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 */
77 static int __initdata mtd_devs;
79 /* MTD devices specification parameters */
80 static struct mtd_dev_param __initdata 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 static ssize_t ubi_version_show(struct class *class,
108 struct class_attribute *attr, char *buf)
110 return sprintf(buf, "%d\n", UBI_VERSION);
113 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
114 static struct class_attribute ubi_class_attrs[] = {
115 __ATTR(version, S_IRUGO, ubi_version_show, NULL),
119 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
120 struct class ubi_class = {
121 .name = UBI_NAME_STR,
122 .owner = THIS_MODULE,
123 .class_attrs = ubi_class_attrs,
126 static ssize_t dev_attribute_show(struct device *dev,
127 struct device_attribute *attr, char *buf);
129 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
130 static struct device_attribute dev_eraseblock_size =
131 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
132 static struct device_attribute dev_avail_eraseblocks =
133 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
134 static struct device_attribute dev_total_eraseblocks =
135 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
136 static struct device_attribute dev_volumes_count =
137 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
138 static struct device_attribute dev_max_ec =
139 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
140 static struct device_attribute dev_reserved_for_bad =
141 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
142 static struct device_attribute dev_bad_peb_count =
143 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
144 static struct device_attribute dev_max_vol_count =
145 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
146 static struct device_attribute dev_min_io_size =
147 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
148 static struct device_attribute dev_bgt_enabled =
149 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
150 static struct device_attribute dev_mtd_num =
151 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
152 static struct device_attribute dev_ro_mode =
153 __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
156 * ubi_volume_notify - send a volume change notification.
157 * @ubi: UBI device description object
158 * @vol: volume description object of the changed volume
159 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
161 * This is a helper function which notifies all subscribers about a volume
162 * change event (creation, removal, re-sizing, re-naming, updating). Returns
163 * zero in case of success and a negative error code in case of failure.
165 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
168 struct ubi_notification nt;
170 ubi_do_get_device_info(ubi, &nt.di);
171 ubi_do_get_volume_info(ubi, vol, &nt.vi);
174 case UBI_VOLUME_ADDED:
175 case UBI_VOLUME_REMOVED:
176 case UBI_VOLUME_RESIZED:
177 case UBI_VOLUME_RENAMED:
178 ret = ubi_update_fastmap(ubi);
180 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
183 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
187 * ubi_notify_all - send a notification to all volumes.
188 * @ubi: UBI device description object
189 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
190 * @nb: the notifier to call
192 * This function walks all volumes of UBI device @ubi and sends the @ntype
193 * notification for each volume. If @nb is %NULL, then all registered notifiers
194 * are called, otherwise only the @nb notifier is called. Returns the number of
195 * sent notifications.
197 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
199 struct ubi_notification nt;
202 ubi_do_get_device_info(ubi, &nt.di);
204 mutex_lock(&ubi->device_mutex);
205 for (i = 0; i < ubi->vtbl_slots; i++) {
207 * Since the @ubi->device is locked, and we are not going to
208 * change @ubi->volumes, we do not have to lock
209 * @ubi->volumes_lock.
211 if (!ubi->volumes[i])
214 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
216 nb->notifier_call(nb, ntype, &nt);
218 blocking_notifier_call_chain(&ubi_notifiers, ntype,
222 mutex_unlock(&ubi->device_mutex);
228 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
229 * @nb: the notifier to call
231 * This function walks all UBI devices and volumes and sends the
232 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
233 * registered notifiers are called, otherwise only the @nb notifier is called.
234 * Returns the number of sent notifications.
236 int ubi_enumerate_volumes(struct notifier_block *nb)
241 * Since the @ubi_devices_mutex is locked, and we are not going to
242 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
244 for (i = 0; i < UBI_MAX_DEVICES; i++) {
245 struct ubi_device *ubi = ubi_devices[i];
249 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
256 * ubi_get_device - get UBI device.
