2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2007
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 * Author: Artem Bityutskiy (Битюцкий Артём),
24 * This file includes UBI initialization and building of UBI devices.
26 * When UBI is initialized, it attaches all the MTD devices specified as the
27 * module load parameters or the kernel boot parameters. If MTD devices were
28 * specified, UBI does not attach any MTD device, but it is possible to do
29 * later using the "UBI control device".
32 #include <linux/err.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/stringify.h>
36 #include <linux/namei.h>
37 #include <linux/stat.h>
38 #include <linux/miscdevice.h>
39 #include <linux/mtd/partitions.h>
40 #include <linux/log2.h>
41 #include <linux/kthread.h>
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/major.h>
47 /* Maximum length of the 'mtd=' parameter */
48 #define MTD_PARAM_LEN_MAX 64
50 /* Maximum number of comma-separated items in the 'mtd=' parameter */
51 #define MTD_PARAM_MAX_COUNT 4
53 /* Maximum value for the number of bad PEBs per 1024 PEBs */
54 #define MAX_MTD_UBI_BEB_LIMIT 768
56 #ifdef CONFIG_MTD_UBI_MODULE
57 #define ubi_is_module() 1
59 #define ubi_is_module() 0
63 * struct mtd_dev_param - MTD device parameter description data structure.
64 * @name: MTD character device node path, MTD device name, or MTD device number
66 * @vid_hdr_offs: VID header offset
67 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
69 struct mtd_dev_param {
70 char name[MTD_PARAM_LEN_MAX];
76 /* Numbers of elements set in the @mtd_dev_param array */
79 /* MTD devices specification parameters */
80 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
81 #ifdef CONFIG_MTD_UBI_FASTMAP
82 /* UBI module parameter to enable fastmap automatically on non-fastmap images */
83 static bool fm_autoconvert;
87 /* Slab cache for wear-leveling entries */
88 struct kmem_cache *ubi_wl_entry_slab;
90 /* UBI control character device */
91 static struct miscdevice ubi_ctrl_cdev = {
92 .minor = MISC_DYNAMIC_MINOR,
94 .fops = &ubi_ctrl_cdev_operations,
97 /* All UBI devices in system */
98 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
100 /* Serializes UBI devices creations and removals */
101 DEFINE_MUTEX(ubi_devices_mutex);
103 /* Protects @ubi_devices and @ubi->ref_count */
104 static DEFINE_SPINLOCK(ubi_devices_lock);
106 /* "Show" method for files in '/<sysfs>/class/ubi/' */
107 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
108 static ssize_t version_show(struct class *class, struct class_attribute *attr,
111 return sprintf(buf, "%d\n", UBI_VERSION);
113 static CLASS_ATTR_RO(version);
115 static struct attribute *ubi_class_attrs[] = {
116 &class_attr_version.attr,
119 ATTRIBUTE_GROUPS(ubi_class);
121 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
122 struct class ubi_class = {
123 .name = UBI_NAME_STR,
124 .owner = THIS_MODULE,
125 .class_groups = ubi_class_groups,
128 static ssize_t dev_attribute_show(struct device *dev,
129 struct device_attribute *attr, char *buf);
131 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
132 static struct device_attribute dev_eraseblock_size =
133 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
134 static struct device_attribute dev_avail_eraseblocks =
135 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
136 static struct device_attribute dev_total_eraseblocks =
137 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
138 static struct device_attribute dev_volumes_count =
139 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
140 static struct device_attribute dev_max_ec =
141 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
142 static struct device_attribute dev_reserved_for_bad =
143 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
144 static struct device_attribute dev_bad_peb_count =
145 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
146 static struct device_attribute dev_max_vol_count =
147 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
148 static struct device_attribute dev_min_io_size =
149 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
150 static struct device_attribute dev_bgt_enabled =
151 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
152 static struct device_attribute dev_mtd_num =
153 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
154 static struct device_attribute dev_ro_mode =
155 __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
158 * ubi_volume_notify - send a volume change notification.
159 * @ubi: UBI device description object
160 * @vol: volume description object of the changed volume
161 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
163 * This is a helper function which notifies all subscribers about a volume
164 * change event (creation, removal, re-sizing, re-naming, updating). Returns
165 * zero in case of success and a negative error code in case of failure.
