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>
46 /* Maximum length of the 'mtd=' parameter */
47 #define MTD_PARAM_LEN_MAX 64
49 /* Maximum number of comma-separated items in the 'mtd=' parameter */
50 #define MTD_PARAM_MAX_COUNT 3
52 /* Maximum value for the number of bad PEBs per 1024 PEBs */
53 #define MAX_MTD_UBI_BEB_LIMIT 768
55 #ifdef CONFIG_MTD_UBI_MODULE
56 #define ubi_is_module() 1
58 #define ubi_is_module() 0
62 * struct mtd_dev_param - MTD device parameter description data structure.
63 * @name: MTD character device node path, MTD device name, or MTD device number
65 * @vid_hdr_offs: VID header offset
66 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
68 struct mtd_dev_param {
69 char name[MTD_PARAM_LEN_MAX];
74 /* Numbers of elements set in the @mtd_dev_param array */
75 static int __initdata mtd_devs;
77 /* MTD devices specification parameters */
78 static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES];
79 #ifdef CONFIG_MTD_UBI_FASTMAP
80 /* UBI module parameter to enable fastmap automatically on non-fastmap images */
81 static bool fm_autoconvert;
83 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
84 struct class *ubi_class;
86 /* Slab cache for wear-leveling entries */
87 struct kmem_cache *ubi_wl_entry_slab;
89 /* UBI control character device */
90 static struct miscdevice ubi_ctrl_cdev = {
91 .minor = MISC_DYNAMIC_MINOR,
93 .fops = &ubi_ctrl_cdev_operations,
96 /* All UBI devices in system */
97 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
99 /* Serializes UBI devices creations and removals */
100 DEFINE_MUTEX(ubi_devices_mutex);
102 /* Protects @ubi_devices and @ubi->ref_count */
103 static DEFINE_SPINLOCK(ubi_devices_lock);
105 /* "Show" method for files in '/<sysfs>/class/ubi/' */
106 static ssize_t ubi_version_show(struct class *class,
107 struct class_attribute *attr, char *buf)
109 return sprintf(buf, "%d\n", UBI_VERSION);
112 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
113 static struct class_attribute ubi_version =
114 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
116 static ssize_t dev_attribute_show(struct device *dev,
117 struct device_attribute *attr, char *buf);
119 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
120 static struct device_attribute dev_eraseblock_size =
121 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
122 static struct device_attribute dev_avail_eraseblocks =
123 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
124 static struct device_attribute dev_total_eraseblocks =
125 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
126 static struct device_attribute dev_volumes_count =
127 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
128 static struct device_attribute dev_max_ec =
129 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
130 static struct device_attribute dev_reserved_for_bad =
131 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
132 static struct device_attribute dev_bad_peb_count =
133 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
134 static struct device_attribute dev_max_vol_count =
135 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
136 static struct device_attribute dev_min_io_size =
137 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
138 static struct device_attribute dev_bgt_enabled =
139 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
140 static struct device_attribute dev_mtd_num =
141 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
144 * ubi_volume_notify - send a volume change notification.
145 * @ubi: UBI device description object
146 * @vol: volume description object of the changed volume
147 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
149 * This is a helper function which notifies all subscribers about a volume
150 * change event (creation, removal, re-sizing, re-naming, updating). Returns
151 * zero in case of success and a negative error code in case of failure.
153 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
155 struct ubi_notification nt;
157 ubi_do_get_device_info(ubi, &nt.di);
158 ubi_do_get_volume_info(ubi, vol, &nt.vi);
160 #ifdef CONFIG_MTD_UBI_FASTMAP
162 case UBI_VOLUME_ADDED:
163 case UBI_VOLUME_REMOVED:
164 case UBI_VOLUME_RESIZED:
165 case UBI_VOLUME_RENAMED:
166 if (ubi_update_fastmap(ubi)) {
167 ubi_err("Unable to update fastmap!");
172 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
176 * ubi_notify_all - send a notification to all volumes.
177 * @ubi: UBI device description object
178 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
179 * @nb: the notifier to call
181 * This function walks all volumes of UBI device @ubi and sends the @ntype
182 * notification for each volume. If @nb is %NULL, then all registered notifiers
183 * are called, otherwise only the @nb notifier is called. Returns the number of
184 * sent notifications.