257 * @ubi_num: UBI device number
259 * This function returns UBI device description object for UBI device number
260 * @ubi_num, or %NULL if the device does not exist. This function increases the
261 * device reference count to prevent removal of the device. In other words, the
262 * device cannot be removed if its reference count is not zero.
264 struct ubi_device *ubi_get_device(int ubi_num)
266 struct ubi_device *ubi;
268 spin_lock(&ubi_devices_lock);
269 ubi = ubi_devices[ubi_num];
271 ubi_assert(ubi->ref_count >= 0);
273 get_device(&ubi->dev);
275 spin_unlock(&ubi_devices_lock);
281 * ubi_put_device - drop an UBI device reference.
282 * @ubi: UBI device description object
284 void ubi_put_device(struct ubi_device *ubi)
286 spin_lock(&ubi_devices_lock);
288 put_device(&ubi->dev);
289 spin_unlock(&ubi_devices_lock);
293 * ubi_get_by_major - get UBI device by character device major number.
294 * @major: major number
296 * This function is similar to 'ubi_get_device()', but it searches the device
297 * by its major number.
299 struct ubi_device *ubi_get_by_major(int major)
302 struct ubi_device *ubi;
304 spin_lock(&ubi_devices_lock);
305 for (i = 0; i < UBI_MAX_DEVICES; i++) {
306 ubi = ubi_devices[i];
307 if (ubi && MAJOR(ubi->cdev.dev) == major) {
308 ubi_assert(ubi->ref_count >= 0);
310 get_device(&ubi->dev);
311 spin_unlock(&ubi_devices_lock);
315 spin_unlock(&ubi_devices_lock);
321 * ubi_major2num - get UBI device number by character device major number.
322 * @major: major number
324 * This function searches UBI device number object by its major number. If UBI
325 * device was not found, this function returns -ENODEV, otherwise the UBI device
326 * number is returned.
328 int ubi_major2num(int major)
330 int i, ubi_num = -ENODEV;
332 spin_lock(&ubi_devices_lock);
333 for (i = 0; i < UBI_MAX_DEVICES; i++) {
334 struct ubi_device *ubi = ubi_devices[i];
336 if (ubi && MAJOR(ubi->cdev.dev) == major) {
337 ubi_num = ubi->ubi_num;
341 spin_unlock(&ubi_devices_lock);
346 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
347 static ssize_t dev_attribute_show(struct device *dev,
348 struct device_attribute *attr, char *buf)
351 struct ubi_device *ubi;
354 * The below code looks weird, but it actually makes sense. We get the
355 * UBI device reference from the contained 'struct ubi_device'. But it
356 * is unclear if the device was removed or not yet. Indeed, if the
357 * device was removed before we increased its reference count,
358 * 'ubi_get_device()' will return -ENODEV and we fail.
360 * Remember, 'struct ubi_device' is freed in the release function, so
361 * we still can use 'ubi->ubi_num'.
363 ubi = container_of(dev, struct ubi_device, dev);
364 ubi = ubi_get_device(ubi->ubi_num);
368 if (attr == &dev_eraseblock_size)
369 ret = sprintf(buf, "%d\n", ubi->leb_size);
370 else if (attr == &dev_avail_eraseblocks)
371 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
372 else if (attr == &dev_total_eraseblocks)
373 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
374 else if (attr == &dev_volumes_count)
375 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
376 else if (attr == &dev_max_ec)
377 ret = sprintf(buf, "%d\n", ubi->max_ec);
378 else if (attr == &dev_reserved_for_bad)
379 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
380 else if (attr == &dev_bad_peb_count)
381 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
382 else if (attr == &dev_max_vol_count)
383 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
384 else if (attr == &dev_min_io_size)
385 ret = sprintf(buf, "%d\n", ubi->min_io_size);
386 else if (attr == &dev_bgt_enabled)
387 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
388 else if (attr == &dev_mtd_num)
389 ret = sprintf(buf, "%d\n", ubi->mtd->index);
390 else if (attr == &dev_ro_mode)
391 ret = sprintf(buf, "%d\n", ubi->ro_mode);
399 static struct attribute *ubi_dev_attrs[] = {
400 &dev_eraseblock_size.attr,
401 &dev_avail_eraseblocks.attr,
402 &dev_total_eraseblocks.attr,
403 &dev_volumes_count.attr,
405 &dev_reserved_for_bad.attr,
406 &dev_bad_peb_count.attr,
407 &dev_max_vol_count.attr,
408 &dev_min_io_size.attr,
409 &dev_bgt_enabled.attr,
414 ATTRIBUTE_GROUPS(ubi_dev);
416 static void dev_release(struct device *dev)
418 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
424 * kill_volumes - destroy all user volumes.
