Loading...
1/*
2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2007
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Author: Artem Bityutskiy (Битюцкий Артём),
20 * Frank Haverkamp
21 */
22
23/*
24 * This file includes UBI initialization and building of UBI devices.
25 *
26 * When UBI is initialized, it attaches all the MTD devices specified as the
27 * module load parameters or the kernel boot parameters. If MTD devices were
28 * specified, UBI does not attach any MTD device, but it is possible to do
29 * later using the "UBI control device".
30 *
31 * At the moment we only attach UBI devices by scanning, which will become a
32 * bottleneck when flashes reach certain large size. Then one may improve UBI
33 * and add other methods, although it does not seem to be easy to do.
34 */
35
36#include <linux/err.h>
37#include <linux/module.h>
38#include <linux/moduleparam.h>
39#include <linux/stringify.h>
40#include <linux/namei.h>
41#include <linux/stat.h>
42#include <linux/miscdevice.h>
43#include <linux/log2.h>
44#include <linux/kthread.h>
45#include <linux/kernel.h>
46#include <linux/slab.h>
47#include "ubi.h"
48
49/* Maximum length of the 'mtd=' parameter */
50#define MTD_PARAM_LEN_MAX 64
51
52#ifdef CONFIG_MTD_UBI_MODULE
53#define ubi_is_module() 1
54#else
55#define ubi_is_module() 0
56#endif
57
58/**
59 * struct mtd_dev_param - MTD device parameter description data structure.
60 * @name: MTD character device node path, MTD device name, or MTD device number
61 * string
62 * @vid_hdr_offs: VID header offset
63 */
64struct mtd_dev_param {
65 char name[MTD_PARAM_LEN_MAX];
66 int vid_hdr_offs;
67};
68
69/* Numbers of elements set in the @mtd_dev_param array */
70static int __initdata mtd_devs;
71
72/* MTD devices specification parameters */
73static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES];
74
75/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
76struct class *ubi_class;
77
78/* Slab cache for wear-leveling entries */
79struct kmem_cache *ubi_wl_entry_slab;
80
81/* UBI control character device */
82static struct miscdevice ubi_ctrl_cdev = {
83 .minor = MISC_DYNAMIC_MINOR,
84 .name = "ubi_ctrl",
85 .fops = &ubi_ctrl_cdev_operations,
86};
87
88/* All UBI devices in system */
89static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
90
91/* Serializes UBI devices creations and removals */
92DEFINE_MUTEX(ubi_devices_mutex);
93
94/* Protects @ubi_devices and @ubi->ref_count */
95static DEFINE_SPINLOCK(ubi_devices_lock);
96
97/* "Show" method for files in '/<sysfs>/class/ubi/' */
98static ssize_t ubi_version_show(struct class *class,
99 struct class_attribute *attr, char *buf)
100{
101 return sprintf(buf, "%d\n", UBI_VERSION);
102}
103
104/* UBI version attribute ('/<sysfs>/class/ubi/version') */
105static struct class_attribute ubi_version =
106 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
107
108static ssize_t dev_attribute_show(struct device *dev,
109 struct device_attribute *attr, char *buf);
110
111/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
112static struct device_attribute dev_eraseblock_size =
113 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
114static struct device_attribute dev_avail_eraseblocks =
115 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
116static struct device_attribute dev_total_eraseblocks =
117 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
118static struct device_attribute dev_volumes_count =
119 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
120static struct device_attribute dev_max_ec =
121 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
122static struct device_attribute dev_reserved_for_bad =
123 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
124static struct device_attribute dev_bad_peb_count =
125 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
126static struct device_attribute dev_max_vol_count =
127 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
128static struct device_attribute dev_min_io_size =
129 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
130static struct device_attribute dev_bgt_enabled =
131 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
132static struct device_attribute dev_mtd_num =
133 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
134
135/**
136 * ubi_volume_notify - send a volume change notification.
137 * @ubi: UBI device description object
138 * @vol: volume description object of the changed volume
139 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
140 *
141 * This is a helper function which notifies all subscribers about a volume
142 * change event (creation, removal, re-sizing, re-naming, updating). Returns
143 * zero in case of success and a negative error code in case of failure.
144 */
145int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
146{
147 struct ubi_notification nt;
148
149 ubi_do_get_device_info(ubi, &nt.di);
150 ubi_do_get_volume_info(ubi, vol, &nt.vi);
151 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
152}
153
154/**
155 * ubi_notify_all - send a notification to all volumes.
156 * @ubi: UBI device description object
157 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
158 * @nb: the notifier to call
159 *
160 * This function walks all volumes of UBI device @ubi and sends the @ntype
161 * notification for each volume. If @nb is %NULL, then all registered notifiers
162 * are called, otherwise only the @nb notifier is called. Returns the number of
163 * sent notifications.
164 */
165int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
166{
167 struct ubi_notification nt;
168 int i, count = 0;
169
170 ubi_do_get_device_info(ubi, &nt.di);
171
172 mutex_lock(&ubi->device_mutex);
173 for (i = 0; i < ubi->vtbl_slots; i++) {
174 /*
175 * Since the @ubi->device is locked, and we are not going to
176 * change @ubi->volumes, we do not have to lock
177 * @ubi->volumes_lock.
178 */
179 if (!ubi->volumes[i])
180 continue;
181
182 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
183 if (nb)
184 nb->notifier_call(nb, ntype, &nt);
185 else
186 blocking_notifier_call_chain(&ubi_notifiers, ntype,
187 &nt);
188 count += 1;
189 }
190 mutex_unlock(&ubi->device_mutex);
191
192 return count;
193}
194
195/**
196 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
197 * @nb: the notifier to call
198 *
199 * This function walks all UBI devices and volumes and sends the
200 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
201 * registered notifiers are called, otherwise only the @nb notifier is called.
202 * Returns the number of sent notifications.
203 */
204int ubi_enumerate_volumes(struct notifier_block *nb)
205{
206 int i, count = 0;
207
208 /*
209 * Since the @ubi_devices_mutex is locked, and we are not going to
210 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
211 */
212 for (i = 0; i < UBI_MAX_DEVICES; i++) {
213 struct ubi_device *ubi = ubi_devices[i];
214
215 if (!ubi)
216 continue;
217 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
218 }
219
220 return count;
221}
222
223/**
224 * ubi_get_device - get UBI device.
225 * @ubi_num: UBI device number
226 *
227 * This function returns UBI device description object for UBI device number
228 * @ubi_num, or %NULL if the device does not exist. This function increases the
229 * device reference count to prevent removal of the device. In other words, the
230 * device cannot be removed if its reference count is not zero.
231 */
232struct ubi_device *ubi_get_device(int ubi_num)
233{
234 struct ubi_device *ubi;
235
236 spin_lock(&ubi_devices_lock);
237 ubi = ubi_devices[ubi_num];
238 if (ubi) {
239 ubi_assert(ubi->ref_count >= 0);
240 ubi->ref_count += 1;
241 get_device(&ubi->dev);
242 }
243 spin_unlock(&ubi_devices_lock);
244
245 return ubi;
246}
247
248/**
249 * ubi_put_device - drop an UBI device reference.
250 * @ubi: UBI device description object
251 */
252void ubi_put_device(struct ubi_device *ubi)
253{
254 spin_lock(&ubi_devices_lock);
255 ubi->ref_count -= 1;
256 put_device(&ubi->dev);
257 spin_unlock(&ubi_devices_lock);
258}
259
260/**
261 * ubi_get_by_major - get UBI device by character device major number.
262 * @major: major number
263 *
264 * This function is similar to 'ubi_get_device()', but it searches the device
265 * by its major number.
266 */
267struct ubi_device *ubi_get_by_major(int major)
268{
269 int i;
270 struct ubi_device *ubi;
271
272 spin_lock(&ubi_devices_lock);
273 for (i = 0; i < UBI_MAX_DEVICES; i++) {
274 ubi = ubi_devices[i];
275 if (ubi && MAJOR(ubi->cdev.dev) == major) {
276 ubi_assert(ubi->ref_count >= 0);
277 ubi->ref_count += 1;
278 get_device(&ubi->dev);
279 spin_unlock(&ubi_devices_lock);
280 return ubi;
281 }
282 }
283 spin_unlock(&ubi_devices_lock);
284
285 return NULL;
286}
287
288/**
289 * ubi_major2num - get UBI device number by character device major number.
290 * @major: major number
291 *
292 * This function searches UBI device number object by its major number. If UBI
293 * device was not found, this function returns -ENODEV, otherwise the UBI device
294 * number is returned.
295 */
296int ubi_major2num(int major)
297{
298 int i, ubi_num = -ENODEV;
299
300 spin_lock(&ubi_devices_lock);
301 for (i = 0; i < UBI_MAX_DEVICES; i++) {
302 struct ubi_device *ubi = ubi_devices[i];
303
304 if (ubi && MAJOR(ubi->cdev.dev) == major) {
305 ubi_num = ubi->ubi_num;
306 break;
307 }
308 }
309 spin_unlock(&ubi_devices_lock);
310
311 return ubi_num;
312}
313
314/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
315static ssize_t dev_attribute_show(struct device *dev,
316 struct device_attribute *attr, char *buf)
317{
318 ssize_t ret;
319 struct ubi_device *ubi;
320
321 /*
322 * The below code looks weird, but it actually makes sense. We get the
323 * UBI device reference from the contained 'struct ubi_device'. But it
324 * is unclear if the device was removed or not yet. Indeed, if the
325 * device was removed before we increased its reference count,
326 * 'ubi_get_device()' will return -ENODEV and we fail.
327 *
328 * Remember, 'struct ubi_device' is freed in the release function, so
329 * we still can use 'ubi->ubi_num'.
330 */
331 ubi = container_of(dev, struct ubi_device, dev);
332 ubi = ubi_get_device(ubi->ubi_num);
333 if (!ubi)
334 return -ENODEV;
335
336 if (attr == &dev_eraseblock_size)
337 ret = sprintf(buf, "%d\n", ubi->leb_size);
338 else if (attr == &dev_avail_eraseblocks)
339 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
340 else if (attr == &dev_total_eraseblocks)
341 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
342 else if (attr == &dev_volumes_count)
343 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
344 else if (attr == &dev_max_ec)
345 ret = sprintf(buf, "%d\n", ubi->max_ec);
346 else if (attr == &dev_reserved_for_bad)
347 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
348 else if (attr == &dev_bad_peb_count)
349 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
350 else if (attr == &dev_max_vol_count)
351 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
352 else if (attr == &dev_min_io_size)
353 ret = sprintf(buf, "%d\n", ubi->min_io_size);
354 else if (attr == &dev_bgt_enabled)
355 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
356 else if (attr == &dev_mtd_num)
357 ret = sprintf(buf, "%d\n", ubi->mtd->index);
358 else
359 ret = -EINVAL;
360
361 ubi_put_device(ubi);
362 return ret;
363}
364
365static void dev_release(struct device *dev)
366{
367 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
368
369 kfree(ubi);
370}
371
372/**
373 * ubi_sysfs_init - initialize sysfs for an UBI device.
