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 #ifdef CONFIG_MTD_UBI_MODULE
50 #define ubi_is_module() 1
52 #define ubi_is_module() 0
56 * struct mtd_dev_param - MTD device parameter description data structure.
57 * @name: MTD character device node path, MTD device name, or MTD device number
59 * @vid_hdr_offs: VID header offset
61 struct mtd_dev_param {
62 char name[MTD_PARAM_LEN_MAX];
66 /* Numbers of elements set in the @mtd_dev_param array */
67 static int __initdata mtd_devs;
69 /* MTD devices specification parameters */
70 static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES];
72 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
73 struct class *ubi_class;
75 /* Slab cache for wear-leveling entries */
76 struct kmem_cache *ubi_wl_entry_slab;
78 /* UBI control character device */
79 static struct miscdevice ubi_ctrl_cdev = {
80 .minor = MISC_DYNAMIC_MINOR,
82 .fops = &ubi_ctrl_cdev_operations,
85 /* All UBI devices in system */
86 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
88 /* Serializes UBI devices creations and removals */
89 DEFINE_MUTEX(ubi_devices_mutex);
91 /* Protects @ubi_devices and @ubi->ref_count */
92 static DEFINE_SPINLOCK(ubi_devices_lock);
94 /* "Show" method for files in '/<sysfs>/class/ubi/' */
95 static ssize_t ubi_version_show(struct class *class,
96 struct class_attribute *attr, char *buf)
98 return sprintf(buf, "%d\n", UBI_VERSION);
101 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
102 static struct class_attribute ubi_version =
103 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
105 static ssize_t dev_attribute_show(struct device *dev,
106 struct device_attribute *attr, char *buf);
108 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
109 static struct device_attribute dev_eraseblock_size =
110 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
111 static struct device_attribute dev_avail_eraseblocks =
112 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
113 static struct device_attribute dev_total_eraseblocks =
114 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
115 static struct device_attribute dev_volumes_count =
116 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
117 static struct device_attribute dev_max_ec =
118 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
119 static struct device_attribute dev_reserved_for_bad =
120 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
121 static struct device_attribute dev_bad_peb_count =
122 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
123 static struct device_attribute dev_max_vol_count =
124 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
125 static struct device_attribute dev_min_io_size =
126 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
127 static struct device_attribute dev_bgt_enabled =
128 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
129 static struct device_attribute dev_mtd_num =
130 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
133 * ubi_volume_notify - send a volume change notification.
134 * @ubi: UBI device description object
135 * @vol: volume description object of the changed volume
136 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
138 * This is a helper function which notifies all subscribers about a volume
139 * change event (creation, removal, re-sizing, re-naming, updating). Returns
140 * zero in case of success and a negative error code in case of failure.
142 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
144 struct ubi_notification nt;
146 ubi_do_get_device_info(ubi, &nt.di);
147 ubi_do_get_volume_info(ubi, vol, &nt.vi);
148 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
152 * ubi_notify_all - send a notification to all volumes.
153 * @ubi: UBI device description object
154 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
155 * @nb: the notifier to call
157 * This function walks all volumes of UBI device @ubi and sends the @ntype
158 * notification for each volume. If @nb is %NULL, then all registered notifiers
159 * are called, otherwise only the @nb notifier is called. Returns the number of
160 * sent notifications.
162 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
164 struct ubi_notification nt;
167 ubi_do_get_device_info(ubi, &nt.di);
169 mutex_lock(&ubi->device_mutex);
170 for (i = 0; i < ubi->vtbl_slots; i++) {
172 * Since the @ubi->device is locked, and we are not going to
173 * change @ubi->volumes, we do not have to lock
174 * @ubi->volumes_lock.
176 if (!ubi->volumes[i])
179 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
181 nb->notifier_call(nb, ntype, &nt);
183 blocking_notifier_call_chain(&ubi_notifiers, ntype,
187 mutex_unlock(&ubi->device_mutex);
193 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
194 * @nb: the notifier to call
196 * This function walks all UBI devices and volumes and sends the
197 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
198 * registered notifiers are called, otherwise only the @nb notifier is called.
199 * Returns the number of sent notifications.
201 int ubi_enumerate_volumes(struct notifier_block *nb)
206 * Since the @ubi_devices_mutex is locked, and we are not going to
207 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
209 for (i = 0; i < UBI_MAX_DEVICES; i++) {
210 struct ubi_device *ubi = ubi_devices[i];
214 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
221 * ubi_get_device - get UBI device.
222 * @ubi_num: UBI device number
224 * This function returns UBI device description object for UBI device number
225 * @ubi_num, or %NULL if the device does not exist. This function increases the
226 * device reference count to prevent removal of the device. In other words, the
227 * device cannot be removed if its reference count is not zero.