167 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
170 struct ubi_notification nt;
172 ubi_do_get_device_info(ubi, &nt.di);
173 ubi_do_get_volume_info(ubi, vol, &nt.vi);
176 case UBI_VOLUME_ADDED:
177 case UBI_VOLUME_REMOVED:
178 case UBI_VOLUME_RESIZED:
179 case UBI_VOLUME_RENAMED:
180 ret = ubi_update_fastmap(ubi);
182 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
185 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
189 * ubi_notify_all - send a notification to all volumes.
190 * @ubi: UBI device description object
191 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
192 * @nb: the notifier to call
194 * This function walks all volumes of UBI device @ubi and sends the @ntype
195 * notification for each volume. If @nb is %NULL, then all registered notifiers
196 * are called, otherwise only the @nb notifier is called. Returns the number of
197 * sent notifications.
199 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
201 struct ubi_notification nt;
204 ubi_do_get_device_info(ubi, &nt.di);
206 mutex_lock(&ubi->device_mutex);
207 for (i = 0; i < ubi->vtbl_slots; i++) {
209 * Since the @ubi->device is locked, and we are not going to
210 * change @ubi->volumes, we do not have to lock
211 * @ubi->volumes_lock.
213 if (!ubi->volumes[i])
216 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
218 nb->notifier_call(nb, ntype, &nt);
220 blocking_notifier_call_chain(&ubi_notifiers, ntype,
224 mutex_unlock(&ubi->device_mutex);
230 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
231 * @nb: the notifier to call
233 * This function walks all UBI devices and volumes and sends the
234 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
235 * registered notifiers are called, otherwise only the @nb notifier is called.
236 * Returns the number of sent notifications.
238 int ubi_enumerate_volumes(struct notifier_block *nb)
243 * Since the @ubi_devices_mutex is locked, and we are not going to
244 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
246 for (i = 0; i < UBI_MAX_DEVICES; i++) {
247 struct ubi_device *ubi = ubi_devices[i];
251 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
258 * ubi_get_device - get UBI device.
259 * @ubi_num: UBI device number
261 * This function returns UBI device description object for UBI device number
262 * @ubi_num, or %NULL if the device does not exist. This function increases the
263 * device reference count to prevent removal of the device. In other words, the
264 * device cannot be removed if its reference count is not zero.
266 struct ubi_device *ubi_get_device(int ubi_num)
268 struct ubi_device *ubi;
270 spin_lock(&ubi_devices_lock);
271 ubi = ubi_devices[ubi_num];
273 ubi_assert(ubi->ref_count >= 0);
275 get_device(&ubi->dev);
277 spin_unlock(&ubi_devices_lock);
283 * ubi_put_device - drop an UBI device reference.
284 * @ubi: UBI device description object
286 void ubi_put_device(struct ubi_device *ubi)
288 spin_lock(&ubi_devices_lock);
290 put_device(&ubi->dev);
291 spin_unlock(&ubi_devices_lock);
295 * ubi_get_by_major - get UBI device by character device major number.
296 * @major: major number
298 * This function is similar to 'ubi_get_device()', but it searches the device
299 * by its major number.
301 struct ubi_device *ubi_get_by_major(int major)
304 struct ubi_device *ubi;
306 spin_lock(&ubi_devices_lock);
307 for (i = 0; i < UBI_MAX_DEVICES; i++) {
308 ubi = ubi_devices[i];
309 if (ubi && MAJOR(ubi->cdev.dev) == major) {
310 ubi_assert(ubi->ref_count >= 0);
312 get_device(&ubi->dev);
313 spin_unlock(&ubi_devices_lock);
317 spin_unlock(&ubi_devices_lock);
323 * ubi_major2num - get UBI device number by character device major number.
324 * @major: major number
326 * This function searches UBI device number object by its major number. If UBI
327 * device was not found, this function returns -ENODEV, otherwise the UBI device
328 * number is returned.