186 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
188 struct ubi_notification nt;
191 ubi_do_get_device_info(ubi, &nt.di);
193 mutex_lock(&ubi->device_mutex);
194 for (i = 0; i < ubi->vtbl_slots; i++) {
196 * Since the @ubi->device is locked, and we are not going to
197 * change @ubi->volumes, we do not have to lock
198 * @ubi->volumes_lock.
200 if (!ubi->volumes[i])
203 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
205 nb->notifier_call(nb, ntype, &nt);
207 blocking_notifier_call_chain(&ubi_notifiers, ntype,
211 mutex_unlock(&ubi->device_mutex);
217 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
218 * @nb: the notifier to call
220 * This function walks all UBI devices and volumes and sends the
221 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
222 * registered notifiers are called, otherwise only the @nb notifier is called.
223 * Returns the number of sent notifications.
225 int ubi_enumerate_volumes(struct notifier_block *nb)
230 * Since the @ubi_devices_mutex is locked, and we are not going to
231 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
233 for (i = 0; i < UBI_MAX_DEVICES; i++) {
234 struct ubi_device *ubi = ubi_devices[i];
238 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
245 * ubi_get_device - get UBI device.
246 * @ubi_num: UBI device number
248 * This function returns UBI device description object for UBI device number
249 * @ubi_num, or %NULL if the device does not exist. This function increases the
250 * device reference count to prevent removal of the device. In other words, the
251 * device cannot be removed if its reference count is not zero.
253 struct ubi_device *ubi_get_device(int ubi_num)
255 struct ubi_device *ubi;
257 spin_lock(&ubi_devices_lock);
258 ubi = ubi_devices[ubi_num];
260 ubi_assert(ubi->ref_count >= 0);
262 get_device(&ubi->dev);
264 spin_unlock(&ubi_devices_lock);
270 * ubi_put_device - drop an UBI device reference.
271 * @ubi: UBI device description object
273 void ubi_put_device(struct ubi_device *ubi)
275 spin_lock(&ubi_devices_lock);
277 put_device(&ubi->dev);
278 spin_unlock(&ubi_devices_lock);
282 * ubi_get_by_major - get UBI device by character device major number.
283 * @major: major number
285 * This function is similar to 'ubi_get_device()', but it searches the device
286 * by its major number.
288 struct ubi_device *ubi_get_by_major(int major)
291 struct ubi_device *ubi;
293 spin_lock(&ubi_devices_lock);
294 for (i = 0; i < UBI_MAX_DEVICES; i++) {
295 ubi = ubi_devices[i];
296 if (ubi && MAJOR(ubi->cdev.dev) == major) {
297 ubi_assert(ubi->ref_count >= 0);
299 get_device(&ubi->dev);
300 spin_unlock(&ubi_devices_lock);
304 spin_unlock(&ubi_devices_lock);
310 * ubi_major2num - get UBI device number by character device major number.
311 * @major: major number
313 * This function searches UBI device number object by its major number. If UBI
314 * device was not found, this function returns -ENODEV, otherwise the UBI device
315 * number is returned.
317 int ubi_major2num(int major)
319 int i, ubi_num = -ENODEV;
321 spin_lock(&ubi_devices_lock);
322 for (i = 0; i < UBI_MAX_DEVICES; i++) {
323 struct ubi_device *ubi = ubi_devices[i];
325 if (ubi && MAJOR(ubi->cdev.dev) == major) {
326 ubi_num = ubi->ubi_num;
330 spin_unlock(&ubi_devices_lock);
335 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
336 static ssize_t dev_attribute_show(struct device *dev,
337 struct device_attribute *attr, char *buf)
340 struct ubi_device *ubi;
343 * The below code looks weird, but it actually makes sense. We get the
344 * UBI device reference from the contained 'struct ubi_device'. But it
345 * is unclear if the device was removed or not yet. Indeed, if the
346 * device was removed before we increased its reference count,
347 * 'ubi_get_device()' will return -ENODEV and we fail.
349 * Remember, 'struct ubi_device' is freed in the release function, so
350 * we still can use 'ubi->ubi_num'.
