1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2006
4 * Copyright (c) Nokia Corporation, 2007
5 *
6 * Author: Artem Bityutskiy (Битюцкий Артём),
7 * Frank Haverkamp
8 */
9
10 /*
11 * This file includes UBI initialization and building of UBI devices.
12 *
13 * When UBI is initialized, it attaches all the MTD devices specified as the
14 * module load parameters or the kernel boot parameters. If MTD devices were
15 * specified, UBI does not attach any MTD device, but it is possible to do
16 * later using the "UBI control device".
17 */
18
19 #include <linux/err.h>
20 #include <linux/module.h>
21 #include <linux/moduleparam.h>
22 #include <linux/stringify.h>
23 #include <linux/namei.h>
24 #include <linux/stat.h>
25 #include <linux/miscdevice.h>
26 #include <linux/mtd/partitions.h>
27 #include <linux/log2.h>
28 #include <linux/kthread.h>
29 #include <linux/kernel.h>
30 #include <linux/slab.h>
31 #include <linux/major.h>
32 #include "ubi.h"
33
34 /* Maximum length of the 'mtd=' parameter */
35 #define MTD_PARAM_LEN_MAX 64
36
37 /* Maximum number of comma-separated items in the 'mtd=' parameter */
38 #define MTD_PARAM_MAX_COUNT 4
39
40 /* Maximum value for the number of bad PEBs per 1024 PEBs */
41 #define MAX_MTD_UBI_BEB_LIMIT 768
42
43 #ifdef CONFIG_MTD_UBI_MODULE
44 #define ubi_is_module() 1
45 #else
46 #define ubi_is_module() 0
47 #endif
48
49 /**
50 * struct mtd_dev_param - MTD device parameter description data structure.
51 * @name: MTD character device node path, MTD device name, or MTD device number
52 * string
53 * @vid_hdr_offs: VID header offset
54 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
55 */
56 struct mtd_dev_param {
57 char name[MTD_PARAM_LEN_MAX];
58 int ubi_num;
59 int vid_hdr_offs;
60 int max_beb_per1024;
61 };
62
63 /* Numbers of elements set in the @mtd_dev_param array */
64 static int mtd_devs;
65
66 /* MTD devices specification parameters */
67 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
68 #ifdef CONFIG_MTD_UBI_FASTMAP
69 /* UBI module parameter to enable fastmap automatically on non-fastmap images */
70 static bool fm_autoconvert;
71 static bool fm_debug;
72 #endif
73
74 /* Slab cache for wear-leveling entries */
75 struct kmem_cache *ubi_wl_entry_slab;
76
77 /* UBI control character device */
78 static struct miscdevice ubi_ctrl_cdev = {
79 .minor = MISC_DYNAMIC_MINOR,
80 .name = "ubi_ctrl",
81 .fops = &ubi_ctrl_cdev_operations,
82 };
83
84 /* All UBI devices in system */
85 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
86
87 /* Serializes UBI devices creations and removals */
88 DEFINE_MUTEX(ubi_devices_mutex);
89
90 /* Protects @ubi_devices and @ubi->ref_count */
91 static DEFINE_SPINLOCK(ubi_devices_lock);
92
93 /* "Show" method for files in '/<sysfs>/class/ubi/' */
94 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
version_show(struct class * class,struct class_attribute * attr,char * buf)95 static ssize_t version_show(struct class *class, struct class_attribute *attr,
96 char *buf)
97 {
98 return sprintf(buf, "%d\n", UBI_VERSION);
99 }
100 static CLASS_ATTR_RO(version);
101
102 static struct attribute *ubi_class_attrs[] = {
103 &class_attr_version.attr,
104 NULL,
105 };
106 ATTRIBUTE_GROUPS(ubi_class);
107
108 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
109 struct class ubi_class = {
110 .name = UBI_NAME_STR,
111 .owner = THIS_MODULE,
112 .class_groups = ubi_class_groups,
113 };
114
115 static ssize_t dev_attribute_show(struct device *dev,
116 struct device_attribute *attr, char *buf);
117
118 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
119 static struct device_attribute dev_eraseblock_size =
120 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
121 static struct device_attribute dev_avail_eraseblocks =
122 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
123 static struct device_attribute dev_total_eraseblocks =
124 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
125 static struct device_attribute dev_volumes_count =
126 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
127 static struct device_attribute dev_max_ec =
128 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
129 static struct device_attribute dev_reserved_for_bad =
130 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
131 static struct device_attribute dev_bad_peb_count =
132 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
133 static struct device_attribute dev_max_vol_count =
134 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
135 static struct device_attribute dev_min_io_size =
136 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
137 static struct device_attribute dev_bgt_enabled =
138 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
139 static struct device_attribute dev_mtd_num =
140 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
141 static struct device_attribute dev_ro_mode =
142 __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
143
144 /**
145 * ubi_volume_notify - send a volume change notification.
146 * @ubi: UBI device description object
147 * @vol: volume description object of the changed volume
148 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
149 *
150 * This is a helper function which notifies all subscribers about a volume
151 * change event (creation, removal, re-sizing, re-naming, updating). Returns
152 * zero in case of success and a negative error code in case of failure.
153 */
ubi_volume_notify(struct ubi_device * ubi,struct ubi_volume * vol,int ntype)154 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
155 {
156 int ret;
157 struct ubi_notification nt;
158
159 ubi_do_get_device_info(ubi, &nt.di);
160 ubi_do_get_volume_info(ubi, vol, &nt.vi);
161
162 switch (ntype) {
163 case UBI_VOLUME_ADDED:
164 case UBI_VOLUME_REMOVED:
165 case UBI_VOLUME_RESIZED:
166 case UBI_VOLUME_RENAMED:
167 ret = ubi_update_fastmap(ubi);
168 if (ret)
169 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
170 }
171
172 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
173 }
174
175 /**
176 * ubi_notify_all - send a notification to all volumes.
