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);
154 * ubi_volume_notify - send a volume change notification.
155 * @ubi: UBI device description object
156 * @vol: volume description object of the changed volume
157 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
159 * This is a helper function which notifies all subscribers about a volume
160 * change event (creation, removal, re-sizing, re-naming, updating). Returns
161 * zero in case of success and a negative error code in case of failure.
163 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
166 struct ubi_notification nt;
168 ubi_do_get_device_info(ubi, &nt.di);
169 ubi_do_get_volume_info(ubi, vol, &nt.vi);
172 case UBI_VOLUME_ADDED:
173 case UBI_VOLUME_REMOVED:
174 case UBI_VOLUME_RESIZED:
175 case UBI_VOLUME_RENAMED:
176 ret = ubi_update_fastmap(ubi);
178 ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
181 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
185 * ubi_notify_all - send a notification to all volumes.
186 * @ubi: UBI device description object
187 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
188 * @nb: the notifier to call
190 * This function walks all volumes of UBI device @ubi and sends the @ntype
191 * notification for each volume. If @nb is %NULL, then all registered notifiers
192 * are called, otherwise only the @nb notifier is called. Returns the number of
193 * sent notifications.
195 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
197 struct ubi_notification nt;
200 ubi_do_get_device_info(ubi, &nt.di);
202 mutex_lock(&ubi->device_mutex);
203 for (i = 0; i < ubi->vtbl_slots; i++) {
205 * Since the @ubi->device is locked, and we are not going to
206 * change @ubi->volumes, we do not have to lock
207 * @ubi->volumes_lock.
209 if (!ubi->volumes[i])
212 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
214 nb->notifier_call(nb, ntype, &nt);
216 blocking_notifier_call_chain(&ubi_notifiers, ntype,
220 mutex_unlock(&ubi->device_mutex);
226 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
227 * @nb: the notifier to call
229 * This function walks all UBI devices and volumes and sends the
230 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
231 * registered notifiers are called, otherwise only the @nb notifier is called.
232 * Returns the number of sent notifications.
234 int ubi_enumerate_volumes(struct notifier_block *nb)
239 * Since the @ubi_devices_mutex is locked, and we are not going to
240 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
242 for (i = 0; i < UBI_MAX_DEVICES; i++) {
243 struct ubi_device *ubi = ubi_devices[i];
247 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
254 * ubi_get_device - get UBI device.
255 * @ubi_num: UBI device number
257 * This function returns UBI device description object for UBI device number
258 * @ubi_num, or %NULL if the device does not exist. This function increases the
259 * device reference count to prevent removal of the device. In other words, the
260 * device cannot be removed if its reference count is not zero.
262 struct ubi_device *ubi_get_device(int ubi_num)
264 struct ubi_device *ubi;
266 spin_lock(&ubi_devices_lock);
267 ubi = ubi_devices[ubi_num];
269 ubi_assert(ubi->ref_count >= 0);
271 get_device(&ubi->dev);
273 spin_unlock(&ubi_devices_lock);
279 * ubi_put_device - drop an UBI device reference.
280 * @ubi: UBI device description object
282 void ubi_put_device(struct ubi_device *ubi)
284 spin_lock(&ubi_devices_lock);
286 put_device(&ubi->dev);
287 spin_unlock(&ubi_devices_lock);
291 * ubi_get_by_major - get UBI device by character device major number.
292 * @major: major number
294 * This function is similar to 'ubi_get_device()', but it searches the device
295 * by its major number.
297 struct ubi_device *ubi_get_by_major(int major)
300 struct ubi_device *ubi;
302 spin_lock(&ubi_devices_lock);
303 for (i = 0; i < UBI_MAX_DEVICES; i++) {
304 ubi = ubi_devices[i];
305 if (ubi && MAJOR(ubi->cdev.dev) == major) {
306 ubi_assert(ubi->ref_count >= 0);
308 get_device(&ubi->dev);
309 spin_unlock(&ubi_devices_lock);
313 spin_unlock(&ubi_devices_lock);
319 * ubi_major2num - get UBI device number by character device major number.