374 * @ubi: UBI device description object
375 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
376 * taken
377 *
378 * This function returns zero in case of success and a negative error code in
379 * case of failure.
380 */
381static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
382{
383 int err;
384
385 ubi->dev.release = dev_release;
386 ubi->dev.devt = ubi->cdev.dev;
387 ubi->dev.class = ubi_class;
388 dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
389 err = device_register(&ubi->dev);
390 if (err)
391 return err;
392
393 *ref = 1;
394 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
395 if (err)
396 return err;
397 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
398 if (err)
399 return err;
400 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
401 if (err)
402 return err;
403 err = device_create_file(&ubi->dev, &dev_volumes_count);
404 if (err)
405 return err;
406 err = device_create_file(&ubi->dev, &dev_max_ec);
407 if (err)
408 return err;
409 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
410 if (err)
411 return err;
412 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
413 if (err)
414 return err;
415 err = device_create_file(&ubi->dev, &dev_max_vol_count);
416 if (err)
417 return err;
418 err = device_create_file(&ubi->dev, &dev_min_io_size);
419 if (err)
420 return err;
421 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
422 if (err)
423 return err;
424 err = device_create_file(&ubi->dev, &dev_mtd_num);
425 return err;
426}
427
428/**
429 * ubi_sysfs_close - close sysfs for an UBI device.
430 * @ubi: UBI device description object
431 */
432static void ubi_sysfs_close(struct ubi_device *ubi)
433{
434 device_remove_file(&ubi->dev, &dev_mtd_num);
435 device_remove_file(&ubi->dev, &dev_bgt_enabled);
436 device_remove_file(&ubi->dev, &dev_min_io_size);
437 device_remove_file(&ubi->dev, &dev_max_vol_count);
438 device_remove_file(&ubi->dev, &dev_bad_peb_count);
439 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
440 device_remove_file(&ubi->dev, &dev_max_ec);
441 device_remove_file(&ubi->dev, &dev_volumes_count);
442 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
443 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
444 device_remove_file(&ubi->dev, &dev_eraseblock_size);
445 device_unregister(&ubi->dev);
446}
447
448/**
449 * kill_volumes - destroy all user volumes.
450 * @ubi: UBI device description object
451 */
452static void kill_volumes(struct ubi_device *ubi)
453{
454 int i;
455
456 for (i = 0; i < ubi->vtbl_slots; i++)
457 if (ubi->volumes[i])
458 ubi_free_volume(ubi, ubi->volumes[i]);
459}
460
461/**
462 * uif_init - initialize user interfaces for an UBI device.
463 * @ubi: UBI device description object
464 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
465 * taken, otherwise set to %0
466 *
467 * This function initializes various user interfaces for an UBI device. If the
468 * initialization fails at an early stage, this function frees all the
469 * resources it allocated, returns an error, and @ref is set to %0. However,
470 * if the initialization fails after the UBI device was registered in the
471 * driver core subsystem, this function takes a reference to @ubi->dev, because
472 * otherwise the release function ('dev_release()') would free whole @ubi
473 * object. The @ref argument is set to %1 in this case. The caller has to put
474 * this reference.
475 *
476 * This function returns zero in case of success and a negative error code in
477 * case of failure.
478 */
479static int uif_init(struct ubi_device *ubi, int *ref)
480{
481 int i, err;
482 dev_t dev;
483
484 *ref = 0;
485 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
486
487 /*
488 * Major numbers for the UBI character devices are allocated
489 * dynamically. Major numbers of volume character devices are
490 * equivalent to ones of the corresponding UBI character device. Minor
491 * numbers of UBI character devices are 0, while minor numbers of
492 * volume character devices start from 1. Thus, we allocate one major
493 * number and ubi->vtbl_slots + 1 minor numbers.
494 */
495 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
496 if (err) {
497 ubi_err("cannot register UBI character devices");
498 return err;
499 }
500
501 ubi_assert(MINOR(dev) == 0);
502 cdev_init(&ubi->cdev, &ubi_cdev_operations);
503 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
504 ubi->cdev.owner = THIS_MODULE;
505
506 err = cdev_add(&ubi->cdev, dev, 1);
507 if (err) {
508 ubi_err("cannot add character device");
509 goto out_unreg;
510 }
511
512 err = ubi_sysfs_init(ubi, ref);
513 if (err)
514 goto out_sysfs;
515
516 for (i = 0; i < ubi->vtbl_slots; i++)
517 if (ubi->volumes[i]) {
518 err = ubi_add_volume(ubi, ubi->volumes[i]);
519 if (err) {
520 ubi_err("cannot add volume %d", i);
521 goto out_volumes;
522 }
523 }
524
525 return 0;
526
527out_volumes:
528 kill_volumes(ubi);
529out_sysfs:
530 if (*ref)
531 get_device(&ubi->dev);
532 ubi_sysfs_close(ubi);
533 cdev_del(&ubi->cdev);
534out_unreg:
535 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
536 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
537 return err;
538}
539
540/**
541 * uif_close - close user interfaces for an UBI device.
542 * @ubi: UBI device description object
543 *
544 * Note, since this function un-registers UBI volume device objects (@vol->dev),
545 * the memory allocated voe the volumes is freed as well (in the release
546 * function).
547 */
548static void uif_close(struct ubi_device *ubi)
549{
550 kill_volumes(ubi);
551 ubi_sysfs_close(ubi);
552 cdev_del(&ubi->cdev);
553 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
554}
555
556/**
557 * free_internal_volumes - free internal volumes.
558 * @ubi: UBI device description object
559 */
560static void free_internal_volumes(struct ubi_device *ubi)
561{
562 int i;
563
564 for (i = ubi->vtbl_slots;
565 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
566 kfree(ubi->volumes[i]->eba_tbl);
567 kfree(ubi->volumes[i]);
568 }
569}
570
571/**
572 * attach_by_scanning - attach an MTD device using scanning method.
573 * @ubi: UBI device descriptor
574 *
575 * This function returns zero in case of success and a negative error code in
576 * case of failure.
577 *
578 * Note, currently this is the only method to attach UBI devices. Hopefully in
579 * the future we'll have more scalable attaching methods and avoid full media
580 * scanning. But even in this case scanning will be needed as a fall-back
581 * attaching method if there are some on-flash table corruptions.
582 */
583static int attach_by_scanning(struct ubi_device *ubi)
584{
585 int err;
586 struct ubi_scan_info *si;
587
588 si = ubi_scan(ubi);
589 if (IS_ERR(si))
590 return PTR_ERR(si);
591
592 ubi->bad_peb_count = si->bad_peb_count;
593 ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
594 ubi->corr_peb_count = si->corr_peb_count;
595 ubi->max_ec = si->max_ec;
596 ubi->mean_ec = si->mean_ec;
597 ubi_msg("max. sequence number: %llu", si->max_sqnum);
598
599 err = ubi_read_volume_table(ubi, si);
600 if (err)
601 goto out_si;
602
603 err = ubi_wl_init_scan(ubi, si);
604 if (err)
605 goto out_vtbl;
606
607 err = ubi_eba_init_scan(ubi, si);
608 if (err)
609 goto out_wl;
610
611 ubi_scan_destroy_si(si);
612 return 0;
613
614out_wl:
615 ubi_wl_close(ubi);
616out_vtbl:
617 free_internal_volumes(ubi);
618 vfree(ubi->vtbl);
619out_si:
620 ubi_scan_destroy_si(si);
621 return err;
622}
623
624/**
625 * io_init - initialize I/O sub-system for a given UBI device.
626 * @ubi: UBI device description object
627 *
628 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
629 * assumed:
630 * o EC header is always at offset zero - this cannot be changed;
631 * o VID header starts just after the EC header at the closest address
632 * aligned to @io->hdrs_min_io_size;
633 * o data starts just after the VID header at the closest address aligned to
634 * @io->min_io_size
635 *
636 * This function returns zero in case of success and a negative error code in
637 * case of failure.
638 */
639static int io_init(struct ubi_device *ubi)
640{
641 if (ubi->mtd->numeraseregions != 0) {
642 /*
643 * Some flashes have several erase regions. Different regions
644 * may have different eraseblock size and other
645 * characteristics. It looks like mostly multi-region flashes
646 * have one "main" region and one or more small regions to
647 * store boot loader code or boot parameters or whatever. I
648 * guess we should just pick the largest region. But this is
649 * not implemented.
650 */
651 ubi_err("multiple regions, not implemented");
652 return -EINVAL;
653 }
654
655 if (ubi->vid_hdr_offset < 0)
656 return -EINVAL;
657
658 /*
659 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
660 * physical eraseblocks maximum.
661 */
662
663 ubi->peb_size = ubi->mtd->erasesize;
664 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
665 ubi->flash_size = ubi->mtd->size;
666
667 if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
668 ubi->bad_allowed = 1;
669
670 if (ubi->mtd->type == MTD_NORFLASH) {
671 ubi_assert(ubi->mtd->writesize == 1);
672 ubi->nor_flash = 1;
673 }
674
675 ubi->min_io_size = ubi->mtd->writesize;
676 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
677
678 /*
679 * Make sure minimal I/O unit is power of 2. Note, there is no
680 * fundamental reason for this assumption. It is just an optimization
681 * which allows us to avoid costly division operations.
682 */
683 if (!is_power_of_2(ubi->min_io_size)) {
684 ubi_err("min. I/O unit (%d) is not power of 2",
685 ubi->min_io_size);
686 return -EINVAL;
687 }
688
689 ubi_assert(ubi->hdrs_min_io_size > 0);
690 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
691 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
692
693 ubi->max_write_size = ubi->mtd->writebufsize;
694 /*
695 * Maximum write size has to be greater or equivalent to min. I/O
696 * size, and be multiple of min. I/O size.
697 */
698 if (ubi->max_write_size < ubi->min_io_size ||
699 ubi->max_write_size % ubi->min_io_size ||
700 !is_power_of_2(ubi->max_write_size)) {
701 ubi_err("bad write buffer size %d for %d min. I/O unit",
702 ubi->max_write_size, ubi->min_io_size);
703 return -EINVAL;
704 }
705
706 /* Calculate default aligned sizes of EC and VID headers */
707 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
708 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
709
710 dbg_msg("min_io_size %d", ubi->min_io_size);
711 dbg_msg("max_write_size %d", ubi->max_write_size);
712 dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
713 dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
714 dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
715
716 if (ubi->vid_hdr_offset == 0)
717 /* Default offset */
718 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
719 ubi->ec_hdr_alsize;
720 else {
721 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
722 ~(ubi->hdrs_min_io_size - 1);
723 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
724 ubi->vid_hdr_aloffset;
725 }
726
727 /* Similar for the data offset */
728 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
729 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
730
731 dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
732 dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
733 dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
734 dbg_msg("leb_start %d", ubi->leb_start);
735
736 /* The shift must be aligned to 32-bit boundary */
737 if (ubi->vid_hdr_shift % 4) {
738 ubi_err("unaligned VID header shift %d",
739 ubi->vid_hdr_shift);
740 return -EINVAL;
741 }
742
743 /* Check sanity */
744 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
745 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
746 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
747 ubi->leb_start & (ubi->min_io_size - 1)) {
748 ubi_err("bad VID header (%d) or data offsets (%d)",
749 ubi->vid_hdr_offset, ubi->leb_start);
750 return -EINVAL;
751 }
752
753 /*
754 * Set maximum amount of physical erroneous eraseblocks to be 10%.