177 * @ubi: UBI device description object
178 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
179 * @nb: the notifier to call
180 *
181 * This function walks all volumes of UBI device @ubi and sends the @ntype
182 * notification for each volume. If @nb is %NULL, then all registered notifiers
183 * are called, otherwise only the @nb notifier is called. Returns the number of
184 * sent notifications.
185 */
ubi_notify_all(struct ubi_device * ubi,int ntype,struct notifier_block * nb)186 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
187 {
188 struct ubi_notification nt;
189 int i, count = 0;
190
191 ubi_do_get_device_info(ubi, &nt.di);
192
193 mutex_lock(&ubi->device_mutex);
194 for (i = 0; i < ubi->vtbl_slots; i++) {
195 /*
196 * Since the @ubi->device is locked, and we are not going to
197 * change @ubi->volumes, we do not have to lock
198 * @ubi->volumes_lock.
199 */
200 if (!ubi->volumes[i])
201 continue;
202
203 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
204 if (nb)
205 nb->notifier_call(nb, ntype, &nt);
206 else
207 blocking_notifier_call_chain(&ubi_notifiers, ntype,
208 &nt);
209 count += 1;
210 }
211 mutex_unlock(&ubi->device_mutex);
212
213 return count;
214 }
215
216 /**
217 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
218 * @nb: the notifier to call
219 *
220 * This function walks all UBI devices and volumes and sends the
221 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
222 * registered notifiers are called, otherwise only the @nb notifier is called.
223 * Returns the number of sent notifications.
224 */
ubi_enumerate_volumes(struct notifier_block * nb)225 int ubi_enumerate_volumes(struct notifier_block *nb)
226 {
227 int i, count = 0;
228
229 /*
230 * Since the @ubi_devices_mutex is locked, and we are not going to
231 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
232 */
233 for (i = 0; i < UBI_MAX_DEVICES; i++) {
234 struct ubi_device *ubi = ubi_devices[i];
235
236 if (!ubi)
237 continue;
238 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
239 }
240
241 return count;
242 }
243
244 /**
245 * ubi_get_device - get UBI device.
246 * @ubi_num: UBI device number
247 *
248 * This function returns UBI device description object for UBI device number
249 * @ubi_num, or %NULL if the device does not exist. This function increases the
250 * device reference count to prevent removal of the device. In other words, the
251 * device cannot be removed if its reference count is not zero.
252 */
ubi_get_device(int ubi_num)253 struct ubi_device *ubi_get_device(int ubi_num)
254 {
255 struct ubi_device *ubi;
256
257 spin_lock(&ubi_devices_lock);
258 ubi = ubi_devices[ubi_num];
259 if (ubi) {
260 ubi_assert(ubi->ref_count >= 0);
261 ubi->ref_count += 1;
262 get_device(&ubi->dev);
263 }
264 spin_unlock(&ubi_devices_lock);
265
266 return ubi;
267 }
268
269 /**
270 * ubi_put_device - drop an UBI device reference.
271 * @ubi: UBI device description object
272 */
ubi_put_device(struct ubi_device * ubi)273 void ubi_put_device(struct ubi_device *ubi)
274 {
275 spin_lock(&ubi_devices_lock);
276 ubi->ref_count -= 1;
277 put_device(&ubi->dev);
278 spin_unlock(&ubi_devices_lock);
279 }
280
281 /**
282 * ubi_get_by_major - get UBI device by character device major number.
283 * @major: major number
284 *
285 * This function is similar to 'ubi_get_device()', but it searches the device
286 * by its major number.
287 */
ubi_get_by_major(int major)288 struct ubi_device *ubi_get_by_major(int major)
289 {
290 int i;
291 struct ubi_device *ubi;
292
293 spin_lock(&ubi_devices_lock);
294 for (i = 0; i < UBI_MAX_DEVICES; i++) {
295 ubi = ubi_devices[i];
296 if (ubi && MAJOR(ubi->cdev.dev) == major) {
297 ubi_assert(ubi->ref_count >= 0);
298 ubi->ref_count += 1;
299 get_device(&ubi->dev);
300 spin_unlock(&ubi_devices_lock);
301 return ubi;
302 }
303 }
304 spin_unlock(&ubi_devices_lock);
305
306 return NULL;
307 }
308
309 /**
310 * ubi_major2num - get UBI device number by character device major number.
311 * @major: major number
312 *
313 * This function searches UBI device number object by its major number. If UBI
314 * device was not found, this function returns -ENODEV, otherwise the UBI device
315 * number is returned.
316 */
ubi_major2num(int major)317 int ubi_major2num(int major)
318 {
319 int i, ubi_num = -ENODEV;
320
321 spin_lock(&ubi_devices_lock);
322 for (i = 0; i < UBI_MAX_DEVICES; i++) {
323 struct ubi_device *ubi = ubi_devices[i];
324
325 if (ubi && MAJOR(ubi->cdev.dev) == major) {
326 ubi_num = ubi->ubi_num;
327 break;
328 }
329 }
330 spin_unlock(&ubi_devices_lock);
331
332 return ubi_num;
333 }
334
335 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
dev_attribute_show(struct device * dev,struct device_attribute * attr,char * buf)336 static ssize_t dev_attribute_show(struct device *dev,
337 struct device_attribute *attr, char *buf)
338 {
339 ssize_t ret;
340 struct ubi_device *ubi;
341
342 /*
343 * The below code looks weird, but it actually makes sense. We get the
344 * UBI device reference from the contained 'struct ubi_device'. But it
345 * is unclear if the device was removed or not yet. Indeed, if the
346 * device was removed before we increased its reference count,
347 * 'ubi_get_device()' will return -ENODEV and we fail.