320 * @major: major number
322 * This function searches UBI device number object by its major number. If UBI
323 * device was not found, this function returns -ENODEV, otherwise the UBI device
324 * number is returned.
326 int ubi_major2num(int major)
328 int i, ubi_num = -ENODEV;
330 spin_lock(&ubi_devices_lock);
331 for (i = 0; i < UBI_MAX_DEVICES; i++) {
332 struct ubi_device *ubi = ubi_devices[i];
334 if (ubi && MAJOR(ubi->cdev.dev) == major) {
335 ubi_num = ubi->ubi_num;
339 spin_unlock(&ubi_devices_lock);
344 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
345 static ssize_t dev_attribute_show(struct device *dev,
346 struct device_attribute *attr, char *buf)
349 struct ubi_device *ubi;
352 * The below code looks weird, but it actually makes sense. We get the
353 * UBI device reference from the contained 'struct ubi_device'. But it
354 * is unclear if the device was removed or not yet. Indeed, if the
355 * device was removed before we increased its reference count,
356 * 'ubi_get_device()' will return -ENODEV and we fail.
358 * Remember, 'struct ubi_device' is freed in the release function, so
359 * we still can use 'ubi->ubi_num'.
361 ubi = container_of(dev, struct ubi_device, dev);
362 ubi = ubi_get_device(ubi->ubi_num);
366 if (attr == &dev_eraseblock_size)
367 ret = sprintf(buf, "%d\n", ubi->leb_size);
368 else if (attr == &dev_avail_eraseblocks)
369 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
370 else if (attr == &dev_total_eraseblocks)
371 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
372 else if (attr == &dev_volumes_count)
373 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
374 else if (attr == &dev_max_ec)
375 ret = sprintf(buf, "%d\n", ubi->max_ec);
376 else if (attr == &dev_reserved_for_bad)
377 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
378 else if (attr == &dev_bad_peb_count)
379 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
380 else if (attr == &dev_max_vol_count)
381 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
382 else if (attr == &dev_min_io_size)
383 ret = sprintf(buf, "%d\n", ubi->min_io_size);
384 else if (attr == &dev_bgt_enabled)
385 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
386 else if (attr == &dev_mtd_num)
387 ret = sprintf(buf, "%d\n", ubi->mtd->index);
395 static struct attribute *ubi_dev_attrs[] = {
396 &dev_eraseblock_size.attr,
397 &dev_avail_eraseblocks.attr,
398 &dev_total_eraseblocks.attr,
399 &dev_volumes_count.attr,
401 &dev_reserved_for_bad.attr,
402 &dev_bad_peb_count.attr,
403 &dev_max_vol_count.attr,
404 &dev_min_io_size.attr,
405 &dev_bgt_enabled.attr,
409 ATTRIBUTE_GROUPS(ubi_dev);
411 static void dev_release(struct device *dev)
413 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
419 * ubi_sysfs_init - initialize sysfs for an UBI device.
420 * @ubi: UBI device description object
421 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
424 * This function returns zero in case of success and a negative error code in
427 static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
431 ubi->dev.release = dev_release;
432 ubi->dev.devt = ubi->cdev.dev;
433 ubi->dev.class = &ubi_class;
434 ubi->dev.groups = ubi_dev_groups;
435 dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
436 err = device_register(&ubi->dev);
445 * ubi_sysfs_close - close sysfs for an UBI device.
446 * @ubi: UBI device description object
448 static void ubi_sysfs_close(struct ubi_device *ubi)
450 device_unregister(&ubi->dev);
454 * kill_volumes - destroy all user volumes.
455 * @ubi: UBI device description object
457 static void kill_volumes(struct ubi_device *ubi)
461 for (i = 0; i < ubi->vtbl_slots; i++)
463 ubi_free_volume(ubi, ubi->volumes[i]);
467 * uif_init - initialize user interfaces for an UBI device.
