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 */
69 struct 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 */
77 static int mtd_devs;
78
79 /* MTD devices specification parameters */
80 static 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 */
83 static bool fm_autoconvert;
84 static bool fm_debug;
85 #endif
86
87 /* Slab cache for wear-leveling entries */
88 struct kmem_cache *ubi_wl_entry_slab;
89
90 /* UBI control character device */
91 static 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 */
98 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
99
100 /* Serializes UBI devices creations and removals */
101 DEFINE_MUTEX(ubi_devices_mutex);
102
103 /* Protects @ubi_devices and @ubi->ref_count */
104 static DEFINE_SPINLOCK(ubi_devices_lock);
105
106 /* "Show" method for files in '/<sysfs>/class/ubi/' */
107 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
version_show(struct class * class,struct class_attribute * attr,char * buf)108 static ssize_t version_show(struct class *class, struct class_attribute *attr,
109 char *buf)
110 {
111 return sprintf(buf, "%d\n", UBI_VERSION);
112 }
113 static CLASS_ATTR_RO(version);
114
115 static struct attribute *ubi_class_attrs[] = {
116 &class_attr_version.attr,
117 NULL,
118 };
119 ATTRIBUTE_GROUPS(ubi_class);
120
121 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
122 struct class ubi_class = {
123 .name = UBI_NAME_STR,
124 .owner = THIS_MODULE,
125 .class_groups = ubi_class_groups,
126 };
127
128 static 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') */
132 static struct device_attribute dev_eraseblock_size =
133 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
134 static struct device_attribute dev_avail_eraseblocks =
135 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
136 static struct device_attribute dev_total_eraseblocks =
137 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
138 static struct device_attribute dev_volumes_count =
139 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
140 static struct device_attribute dev_max_ec =
141 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
142 static struct device_attribute dev_reserved_for_bad =
143 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
144 static struct device_attribute dev_bad_peb_count =
145 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
146 static struct device_attribute dev_max_vol_count =
147 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
148 static struct device_attribute dev_min_io_size =
149 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
150 static struct device_attribute dev_bgt_enabled =
151 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
152 static struct device_attribute dev_mtd_num =
153 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
154 static 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 */
ubi_volume_notify(struct ubi_device * ubi,struct ubi_volume * vol,int ntype)167 int 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 */
ubi_notify_all(struct ubi_device * ubi,int ntype,struct notifier_block * nb)199 int 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 */
ubi_enumerate_volumes(struct notifier_block * nb)238 int 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 */
ubi_get_device(int ubi_num)266 struct 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 */
ubi_put_device(struct ubi_device * ubi)286 void 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 */
ubi_get_by_major(int major)301 struct 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 */
ubi_major2num(int major)330 int 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/' */
dev_attribute_show(struct device * dev,struct device_attribute * attr,char * buf)349 static 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
401 static 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 };
416 ATTRIBUTE_GROUPS(ubi_dev);
417
dev_release(struct device * dev)418 static 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 */
kill_volumes(struct ubi_device * ubi)429 static 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 */
uif_init(struct ubi_device * ubi)449 static 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
493 out_volumes:
494 kill_volumes(ubi);
495 cdev_device_del(&ubi->cdev, &ubi->dev);
496 out_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 */
uif_close(struct ubi_device * ubi)511 static 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 */
ubi_free_internal_volumes(struct ubi_device * ubi)522 void 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 ubi_fastmap_destroy_checkmap(ubi->volumes[i]);
530 kfree(ubi->volumes[i]);
531 }
532 }
533
get_bad_peb_limit(const struct ubi_device * ubi,int max_beb_per1024)534 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
535 {
536 int limit, device_pebs;
537 uint64_t device_size;
538
539 if (!max_beb_per1024)
540 return 0;
541
542 /*
543 * Here we are using size of the entire flash chip and
544 * not just the MTD partition size because the maximum
545 * number of bad eraseblocks is a percentage of the
546 * whole device and bad eraseblocks are not fairly
547 * distributed over the flash chip. So the worst case
548 * is that all the bad eraseblocks of the chip are in
549 * the MTD partition we are attaching (ubi->mtd).