425 * @ubi: UBI device description object
427 static void kill_volumes(struct ubi_device *ubi)
431 for (i = 0; i < ubi->vtbl_slots; i++)
433 ubi_free_volume(ubi, ubi->volumes[i]);
437 * uif_init - initialize user interfaces for an UBI device.
438 * @ubi: UBI device description object
440 * This function initializes various user interfaces for an UBI device. If the
441 * initialization fails at an early stage, this function frees all the
442 * resources it allocated, returns an error.
444 * This function returns zero in case of success and a negative error code in
447 static int uif_init(struct ubi_device *ubi)
452 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
455 * Major numbers for the UBI character devices are allocated
456 * dynamically. Major numbers of volume character devices are
457 * equivalent to ones of the corresponding UBI character device. Minor
458 * numbers of UBI character devices are 0, while minor numbers of
459 * volume character devices start from 1. Thus, we allocate one major
460 * number and ubi->vtbl_slots + 1 minor numbers.
462 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
464 ubi_err(ubi, "cannot register UBI character devices");
470 ubi_assert(MINOR(dev) == 0);
471 cdev_init(&ubi->cdev, &ubi_cdev_operations);
472 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
473 ubi->cdev.owner = THIS_MODULE;
475 dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
476 err = cdev_device_add(&ubi->cdev, &ubi->dev);
480 for (i = 0; i < ubi->vtbl_slots; i++)
481 if (ubi->volumes[i]) {
482 err = ubi_add_volume(ubi, ubi->volumes[i]);
484 ubi_err(ubi, "cannot add volume %d", i);
493 cdev_device_del(&ubi->cdev, &ubi->dev);
495 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
496 ubi_err(ubi, "cannot initialize UBI %s, error %d",
502 * uif_close - close user interfaces for an UBI device.
503 * @ubi: UBI device description object
505 * Note, since this function un-registers UBI volume device objects (@vol->dev),
506 * the memory allocated voe the volumes is freed as well (in the release
509 static void uif_close(struct ubi_device *ubi)
512 cdev_device_del(&ubi->cdev, &ubi->dev);
513 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
517 * ubi_free_internal_volumes - free internal volumes.
518 * @ubi: UBI device description object
520 void ubi_free_internal_volumes(struct ubi_device *ubi)
524 for (i = ubi->vtbl_slots;
525 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
526 ubi_eba_replace_table(ubi->volumes[i], NULL);
527 kfree(ubi->volumes[i]);
531 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
533 int limit, device_pebs;
534 uint64_t device_size;
536 if (!max_beb_per1024)
540 * Here we are using size of the entire flash chip and
541 * not just the MTD partition size because the maximum
542 * number of bad eraseblocks is a percentage of the
543 * whole device and bad eraseblocks are not fairly
544 * distributed over the flash chip. So the worst case
545 * is that all the bad eraseblocks of the chip are in
546 * the MTD partition we are attaching (ubi->mtd).
548 device_size = mtd_get_device_size(ubi->mtd);
549 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
550 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
553 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
560 * io_init - initialize I/O sub-system for a given UBI device.