755 * Erroneous PEB are those which have read errors.
756 */
757 ubi->max_erroneous = ubi->peb_count / 10;
758 if (ubi->max_erroneous < 16)
759 ubi->max_erroneous = 16;
760 dbg_msg("max_erroneous %d", ubi->max_erroneous);
761
762 /*
763 * It may happen that EC and VID headers are situated in one minimal
764 * I/O unit. In this case we can only accept this UBI image in
765 * read-only mode.
766 */
767 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
768 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
769 "switch to read-only mode");
770 ubi->ro_mode = 1;
771 }
772
773 ubi->leb_size = ubi->peb_size - ubi->leb_start;
774
775 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
776 ubi_msg("MTD device %d is write-protected, attach in "
777 "read-only mode", ubi->mtd->index);
778 ubi->ro_mode = 1;
779 }
780
781 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
782 ubi->peb_size, ubi->peb_size >> 10);
783 ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
784 ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
785 if (ubi->hdrs_min_io_size != ubi->min_io_size)
786 ubi_msg("sub-page size: %d",
787 ubi->hdrs_min_io_size);
788 ubi_msg("VID header offset: %d (aligned %d)",
789 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
790 ubi_msg("data offset: %d", ubi->leb_start);
791
792 /*
793 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
794 * unfortunately, MTD does not provide this information. We should loop
795 * over all physical eraseblocks and invoke mtd->block_is_bad() for
796 * each physical eraseblock. So, we skip ubi->bad_peb_count
797 * uninitialized and initialize it after scanning.
798 */
799
800 return 0;
801}
802
803/**
804 * autoresize - re-size the volume which has the "auto-resize" flag set.
805 * @ubi: UBI device description object
806 * @vol_id: ID of the volume to re-size
807 *
808 * This function re-sizes the volume marked by the @UBI_VTBL_AUTORESIZE_FLG in
809 * the volume table to the largest possible size. See comments in ubi-header.h
810 * for more description of the flag. Returns zero in case of success and a
811 * negative error code in case of failure.
812 */
813static int autoresize(struct ubi_device *ubi, int vol_id)
814{
815 struct ubi_volume_desc desc;
816 struct ubi_volume *vol = ubi->volumes[vol_id];
817 int err, old_reserved_pebs = vol->reserved_pebs;
818
819 /*
820 * Clear the auto-resize flag in the volume in-memory copy of the
821 * volume table, and 'ubi_resize_volume()' will propagate this change
822 * to the flash.
823 */
824 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
825
826 if (ubi->avail_pebs == 0) {
827 struct ubi_vtbl_record vtbl_rec;
828
829 /*
830 * No available PEBs to re-size the volume, clear the flag on
831 * flash and exit.
832 */
833 memcpy(&vtbl_rec, &ubi->vtbl[vol_id],
834 sizeof(struct ubi_vtbl_record));
835 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
836 if (err)
837 ubi_err("cannot clean auto-resize flag for volume %d",
838 vol_id);
839 } else {
840 desc.vol = vol;
841 err = ubi_resize_volume(&desc,
842 old_reserved_pebs + ubi->avail_pebs);
843 if (err)
844 ubi_err("cannot auto-resize volume %d", vol_id);
845 }
846
847 if (err)
848 return err;
849
850 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
851 vol->name, old_reserved_pebs, vol->reserved_pebs);
852 return 0;
853}
854
855/**
856 * ubi_attach_mtd_dev - attach an MTD device.
857 * @mtd: MTD device description object
858 * @ubi_num: number to assign to the new UBI device
859 * @vid_hdr_offset: VID header offset
860 *
861 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
862 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
863 * which case this function finds a vacant device number and assigns it
864 * automatically. Returns the new UBI device number in case of success and a
865 * negative error code in case of failure.
866 *
867 * Note, the invocations of this function has to be serialized by the
868 * @ubi_devices_mutex.
869 */
870int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
871{
872 struct ubi_device *ubi;
873 int i, err, ref = 0;
874
875 /*
876 * Check if we already have the same MTD device attached.
877 *
878 * Note, this function assumes that UBI devices creations and deletions
879 * are serialized, so it does not take the &ubi_devices_lock.
880 */
881 for (i = 0; i < UBI_MAX_DEVICES; i++) {
882 ubi = ubi_devices[i];
883 if (ubi && mtd->index == ubi->mtd->index) {
884 dbg_err("mtd%d is already attached to ubi%d",
885 mtd->index, i);
886 return -EEXIST;
887 }
888 }
889
890 /*
891 * Make sure this MTD device is not emulated on top of an UBI volume
892 * already. Well, generally this recursion works fine, but there are
893 * different problems like the UBI module takes a reference to itself
894 * by attaching (and thus, opening) the emulated MTD device. This
895 * results in inability to unload the module. And in general it makes
896 * no sense to attach emulated MTD devices, so we prohibit this.
897 */
898 if (mtd->type == MTD_UBIVOLUME) {
899 ubi_err("refuse attaching mtd%d - it is already emulated on "
900 "top of UBI", mtd->index);
901 return -EINVAL;
902 }
903
904 if (ubi_num == UBI_DEV_NUM_AUTO) {
905 /* Search for an empty slot in the @ubi_devices array */
906 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
907 if (!ubi_devices[ubi_num])
908 break;
909 if (ubi_num == UBI_MAX_DEVICES) {
910 dbg_err("only %d UBI devices may be created",
911 UBI_MAX_DEVICES);
912 return -ENFILE;
913 }
914 } else {
915 if (ubi_num >= UBI_MAX_DEVICES)
916 return -EINVAL;
917
918 /* Make sure ubi_num is not busy */
919 if (ubi_devices[ubi_num]) {
920 dbg_err("ubi%d already exists", ubi_num);
921 return -EEXIST;
922 }
923 }
924
925 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
926 if (!ubi)
927 return -ENOMEM;
928
929 ubi->mtd = mtd;
930 ubi->ubi_num = ubi_num;
931 ubi->vid_hdr_offset = vid_hdr_offset;
932 ubi->autoresize_vol_id = -1;
933
934 mutex_init(&ubi->buf_mutex);
935 mutex_init(&ubi->ckvol_mutex);
936 mutex_init(&ubi->device_mutex);
937 spin_lock_init(&ubi->volumes_lock);
938
939 ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
940 dbg_msg("sizeof(struct ubi_scan_leb) %zu", sizeof(struct ubi_scan_leb));
941 dbg_msg("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
942
943 err = io_init(ubi);
944 if (err)
945 goto out_free;
946
947 err = -ENOMEM;
948 ubi->peb_buf1 = vmalloc(ubi->peb_size);
949 if (!ubi->peb_buf1)
950 goto out_free;
951
952 ubi->peb_buf2 = vmalloc(ubi->peb_size);
953 if (!ubi->peb_buf2)
954 goto out_free;
955
956 err = ubi_debugging_init_dev(ubi);
957 if (err)
958 goto out_free;
959
960 err = attach_by_scanning(ubi);
961 if (err) {
962 dbg_err("failed to attach by scanning, error %d", err);
963 goto out_debugging;
964 }
965
966 if (ubi->autoresize_vol_id != -1) {
967 err = autoresize(ubi, ubi->autoresize_vol_id);
968 if (err)
969 goto out_detach;
970 }
971
972 err = uif_init(ubi, &ref);
973 if (err)
974 goto out_detach;
975
976 err = ubi_debugfs_init_dev(ubi);
977 if (err)
978 goto out_uif;
979
980 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
981 if (IS_ERR(ubi->bgt_thread)) {
982 err = PTR_ERR(ubi->bgt_thread);
983 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
984 err);
985 goto out_debugfs;
986 }
987
988 ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num);
989 ubi_msg("MTD device name: \"%s\"", mtd->name);
990 ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
991 ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
992 ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
993 ubi_msg("number of corrupted PEBs: %d", ubi->corr_peb_count);
994 ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
995 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
996 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
997 ubi_msg("number of user volumes: %d",
998 ubi->vol_count - UBI_INT_VOL_COUNT);
999 ubi_msg("available PEBs: %d", ubi->avail_pebs);
1000 ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
1001 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
1002 ubi->beb_rsvd_pebs);
1003 ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
1004 ubi_msg("image sequence number: %d", ubi->image_seq);
1005
1006 /*
1007 * The below lock makes sure we do not race with 'ubi_thread()' which
1008 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1009 */
1010 spin_lock(&ubi->wl_lock);
1011 ubi->thread_enabled = 1;
1012 wake_up_process(ubi->bgt_thread);
1013 spin_unlock(&ubi->wl_lock);
1014
1015 ubi_devices[ubi_num] = ubi;
1016 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1017 return ubi_num;
1018
1019out_debugfs:
1020 ubi_debugfs_exit_dev(ubi);
1021out_uif:
1022 get_device(&ubi->dev);
1023 ubi_assert(ref);
1024 uif_close(ubi);
1025out_detach:
1026 ubi_wl_close(ubi);
1027 free_internal_volumes(ubi);
1028 vfree(ubi->vtbl);
1029out_debugging:
1030 ubi_debugging_exit_dev(ubi);
1031out_free:
1032 vfree(ubi->peb_buf1);
1033 vfree(ubi->peb_buf2);
1034 if (ref)
1035 put_device(&ubi->dev);
1036 else
1037 kfree(ubi);
1038 return err;
1039}
1040
1041/**
1042 * ubi_detach_mtd_dev - detach an MTD device.
1043 * @ubi_num: UBI device number to detach from
1044 * @anyway: detach MTD even if device reference count is not zero
1045 *
1046 * This function destroys an UBI device number @ubi_num and detaches the
1047 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1048 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1049 * exist.
1050 *
1051 * Note, the invocations of this function has to be serialized by the
1052 * @ubi_devices_mutex.
1053 */
1054int ubi_detach_mtd_dev(int ubi_num, int anyway)
1055{
1056 struct ubi_device *ubi;
1057
1058 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1059 return -EINVAL;
1060
1061 ubi = ubi_get_device(ubi_num);
1062 if (!ubi)
1063 return -EINVAL;
1064
1065 spin_lock(&ubi_devices_lock);
1066 put_device(&ubi->dev);
1067 ubi->ref_count -= 1;
1068 if (ubi->ref_count) {
1069 if (!anyway) {
1070 spin_unlock(&ubi_devices_lock);
1071 return -EBUSY;
1072 }
1073 /* This may only happen if there is a bug */
1074 ubi_err("%s reference count %d, destroy anyway",
1075 ubi->ubi_name, ubi->ref_count);
1076 }
1077 ubi_devices[ubi_num] = NULL;
1078 spin_unlock(&ubi_devices_lock);
1079
1080 ubi_assert(ubi_num == ubi->ubi_num);
1081 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1082 dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1083
1084 /*
1085 * Before freeing anything, we have to stop the background thread to
1086 * prevent it from doing anything on this device while we are freeing.
