Merge branch 'for-2.6.27' of git://git.marvell.com/mv643xx_eth into upstream-fixes
[linux-2.6] / drivers / mtd / ubi / cdev.c
1 /*
2  * Copyright (c) International Business Machines Corp., 2006
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12  * the 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 to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  *
18  * Author: Artem Bityutskiy (Битюцкий Артём)
19  */
20
21 /*
22  * This file includes implementation of UBI character device operations.
23  *
24  * There are two kinds of character devices in UBI: UBI character devices and
25  * UBI volume character devices. UBI character devices allow users to
26  * manipulate whole volumes: create, remove, and re-size them. Volume character
27  * devices provide volume I/O capabilities.
28  *
29  * Major and minor numbers are assigned dynamically to both UBI and volume
30  * character devices.
31  *
32  * Well, there is the third kind of character devices - the UBI control
33  * character device, which allows to manipulate by UBI devices - create and
34  * delete them. In other words, it is used for attaching and detaching MTD
35  * devices.
36  */
37
38 #include <linux/module.h>
39 #include <linux/stat.h>
40 #include <linux/ioctl.h>
41 #include <linux/capability.h>
42 #include <linux/uaccess.h>
43 #include <linux/smp_lock.h>
44 #include <mtd/ubi-user.h>
45 #include <asm/div64.h>
46 #include "ubi.h"
47
48 /**
49  * get_exclusive - get exclusive access to an UBI volume.
50  * @desc: volume descriptor
51  *
52  * This function changes UBI volume open mode to "exclusive". Returns previous
53  * mode value (positive integer) in case of success and a negative error code
54  * in case of failure.
55  */
56 static int get_exclusive(struct ubi_volume_desc *desc)
57 {
58         int users, err;
59         struct ubi_volume *vol = desc->vol;
60
61         spin_lock(&vol->ubi->volumes_lock);
62         users = vol->readers + vol->writers + vol->exclusive;
63         ubi_assert(users > 0);
64         if (users > 1) {
65                 dbg_err("%d users for volume %d", users, vol->vol_id);
66                 err = -EBUSY;
67         } else {
68                 vol->readers = vol->writers = 0;
69                 vol->exclusive = 1;
70                 err = desc->mode;
71                 desc->mode = UBI_EXCLUSIVE;
72         }
73         spin_unlock(&vol->ubi->volumes_lock);
74
75         return err;
76 }
77
78 /**
79  * revoke_exclusive - revoke exclusive mode.
80  * @desc: volume descriptor
81  * @mode: new mode to switch to
82  */
83 static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
84 {
85         struct ubi_volume *vol = desc->vol;
86
87         spin_lock(&vol->ubi->volumes_lock);
88         ubi_assert(vol->readers == 0 && vol->writers == 0);
89         ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
90         vol->exclusive = 0;
91         if (mode == UBI_READONLY)
92                 vol->readers = 1;
93         else if (mode == UBI_READWRITE)
94                 vol->writers = 1;
95         else
96                 vol->exclusive = 1;
97         spin_unlock(&vol->ubi->volumes_lock);
98
99         desc->mode = mode;
100 }
101
102 static int vol_cdev_open(struct inode *inode, struct file *file)
103 {
104         struct ubi_volume_desc *desc;
105         int vol_id = iminor(inode) - 1, mode, ubi_num;
106
107         lock_kernel();
108         ubi_num = ubi_major2num(imajor(inode));
109         if (ubi_num < 0) {
110                 unlock_kernel();
111                 return ubi_num;
112         }
113
114         if (file->f_mode & FMODE_WRITE)
115                 mode = UBI_READWRITE;
116         else
117                 mode = UBI_READONLY;
118
119         dbg_gen("open volume %d, mode %d", vol_id, mode);
120
121         desc = ubi_open_volume(ubi_num, vol_id, mode);
122         unlock_kernel();
123         if (IS_ERR(desc))
124                 return PTR_ERR(desc);
125
126         file->private_data = desc;
127         return 0;
128 }
129
130 static int vol_cdev_release(struct inode *inode, struct file *file)
131 {
132         struct ubi_volume_desc *desc = file->private_data;
133         struct ubi_volume *vol = desc->vol;
134
135         dbg_gen("release volume %d, mode %d", vol->vol_id, desc->mode);
136
137         if (vol->updating) {
138                 ubi_warn("update of volume %d not finished, volume is damaged",
139                          vol->vol_id);
140                 ubi_assert(!vol->changing_leb);
141                 vol->updating = 0;