348 *
349 * Remember, 'struct ubi_device' is freed in the release function, so
350 * we still can use 'ubi->ubi_num'.
351 */
352 ubi = container_of(dev, struct ubi_device, dev);
353 ubi = ubi_get_device(ubi->ubi_num);
354 if (!ubi)
355 return -ENODEV;
356
357 if (attr == &dev_eraseblock_size)
358 ret = sprintf(buf, "%d\n", ubi->leb_size);
359 else if (attr == &dev_avail_eraseblocks)
360 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
361 else if (attr == &dev_total_eraseblocks)
362 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
363 else if (attr == &dev_volumes_count)
364 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
365 else if (attr == &dev_max_ec)
366 ret = sprintf(buf, "%d\n", ubi->max_ec);
367 else if (attr == &dev_reserved_for_bad)
368 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
369 else if (attr == &dev_bad_peb_count)
370 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
371 else if (attr == &dev_max_vol_count)
372 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
373 else if (attr == &dev_min_io_size)
374 ret = sprintf(buf, "%d\n", ubi->min_io_size);
375 else if (attr == &dev_bgt_enabled)
376 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
377 else if (attr == &dev_mtd_num)
378 ret = sprintf(buf, "%d\n", ubi->mtd->index);
379 else if (attr == &dev_ro_mode)
380 ret = sprintf(buf, "%d\n", ubi->ro_mode);
381 else
382 ret = -EINVAL;
383
384 ubi_put_device(ubi);
385 return ret;
386 }
387
388 static struct attribute *ubi_dev_attrs[] = {
389 &dev_eraseblock_size.attr,
390 &dev_avail_eraseblocks.attr,
391 &dev_total_eraseblocks.attr,
392 &dev_volumes_count.attr,
393 &dev_max_ec.attr,
394 &dev_reserved_for_bad.attr,
395 &dev_bad_peb_count.attr,
396 &dev_max_vol_count.attr,
397 &dev_min_io_size.attr,
398 &dev_bgt_enabled.attr,
399 &dev_mtd_num.attr,
400 &dev_ro_mode.attr,
401 NULL
402 };
403 ATTRIBUTE_GROUPS(ubi_dev);
404
dev_release(struct device * dev)405 static void dev_release(struct device *dev)
406 {
407 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
408
409 kfree(ubi);
410 }
411
412 /**
413 * kill_volumes - destroy all user volumes.
414 * @ubi: UBI device description object
415 */
kill_volumes(struct ubi_device * ubi)416 static void kill_volumes(struct ubi_device *ubi)
417 {
418 int i;
419
420 for (i = 0; i < ubi->vtbl_slots; i++)
421 if (ubi->volumes[i])
422 ubi_free_volume(ubi, ubi->volumes[i]);
423 }
424
425 /**
426 * uif_init - initialize user interfaces for an UBI device.
427 * @ubi: UBI device description object
428 *
429 * This function initializes various user interfaces for an UBI device. If the
430 * initialization fails at an early stage, this function frees all the
431 * resources it allocated, returns an error.
432 *
433 * This function returns zero in case of success and a negative error code in
434 * case of failure.
435 */
uif_init(struct ubi_device * ubi)436 static int uif_init(struct ubi_device *ubi)
437 {
438 int i, err;
439 dev_t dev;
440
441 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
442
443 /*
444 * Major numbers for the UBI character devices are allocated
445 * dynamically. Major numbers of volume character devices are
446 * equivalent to ones of the corresponding UBI character device. Minor
447 * numbers of UBI character devices are 0, while minor numbers of
448 * volume character devices start from 1. Thus, we allocate one major
449 * number and ubi->vtbl_slots + 1 minor numbers.
450 */
451 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
452 if (err) {
453 ubi_err(ubi, "cannot register UBI character devices");
454 return err;
455 }
456
457 ubi->dev.devt = dev;
458
459 ubi_assert(MINOR(dev) == 0);
460 cdev_init(&ubi->cdev, &ubi_cdev_operations);
461 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
462 ubi->cdev.owner = THIS_MODULE;
463
464 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
465 err = cdev_device_add(&ubi->cdev, &ubi->dev);
466 if (err)
467 goto out_unreg;
468
469 for (i = 0; i < ubi->vtbl_slots; i++)
470 if (ubi->volumes[i]) {
471 err = ubi_add_volume(ubi, ubi->volumes[i]);
472 if (err) {
473 ubi_err(ubi, "cannot add volume %d", i);
474 goto out_volumes;
475 }
476 }
477
478 return 0;
479
480 out_volumes:
481 kill_volumes(ubi);
482 cdev_device_del(&ubi->cdev, &ubi->dev);
483 out_unreg:
484 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
485 ubi_err(ubi, "cannot initialize UBI %s, error %d",
486 ubi->ubi_name, err);
487 return err;
488 }
489
490 /**
491 * uif_close - close user interfaces for an UBI device.
492 * @ubi: UBI device description object
493 *
494 * Note, since this function un-registers UBI volume device objects (@vol->dev),
495 * the memory allocated voe the volumes is freed as well (in the release
496 * function).
497 */
uif_close(struct ubi_device * ubi)498 static void uif_close(struct ubi_device *ubi)
499 {
500 kill_volumes(ubi);
501 cdev_device_del(&ubi->cdev, &ubi->dev);
502 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
503 }
504
505 /**
506 * ubi_free_internal_volumes - free internal volumes.