468 * @ubi: UBI device description object
469 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
470 * taken, otherwise set to %0
472 * This function initializes various user interfaces for an UBI device. If the
473 * initialization fails at an early stage, this function frees all the
474 * resources it allocated, returns an error, and @ref is set to %0. However,
475 * if the initialization fails after the UBI device was registered in the
476 * driver core subsystem, this function takes a reference to @ubi->dev, because
477 * otherwise the release function ('dev_release()') would free whole @ubi
478 * object. The @ref argument is set to %1 in this case. The caller has to put
481 * This function returns zero in case of success and a negative error code in
484 static int uif_init(struct ubi_device *ubi, int *ref)
490 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
493 * Major numbers for the UBI character devices are allocated
494 * dynamically. Major numbers of volume character devices are
495 * equivalent to ones of the corresponding UBI character device. Minor
496 * numbers of UBI character devices are 0, while minor numbers of
497 * volume character devices start from 1. Thus, we allocate one major
498 * number and ubi->vtbl_slots + 1 minor numbers.
500 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
502 ubi_err(ubi, "cannot register UBI character devices");
506 ubi_assert(MINOR(dev) == 0);
507 cdev_init(&ubi->cdev, &ubi_cdev_operations);
508 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
509 ubi->cdev.owner = THIS_MODULE;
511 err = cdev_add(&ubi->cdev, dev, 1);
513 ubi_err(ubi, "cannot add character device");
517 err = ubi_sysfs_init(ubi, ref);
521 for (i = 0; i < ubi->vtbl_slots; i++)
522 if (ubi->volumes[i]) {
523 err = ubi_add_volume(ubi, ubi->volumes[i]);
525 ubi_err(ubi, "cannot add volume %d", i);
536 get_device(&ubi->dev);
537 ubi_sysfs_close(ubi);
538 cdev_del(&ubi->cdev);
540 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
541 ubi_err(ubi, "cannot initialize UBI %s, error %d",
547 * uif_close - close user interfaces for an UBI device.
548 * @ubi: UBI device description object
550 * Note, since this function un-registers UBI volume device objects (@vol->dev),
551 * the memory allocated voe the volumes is freed as well (in the release
554 static void uif_close(struct ubi_device *ubi)
557 ubi_sysfs_close(ubi);
558 cdev_del(&ubi->cdev);
559 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
563 * ubi_free_internal_volumes - free internal volumes.
564 * @ubi: UBI device description object
566 void ubi_free_internal_volumes(struct ubi_device *ubi)
570 for (i = ubi->vtbl_slots;
571 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
572 kfree(ubi->volumes[i]->eba_tbl);
573 kfree(ubi->volumes[i]);
577 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
579 int limit, device_pebs;
580 uint64_t device_size;
582 if (!max_beb_per1024)
586 * Here we are using size of the entire flash chip and
587 * not just the MTD partition size because the maximum
588 * number of bad eraseblocks is a percentage of the
589 * whole device and bad eraseblocks are not fairly
590 * distributed over the flash chip. So the worst case
591 * is that all the bad eraseblocks of the chip are in
592 * the MTD partition we are attaching (ubi->mtd).
594 device_size = mtd_get_device_size(ubi->mtd);
595 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
596 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
599 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
606 * io_init - initialize I/O sub-system for a given UBI device.
607 * @ubi: UBI device description object
608 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
610 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
612 * o EC header is always at offset zero - this cannot be changed;
613 * o VID header starts just after the EC header at the closest address
614 * aligned to @io->hdrs_min_io_size;
615 * o data starts just after the VID header at the closest address aligned to
618 * This function returns zero in case of success and a negative error code in
621 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
623 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
624 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
626 if (ubi->mtd->numeraseregions != 0) {
628 * Some flashes have several erase regions. Different regions
629 * may have different eraseblock size and other
630 * characteristics. It looks like mostly multi-region flashes
631 * have one "main" region and one or more small regions to
632 * store boot loader code or boot parameters or whatever. I
633 * guess we should just pick the largest region. But this is
636 ubi_err(ubi, "multiple regions, not implemented");
640 if (ubi->vid_hdr_offset < 0)
644 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
645 * physical eraseblocks maximum.