1087 */
1088 if (ubi->bgt_thread)
1089 kthread_stop(ubi->bgt_thread);
1090
1091 /*
1092 * Get a reference to the device in order to prevent 'dev_release()'
1093 * from freeing the @ubi object.
1094 */
1095 get_device(&ubi->dev);
1096
1097 ubi_debugfs_exit_dev(ubi);
1098 uif_close(ubi);
1099 ubi_wl_close(ubi);
1100 free_internal_volumes(ubi);
1101 vfree(ubi->vtbl);
1102 put_mtd_device(ubi->mtd);
1103 ubi_debugging_exit_dev(ubi);
1104 vfree(ubi->peb_buf1);
1105 vfree(ubi->peb_buf2);
1106 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1107 put_device(&ubi->dev);
1108 return 0;
1109}
1110
1111/**
1112 * open_mtd_by_chdev - open an MTD device by its character device node path.
1113 * @mtd_dev: MTD character device node path
1114 *
1115 * This helper function opens an MTD device by its character node device path.
1116 * Returns MTD device description object in case of success and a negative
1117 * error code in case of failure.
1118 */
1119static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1120{
1121 int err, major, minor, mode;
1122 struct path path;
1123
1124 /* Probably this is an MTD character device node path */
1125 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1126 if (err)
1127 return ERR_PTR(err);
1128
1129 /* MTD device number is defined by the major / minor numbers */
1130 major = imajor(path.dentry->d_inode);
1131 minor = iminor(path.dentry->d_inode);
1132 mode = path.dentry->d_inode->i_mode;
1133 path_put(&path);
1134 if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1135 return ERR_PTR(-EINVAL);
1136
1137 if (minor & 1)
1138 /*
1139 * Just do not think the "/dev/mtdrX" devices support is need,
1140 * so do not support them to avoid doing extra work.
1141 */
1142 return ERR_PTR(-EINVAL);
1143
1144 return get_mtd_device(NULL, minor / 2);
1145}
1146
1147/**
1148 * open_mtd_device - open MTD device by name, character device path, or number.
1149 * @mtd_dev: name, character device node path, or MTD device device number
1150 *
1151 * This function tries to open and MTD device described by @mtd_dev string,
1152 * which is first treated as ASCII MTD device number, and if it is not true, it
1153 * is treated as MTD device name, and if that is also not true, it is treated
1154 * as MTD character device node path. Returns MTD device description object in
1155 * case of success and a negative error code in case of failure.
1156 */
1157static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1158{
1159 struct mtd_info *mtd;
1160 int mtd_num;
1161 char *endp;
1162
1163 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1164 if (*endp != '\0' || mtd_dev == endp) {
1165 /*
1166 * This does not look like an ASCII integer, probably this is
1167 * MTD device name.
1168 */
1169 mtd = get_mtd_device_nm(mtd_dev);
1170 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1171 /* Probably this is an MTD character device node path */
1172 mtd = open_mtd_by_chdev(mtd_dev);
1173 } else
1174 mtd = get_mtd_device(NULL, mtd_num);
1175
1176 return mtd;
1177}
1178
1179static int __init ubi_init(void)
1180{
1181 int err, i, k;
1182
1183 /* Ensure that EC and VID headers have correct size */
1184 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1185 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1186
1187 if (mtd_devs > UBI_MAX_DEVICES) {
1188 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1189 return -EINVAL;
1190 }
1191
1192 /* Create base sysfs directory and sysfs files */
1193 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1194 if (IS_ERR(ubi_class)) {
1195 err = PTR_ERR(ubi_class);
1196 ubi_err("cannot create UBI class");
1197 goto out;
1198 }
1199
1200 err = class_create_file(ubi_class, &ubi_version);
1201 if (err) {
1202 ubi_err("cannot create sysfs file");
1203 goto out_class;
1204 }
1205
1206 err = misc_register(&ubi_ctrl_cdev);
1207 if (err) {
1208 ubi_err("cannot register device");
1209 goto out_version;
1210 }
1211
1212 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1213 sizeof(struct ubi_wl_entry),
1214 0, 0, NULL);
1215 if (!ubi_wl_entry_slab)
1216 goto out_dev_unreg;
1217
1218 err = ubi_debugfs_init();
1219 if (err)
1220 goto out_slab;
1221
1222
1223 /* Attach MTD devices */
1224 for (i = 0; i < mtd_devs; i++) {
1225 struct mtd_dev_param *p = &mtd_dev_param[i];
1226 struct mtd_info *mtd;
1227
1228 cond_resched();
1229
1230 mtd = open_mtd_device(p->name);
1231 if (IS_ERR(mtd)) {
1232 err = PTR_ERR(mtd);
1233 goto out_detach;
1234 }
1235
1236 mutex_lock(&ubi_devices_mutex);
1237 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
1238 p->vid_hdr_offs);
1239 mutex_unlock(&ubi_devices_mutex);
1240 if (err < 0) {
1241 ubi_err("cannot attach mtd%d", mtd->index);
1242 put_mtd_device(mtd);
1243
1244 /*
1245 * Originally UBI stopped initializing on any error.
1246 * However, later on it was found out that this
1247 * behavior is not very good when UBI is compiled into
1248 * the kernel and the MTD devices to attach are passed
1249 * through the command line. Indeed, UBI failure
1250 * stopped whole boot sequence.
1251 *
1252 * To fix this, we changed the behavior for the
1253 * non-module case, but preserved the old behavior for
1254 * the module case, just for compatibility. This is a
1255 * little inconsistent, though.
1256 */
1257 if (ubi_is_module())
1258 goto out_detach;
1259 }
1260 }
1261
1262 return 0;
1263
1264out_detach:
1265 for (k = 0; k < i; k++)
1266 if (ubi_devices[k]) {
1267 mutex_lock(&ubi_devices_mutex);
1268 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1269 mutex_unlock(&ubi_devices_mutex);
1270 }
1271 ubi_debugfs_exit();
1272out_slab:
1273 kmem_cache_destroy(ubi_wl_entry_slab);
1274out_dev_unreg:
1275 misc_deregister(&ubi_ctrl_cdev);
1276out_version:
1277 class_remove_file(ubi_class, &ubi_version);
1278out_class:
1279 class_destroy(ubi_class);
1280out:
1281 ubi_err("UBI error: cannot initialize UBI, error %d", err);
1282 return err;
1283}
1284module_init(ubi_init);
1285
1286static void __exit ubi_exit(void)
1287{
1288 int i;
1289
1290 for (i = 0; i < UBI_MAX_DEVICES; i++)
1291 if (ubi_devices[i]) {
1292 mutex_lock(&ubi_devices_mutex);
1293 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1294 mutex_unlock(&ubi_devices_mutex);
1295 }
1296 ubi_debugfs_exit();
1297 kmem_cache_destroy(ubi_wl_entry_slab);
1298 misc_deregister(&ubi_ctrl_cdev);
1299 class_remove_file(ubi_class, &ubi_version);
1300 class_destroy(ubi_class);
1301}
1302module_exit(ubi_exit);
1303
1304/**
1305 * bytes_str_to_int - convert a number of bytes string into an integer.
1306 * @str: the string to convert
1307 *
1308 * This function returns positive resulting integer in case of success and a
1309 * negative error code in case of failure.
1310 */
1311static int __init bytes_str_to_int(const char *str)
1312{
1313 char *endp;
1314 unsigned long result;
1315
1316 result = simple_strtoul(str, &endp, 0);
1317 if (str == endp || result >= INT_MAX) {
1318 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1319 str);
1320 return -EINVAL;
1321 }
1322
1323 switch (*endp) {
1324 case 'G':
1325 result *= 1024;
1326 case 'M':
1327 result *= 1024;
1328 case 'K':
1329 result *= 1024;
1330 if (endp[1] == 'i' && endp[2] == 'B')
1331 endp += 2;
1332 case '\0':
1333 break;
1334 default:
1335 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1336 str);
1337 return -EINVAL;
1338 }
1339
1340 return result;
1341}
1342
1343/**
1344 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1345 * @val: the parameter value to parse
1346 * @kp: not used
1347 *
1348 * This function returns zero in case of success and a negative error code in
1349 * case of error.
1350 */
1351static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1352{
1353 int i, len;
1354 struct mtd_dev_param *p;
1355 char buf[MTD_PARAM_LEN_MAX];
1356 char *pbuf = &buf[0];
1357 char *tokens[2] = {NULL, NULL};
1358
1359 if (!val)
1360 return -EINVAL;
1361
1362 if (mtd_devs == UBI_MAX_DEVICES) {
1363 printk(KERN_ERR "UBI error: too many parameters, max. is %d\n",
1364 UBI_MAX_DEVICES);
1365 return -EINVAL;
1366 }
1367
1368 len = strnlen(val, MTD_PARAM_LEN_MAX);
1369 if (len == MTD_PARAM_LEN_MAX) {
1370 printk(KERN_ERR "UBI error: parameter \"%s\" is too long, "
1371 "max. is %d\n", val, MTD_PARAM_LEN_MAX);
1372 return -EINVAL;
1373 }
1374
1375 if (len == 0) {
1376 printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - "
1377 "ignored\n");
1378 return 0;
1379 }
1380
1381 strcpy(buf, val);
1382
1383 /* Get rid of the final newline */
1384 if (buf[len - 1] == '\n')
1385 buf[len - 1] = '\0';
1386
1387 for (i = 0; i < 2; i++)
1388 tokens[i] = strsep(&pbuf, ",");
1389
1390 if (pbuf) {
1391 printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n",
1392 val);
1393 return -EINVAL;
1394 }
1395
1396 p = &mtd_dev_param[mtd_devs];
1397 strcpy(&p->name[0], tokens[0]);
1398
1399 if (tokens[1])
1400 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1401
1402 if (p->vid_hdr_offs < 0)
1403 return p->vid_hdr_offs;
1404
1405 mtd_devs += 1;
1406 return 0;
1407}
1408
1409module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1410MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1411 "mtd=<name|num|path>[,<vid_hdr_offs>].\n"
1412 "Multiple \"mtd\" parameters may be specified.\n"
1413 "MTD devices may be specified by their number, name, or "
1414 "path to the MTD character device node.\n"
1415 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1416 "header position to be used by UBI.\n"
1417 "Example 1: mtd=/dev/mtd0 - attach MTD device "
1418 "/dev/mtd0.\n"
1419 "Example 2: mtd=content,1984 mtd=4 - attach MTD device "
1420 "with name \"content\" using VID header offset 1984, and "
1421 "MTD device number 4 with default VID header offset.");
1422
1423MODULE_VERSION(__stringify(UBI_VERSION));
1424MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1425MODULE_AUTHOR("Artem Bityutskiy");
1426MODULE_LICENSE("GPL");
1/*
2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2007
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Author: Artem Bityutskiy (Битюцкий Артём),
20 * Frank Haverkamp
21 */
22
23/*
24 * This file includes UBI initialization and building of UBI devices.
