri->compr = JFFS2_COMPR_NONE;
352    ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
353    ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
354
355    fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL);
356
357    jffs2_free_raw_inode(ri);
358
359    if (IS_ERR(fn)) {
360        /* Eeek. Wave bye bye */
361        mutex_unlock(&f->sem);
362        jffs2_complete_reservation(c);
363        jffs2_clear_inode(inode);
364        return PTR_ERR(fn);
365    }
366
367    /* We use f->target field to store the target path. */
368    f->target = kmalloc(targetlen + 1, GFP_KERNEL);
369    if (!f->target) {
370        printk(KERN_WARNING "Can't allocate %d bytes of memory\n", targetlen + 1);
371        mutex_unlock(&f->sem);
372        jffs2_complete_reservation(c);
373        jffs2_clear_inode(inode);
374        return -ENOMEM;
375    }
376
377    memcpy(f->target, target, targetlen + 1);
378    D1(printk(KERN_DEBUG "jffs2_symlink: symlink's target '%s' cached\n", (char *)f->target));
379
380    /* No data here. Only a metadata node, which will be
381       obsoleted by the first data write
382    */
383    f->metadata = fn;
384    mutex_unlock(&f->sem);
385
386    jffs2_complete_reservation(c);
387
388    ret = jffs2_init_security(inode, dir_i);
389    if (ret) {
390        jffs2_clear_inode(inode);
391        return ret;
392    }
393    ret = jffs2_init_acl_post(inode);
394    if (ret) {
395        jffs2_clear_inode(inode);
396        return ret;
397    }
398
399    ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
400                  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
401    if (ret) {
402        /* Eep. */
403        jffs2_clear_inode(inode);
404        return ret;
405    }
406
407    rd = jffs2_alloc_raw_dirent();
408    if (!rd) {
409        /* Argh. Now we treat it like a normal delete */
410        jffs2_complete_reservation(c);
411        jffs2_clear_inode(inode);
412        return -ENOMEM;
413    }
414
415    dir_f = JFFS2_INODE_INFO(dir_i);
416    mutex_lock(&dir_f->sem);
417
418    rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
419    rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
420    rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
421    rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
422
423    rd->pino = cpu_to_je32(dir_i->i_ino);
424    rd->version = cpu_to_je32(++dir_f->highest_version);
425    rd->ino = cpu_to_je32(inode->i_ino);
426    rd->mctime = cpu_to_je32(get_seconds());
427    rd->nsize = namelen;
428    rd->type = DT_LNK;
429    rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
430    rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
431
432    fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
433
434    if (IS_ERR(fd)) {
435        /* dirent failed to write. Delete the inode normally
436           as if it were the final unlink() */
437        jffs2_complete_reservation(c);
438        jffs2_free_raw_dirent(rd);
439        mutex_unlock(&dir_f->sem);
440        jffs2_clear_inode(inode);
441        return PTR_ERR(fd);
442    }
443
444    dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
445
446    jffs2_free_raw_dirent(rd);
447
448    /* Link the fd into the inode's list, obsoleting an old
449       one if necessary. */
450    jffs2_add_fd_to_list(c, fd, &dir_f->dents);
451
452    mutex_unlock(&dir_f->sem);
453    jffs2_complete_reservation(c);
454
455    d_instantiate(dentry, inode);
456    return 0;
457}
458
459
460static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode)
461{
462    struct jffs2_inode_info *f, *dir_f;
463    struct jffs2_sb_info *c;
464    struct inode *inode;
465    struct jffs2_raw_inode *ri;
466    struct jffs2_raw_dirent *rd;
467    struct jffs2_full_dnode *fn;
468    struct jffs2_full_dirent *fd;
469    int namelen;
470    uint32_t alloclen;
471    int ret;
472
473    mode |= S_IFDIR;
474
475    ri = jffs2_alloc_raw_inode();
476    if (!ri)
477        return -ENOMEM;
478
479    c = JFFS2_SB_INFO(dir_i->i_sb);
480
481    /* Try to reserve enough space for both node and dirent.