648 ubi->peb_size = ubi->mtd->erasesize;
649 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
650 ubi->flash_size = ubi->mtd->size;
652 if (mtd_can_have_bb(ubi->mtd)) {
653 ubi->bad_allowed = 1;
654 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
657 if (ubi->mtd->type == MTD_NORFLASH) {
658 ubi_assert(ubi->mtd->writesize == 1);
662 ubi->min_io_size = ubi->mtd->writesize;
663 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
666 * Make sure minimal I/O unit is power of 2. Note, there is no
667 * fundamental reason for this assumption. It is just an optimization
668 * which allows us to avoid costly division operations.
670 if (!is_power_of_2(ubi->min_io_size)) {
671 ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
676 ubi_assert(ubi->hdrs_min_io_size > 0);
677 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
678 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
680 ubi->max_write_size = ubi->mtd->writebufsize;
682 * Maximum write size has to be greater or equivalent to min. I/O
683 * size, and be multiple of min. I/O size.
685 if (ubi->max_write_size < ubi->min_io_size ||
686 ubi->max_write_size % ubi->min_io_size ||
687 !is_power_of_2(ubi->max_write_size)) {
688 ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
689 ubi->max_write_size, ubi->min_io_size);
693 /* Calculate default aligned sizes of EC and VID headers */
694 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
695 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
697 dbg_gen("min_io_size %d", ubi->min_io_size);
698 dbg_gen("max_write_size %d", ubi->max_write_size);
699 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
700 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
701 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
703 if (ubi->vid_hdr_offset == 0)
705 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
708 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
709 ~(ubi->hdrs_min_io_size - 1);
710 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
711 ubi->vid_hdr_aloffset;
714 /* Similar for the data offset */
715 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
716 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
718 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
719 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
720 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
721 dbg_gen("leb_start %d", ubi->leb_start);
723 /* The shift must be aligned to 32-bit boundary */
724 if (ubi->vid_hdr_shift % 4) {
725 ubi_err(ubi, "unaligned VID header shift %d",
731 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
732 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
733 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
734 ubi->leb_start & (ubi->min_io_size - 1)) {
735 ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
736 ubi->vid_hdr_offset, ubi->leb_start);
741 * Set maximum amount of physical erroneous eraseblocks to be 10%.
742 * Erroneous PEB are those which have read errors.
744 ubi->max_erroneous = ubi->peb_count / 10;
745 if (ubi->max_erroneous < 16)
746 ubi->max_erroneous = 16;
747 dbg_gen("max_erroneous %d", ubi->max_erroneous);
750 * It may happen that EC and VID headers are situated in one minimal
751 * I/O unit. In this case we can only accept this UBI image in
754 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
755 ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
759 ubi->leb_size = ubi->peb_size - ubi->leb_start;
761 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
762 ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
768 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
769 * unfortunately, MTD does not provide this information. We should loop
770 * over all physical eraseblocks and invoke mtd->block_is_bad() for
771 * each physical eraseblock. So, we leave @ubi->bad_peb_count
772 * uninitialized so far.
779 * autoresize - re-size the volume which has the "auto-resize" flag set.
780 * @ubi: UBI device description object
781 * @vol_id: ID of the volume to re-size
783 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
784 * the volume table to the largest possible size. See comments in ubi-header.h
785 * for more description of the flag. Returns zero in case of success and a
786 * negative error code in case of failure.