25 *
26 * When UBI is initialized, it attaches all the MTD devices specified as the
27 * module load parameters or the kernel boot parameters. If MTD devices were
28 * specified, UBI does not attach any MTD device, but it is possible to do
29 * later using the "UBI control device".
30 */
31
32#include <linux/err.h>
33#include <linux/module.h>
34#include <linux/moduleparam.h>
35#include <linux/stringify.h>
36#include <linux/namei.h>
37#include <linux/stat.h>
38#include <linux/miscdevice.h>
39#include <linux/mtd/partitions.h>
40#include <linux/log2.h>
41#include <linux/kthread.h>
42#include <linux/kernel.h>
43#include <linux/slab.h>
44#include <linux/major.h>
45#include "ubi.h"
46
47/* Maximum length of the 'mtd=' parameter */
48#define MTD_PARAM_LEN_MAX 64
49
50/* Maximum number of comma-separated items in the 'mtd=' parameter */
51#define MTD_PARAM_MAX_COUNT 4
52
53/* Maximum value for the number of bad PEBs per 1024 PEBs */
54#define MAX_MTD_UBI_BEB_LIMIT 768
55
56#ifdef CONFIG_MTD_UBI_MODULE
57#define ubi_is_module() 1
58#else
59#define ubi_is_module() 0
60#endif
61
62/**
63 * struct mtd_dev_param - MTD device parameter description data structure.
64 * @name: MTD character device node path, MTD device name, or MTD device number
65 * string
66 * @vid_hdr_offs: VID header offset
67 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
68 */
69struct mtd_dev_param {
70 char name[MTD_PARAM_LEN_MAX];
71 int ubi_num;
72 int vid_hdr_offs;
73 int max_beb_per1024;
74};
75
76/* Numbers of elements set in the @mtd_dev_param array */
77static int mtd_devs;
78
79/* MTD devices specification parameters */
80static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
81#ifdef CONFIG_MTD_UBI_FASTMAP
82/* UBI module parameter to enable fastmap automatically on non-fastmap images */
83static bool fm_autoconvert;
84static bool fm_debug;
85#endif
86
87/* Slab cache for wear-leveling entries */
88struct kmem_cache *ubi_wl_entry_slab;
89
90/* UBI control character device */
91static struct miscdevice ubi_ctrl_cdev = {
92 .minor = MISC_DYNAMIC_MINOR,
93 .name = "ubi_ctrl",
94 .fops = &ubi_ctrl_cdev_operations,
95};
96
97/* All UBI devices in system */
98static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
99
100/* Serializes UBI devices creations and removals */
101DEFINE_MUTEX(ubi_devices_mutex);
102
103/* Protects @ubi_devices and @ubi->ref_count */
104static DEFINE_SPINLOCK(ubi_devices_lock);
105
106/* "Show" method for files in '/<sysfs>/class/ubi/' */
107/* UBI version attribute ('/<sysfs>/class/ubi/version') */
108static ssize_t version_show(struct class *class, struct class_attribute *attr,
109 char *buf)
110{
111 return sprintf(buf, "%d\n", UBI_VERSION);
112}
113static CLASS_ATTR_RO(version);
114
115static struct attribute *ubi_class_attrs[] = {
116 &class_attr_version.attr,
117 NULL,
118};
119ATTRIBUTE_GROUPS(ubi_class);
120
121/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
122struct class ubi_class = {
123 .name = UBI_NAME_STR,
124 .owner = THIS_MODULE,
125 .class_groups = ubi_class_groups,
126};
127
128static ssize_t dev_attribute_show(struct device *dev,
129 struct device_attribute *attr, char *buf);
130
131/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
132static struct device_attribute dev_eraseblock_size =
133 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
134static struct device_attribute dev_avail_eraseblocks =
135 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
136static struct device_attribute dev_total_eraseblocks =
137 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
138static struct device_attribute dev_volumes_count =
139 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
140static struct device_attribute dev_max_ec =
141 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
142static struct device_attribute dev_reserved_for_bad =
143 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
144static struct device_attribute dev_bad_peb_count =
145 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
146static struct device_attribute dev_max_vol_count =
147 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
148static struct device_attribute dev_min_io_size =
149 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
150static struct device_attribute dev_bgt_enabled =
151 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
152static struct device_attribute dev_mtd_num =
153 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
154static struct device_attribute dev_ro_mode =
155 __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
156
157/**
158 * ubi_volume_notify - send a volume change notification.
159 * @ubi: UBI device description object
160 * @vol: volume description object of the changed volume
161 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
162 *
163 * This is a helper function which notifies all subscribers about a volume
164 * change event (creation, removal, re-sizing, re-naming, updating). Returns
165 * zero in case of success and a negative error code in case of failure.
166 */
167int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
168{
169 int ret;
170 struct ubi_notification nt;
171
172 ubi_do_get_device_info(ubi, &nt.di);
173 ubi_do_get_volume_info(ubi, vol, &nt.vi);
174
175 switch (ntype) {
176 case UBI_VOLUME_ADDED:
177 case UBI_VOLUME_REMOVED:
178 case UBI_VOLUME_RESIZED:
179 case UBI_VOLUME_RENAMED:
180 ret = ubi_update_fastmap(ubi);
181 if (ret)
182 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
183 }
184
185 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
186}
187
188/**
189 * ubi_notify_all - send a notification to all volumes.
190 * @ubi: UBI device description object
191 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
192 * @nb: the notifier to call
193 *
194 * This function walks all volumes of UBI device @ubi and sends the @ntype
195 * notification for each volume. If @nb is %NULL, then all registered notifiers
196 * are called, otherwise only the @nb notifier is called. Returns the number of
197 * sent notifications.
198 */
199int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
200{
201 struct ubi_notification nt;
202 int i, count = 0;
203
204 ubi_do_get_device_info(ubi, &nt.di);
205
206 mutex_lock(&ubi->device_mutex);
207 for (i = 0; i < ubi->vtbl_slots; i++) {
208 /*
209 * Since the @ubi->device is locked, and we are not going to
210 * change @ubi->volumes, we do not have to lock
211 * @ubi->volumes_lock.
212 */
213 if (!ubi->volumes[i])
214 continue;
215
216 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
217 if (nb)
218 nb->notifier_call(nb, ntype, &nt);
219 else
220 blocking_notifier_call_chain(&ubi_notifiers, ntype,
221 &nt);
222 count += 1;
223 }
224 mutex_unlock(&ubi->device_mutex);
225
226 return count;
227}
228
229/**
230 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
231 * @nb: the notifier to call
232 *
233 * This function walks all UBI devices and volumes and sends the
234 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
235 * registered notifiers are called, otherwise only the @nb notifier is called.
236 * Returns the number of sent notifications.
237 */
238int ubi_enumerate_volumes(struct notifier_block *nb)
239{
240 int i, count = 0;
241
242 /*
243 * Since the @ubi_devices_mutex is locked, and we are not going to
244 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
245 */
246 for (i = 0; i < UBI_MAX_DEVICES; i++) {
247 struct ubi_device *ubi = ubi_devices[i];
248
249 if (!ubi)
250 continue;
251 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
252 }
253
254 return count;
255}
256
257/**
258 * ubi_get_device - get UBI device.
259 * @ubi_num: UBI device number
260 *
261 * This function returns UBI device description object for UBI device number
262 * @ubi_num, or %NULL if the device does not exist. This function increases the
263 * device reference count to prevent removal of the device. In other words, the
264 * device cannot be removed if its reference count is not zero.
265 */
266struct ubi_device *ubi_get_device(int ubi_num)
267{
268 struct ubi_device *ubi;
269
270 spin_lock(&ubi_devices_lock);
271 ubi = ubi_devices[ubi_num];
272 if (ubi) {
273 ubi_assert(ubi->ref_count >= 0);
274 ubi->ref_count += 1;
275 get_device(&ubi->dev);
276 }
277 spin_unlock(&ubi_devices_lock);
278
279 return ubi;
280}
281
282/**
283 * ubi_put_device - drop an UBI device reference.
284 * @ubi: UBI device description object
285 */
286void ubi_put_device(struct ubi_device *ubi)
287{
288 spin_lock(&ubi_devices_lock);
289 ubi->ref_count -= 1;
290 put_device(&ubi->dev);
291 spin_unlock(&ubi_devices_lock);
292}
293
294/**
295 * ubi_get_by_major - get UBI device by character device major number.
296 * @major: major number
297 *
298 * This function is similar to 'ubi_get_device()', but it searches the device
299 * by its major number.
300 */
301struct ubi_device *ubi_get_by_major(int major)
302{
303 int i;
304 struct ubi_device *ubi;
305
306 spin_lock(&ubi_devices_lock);
307 for (i = 0; i < UBI_MAX_DEVICES; i++) {
308 ubi = ubi_devices[i];
309 if (ubi && MAJOR(ubi->cdev.dev) == major) {
310 ubi_assert(ubi->ref_count >= 0);
311 ubi->ref_count += 1;
312 get_device(&ubi->dev);
313 spin_unlock(&ubi_devices_lock);
314 return ubi;
315 }
316 }
317 spin_unlock(&ubi_devices_lock);
318
319 return NULL;
320}
321
322/**
323 * ubi_major2num - get UBI device number by character device major number.
324 * @major: major number
325 *
326 * This function searches UBI device number object by its major number. If UBI
327 * device was not found, this function returns -ENODEV, otherwise the UBI device
328 * number is returned.
329 */
330int ubi_major2num(int major)
331{
332 int i, ubi_num = -ENODEV;
333
334 spin_lock(&ubi_devices_lock);
335 for (i = 0; i < UBI_MAX_DEVICES; i++) {
336 struct ubi_device *ubi = ubi_devices[i];
337
338 if (ubi && MAJOR(ubi->cdev.dev) == major) {
339 ubi_num = ubi->ubi_num;
340 break;
341 }
342 }
343 spin_unlock(&ubi_devices_lock);
344
345 return ubi_num;
346}
347
348/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
349static ssize_t dev_attribute_show(struct device *dev,
350 struct device_attribute *attr, char *buf)
351{
352 ssize_t ret;
353 struct ubi_device *ubi;
354
355 /*
356 * The below code looks weird, but it actually makes sense. We get the
357 * UBI device reference from the contained 'struct ubi_device'. But it
358 * is unclear if the device was removed or not yet. Indeed, if the
359 * device was removed before we increased its reference count,
360 * 'ubi_get_device()' will return -ENODEV and we fail.
361 *
362 * Remember, 'struct ubi_device' is freed in the release function, so
363 * we still can use 'ubi->ubi_num'.