142                 vfree(vol->upd_buf);
143         } else if (vol->changing_leb) {
144                 dbg_gen("only %lld of %lld bytes received for atomic LEB change"
145                         " for volume %d:%d, cancel", vol->upd_received,
146                         vol->upd_bytes, vol->ubi->ubi_num, vol->vol_id);
147                 vol->changing_leb = 0;
148                 vfree(vol->upd_buf);
149         }
150
151         ubi_close_volume(desc);
152         return 0;
153 }
154
155 static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin)
156 {
157         struct ubi_volume_desc *desc = file->private_data;
158         struct ubi_volume *vol = desc->vol;
159         loff_t new_offset;
160
161         if (vol->updating) {
162                  /* Update is in progress, seeking is prohibited */
163                 dbg_err("updating");
164                 return -EBUSY;
165         }
166
167         switch (origin) {
168         case 0: /* SEEK_SET */
169                 new_offset = offset;
170                 break;
171         case 1: /* SEEK_CUR */
172                 new_offset = file->f_pos + offset;
173                 break;
174         case 2: /* SEEK_END */
175                 new_offset = vol->used_bytes + offset;
176                 break;
177         default:
178                 return -EINVAL;
179         }
180
181         if (new_offset < 0 || new_offset > vol->used_bytes) {
182                 dbg_err("bad seek %lld", new_offset);
183                 return -EINVAL;
184         }
185
186         dbg_gen("seek volume %d, offset %lld, origin %d, new offset %lld",
187                 vol->vol_id, offset, origin, new_offset);
188
189         file->f_pos = new_offset;
190         return new_offset;
191 }
192
193 static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count,
194                              loff_t *offp)
195 {
196         struct ubi_volume_desc *desc = file->private_data;
197         struct ubi_volume *vol = desc->vol;
198         struct ubi_device *ubi = vol->ubi;
199         int err, lnum, off, len,  tbuf_size;
200         size_t count_save = count;
201         void *tbuf;
202         uint64_t tmp;
203
204         dbg_gen("read %zd bytes from offset %lld of volume %d",
205                 count, *offp, vol->vol_id);
206
207         if (vol->updating) {
208                 dbg_err("updating");
209                 return -EBUSY;
210         }
211         if (vol->upd_marker) {
212                 dbg_err("damaged volume, update marker is set");
213                 return -EBADF;
214         }
215         if (*offp == vol->used_bytes || count == 0)
216                 return 0;
217
218         if (vol->corrupted)
219                 dbg_gen("read from corrupted volume %d", vol->vol_id);
220
221         if (*offp + count > vol->used_bytes)
222                 count_save = count = vol->used_bytes - *offp;
223
224         tbuf_size = vol->usable_leb_size;
225         if (count < tbuf_size)
226                 tbuf_size = ALIGN(count, ubi->min_io_size);
227         tbuf = vmalloc(tbuf_size);
228         if (!tbuf)
229                 return -ENOMEM;
230
231         len = count > tbuf_size ? tbuf_size : count;
232
233         tmp = *offp;
234         off = do_div(tmp, vol->usable_leb_size);
235         lnum = tmp;
236
237         do {
238                 cond_resched();
239
240                 if (off + len >= vol->usable_leb_size)
241                         len = vol->usable_leb_size - off;
242
243                 err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0);
244                 if (err)
245                         break;
246
247                 off += len;
248                 if (off == vol->usable_leb_size) {
249                         lnum += 1;
250                         off -= vol->usable_leb_size;
251                 }
252
253                 count -= len;
254                 *offp += len;
255
256                 err = copy_to_user(buf, tbuf, len);
257                 if (err) {
258                         err = -EFAULT;
259                         break;
260                 }
261
262                 buf += len;
263                 len = count > tbuf_size ? tbuf_size : count;
264         } while (count);
265
266         vfree(tbuf);
267         return err ? err : count_save - count;
268 }
269
270 #ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
271
272 /*
273  * This function allows to directly write to dynamic UBI volumes, without
274  * issuing the volume update operation. Available only as a debugging feature.