507 * @ubi: UBI device description object
508 */
ubi_free_internal_volumes(struct ubi_device * ubi)509 void ubi_free_internal_volumes(struct ubi_device *ubi)
510 {
511 int i;
512
513 for (i = ubi->vtbl_slots;
514 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
515 ubi_eba_replace_table(ubi->volumes[i], NULL);
516 ubi_fastmap_destroy_checkmap(ubi->volumes[i]);
517 kfree(ubi->volumes[i]);
518 }
519 }
520
get_bad_peb_limit(const struct ubi_device * ubi,int max_beb_per1024)521 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
522 {
523 int limit, device_pebs;
524 uint64_t device_size;
525
526 if (!max_beb_per1024) {
527 /*
528 * Since max_beb_per1024 has not been set by the user in either
529 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the
530 * limit if it is supported by the device.
531 */
532 limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size);
533 if (limit < 0)
534 return 0;
535 return limit;
536 }
537
538 /*
539 * Here we are using size of the entire flash chip and
540 * not just the MTD partition size because the maximum
541 * number of bad eraseblocks is a percentage of the
542 * whole device and bad eraseblocks are not fairly
543 * distributed over the flash chip. So the worst case
544 * is that all the bad eraseblocks of the chip are in
545 * the MTD partition we are attaching (ubi->mtd).
546 */
547 device_size = mtd_get_device_size(ubi->mtd);
548 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
549 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
550
551 /* Round it up */
552 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
553 limit += 1;
554
555 return limit;
556 }
557
558 /**
559 * io_init - initialize I/O sub-system for a given UBI device.
560 * @ubi: UBI device description object
561 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
562 *
563 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
564 * assumed:
565 * o EC header is always at offset zero - this cannot be changed;
566 * o VID header starts just after the EC header at the closest address
567 * aligned to @io->hdrs_min_io_size;
568 * o data starts just after the VID header at the closest address aligned to
569 * @io->min_io_size
570 *
571 * This function returns zero in case of success and a negative error code in
572 * case of failure.
573 */
io_init(struct ubi_device * ubi,int max_beb_per1024)574 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
575 {
576 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
577 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
578
579 if (ubi->mtd->numeraseregions != 0) {
580 /*
581 * Some flashes have several erase regions. Different regions
582 * may have different eraseblock size and other
583 * characteristics. It looks like mostly multi-region flashes
584 * have one "main" region and one or more small regions to
585 * store boot loader code or boot parameters or whatever. I
586 * guess we should just pick the largest region. But this is
587 * not implemented.
588 */
589 ubi_err(ubi, "multiple regions, not implemented");
590 return -EINVAL;
591 }
592
593 if (ubi->vid_hdr_offset < 0)
594 return -EINVAL;
595
596 /*
597 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
598 * physical eraseblocks maximum.
599 */
600
601 ubi->peb_size = ubi->mtd->erasesize;
602 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
603 ubi->flash_size = ubi->mtd->size;
604
605 if (mtd_can_have_bb(ubi->mtd)) {
606 ubi->bad_allowed = 1;
607 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
608 }
609
610 if (ubi->mtd->type == MTD_NORFLASH) {
611 ubi_assert(ubi->mtd->writesize == 1);
612 ubi->nor_flash = 1;
613 }
614
615 ubi->min_io_size = ubi->mtd->writesize;
616 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
617
618 /*
619 * Make sure minimal I/O unit is power of 2. Note, there is no
620 * fundamental reason for this assumption. It is just an optimization
621 * which allows us to avoid costly division operations.
622 */
623 if (!is_power_of_2(ubi->min_io_size)) {
624 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
625 ubi->min_io_size);
626 return -EINVAL;
627 }
628
629 ubi_assert(ubi->hdrs_min_io_size > 0);
630 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
631 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
632
633 ubi->max_write_size = ubi->mtd->writebufsize;
634 /*
635 * Maximum write size has to be greater or equivalent to min. I/O
636 * size, and be multiple of min. I/O size.
637 */
638 if (ubi->max_write_size < ubi->min_io_size ||
639 ubi->max_write_size % ubi->min_io_size ||
640 !is_power_of_2(ubi->max_write_size)) {
641 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
642 ubi->max_write_size, ubi->min_io_size);
643 return -EINVAL;
644 }
645
646 /* Calculate default aligned sizes of EC and VID headers */
647 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
648 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
649
650 dbg_gen("min_io_size %d", ubi->min_io_size);
651 dbg_gen("max_write_size %d", ubi->max_write_size);
652 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
653 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
654 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
655
656 if (ubi->vid_hdr_offset == 0)
657 /* Default offset */
658 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
659 ubi->ec_hdr_alsize;
660 else {
661 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
662 ~(ubi->hdrs_min_io_size - 1);
663 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
664 ubi->vid_hdr_aloffset;
665 }
666
667 /* Similar for the data offset */
668 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
669 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
670
671 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
672 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
673 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
674 dbg_gen("leb_start %d", ubi->leb_start);
675
676 /* The shift must be aligned to 32-bit boundary */
677 if (ubi->vid_hdr_shift % 4) {
678 ubi_err(ubi, "unaligned VID header shift %d",
679 ubi->vid_hdr_shift);
680 return -EINVAL;
681 }
682
683 /* Check sanity */
684 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
685 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
686 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
687 ubi->leb_start & (ubi->min_io_size - 1)) {
688 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
689 ubi->vid_hdr_offset, ubi->leb_start);
690 return -EINVAL;
691 }
692
693 /*
694 * Set maximum amount of physical erroneous eraseblocks to be 10%.
695 * Erroneous PEB are those which have read errors.
696 */
697 ubi->max_erroneous = ubi->peb_count / 10;
698 if (ubi->max_erroneous < 16)
699 ubi->max_erroneous = 16;
700 dbg_gen("max_erroneous %d", ubi->max_erroneous);
701
702 /*
703 * It may happen that EC and VID headers are situated in one minimal
704 * I/O unit. In this case we can only accept this UBI image in
705 * read-only mode.
