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
354 if (attr == &dev_eraseblock_size)
355 ret = sprintf(buf, "%d\n", ubi->leb_size);
356 else if (attr == &dev_avail_eraseblocks)
357 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
358 else if (attr == &dev_total_eraseblocks)
359 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
360 else if (attr == &dev_volumes_count)
361 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
362 else if (attr == &dev_max_ec)
363 ret = sprintf(buf, "%d\n", ubi->max_ec);
364 else if (attr == &dev_reserved_for_bad)
365 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
366 else if (attr == &dev_bad_peb_count)
367 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
368 else if (attr == &dev_max_vol_count)
369 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
370 else if (attr == &dev_min_io_size)
371 ret = sprintf(buf, "%d\n", ubi->min_io_size);
372 else if (attr == &dev_bgt_enabled)
373 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
374 else if (attr == &dev_mtd_num)
375 ret = sprintf(buf, "%d\n", ubi->mtd->index);
376 else if (attr == &dev_ro_mode)
377 ret = sprintf(buf, "%d\n", ubi->ro_mode);
378 else
379 ret = -EINVAL;
380
381 return ret;
382 }
383
384 static struct attribute *ubi_dev_attrs[] = {
385 &dev_eraseblock_size.attr,
386 &dev_avail_eraseblocks.attr,
387 &dev_total_eraseblocks.attr,
388 &dev_volumes_count.attr,
389 &dev_max_ec.attr,
390 &dev_reserved_for_bad.attr,
391 &dev_bad_peb_count.attr,
392 &dev_max_vol_count.attr,
393 &dev_min_io_size.attr,
394 &dev_bgt_enabled.attr,
395 &dev_mtd_num.attr,
396 &dev_ro_mode.attr,
397 NULL
398 };
399 ATTRIBUTE_GROUPS(ubi_dev);
400
dev_release(struct device * dev)401 static void dev_release(struct device *dev)
402 {
403 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
404
405 kfree(ubi);
406 }
407
408 /**
409 * kill_volumes - destroy all user volumes.
410 * @ubi: UBI device description object
411 */
kill_volumes(struct ubi_device * ubi)412 static void kill_volumes(struct ubi_device *ubi)
413 {
414 int i;
415
416 for (i = 0; i < ubi->vtbl_slots; i++)
417 if (ubi->volumes[i])
418 ubi_free_volume(ubi, ubi->volumes[i]);
419 }
420
421 /**
422 * uif_init - initialize user interfaces for an UBI device.
423 * @ubi: UBI device description object
424 *
425 * This function initializes various user interfaces for an UBI device. If the
426 * initialization fails at an early stage, this function frees all the
427 * resources it allocated, returns an error.
428 *
429 * This function returns zero in case of success and a negative error code in
430 * case of failure.
431 */
uif_init(struct ubi_device * ubi)432 static int uif_init(struct ubi_device *ubi)
433 {
434 int i, err;
435 dev_t dev;
436
437 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
438
439 /*
440 * Major numbers for the UBI character devices are allocated
441 * dynamically. Major numbers of volume character devices are
442 * equivalent to ones of the corresponding UBI character device. Minor
443 * numbers of UBI character devices are 0, while minor numbers of
444 * volume character devices start from 1. Thus, we allocate one major
445 * number and ubi->vtbl_slots + 1 minor numbers.
446 */
447 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
448 if (err) {
449 ubi_err(ubi, "cannot register UBI character devices");
450 return err;
451 }
452
453 ubi->dev.devt = dev;
454
455 ubi_assert(MINOR(dev) == 0);
456 cdev_init(&ubi->cdev, &ubi_cdev_operations);
457 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
458 ubi->cdev.owner = THIS_MODULE;
459
460 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
461 err = cdev_device_add(&ubi->cdev, &ubi->dev);
462 if (err)
463 goto out_unreg;
464
465 for (i = 0; i < ubi->vtbl_slots; i++)
466 if (ubi->volumes[i]) {
467 err = ubi_add_volume(ubi, ubi->volumes[i]);
468 if (err) {
469 ubi_err(ubi, "cannot add volume %d", i);
470 goto out_volumes;
471 }
472 }
473
474 return 0;
475
476 out_volumes:
477 kill_volumes(ubi);
478 cdev_device_del(&ubi->cdev, &ubi->dev);
479 out_unreg:
480 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
481 ubi_err(ubi, "cannot initialize UBI %s, error %d",
482 ubi->ubi_name, err);
483 return err;
484 }
485
486 /**
487 * uif_close - close user interfaces for an UBI device.