330 int ubi_major2num(int major)
332 int i, ubi_num = -ENODEV;
334 spin_lock(&ubi_devices_lock);
335 for (i = 0; i < UBI_MAX_DEVICES; i++) {
336 struct ubi_device *ubi = ubi_devices[i];
338 if (ubi && MAJOR(ubi->cdev.dev) == major) {
339 ubi_num = ubi->ubi_num;
343 spin_unlock(&ubi_devices_lock);
348 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
349 static ssize_t dev_attribute_show(struct device *dev,
350 struct device_attribute *attr, char *buf)
353 struct ubi_device *ubi;
356 * The below code looks weird, but it actually makes sense. We get the
357 * UBI device reference from the contained 'struct ubi_device'. But it
358 * is unclear if the device was removed or not yet. Indeed, if the
359 * device was removed before we increased its reference count,
360 * 'ubi_get_device()' will return -ENODEV and we fail.
362 * Remember, 'struct ubi_device' is freed in the release function, so
363 * we still can use 'ubi->ubi_num'.
365 ubi = container_of(dev, struct ubi_device, dev);
366 ubi = ubi_get_device(ubi->ubi_num);
370 if (attr == &dev_eraseblock_size)
371 ret = sprintf(buf, "%d\n", ubi->leb_size);
372 else if (attr == &dev_avail_eraseblocks)
373 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
374 else if (attr == &dev_total_eraseblocks)
375 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
376 else if (attr == &dev_volumes_count)
377 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
378 else if (attr == &dev_max_ec)
379 ret = sprintf(buf, "%d\n", ubi->max_ec);
380 else if (attr == &dev_reserved_for_bad)
381 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
382 else if (attr == &dev_bad_peb_count)
383 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
384 else if (attr == &dev_max_vol_count)
385 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
386 else if (attr == &dev_min_io_size)
387 ret = sprintf(buf, "%d\n", ubi->min_io_size);
388 else if (attr == &dev_bgt_enabled)
389 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
390 else if (attr == &dev_mtd_num)
391 ret = sprintf(buf, "%d\n", ubi->mtd->index);
392 else if (attr == &dev_ro_mode)
393 ret = sprintf(buf, "%d\n", ubi->ro_mode);
401 static struct attribute *ubi_dev_attrs[] = {
402 &dev_eraseblock_size.attr,
403 &dev_avail_eraseblocks.attr,
404 &dev_total_eraseblocks.attr,
405 &dev_volumes_count.attr,
407 &dev_reserved_for_bad.attr,
408 &dev_bad_peb_count.attr,
409 &dev_max_vol_count.attr,
410 &dev_min_io_size.attr,
411 &dev_bgt_enabled.attr,
416 ATTRIBUTE_GROUPS(ubi_dev);
418 static void dev_release(struct device *dev)
420 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
426 * kill_volumes - destroy all user volumes.
427 * @ubi: UBI device description object
429 static void kill_volumes(struct ubi_device *ubi)
433 for (i = 0; i < ubi->vtbl_slots; i++)
435 ubi_free_volume(ubi, ubi->volumes[i]);
439 * uif_init - initialize user interfaces for an UBI device.
440 * @ubi: UBI device description object
442 * This function initializes various user interfaces for an UBI device. If the
443 * initialization fails at an early stage, this function frees all the
444 * resources it allocated, returns an error.
446 * This function returns zero in case of success and a negative error code in
449 static int uif_init(struct ubi_device *ubi)
454 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
457 * Major numbers for the UBI character devices are allocated
458 * dynamically. Major numbers of volume character devices are
459 * equivalent to ones of the corresponding UBI character device. Minor
460 * numbers of UBI character devices are 0, while minor numbers of
461 * volume character devices start from 1. Thus, we allocate one major
462 * number and ubi->vtbl_slots + 1 minor numbers.
464 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
466 ubi_err(ubi, "cannot register UBI character devices");
472 ubi_assert(MINOR(dev) == 0);
473 cdev_init(&ubi->cdev, &ubi_cdev_operations);
474 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
475 ubi->cdev.owner = THIS_MODULE;
477 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
478 err = cdev_device_add(&ubi->cdev, &ubi->dev);
482 for (i = 0; i < ubi->vtbl_slots; i++)
483 if (ubi->volumes[i]) {
484 err = ubi_add_volume(ubi, ubi->volumes[i]);
486 ubi_err(ubi, "cannot add volume %d", i);
495 cdev_device_del(&ubi->cdev, &ubi->dev);
497 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
498 ubi_err(ubi, "cannot initialize UBI %s, error %d",
504 * uif_close - close user interfaces for an UBI device.