275  * Very useful for testing UBI.
276  */
277 static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf,
278                                      size_t count, loff_t *offp)
279 {
280         struct ubi_volume_desc *desc = file->private_data;
281         struct ubi_volume *vol = desc->vol;
282         struct ubi_device *ubi = vol->ubi;
283         int lnum, off, len, tbuf_size, err = 0;
284         size_t count_save = count;
285         char *tbuf;
286         uint64_t tmp;
287
288         dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
289                 count, *offp, vol->vol_id);
290
291         if (vol->vol_type == UBI_STATIC_VOLUME)
292                 return -EROFS;
293
294         tmp = *offp;
295         off = do_div(tmp, vol->usable_leb_size);
296         lnum = tmp;
297
298         if (off & (ubi->min_io_size - 1)) {
299                 dbg_err("unaligned position");
300                 return -EINVAL;
301         }
302
303         if (*offp + count > vol->used_bytes)
304                 count_save = count = vol->used_bytes - *offp;
305
306         /* We can write only in fractions of the minimum I/O unit */
307         if (count & (ubi->min_io_size - 1)) {
308                 dbg_err("unaligned write length");
309                 return -EINVAL;
310         }
311
312         tbuf_size = vol->usable_leb_size;
313         if (count < tbuf_size)
314                 tbuf_size = ALIGN(count, ubi->min_io_size);
315         tbuf = vmalloc(tbuf_size);
316         if (!tbuf)
317                 return -ENOMEM;
318
319         len = count > tbuf_size ? tbuf_size : count;
320
321         while (count) {
322                 cond_resched();
323
324                 if (off + len >= vol->usable_leb_size)
325                         len = vol->usable_leb_size - off;
326
327                 err = copy_from_user(tbuf, buf, len);
328                 if (err) {
329                         err = -EFAULT;
330                         break;
331                 }
332
333                 err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len,
334                                         UBI_UNKNOWN);
335                 if (err)
336                         break;
337
338                 off += len;
339                 if (off == vol->usable_leb_size) {
340                         lnum += 1;
341                         off -= vol->usable_leb_size;
342                 }
343
344                 count -= len;
345                 *offp += len;
346                 buf += len;
347                 len = count > tbuf_size ? tbuf_size : count;
348         }
349
350         vfree(tbuf);
351         return err ? err : count_save - count;
352 }
353
354 #else
355 #define vol_cdev_direct_write(file, buf, count, offp) (-EPERM)
356 #endif /* CONFIG_MTD_UBI_DEBUG_USERSPACE_IO */
357
358 static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
359                               size_t count, loff_t *offp)
360 {
361         int err = 0;
362         struct ubi_volume_desc *desc = file->private_data;
363         struct ubi_volume *vol = desc->vol;
364         struct ubi_device *ubi = vol->ubi;
365
366         if (!vol->updating && !vol->changing_leb)
367                 return vol_cdev_direct_write(file, buf, count, offp);
368
369         if (vol->updating)
370                 err = ubi_more_update_data(ubi, vol, buf, count);
371         else
372                 err = ubi_more_leb_change_data(ubi, vol, buf, count);
373
374         if (err < 0) {
375                 ubi_err("cannot accept more %zd bytes of data, error %d",
376                         count, err);
377                 return err;
378         }
379
380         if (err) {
381                 /*
382                  * The operation is finished, @err contains number of actually
383                  * written bytes.