364 */
365 ubi = container_of(dev, struct ubi_device, dev);
366 ubi = ubi_get_device(ubi->ubi_num);
367 if (!ubi)
368 return -ENODEV;
369
370 if (attr == &dev_eraseblock_size)
371 ret = sprintf(buf, "%d\n", ubi->leb_size);
372 else if (attr == &dev_avail_eraseblocks)
373 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
374 else if (attr == &dev_total_eraseblocks)
375 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
376 else if (attr == &dev_volumes_count)
377 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
378 else if (attr == &dev_max_ec)
379 ret = sprintf(buf, "%d\n", ubi->max_ec);
380 else if (attr == &dev_reserved_for_bad)
381 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
382 else if (attr == &dev_bad_peb_count)
383 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
384 else if (attr == &dev_max_vol_count)
385 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
386 else if (attr == &dev_min_io_size)
387 ret = sprintf(buf, "%d\n", ubi->min_io_size);
388 else if (attr == &dev_bgt_enabled)
389 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
390 else if (attr == &dev_mtd_num)
391 ret = sprintf(buf, "%d\n", ubi->mtd->index);
392 else if (attr == &dev_ro_mode)
393 ret = sprintf(buf, "%d\n", ubi->ro_mode);
394 else
395 ret = -EINVAL;
396
397 ubi_put_device(ubi);
398 return ret;
399}
400
401static struct attribute *ubi_dev_attrs[] = {
402 &dev_eraseblock_size.attr,
403 &dev_avail_eraseblocks.attr,
404 &dev_total_eraseblocks.attr,
405 &dev_volumes_count.attr,
406 &dev_max_ec.attr,
407 &dev_reserved_for_bad.attr,
408 &dev_bad_peb_count.attr,
409 &dev_max_vol_count.attr,
410 &dev_min_io_size.attr,
411 &dev_bgt_enabled.attr,
412 &dev_mtd_num.attr,
413 &dev_ro_mode.attr,
414 NULL
415};
416ATTRIBUTE_GROUPS(ubi_dev);
417
418static void dev_release(struct device *dev)
419{
420 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
421
422 kfree(ubi);
423}
424
425/**
426 * kill_volumes - destroy all user volumes.
427 * @ubi: UBI device description object
428 */
429static void kill_volumes(struct ubi_device *ubi)
430{
431 int i;
432
433 for (i = 0; i < ubi->vtbl_slots; i++)
434 if (ubi->volumes[i])
435 ubi_free_volume(ubi, ubi->volumes[i]);
436}
437
438/**
439 * uif_init - initialize user interfaces for an UBI device.
440 * @ubi: UBI device description object
441 *
442 * This function initializes various user interfaces for an UBI device. If the
443 * initialization fails at an early stage, this function frees all the
444 * resources it allocated, returns an error.
445 *
446 * This function returns zero in case of success and a negative error code in
447 * case of failure.
448 */
449static int uif_init(struct ubi_device *ubi)
450{
451 int i, err;
452 dev_t dev;
453
454 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
455
456 /*
457 * Major numbers for the UBI character devices are allocated
458 * dynamically. Major numbers of volume character devices are
459 * equivalent to ones of the corresponding UBI character device. Minor
460 * numbers of UBI character devices are 0, while minor numbers of
461 * volume character devices start from 1. Thus, we allocate one major
462 * number and ubi->vtbl_slots + 1 minor numbers.
463 */
464 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
465 if (err) {
466 ubi_err(ubi, "cannot register UBI character devices");
467 return err;
468 }
469
470 ubi->dev.devt = dev;
471
472 ubi_assert(MINOR(dev) == 0);
473 cdev_init(&ubi->cdev, &ubi_cdev_operations);
474 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
475 ubi->cdev.owner = THIS_MODULE;
476
477 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
478 err = cdev_device_add(&ubi->cdev, &ubi->dev);
479 if (err)
480 goto out_unreg;
481
482 for (i = 0; i < ubi->vtbl_slots; i++)
483 if (ubi->volumes[i]) {
484 err = ubi_add_volume(ubi, ubi->volumes[i]);
485 if (err) {
486 ubi_err(ubi, "cannot add volume %d", i);
487 goto out_volumes;
488 }
489 }
490
491 return 0;
492
493out_volumes:
494 kill_volumes(ubi);
495 cdev_device_del(&ubi->cdev, &ubi->dev);
496out_unreg:
497 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
498 ubi_err(ubi, "cannot initialize UBI %s, error %d",
499 ubi->ubi_name, err);
500 return err;
501}
502
503/**
504 * uif_close - close user interfaces for an UBI device.
505 * @ubi: UBI device description object
506 *
507 * Note, since this function un-registers UBI volume device objects (@vol->dev),
508 * the memory allocated voe the volumes is freed as well (in the release
509 * function).
510 */
511static void uif_close(struct ubi_device *ubi)
512{
513 kill_volumes(ubi);
514 cdev_device_del(&ubi->cdev, &ubi->dev);
515 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
516}
517
518/**
519 * ubi_free_internal_volumes - free internal volumes.
520 * @ubi: UBI device description object
521 */
522void ubi_free_internal_volumes(struct ubi_device *ubi)
523{
524 int i;
525
526 for (i = ubi->vtbl_slots;
527 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
528 ubi_eba_replace_table(ubi->volumes[i], NULL);
529 kfree(ubi->volumes[i]);
530 }
531}
532
533static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
534{
535 int limit, device_pebs;
536 uint64_t device_size;
537
538 if (!max_beb_per1024) {
539 /*
540 * Since max_beb_per1024 has not been set by the user in either
541 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the
542 * limit if it is supported by the device.
543 */
544 limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size);
545 if (limit < 0)
546 return 0;
547 return limit;
548 }
549
550 /*
551 * Here we are using size of the entire flash chip and
552 * not just the MTD partition size because the maximum
553 * number of bad eraseblocks is a percentage of the
554 * whole device and bad eraseblocks are not fairly
555 * distributed over the flash chip. So the worst case
556 * is that all the bad eraseblocks of the chip are in
557 * the MTD partition we are attaching (ubi->mtd).
558 */
559 device_size = mtd_get_device_size(ubi->mtd);
560 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
561 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
562
563 /* Round it up */
564 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
565 limit += 1;
566
567 return limit;
568}
569
570/**
571 * io_init - initialize I/O sub-system for a given UBI device.
572 * @ubi: UBI device description object
573 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
574 *
575 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
576 * assumed:
577 * o EC header is always at offset zero - this cannot be changed;
578 * o VID header starts just after the EC header at the closest address
579 * aligned to @io->hdrs_min_io_size;
580 * o data starts just after the VID header at the closest address aligned to
581 * @io->min_io_size
582 *
583 * This function returns zero in case of success and a negative error code in
584 * case of failure.
585 */
586static int io_init(struct ubi_device *ubi, int max_beb_per1024)
587{
588 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
589 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
590
591 if (ubi->mtd->numeraseregions != 0) {
592 /*
593 * Some flashes have several erase regions. Different regions
594 * may have different eraseblock size and other
595 * characteristics. It looks like mostly multi-region flashes
596 * have one "main" region and one or more small regions to
597 * store boot loader code or boot parameters or whatever. I
598 * guess we should just pick the largest region. But this is
599 * not implemented.
600 */
601 ubi_err(ubi, "multiple regions, not implemented");
602 return -EINVAL;
603 }
604
605 if (ubi->vid_hdr_offset < 0)
606 return -EINVAL;
607
608 /*
609 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
610 * physical eraseblocks maximum.
611 */
612
613 ubi->peb_size = ubi->mtd->erasesize;
614 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
615 ubi->flash_size = ubi->mtd->size;
616
617 if (mtd_can_have_bb(ubi->mtd)) {
618 ubi->bad_allowed = 1;
619 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
620 }
621
622 if (ubi->mtd->type == MTD_NORFLASH) {
623 ubi_assert(ubi->mtd->writesize == 1);
624 ubi->nor_flash = 1;
625 }
626
627 ubi->min_io_size = ubi->mtd->writesize;
628 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
629
630 /*
631 * Make sure minimal I/O unit is power of 2. Note, there is no
632 * fundamental reason for this assumption. It is just an optimization
633 * which allows us to avoid costly division operations.
634 */
635 if (!is_power_of_2(ubi->min_io_size)) {
636 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
637 ubi->min_io_size);
638 return -EINVAL;
639 }
640
641 ubi_assert(ubi->hdrs_min_io_size > 0);
642 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
643 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
644
645 ubi->max_write_size = ubi->mtd->writebufsize;
646 /*
647 * Maximum write size has to be greater or equivalent to min. I/O
648 * size, and be multiple of min. I/O size.
649 */
650 if (ubi->max_write_size < ubi->min_io_size ||
651 ubi->max_write_size % ubi->min_io_size ||
652 !is_power_of_2(ubi->max_write_size)) {
653 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
654 ubi->max_write_size, ubi->min_io_size);
655 return -EINVAL;
656 }
657
658 /* Calculate default aligned sizes of EC and VID headers */
659 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
660 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
661
662 dbg_gen("min_io_size %d", ubi->min_io_size);
663 dbg_gen("max_write_size %d", ubi->max_write_size);
664 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
665 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
666 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
667
668 if (ubi->vid_hdr_offset == 0)
669 /* Default offset */
670 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
671 ubi->ec_hdr_alsize;
672 else {
673 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
674 ~(ubi->hdrs_min_io_size - 1);
675 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
676 ubi->vid_hdr_aloffset;
677 }
678
679 /* Similar for the data offset */
680 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
681 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
682
683 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
684 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
685 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
686 dbg_gen("leb_start %d", ubi->leb_start);
687
688 /* The shift must be aligned to 32-bit boundary */
689 if (ubi->vid_hdr_shift % 4) {
690 ubi_err(ubi, "unaligned VID header shift %d",
691 ubi->vid_hdr_shift);
692 return -EINVAL;
693 }
694
695 /* Check sanity */
696 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
697 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
698 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
699 ubi->leb_start & (ubi->min_io_size - 1)) {
700 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
701 ubi->vid_hdr_offset, ubi->leb_start);
702 return -EINVAL;
703 }
704
705 /*
706 * Set maximum amount of physical erroneous eraseblocks to be 10%.
707 * Erroneous PEB are those which have read errors.
708 */
709 ubi->max_erroneous = ubi->peb_count / 10;
710 if (ubi->max_erroneous < 16)
711 ubi->max_erroneous = 16;
712 dbg_gen("max_erroneous %d", ubi->max_erroneous);
713
714 /*
715 * It may happen that EC and VID headers are situated in one minimal
716 * I/O unit. In this case we can only accept this UBI image in
717 * read-only mode.
718 */
719 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
720 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
721 ubi->ro_mode = 1;
722 }
723
724 ubi->leb_size = ubi->peb_size - ubi->leb_start;
725
726 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
727 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
728 ubi->mtd->index);
729 ubi->ro_mode = 1;
730 }
731
732 /*
733 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
734 * unfortunately, MTD does not provide this information. We should loop
735 * over all physical eraseblocks and invoke mtd->block_is_bad() for
736 * each physical eraseblock. So, we leave @ubi->bad_peb_count
737 * uninitialized so far.