352 ubi = container_of(dev, struct ubi_device, dev);
353 ubi = ubi_get_device(ubi->ubi_num);
357 if (attr == &dev_eraseblock_size)
358 ret = sprintf(buf, "%d\n", ubi->leb_size);
359 else if (attr == &dev_avail_eraseblocks)
360 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
361 else if (attr == &dev_total_eraseblocks)
362 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
363 else if (attr == &dev_volumes_count)
364 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
365 else if (attr == &dev_max_ec)
366 ret = sprintf(buf, "%d\n", ubi->max_ec);
367 else if (attr == &dev_reserved_for_bad)
368 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
369 else if (attr == &dev_bad_peb_count)
370 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
371 else if (attr == &dev_max_vol_count)
372 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
373 else if (attr == &dev_min_io_size)
374 ret = sprintf(buf, "%d\n", ubi->min_io_size);
375 else if (attr == &dev_bgt_enabled)
376 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
377 else if (attr == &dev_mtd_num)
378 ret = sprintf(buf, "%d\n", ubi->mtd->index);
386 static void dev_release(struct device *dev)
388 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
394 * ubi_sysfs_init - initialize sysfs for an UBI device.
395 * @ubi: UBI device description object
396 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
399 * This function returns zero in case of success and a negative error code in
402 static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
406 ubi->dev.release = dev_release;
407 ubi->dev.devt = ubi->cdev.dev;
408 ubi->dev.class = ubi_class;
409 dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
410 err = device_register(&ubi->dev);
415 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
418 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
421 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
424 err = device_create_file(&ubi->dev, &dev_volumes_count);
427 err = device_create_file(&ubi->dev, &dev_max_ec);
430 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
433 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
436 err = device_create_file(&ubi->dev, &dev_max_vol_count);
439 err = device_create_file(&ubi->dev, &dev_min_io_size);
442 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
445 err = device_create_file(&ubi->dev, &dev_mtd_num);
450 * ubi_sysfs_close - close sysfs for an UBI device.
451 * @ubi: UBI device description object
453 static void ubi_sysfs_close(struct ubi_device *ubi)
455 device_remove_file(&ubi->dev, &dev_mtd_num);
456 device_remove_file(&ubi->dev, &dev_bgt_enabled);
457 device_remove_file(&ubi->dev, &dev_min_io_size);
458 device_remove_file(&ubi->dev, &dev_max_vol_count);
459 device_remove_file(&ubi->dev, &dev_bad_peb_count);
460 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
461 device_remove_file(&ubi->dev, &dev_max_ec);
462 device_remove_file(&ubi->dev, &dev_volumes_count);
463 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
464 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
465 device_remove_file(&ubi->dev, &dev_eraseblock_size);
466 device_unregister(&ubi->dev);
470 * kill_volumes - destroy all user volumes.
471 * @ubi: UBI device description object
473 static void kill_volumes(struct ubi_device *ubi)
477 for (i = 0; i < ubi->vtbl_slots; i++)
479 ubi_free_volume(ubi, ubi->volumes[i]);
483 * uif_init - initialize user interfaces for an UBI device.
484 * @ubi: UBI device description object
485 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
486 * taken, otherwise set to %0
488 * This function initializes various user interfaces for an UBI device. If the
489 * initialization fails at an early stage, this function frees all the
490 * resources it allocated, returns an error, and @ref is set to %0. However,
491 * if the initialization fails after the UBI device was registered in the
492 * driver core subsystem, this function takes a reference to @ubi->dev, because
493 * otherwise the release function ('dev_release()') would free whole @ubi
494 * object. The @ref argument is set to %1 in this case. The caller has to put
497 * This function returns zero in case of success and a negative error code in
500 static int uif_init(struct ubi_device *ubi, int *ref)
506 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
509 * Major numbers for the UBI character devices are allocated
510 * dynamically. Major numbers of volume character devices are
511 * equivalent to ones of the corresponding UBI character device. Minor
512 * numbers of UBI character devices are 0, while minor numbers of
513 * volume character devices start from 1. Thus, we allocate one major
514 * number and ubi->vtbl_slots + 1 minor numbers.