488 * @ubi: UBI device description object
489 *
490 * Note, since this function un-registers UBI volume device objects (@vol->dev),
491 * the memory allocated voe the volumes is freed as well (in the release
492 * function).
493 */
uif_close(struct ubi_device * ubi)494 static void uif_close(struct ubi_device *ubi)
495 {
496 kill_volumes(ubi);
497 cdev_device_del(&ubi->cdev, &ubi->dev);
498 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
499 }
500
501 /**
502 * ubi_free_volumes_from - free volumes from specific index.
503 * @ubi: UBI device description object
504 * @from: the start index used for volume free.
505 */
ubi_free_volumes_from(struct ubi_device * ubi,int from)506 static void ubi_free_volumes_from(struct ubi_device *ubi, int from)
507 {
508 int i;
509
510 for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
511 if (!ubi->volumes[i])
512 continue;
513 ubi_eba_replace_table(ubi->volumes[i], NULL);
514 ubi_fastmap_destroy_checkmap(ubi->volumes[i]);
515 kfree(ubi->volumes[i]);
516 ubi->volumes[i] = NULL;
517 }
518 }
519
520 /**
521 * ubi_free_all_volumes - free all volumes.
522 * @ubi: UBI device description object
523 */
ubi_free_all_volumes(struct ubi_device * ubi)524 void ubi_free_all_volumes(struct ubi_device *ubi)
525 {
526 ubi_free_volumes_from(ubi, 0);
527 }
528
529 /**
530 * ubi_free_internal_volumes - free internal volumes.
531 * @ubi: UBI device description object
532 */
ubi_free_internal_volumes(struct ubi_device * ubi)533 void ubi_free_internal_volumes(struct ubi_device *ubi)
534 {
535 ubi_free_volumes_from(ubi, ubi->vtbl_slots);
536 }
537
get_bad_peb_limit(const struct ubi_device * ubi,int max_beb_per1024)538 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
539 {
540 int limit, device_pebs;
541 uint64_t device_size;
542
543 if (!max_beb_per1024) {
544 /*
545 * Since max_beb_per1024 has not been set by the user in either
546 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the
547 * limit if it is supported by the device.
548 */
549 limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size);
550 if (limit < 0)
551 return 0;
552 return limit;
553 }
554
555 /*
556 * Here we are using size of the entire flash chip and
557 * not just the MTD partition size because the maximum
558 * number of bad eraseblocks is a percentage of the
559 * whole device and bad eraseblocks are not fairly
560 * distributed over the flash chip. So the worst case
561 * is that all the bad eraseblocks of the chip are in
562 * the MTD partition we are attaching (ubi->mtd).
563 */
564 device_size = mtd_get_device_size(ubi->mtd);
565 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
566 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
567
568 /* Round it up */
569 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
570 limit += 1;
571
572 return limit;
573 }
574
575 /**
576 * io_init - initialize I/O sub-system for a given UBI device.
577 * @ubi: UBI device description object
578 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
579 *
580 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
581 * assumed:
582 * o EC header is always at offset zero - this cannot be changed;
583 * o VID header starts just after the EC header at the closest address
584 * aligned to @io->hdrs_min_io_size;
585 * o data starts just after the VID header at the closest address aligned to
586 * @io->min_io_size
587 *
588 * This function returns zero in case of success and a negative error code in
589 * case of failure.
590 */
io_init(struct ubi_device * ubi,int max_beb_per1024)591 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
592 {
593 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
594 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
595
596 if (ubi->mtd->numeraseregions != 0) {
597 /*
598 * Some flashes have several erase regions. Different regions
599 * may have different eraseblock size and other
600 * characteristics. It looks like mostly multi-region flashes
601 * have one "main" region and one or more small regions to
602 * store boot loader code or boot parameters or whatever. I
603 * guess we should just pick the largest region. But this is
604 * not implemented.
605 */
606 ubi_err(ubi, "multiple regions, not implemented");
607 return -EINVAL;
608 }
609
610 if (ubi->vid_hdr_offset < 0)
611 return -EINVAL;
612
613 /*
614 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
615 * physical eraseblocks maximum.