561 * @ubi: UBI device description object
562 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
564 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
566 * o EC header is always at offset zero - this cannot be changed;
567 * o VID header starts just after the EC header at the closest address
568 * aligned to @io->hdrs_min_io_size;
569 * o data starts just after the VID header at the closest address aligned to
572 * This function returns zero in case of success and a negative error code in
575 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
577 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
578 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
580 if (ubi->mtd->numeraseregions != 0) {
582 * Some flashes have several erase regions. Different regions
583 * may have different eraseblock size and other
584 * characteristics. It looks like mostly multi-region flashes
585 * have one "main" region and one or more small regions to
586 * store boot loader code or boot parameters or whatever. I
587 * guess we should just pick the largest region. But this is
590 ubi_err(ubi, "multiple regions, not implemented");
594 if (ubi->vid_hdr_offset < 0)
598 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
599 * physical eraseblocks maximum.
602 ubi->peb_size = ubi->mtd->erasesize;
603 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
604 ubi->flash_size = ubi->mtd->size;
606 if (mtd_can_have_bb(ubi->mtd)) {
607 ubi->bad_allowed = 1;
608 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
611 if (ubi->mtd->type == MTD_NORFLASH) {
612 ubi_assert(ubi->mtd->writesize == 1);
616 ubi->min_io_size = ubi->mtd->writesize;
617 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
620 * Make sure minimal I/O unit is power of 2. Note, there is no
621 * fundamental reason for this assumption. It is just an optimization
622 * which allows us to avoid costly division operations.
624 if (!is_power_of_2(ubi->min_io_size)) {
625 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
630 ubi_assert(ubi->hdrs_min_io_size > 0);
631 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
632 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
634 ubi->max_write_size = ubi->mtd->writebufsize;
636 * Maximum write size has to be greater or equivalent to min. I/O
637 * size, and be multiple of min. I/O size.
639 if (ubi->max_write_size < ubi->min_io_size ||
640 ubi->max_write_size % ubi->min_io_size ||
641 !is_power_of_2(ubi->max_write_size)) {
642 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
643 ubi->max_write_size, ubi->min_io_size);
647 /* Calculate default aligned sizes of EC and VID headers */
648 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
649 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
651 dbg_gen("min_io_size %d", ubi->min_io_size);
652 dbg_gen("max_write_size %d", ubi->max_write_size);
653 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
654 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
655 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
657 if (ubi->vid_hdr_offset == 0)
659 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
662 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
663 ~(ubi->hdrs_min_io_size - 1);
664 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
665 ubi->vid_hdr_aloffset;
668 /* Similar for the data offset */
669 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
670 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
672 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
673 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
674 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
675 dbg_gen("leb_start %d", ubi->leb_start);
677 /* The shift must be aligned to 32-bit boundary */
678 if (ubi->vid_hdr_shift % 4) {
679 ubi_err(ubi, "unaligned VID header shift %d",
685 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
686 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
687 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
688 ubi->leb_start & (ubi->min_io_size - 1)) {
689 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
690 ubi->vid_hdr_offset, ubi->leb_start);
695 * Set maximum amount of physical erroneous eraseblocks to be 10%.
696 * Erroneous PEB are those which have read errors.
698 ubi->max_erroneous = ubi->peb_count / 10;
699 if (ubi->max_erroneous < 16)
700 ubi->max_erroneous = 16;
701 dbg_gen("max_erroneous %d", ubi->max_erroneous);
704 * It may happen that EC and VID headers are situated in one minimal
705 * I/O unit. In this case we can only accept this UBI image in
708 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
709 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
713 ubi->leb_size = ubi->peb_size - ubi->leb_start;
715 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
716 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
722 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
723 * unfortunately, MTD does not provide this information. We should loop
724 * over all physical eraseblocks and invoke mtd->block_is_bad() for
725 * each physical eraseblock. So, we leave @ubi->bad_peb_count
726 * uninitialized so far.
733 * autoresize - re-size the volume which has the "auto-resize" flag set.