550 */
551 device_size = mtd_get_device_size(ubi->mtd);
552 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
553 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
554
555 /* Round it up */
556 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
557 limit += 1;
558
559 return limit;
560 }
561
562 /**
563 * io_init - initialize I/O sub-system for a given UBI device.
564 * @ubi: UBI device description object
565 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
566 *
567 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
568 * assumed:
569 * o EC header is always at offset zero - this cannot be changed;
570 * o VID header starts just after the EC header at the closest address
571 * aligned to @io->hdrs_min_io_size;
572 * o data starts just after the VID header at the closest address aligned to
573 * @io->min_io_size
574 *
575 * This function returns zero in case of success and a negative error code in
576 * case of failure.
577 */
io_init(struct ubi_device * ubi,int max_beb_per1024)578 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
579 {
580 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
581 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
582
583 if (ubi->mtd->numeraseregions != 0) {
584 /*
585 * Some flashes have several erase regions. Different regions
586 * may have different eraseblock size and other
587 * characteristics. It looks like mostly multi-region flashes
588 * have one "main" region and one or more small regions to
589 * store boot loader code or boot parameters or whatever. I
590 * guess we should just pick the largest region. But this is
591 * not implemented.
592 */
593 ubi_err(ubi, "multiple regions, not implemented");
594 return -EINVAL;
595 }
596
597 if (ubi->vid_hdr_offset < 0)
598 return -EINVAL;
599
600 /*
601 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
602 * physical eraseblocks maximum.
603 */
604
605 ubi->peb_size = ubi->mtd->erasesize;
606 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
607 ubi->flash_size = ubi->mtd->size;
608
609 if (mtd_can_have_bb(ubi->mtd)) {
610 ubi->bad_allowed = 1;
611 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
612 }
613
614 if (ubi->mtd->type == MTD_NORFLASH) {
615 ubi_assert(ubi->mtd->writesize == 1);
616 ubi->nor_flash = 1;
617 }
618
619 ubi->min_io_size = ubi->mtd->writesize;
620 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
621
622 /*
623 * Make sure minimal I/O unit is power of 2. Note, there is no
624 * fundamental reason for this assumption. It is just an optimization
625 * which allows us to avoid costly division operations.
626 */
627 if (!is_power_of_2(ubi->min_io_size)) {
628 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
629 ubi->min_io_size);
630 return -EINVAL;
631 }
632
633 ubi_assert(ubi->hdrs_min_io_size > 0);
634 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
635 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
636
637 ubi->max_write_size = ubi->mtd->writebufsize;
638 /*
639 * Maximum write size has to be greater or equivalent to min. I/O
640 * size, and be multiple of min. I/O size.
641 */
642 if (ubi->max_write_size < ubi->min_io_size ||
643 ubi->max_write_size % ubi->min_io_size ||
644 !is_power_of_2(ubi->max_write_size)) {
645 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
646 ubi->max_write_size, ubi->min_io_size);
647 return -EINVAL;
648 }
649
650 /* Calculate default aligned sizes of EC and VID headers */
651 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
652 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
653
654 dbg_gen("min_io_size %d", ubi->min_io_size);
655 dbg_gen("max_write_size %d", ubi->max_write_size);
656 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
657 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
658 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
659
660 if (ubi->vid_hdr_offset == 0)
661 /* Default offset */
662 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
663 ubi->ec_hdr_alsize;
664 else {
665 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
666 ~(ubi->hdrs_min_io_size - 1);
667 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
668 ubi->vid_hdr_aloffset;
669 }
670
671 /* Similar for the data offset */
672 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
673 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
674
675 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
676 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
677 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
678 dbg_gen("leb_start %d", ubi->leb_start);
679
680 /* The shift must be aligned to 32-bit boundary */
681 if (ubi->vid_hdr_shift % 4) {
682 ubi_err(ubi, "unaligned VID header shift %d",
683 ubi->vid_hdr_shift);
684 return -EINVAL;
685 }
686
687 /* Check sanity */
688 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
689 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
690 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
691 ubi->leb_start & (ubi->min_io_size - 1)) {
692 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
693 ubi->vid_hdr_offset, ubi->leb_start);
694 return -EINVAL;
695 }
696
697 /*
698 * Set maximum amount of physical erroneous eraseblocks to be 10%.