482     * Just the node will do for now, though
483     */
484    namelen = dentry->d_name.len;
485    ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
486                  JFFS2_SUMMARY_INODE_SIZE);
487
488    if (ret) {
489        jffs2_free_raw_inode(ri);
490        return ret;
491    }
492
493    inode = jffs2_new_inode(dir_i, mode, ri);
494
495    if (IS_ERR(inode)) {
496        jffs2_free_raw_inode(ri);
497        jffs2_complete_reservation(c);
498        return PTR_ERR(inode);
499    }
500
501    inode->i_op = &jffs2_dir_inode_operations;
502    inode->i_fop = &jffs2_dir_operations;
503
504    f = JFFS2_INODE_INFO(inode);
505
506    /* Directories get nlink 2 at start */
507    inode->i_nlink = 2;
508    /* but ic->pino_nlink is the parent ino# */
509    f->inocache->pino_nlink = dir_i->i_ino;
510
511    ri->data_crc = cpu_to_je32(0);
512    ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
513
514    fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
515
516    jffs2_free_raw_inode(ri);
517
518    if (IS_ERR(fn)) {
519        /* Eeek. Wave bye bye */
520        mutex_unlock(&f->sem);
521        jffs2_complete_reservation(c);
522        jffs2_clear_inode(inode);
523        return PTR_ERR(fn);
524    }
525    /* No data here. Only a metadata node, which will be
526       obsoleted by the first data write
527    */
528    f->metadata = fn;
529    mutex_unlock(&f->sem);
530
531    jffs2_complete_reservation(c);
532
533    ret = jffs2_init_security(inode, dir_i);
534    if (ret) {
535        jffs2_clear_inode(inode);
536        return ret;
537    }
538    ret = jffs2_init_acl_post(inode);
539    if (ret) {
540        jffs2_clear_inode(inode);
541        return ret;
542    }
543
544    ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
545                  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
546    if (ret) {
547        /* Eep. */
548        jffs2_clear_inode(inode);
549        return ret;
550    }
551
552    rd = jffs2_alloc_raw_dirent();
553    if (!rd) {
554        /* Argh. Now we treat it like a normal delete */
555        jffs2_complete_reservation(c);
556        jffs2_clear_inode(inode);
557        return -ENOMEM;
558    }
559
560    dir_f = JFFS2_INODE_INFO(dir_i);
561    mutex_lock(&dir_f->sem);
562
563    rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
564    rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
565    rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
566    rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
567
568    rd->pino = cpu_to_je32(dir_i->i_ino);
569    rd->version = cpu_to_je32(++dir_f->highest_version);
570    rd->ino = cpu_to_je32(inode->i_ino);
571    rd->mctime = cpu_to_je32(get_seconds());
572    rd->nsize = namelen;
573    rd->type = DT_DIR;
574    rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
575    rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
576
577    fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
578
579    if (IS_ERR(fd)) {
580        /* dirent failed to write. Delete the inode normally
581           as if it were the final unlink() */
582        jffs2_complete_reservation(c);
583        jffs2_free_raw_dirent(rd);
584        mutex_unlock(&dir_f->sem);
585        jffs2_clear_inode(inode);
586        return PTR_ERR(fd);
587    }
588
589    dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
590    inc_nlink(dir_i);
591
592    jffs2_free_raw_dirent(rd);
593
594    /* Link the fd into the inode's list, obsoleting an old
595       one if necessary. */
596    jffs2_add_fd_to_list(c, fd, &dir_f->dents);
597
598    mutex_unlock(&dir_f->sem);
599    jffs2_complete_reservation(c);
600
601    d_instantiate(dentry, inode);
602    return 0;
603}
604
605static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
606{
607    struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
608    struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
609    struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);
610    struct jffs2_full_dirent *fd;
611    int ret;
612    uint32_t now = get_seconds();
613
614    for (fd = f->dents ; fd; fd = fd->next) {
615        if (fd->ino)
616            return -ENOTEMPTY;
617    }
618
619    ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
620                  dentry->d_name.len, f, now);
621    if (!ret) {
622        dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
623        clear_nlink(dentry->d_inode);
624        drop_nlink(dir_i);
625    }
626    return ret;
627}
628
629static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, dev_t rdev)
630{
631    struct jffs2_inode_info *f, *dir_f;
632    struct jffs2_sb_info *c;
633    struct inode *inode;
634    struct jffs2_raw_inode *ri;
635    struct jffs2_raw_dirent *rd;
636    struct jffs2_full_dnode *fn;
637    struct jffs2_full_dirent *fd;
638    int namelen;
639    union jffs2_device_node dev;
640    int devlen = 0;
641    uint32_t alloclen;
642    int ret;
643
644    if (!new_valid_dev(rdev))
645        return -EINVAL;
646
647    ri = jffs2_alloc_raw_inode();
648    if (!ri)
649        return -ENOMEM;
650
651    c = JFFS2_SB_INFO(dir_i->i_sb);
652
653    if (S_ISBLK(mode) || S_ISCHR(mode))
654        devlen = jffs2_encode_dev(&dev, rdev);
655
656    /* Try to reserve enough space for both node and dirent.