505 * @ubi: UBI device description object
507 * Note, since this function un-registers UBI volume device objects (@vol->dev),
508 * the memory allocated voe the volumes is freed as well (in the release
511 static void uif_close(struct ubi_device *ubi)
514 cdev_device_del(&ubi->cdev, &ubi->dev);
515 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
519 * ubi_free_internal_volumes - free internal volumes.
520 * @ubi: UBI device description object
522 void ubi_free_internal_volumes(struct ubi_device *ubi)
526 for (i = ubi->vtbl_slots;
527 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
528 ubi_eba_replace_table(ubi->volumes[i], NULL);
529 kfree(ubi->volumes[i]);
533 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
535 int limit, device_pebs;
536 uint64_t device_size;
538 if (!max_beb_per1024)
542 * Here we are using size of the entire flash chip and
543 * not just the MTD partition size because the maximum
544 * number of bad eraseblocks is a percentage of the
545 * whole device and bad eraseblocks are not fairly
546 * distributed over the flash chip. So the worst case
547 * is that all the bad eraseblocks of the chip are in
548 * the MTD partition we are attaching (ubi->mtd).
550 device_size = mtd_get_device_size(ubi->mtd);
551 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
552 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
555 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
562 * io_init - initialize I/O sub-system for a given UBI device.
563 * @ubi: UBI device description object
564 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
566 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
568 * o EC header is always at offset zero - this cannot be changed;
569 * o VID header starts just after the EC header at the closest address
570 * aligned to @io->hdrs_min_io_size;
571 * o data starts just after the VID header at the closest address aligned to
574 * This function returns zero in case of success and a negative error code in
577 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
579 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
580 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
582 if (ubi->mtd->numeraseregions != 0) {
584 * Some flashes have several erase regions. Different regions
585 * may have different eraseblock size and other
586 * characteristics. It looks like mostly multi-region flashes
587 * have one "main" region and one or more small regions to
588 * store boot loader code or boot parameters or whatever. I
589 * guess we should just pick the largest region. But this is
592 ubi_err(ubi, "multiple regions, not implemented");
596 if (ubi->vid_hdr_offset < 0)
600 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
601 * physical eraseblocks maximum.
604 ubi->peb_size = ubi->mtd->erasesize;
605 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
606 ubi->flash_size = ubi->mtd->size;
608 if (mtd_can_have_bb(ubi->mtd)) {
609 ubi->bad_allowed = 1;
610 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
613 if (ubi->mtd->type == MTD_NORFLASH) {
614 ubi_assert(ubi->mtd->writesize == 1);
618 ubi->min_io_size = ubi->mtd->writesize;
619 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
622 * Make sure minimal I/O unit is power of 2. Note, there is no
623 * fundamental reason for this assumption. It is just an optimization
624 * which allows us to avoid costly division operations.
626 if (!is_power_of_2(ubi->min_io_size)) {
627 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
632 ubi_assert(ubi->hdrs_min_io_size > 0);
633 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
634 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
636 ubi->max_write_size = ubi->mtd->writebufsize;
638 * Maximum write size has to be greater or equivalent to min. I/O
639 * size, and be multiple of min. I/O size.
641 if (ubi->max_write_size < ubi->min_io_size ||
642 ubi->max_write_size % ubi->min_io_size ||
643 !is_power_of_2(ubi->max_write_size)) {
644 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
645 ubi->max_write_size, ubi->min_io_size);
649 /* Calculate default aligned sizes of EC and VID headers */
650 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
651 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
653 dbg_gen("min_io_size %d", ubi->min_io_size);
654 dbg_gen("max_write_size %d", ubi->max_write_size);
655 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
656 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
657 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
659 if (ubi->vid_hdr_offset == 0)
661 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
664 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
665 ~(ubi->hdrs_min_io_size - 1);
666 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
667 ubi->vid_hdr_aloffset;
670 /* Similar for the data offset */
671 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
672 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
674 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
675 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
676 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
677 dbg_gen("leb_start %d", ubi->leb_start);
679 /* The shift must be aligned to 32-bit boundary */
680 if (ubi->vid_hdr_shift % 4) {
681 ubi_err(ubi, "unaligned VID header shift %d",
687 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
688 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
689 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
690 ubi->leb_start & (ubi->min_io_size - 1)) {
691 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
692 ubi->vid_hdr_offset, ubi->leb_start);
697 * Set maximum amount of physical erroneous eraseblocks to be 10%.