516 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
518 ubi_err("cannot register UBI character devices");
522 ubi_assert(MINOR(dev) == 0);
523 cdev_init(&ubi->cdev, &ubi_cdev_operations);
524 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
525 ubi->cdev.owner = THIS_MODULE;
527 err = cdev_add(&ubi->cdev, dev, 1);
529 ubi_err("cannot add character device");
533 err = ubi_sysfs_init(ubi, ref);
537 for (i = 0; i < ubi->vtbl_slots; i++)
538 if (ubi->volumes[i]) {
539 err = ubi_add_volume(ubi, ubi->volumes[i]);
541 ubi_err("cannot add volume %d", i);
552 get_device(&ubi->dev);
553 ubi_sysfs_close(ubi);
554 cdev_del(&ubi->cdev);
556 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
557 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
562 * uif_close - close user interfaces for an UBI device.
563 * @ubi: UBI device description object
565 * Note, since this function un-registers UBI volume device objects (@vol->dev),
566 * the memory allocated voe the volumes is freed as well (in the release
569 static void uif_close(struct ubi_device *ubi)
572 ubi_sysfs_close(ubi);
573 cdev_del(&ubi->cdev);
574 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
578 * ubi_free_internal_volumes - free internal volumes.
579 * @ubi: UBI device description object
581 void ubi_free_internal_volumes(struct ubi_device *ubi)
585 for (i = ubi->vtbl_slots;
586 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
587 kfree(ubi->volumes[i]->eba_tbl);
588 kfree(ubi->volumes[i]);
592 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
594 int limit, device_pebs;
595 uint64_t device_size;
597 if (!max_beb_per1024)
601 * Here we are using size of the entire flash chip and
602 * not just the MTD partition size because the maximum
603 * number of bad eraseblocks is a percentage of the
604 * whole device and bad eraseblocks are not fairly
605 * distributed over the flash chip. So the worst case
606 * is that all the bad eraseblocks of the chip are in
607 * the MTD partition we are attaching (ubi->mtd).
609 device_size = mtd_get_device_size(ubi->mtd);
610 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
611 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
614 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
621 * io_init - initialize I/O sub-system for a given UBI device.
622 * @ubi: UBI device description object
623 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
625 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
627 * o EC header is always at offset zero - this cannot be changed;
628 * o VID header starts just after the EC header at the closest address
629 * aligned to @io->hdrs_min_io_size;
630 * o data starts just after the VID header at the closest address aligned to
633 * This function returns zero in case of success and a negative error code in
636 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
638 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
639 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
641 if (ubi->mtd->numeraseregions != 0) {
643 * Some flashes have several erase regions. Different regions
644 * may have different eraseblock size and other
645 * characteristics. It looks like mostly multi-region flashes
646 * have one "main" region and one or more small regions to
647 * store boot loader code or boot parameters or whatever. I
648 * guess we should just pick the largest region. But this is
651 ubi_err("multiple regions, not implemented");
655 if (ubi->vid_hdr_offset < 0)
659 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
660 * physical eraseblocks maximum.
663 ubi->peb_size = ubi->mtd->erasesize;
664 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
665 ubi->flash_size = ubi->mtd->size;
667 if (mtd_can_have_bb(ubi->mtd)) {
668 ubi->bad_allowed = 1;
669 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
672 if (ubi->mtd->type == MTD_NORFLASH) {
673 ubi_assert(ubi->mtd->writesize == 1);
677 ubi->min_io_size = ubi->mtd->writesize;
678 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
681 * Make sure minimal I/O unit is power of 2. Note, there is no
682 * fundamental reason for this assumption. It is just an optimization
683 * which allows us to avoid costly division operations.
685 if (!is_power_of_2(ubi->min_io_size)) {
686 ubi_err("min. I/O unit (%d) is not power of 2",
691 ubi_assert(ubi->hdrs_min_io_size > 0);
692 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
693 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
695 ubi->max_write_size = ubi->mtd->writebufsize;
697 * Maximum write size has to be greater or equivalent to min. I/O
698 * size, and be multiple of min. I/O size.