699 * Erroneous PEB are those which have read errors.
700 */
701 ubi->max_erroneous = ubi->peb_count / 10;
702 if (ubi->max_erroneous < 16)
703 ubi->max_erroneous = 16;
704 dbg_gen("max_erroneous %d", ubi->max_erroneous);
705
706 /*
707 * It may happen that EC and VID headers are situated in one minimal
708 * I/O unit. In this case we can only accept this UBI image in
709 * read-only mode.
710 */
711 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
712 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
713 ubi->ro_mode = 1;
714 }
715
716 ubi->leb_size = ubi->peb_size - ubi->leb_start;
717
718 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
719 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
720 ubi->mtd->index);
721 ubi->ro_mode = 1;
722 }
723
724 /*
725 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
726 * unfortunately, MTD does not provide this information. We should loop
727 * over all physical eraseblocks and invoke mtd->block_is_bad() for
728 * each physical eraseblock. So, we leave @ubi->bad_peb_count
729 * uninitialized so far.
730 */
731
732 return 0;
733 }
734
735 /**
736 * autoresize - re-size the volume which has the "auto-resize" flag set.
737 * @ubi: UBI device description object
738 * @vol_id: ID of the volume to re-size
739 *
740 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
741 * the volume table to the largest possible size. See comments in ubi-header.h
742 * for more description of the flag. Returns zero in case of success and a
743 * negative error code in case of failure.
744 */
autoresize(struct ubi_device * ubi,int vol_id)745 static int autoresize(struct ubi_device *ubi, int vol_id)
746 {
747 struct ubi_volume_desc desc;
748 struct ubi_volume *vol = ubi->volumes[vol_id];
749 int err, old_reserved_pebs = vol->reserved_pebs;
750
751 if (ubi->ro_mode) {
752 ubi_warn(ubi, "skip auto-resize because of R/O mode");
753 return 0;
754 }
755
756 /*
757 * Clear the auto-resize flag in the volume in-memory copy of the
758 * volume table, and 'ubi_resize_volume()' will propagate this change
759 * to the flash.
760 */
761 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
762
763 if (ubi->avail_pebs == 0) {
764 struct ubi_vtbl_record vtbl_rec;
765
766 /*
767 * No available PEBs to re-size the volume, clear the flag on
768 * flash and exit.
769 */
770 vtbl_rec = ubi->vtbl[vol_id];
771 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
772 if (err)
773 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
774 vol_id);
775 } else {
776 desc.vol = vol;
777 err = ubi_resize_volume(&desc,
778 old_reserved_pebs + ubi->avail_pebs);
779 if (err)
780 ubi_err(ubi, "cannot auto-resize volume %d",
781 vol_id);
782 }
783
784 if (err)
785 return err;
786
787 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
788 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
789 return 0;
790 }
791
792 /**
793 * ubi_attach_mtd_dev - attach an MTD device.
794 * @mtd: MTD device description object
795 * @ubi_num: number to assign to the new UBI device
796 * @vid_hdr_offset: VID header offset
797 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
798 *
799 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
800 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
801 * which case this function finds a vacant device number and assigns it
802 * automatically. Returns the new UBI device number in case of success and a
803 * negative error code in case of failure.
804 *
805 * Note, the invocations of this function has to be serialized by the
806 * @ubi_devices_mutex.
807 */
ubi_attach_mtd_dev(struct mtd_info * mtd,int ubi_num,int vid_hdr_offset,int max_beb_per1024)808 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
809 int vid_hdr_offset, int max_beb_per1024)
810 {
811 struct ubi_device *ubi;
812 int i, err;
813
814 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
815 return -EINVAL;
816
817 if (!max_beb_per1024)
818 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
819
820 /*
821 * Check if we already have the same MTD device attached.