384                  */
385                 count = err;
386
387                 if (vol->changing_leb) {
388                         revoke_exclusive(desc, UBI_READWRITE);
389                         return count;
390                 }
391
392                 err = ubi_check_volume(ubi, vol->vol_id);
393                 if (err < 0)
394                         return err;
395
396                 if (err) {
397                         ubi_warn("volume %d on UBI device %d is corrupted",
398                                  vol->vol_id, ubi->ubi_num);
399                         vol->corrupted = 1;
400                 }
401                 vol->checked = 1;
402                 ubi_gluebi_updated(vol);
403                 revoke_exclusive(desc, UBI_READWRITE);
404         }
405
406         return count;
407 }
408
409 static int vol_cdev_ioctl(struct inode *inode, struct file *file,
410                           unsigned int cmd, unsigned long arg)
411 {
412         int err = 0;
413         struct ubi_volume_desc *desc = file->private_data;
414         struct ubi_volume *vol = desc->vol;
415         struct ubi_device *ubi = vol->ubi;
416         void __user *argp = (void __user *)arg;
417
418         switch (cmd) {
419         /* Volume update command */
420         case UBI_IOCVOLUP:
421         {
422                 int64_t bytes, rsvd_bytes;
423
424                 if (!capable(CAP_SYS_RESOURCE)) {
425                         err = -EPERM;
426                         break;
427                 }
428
429                 err = copy_from_user(&bytes, argp, sizeof(int64_t));
430                 if (err) {
431                         err = -EFAULT;
432                         break;
433                 }
434
435                 if (desc->mode == UBI_READONLY) {
436                         err = -EROFS;
437                         break;
438                 }
439
440                 rsvd_bytes = (long long)vol->reserved_pebs *
441                                         ubi->leb_size-vol->data_pad;
442                 if (bytes < 0 || bytes > rsvd_bytes) {
443                         err = -EINVAL;
444                         break;
445                 }
446
447                 err = get_exclusive(desc);
448                 if (err < 0)
449                         break;
450
451                 err = ubi_start_update(ubi, vol, bytes);
452                 if (bytes == 0)
453                         revoke_exclusive(desc, UBI_READWRITE);
454                 break;
455         }
456
457         /* Atomic logical eraseblock change command */
458         case UBI_IOCEBCH:
459         {
460                 struct ubi_leb_change_req req;
461
462                 err = copy_from_user(&req, argp,
463                                      sizeof(struct ubi_leb_change_req));
464                 if (err) {
465                         err = -EFAULT;
466                         break;
467                 }
468
469                 if (desc->mode == UBI_READONLY ||
470                     vol->vol_type == UBI_STATIC_VOLUME) {
471                         err = -EROFS;
472                         break;
473                 }
474
475                 /* Validate the request */
476                 err = -EINVAL;
477                 if (req.lnum < 0 || req.lnum >= vol->reserved_pebs ||
478                     req.bytes < 0 || req.lnum >= vol->usable_leb_size)
479                         break;
480                 if (req.dtype != UBI_LONGTERM && req.dtype != UBI_SHORTTERM &&
481                     req.dtype != UBI_UNKNOWN)
482                         break;
483
484                 err = get_exclusive(desc);
485                 if (err < 0)
486                         break;
487
488                 err = ubi_start_leb_change(ubi, vol, &req);
489                 if (req.bytes == 0)
490                         revoke_exclusive(desc, UBI_READWRITE);
491                 break;
492         }
493
494 #ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
495         /* Logical eraseblock erasure command */
496         case UBI_IOCEBER:
497         {
498                 int32_t lnum;
499
500                 err = get_user(lnum, (__user int32_t *)argp);
501                 if (err) {
502                         err = -EFAULT;
503                         break;
504                 }
505
506                 if (desc->mode == UBI_READONLY ||
507                     vol->vol_type == UBI_STATIC_VOLUME) {
508                         err = -EROFS;
509                         break;
510                 }
511
512                 if (lnum < 0 || lnum >= vol->reserved_pebs) {
513                         err = -EINVAL;
514                         break;
515                 }
516
517                 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum);
518                 err = ubi_eba_unmap_leb(ubi, vol, lnum);
519                 if (err)
520                         break;
521
522                 err = ubi_wl_flush(ubi);
523                 break;
524         }
525 #endif
526
527         default:
528                 err = -ENOTTY;
529                 break;
530         }
531
532         return err;
533 }
534
535 /**
536  * verify_mkvol_req - verify volume creation request.