700 if (ubi->max_write_size < ubi->min_io_size ||
701 ubi->max_write_size % ubi->min_io_size ||
702 !is_power_of_2(ubi->max_write_size)) {
703 ubi_err("bad write buffer size %d for %d min. I/O unit",
704 ubi->max_write_size, ubi->min_io_size);
708 /* Calculate default aligned sizes of EC and VID headers */
709 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
710 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
712 dbg_gen("min_io_size %d", ubi->min_io_size);
713 dbg_gen("max_write_size %d", ubi->max_write_size);
714 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
715 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
716 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
718 if (ubi->vid_hdr_offset == 0)
720 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
723 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
724 ~(ubi->hdrs_min_io_size - 1);
725 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
726 ubi->vid_hdr_aloffset;
729 /* Similar for the data offset */
730 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
731 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
733 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
734 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
735 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
736 dbg_gen("leb_start %d", ubi->leb_start);
738 /* The shift must be aligned to 32-bit boundary */
739 if (ubi->vid_hdr_shift % 4) {
740 ubi_err("unaligned VID header shift %d",
746 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
747 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
748 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
749 ubi->leb_start & (ubi->min_io_size - 1)) {
750 ubi_err("bad VID header (%d) or data offsets (%d)",
751 ubi->vid_hdr_offset, ubi->leb_start);
756 * Set maximum amount of physical erroneous eraseblocks to be 10%.
757 * Erroneous PEB are those which have read errors.
759 ubi->max_erroneous = ubi->peb_count / 10;
760 if (ubi->max_erroneous < 16)
761 ubi->max_erroneous = 16;
762 dbg_gen("max_erroneous %d", ubi->max_erroneous);
765 * It may happen that EC and VID headers are situated in one minimal
766 * I/O unit. In this case we can only accept this UBI image in
769 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
770 ubi_warn("EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
774 ubi->leb_size = ubi->peb_size - ubi->leb_start;
776 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
777 ubi_msg("MTD device %d is write-protected, attach in read-only mode",
783 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
784 * unfortunately, MTD does not provide this information. We should loop
785 * over all physical eraseblocks and invoke mtd->block_is_bad() for
786 * each physical eraseblock. So, we leave @ubi->bad_peb_count
787 * uninitialized so far.
794 * autoresize - re-size the volume which has the "auto-resize" flag set.
795 * @ubi: UBI device description object
796 * @vol_id: ID of the volume to re-size
798 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
799 * the volume table to the largest possible size. See comments in ubi-header.h
800 * for more description of the flag. Returns zero in case of success and a
801 * negative error code in case of failure.
803 static int autoresize(struct ubi_device *ubi, int vol_id)
805 struct ubi_volume_desc desc;
806 struct ubi_volume *vol = ubi->volumes[vol_id];
807 int err, old_reserved_pebs = vol->reserved_pebs;
810 ubi_warn("skip auto-resize because of R/O mode");
815 * Clear the auto-resize flag in the volume in-memory copy of the
816 * volume table, and 'ubi_resize_volume()' will propagate this change
819 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
821 if (ubi->avail_pebs == 0) {
822 struct ubi_vtbl_record vtbl_rec;
825 * No available PEBs to re-size the volume, clear the flag on
828 vtbl_rec = ubi->vtbl[vol_id];
829 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
831 ubi_err("cannot clean auto-resize flag for volume %d",
835 err = ubi_resize_volume(&desc,
836 old_reserved_pebs + ubi->avail_pebs);
838 ubi_err("cannot auto-resize volume %d", vol_id);
844 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
845 vol->name, old_reserved_pebs, vol->reserved_pebs);
850 * ubi_attach_mtd_dev - attach an MTD device.
851 * @mtd: MTD device description object
852 * @ubi_num: number to assign to the new UBI device
853 * @vid_hdr_offset: VID header offset
854 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
856 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
857 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
858 * which case this function finds a vacant device number and assigns it
859 * automatically. Returns the new UBI device number in case of success and a
860 * negative error code in case of failure.
862 * Note, the invocations of this function has to be serialized by the
863 * @ubi_devices_mutex.
865 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
866 int vid_hdr_offset, int max_beb_per1024)
868 struct ubi_device *ubi;
871 if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
874 if (!max_beb_per1024)
875 max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
878 * Check if we already have the same MTD device attached.
880 * Note, this function assumes that UBI devices creations and deletions
881 * are serialized, so it does not take the &ubi_devices_lock.