616 */
617
618 ubi->peb_size = ubi->mtd->erasesize;
619 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
620 ubi->flash_size = ubi->mtd->size;
621
622 if (mtd_can_have_bb(ubi->mtd)) {
623 ubi->bad_allowed = 1;
624 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
625 }
626
627 if (ubi->mtd->type == MTD_NORFLASH) {
628 ubi_assert(ubi->mtd->writesize == 1);
629 ubi->nor_flash = 1;
630 }
631
632 ubi->min_io_size = ubi->mtd->writesize;
633 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
634
635 /*
636 * Make sure minimal I/O unit is power of 2. Note, there is no
637 * fundamental reason for this assumption. It is just an optimization
638 * which allows us to avoid costly division operations.
639 */
640 if (!is_power_of_2(ubi->min_io_size)) {
641 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
642 ubi->min_io_size);
643 return -EINVAL;
644 }
645
646 ubi_assert(ubi->hdrs_min_io_size > 0);
647 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
648 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
649
650 ubi->max_write_size = ubi->mtd->writebufsize;
651 /*
652 * Maximum write size has to be greater or equivalent to min. I/O
653 * size, and be multiple of min. I/O size.
654 */
655 if (ubi->max_write_size < ubi->min_io_size ||
656 ubi->max_write_size % ubi->min_io_size ||
657 !is_power_of_2(ubi->max_write_size)) {
658 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
659 ubi->max_write_size, ubi->min_io_size);
660 return -EINVAL;
661 }
662
663 /* Calculate default aligned sizes of EC and VID headers */
664 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
665 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
666
667 dbg_gen("min_io_size %d", ubi->min_io_size);
668 dbg_gen("max_write_size %d", ubi->max_write_size);
669 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
670 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
671 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
672
673 if (ubi->vid_hdr_offset == 0)
674 /* Default offset */
675 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
676 ubi->ec_hdr_alsize;
677 else {
678 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
679 ~(ubi->hdrs_min_io_size - 1);
680 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
681 ubi->vid_hdr_aloffset;
682 }
683
684 /* Similar for the data offset */
685 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
686 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
687
688 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
689 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
690 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
691 dbg_gen("leb_start %d", ubi->leb_start);
692
693 /* The shift must be aligned to 32-bit boundary */
694 if (ubi->vid_hdr_shift % 4) {
695 ubi_err(ubi, "unaligned VID header shift %d",
696 ubi->vid_hdr_shift);
697 return -EINVAL;
698 }
699
700 /* Check sanity */
701 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
702 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
703 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
704 ubi->leb_start & (ubi->min_io_size - 1)) {
705 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
706 ubi->vid_hdr_offset, ubi->leb_start);
707 return -EINVAL;
708 }
709
710 /*
711 * Set maximum amount of physical erroneous eraseblocks to be 10%.
712 * Erroneous PEB are those which have read errors.
713 */
714 ubi->max_erroneous = ubi->peb_count / 10;
715 if (ubi->max_erroneous < 16)
716 ubi->max_erroneous = 16;
717 dbg_gen("max_erroneous %d", ubi->max_erroneous);
718
719 /*
720 * It may happen that EC and VID headers are situated in one minimal
721 * I/O unit. In this case we can only accept this UBI image in
722 * read-only mode.
723 */
724 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
725 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
726 ubi->ro_mode = 1;
727 }
728
729 ubi->leb_size = ubi->peb_size - ubi->leb_start;
730
731 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
732 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
733 ubi->mtd->index);
734 ubi->ro_mode = 1;
735 }
736
737 /*
738 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
739 * unfortunately, MTD does not provide this information. We should loop
740 * over all physical eraseblocks and invoke mtd->block_is_bad() for
741 * each physical eraseblock. So, we leave @ubi->bad_peb_count
742 * uninitialized so far.
743 */
744
745 return 0;
746 }
747
748 /**
749 * autoresize - re-size the volume which has the "auto-resize" flag set.
750 * @ubi: UBI device description object
751 * @vol_id: ID of the volume to re-size
752 *
753 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
754 * the volume table to the largest possible size. See comments in ubi-header.h
755 * for more description of the flag. Returns zero in case of success and a
756 * negative error code in case of failure.
757 */
autoresize(struct ubi_device * ubi,int vol_id)758 static int autoresize(struct ubi_device *ubi, int vol_id)
759 {
760 struct ubi_volume_desc desc;
761 struct ubi_volume *vol = ubi->volumes[vol_id];
762 int err, old_reserved_pebs = vol->reserved_pebs;
763
764 if (ubi->ro_mode) {
765 ubi_warn(ubi, "skip auto-resize because of R/O mode");
766 return 0;
767 }
768
769 /*
770 * Clear the auto-resize flag in the volume in-memory copy of the
771 * volume table, and 'ubi_resize_volume()' will propagate this change
772 * to the flash.