734 * @ubi: UBI device description object
735 * @vol_id: ID of the volume to re-size
737 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
738 * the volume table to the largest possible size. See comments in ubi-header.h
739 * for more description of the flag. Returns zero in case of success and a
740 * negative error code in case of failure.
742 static int autoresize(struct ubi_device *ubi, int vol_id)
744 struct ubi_volume_desc desc;
745 struct ubi_volume *vol = ubi->volumes[vol_id];
746 int err, old_reserved_pebs = vol->reserved_pebs;
749 ubi_warn(ubi, "skip auto-resize because of R/O mode");
754 * Clear the auto-resize flag in the volume in-memory copy of the
755 * volume table, and 'ubi_resize_volume()' will propagate this change
758 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
760 if (ubi->avail_pebs == 0) {
761 struct ubi_vtbl_record vtbl_rec;
764 * No available PEBs to re-size the volume, clear the flag on
767 vtbl_rec = ubi->vtbl[vol_id];
768 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
770 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
774 err = ubi_resize_volume(&desc,
775 old_reserved_pebs + ubi->avail_pebs);
777 ubi_err(ubi, "cannot auto-resize volume %d",
784 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
785 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
790 * ubi_attach_mtd_dev - attach an MTD device.
791 * @mtd: MTD device description object
792 * @ubi_num: number to assign to the new UBI device
793 * @vid_hdr_offset: VID header offset
794 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
796 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
797 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
798 * which case this function finds a vacant device number and assigns it
799 * automatically. Returns the new UBI device number in case of success and a
800 * negative error code in case of failure.
802 * Note, the invocations of this function has to be serialized by the
803 * @ubi_devices_mutex.
805 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
806 int vid_hdr_offset, int max_beb_per1024)
808 struct ubi_device *ubi;
811 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
814 if (!max_beb_per1024)
815 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
818 * Check if we already have the same MTD device attached.
820 * Note, this function assumes that UBI devices creations and deletions
821 * are serialized, so it does not take the &ubi_devices_lock.
823 for (i = 0; i < UBI_MAX_DEVICES; i++) {
824 ubi = ubi_devices[i];
825 if (ubi && mtd->index == ubi->mtd->index) {
826 pr_err("ubi: mtd%d is already attached to ubi%d",
833 * Make sure this MTD device is not emulated on top of an UBI volume
834 * already. Well, generally this recursion works fine, but there are
835 * different problems like the UBI module takes a reference to itself
836 * by attaching (and thus, opening) the emulated MTD device. This
837 * results in inability to unload the module. And in general it makes
838 * no sense to attach emulated MTD devices, so we prohibit this.
840 if (mtd->type == MTD_UBIVOLUME) {
841 pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI",
846 if (ubi_num == UBI_DEV_NUM_AUTO) {
847 /* Search for an empty slot in the @ubi_devices array */
848 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
849 if (!ubi_devices[ubi_num])
851 if (ubi_num == UBI_MAX_DEVICES) {
852 pr_err("ubi: only %d UBI devices may be created",
857 if (ubi_num >= UBI_MAX_DEVICES)
860 /* Make sure ubi_num is not busy */
861 if (ubi_devices[ubi_num]) {
862 pr_err("ubi: ubi%i already exists", ubi_num);
867 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
871 device_initialize(&ubi->dev);
872 ubi->dev.release = dev_release;
873 ubi->dev.class = &ubi_class;
874 ubi->dev.groups = ubi_dev_groups;
877 ubi->ubi_num = ubi_num;
878 ubi->vid_hdr_offset = vid_hdr_offset;
879 ubi->autoresize_vol_id = -1;
881 #ifdef CONFIG_MTD_UBI_FASTMAP
882 ubi->fm_pool.used = ubi->fm_pool.size = 0;
883 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
886 * fm_pool.max_size is 5% of the total number of PEBs but it's also
887 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
889 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
890 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