883 for (i = 0; i < UBI_MAX_DEVICES; i++) {
884 ubi = ubi_devices[i];
885 if (ubi && mtd->index == ubi->mtd->index) {
886 ubi_err("mtd%d is already attached to ubi%d",
893 * Make sure this MTD device is not emulated on top of an UBI volume
894 * already. Well, generally this recursion works fine, but there are
895 * different problems like the UBI module takes a reference to itself
896 * by attaching (and thus, opening) the emulated MTD device. This
897 * results in inability to unload the module. And in general it makes
898 * no sense to attach emulated MTD devices, so we prohibit this.
900 if (mtd->type == MTD_UBIVOLUME) {
901 ubi_err("refuse attaching mtd%d - it is already emulated on top of UBI",
906 if (ubi_num == UBI_DEV_NUM_AUTO) {
907 /* Search for an empty slot in the @ubi_devices array */
908 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
909 if (!ubi_devices[ubi_num])
911 if (ubi_num == UBI_MAX_DEVICES) {
912 ubi_err("only %d UBI devices may be created",
917 if (ubi_num >= UBI_MAX_DEVICES)
920 /* Make sure ubi_num is not busy */
921 if (ubi_devices[ubi_num]) {
922 ubi_err("ubi%d already exists", ubi_num);
927 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
932 ubi->ubi_num = ubi_num;
933 ubi->vid_hdr_offset = vid_hdr_offset;
934 ubi->autoresize_vol_id = -1;
936 #ifdef CONFIG_MTD_UBI_FASTMAP
937 ubi->fm_pool.used = ubi->fm_pool.size = 0;
938 ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
941 * fm_pool.max_size is 5% of the total number of PEBs but it's also
942 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
944 ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
945 ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
946 if (ubi->fm_pool.max_size < UBI_FM_MIN_POOL_SIZE)
947 ubi->fm_pool.max_size = UBI_FM_MIN_POOL_SIZE;
949 ubi->fm_wl_pool.max_size = UBI_FM_WL_POOL_SIZE;
950 ubi->fm_disabled = !fm_autoconvert;
952 if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
953 <= UBI_FM_MAX_START) {
954 ubi_err("More than %i PEBs are needed for fastmap, sorry.",
956 ubi->fm_disabled = 1;
959 ubi_msg("default fastmap pool size: %d", ubi->fm_pool.max_size);
960 ubi_msg("default fastmap WL pool size: %d", ubi->fm_wl_pool.max_size);
962 ubi->fm_disabled = 1;
964 mutex_init(&ubi->buf_mutex);
965 mutex_init(&ubi->ckvol_mutex);
966 mutex_init(&ubi->device_mutex);
967 spin_lock_init(&ubi->volumes_lock);
968 mutex_init(&ubi->fm_mutex);
969 init_rwsem(&ubi->fm_sem);
971 ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
973 err = io_init(ubi, max_beb_per1024);
978 ubi->peb_buf = vmalloc(ubi->peb_size);
982 #ifdef CONFIG_MTD_UBI_FASTMAP
983 ubi->fm_size = ubi_calc_fm_size(ubi);
984 ubi->fm_buf = vzalloc(ubi->fm_size);
988 err = ubi_attach(ubi, 0);
990 ubi_err("failed to attach mtd%d, error %d", mtd->index, err);
994 if (ubi->autoresize_vol_id != -1) {
995 err = autoresize(ubi, ubi->autoresize_vol_id);
1000 err = uif_init(ubi, &ref);
1004 err = ubi_debugfs_init_dev(ubi);
1008 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
1009 if (IS_ERR(ubi->bgt_thread)) {
1010 err = PTR_ERR(ubi->bgt_thread);
1011 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
1016 ubi_msg("attached mtd%d (name \"%s\", size %llu MiB) to ubi%d",
1017 mtd->index, mtd->name, ubi->flash_size >> 20, ubi_num);
1018 ubi_msg("PEB size: %d bytes (%d KiB), LEB size: %d bytes",
1019 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
1020 ubi_msg("min./max. I/O unit sizes: %d/%d, sub-page size %d",
1021 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
1022 ubi_msg("VID header offset: %d (aligned %d), data offset: %d",
1023 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
1024 ubi_msg("good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
1025 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1026 ubi_msg("user volume: %d, internal volumes: %d, max. volumes count: %d",
1027 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
1029 ubi_msg("max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1030 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1032 ubi_msg("available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1033 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1036 * The below lock makes sure we do not race with 'ubi_thread()' which
1037 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1039 spin_lock(&ubi->wl_lock);
1040 ubi->thread_enabled = 1;
1041 wake_up_process(ubi->bgt_thread);
1042 spin_unlock(&ubi->wl_lock);
1044 ubi_devices[ubi_num] = ubi;
1045 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1049 ubi_debugfs_exit_dev(ubi);
1051 get_device(&ubi->dev);
1056 ubi_free_internal_volumes(ubi);
1059 vfree(ubi->peb_buf);
1062 put_device(&ubi->dev);
1069 * ubi_detach_mtd_dev - detach an MTD device.