822 *
823 * Note, this function assumes that UBI devices creations and deletions
824 * are serialized, so it does not take the &ubi_devices_lock.
825 */
826 for (i = 0; i < UBI_MAX_DEVICES; i++) {
827 ubi = ubi_devices[i];
828 if (ubi && mtd->index == ubi->mtd->index) {
829 pr_err("ubi: mtd%d is already attached to ubi%d\n",
830 mtd->index, i);
831 return -EEXIST;
832 }
833 }
834
835 /*
836 * Make sure this MTD device is not emulated on top of an UBI volume
837 * already. Well, generally this recursion works fine, but there are
838 * different problems like the UBI module takes a reference to itself
839 * by attaching (and thus, opening) the emulated MTD device. This
840 * results in inability to unload the module. And in general it makes
841 * no sense to attach emulated MTD devices, so we prohibit this.
842 */
843 if (mtd->type == MTD_UBIVOLUME) {
844 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",
845 mtd->index);
846 return -EINVAL;
847 }
848
849 /*
850 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
851 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
852 * will die soon and you will lose all your data.
853 */
854 if (mtd->type == MTD_MLCNANDFLASH) {
855 pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
856 mtd->index);
857 return -EINVAL;
858 }
859
860 if (ubi_num == UBI_DEV_NUM_AUTO) {
861 /* Search for an empty slot in the @ubi_devices array */
862 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
863 if (!ubi_devices[ubi_num])
864 break;
865 if (ubi_num == UBI_MAX_DEVICES) {
866 pr_err("ubi: only %d UBI devices may be created\n",
867 UBI_MAX_DEVICES);
868 return -ENFILE;
869 }
870 } else {
871 if (ubi_num >= UBI_MAX_DEVICES)
872 return -EINVAL;
873
874 /* Make sure ubi_num is not busy */
875 if (ubi_devices[ubi_num]) {
876 pr_err("ubi: ubi%i already exists\n", ubi_num);
877 return -EEXIST;
878 }
879 }
880
881 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
882 if (!ubi)
883 return -ENOMEM;
884
885 device_initialize(&ubi->dev);
886 ubi->dev.release = dev_release;
887 ubi->dev.class = &ubi_class;
888 ubi->dev.groups = ubi_dev_groups;
889
890 ubi->mtd = mtd;
891 ubi->ubi_num = ubi_num;
892 ubi->vid_hdr_offset = vid_hdr_offset;
893 ubi->autoresize_vol_id = -1;
894
895 #ifdef CONFIG_MTD_UBI_FASTMAP
896 ubi->fm_pool.used = ubi->fm_pool.size = 0;
897 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
898
899 /*
900 * fm_pool.max_size is 5% of the total number of PEBs but it's also
901 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
902 */
903 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
904 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
905 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
906 UBI_FM_MIN_POOL_SIZE);
907
908 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
909 ubi->fm_disabled = !fm_autoconvert;
910 if (fm_debug)
911 ubi_enable_dbg_chk_fastmap(ubi);
912
913 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
914 <= UBI_FM_MAX_START) {
915 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
916 UBI_FM_MAX_START);
917 ubi->fm_disabled = 1;
918 }
919
920 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
921 ubi_msg(ubi, "default fastmap WL pool size: %d",
922 ubi->fm_wl_pool.max_size);
923 #else
924 ubi->fm_disabled = 1;
925 #endif
926 mutex_init(&ubi->buf_mutex);
927 mutex_init(&ubi->ckvol_mutex);
928 mutex_init(&ubi->device_mutex);
929 spin_lock_init(&ubi->volumes_lock);
930 init_rwsem(&ubi->fm_protect);
931 init_rwsem(&ubi->fm_eba_sem);
932
933 ubi_msg(ubi, "attaching mtd%d", mtd->index);
934
935 err = io_init(ubi, max_beb_per1024);
936 if (err)
937 goto out_free;
938
939 err = -ENOMEM;
940 ubi->peb_buf = vmalloc(ubi->peb_size);
941 if (!ubi->peb_buf)
942 goto out_free;
943
944 #ifdef CONFIG_MTD_UBI_FASTMAP
945 ubi->fm_size = ubi_calc_fm_size(ubi);
946 ubi->fm_buf = vzalloc(ubi->fm_size);
947 if (!ubi->fm_buf)
948 goto out_free;
949 #endif
950 err = ubi_attach(ubi, 0);
951 if (err) {