698 * Erroneous PEB are those which have read errors.
700 ubi->max_erroneous = ubi->peb_count / 10;
701 if (ubi->max_erroneous < 16)
702 ubi->max_erroneous = 16;
703 dbg_gen("max_erroneous %d", ubi->max_erroneous);
706 * It may happen that EC and VID headers are situated in one minimal
707 * I/O unit. In this case we can only accept this UBI image in
710 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
711 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
715 ubi->leb_size = ubi->peb_size - ubi->leb_start;
717 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
718 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
724 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
725 * unfortunately, MTD does not provide this information. We should loop
726 * over all physical eraseblocks and invoke mtd->block_is_bad() for
727 * each physical eraseblock. So, we leave @ubi->bad_peb_count
728 * uninitialized so far.
735 * autoresize - re-size the volume which has the "auto-resize" flag set.
736 * @ubi: UBI device description object
737 * @vol_id: ID of the volume to re-size
739 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
740 * the volume table to the largest possible size. See comments in ubi-header.h
741 * for more description of the flag. Returns zero in case of success and a
742 * negative error code in case of failure.
744 static int autoresize(struct ubi_device *ubi, int vol_id)
746 struct ubi_volume_desc desc;
747 struct ubi_volume *vol = ubi->volumes[vol_id];
748 int err, old_reserved_pebs = vol->reserved_pebs;
751 ubi_warn(ubi, "skip auto-resize because of R/O mode");
756 * Clear the auto-resize flag in the volume in-memory copy of the
757 * volume table, and 'ubi_resize_volume()' will propagate this change
760 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
762 if (ubi->avail_pebs == 0) {
763 struct ubi_vtbl_record vtbl_rec;
766 * No available PEBs to re-size the volume, clear the flag on
769 vtbl_rec = ubi->vtbl[vol_id];
770 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
772 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
776 err = ubi_resize_volume(&desc,
777 old_reserved_pebs + ubi->avail_pebs);
779 ubi_err(ubi, "cannot auto-resize volume %d",
786 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
787 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
792 * ubi_attach_mtd_dev - attach an MTD device.
793 * @mtd: MTD device description object
794 * @ubi_num: number to assign to the new UBI device
795 * @vid_hdr_offset: VID header offset
796 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
798 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
799 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
800 * which case this function finds a vacant device number and assigns it
801 * automatically. Returns the new UBI device number in case of success and a
802 * negative error code in case of failure.
804 * Note, the invocations of this function has to be serialized by the
805 * @ubi_devices_mutex.
807 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
808 int vid_hdr_offset, int max_beb_per1024)
810 struct ubi_device *ubi;
813 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
816 if (!max_beb_per1024)
817 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
820 * Check if we already have the same MTD device attached.
822 * Note, this function assumes that UBI devices creations and deletions
823 * are serialized, so it does not take the &ubi_devices_lock.
825 for (i = 0; i < UBI_MAX_DEVICES; i++) {
826 ubi = ubi_devices[i];
827 if (ubi && mtd->index == ubi->mtd->index) {
828 pr_err("ubi: mtd%d is already attached to ubi%d",
835 * Make sure this MTD device is not emulated on top of an UBI volume
836 * already. Well, generally this recursion works fine, but there are
837 * different problems like the UBI module takes a reference to itself
838 * by attaching (and thus, opening) the emulated MTD device. This
839 * results in inability to unload the module. And in general it makes
840 * no sense to attach emulated MTD devices, so we prohibit this.