706 */
707 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
708 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
709 ubi->ro_mode = 1;
710 }
711
712 ubi->leb_size = ubi->peb_size - ubi->leb_start;
713
714 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
715 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
716 ubi->mtd->index);
717 ubi->ro_mode = 1;
718 }
719
720 /*
721 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
722 * unfortunately, MTD does not provide this information. We should loop
723 * over all physical eraseblocks and invoke mtd->block_is_bad() for
724 * each physical eraseblock. So, we leave @ubi->bad_peb_count
725 * uninitialized so far.
726 */
727
728 return 0;
729 }
730
731 /**
732 * autoresize - re-size the volume which has the "auto-resize" flag set.
733 * @ubi: UBI device description object
734 * @vol_id: ID of the volume to re-size
735 *
736 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
737 * the volume table to the largest possible size. See comments in ubi-header.h
738 * for more description of the flag. Returns zero in case of success and a
739 * negative error code in case of failure.
740 */
autoresize(struct ubi_device * ubi,int vol_id)741 static int autoresize(struct ubi_device *ubi, int vol_id)
742 {
743 struct ubi_volume_desc desc;
744 struct ubi_volume *vol = ubi->volumes[vol_id];
745 int err, old_reserved_pebs = vol->reserved_pebs;
746
747 if (ubi->ro_mode) {
748 ubi_warn(ubi, "skip auto-resize because of R/O mode");
749 return 0;
750 }
751
752 /*
753 * Clear the auto-resize flag in the volume in-memory copy of the
754 * volume table, and 'ubi_resize_volume()' will propagate this change
755 * to the flash.
756 */
757 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
758
759 if (ubi->avail_pebs == 0) {
760 struct ubi_vtbl_record vtbl_rec;
761
762 /*
763 * No available PEBs to re-size the volume, clear the flag on
764 * flash and exit.
765 */
766 vtbl_rec = ubi->vtbl[vol_id];
767 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
768 if (err)
769 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
770 vol_id);
771 } else {
772 desc.vol = vol;
773 err = ubi_resize_volume(&desc,
774 old_reserved_pebs + ubi->avail_pebs);
775 if (err)
776 ubi_err(ubi, "cannot auto-resize volume %d",
777 vol_id);
778 }
779
780 if (err)
781 return err;
782
783 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
784 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
785 return 0;
786 }
787
788 /**
789 * ubi_attach_mtd_dev - attach an MTD device.
790 * @mtd: MTD device description object
791 * @ubi_num: number to assign to the new UBI device
792 * @vid_hdr_offset: VID header offset
793 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
794 *
795 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
796 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
797 * which case this function finds a vacant device number and assigns it
798 * automatically. Returns the new UBI device number in case of success and a
799 * negative error code in case of failure.
800 *
801 * Note, the invocations of this function has to be serialized by the
802 * @ubi_devices_mutex.
803 */
ubi_attach_mtd_dev(struct mtd_info * mtd,int ubi_num,int vid_hdr_offset,int max_beb_per1024)804 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
805 int vid_hdr_offset, int max_beb_per1024)
806 {
807 struct ubi_device *ubi;
808 int i, err;
809
810 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
811 return -EINVAL;
812
813 if (!max_beb_per1024)
814 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
815
816 /*
817 * Check if we already have the same MTD device attached.
818 *
819 * Note, this function assumes that UBI devices creations and deletions
820 * are serialized, so it does not take the &ubi_devices_lock.
821 */
822 for (i = 0; i < UBI_MAX_DEVICES; i++) {
823 ubi = ubi_devices[i];
824 if (ubi && mtd->index == ubi->mtd->index) {
825 pr_err("ubi: mtd%d is already attached to ubi%d\n",
826 mtd->index, i);
827 return -EEXIST;
828 }
829 }
830
831 /*
832 * Make sure this MTD device is not emulated on top of an UBI volume
833 * already. Well, generally this recursion works fine, but there are
834 * different problems like the UBI module takes a reference to itself
835 * by attaching (and thus, opening) the emulated MTD device. This
836 * results in inability to unload the module. And in general it makes
837 * no sense to attach emulated MTD devices, so we prohibit this.
838 */
839 if (mtd->type == MTD_UBIVOLUME) {
840 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",
841 mtd->index);
842 return -EINVAL;
843 }
844
845 /*
846 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
847 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
848 * will die soon and you will lose all your data.