788 static int autoresize(struct ubi_device *ubi, int vol_id)
790 struct ubi_volume_desc desc;
791 struct ubi_volume *vol = ubi->volumes[vol_id];
792 int err, old_reserved_pebs = vol->reserved_pebs;
795 ubi_warn(ubi, "skip auto-resize because of R/O mode");
800 * Clear the auto-resize flag in the volume in-memory copy of the
801 * volume table, and 'ubi_resize_volume()' will propagate this change
804 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
806 if (ubi->avail_pebs == 0) {
807 struct ubi_vtbl_record vtbl_rec;
810 * No available PEBs to re-size the volume, clear the flag on
813 vtbl_rec = ubi->vtbl[vol_id];
814 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
816 ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
820 err = ubi_resize_volume(&desc,
821 old_reserved_pebs + ubi->avail_pebs);
823 ubi_err(ubi, "cannot auto-resize volume %d",
830 ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
831 vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
836 * ubi_attach_mtd_dev - attach an MTD device.
837 * @mtd: MTD device description object
838 * @ubi_num: number to assign to the new UBI device
839 * @vid_hdr_offset: VID header offset
840 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
842 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
843 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
844 * which case this function finds a vacant device number and assigns it
845 * automatically. Returns the new UBI device number in case of success and a
846 * negative error code in case of failure.
848 * Note, the invocations of this function has to be serialized by the
849 * @ubi_devices_mutex.
851 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
852 int vid_hdr_offset, int max_beb_per1024)
854 struct ubi_device *ubi;
857 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
860 if (!max_beb_per1024)
861 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
864 * Check if we already have the same MTD device attached.
866 * Note, this function assumes that UBI devices creations and deletions
867 * are serialized, so it does not take the &ubi_devices_lock.
869 for (i = 0; i < UBI_MAX_DEVICES; i++) {
870 ubi = ubi_devices[i];
871 if (ubi && mtd->index == ubi->mtd->index) {
872 ubi_err(ubi, "mtd%d is already attached to ubi%d",
879 * Make sure this MTD device is not emulated on top of an UBI volume
880 * already. Well, generally this recursion works fine, but there are
881 * different problems like the UBI module takes a reference to itself
882 * by attaching (and thus, opening) the emulated MTD device. This
883 * results in inability to unload the module. And in general it makes
884 * no sense to attach emulated MTD devices, so we prohibit this.
886 if (mtd->type == MTD_UBIVOLUME) {
887 ubi_err(ubi, "refuse attaching mtd%d - it is already emulated on top of UBI",
892 if (ubi_num == UBI_DEV_NUM_AUTO) {
893 /* Search for an empty slot in the @ubi_devices array */
894 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
895 if (!ubi_devices[ubi_num])
897 if (ubi_num == UBI_MAX_DEVICES) {
898 ubi_err(ubi, "only %d UBI devices may be created",
903 if (ubi_num >= UBI_MAX_DEVICES)
906 /* Make sure ubi_num is not busy */
907 if (ubi_devices[ubi_num]) {
908 ubi_err(ubi, "already exists");
913 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
918 ubi->ubi_num = ubi_num;
919 ubi->vid_hdr_offset = vid_hdr_offset;
920 ubi->autoresize_vol_id = -1;
922 #ifdef CONFIG_MTD_UBI_FASTMAP
923 ubi->fm_pool.used = ubi->fm_pool.size = 0;
924 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
927 * fm_pool.max_size is 5% of the total number of PEBs but it's also
928 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
930 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
931 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
932 ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
933 UBI_FM_MIN_POOL_SIZE);
935 ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
936 ubi->fm_disabled = !fm_autoconvert;
938 ubi_enable_dbg_chk_fastmap(ubi);
940 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
941 <= UBI_FM_MAX_START) {
942 ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
944 ubi->fm_disabled = 1;
947 ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