738 */
739
740 return 0;
741}
742
743/**
744 * autoresize - re-size the volume which has the "auto-resize" flag set.
745 * @ubi: UBI device description object
746 * @vol_id: ID of the volume to re-size
747 *
748 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
749 * the volume table to the largest possible size. See comments in ubi-header.h
750 * for more description of the flag. Returns zero in case of success and a
751 * negative error code in case of failure.
752 */
753static int autoresize(struct ubi_device *ubi, int vol_id)
754{
755 struct ubi_volume_desc desc;
756 struct ubi_volume *vol = ubi->volumes[vol_id];
757 int err, old_reserved_pebs = vol->reserved_pebs;
758
759 if (ubi->ro_mode) {
760 ubi_warn(ubi, "skip auto-resize because of R/O mode");
761 return 0;
762 }
763
764 /*
765 * Clear the auto-resize flag in the volume in-memory copy of the
766 * volume table, and 'ubi_resize_volume()' will propagate this change
767 * to the flash.
768 */
769 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
770
771 if (ubi->avail_pebs == 0) {
772 struct ubi_vtbl_record vtbl_rec;
773
774 /*
775 * No available PEBs to re-size the volume, clear the flag on
776 * flash and exit.
777 */
778 vtbl_rec = ubi->vtbl[vol_id];
779 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
780 if (err)
781 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
782 vol_id);
783 } else {
784 desc.vol = vol;
785 err = ubi_resize_volume(&desc,
786 old_reserved_pebs + ubi->avail_pebs);
787 if (err)
788 ubi_err(ubi, "cannot auto-resize volume %d",
789 vol_id);
790 }
791
792 if (err)
793 return err;
794
795 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
796 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
797 return 0;
798}
799
800/**
801 * ubi_attach_mtd_dev - attach an MTD device.
802 * @mtd: MTD device description object
803 * @ubi_num: number to assign to the new UBI device
804 * @vid_hdr_offset: VID header offset
805 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
806 *
807 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
808 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
809 * which case this function finds a vacant device number and assigns it
810 * automatically. Returns the new UBI device number in case of success and a
811 * negative error code in case of failure.
812 *
813 * Note, the invocations of this function has to be serialized by the
814 * @ubi_devices_mutex.
815 */
816int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
817 int vid_hdr_offset, int max_beb_per1024)
818{
819 struct ubi_device *ubi;
820 int i, err;
821
822 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
823 return -EINVAL;
824
825 if (!max_beb_per1024)
826 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
827
828 /*
829 * Check if we already have the same MTD device attached.
830 *
831 * Note, this function assumes that UBI devices creations and deletions
832 * are serialized, so it does not take the &ubi_devices_lock.
833 */
834 for (i = 0; i < UBI_MAX_DEVICES; i++) {
835 ubi = ubi_devices[i];
836 if (ubi && mtd->index == ubi->mtd->index) {
837 pr_err("ubi: mtd%d is already attached to ubi%d\n",
838 mtd->index, i);
839 return -EEXIST;
840 }
841 }
842
843 /*
844 * Make sure this MTD device is not emulated on top of an UBI volume
845 * already. Well, generally this recursion works fine, but there are
846 * different problems like the UBI module takes a reference to itself
847 * by attaching (and thus, opening) the emulated MTD device. This
848 * results in inability to unload the module. And in general it makes
849 * no sense to attach emulated MTD devices, so we prohibit this.
850 */
851 if (mtd->type == MTD_UBIVOLUME) {
852 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",
853 mtd->index);
854 return -EINVAL;
855 }
856
857 /*
858 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
859 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
860 * will die soon and you will lose all your data.
861 */
862 if (mtd->type == MTD_MLCNANDFLASH) {
863 pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
864 mtd->index);
865 return -EINVAL;
866 }
867
868 if (ubi_num == UBI_DEV_NUM_AUTO) {
869 /* Search for an empty slot in the @ubi_devices array */
870 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
871 if (!ubi_devices[ubi_num])
872 break;
873 if (ubi_num == UBI_MAX_DEVICES) {
874 pr_err("ubi: only %d UBI devices may be created\n",
875 UBI_MAX_DEVICES);
876 return -ENFILE;
877 }
878 } else {
879 if (ubi_num >= UBI_MAX_DEVICES)
880 return -EINVAL;
881
882 /* Make sure ubi_num is not busy */
883 if (ubi_devices[ubi_num]) {
884 pr_err("ubi: ubi%i already exists\n", ubi_num);
885 return -EEXIST;
886 }
887 }
888
889 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
890 if (!ubi)
891 return -ENOMEM;
892
893 device_initialize(&ubi->dev);
894 ubi->dev.release = dev_release;
895 ubi->dev.class = &ubi_class;
896 ubi->dev.groups = ubi_dev_groups;
897
898 ubi->mtd = mtd;
899 ubi->ubi_num = ubi_num;
900 ubi->vid_hdr_offset = vid_hdr_offset;
901 ubi->autoresize_vol_id = -1;
902
903#ifdef CONFIG_MTD_UBI_FASTMAP
904 ubi->fm_pool.used = ubi->fm_pool.size = 0;
905 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
906
907 /*
908 * fm_pool.max_size is 5% of the total number of PEBs but it's also
909 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
910 */
911 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
912 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
913 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
914 UBI_FM_MIN_POOL_SIZE);
915
916 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
917 ubi->fm_disabled = !fm_autoconvert;
918 if (fm_debug)
919 ubi_enable_dbg_chk_fastmap(ubi);
920
921 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
922 <= UBI_FM_MAX_START) {
923 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
924 UBI_FM_MAX_START);
925 ubi->fm_disabled = 1;
926 }
927
928 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
929 ubi_msg(ubi, "default fastmap WL pool size: %d",
930 ubi->fm_wl_pool.max_size);
931#else
932 ubi->fm_disabled = 1;
933#endif
934 mutex_init(&ubi->buf_mutex);
935 mutex_init(&ubi->ckvol_mutex);
936 mutex_init(&ubi->device_mutex);
937 spin_lock_init(&ubi->volumes_lock);
938 init_rwsem(&ubi->fm_protect);
939 init_rwsem(&ubi->fm_eba_sem);
940
941 ubi_msg(ubi, "attaching mtd%d", mtd->index);
942
943 err = io_init(ubi, max_beb_per1024);
944 if (err)
945 goto out_free;
946
947 err = -ENOMEM;
948 ubi->peb_buf = vmalloc(ubi->peb_size);
949 if (!ubi->peb_buf)
950 goto out_free;
951
952#ifdef CONFIG_MTD_UBI_FASTMAP
953 ubi->fm_size = ubi_calc_fm_size(ubi);
954 ubi->fm_buf = vzalloc(ubi->fm_size);
955 if (!ubi->fm_buf)
956 goto out_free;
957#endif
958 err = ubi_attach(ubi, 0);
959 if (err) {
960 ubi_err(ubi, "failed to attach mtd%d, error %d",
961 mtd->index, err);
962 goto out_free;
963 }
964
965 if (ubi->autoresize_vol_id != -1) {
966 err = autoresize(ubi, ubi->autoresize_vol_id);
967 if (err)
968 goto out_detach;
969 }
970
971 /* Make device "available" before it becomes accessible via sysfs */
972 ubi_devices[ubi_num] = ubi;
973
974 err = uif_init(ubi);
975 if (err)
976 goto out_detach;
977
978 err = ubi_debugfs_init_dev(ubi);
979 if (err)
980 goto out_uif;
981
982 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
983 if (IS_ERR(ubi->bgt_thread)) {
984 err = PTR_ERR(ubi->bgt_thread);
985 ubi_err(ubi, "cannot spawn \"%s\", error %d",
986 ubi->bgt_name, err);
987 goto out_debugfs;
988 }
989
990 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
991 mtd->index, mtd->name, ubi->flash_size >> 20);
992 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
993 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
994 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
995 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
996 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
997 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
998 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
999 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1000 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
1001 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
1002 ubi->vtbl_slots);
1003 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1004 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1005 ubi->image_seq);
1006 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1007 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1008
1009 /*
1010 * The below lock makes sure we do not race with 'ubi_thread()' which
1011 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1012 */
1013 spin_lock(&ubi->wl_lock);
1014 ubi->thread_enabled = 1;
1015 wake_up_process(ubi->bgt_thread);
1016 spin_unlock(&ubi->wl_lock);
1017
1018 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1019 return ubi_num;
1020
1021out_debugfs:
1022 ubi_debugfs_exit_dev(ubi);
1023out_uif:
1024 uif_close(ubi);
1025out_detach:
1026 ubi_devices[ubi_num] = NULL;
1027 ubi_wl_close(ubi);
1028 ubi_free_internal_volumes(ubi);
1029 vfree(ubi->vtbl);
1030out_free:
1031 vfree(ubi->peb_buf);
1032 vfree(ubi->fm_buf);
1033 put_device(&ubi->dev);
1034 return err;
1035}
1036
1037/**
1038 * ubi_detach_mtd_dev - detach an MTD device.
1039 * @ubi_num: UBI device number to detach from
1040 * @anyway: detach MTD even if device reference count is not zero
1041 *
1042 * This function destroys an UBI device number @ubi_num and detaches the
1043 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1044 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1045 * exist.
1046 *
1047 * Note, the invocations of this function has to be serialized by the
1048 * @ubi_devices_mutex.
1049 */
1050int ubi_detach_mtd_dev(int ubi_num, int anyway)
1051{
1052 struct ubi_device *ubi;
1053
1054 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1055 return -EINVAL;
1056
1057 ubi = ubi_get_device(ubi_num);
1058 if (!ubi)
1059 return -EINVAL;
1060
1061 spin_lock(&ubi_devices_lock);
1062 put_device(&ubi->dev);
1063 ubi->ref_count -= 1;
1064 if (ubi->ref_count) {
1065 if (!anyway) {
1066 spin_unlock(&ubi_devices_lock);
1067 return -EBUSY;
1068 }
1069 /* This may only happen if there is a bug */
1070 ubi_err(ubi, "%s reference count %d, destroy anyway",
1071 ubi->ubi_name, ubi->ref_count);
1072 }
1073 ubi_devices[ubi_num] = NULL;
1074 spin_unlock(&ubi_devices_lock);
1075
1076 ubi_assert(ubi_num == ubi->ubi_num);
1077 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1078 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1079#ifdef CONFIG_MTD_UBI_FASTMAP
1080 /* If we don't write a new fastmap at detach time we lose all
1081 * EC updates that have been made since the last written fastmap.
1082 * In case of fastmap debugging we omit the update to simulate an
1083 * unclean shutdown. */
1084 if (!ubi_dbg_chk_fastmap(ubi))
1085 ubi_update_fastmap(ubi);
1086#endif
1087 /*
1088 * Before freeing anything, we have to stop the background thread to
1089 * prevent it from doing anything on this device while we are freeing.