537  * @ubi: UBI device description object
538  * @req: the request to check
539  *
540  * This function zero if the request is correct, and %-EINVAL if not.
541  */
542 static int verify_mkvol_req(const struct ubi_device *ubi,
543                             const struct ubi_mkvol_req *req)
544 {
545         int n, err = -EINVAL;
546
547         if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 ||
548             req->name_len < 0)
549                 goto bad;
550
551         if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) &&
552             req->vol_id != UBI_VOL_NUM_AUTO)
553                 goto bad;
554
555         if (req->alignment == 0)
556                 goto bad;
557
558         if (req->bytes == 0)
559                 goto bad;
560
561         if (req->vol_type != UBI_DYNAMIC_VOLUME &&
562             req->vol_type != UBI_STATIC_VOLUME)
563                 goto bad;
564
565         if (req->alignment > ubi->leb_size)
566                 goto bad;
567
568         n = req->alignment & (ubi->min_io_size - 1);
569         if (req->alignment != 1 && n)
570                 goto bad;
571
572         if (req->name_len > UBI_VOL_NAME_MAX) {
573                 err = -ENAMETOOLONG;
574                 goto bad;
575         }
576
577         n = strnlen(req->name, req->name_len + 1);
578         if (n != req->name_len)
579                 goto bad;
580
581         return 0;
582
583 bad:
584         dbg_err("bad volume creation request");
585         ubi_dbg_dump_mkvol_req(req);
586         return err;
587 }
588
589 /**
590  * verify_rsvol_req - verify volume re-size request.
591  * @ubi: UBI device description object
592  * @req: the request to check
593  *
594  * This function returns zero if the request is correct, and %-EINVAL if not.
595  */
596 static int verify_rsvol_req(const struct ubi_device *ubi,
597                             const struct ubi_rsvol_req *req)
598 {
599         if (req->bytes <= 0)
600                 return -EINVAL;
601
602         if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots)
603                 return -EINVAL;
604
605         return 0;
606 }
607
608 /**
609  * rename_volumes - rename UBI volumes.
610  * @ubi: UBI device description object
611  * @req: volumes re-name request
612  *
613  * This is a helper function for the volume re-name IOCTL which validates the
614  * the request, opens the volume and calls corresponding volumes management
615  * function. Returns zero in case of success and a negative error code in case
616  * of failure.