842 if (mtd->type == MTD_UBIVOLUME) {
843 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI",
848 if (ubi_num == UBI_DEV_NUM_AUTO) {
849 /* Search for an empty slot in the @ubi_devices array */
850 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
851 if (!ubi_devices[ubi_num])
853 if (ubi_num == UBI_MAX_DEVICES) {
854 pr_err("ubi: only %d UBI devices may be created",
859 if (ubi_num >= UBI_MAX_DEVICES)
862 /* Make sure ubi_num is not busy */
863 if (ubi_devices[ubi_num]) {
864 pr_err("ubi: ubi%i already exists", ubi_num);
869 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
873 device_initialize(&ubi->dev);
874 ubi->dev.release = dev_release;
875 ubi->dev.class = &ubi_class;
876 ubi->dev.groups = ubi_dev_groups;
879 ubi->ubi_num = ubi_num;
880 ubi->vid_hdr_offset = vid_hdr_offset;
881 ubi->autoresize_vol_id = -1;
883 #ifdef CONFIG_MTD_UBI_FASTMAP
884 ubi->fm_pool.used = ubi->fm_pool.size = 0;
885 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
888 * fm_pool.max_size is 5% of the total number of PEBs but it's also
889 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
891 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
892 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
893 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
894 UBI_FM_MIN_POOL_SIZE);
896 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
897 ubi->fm_disabled = !fm_autoconvert;
899 ubi_enable_dbg_chk_fastmap(ubi);
901 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
902 <= UBI_FM_MAX_START) {
903 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
905 ubi->fm_disabled = 1;
908 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
909 ubi_msg(ubi, "default fastmap WL pool size: %d",
910 ubi->fm_wl_pool.max_size);
912 ubi->fm_disabled = 1;
914 mutex_init(&ubi->buf_mutex);
915 mutex_init(&ubi->ckvol_mutex);
916 mutex_init(&ubi->device_mutex);
917 spin_lock_init(&ubi->volumes_lock);
918 init_rwsem(&ubi->fm_protect);
919 init_rwsem(&ubi->fm_eba_sem);
921 ubi_msg(ubi, "attaching mtd%d", mtd->index);
923 err = io_init(ubi, max_beb_per1024);
928 ubi->peb_buf = vmalloc(ubi->peb_size);
932 #ifdef CONFIG_MTD_UBI_FASTMAP
933 ubi->fm_size = ubi_calc_fm_size(ubi);
934 ubi->fm_buf = vzalloc(ubi->fm_size);
938 err = ubi_attach(ubi, 0);
940 ubi_err(ubi, "failed to attach mtd%d, error %d",
945 if (ubi->autoresize_vol_id != -1) {
946 err = autoresize(ubi, ubi->autoresize_vol_id);
951 /* Make device "available" before it becomes accessible via sysfs */
952 ubi_devices[ubi_num] = ubi;
958 err = ubi_debugfs_init_dev(ubi);
962 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
963 if (IS_ERR(ubi->bgt_thread)) {
964 err = PTR_ERR(ubi->bgt_thread);
965 ubi_err(ubi, "cannot spawn \"%s\", error %d",
970 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
971 mtd->index, mtd->name, ubi->flash_size >> 20);
972 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
973 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
974 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
975 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
976 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
977 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
978 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
979 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
980 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
981 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
983 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
984 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
986 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
987 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
990 * The below lock makes sure we do not race with 'ubi_thread()' which
991 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
993 spin_lock(&ubi->wl_lock);
994 ubi->thread_enabled = 1;
995 wake_up_process(ubi->bgt_thread);
996 spin_unlock(&ubi->wl_lock);
998 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1002 ubi_debugfs_exit_dev(ubi);
1006 ubi_devices[ubi_num] = NULL;
1008 ubi_free_internal_volumes(ubi);
1011 vfree(ubi->peb_buf);
1013 put_device(&ubi->dev);
1018 * ubi_detach_mtd_dev - detach an MTD device.
1019 * @ubi_num: UBI device number to detach from
1020 * @anyway: detach MTD even if device reference count is not zero
1022 * This function destroys an UBI device number @ubi_num and detaches the
1023 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1024 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1027 * Note, the invocations of this function has to be serialized by the
1028 * @ubi_devices_mutex.
