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