617  */
618 static int rename_volumes(struct ubi_device *ubi,
619                           struct ubi_rnvol_req *req)
620 {
621         int i, n, err;
622         struct list_head rename_list;
623         struct ubi_rename_entry *re, *re1;
624
625         if (req->count < 0 || req->count > UBI_MAX_RNVOL)
626                 return -EINVAL;
627
628         if (req->count == 0)
629                 return 0;
630
631         /* Validate volume IDs and names in the request */
632         for (i = 0; i < req->count; i++) {
633                 if (req->ents[i].vol_id < 0 ||
634                     req->ents[i].vol_id >= ubi->vtbl_slots)
635                         return -EINVAL;
636                 if (req->ents[i].name_len < 0)
637                         return -EINVAL;
638                 if (req->ents[i].name_len > UBI_VOL_NAME_MAX)
639                         return -ENAMETOOLONG;
640                 req->ents[i].name[req->ents[i].name_len] = '\0';
641                 n = strlen(req->ents[i].name);
642                 if (n != req->ents[i].name_len)
643                         err = -EINVAL;
644         }
645
646         /* Make sure volume IDs and names are unique */
647         for (i = 0; i < req->count - 1; i++) {
648                 for (n = i + 1; n < req->count; n++) {
649                         if (req->ents[i].vol_id == req->ents[n].vol_id) {
650                                 dbg_err("duplicated volume id %d",
651                                         req->ents[i].vol_id);
652                                 return -EINVAL;
653                         }
654                         if (!strcmp(req->ents[i].name, req->ents[n].name)) {
655                                 dbg_err("duplicated volume name \"%s\"",
656                                         req->ents[i].name);
657                                 return -EINVAL;
658                         }
659                 }
660         }
661
662         /* Create the re-name list */
663         INIT_LIST_HEAD(&rename_list);
664         for (i = 0; i < req->count; i++) {
665                 int vol_id = req->ents[i].vol_id;
666                 int name_len = req->ents[i].name_len;
667                 const char *name = req->ents[i].name;
668
669                 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
670                 if (!re) {
671                         err = -ENOMEM;
672                         goto out_free;
673                 }
674
675                 re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
676                 if (IS_ERR(re->desc)) {
677                         err = PTR_ERR(re->desc);
678                         dbg_err("cannot open volume %d, error %d", vol_id, err);
679                         kfree(re);
680                         goto out_free;
681                 }
682
683                 /* Skip this re-naming if the name does not really change */
684                 if (re->desc->vol->name_len == name_len &&
685                     !memcmp(re->desc->vol->name, name, name_len)) {
686                         ubi_close_volume(re->desc);
687                         kfree(re);
688                         continue;
689                 }
690
691                 re->new_name_len = name_len;
692                 memcpy(re->new_name, name, name_len);
693                 list_add_tail(&re->list, &rename_list);
694                 dbg_msg("will rename volume %d from \"%s\" to \"%s\"",
695                         vol_id, re->desc->vol->name, name);
696         }
697
698         if (list_empty(&rename_list))
699                 return 0;
700
701         /* Find out the volumes which have to be removed */
702         list_for_each_entry(re, &rename_list, list) {
703                 struct ubi_volume_desc *desc;
704                 int no_remove_needed = 0;
705
706                 /*
707                  * Volume @re->vol_id is going to be re-named to
708                  * @re->new_name, while its current name is @name. If a volume
709                  * with name @re->new_name currently exists, it has to be
710                  * removed, unless it is also re-named in the request (@req).
711                  */
712                 list_for_each_entry(re1, &rename_list, list) {
713                         if (re->new_name_len == re1->desc->vol->name_len &&
714                             !memcmp(re->new_name, re1->desc->vol->name,
715                                     re1->desc->vol->name_len)) {
716                                 no_remove_needed = 1;
717                                 break;
718                         }
719                 }
720
721                 if (no_remove_needed)
722                         continue;
723
724                 /*
725                  * It seems we need to remove volume with name @re->new_name,
726                  * if it exists.