849 */
850 if (mtd->type == MTD_MLCNANDFLASH) {
851 pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
852 mtd->index);
853 return -EINVAL;
854 }
855
856 if (ubi_num == UBI_DEV_NUM_AUTO) {
857 /* Search for an empty slot in the @ubi_devices array */
858 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
859 if (!ubi_devices[ubi_num])
860 break;
861 if (ubi_num == UBI_MAX_DEVICES) {
862 pr_err("ubi: only %d UBI devices may be created\n",
863 UBI_MAX_DEVICES);
864 return -ENFILE;
865 }
866 } else {
867 if (ubi_num >= UBI_MAX_DEVICES)
868 return -EINVAL;
869
870 /* Make sure ubi_num is not busy */
871 if (ubi_devices[ubi_num]) {
872 pr_err("ubi: ubi%i already exists\n", ubi_num);
873 return -EEXIST;
874 }
875 }
876
877 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
878 if (!ubi)
879 return -ENOMEM;
880
881 device_initialize(&ubi->dev);
882 ubi->dev.release = dev_release;
883 ubi->dev.class = &ubi_class;
884 ubi->dev.groups = ubi_dev_groups;
885
886 ubi->mtd = mtd;
887 ubi->ubi_num = ubi_num;
888 ubi->vid_hdr_offset = vid_hdr_offset;
889 ubi->autoresize_vol_id = -1;
890
891 #ifdef CONFIG_MTD_UBI_FASTMAP
892 ubi->fm_pool.used = ubi->fm_pool.size = 0;
893 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
894
895 /*
896 * fm_pool.max_size is 5% of the total number of PEBs but it's also
897 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
898 */
899 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
900 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
901 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
902 UBI_FM_MIN_POOL_SIZE);
903
904 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
905 ubi->fm_disabled = !fm_autoconvert;
906 if (fm_debug)
907 ubi_enable_dbg_chk_fastmap(ubi);
908
909 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
910 <= UBI_FM_MAX_START) {
911 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
912 UBI_FM_MAX_START);
913 ubi->fm_disabled = 1;
914 }
915
916 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
917 ubi_msg(ubi, "default fastmap WL pool size: %d",
918 ubi->fm_wl_pool.max_size);
919 #else
920 ubi->fm_disabled = 1;
921 #endif
922 mutex_init(&ubi->buf_mutex);
923 mutex_init(&ubi->ckvol_mutex);
924 mutex_init(&ubi->device_mutex);
925 spin_lock_init(&ubi->volumes_lock);
926 init_rwsem(&ubi->fm_protect);
927 init_rwsem(&ubi->fm_eba_sem);
928
929 ubi_msg(ubi, "attaching mtd%d", mtd->index);
930
931 err = io_init(ubi, max_beb_per1024);
932 if (err)
933 goto out_free;
934
935 err = -ENOMEM;
936 ubi->peb_buf = vmalloc(ubi->peb_size);
937 if (!ubi->peb_buf)
938 goto out_free;
939
940 #ifdef CONFIG_MTD_UBI_FASTMAP
941 ubi->fm_size = ubi_calc_fm_size(ubi);
942 ubi->fm_buf = vzalloc(ubi->fm_size);
943 if (!ubi->fm_buf)
944 goto out_free;
945 #endif
946 err = ubi_attach(ubi, 0);
947 if (err) {
948 ubi_err(ubi, "failed to attach mtd%d, error %d",
949 mtd->index, err);
950 goto out_free;
951 }
952
953 if (ubi->autoresize_vol_id != -1) {
954 err = autoresize(ubi, ubi->autoresize_vol_id);
955 if (err)
956 goto out_detach;
957 }
958
959 /* Make device "available" before it becomes accessible via sysfs */
960 ubi_devices[ubi_num] = ubi;
961
962 err = uif_init(ubi);
963 if (err)
964 goto out_detach;
965
966 err = ubi_debugfs_init_dev(ubi);
967 if (err)
968 goto out_uif;
969
970 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
971 if (IS_ERR(ubi->bgt_thread)) {
972 err = PTR_ERR(ubi->bgt_thread);
973 ubi_err(ubi, "cannot spawn \"%s\", error %d",
974 ubi->bgt_name, err);
975 goto out_debugfs;
976 }
977
978 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
979 mtd->index, mtd->name, ubi->flash_size >> 20);
980 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
981 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
982 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
983 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
984 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
985 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
986 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
987 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
988 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
989 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
990 ubi->vtbl_slots);
991 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
992 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
993 ubi->image_seq);
994 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
995 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
996
997 /*
998 * The below lock makes sure we do not race with 'ubi_thread()' which
999 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1000 */
1001 spin_lock(&ubi->wl_lock);
1002 ubi->thread_enabled = 1;
1003 wake_up_process(ubi->bgt_thread);
1004 spin_unlock(&ubi->wl_lock);
1005
1006 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1007 return ubi_num;
1008
1009 out_debugfs:
1010 ubi_debugfs_exit_dev(ubi);
1011 out_uif:
1012 uif_close(ubi);
1013 out_detach:
1014 ubi_devices[ubi_num] = NULL;
1015 ubi_wl_close(ubi);
1016 ubi_free_internal_volumes(ubi);
1017 vfree(ubi->vtbl);
1018 out_free:
1019 vfree(ubi->peb_buf);
1020 vfree(ubi->fm_buf);
1021 put_device(&ubi->dev);
1022 return err;
1023 }
1024
1025 /**
1026 * ubi_detach_mtd_dev - detach an MTD device.
1027 * @ubi_num: UBI device number to detach from
1028 * @anyway: detach MTD even if device reference count is not zero
1029 *
1030 * This function destroys an UBI device number @ubi_num and detaches the
1031 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1032 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1033 * exist.
1034 *
1035 * Note, the invocations of this function has to be serialized by the
1036 * @ubi_devices_mutex.
1037 */
ubi_detach_mtd_dev(int ubi_num,int anyway)1038 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1039 {
1040 struct ubi_device *ubi;
1041
1042 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1043 return -EINVAL;
1044
1045 ubi = ubi_get_device(ubi_num);
1046 if (!ubi)
1047 return -EINVAL;
1048
1049 spin_lock(&ubi_devices_lock);
1050 put_device(&ubi->dev);
1051 ubi->ref_count -= 1;
1052 if (ubi->ref_count) {
1053 if (!anyway) {
1054 spin_unlock(&ubi_devices_lock);
1055 return -EBUSY;
1056 }
1057 /* This may only happen if there is a bug */
1058 ubi_err(ubi, "%s reference count %d, destroy anyway",
1059 ubi->ubi_name, ubi->ref_count);
1060 }
1061 ubi_devices[ubi_num] = NULL;
1062 spin_unlock(&ubi_devices_lock);
1063
1064 ubi_assert(ubi_num == ubi->ubi_num);
1065 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1066 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1067 #ifdef CONFIG_MTD_UBI_FASTMAP
1068 /* If we don't write a new fastmap at detach time we lose all
1069 * EC updates that have been made since the last written fastmap.