948 ubi_msg(ubi, "default fastmap WL pool size: %d",
949 ubi->fm_wl_pool.max_size);
951 ubi->fm_disabled = 1;
953 mutex_init(&ubi->buf_mutex);
954 mutex_init(&ubi->ckvol_mutex);
955 mutex_init(&ubi->device_mutex);
956 spin_lock_init(&ubi->volumes_lock);
957 init_rwsem(&ubi->fm_protect);
958 init_rwsem(&ubi->fm_eba_sem);
960 ubi_msg(ubi, "attaching mtd%d", mtd->index);
962 err = io_init(ubi, max_beb_per1024);
967 ubi->peb_buf = vmalloc(ubi->peb_size);
971 #ifdef CONFIG_MTD_UBI_FASTMAP
972 ubi->fm_size = ubi_calc_fm_size(ubi);
973 ubi->fm_buf = vzalloc(ubi->fm_size);
977 err = ubi_attach(ubi, 0);
979 ubi_err(ubi, "failed to attach mtd%d, error %d",
984 if (ubi->autoresize_vol_id != -1) {
985 err = autoresize(ubi, ubi->autoresize_vol_id);
990 err = uif_init(ubi, &ref);
994 err = ubi_debugfs_init_dev(ubi);
998 ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
999 if (IS_ERR(ubi->bgt_thread)) {
1000 err = PTR_ERR(ubi->bgt_thread);
1001 ubi_err(ubi, "cannot spawn \"%s\", error %d",
1002 ubi->bgt_name, err);
1006 ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
1007 mtd->index, mtd->name, ubi->flash_size >> 20);
1008 ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
1009 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
1010 ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
1011 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
1012 ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
1013 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
1014 ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
1015 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1016 ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
1017 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
1019 ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1020 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1022 ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1023 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1026 * The below lock makes sure we do not race with 'ubi_thread()' which
1027 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1029 spin_lock(&ubi->wl_lock);
1030 ubi->thread_enabled = 1;
1031 wake_up_process(ubi->bgt_thread);
1032 spin_unlock(&ubi->wl_lock);
1034 ubi_devices[ubi_num] = ubi;
1035 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1039 ubi_debugfs_exit_dev(ubi);
1041 get_device(&ubi->dev);
1046 ubi_free_internal_volumes(ubi);
1049 vfree(ubi->peb_buf);
1052 put_device(&ubi->dev);
1059 * ubi_detach_mtd_dev - detach an MTD device.
1060 * @ubi_num: UBI device number to detach from
1061 * @anyway: detach MTD even if device reference count is not zero
1063 * This function destroys an UBI device number @ubi_num and detaches the
1064 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1065 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1068 * Note, the invocations of this function has to be serialized by the
1069 * @ubi_devices_mutex.
1071 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1073 struct ubi_device *ubi;
1075 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1078 ubi = ubi_get_device(ubi_num);
1082 spin_lock(&ubi_devices_lock);
1083 put_device(&ubi->dev);
1084 ubi->ref_count -= 1;
1085 if (ubi->ref_count) {
1087 spin_unlock(&ubi_devices_lock);
1090 /* This may only happen if there is a bug */
1091 ubi_err(ubi, "%s reference count %d, destroy anyway",
1092 ubi->ubi_name, ubi->ref_count);
1094 ubi_devices[ubi_num] = NULL;
1095 spin_unlock(&ubi_devices_lock);
1097 ubi_assert(ubi_num == ubi->ubi_num);
1098 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1099 ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1100 #ifdef CONFIG_MTD_UBI_FASTMAP
1101 /* If we don't write a new fastmap at detach time we lose all
1102 * EC updates that have been made since the last written fastmap.
1103 * In case of fastmap debugging we omit the update to simulate an
1104 * unclean shutdown. */
1105 if (!ubi_dbg_chk_fastmap(ubi))
1106 ubi_update_fastmap(ubi);
1109 * Before freeing anything, we have to stop the background thread to
1110 * prevent it from doing anything on this device while we are freeing.
1112 if (ubi->bgt_thread)
1113 kthread_stop(ubi->bgt_thread);
1116 * Get a reference to the device in order to prevent 'dev_release()'
1117 * from freeing the @ubi object.