1030 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1032 struct ubi_device *ubi;
1034 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1037 ubi = ubi_get_device(ubi_num);
1041 spin_lock(&ubi_devices_lock);
1042 put_device(&ubi->dev);
1043 ubi->ref_count -= 1;
1044 if (ubi->ref_count) {
1046 spin_unlock(&ubi_devices_lock);
1049 /* This may only happen if there is a bug */
1050 ubi_err(ubi, "%s reference count %d, destroy anyway",
1051 ubi->ubi_name, ubi->ref_count);
1053 ubi_devices[ubi_num] = NULL;
1054 spin_unlock(&ubi_devices_lock);
1056 ubi_assert(ubi_num == ubi->ubi_num);
1057 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1058 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1059 #ifdef CONFIG_MTD_UBI_FASTMAP
1060 /* If we don't write a new fastmap at detach time we lose all
1061 * EC updates that have been made since the last written fastmap.
1062 * In case of fastmap debugging we omit the update to simulate an
1063 * unclean shutdown. */
1064 if (!ubi_dbg_chk_fastmap(ubi))
1065 ubi_update_fastmap(ubi);
1068 * Before freeing anything, we have to stop the background thread to
1069 * prevent it from doing anything on this device while we are freeing.
1071 if (ubi->bgt_thread)
1072 kthread_stop(ubi->bgt_thread);
1074 ubi_debugfs_exit_dev(ubi);
1078 ubi_free_internal_volumes(ubi);
1080 put_mtd_device(ubi->mtd);
1081 vfree(ubi->peb_buf);
1083 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1084 put_device(&ubi->dev);
1089 * open_mtd_by_chdev - open an MTD device by its character device node path.
1090 * @mtd_dev: MTD character device node path
1092 * This helper function opens an MTD device by its character node device path.
1093 * Returns MTD device description object in case of success and a negative
1094 * error code in case of failure.
1096 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1102 /* Probably this is an MTD character device node path */
1103 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1105 return ERR_PTR(err);
1107 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1110 return ERR_PTR(err);
1112 /* MTD device number is defined by the major / minor numbers */
1113 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1114 return ERR_PTR(-EINVAL);
1116 minor = MINOR(stat.rdev);
1120 * Just do not think the "/dev/mtdrX" devices support is need,
1121 * so do not support them to avoid doing extra work.
1123 return ERR_PTR(-EINVAL);
1125 return get_mtd_device(NULL, minor / 2);
1129 * open_mtd_device - open MTD device by name, character device path, or number.
1130 * @mtd_dev: name, character device node path, or MTD device device number
1132 * This function tries to open and MTD device described by @mtd_dev string,
1133 * which is first treated as ASCII MTD device number, and if it is not true, it
1134 * is treated as MTD device name, and if that is also not true, it is treated
1135 * as MTD character device node path. Returns MTD device description object in
1136 * case of success and a negative error code in case of failure.
1138 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1140 struct mtd_info *mtd;
1144 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1145 if (*endp != '\0' || mtd_dev == endp) {
1147 * This does not look like an ASCII integer, probably this is
1150 mtd = get_mtd_device_nm(mtd_dev);
1151 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1152 /* Probably this is an MTD character device node path */
1153 mtd = open_mtd_by_chdev(mtd_dev);
1155 mtd = get_mtd_device(NULL, mtd_num);
1160 static int __init ubi_init(void)
1164 /* Ensure that EC and VID headers have correct size */
1165 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1166 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1168 if (mtd_devs > UBI_MAX_DEVICES) {
1169 pr_err("UBI error: too many MTD devices, maximum is %d",
1174 /* Create base sysfs directory and sysfs files */
1175 err = class_register(&ubi_class);
1179 err = misc_register(&ubi_ctrl_cdev);
1181 pr_err("UBI error: cannot register device");
1185 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1186 sizeof(struct ubi_wl_entry),
1188 if (!ubi_wl_entry_slab) {
1193 err = ubi_debugfs_init();
1198 /* Attach MTD devices */
1199 for (i = 0; i < mtd_devs; i++) {
1200 struct mtd_dev_param *p = &mtd_dev_param[i];
1201 struct mtd_info *mtd;
1205 mtd = open_mtd_device(p->name);
1208 pr_err("UBI error: cannot open mtd %s, error %d",
1210 /* See comment below re-ubi_is_module(). */
1211 if (ubi_is_module())
1216 mutex_lock(&ubi_devices_mutex);
1217 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1218 p->vid_hdr_offs, p->max_beb_per1024);
1219 mutex_unlock(&ubi_devices_mutex);
1221 pr_err("UBI error: cannot attach mtd%d",
1223 put_mtd_device(mtd);
1226 * Originally UBI stopped initializing on any error.