1070 * In case of fastmap debugging we omit the update to simulate an
1071 * unclean shutdown. */
1072 if (!ubi_dbg_chk_fastmap(ubi))
1073 ubi_update_fastmap(ubi);
1074 #endif
1075 /*
1076 * Before freeing anything, we have to stop the background thread to
1077 * prevent it from doing anything on this device while we are freeing.
1078 */
1079 if (ubi->bgt_thread)
1080 kthread_stop(ubi->bgt_thread);
1081
1082 #ifdef CONFIG_MTD_UBI_FASTMAP
1083 cancel_work_sync(&ubi->fm_work);
1084 #endif
1085 ubi_debugfs_exit_dev(ubi);
1086 uif_close(ubi);
1087
1088 ubi_wl_close(ubi);
1089 ubi_free_internal_volumes(ubi);
1090 vfree(ubi->vtbl);
1091 vfree(ubi->peb_buf);
1092 vfree(ubi->fm_buf);
1093 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1094 put_mtd_device(ubi->mtd);
1095 put_device(&ubi->dev);
1096 return 0;
1097 }
1098
1099 /**
1100 * open_mtd_by_chdev - open an MTD device by its character device node path.
1101 * @mtd_dev: MTD character device node path
1102 *
1103 * This helper function opens an MTD device by its character node device path.
1104 * Returns MTD device description object in case of success and a negative
1105 * error code in case of failure.
1106 */
open_mtd_by_chdev(const char * mtd_dev)1107 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1108 {
1109 int err, minor;
1110 struct path path;
1111 struct kstat stat;
1112
1113 /* Probably this is an MTD character device node path */
1114 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1115 if (err)
1116 return ERR_PTR(err);
1117
1118 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1119 path_put(&path);
1120 if (err)
1121 return ERR_PTR(err);
1122
1123 /* MTD device number is defined by the major / minor numbers */
1124 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1125 return ERR_PTR(-EINVAL);
1126
1127 minor = MINOR(stat.rdev);
1128
1129 if (minor & 1)
1130 /*
1131 * Just do not think the "/dev/mtdrX" devices support is need,
1132 * so do not support them to avoid doing extra work.
1133 */
1134 return ERR_PTR(-EINVAL);
1135
1136 return get_mtd_device(NULL, minor / 2);
1137 }
1138
1139 /**
1140 * open_mtd_device - open MTD device by name, character device path, or number.
1141 * @mtd_dev: name, character device node path, or MTD device device number
1142 *
1143 * This function tries to open and MTD device described by @mtd_dev string,
1144 * which is first treated as ASCII MTD device number, and if it is not true, it
1145 * is treated as MTD device name, and if that is also not true, it is treated
1146 * as MTD character device node path. Returns MTD device description object in
1147 * case of success and a negative error code in case of failure.
1148 */
open_mtd_device(const char * mtd_dev)1149 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1150 {
1151 struct mtd_info *mtd;
1152 int mtd_num;
1153 char *endp;
1154
1155 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1156 if (*endp != '\0' || mtd_dev == endp) {
1157 /*
1158 * This does not look like an ASCII integer, probably this is
1159 * MTD device name.
1160 */
1161 mtd = get_mtd_device_nm(mtd_dev);
1162 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1163 /* Probably this is an MTD character device node path */
1164 mtd = open_mtd_by_chdev(mtd_dev);
1165 } else
1166 mtd = get_mtd_device(NULL, mtd_num);
1167
1168 return mtd;
1169 }
1170
ubi_init(void)1171 static int __init ubi_init(void)
1172 {
1173 int err, i, k;
1174
1175 /* Ensure that EC and VID headers have correct size */
1176 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1177 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1178
1179 if (mtd_devs > UBI_MAX_DEVICES) {
1180 pr_err("UBI error: too many MTD devices, maximum is %d\n",
1181 UBI_MAX_DEVICES);
1182 return -EINVAL;
1183 }
1184
1185 /* Create base sysfs directory and sysfs files */
1186 err = class_register(&ubi_class);
1187 if (err < 0)
1188 return err;
1189
1190 err = misc_register(&ubi_ctrl_cdev);
1191 if (err) {
1192 pr_err("UBI error: cannot register device\n");
1193 goto out;
1194 }
1195
1196 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1197 sizeof(struct ubi_wl_entry),
1198 0, 0, NULL);
1199 if (!ubi_wl_entry_slab) {
1200 err = -ENOMEM;
1201 goto out_dev_unreg;
1202 }
1203
1204 err = ubi_debugfs_init();
1205 if (err)
1206 goto out_slab;
1207
1208
1209 /* Attach MTD devices */
1210 for (i = 0; i < mtd_devs; i++) {
1211 struct mtd_dev_param *p = &mtd_dev_param[i];
1212 struct mtd_info *mtd;
1213
1214 cond_resched();
1215
1216 mtd = open_mtd_device(p->name);
1217 if (IS_ERR(mtd)) {
1218 err = PTR_ERR(mtd);
1219 pr_err("UBI error: cannot open mtd %s, error %d\n",
1220 p->name, err);
1221 /* See comment below re-ubi_is_module(). */
1222 if (ubi_is_module())
1223 goto out_detach;
1224 continue;
1225 }
1226
1227 mutex_lock(&ubi_devices_mutex);
1228 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1229 p->vid_hdr_offs, p->max_beb_per1024);
1230 mutex_unlock(&ubi_devices_mutex);
1231 if (err < 0) {
1232 pr_err("UBI error: cannot attach mtd%d\n",
1233 mtd->index);
1234 put_mtd_device(mtd);
1235
1236 /*
1237 * Originally UBI stopped initializing on any error.