773 */
774 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
775
776 if (ubi->avail_pebs == 0) {
777 struct ubi_vtbl_record vtbl_rec;
778
779 /*
780 * No available PEBs to re-size the volume, clear the flag on
781 * flash and exit.
782 */
783 vtbl_rec = ubi->vtbl[vol_id];
784 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
785 if (err)
786 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
787 vol_id);
788 } else {
789 desc.vol = vol;
790 err = ubi_resize_volume(&desc,
791 old_reserved_pebs + ubi->avail_pebs);
792 if (err)
793 ubi_err(ubi, "cannot auto-resize volume %d",
794 vol_id);
795 }
796
797 if (err)
798 return err;
799
800 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
801 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
802 return 0;
803 }
804
805 /**
806 * ubi_attach_mtd_dev - attach an MTD device.
807 * @mtd: MTD device description object
808 * @ubi_num: number to assign to the new UBI device
809 * @vid_hdr_offset: VID header offset
810 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
811 *
812 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
813 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
814 * which case this function finds a vacant device number and assigns it
815 * automatically. Returns the new UBI device number in case of success and a
816 * negative error code in case of failure.
817 *
818 * Note, the invocations of this function has to be serialized by the
819 * @ubi_devices_mutex.
820 */
ubi_attach_mtd_dev(struct mtd_info * mtd,int ubi_num,int vid_hdr_offset,int max_beb_per1024)821 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
822 int vid_hdr_offset, int max_beb_per1024)
823 {
824 struct ubi_device *ubi;
825 int i, err;
826
827 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
828 return -EINVAL;
829
830 if (!max_beb_per1024)
831 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
832
833 /*
834 * Check if we already have the same MTD device attached.
835 *
836 * Note, this function assumes that UBI devices creations and deletions
837 * are serialized, so it does not take the &ubi_devices_lock.
838 */
839 for (i = 0; i < UBI_MAX_DEVICES; i++) {
840 ubi = ubi_devices[i];
841 if (ubi && mtd->index == ubi->mtd->index) {
842 pr_err("ubi: mtd%d is already attached to ubi%d\n",
843 mtd->index, i);
844 return -EEXIST;
845 }
846 }
847
848 /*
849 * Make sure this MTD device is not emulated on top of an UBI volume
850 * already. Well, generally this recursion works fine, but there are
851 * different problems like the UBI module takes a reference to itself
852 * by attaching (and thus, opening) the emulated MTD device. This
853 * results in inability to unload the module. And in general it makes
854 * no sense to attach emulated MTD devices, so we prohibit this.
855 */
856 if (mtd->type == MTD_UBIVOLUME) {
857 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",
858 mtd->index);
859 return -EINVAL;
860 }
861
862 /*
863 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
864 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
865 * will die soon and you will lose all your data.
866 * Relax this rule if the partition we're attaching to operates in SLC
867 * mode.
868 */
869 if (mtd->type == MTD_MLCNANDFLASH &&
870 !(mtd->flags & MTD_SLC_ON_MLC_EMULATION)) {
871 pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
872 mtd->index);
873 return -EINVAL;
874 }
875
876 if (ubi_num == UBI_DEV_NUM_AUTO) {
877 /* Search for an empty slot in the @ubi_devices array */
878 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
879 if (!ubi_devices[ubi_num])
880 break;
881 if (ubi_num == UBI_MAX_DEVICES) {
882 pr_err("ubi: only %d UBI devices may be created\n",
883 UBI_MAX_DEVICES);
884 return -ENFILE;
885 }
886 } else {
887 if (ubi_num >= UBI_MAX_DEVICES)
888 return -EINVAL;
889
890 /* Make sure ubi_num is not busy */
891 if (ubi_devices[ubi_num]) {
892 pr_err("ubi: ubi%i already exists\n", ubi_num);
893 return -EEXIST;
894 }
895 }
896
897 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
898 if (!ubi)
899 return -ENOMEM;
900
901 device_initialize(&ubi->dev);
902 ubi->dev.release = dev_release;
903 ubi->dev.class = &ubi_class;
904 ubi->dev.groups = ubi_dev_groups;
905
906 ubi->mtd = mtd;
907 ubi->ubi_num = ubi_num;
908 ubi->vid_hdr_offset = vid_hdr_offset;
909 ubi->autoresize_vol_id = -1;
910
911 #ifdef CONFIG_MTD_UBI_FASTMAP
912 ubi->fm_pool.used = ubi->fm_pool.size = 0;