1119 get_device(&ubi->dev);
1121 ubi_debugfs_exit_dev(ubi);
1125 ubi_free_internal_volumes(ubi);
1127 put_mtd_device(ubi->mtd);
1128 vfree(ubi->peb_buf);
1130 ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
1131 put_device(&ubi->dev);
1136 * open_mtd_by_chdev - open an MTD device by its character device node path.
1137 * @mtd_dev: MTD character device node path
1139 * This helper function opens an MTD device by its character node device path.
1140 * Returns MTD device description object in case of success and a negative
1141 * error code in case of failure.
1143 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1145 int err, major, minor, mode;
1148 /* Probably this is an MTD character device node path */
1149 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1151 return ERR_PTR(err);
1153 /* MTD device number is defined by the major / minor numbers */
1154 major = imajor(d_backing_inode(path.dentry));
1155 minor = iminor(d_backing_inode(path.dentry));
1156 mode = d_backing_inode(path.dentry)->i_mode;
1158 if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1159 return ERR_PTR(-EINVAL);
1163 * Just do not think the "/dev/mtdrX" devices support is need,
1164 * so do not support them to avoid doing extra work.
1166 return ERR_PTR(-EINVAL);
1168 return get_mtd_device(NULL, minor / 2);
1172 * open_mtd_device - open MTD device by name, character device path, or number.
1173 * @mtd_dev: name, character device node path, or MTD device device number
1175 * This function tries to open and MTD device described by @mtd_dev string,
1176 * which is first treated as ASCII MTD device number, and if it is not true, it
1177 * is treated as MTD device name, and if that is also not true, it is treated
1178 * as MTD character device node path. Returns MTD device description object in
1179 * case of success and a negative error code in case of failure.
1181 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1183 struct mtd_info *mtd;
1187 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1188 if (*endp != '\0' || mtd_dev == endp) {
1190 * This does not look like an ASCII integer, probably this is
1193 mtd = get_mtd_device_nm(mtd_dev);
1194 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1195 /* Probably this is an MTD character device node path */
1196 mtd = open_mtd_by_chdev(mtd_dev);
1198 mtd = get_mtd_device(NULL, mtd_num);
1203 static int __init ubi_init(void)
1207 /* Ensure that EC and VID headers have correct size */
1208 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1209 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1211 if (mtd_devs > UBI_MAX_DEVICES) {
1212 pr_err("UBI error: too many MTD devices, maximum is %d",
1217 /* Create base sysfs directory and sysfs files */
1218 err = class_register(&ubi_class);
1222 err = misc_register(&ubi_ctrl_cdev);
1224 pr_err("UBI error: cannot register device");
1228 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1229 sizeof(struct ubi_wl_entry),
1231 if (!ubi_wl_entry_slab) {
1236 err = ubi_debugfs_init();
1241 /* Attach MTD devices */
1242 for (i = 0; i < mtd_devs; i++) {
1243 struct mtd_dev_param *p = &mtd_dev_param[i];
1244 struct mtd_info *mtd;
1248 mtd = open_mtd_device(p->name);
1251 pr_err("UBI error: cannot open mtd %s, error %d",
1253 /* See comment below re-ubi_is_module(). */
1254 if (ubi_is_module())
1259 mutex_lock(&ubi_devices_mutex);
1260 err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1261 p->vid_hdr_offs, p->max_beb_per1024);
1262 mutex_unlock(&ubi_devices_mutex);
1264 pr_err("UBI error: cannot attach mtd%d",
1266 put_mtd_device(mtd);
1269 * Originally UBI stopped initializing on any error.
1270 * However, later on it was found out that this
1271 * behavior is not very good when UBI is compiled into
1272 * the kernel and the MTD devices to attach are passed
1273 * through the command line. Indeed, UBI failure
1274 * stopped whole boot sequence.
1276 * To fix this, we changed the behavior for the
1277 * non-module case, but preserved the old behavior for
1278 * the module case, just for compatibility. This is a
1279 * little inconsistent, though.