952 ubi_err(ubi, "failed to attach mtd%d, error %d",
953 mtd->index, err);
954 goto out_free;
955 }
956
957 if (ubi->autoresize_vol_id != -1) {
958 err = autoresize(ubi, ubi->autoresize_vol_id);
959 if (err)
960 goto out_detach;
961 }
962
963 /* Make device "available" before it becomes accessible via sysfs */
964 ubi_devices[ubi_num] = ubi;
965
966 err = uif_init(ubi);
967 if (err)
968 goto out_detach;
969
970 err = ubi_debugfs_init_dev(ubi);
971 if (err)
972 goto out_uif;
973
974 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
975 if (IS_ERR(ubi->bgt_thread)) {
976 err = PTR_ERR(ubi->bgt_thread);
977 ubi_err(ubi, "cannot spawn \"%s\", error %d",
978 ubi->bgt_name, err);
979 goto out_debugfs;
980 }
981
982 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
983 mtd->index, mtd->name, ubi->flash_size >> 20);
984 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
985 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
986 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
987 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
988 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
989 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
990 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
991 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
992 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
993 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
994 ubi->vtbl_slots);
995 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
996 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
997 ubi->image_seq);
998 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
999 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1000
1001 /*
1002 * The below lock makes sure we do not race with 'ubi_thread()' which
1003 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1004 */
1005 spin_lock(&ubi->wl_lock);
1006 ubi->thread_enabled = 1;
1007 wake_up_process(ubi->bgt_thread);
1008 spin_unlock(&ubi->wl_lock);
1009
1010 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1011 return ubi_num;
1012
1013 out_debugfs:
1014 ubi_debugfs_exit_dev(ubi);
1015 out_uif:
1016 uif_close(ubi);
1017 out_detach:
1018 ubi_devices[ubi_num] = NULL;
1019 ubi_wl_close(ubi);
1020 ubi_free_internal_volumes(ubi);
1021 vfree(ubi->vtbl);
1022 out_free:
1023 vfree(ubi->peb_buf);
1024 vfree(ubi->fm_buf);
1025 put_device(&ubi->dev);
1026 return err;
1027 }
1028
1029 /**
1030 * ubi_detach_mtd_dev - detach an MTD device.
1031 * @ubi_num: UBI device number to detach from
1032 * @anyway: detach MTD even if device reference count is not zero
1033 *
1034 * This function destroys an UBI device number @ubi_num and detaches the
1035 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1036 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1037 * exist.
1038 *
1039 * Note, the invocations of this function has to be serialized by the
1040 * @ubi_devices_mutex.
1041 */
ubi_detach_mtd_dev(int ubi_num,int anyway)1042 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1043 {
1044 struct ubi_device *ubi;
1045
1046 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1047 return -EINVAL;
1048
1049 ubi = ubi_get_device(ubi_num);
1050 if (!ubi)
1051 return -EINVAL;
1052
1053 spin_lock(&ubi_devices_lock);
1054 put_device(&ubi->dev);
1055 ubi->ref_count -= 1;
1056 if (ubi->ref_count) {
1057 if (!anyway) {
1058 spin_unlock(&ubi_devices_lock);
1059 return -EBUSY;
1060 }
1061 /* This may only happen if there is a bug */
1062 ubi_err(ubi, "%s reference count %d, destroy anyway",
1063 ubi->ubi_name, ubi->ref_count);
1064 }
1065 ubi_devices[ubi_num] = NULL;
1066 spin_unlock(&ubi_devices_lock);
1067
1068 ubi_assert(ubi_num == ubi->ubi_num);
1069 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1070 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1071 #ifdef CONFIG_MTD_UBI_FASTMAP
1072 /* If we don't write a new fastmap at detach time we lose all
1073 * EC updates that have been made since the last written fastmap.