913 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
914
915 /*
916 * fm_pool.max_size is 5% of the total number of PEBs but it's also
917 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
918 */
919 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
920 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
921 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
922 UBI_FM_MIN_POOL_SIZE);
923
924 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
925 ubi->fm_disabled = !fm_autoconvert;
926 if (fm_debug)
927 ubi_enable_dbg_chk_fastmap(ubi);
928
929 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
930 <= UBI_FM_MAX_START) {
931 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
932 UBI_FM_MAX_START);
933 ubi->fm_disabled = 1;
934 }
935
936 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
937 ubi_msg(ubi, "default fastmap WL pool size: %d",
938 ubi->fm_wl_pool.max_size);
939 #else
940 ubi->fm_disabled = 1;
941 #endif
942 mutex_init(&ubi->buf_mutex);
943 mutex_init(&ubi->ckvol_mutex);
944 mutex_init(&ubi->device_mutex);
945 spin_lock_init(&ubi->volumes_lock);
946 init_rwsem(&ubi->fm_protect);
947 init_rwsem(&ubi->fm_eba_sem);
948
949 ubi_msg(ubi, "attaching mtd%d", mtd->index);
950
951 err = io_init(ubi, max_beb_per1024);
952 if (err)
953 goto out_free;
954
955 err = -ENOMEM;
956 ubi->peb_buf = vmalloc(ubi->peb_size);
957 if (!ubi->peb_buf)
958 goto out_free;
959
960 #ifdef CONFIG_MTD_UBI_FASTMAP
961 ubi->fm_size = ubi_calc_fm_size(ubi);
962 ubi->fm_buf = vzalloc(ubi->fm_size);
963 if (!ubi->fm_buf)
964 goto out_free;
965 #endif
966 err = ubi_attach(ubi, 0);
967 if (err) {
968 ubi_err(ubi, "failed to attach mtd%d, error %d",
969 mtd->index, err);
970 goto out_free;
971 }
972
973 if (ubi->autoresize_vol_id != -1) {
974 err = autoresize(ubi, ubi->autoresize_vol_id);
975 if (err)
976 goto out_detach;
977 }
978
979 err = uif_init(ubi);
980 if (err)
981 goto out_detach;
982
983 err = ubi_debugfs_init_dev(ubi);
984 if (err)
985 goto out_uif;
986
987 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
988 if (IS_ERR(ubi->bgt_thread)) {
989 err = PTR_ERR(ubi->bgt_thread);
990 ubi_err(ubi, "cannot spawn \"%s\", error %d",
991 ubi->bgt_name, err);
992 goto out_debugfs;
993 }
994
995 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
996 mtd->index, mtd->name, ubi->flash_size >> 20);
997 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
998 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
999 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
1000 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
1001 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
1002 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
1003 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
1004 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1005 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
1006 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
1007 ubi->vtbl_slots);
1008 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1009 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1010 ubi->image_seq);
1011 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1012 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1013
1014 /*
1015 * The below lock makes sure we do not race with 'ubi_thread()' which
1016 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1017 */
1018 spin_lock(&ubi->wl_lock);
1019 ubi->thread_enabled = 1;
1020 wake_up_process(ubi->bgt_thread);
1021 spin_unlock(&ubi->wl_lock);
1022
1023 ubi_devices[ubi_num] = ubi;
1024 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1025 return ubi_num;
1026
1027 out_debugfs:
1028 ubi_debugfs_exit_dev(ubi);
1029 out_uif:
1030 uif_close(ubi);
1031 out_detach:
1032 ubi_wl_close(ubi);
1033 ubi_free_all_volumes(ubi);
1034 vfree(ubi->vtbl);
1035 out_free:
1036 vfree(ubi->peb_buf);
1037 vfree(ubi->fm_buf);
1038 put_device(&ubi->dev);
1039 return err;
1040 }
1041
1042 /**
1043 * ubi_detach_mtd_dev - detach an MTD device.
1044 * @ubi_num: UBI device number to detach from
1045 * @anyway: detach MTD even if device reference count is not zero
1046 *
1047 * This function destroys an UBI device number @ubi_num and detaches the
1048 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1049 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1050 * exist.
1051 *
1052 * Note, the invocations of this function has to be serialized by the
1053 * @ubi_devices_mutex.