657     * Just the node will do for now, though
658     */
659    namelen = dentry->d_name.len;
660    ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
661                  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
662
663    if (ret) {
664        jffs2_free_raw_inode(ri);
665        return ret;
666    }
667
668    inode = jffs2_new_inode(dir_i, mode, ri);
669
670    if (IS_ERR(inode)) {
671        jffs2_free_raw_inode(ri);
672        jffs2_complete_reservation(c);
673        return PTR_ERR(inode);
674    }
675    inode->i_op = &jffs2_file_inode_operations;
676    init_special_inode(inode, inode->i_mode, rdev);
677
678    f = JFFS2_INODE_INFO(inode);
679
680    ri->dsize = ri->csize = cpu_to_je32(devlen);
681    ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
682    ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
683
684    ri->compr = JFFS2_COMPR_NONE;
685    ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
686    ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
687
688    fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL);
689
690    jffs2_free_raw_inode(ri);
691
692    if (IS_ERR(fn)) {
693        /* Eeek. Wave bye bye */
694        mutex_unlock(&f->sem);
695        jffs2_complete_reservation(c);
696        jffs2_clear_inode(inode);
697        return PTR_ERR(fn);
698    }
699    /* No data here. Only a metadata node, which will be
700       obsoleted by the first data write
701    */
702    f->metadata = fn;
703    mutex_unlock(&f->sem);
704
705    jffs2_complete_reservation(c);
706
707    ret = jffs2_init_security(inode, dir_i);
708    if (ret) {
709        jffs2_clear_inode(inode);
710        return ret;
711    }
712    ret = jffs2_init_acl_post(inode);
713    if (ret) {
714        jffs2_clear_inode(inode);
715        return ret;
716    }
717
718    ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
719                  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
720    if (ret) {
721        /* Eep. */
722        jffs2_clear_inode(inode);
723        return ret;
724    }
725
726    rd = jffs2_alloc_raw_dirent();
727    if (!rd) {
728        /* Argh. Now we treat it like a normal delete */
729        jffs2_complete_reservation(c);
730        jffs2_clear_inode(inode);
731        return -ENOMEM;
732    }
733
734    dir_f = JFFS2_INODE_INFO(dir_i);
735    mutex_lock(&dir_f->sem);
736
737    rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
738    rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
739    rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
740    rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
741
742    rd->pino = cpu_to_je32(dir_i->i_ino);
743    rd->version = cpu_to_je32(++dir_f->highest_version);
744    rd->ino = cpu_to_je32(inode->i_ino);
745    rd->mctime = cpu_to_je32(get_seconds());
746    rd->nsize = namelen;
747
748    /* XXX: This is ugly. */
749    rd->type = (mode & S_IFMT) >> 12;
750
751    rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
752    rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
753
754    fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
755
756    if (IS_ERR(fd)) {
757        /* dirent failed to write. Delete the inode normally
758           as if it were the final unlink() */
759        jffs2_complete_reservation(c);
760        jffs2_free_raw_dirent(rd);
761        mutex_unlock(&dir_f->sem);
762        jffs2_clear_inode(inode);
763        return PTR_ERR(fd);
764    }
765
766    dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
767
768    jffs2_free_raw_dirent(rd);
769
770    /* Link the fd into the inode's list, obsoleting an old
771       one if necessary. */
772    jffs2_add_fd_to_list(c, fd, &dir_f->dents);
773
774    mutex_unlock(&dir_f->sem);
775    jffs2_complete_reservation(c);
776
777    d_instantiate(dentry, inode);
778
779    return 0;
780}
781
782static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
783             struct inode *new_dir_i, struct dentry *new_dentry)
784{
785    int ret;
786    struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
787    struct jffs2_inode_info *victim_f = NULL;
788    uint8_t type;
789    uint32_t now;
790
791    /* The VFS will check for us and prevent trying to rename a
792     * file over a directory and vice versa, but if it's a directory,
793     * the VFS can't check whether the victim is empty. The filesystem
794     * needs to do that for itself.