1074 * In case of fastmap debugging we omit the update to simulate an
1075 * unclean shutdown. */
1076 if (!ubi_dbg_chk_fastmap(ubi))
1077 ubi_update_fastmap(ubi);
1078 #endif
1079 /*
1080 * Before freeing anything, we have to stop the background thread to
1081 * prevent it from doing anything on this device while we are freeing.
1082 */
1083 if (ubi->bgt_thread)
1084 kthread_stop(ubi->bgt_thread);
1085
1086 #ifdef CONFIG_MTD_UBI_FASTMAP
1087 cancel_work_sync(&ubi->fm_work);
1088 #endif
1089 ubi_debugfs_exit_dev(ubi);
1090 uif_close(ubi);
1091
1092 ubi_wl_close(ubi);
1093 ubi_free_internal_volumes(ubi);
1094 vfree(ubi->vtbl);
1095 vfree(ubi->peb_buf);
1096 vfree(ubi->fm_buf);
1097 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1098 put_mtd_device(ubi->mtd);
1099 put_device(&ubi->dev);
1100 return 0;
1101 }
1102
1103 /**
1104 * open_mtd_by_chdev - open an MTD device by its character device node path.
1105 * @mtd_dev: MTD character device node path
1106 *
1107 * This helper function opens an MTD device by its character node device path.
1108 * Returns MTD device description object in case of success and a negative
1109 * error code in case of failure.
1110 */
open_mtd_by_chdev(const char * mtd_dev)1111 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1112 {
1113 int err, minor;
1114 struct path path;
1115 struct kstat stat;
1116
1117 /* Probably this is an MTD character device node path */
1118 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1119 if (err)
1120 return ERR_PTR(err);
1121
1122 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1123 path_put(&path);
1124 if (err)
1125 return ERR_PTR(err);
1126
1127 /* MTD device number is defined by the major / minor numbers */
1128 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1129 return ERR_PTR(-EINVAL);
1130
1131 minor = MINOR(stat.rdev);
1132
1133 if (minor & 1)
1134 /*
1135 * Just do not think the "/dev/mtdrX" devices support is need,
1136 * so do not support them to avoid doing extra work.
1137 */
1138 return ERR_PTR(-EINVAL);
1139
1140 return get_mtd_device(NULL, minor / 2);
1141 }
1142
1143 /**
1144 * open_mtd_device - open MTD device by name, character device path, or number.
1145 * @mtd_dev: name, character device node path, or MTD device device number
1146 *
1147 * This function tries to open and MTD device described by @mtd_dev string,
1148 * which is first treated as ASCII MTD device number, and if it is not true, it
1149 * is treated as MTD device name, and if that is also not true, it is treated
1150 * as MTD character device node path. Returns MTD device description object in
1151 * case of success and a negative error code in case of failure.
1152 */
open_mtd_device(const char * mtd_dev)1153 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1154 {
1155 struct mtd_info *mtd;
1156 int mtd_num;
1157 char *endp;
1158
1159 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1160 if (*endp != '\0' || mtd_dev == endp) {
1161 /*
1162 * This does not look like an ASCII integer, probably this is
1163 * MTD device name.