727                  */
728                 desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name, UBI_EXCLUSIVE);
729                 if (IS_ERR(desc)) {
730                         err = PTR_ERR(desc);
731                         if (err == -ENODEV)
732                                 /* Re-naming into a non-existing volume name */
733                                 continue;
734
735                         /* The volume exists but busy, or an error occurred */
736                         dbg_err("cannot open volume \"%s\", error %d",
737                                 re->new_name, err);
738                         goto out_free;
739                 }
740
741                 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
742                 if (!re) {
743                         err = -ENOMEM;
744                         ubi_close_volume(desc);
745                         goto out_free;
746                 }
747
748                 re->remove = 1;
749                 re->desc = desc;
750                 list_add(&re->list, &rename_list);
751                 dbg_msg("will remove volume %d, name \"%s\"",
752                         re->desc->vol->vol_id, re->desc->vol->name);
753         }
754
755         mutex_lock(&ubi->volumes_mutex);
756         err = ubi_rename_volumes(ubi, &rename_list);
757         mutex_unlock(&ubi->volumes_mutex);
758
759 out_free:
760         list_for_each_entry_safe(re, re1, &rename_list, list) {
761                 ubi_close_volume(re->desc);
762                 list_del(&re->list);
763                 kfree(re);
764         }
765         return err;
766 }
767
768 static int ubi_cdev_ioctl(struct inode *inode, struct file *file,
769                           unsigned int cmd, unsigned long arg)
770 {
771         int err = 0;
772         struct ubi_device *ubi;
773         struct ubi_volume_desc *desc;
774         void __user *argp = (void __user *)arg;
775
776         if (!capable(CAP_SYS_RESOURCE))
777                 return -EPERM;
778
779         ubi = ubi_get_by_major(imajor(inode));
780         if (!ubi)
781                 return -ENODEV;
782
783         switch (cmd) {
784         /* Create volume command */
785         case UBI_IOCMKVOL:
786         {
787                 struct ubi_mkvol_req req;
788
789                 dbg_gen("create volume");
790                 err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req));
791                 if (err) {
792                         err = -EFAULT;
793                         break;
794                 }
795
796                 req.name[req.name_len] = '\0';
797                 err = verify_mkvol_req(ubi, &req);
798                 if (err)
799                         break;
800
801                 mutex_lock(&ubi->volumes_mutex);
802                 err = ubi_create_volume(ubi, &req);
803                 mutex_unlock(&ubi->volumes_mutex);
804                 if (err)
805                         break;
806
807                 err = put_user(req.vol_id, (__user int32_t *)argp);
808                 if (err)
809                         err = -EFAULT;
810
811                 break;
812         }
813
814         /* Remove volume command */
815         case UBI_IOCRMVOL:
816         {
817                 int vol_id;
818
819                 dbg_gen("remove volume");
820                 err = get_user(vol_id, (__user int32_t *)argp);
821                 if (err) {
822                         err = -EFAULT;
823                         break;
824                 }
825
826                 desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
827                 if (IS_ERR(desc)) {
828                         err = PTR_ERR(desc);
829                         break;
830                 }
831
832                 mutex_lock(&ubi->volumes_mutex);
833                 err = ubi_remove_volume(desc, 0);
834                 mutex_unlock(&ubi->volumes_mutex);
835
836                 /*
837                  * The volume is deleted (unless an error occurred), and the
838                  * 'struct ubi_volume' object will be freed when
839                  * 'ubi_close_volume()' will call 'put_device()'.