891 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
892 UBI_FM_MIN_POOL_SIZE);
894 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
895 ubi->fm_disabled = !fm_autoconvert;
897 ubi_enable_dbg_chk_fastmap(ubi);
899 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
900 <= UBI_FM_MAX_START) {
901 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
903 ubi->fm_disabled = 1;
906 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
907 ubi_msg(ubi, "default fastmap WL pool size: %d",
908 ubi->fm_wl_pool.max_size);
910 ubi->fm_disabled = 1;
912 mutex_init(&ubi->buf_mutex);
913 mutex_init(&ubi->ckvol_mutex);
914 mutex_init(&ubi->device_mutex);
915 spin_lock_init(&ubi->volumes_lock);
916 init_rwsem(&ubi->fm_protect);
917 init_rwsem(&ubi->fm_eba_sem);
919 ubi_msg(ubi, "attaching mtd%d", mtd->index);
921 err = io_init(ubi, max_beb_per1024);
926 ubi->peb_buf = vmalloc(ubi->peb_size);
930 #ifdef CONFIG_MTD_UBI_FASTMAP
931 ubi->fm_size = ubi_calc_fm_size(ubi);
932 ubi->fm_buf = vzalloc(ubi->fm_size);
936 err = ubi_attach(ubi, 0);
938 ubi_err(ubi, "failed to attach mtd%d, error %d",
943 if (ubi->autoresize_vol_id != -1) {
944 err = autoresize(ubi, ubi->autoresize_vol_id);
949 /* Make device "available" before it becomes accessible via sysfs */
950 ubi_devices[ubi_num] = ubi;
956 err = ubi_debugfs_init_dev(ubi);
960 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
961 if (IS_ERR(ubi->bgt_thread)) {
962 err = PTR_ERR(ubi->bgt_thread);
963 ubi_err(ubi, "cannot spawn \"%s\", error %d",
968 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
969 mtd->index, mtd->name, ubi->flash_size >> 20);
970 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
971 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
972 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
973 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
974 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
975 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
976 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
977 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
978 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
979 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
981 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
982 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
984 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
985 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
988 * The below lock makes sure we do not race with 'ubi_thread()' which
989 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
991 spin_lock(&ubi->wl_lock);
992 ubi->thread_enabled = 1;
993 wake_up_process(ubi->bgt_thread);
994 spin_unlock(&ubi->wl_lock);
996 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1000 ubi_debugfs_exit_dev(ubi);
1004 ubi_devices[ubi_num] = NULL;
1006 ubi_free_internal_volumes(ubi);
1009 vfree(ubi->peb_buf);
1011 put_device(&ubi->dev);
1016 * ubi_detach_mtd_dev - detach an MTD device.
1017 * @ubi_num: UBI device number to detach from
1018 * @anyway: detach MTD even if device reference count is not zero
1020 * This function destroys an UBI device number @ubi_num and detaches the
1021 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1022 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1025 * Note, the invocations of this function has to be serialized by the
1026 * @ubi_devices_mutex.
1028 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1030 struct ubi_device *ubi;
1032 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1035 ubi = ubi_get_device(ubi_num);
1039 spin_lock(&ubi_devices_lock);
1040 put_device(&ubi->dev);
1041 ubi->ref_count -= 1;
1042 if (ubi->ref_count) {
1044 spin_unlock(&ubi_devices_lock);
1047 /* This may only happen if there is a bug */
1048 ubi_err(ubi, "%s reference count %d, destroy anyway",
1049 ubi->ubi_name, ubi->ref_count);
1051 ubi_devices[ubi_num] = NULL;
1052 spin_unlock(&ubi_devices_lock);
1054 ubi_assert(ubi_num == ubi->ubi_num);
1055 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1056 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1057 #ifdef CONFIG_MTD_UBI_FASTMAP
1058 /* If we don't write a new fastmap at detach time we lose all
1059 * EC updates that have been made since the last written fastmap.