1164 */
1165 mtd = get_mtd_device_nm(mtd_dev);
1166 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1167 /* Probably this is an MTD character device node path */
1168 mtd = open_mtd_by_chdev(mtd_dev);
1169 } else
1170 mtd = get_mtd_device(NULL, mtd_num);
1171
1172 return mtd;
1173 }
1174
ubi_init(void)1175 static int __init ubi_init(void)
1176 {
1177 int err, i, k;
1178
1179 /* Ensure that EC and VID headers have correct size */
1180 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1181 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1182
1183 if (mtd_devs > UBI_MAX_DEVICES) {
1184 pr_err("UBI error: too many MTD devices, maximum is %d\n",
1185 UBI_MAX_DEVICES);
1186 return -EINVAL;
1187 }
1188
1189 /* Create base sysfs directory and sysfs files */
1190 err = class_register(&ubi_class);
1191 if (err < 0)
1192 return err;
1193
1194 err = misc_register(&ubi_ctrl_cdev);
1195 if (err) {
1196 pr_err("UBI error: cannot register device\n");
1197 goto out;
1198 }
1199
1200 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1201 sizeof(struct ubi_wl_entry),
1202 0, 0, NULL);
1203 if (!ubi_wl_entry_slab) {
1204 err = -ENOMEM;
1205 goto out_dev_unreg;
1206 }
1207
1208 err = ubi_debugfs_init();
1209 if (err)
1210 goto out_slab;
1211
1212
1213 /* Attach MTD devices */
1214 for (i = 0; i < mtd_devs; i++) {
1215 struct mtd_dev_param *p = &mtd_dev_param[i];
1216 struct mtd_info *mtd;
1217
1218 cond_resched();
1219
1220 mtd = open_mtd_device(p->name);
1221 if (IS_ERR(mtd)) {
1222 err = PTR_ERR(mtd);
1223 pr_err("UBI error: cannot open mtd %s, error %d\n",
1224 p->name, err);
1225 /* See comment below re-ubi_is_module(). */
1226 if (ubi_is_module())
1227 goto out_detach;
1228 continue;
1229 }
1230
1231 mutex_lock(&ubi_devices_mutex);
1232 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1233 p->vid_hdr_offs, p->max_beb_per1024);
1234 mutex_unlock(&ubi_devices_mutex);
1235 if (err < 0) {
1236 pr_err("UBI error: cannot attach mtd%d\n",
1237 mtd->index);
1238 put_mtd_device(mtd);
1239
1240 /*
1241 * Originally UBI stopped initializing on any error.
1242 * However, later on it was found out that this
1243 * behavior is not very good when UBI is compiled into
1244 * the kernel and the MTD devices to attach are passed
1245 * through the command line. Indeed, UBI failure
1246 * stopped whole boot sequence.
1247 *
1248 * To fix this, we changed the behavior for the
1249 * non-module case, but preserved the old behavior for
1250 * the module case, just for compatibility. This is a
1251 * little inconsistent, though.
1252 */
1253 if (ubi_is_module())
1254 goto out_detach;
1255 }
1256 }
1257
1258 err = ubiblock_init();
1259 if (err) {
1260 pr_err("UBI error: block: cannot initialize, error %d\n", err);
1261
1262 /* See comment above re-ubi_is_module(). */
1263 if (ubi_is_module())
1264 goto out_detach;
1265 }
1266
1267 return 0;
1268
1269 out_detach:
1270 for (k = 0; k < i; k++)
1271 if (ubi_devices[k]) {
1272 mutex_lock(&ubi_devices_mutex);
1273 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1274 mutex_unlock(&ubi_devices_mutex);
1275 }
1276 ubi_debugfs_exit();
1277 out_slab:
1278 kmem_cache_destroy(ubi_wl_entry_slab);
1279 out_dev_unreg:
1280 misc_deregister(&ubi_ctrl_cdev);
1281 out:
1282 class_unregister(&ubi_class);
1283 pr_err("UBI error: cannot initialize UBI, error %d\n", err);
1284 return err;
1285 }
1286 late_initcall(ubi_init);
1287
ubi_exit(void)1288 static void __exit ubi_exit(void)
1289 {
1290 int i;
1291
1292 ubiblock_exit();
1293
1294 for (i = 0; i < UBI_MAX_DEVICES; i++)
1295 if (ubi_devices[i]) {
1296 mutex_lock(&ubi_devices_mutex);
1297 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1298 mutex_unlock(&ubi_devices_mutex);
1299 }
1300 ubi_debugfs_exit();
1301 kmem_cache_destroy(ubi_wl_entry_slab);
1302 misc_deregister(&ubi_ctrl_cdev);
1303 class_unregister(&ubi_class);
1304 }
1305 module_exit(ubi_exit);
1306
1307 /**
1308 * bytes_str_to_int - convert a number of bytes string into an integer.