1227 * However, later on it was found out that this
1228 * behavior is not very good when UBI is compiled into
1229 * the kernel and the MTD devices to attach are passed
1230 * through the command line. Indeed, UBI failure
1231 * stopped whole boot sequence.
1233 * To fix this, we changed the behavior for the
1234 * non-module case, but preserved the old behavior for
1235 * the module case, just for compatibility. This is a
1236 * little inconsistent, though.
1238 if (ubi_is_module())
1243 err = ubiblock_init();
1245 pr_err("UBI error: block: cannot initialize, error %d", err);
1247 /* See comment above re-ubi_is_module(). */
1248 if (ubi_is_module())
1255 for (k = 0; k < i; k++)
1256 if (ubi_devices[k]) {
1257 mutex_lock(&ubi_devices_mutex);
1258 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1259 mutex_unlock(&ubi_devices_mutex);
1263 kmem_cache_destroy(ubi_wl_entry_slab);
1265 misc_deregister(&ubi_ctrl_cdev);
1267 class_unregister(&ubi_class);
1268 pr_err("UBI error: cannot initialize UBI, error %d", err);
1271 late_initcall(ubi_init);
1273 static void __exit ubi_exit(void)
1279 for (i = 0; i < UBI_MAX_DEVICES; i++)
1280 if (ubi_devices[i]) {
1281 mutex_lock(&ubi_devices_mutex);
1282 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1283 mutex_unlock(&ubi_devices_mutex);
1286 kmem_cache_destroy(ubi_wl_entry_slab);
1287 misc_deregister(&ubi_ctrl_cdev);
1288 class_unregister(&ubi_class);
1290 module_exit(ubi_exit);
1293 * bytes_str_to_int - convert a number of bytes string into an integer.
1294 * @str: the string to convert
1296 * This function returns positive resulting integer in case of success and a
1297 * negative error code in case of failure.
1299 static int bytes_str_to_int(const char *str)
1302 unsigned long result;
1304 result = simple_strtoul(str, &endp, 0);
1305 if (str == endp || result >= INT_MAX) {
1306 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1317 if (endp[1] == 'i' && endp[2] == 'B')
1322 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1330 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1331 * @val: the parameter value to parse
1334 * This function returns zero in case of success and a negative error code in
1337 static int ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1340 struct mtd_dev_param *p;
1341 char buf[MTD_PARAM_LEN_MAX];
1342 char *pbuf = &buf[0];
1343 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1348 if (mtd_devs == UBI_MAX_DEVICES) {
1349 pr_err("UBI error: too many parameters, max. is %d\n",
1354 len = strnlen(val, MTD_PARAM_LEN_MAX);
1355 if (len == MTD_PARAM_LEN_MAX) {
1356 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1357 val, MTD_PARAM_LEN_MAX);
1362 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1368 /* Get rid of the final newline */
1369 if (buf[len - 1] == '\n')
1370 buf[len - 1] = '\0';
1372 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1373 tokens[i] = strsep(&pbuf, ",");
1376 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1380 p = &mtd_dev_param[mtd_devs];
1381 strcpy(&p->name[0], tokens[0]);
1385 p->vid_hdr_offs = bytes_str_to_int(token);
1387 if (p->vid_hdr_offs < 0)
1388 return p->vid_hdr_offs;
1393 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1396 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1404 int err = kstrtoint(token, 10, &p->ubi_num);
1407 pr_err("UBI error: bad value for ubi_num parameter: %s",
1412 p->ubi_num = UBI_DEV_NUM_AUTO;
1418 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1419 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1420 "Multiple \"mtd\" parameters may be specified.\n"
1421 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1422 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1423 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1424 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1425 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1427 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1428 "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"
1429 "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"
1430 "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"
1431 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1432 #ifdef CONFIG_MTD_UBI_FASTMAP
1433 module_param(fm_autoconvert, bool, 0644);
1434 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1435 module_param(fm_debug, bool, 0);
1436 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1438 MODULE_VERSION(__stringify(UBI_VERSION));
1439 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1440 MODULE_AUTHOR("Artem Bityutskiy");
1441 MODULE_LICENSE("GPL");