1281 if (ubi_is_module())
1286 err = ubiblock_init();
1288 pr_err("UBI error: block: cannot initialize, error %d", err);
1290 /* See comment above re-ubi_is_module(). */
1291 if (ubi_is_module())
1298 for (k = 0; k < i; k++)
1299 if (ubi_devices[k]) {
1300 mutex_lock(&ubi_devices_mutex);
1301 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1302 mutex_unlock(&ubi_devices_mutex);
1306 kmem_cache_destroy(ubi_wl_entry_slab);
1308 misc_deregister(&ubi_ctrl_cdev);
1310 class_unregister(&ubi_class);
1311 pr_err("UBI error: cannot initialize UBI, error %d", err);
1314 late_initcall(ubi_init);
1316 static void __exit ubi_exit(void)
1322 for (i = 0; i < UBI_MAX_DEVICES; i++)
1323 if (ubi_devices[i]) {
1324 mutex_lock(&ubi_devices_mutex);
1325 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1326 mutex_unlock(&ubi_devices_mutex);
1329 kmem_cache_destroy(ubi_wl_entry_slab);
1330 misc_deregister(&ubi_ctrl_cdev);
1331 class_unregister(&ubi_class);
1333 module_exit(ubi_exit);
1336 * bytes_str_to_int - convert a number of bytes string into an integer.
1337 * @str: the string to convert
1339 * This function returns positive resulting integer in case of success and a
1340 * negative error code in case of failure.
1342 static int __init bytes_str_to_int(const char *str)
1345 unsigned long result;
1347 result = simple_strtoul(str, &endp, 0);
1348 if (str == endp || result >= INT_MAX) {
1349 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1360 if (endp[1] == 'i' && endp[2] == 'B')
1365 pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1373 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1374 * @val: the parameter value to parse
1377 * This function returns zero in case of success and a negative error code in
1380 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1383 struct mtd_dev_param *p;
1384 char buf[MTD_PARAM_LEN_MAX];
1385 char *pbuf = &buf[0];
1386 char *tokens[MTD_PARAM_MAX_COUNT], *token;
1391 if (mtd_devs == UBI_MAX_DEVICES) {
1392 pr_err("UBI error: too many parameters, max. is %d\n",
1397 len = strnlen(val, MTD_PARAM_LEN_MAX);
1398 if (len == MTD_PARAM_LEN_MAX) {
1399 pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1400 val, MTD_PARAM_LEN_MAX);
1405 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1411 /* Get rid of the final newline */
1412 if (buf[len - 1] == '\n')
1413 buf[len - 1] = '\0';
1415 for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1416 tokens[i] = strsep(&pbuf, ",");
1419 pr_err("UBI error: too many arguments at \"%s\"\n", val);
1423 p = &mtd_dev_param[mtd_devs];
1424 strcpy(&p->name[0], tokens[0]);
1428 p->vid_hdr_offs = bytes_str_to_int(token);
1430 if (p->vid_hdr_offs < 0)
1431 return p->vid_hdr_offs;
1436 int err = kstrtoint(token, 10, &p->max_beb_per1024);
1439 pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1447 int err = kstrtoint(token, 10, &p->ubi_num);
1450 pr_err("UBI error: bad value for ubi_num parameter: %s",
1455 p->ubi_num = UBI_DEV_NUM_AUTO;
1461 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1462 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1463 "Multiple \"mtd\" parameters may be specified.\n"
1464 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1465 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1466 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1467 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1468 "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
1470 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1471 "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"
1472 "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"
1473 "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"
1474 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1475 #ifdef CONFIG_MTD_UBI_FASTMAP
1476 module_param(fm_autoconvert, bool, 0644);
1477 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1478 module_param(fm_debug, bool, 0);
1479 MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1481 MODULE_VERSION(__stringify(UBI_VERSION));
1482 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1483 MODULE_AUTHOR("Artem Bityutskiy");
1484 MODULE_LICENSE("GPL");