1309 * @str: the string to convert
1310 *
1311 * This function returns positive resulting integer in case of success and a
1312 * negative error code in case of failure.
1313 */
bytes_str_to_int(const char * str)1314 static int bytes_str_to_int(const char *str)
1315 {
1316 char *endp;
1317 unsigned long result;
1318
1319 result = simple_strtoul(str, &endp, 0);
1320 if (str == endp || result >= INT_MAX) {
1321 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1322 return -EINVAL;
1323 }
1324
1325 switch (*endp) {
1326 case 'G':
1327 result *= 1024;
1328 case 'M':
1329 result *= 1024;
1330 case 'K':
1331 result *= 1024;
1332 if (endp[1] == 'i' && endp[2] == 'B')
1333 endp += 2;
1334 case '\0':
1335 break;
1336 default:
1337 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1338 return -EINVAL;
1339 }
1340
1341 return result;
1342 }
1343
1344 /**
1345 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1346 * @val: the parameter value to parse
1347 * @kp: not used
1348 *
1349 * This function returns zero in case of success and a negative error code in
1350 * case of error.
1351 */
ubi_mtd_param_parse(const char * val,const struct kernel_param * kp)1352 static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
1353 {
1354 int i, len;
1355 struct mtd_dev_param *p;
1356 char buf[MTD_PARAM_LEN_MAX];
1357 char *pbuf = &buf[0];
1358 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1359
1360 if (!val)
1361 return -EINVAL;
1362
1363 if (mtd_devs == UBI_MAX_DEVICES) {
1364 pr_err("UBI error: too many parameters, max. is %d\n",
1365 UBI_MAX_DEVICES);
1366 return -EINVAL;
1367 }
1368
1369 len = strnlen(val, MTD_PARAM_LEN_MAX);
1370 if (len == MTD_PARAM_LEN_MAX) {
1371 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1372 val, MTD_PARAM_LEN_MAX);
1373 return -EINVAL;
1374 }
1375
1376 if (len == 0) {
1377 pr_warn("UBI warning: empty 'mtd=' parameter - 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 < MTD_PARAM_MAX_COUNT; i++)
1388 tokens[i] = strsep(&pbuf, ",");
1389
1390 if (pbuf) {
1391 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1392 return -EINVAL;
1393 }
1394
1395 p = &mtd_dev_param[mtd_devs];
1396 strcpy(&p->name[0], tokens[0]);
1397
1398 token = tokens[1];
1399 if (token) {
1400 p->vid_hdr_offs = bytes_str_to_int(token);
1401
1402 if (p->vid_hdr_offs < 0)
1403 return p->vid_hdr_offs;
1404 }
1405
1406 token = tokens[2];
1407 if (token) {
1408 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1409
1410 if (err) {
1411 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1412 token);
1413 return -EINVAL;
1414 }
1415 }
1416
1417 token = tokens[3];
1418 if (token) {
1419 int err = kstrtoint(token, 10, &p->ubi_num);
1420
1421 if (err) {
1422 pr_err("UBI error: bad value for ubi_num parameter: %s",
1423 token);
1424 return -EINVAL;
1425 }
1426 } else
1427 p->ubi_num = UBI_DEV_NUM_AUTO;
1428
1429 mtd_devs += 1;
1430 return 0;
1431 }
1432
1433 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1434 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1435 "Multiple \"mtd\" parameters may be specified.\n"
1436 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1437 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1438 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1439 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1440 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1441 "\n"
1442 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1443 "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"
1444 "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"
1445 "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"
1446 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1447 #ifdef CONFIG_MTD_UBI_FASTMAP
1448 module_param(fm_autoconvert, bool, 0644);
1449 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1450 module_param(fm_debug, bool, 0);
1451 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1452 #endif
1453 MODULE_VERSION(__stringify(UBI_VERSION));
1454 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1455 MODULE_AUTHOR("Artem Bityutskiy");
1456 MODULE_LICENSE("GPL");
1457