840                  */
841                 ubi_close_volume(desc);
842                 break;
843         }
844
845         /* Re-size volume command */
846         case UBI_IOCRSVOL:
847         {
848                 int pebs;
849                 uint64_t tmp;
850                 struct ubi_rsvol_req req;
851
852                 dbg_gen("re-size volume");
853                 err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req));
854                 if (err) {
855                         err = -EFAULT;
856                         break;
857                 }
858
859                 err = verify_rsvol_req(ubi, &req);
860                 if (err)
861                         break;
862
863                 desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE);
864                 if (IS_ERR(desc)) {
865                         err = PTR_ERR(desc);
866                         break;
867                 }
868
869                 tmp = req.bytes;
870                 pebs = !!do_div(tmp, desc->vol->usable_leb_size);
871                 pebs += tmp;
872
873                 mutex_lock(&ubi->volumes_mutex);
874                 err = ubi_resize_volume(desc, pebs);
875                 mutex_unlock(&ubi->volumes_mutex);
876                 ubi_close_volume(desc);
877                 break;
878         }
879
880         /* Re-name volumes command */
881         case UBI_IOCRNVOL:
882         {
883                 struct ubi_rnvol_req *req;
884
885                 dbg_msg("re-name volumes");
886                 req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL);
887                 if (!req) {
888                         err = -ENOMEM;
889                         break;
890                 };
891
892                 err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req));
893                 if (err) {
894                         err = -EFAULT;
895                         kfree(req);
896                         break;
897                 }
898
899                 mutex_lock(&ubi->mult_mutex);
900                 err = rename_volumes(ubi, req);
901                 mutex_unlock(&ubi->mult_mutex);
902                 kfree(req);
903                 break;
904         }
905
906         default:
907                 err = -ENOTTY;
908                 break;
909         }
910
911         ubi_put_device(ubi);
912         return err;
913 }
914
915 static int ctrl_cdev_ioctl(struct inode *inode, struct file *file,
916                            unsigned int cmd, unsigned long arg)
917 {
918         int err = 0;
919         void __user *argp = (void __user *)arg;
920
921         if (!capable(CAP_SYS_RESOURCE))
922                 return -EPERM;
923
924         switch (cmd) {
925         /* Attach an MTD device command */
926         case UBI_IOCATT:
927         {
928                 struct ubi_attach_req req;
929                 struct mtd_info *mtd;
930
931                 dbg_gen("attach MTD device");
932                 err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req));
933                 if (err) {
934                         err = -EFAULT;
935                         break;
936                 }
937
938                 if (req.mtd_num < 0 ||
939                     (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) {
940                         err = -EINVAL;
941                         break;
942                 }
943
944                 mtd = get_mtd_device(NULL, req.mtd_num);
945                 if (IS_ERR(mtd)) {
946                         err = PTR_ERR(mtd);
947                         break;
948                 }
949
950                 /*
951                  * Note, further request verification is done by
952                  * 'ubi_attach_mtd_dev()'.
953                  */
954                 mutex_lock(&ubi_devices_mutex);
955                 err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset);
956                 mutex_unlock(&ubi_devices_mutex);
957                 if (err < 0)
958                         put_mtd_device(mtd);
959                 else
960                         /* @err contains UBI device number */
961                         err = put_user(err, (__user int32_t *)argp);
962
963                 break;
964         }
965
966         /* Detach an MTD device command */
967         case UBI_IOCDET:
968         {
969                 int ubi_num;
970
971                 dbg_gen("dettach MTD device");
972                 err = get_user(ubi_num, (__user int32_t *)argp);
973                 if (err) {
974                         err = -EFAULT;
975                         break;
976                 }
977
978                 mutex_lock(&ubi_devices_mutex);
979                 err = ubi_detach_mtd_dev(ubi_num, 0);
980                 mutex_unlock(&ubi_devices_mutex);
981                 break;
982         }
983
984         default:
985                 err = -ENOTTY;
986                 break;
987         }
988
989         return err;
990 }
991
992 /* UBI control character device operations */
993 struct file_operations ubi_ctrl_cdev_operations = {
994         .ioctl = ctrl_cdev_ioctl,
995         .owner = THIS_MODULE,
996 };
997
998 /* UBI character device operations */
999 struct file_operations ubi_cdev_operations = {
1000         .owner = THIS_MODULE,
1001         .ioctl = ubi_cdev_ioctl,
1002         .llseek = no_llseek,
1003 };
1004
1005 /* UBI volume character device operations */
1006 struct file_operations ubi_vol_cdev_operations = {
1007         .owner   = THIS_MODULE,
1008         .open    = vol_cdev_open,
1009         .release = vol_cdev_release,
1010         .llseek  = vol_cdev_llseek,
1011         .read    = vol_cdev_read,
1012         .write   = vol_cdev_write,
1013         .ioctl   = vol_cdev_ioctl,
1014 };