795     */
796    if (new_dentry->d_inode) {
797        victim_f = JFFS2_INODE_INFO(new_dentry->d_inode);
798        if (S_ISDIR(new_dentry->d_inode->i_mode)) {
799            struct jffs2_full_dirent *fd;
800
801            mutex_lock(&victim_f->sem);
802            for (fd = victim_f->dents; fd; fd = fd->next) {
803                if (fd->ino) {
804                    mutex_unlock(&victim_f->sem);
805                    return -ENOTEMPTY;
806                }
807            }
808            mutex_unlock(&victim_f->sem);
809        }
810    }
811
812    /* XXX: We probably ought to alloc enough space for
813       both nodes at the same time. Writing the new link,
814       then getting -ENOSPC, is quite bad :)
815    */
816
817    /* Make a hard link */
818
819    /* XXX: This is ugly */
820    type = (old_dentry->d_inode->i_mode & S_IFMT) >> 12;
821    if (!type) type = DT_REG;
822
823    now = get_seconds();
824    ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
825                old_dentry->d_inode->i_ino, type,
826                new_dentry->d_name.name, new_dentry->d_name.len, now);
827
828    if (ret)
829        return ret;
830
831    if (victim_f) {
832        /* There was a victim. Kill it off nicely */
833        drop_nlink(new_dentry->d_inode);
834        /* Don't oops if the victim was a dirent pointing to an
835           inode which didn't exist. */
836        if (victim_f->inocache) {
837            mutex_lock(&victim_f->sem);
838            if (S_ISDIR(new_dentry->d_inode->i_mode))
839                victim_f->inocache->pino_nlink = 0;
840            else
841                victim_f->inocache->pino_nlink--;
842            mutex_unlock(&victim_f->sem);
843        }
844    }
845
846    /* If it was a directory we moved, and there was no victim,
847       increase i_nlink on its new parent */
848    if (S_ISDIR(old_dentry->d_inode->i_mode) && !victim_f)
849        inc_nlink(new_dir_i);
850
851    /* Unlink the original */
852    ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
853                  old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
854
855    /* We don't touch inode->i_nlink */
856
857    if (ret) {
858        /* Oh shit. We really ought to make a single node which can do both atomically */
859        struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode);
860        mutex_lock(&f->sem);
861        inc_nlink(old_dentry->d_inode);
862        if (f->inocache && !S_ISDIR(old_dentry->d_inode->i_mode))
863            f->inocache->pino_nlink++;
864        mutex_unlock(&f->sem);
865
866        printk(KERN_NOTICE "jffs2_rename(): Link succeeded, unlink failed (err %d). You now have a hard link\n", ret);
867        /* Might as well let the VFS know */
868        d_instantiate(new_dentry, old_dentry->d_inode);
869        atomic_inc(&old_dentry->d_inode->i_count);
870        new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
871        return ret;
872    }
873
874    if (S_ISDIR(old_dentry->d_inode->i_mode))
875        drop_nlink(old_dir_i);
876
877    new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now);
878
879    return 0;
880}
881
882

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