1070 * @ubi_num: UBI device number to detach from
1071 * @anyway: detach MTD even if device reference count is not zero
1073 * This function destroys an UBI device number @ubi_num and detaches the
1074 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1075 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1078 * Note, the invocations of this function has to be serialized by the
1079 * @ubi_devices_mutex.
1081 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1083 struct ubi_device *ubi;
1085 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1088 ubi = ubi_get_device(ubi_num);
1092 spin_lock(&ubi_devices_lock);
1093 put_device(&ubi->dev);
1094 ubi->ref_count -= 1;
1095 if (ubi->ref_count) {
1097 spin_unlock(&ubi_devices_lock);
1100 /* This may only happen if there is a bug */
1101 ubi_err("%s reference count %d, destroy anyway",
1102 ubi->ubi_name, ubi->ref_count);
1104 ubi_devices[ubi_num] = NULL;
1105 spin_unlock(&ubi_devices_lock);
1107 ubi_assert(ubi_num == ubi->ubi_num);
1108 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1109 ubi_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1110 #ifdef CONFIG_MTD_UBI_FASTMAP
1111 /* If we don't write a new fastmap at detach time we lose all
1112 * EC updates that have been made since the last written fastmap. */
1113 ubi_update_fastmap(ubi);
1116 * Before freeing anything, we have to stop the background thread to
1117 * prevent it from doing anything on this device while we are freeing.
1119 if (ubi->bgt_thread)
1120 kthread_stop(ubi->bgt_thread);
1123 * Get a reference to the device in order to prevent 'dev_release()'
1124 * from freeing the @ubi object.
1126 get_device(&ubi->dev);
1128 ubi_debugfs_exit_dev(ubi);
1132 ubi_free_internal_volumes(ubi);
1134 put_mtd_device(ubi->mtd);
1135 vfree(ubi->peb_buf);
1137 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1138 put_device(&ubi->dev);
1143 * open_mtd_by_chdev - open an MTD device by its character device node path.
1144 * @mtd_dev: MTD character device node path
1146 * This helper function opens an MTD device by its character node device path.
1147 * Returns MTD device description object in case of success and a negative
1148 * error code in case of failure.
1150 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1152 int err, major, minor, mode;
1155 /* Probably this is an MTD character device node path */
1156 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1158 return ERR_PTR(err);
1160 /* MTD device number is defined by the major / minor numbers */
1161 major = imajor(path.dentry->d_inode);
1162 minor = iminor(path.dentry->d_inode);
1163 mode = path.dentry->d_inode->i_mode;
1165 if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1166 return ERR_PTR(-EINVAL);
1170 * Just do not think the "/dev/mtdrX" devices support is need,
1171 * so do not support them to avoid doing extra work.
1173 return ERR_PTR(-EINVAL);
1175 return get_mtd_device(NULL, minor / 2);
1179 * open_mtd_device - open MTD device by name, character device path, or number.
1180 * @mtd_dev: name, character device node path, or MTD device device number
1182 * This function tries to open and MTD device described by @mtd_dev string,
1183 * which is first treated as ASCII MTD device number, and if it is not true, it
1184 * is treated as MTD device name, and if that is also not true, it is treated
1185 * as MTD character device node path. Returns MTD device description object in
1186 * case of success and a negative error code in case of failure.