1054 */
ubi_detach_mtd_dev(int ubi_num,int anyway)1055 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1056 {
1057 struct ubi_device *ubi;
1058
1059 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1060 return -EINVAL;
1061
1062 ubi = ubi_get_device(ubi_num);
1063 if (!ubi)
1064 return -EINVAL;
1065
1066 spin_lock(&ubi_devices_lock);
1067 put_device(&ubi->dev);
1068 ubi->ref_count -= 1;
1069 if (ubi->ref_count) {
1070 if (!anyway) {
1071 spin_unlock(&ubi_devices_lock);
1072 return -EBUSY;
1073 }
1074 /* This may only happen if there is a bug */
1075 ubi_err(ubi, "%s reference count %d, destroy anyway",
1076 ubi->ubi_name, ubi->ref_count);
1077 }
1078 ubi_devices[ubi_num] = NULL;
1079 spin_unlock(&ubi_devices_lock);
1080
1081 ubi_assert(ubi_num == ubi->ubi_num);
1082 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1083 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1084 #ifdef CONFIG_MTD_UBI_FASTMAP
1085 /* If we don't write a new fastmap at detach time we lose all
1086 * EC updates that have been made since the last written fastmap.
1087 * In case of fastmap debugging we omit the update to simulate an
1088 * unclean shutdown. */
1089 if (!ubi_dbg_chk_fastmap(ubi))
1090 ubi_update_fastmap(ubi);
1091 #endif
1092 /*
1093 * Before freeing anything, we have to stop the background thread to
1094 * prevent it from doing anything on this device while we are freeing.
1095 */
1096 if (ubi->bgt_thread)
1097 kthread_stop(ubi->bgt_thread);
1098
1099 #ifdef CONFIG_MTD_UBI_FASTMAP
1100 cancel_work_sync(&ubi->fm_work);
1101 #endif
1102 ubi_debugfs_exit_dev(ubi);
1103 uif_close(ubi);
1104
1105 ubi_wl_close(ubi);
1106 ubi_free_internal_volumes(ubi);
1107 vfree(ubi->vtbl);
1108 vfree(ubi->peb_buf);
1109 vfree(ubi->fm_buf);
1110 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1111 put_mtd_device(ubi->mtd);
1112 put_device(&ubi->dev);
1113 return 0;
1114 }
1115
1116 /**
1117 * open_mtd_by_chdev - open an MTD device by its character device node path.
1118 * @mtd_dev: MTD character device node path
1119 *
1120 * This helper function opens an MTD device by its character node device path.
1121 * Returns MTD device description object in case of success and a negative
1122 * error code in case of failure.
1123 */
open_mtd_by_chdev(const char * mtd_dev)1124 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1125 {
1126 int err, minor;
1127 struct path path;
1128 struct kstat stat;
1129
1130 /* Probably this is an MTD character device node path */
1131 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1132 if (err)
1133 return ERR_PTR(err);
1134
1135 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1136 path_put(&path);
1137 if (err)
1138 return ERR_PTR(err);
1139
1140 /* MTD device number is defined by the major / minor numbers */
1141 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1142 return ERR_PTR(-EINVAL);
1143
1144 minor = MINOR(stat.rdev);
1145
1146 if (minor & 1)
1147 /*
1148 * Just do not think the "/dev/mtdrX" devices support is need,
1149 * so do not support them to avoid doing extra work.
1150 */
1151 return ERR_PTR(-EINVAL);
1152
1153 return get_mtd_device(NULL, minor / 2);
1154 }
1155
1156 /**
1157 * open_mtd_device - open MTD device by name, character device path, or number.
1158 * @mtd_dev: name, character device node path, or MTD device device number
1159 *
1160 * This function tries to open and MTD device described by @mtd_dev string,
1161 * which is first treated as ASCII MTD device number, and if it is not true, it
1162 * is treated as MTD device name, and if that is also not true, it is treated
1163 * as MTD character device node path. Returns MTD device description object in
1164 * case of success and a negative error code in case of failure.
1165 */
open_mtd_device(const char * mtd_dev)1166 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1167 {
1168 struct mtd_info *mtd;
1169 int mtd_num;
1170 char *endp;
1171
1172 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1173 if (*endp != '\0' || mtd_dev == endp) {
1174 /*
1175 * This does not look like an ASCII integer, probably this is
1176 * MTD device name.