1060 * In case of fastmap debugging we omit the update to simulate an
1061 * unclean shutdown. */
1062 if (!ubi_dbg_chk_fastmap(ubi))
1063 ubi_update_fastmap(ubi);
1066 * Before freeing anything, we have to stop the background thread to
1067 * prevent it from doing anything on this device while we are freeing.
1069 if (ubi->bgt_thread)
1070 kthread_stop(ubi->bgt_thread);
1072 ubi_debugfs_exit_dev(ubi);
1076 ubi_free_internal_volumes(ubi);
1078 put_mtd_device(ubi->mtd);
1079 vfree(ubi->peb_buf);
1081 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1082 put_device(&ubi->dev);
1087 * open_mtd_by_chdev - open an MTD device by its character device node path.
1088 * @mtd_dev: MTD character device node path
1090 * This helper function opens an MTD device by its character node device path.
1091 * Returns MTD device description object in case of success and a negative
1092 * error code in case of failure.
1094 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1100 /* Probably this is an MTD character device node path */
1101 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1103 return ERR_PTR(err);
1105 err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1108 return ERR_PTR(err);
1110 /* MTD device number is defined by the major / minor numbers */
1111 if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1112 return ERR_PTR(-EINVAL);
1114 minor = MINOR(stat.rdev);
1118 * Just do not think the "/dev/mtdrX" devices support is need,
1119 * so do not support them to avoid doing extra work.
1121 return ERR_PTR(-EINVAL);
1123 return get_mtd_device(NULL, minor / 2);
1127 * open_mtd_device - open MTD device by name, character device path, or number.
1128 * @mtd_dev: name, character device node path, or MTD device device number
1130 * This function tries to open and MTD device described by @mtd_dev string,
1131 * which is first treated as ASCII MTD device number, and if it is not true, it
1132 * is treated as MTD device name, and if that is also not true, it is treated
1133 * as MTD character device node path. Returns MTD device description object in
1134 * case of success and a negative error code in case of failure.
1136 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1138 struct mtd_info *mtd;
1142 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1143 if (*endp != '\0' || mtd_dev == endp) {
1145 * This does not look like an ASCII integer, probably this is
1148 mtd = get_mtd_device_nm(mtd_dev);
1149 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1150 /* Probably this is an MTD character device node path */
1151 mtd = open_mtd_by_chdev(mtd_dev);
1153 mtd = get_mtd_device(NULL, mtd_num);
1158 static int __init ubi_init(void)
1162 /* Ensure that EC and VID headers have correct size */
1163 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1164 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1166 if (mtd_devs > UBI_MAX_DEVICES) {
1167 pr_err("UBI error: too many MTD devices, maximum is %d",
1172 /* Create base sysfs directory and sysfs files */
1173 err = class_register(&ubi_class);
1177 err = misc_register(&ubi_ctrl_cdev);
1179 pr_err("UBI error: cannot register device");
1183 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1184 sizeof(struct ubi_wl_entry),
1186 if (!ubi_wl_entry_slab) {
1191 err = ubi_debugfs_init();
1196 /* Attach MTD devices */
1197 for (i = 0; i < mtd_devs; i++) {
1198 struct mtd_dev_param *p = &mtd_dev_param[i];
1199 struct mtd_info *mtd;
1203 mtd = open_mtd_device(p->name);
1206 pr_err("UBI error: cannot open mtd %s, error %d",
1208 /* See comment below re-ubi_is_module(). */
1209 if (ubi_is_module())
1214 mutex_lock(&ubi_devices_mutex);
1215 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1216 p->vid_hdr_offs, p->max_beb_per1024);
1217 mutex_unlock(&ubi_devices_mutex);
1219 pr_err("UBI error: cannot attach mtd%d",
1221 put_mtd_device(mtd);
1224 * Originally UBI stopped initializing on any error.
1225 * However, later on it was found out that this
1226 * behavior is not very good when UBI is compiled into
1227 * the kernel and the MTD devices to attach are passed
1228 * through the command line. Indeed, UBI failure
1229 * stopped whole boot sequence.