1188 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1190 struct mtd_info *mtd;
1194 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1195 if (*endp != '\0' || mtd_dev == endp) {
1197 * This does not look like an ASCII integer, probably this is
1200 mtd = get_mtd_device_nm(mtd_dev);
1201 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1202 /* Probably this is an MTD character device node path */
1203 mtd = open_mtd_by_chdev(mtd_dev);
1205 mtd = get_mtd_device(NULL, mtd_num);
1210 static int __init ubi_init(void)
1214 /* Ensure that EC and VID headers have correct size */
1215 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1216 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1218 if (mtd_devs > UBI_MAX_DEVICES) {
1219 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1223 /* Create base sysfs directory and sysfs files */
1224 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1225 if (IS_ERR(ubi_class)) {
1226 err = PTR_ERR(ubi_class);
1227 ubi_err("cannot create UBI class");
1231 err = class_create_file(ubi_class, &ubi_version);
1233 ubi_err("cannot create sysfs file");
1237 err = misc_register(&ubi_ctrl_cdev);
1239 ubi_err("cannot register device");
1243 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1244 sizeof(struct ubi_wl_entry),
1246 if (!ubi_wl_entry_slab)
1249 err = ubi_debugfs_init();
1254 /* Attach MTD devices */
1255 for (i = 0; i < mtd_devs; i++) {
1256 struct mtd_dev_param *p = &mtd_dev_param[i];
1257 struct mtd_info *mtd;
1261 mtd = open_mtd_device(p->name);
1267 mutex_lock(&ubi_devices_mutex);
1268 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
1269 p->vid_hdr_offs, p->max_beb_per1024);
1270 mutex_unlock(&ubi_devices_mutex);
1272 ubi_err("cannot attach mtd%d", mtd->index);
1273 put_mtd_device(mtd);
1276 * Originally UBI stopped initializing on any error.
1277 * However, later on it was found out that this
1278 * behavior is not very good when UBI is compiled into
1279 * the kernel and the MTD devices to attach are passed
1280 * through the command line. Indeed, UBI failure
1281 * stopped whole boot sequence.
1283 * To fix this, we changed the behavior for the
1284 * non-module case, but preserved the old behavior for
1285 * the module case, just for compatibility. This is a
1286 * little inconsistent, though.
1288 if (ubi_is_module())
1296 for (k = 0; k < i; k++)
1297 if (ubi_devices[k]) {
1298 mutex_lock(&ubi_devices_mutex);
1299 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1300 mutex_unlock(&ubi_devices_mutex);
1304 kmem_cache_destroy(ubi_wl_entry_slab);
1306 misc_deregister(&ubi_ctrl_cdev);
1308 class_remove_file(ubi_class, &ubi_version);
1310 class_destroy(ubi_class);
1312 ubi_err("UBI error: cannot initialize UBI, error %d", err);
1315 late_initcall(ubi_init);
1317 static void __exit ubi_exit(void)
1321 for (i = 0; i < UBI_MAX_DEVICES; i++)
1322 if (ubi_devices[i]) {
1323 mutex_lock(&ubi_devices_mutex);
1324 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1325 mutex_unlock(&ubi_devices_mutex);
1328 kmem_cache_destroy(ubi_wl_entry_slab);
1329 misc_deregister(&ubi_ctrl_cdev);
1330 class_remove_file(ubi_class, &ubi_version);
1331 class_destroy(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 ubi_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1360 if (endp[1] == 'i' && endp[2] == 'B')
1365 ubi_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];
1391 if (mtd_devs == UBI_MAX_DEVICES) {
1392 ubi_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 ubi_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 ubi_err("UBI error: too many arguments at \"%s\"\n", val);
1423 p = &mtd_dev_param[mtd_devs];
1424 strcpy(&p->name[0], tokens[0]);
1427 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1429 if (p->vid_hdr_offs < 0)
1430 return p->vid_hdr_offs;
1433 int err = kstrtoint(tokens[2], 10, &p->max_beb_per1024);
1436 ubi_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1446 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1447 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024]].\n"
1448 "Multiple \"mtd\" parameters may be specified.\n"
1449 "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1450 "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1451 "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1452 __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1454 "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1455 "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"
1456 "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"
1457 "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1458 #ifdef CONFIG_MTD_UBI_FASTMAP
1459 module_param(fm_autoconvert, bool, 0644);
1460 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1462 MODULE_VERSION(__stringify(UBI_VERSION));
1463 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1464 MODULE_AUTHOR("Artem Bityutskiy");
1465 MODULE_LICENSE("GPL");