1177 */
1178 mtd = get_mtd_device_nm(mtd_dev);
1179 if (PTR_ERR(mtd) == -ENODEV)
1180 /* Probably this is an MTD character device node path */
1181 mtd = open_mtd_by_chdev(mtd_dev);
1182 } else
1183 mtd = get_mtd_device(NULL, mtd_num);
1184
1185 return mtd;
1186 }
1187
ubi_init(void)1188 static int __init ubi_init(void)
1189 {
1190 int err, i, k;
1191
1192 /* Ensure that EC and VID headers have correct size */
1193 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1194 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1195
1196 if (mtd_devs > UBI_MAX_DEVICES) {
1197 pr_err("UBI error: too many MTD devices, maximum is %d\n",
1198 UBI_MAX_DEVICES);
1199 return -EINVAL;
1200 }
1201
1202 /* Create base sysfs directory and sysfs files */
1203 err = class_register(&ubi_class);
1204 if (err < 0)
1205 return err;
1206
1207 err = misc_register(&ubi_ctrl_cdev);
1208 if (err) {
1209 pr_err("UBI error: cannot register device\n");
1210 goto out;
1211 }
1212
1213 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1214 sizeof(struct ubi_wl_entry),
1215 0, 0, NULL);
1216 if (!ubi_wl_entry_slab) {
1217 err = -ENOMEM;
1218 goto out_dev_unreg;
1219 }
1220
1221 err = ubi_debugfs_init();
1222 if (err)
1223 goto out_slab;
1224
1225
1226 /* Attach MTD devices */
1227 for (i = 0; i < mtd_devs; i++) {
1228 struct mtd_dev_param *p = &mtd_dev_param[i];
1229 struct mtd_info *mtd;
1230
1231 cond_resched();
1232
1233 mtd = open_mtd_device(p->name);
1234 if (IS_ERR(mtd)) {
1235 err = PTR_ERR(mtd);
1236 pr_err("UBI error: cannot open mtd %s, error %d\n",
1237 p->name, err);
1238 /* See comment below re-ubi_is_module(). */
1239 if (ubi_is_module())
1240 goto out_detach;
1241 continue;
1242 }
1243
1244 mutex_lock(&ubi_devices_mutex);
1245 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1246 p->vid_hdr_offs, p->max_beb_per1024);
1247 mutex_unlock(&ubi_devices_mutex);
1248 if (err < 0) {
1249 pr_err("UBI error: cannot attach mtd%d\n",
1250 mtd->index);
1251 put_mtd_device(mtd);
1252
1253 /*
1254 * Originally UBI stopped initializing on any error.
1255 * However, later on it was found out that this
1256 * behavior is not very good when UBI is compiled into
1257 * the kernel and the MTD devices to attach are passed
1258 * through the command line. Indeed, UBI failure
1259 * stopped whole boot sequence.
1260 *
1261 * To fix this, we changed the behavior for the
1262 * non-module case, but preserved the old behavior for
1263 * the module case, just for compatibility. This is a
1264 * little inconsistent, though.
1265 */
1266 if (ubi_is_module())
1267 goto out_detach;
1268 }
1269 }
1270
1271 err = ubiblock_init();
1272 if (err) {
1273 pr_err("UBI error: block: cannot initialize, error %d\n", err);
1274
1275 /* See comment above re-ubi_is_module(). */
1276 if (ubi_is_module())
1277 goto out_detach;
1278 }
1279
1280 return 0;
1281
1282 out_detach:
1283 for (k = 0; k < i; k++)
1284 if (ubi_devices[k]) {
1285 mutex_lock(&ubi_devices_mutex);
1286 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1287 mutex_unlock(&ubi_devices_mutex);
1288 }
1289 ubi_debugfs_exit();
1290 out_slab:
1291 kmem_cache_destroy(ubi_wl_entry_slab);
1292 out_dev_unreg:
1293 misc_deregister(&ubi_ctrl_cdev);
1294 out:
1295 class_unregister(&ubi_class);
1296 pr_err("UBI error: cannot initialize UBI, error %d\n", err);
1297 return err;
1298 }
1299 late_initcall(ubi_init);
1300
ubi_exit(void)1301 static void __exit ubi_exit(void)
1302 {
1303 int i;
1304
1305 ubiblock_exit();
1306
1307 for (i = 0; i < UBI_MAX_DEVICES; i++)
1308 if (ubi_devices[i]) {
1309 mutex_lock(&ubi_devices_mutex);
1310 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1311 mutex_unlock(&ubi_devices_mutex);
1312 }
1313 ubi_debugfs_exit();
1314 kmem_cache_destroy(ubi_wl_entry_slab);
1315 misc_deregister(&ubi_ctrl_cdev);
1316 class_unregister(&ubi_class);
1317 }
1318 module_exit(ubi_exit);
1319
1320 /**
1321 * bytes_str_to_int - convert a number of bytes string into an integer.