1090 */
1091 if (ubi->bgt_thread)
1092 kthread_stop(ubi->bgt_thread);
1093
1094 ubi_debugfs_exit_dev(ubi);
1095 uif_close(ubi);
1096
1097 ubi_wl_close(ubi);
1098 ubi_free_internal_volumes(ubi);
1099 vfree(ubi->vtbl);
1100 put_mtd_device(ubi->mtd);
1101 vfree(ubi->peb_buf);
1102 vfree(ubi->fm_buf);
1103 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1104 put_device(&ubi->dev);
1105 return 0;
1106}
1107
1108/**
1109 * open_mtd_by_chdev - open an MTD device by its character device node path.
1110 * @mtd_dev: MTD character device node path
1111 *
1112 * This helper function opens an MTD device by its character node device path.
1113 * Returns MTD device description object in case of success and a negative
1114 * error code in case of failure.
1115 */
1116static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1117{
1118 int err, minor;
1119 struct path path;
1120 struct kstat stat;
1121
1122 /* Probably this is an MTD character device node path */
1123 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1124 if (err)
1125 return ERR_PTR(err);
1126
1127 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1128 path_put(&path);
1129 if (err)
1130 return ERR_PTR(err);
1131
1132 /* MTD device number is defined by the major / minor numbers */
1133 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1134 return ERR_PTR(-EINVAL);
1135
1136 minor = MINOR(stat.rdev);
1137
1138 if (minor & 1)
1139 /*
1140 * Just do not think the "/dev/mtdrX" devices support is need,
1141 * so do not support them to avoid doing extra work.
1142 */
1143 return ERR_PTR(-EINVAL);
1144
1145 return get_mtd_device(NULL, minor / 2);
1146}
1147
1148/**
1149 * open_mtd_device - open MTD device by name, character device path, or number.
1150 * @mtd_dev: name, character device node path, or MTD device device number
1151 *
1152 * This function tries to open and MTD device described by @mtd_dev string,
1153 * which is first treated as ASCII MTD device number, and if it is not true, it
1154 * is treated as MTD device name, and if that is also not true, it is treated
1155 * as MTD character device node path. Returns MTD device description object in
1156 * case of success and a negative error code in case of failure.
1157 */
1158static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1159{
1160 struct mtd_info *mtd;
1161 int mtd_num;
1162 char *endp;
1163
1164 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1165 if (*endp != '\0' || mtd_dev == endp) {
1166 /*
1167 * This does not look like an ASCII integer, probably this is
1168 * MTD device name.
1169 */
1170 mtd = get_mtd_device_nm(mtd_dev);
1171 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1172 /* Probably this is an MTD character device node path */
1173 mtd = open_mtd_by_chdev(mtd_dev);
1174 } else
1175 mtd = get_mtd_device(NULL, mtd_num);
1176
1177 return mtd;
1178}
1179
1180static int __init ubi_init(void)
1181{
1182 int err, i, k;
1183
1184 /* Ensure that EC and VID headers have correct size */
1185 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1186 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1187
1188 if (mtd_devs > UBI_MAX_DEVICES) {
1189 pr_err("UBI error: too many MTD devices, maximum is %d\n",
1190 UBI_MAX_DEVICES);
1191 return -EINVAL;
1192 }
1193
1194 /* Create base sysfs directory and sysfs files */
1195 err = class_register(&ubi_class);
1196 if (err < 0)
1197 return err;
1198
1199 err = misc_register(&ubi_ctrl_cdev);
1200 if (err) {
1201 pr_err("UBI error: cannot register device\n");
1202 goto out;
1203 }
1204
1205 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1206 sizeof(struct ubi_wl_entry),
1207 0, 0, NULL);
1208 if (!ubi_wl_entry_slab) {
1209 err = -ENOMEM;
1210 goto out_dev_unreg;
1211 }
1212
1213 err = ubi_debugfs_init();
1214 if (err)
1215 goto out_slab;
1216
1217
1218 /* Attach MTD devices */
1219 for (i = 0; i < mtd_devs; i++) {
1220 struct mtd_dev_param *p = &mtd_dev_param[i];
1221 struct mtd_info *mtd;
1222
1223 cond_resched();
1224
1225 mtd = open_mtd_device(p->name);
1226 if (IS_ERR(mtd)) {
1227 err = PTR_ERR(mtd);
1228 pr_err("UBI error: cannot open mtd %s, error %d\n",
1229 p->name, err);
1230 /* See comment below re-ubi_is_module(). */
1231 if (ubi_is_module())
1232 goto out_detach;
1233 continue;
1234 }
1235
1236 mutex_lock(&ubi_devices_mutex);
1237 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1238 p->vid_hdr_offs, p->max_beb_per1024);
1239 mutex_unlock(&ubi_devices_mutex);
1240 if (err < 0) {
1241 pr_err("UBI error: cannot attach mtd%d\n",
1242 mtd->index);
1243 put_mtd_device(mtd);
1244
1245 /*
1246 * Originally UBI stopped initializing on any error.
1247 * However, later on it was found out that this
1248 * behavior is not very good when UBI is compiled into
1249 * the kernel and the MTD devices to attach are passed
1250 * through the command line. Indeed, UBI failure
1251 * stopped whole boot sequence.
1252 *
1253 * To fix this, we changed the behavior for the
1254 * non-module case, but preserved the old behavior for
1255 * the module case, just for compatibility. This is a
1256 * little inconsistent, though.
1257 */
1258 if (ubi_is_module())
1259 goto out_detach;
1260 }
1261 }
1262
1263 err = ubiblock_init();
1264 if (err) {
1265 pr_err("UBI error: block: cannot initialize, error %d\n", err);
1266
1267 /* See comment above re-ubi_is_module(). */
1268 if (ubi_is_module())
1269 goto out_detach;
1270 }
1271
1272 return 0;
1273
1274out_detach:
1275 for (k = 0; k < i; k++)
1276 if (ubi_devices[k]) {
1277 mutex_lock(&ubi_devices_mutex);
1278 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1279 mutex_unlock(&ubi_devices_mutex);
1280 }
1281 ubi_debugfs_exit();
1282out_slab:
1283 kmem_cache_destroy(ubi_wl_entry_slab);
1284out_dev_unreg:
1285 misc_deregister(&ubi_ctrl_cdev);
1286out:
1287 class_unregister(&ubi_class);
1288 pr_err("UBI error: cannot initialize UBI, error %d\n", err);
1289 return err;
1290}
1291late_initcall(ubi_init);
1292
1293static void __exit ubi_exit(void)
1294{
1295 int i;
1296
1297 ubiblock_exit();
1298
1299 for (i = 0; i < UBI_MAX_DEVICES; i++)
1300 if (ubi_devices[i]) {
1301 mutex_lock(&ubi_devices_mutex);
1302 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1303 mutex_unlock(&ubi_devices_mutex);
1304 }
1305 ubi_debugfs_exit();
1306 kmem_cache_destroy(ubi_wl_entry_slab);
1307 misc_deregister(&ubi_ctrl_cdev);
1308 class_unregister(&ubi_class);
1309}
1310module_exit(ubi_exit);
1311
1312/**
1313 * bytes_str_to_int - convert a number of bytes string into an integer.
1314 * @str: the string to convert
1315 *
1316 * This function returns positive resulting integer in case of success and a
1317 * negative error code in case of failure.
1318 */
1319static int bytes_str_to_int(const char *str)
1320{
1321 char *endp;
1322 unsigned long result;
1323
1324 result = simple_strtoul(str, &endp, 0);
1325 if (str == endp || result >= INT_MAX) {
1326 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1327 return -EINVAL;
1328 }
1329
1330 switch (*endp) {
1331 case 'G':
1332 result *= 1024;
1333 case 'M':
1334 result *= 1024;
1335 case 'K':
1336 result *= 1024;
1337 if (endp[1] == 'i' && endp[2] == 'B')
1338 endp += 2;
1339 case '\0':
1340 break;
1341 default:
1342 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1343 return -EINVAL;
1344 }
1345
1346 return result;
1347}
1348
1349/**
1350 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1351 * @val: the parameter value to parse
1352 * @kp: not used
1353 *
1354 * This function returns zero in case of success and a negative error code in
1355 * case of error.
1356 */
1357static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
1358{
1359 int i, len;
1360 struct mtd_dev_param *p;
1361 char buf[MTD_PARAM_LEN_MAX];
1362 char *pbuf = &buf[0];
1363 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1364
1365 if (!val)
1366 return -EINVAL;
1367
1368 if (mtd_devs == UBI_MAX_DEVICES) {
1369 pr_err("UBI error: too many parameters, max. is %d\n",
1370 UBI_MAX_DEVICES);
1371 return -EINVAL;
1372 }
1373
1374 len = strnlen(val, MTD_PARAM_LEN_MAX);
1375 if (len == MTD_PARAM_LEN_MAX) {
1376 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1377 val, MTD_PARAM_LEN_MAX);
1378 return -EINVAL;
1379 }
1380
1381 if (len == 0) {
1382 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1383 return 0;
1384 }
1385
1386 strcpy(buf, val);
1387
1388 /* Get rid of the final newline */
1389 if (buf[len - 1] == '\n')
1390 buf[len - 1] = '\0';
1391
1392 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1393 tokens[i] = strsep(&pbuf, ",");
1394
1395 if (pbuf) {
1396 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1397 return -EINVAL;
1398 }
1399
1400 p = &mtd_dev_param[mtd_devs];
1401 strcpy(&p->name[0], tokens[0]);
1402
1403 token = tokens[1];
1404 if (token) {
1405 p->vid_hdr_offs = bytes_str_to_int(token);
1406
1407 if (p->vid_hdr_offs < 0)
1408 return p->vid_hdr_offs;
1409 }
1410
1411 token = tokens[2];
1412 if (token) {
1413 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1414
1415 if (err) {
1416 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1417 token);
1418 return -EINVAL;
1419 }
1420 }
1421
1422 token = tokens[3];
1423 if (token) {
1424 int err = kstrtoint(token, 10, &p->ubi_num);
1425
1426 if (err) {
1427 pr_err("UBI error: bad value for ubi_num parameter: %s",
1428 token);
1429 return -EINVAL;
1430 }
1431 } else
1432 p->ubi_num = UBI_DEV_NUM_AUTO;
1433
1434 mtd_devs += 1;
1435 return 0;
1436}
1437
1438module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1439MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1440 "Multiple \"mtd\" parameters may be specified.\n"
1441 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1442 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1443 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1444 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1445 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1446 "\n"
1447 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1448 "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"
1449 "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n"
1450 "Example 4: mtd=/dev/mtd1,0,0,5 - attach MTD device /dev/mtd1 to UBI 5 and using default values for the other fields.\n"
1451 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1452#ifdef CONFIG_MTD_UBI_FASTMAP
1453module_param(fm_autoconvert, bool, 0644);
1454MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1455module_param(fm_debug, bool, 0);
1456MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1457#endif
1458MODULE_VERSION(__stringify(UBI_VERSION));
1459MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1460MODULE_AUTHOR("Artem Bityutskiy");
1461MODULE_LICENSE("GPL");