1231 * To fix this, we changed the behavior for the
1232 * non-module case, but preserved the old behavior for
1233 * the module case, just for compatibility. This is a
1234 * little inconsistent, though.
1236 if (ubi_is_module())
1241 err = ubiblock_init();
1243 pr_err("UBI error: block: cannot initialize, error %d", err);
1245 /* See comment above re-ubi_is_module(). */
1246 if (ubi_is_module())
1253 for (k = 0; k < i; k++)
1254 if (ubi_devices[k]) {
1255 mutex_lock(&ubi_devices_mutex);
1256 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1257 mutex_unlock(&ubi_devices_mutex);
1261 kmem_cache_destroy(ubi_wl_entry_slab);
1263 misc_deregister(&ubi_ctrl_cdev);
1265 class_unregister(&ubi_class);
1266 pr_err("UBI error: cannot initialize UBI, error %d", err);
1269 late_initcall(ubi_init);
1271 static void __exit ubi_exit(void)
1277 for (i = 0; i < UBI_MAX_DEVICES; i++)
1278 if (ubi_devices[i]) {
1279 mutex_lock(&ubi_devices_mutex);
1280 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1281 mutex_unlock(&ubi_devices_mutex);
1284 kmem_cache_destroy(ubi_wl_entry_slab);
1285 misc_deregister(&ubi_ctrl_cdev);
1286 class_unregister(&ubi_class);
1288 module_exit(ubi_exit);
1291 * bytes_str_to_int - convert a number of bytes string into an integer.
1292 * @str: the string to convert
1294 * This function returns positive resulting integer in case of success and a
1295 * negative error code in case of failure.
1297 static int __init bytes_str_to_int(const char *str)
1300 unsigned long result;
1302 result = simple_strtoul(str, &endp, 0);
1303 if (str == endp || result >= INT_MAX) {
1304 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1315 if (endp[1] == 'i' && endp[2] == 'B')
1320 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1328 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1329 * @val: the parameter value to parse
1332 * This function returns zero in case of success and a negative error code in
1335 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1338 struct mtd_dev_param *p;
1339 char buf[MTD_PARAM_LEN_MAX];
1340 char *pbuf = &buf[0];
1341 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1346 if (mtd_devs == UBI_MAX_DEVICES) {
1347 pr_err("UBI error: too many parameters, max. is %d\n",
1352 len = strnlen(val, MTD_PARAM_LEN_MAX);
1353 if (len == MTD_PARAM_LEN_MAX) {
1354 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1355 val, MTD_PARAM_LEN_MAX);
1360 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1366 /* Get rid of the final newline */
1367 if (buf[len - 1] == '\n')
1368 buf[len - 1] = '\0';
1370 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1371 tokens[i] = strsep(&pbuf, ",");
1374 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1378 p = &mtd_dev_param[mtd_devs];
1379 strcpy(&p->name[0], tokens[0]);
1383 p->vid_hdr_offs = bytes_str_to_int(token);
1385 if (p->vid_hdr_offs < 0)
1386 return p->vid_hdr_offs;
1391 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1394 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1402 int err = kstrtoint(token, 10, &p->ubi_num);
1405 pr_err("UBI error: bad value for ubi_num parameter: %s",
1410 p->ubi_num = UBI_DEV_NUM_AUTO;
1416 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1417 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1418 "Multiple \"mtd\" parameters may be specified.\n"
1419 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1420 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1421 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1422 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1423 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1425 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1426 "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"
1427 "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"
1428 "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"
1429 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1430 #ifdef CONFIG_MTD_UBI_FASTMAP
1431 module_param(fm_autoconvert, bool, 0644);
1432 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1433 module_param(fm_debug, bool, 0);
1434 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1436 MODULE_VERSION(__stringify(UBI_VERSION));
1437 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1438 MODULE_AUTHOR("Artem Bityutskiy");
1439 MODULE_LICENSE("GPL");