1322 * @str: the string to convert
1323 *
1324 * This function returns positive resulting integer in case of success and a
1325 * negative error code in case of failure.
1326 */
bytes_str_to_int(const char * str)1327 static int bytes_str_to_int(const char *str)
1328 {
1329 char *endp;
1330 unsigned long result;
1331
1332 result = simple_strtoul(str, &endp, 0);
1333 if (str == endp || result >= INT_MAX) {
1334 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1335 return -EINVAL;
1336 }
1337
1338 switch (*endp) {
1339 case 'G':
1340 result *= 1024;
1341 fallthrough;
1342 case 'M':
1343 result *= 1024;
1344 fallthrough;
1345 case 'K':
1346 result *= 1024;
1347 if (endp[1] == 'i' && endp[2] == 'B')
1348 endp += 2;
1349 case '\0':
1350 break;
1351 default:
1352 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1353 return -EINVAL;
1354 }
1355
1356 return result;
1357 }
1358
1359 /**
1360 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1361 * @val: the parameter value to parse
1362 * @kp: not used
1363 *
1364 * This function returns zero in case of success and a negative error code in
1365 * case of error.
1366 */
ubi_mtd_param_parse(const char * val,const struct kernel_param * kp)1367 static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
1368 {
1369 int i, len;
1370 struct mtd_dev_param *p;
1371 char buf[MTD_PARAM_LEN_MAX];
1372 char *pbuf = &buf[0];
1373 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1374
1375 if (!val)
1376 return -EINVAL;
1377
1378 if (mtd_devs == UBI_MAX_DEVICES) {
1379 pr_err("UBI error: too many parameters, max. is %d\n",
1380 UBI_MAX_DEVICES);
1381 return -EINVAL;
1382 }
1383
1384 len = strnlen(val, MTD_PARAM_LEN_MAX);
1385 if (len == MTD_PARAM_LEN_MAX) {
1386 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1387 val, MTD_PARAM_LEN_MAX);
1388 return -EINVAL;
1389 }
1390
1391 if (len == 0) {
1392 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1393 return 0;
1394 }
1395
1396 strcpy(buf, val);
1397
1398 /* Get rid of the final newline */
1399 if (buf[len - 1] == '\n')
1400 buf[len - 1] = '\0';
1401
1402 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1403 tokens[i] = strsep(&pbuf, ",");
1404
1405 if (pbuf) {
1406 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1407 return -EINVAL;
1408 }
1409
1410 p = &mtd_dev_param[mtd_devs];
1411 strcpy(&p->name[0], tokens[0]);
1412
1413 token = tokens[1];
1414 if (token) {
1415 p->vid_hdr_offs = bytes_str_to_int(token);
1416
1417 if (p->vid_hdr_offs < 0)
1418 return p->vid_hdr_offs;
1419 }
1420
1421 token = tokens[2];
1422 if (token) {
1423 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1424
1425 if (err) {
1426 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1427 token);
1428 return -EINVAL;
1429 }
1430 }
1431
1432 token = tokens[3];
1433 if (token) {
1434 int err = kstrtoint(token, 10, &p->ubi_num);
1435
1436 if (err) {
1437 pr_err("UBI error: bad value for ubi_num parameter: %s",
1438 token);
1439 return -EINVAL;
1440 }
1441 } else
1442 p->ubi_num = UBI_DEV_NUM_AUTO;
1443
1444 mtd_devs += 1;
1445 return 0;
1446 }
1447
1448 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1449 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1450 "Multiple \"mtd\" parameters may be specified.\n"
1451 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1452 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1453 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1454 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1455 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1456 "\n"
1457 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1458 "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"
1459 "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"
1460 "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"
1461 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1462 #ifdef CONFIG_MTD_UBI_FASTMAP
1463 module_param(fm_autoconvert, bool, 0644);
1464 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1465 module_param(fm_debug, bool, 0);
1466 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1467 #endif
1468 MODULE_VERSION(__stringify(UBI_VERSION));
1469 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1470 MODULE_AUTHOR("Artem Bityutskiy");
1471 MODULE_LICENSE("GPL");
1472