1238 * However, later on it was found out that this
1239 * behavior is not very good when UBI is compiled into
1240 * the kernel and the MTD devices to attach are passed
1241 * through the command line. Indeed, UBI failure
1242 * stopped whole boot sequence.
1243 *
1244 * To fix this, we changed the behavior for the
1245 * non-module case, but preserved the old behavior for
1246 * the module case, just for compatibility. This is a
1247 * little inconsistent, though.
1248 */
1249 if (ubi_is_module())
1250 goto out_detach;
1251 }
1252 }
1253
1254 err = ubiblock_init();
1255 if (err) {
1256 pr_err("UBI error: block: cannot initialize, error %d\n", err);
1257
1258 /* See comment above re-ubi_is_module(). */
1259 if (ubi_is_module())
1260 goto out_detach;
1261 }
1262
1263 return 0;
1264
1265 out_detach:
1266 for (k = 0; k < i; k++)
1267 if (ubi_devices[k]) {
1268 mutex_lock(&ubi_devices_mutex);
1269 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1270 mutex_unlock(&ubi_devices_mutex);
1271 }
1272 ubi_debugfs_exit();
1273 out_slab:
1274 kmem_cache_destroy(ubi_wl_entry_slab);
1275 out_dev_unreg:
1276 misc_deregister(&ubi_ctrl_cdev);
1277 out:
1278 class_unregister(&ubi_class);
1279 pr_err("UBI error: cannot initialize UBI, error %d\n", err);
1280 return err;
1281 }
1282 late_initcall(ubi_init);
1283
ubi_exit(void)1284 static void __exit ubi_exit(void)
1285 {
1286 int i;
1287
1288 ubiblock_exit();
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_unregister(&ubi_class);
1300 }
1301 module_exit(ubi_exit);
1302
1303 /**
1304 * bytes_str_to_int - convert a number of bytes string into an integer.
1305 * @str: the string to convert
1306 *
1307 * This function returns positive resulting integer in case of success and a
1308 * negative error code in case of failure.
1309 */
bytes_str_to_int(const char * str)1310 static int bytes_str_to_int(const char *str)
1311 {
1312 char *endp;
1313 unsigned long result;
1314
1315 result = simple_strtoul(str, &endp, 0);
1316 if (str == endp || result >= INT_MAX) {
1317 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1318 return -EINVAL;
1319 }
1320
1321 switch (*endp) {
1322 case 'G':
1323 result *= 1024;
1324 /* fall through */
1325 case 'M':
1326 result *= 1024;
1327 /* fall through */
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 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1336 return -EINVAL;
1337 }
1338
1339 return result;
1340 }
1341
1342 /**
1343 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1344 * @val: the parameter value to parse
1345 * @kp: not used
1346 *
1347 * This function returns zero in case of success and a negative error code in
1348 * case of error.
1349 */
ubi_mtd_param_parse(const char * val,const struct kernel_param * kp)1350 static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
1351 {
1352 int i, len;
1353 struct mtd_dev_param *p;
1354 char buf[MTD_PARAM_LEN_MAX];
1355 char *pbuf = &buf[0];
1356 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1357
1358 if (!val)
1359 return -EINVAL;
1360
1361 if (mtd_devs == UBI_MAX_DEVICES) {
1362 pr_err("UBI error: too many parameters, max. is %d\n",
1363 UBI_MAX_DEVICES);
1364 return -EINVAL;
1365 }
1366
1367 len = strnlen(val, MTD_PARAM_LEN_MAX);
1368 if (len == MTD_PARAM_LEN_MAX) {
1369 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1370 val, MTD_PARAM_LEN_MAX);
1371 return -EINVAL;
1372 }
1373
1374 if (len == 0) {
1375 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1376 return 0;
1377 }
1378
1379 strcpy(buf, val);
1380
1381 /* Get rid of the final newline */
1382 if (buf[len - 1] == '\n')
1383 buf[len - 1] = '\0';
1384
1385 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1386 tokens[i] = strsep(&pbuf, ",");
1387
1388 if (pbuf) {
1389 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1390 return -EINVAL;
1391 }
1392
1393 p = &mtd_dev_param[mtd_devs];
1394 strcpy(&p->name[0], tokens[0]);
1395
1396 token = tokens[1];
1397 if (token) {
1398 p->vid_hdr_offs = bytes_str_to_int(token);
1399
1400 if (p->vid_hdr_offs < 0)
1401 return p->vid_hdr_offs;
1402 }
1403
1404 token = tokens[2];
1405 if (token) {
1406 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1407
1408 if (err) {
1409 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1410 token);
1411 return -EINVAL;
1412 }
1413 }
1414
1415 token = tokens[3];
1416 if (token) {
1417 int err = kstrtoint(token, 10, &p->ubi_num);
1418
1419 if (err) {
1420 pr_err("UBI error: bad value for ubi_num parameter: %s",
1421 token);
1422 return -EINVAL;
1423 }
1424 } else
1425 p->ubi_num = UBI_DEV_NUM_AUTO;
1426
1427 mtd_devs += 1;
1428 return 0;
1429 }
1430
1431 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1432 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1433 "Multiple \"mtd\" parameters may be specified.\n"
1434 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1435 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1436 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1437 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1438 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1439 "\n"
1440 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1441 "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"
1442 "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"
1443 "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"
1444 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1445 #ifdef CONFIG_MTD_UBI_FASTMAP
1446 module_param(fm_autoconvert, bool, 0644);
1447 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1448 module_param(fm_debug, bool, 0);
1449 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1450 #endif
1451 MODULE_VERSION(__stringify(UBI_VERSION));
1452 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1453 MODULE_AUTHOR("Artem Bityutskiy");
1454 MODULE_LICENSE("GPL");
1455