229 struct ubi_device *ubi_get_device(int ubi_num)
231 struct ubi_device *ubi;
233 spin_lock(&ubi_devices_lock);
234 ubi = ubi_devices[ubi_num];
236 ubi_assert(ubi->ref_count >= 0);
238 get_device(&ubi->dev);
240 spin_unlock(&ubi_devices_lock);
246 * ubi_put_device - drop an UBI device reference.
247 * @ubi: UBI device description object
249 void ubi_put_device(struct ubi_device *ubi)
251 spin_lock(&ubi_devices_lock);
253 put_device(&ubi->dev);
254 spin_unlock(&ubi_devices_lock);
258 * ubi_get_by_major - get UBI device by character device major number.
259 * @major: major number
261 * This function is similar to 'ubi_get_device()', but it searches the device
262 * by its major number.
264 struct ubi_device *ubi_get_by_major(int major)
267 struct ubi_device *ubi;
269 spin_lock(&ubi_devices_lock);
270 for (i = 0; i < UBI_MAX_DEVICES; i++) {
271 ubi = ubi_devices[i];
272 if (ubi && MAJOR(ubi->cdev.dev) == major) {
273 ubi_assert(ubi->ref_count >= 0);
275 get_device(&ubi->dev);
276 spin_unlock(&ubi_devices_lock);
280 spin_unlock(&ubi_devices_lock);
286 * ubi_major2num - get UBI device number by character device major number.
287 * @major: major number
289 * This function searches UBI device number object by its major number. If UBI
290 * device was not found, this function returns -ENODEV, otherwise the UBI device
291 * number is returned.
293 int ubi_major2num(int major)
295 int i, ubi_num = -ENODEV;
297 spin_lock(&ubi_devices_lock);
298 for (i = 0; i < UBI_MAX_DEVICES; i++) {
299 struct ubi_device *ubi = ubi_devices[i];
301 if (ubi && MAJOR(ubi->cdev.dev) == major) {
302 ubi_num = ubi->ubi_num;
306 spin_unlock(&ubi_devices_lock);
311 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
312 static ssize_t dev_attribute_show(struct device *dev,
313 struct device_attribute *attr, char *buf)
316 struct ubi_device *ubi;
319 * The below code looks weird, but it actually makes sense. We get the
320 * UBI device reference from the contained 'struct ubi_device'. But it
321 * is unclear if the device was removed or not yet. Indeed, if the
322 * device was removed before we increased its reference count,
323 * 'ubi_get_device()' will return -ENODEV and we fail.
325 * Remember, 'struct ubi_device' is freed in the release function, so
326 * we still can use 'ubi->ubi_num'.
328 ubi = container_of(dev, struct ubi_device, dev);
329 ubi = ubi_get_device(ubi->ubi_num);
333 if (attr == &dev_eraseblock_size)
334 ret = sprintf(buf, "%d\n", ubi->leb_size);
335 else if (attr == &dev_avail_eraseblocks)
336 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
337 else if (attr == &dev_total_eraseblocks)
338 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
339 else if (attr == &dev_volumes_count)
340 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
341 else if (attr == &dev_max_ec)
342 ret = sprintf(buf, "%d\n", ubi->max_ec);
343 else if (attr == &dev_reserved_for_bad)
344 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
345 else if (attr == &dev_bad_peb_count)
346 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
347 else if (attr == &dev_max_vol_count)
348 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
349 else if (attr == &dev_min_io_size)
350 ret = sprintf(buf, "%d\n", ubi->min_io_size);
351 else if (attr == &dev_bgt_enabled)
352 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
353 else if (attr == &dev_mtd_num)
354 ret = sprintf(buf, "%d\n", ubi->mtd->index);
362 static void dev_release(struct device *dev)
364 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
370 * ubi_sysfs_init - initialize sysfs for an UBI device.
371 * @ubi: UBI device description object
372 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
375 * This function returns zero in case of success and a negative error code in
378 static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
382 ubi->dev.release = dev_release;
383 ubi->dev.devt = ubi->cdev.dev;
384 ubi->dev.class = ubi_class;
385 dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
386 err = device_register(&ubi->dev);
391 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
394 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
397 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
400 err = device_create_file(&ubi->dev, &dev_volumes_count);
403 err = device_create_file(&ubi->dev, &dev_max_ec);
406 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
409 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
412 err = device_create_file(&ubi->dev, &dev_max_vol_count);
415 err = device_create_file(&ubi->dev, &dev_min_io_size);
418 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
421 err = device_create_file(&ubi->dev, &dev_mtd_num);
426 * ubi_sysfs_close - close sysfs for an UBI device.
427 * @ubi: UBI device description object
429 static void ubi_sysfs_close(struct ubi_device *ubi)
431 device_remove_file(&ubi->dev, &dev_mtd_num);
432 device_remove_file(&ubi->dev, &dev_bgt_enabled);
433 device_remove_file(&ubi->dev, &dev_min_io_size);
434 device_remove_file(&ubi->dev, &dev_max_vol_count);
435 device_remove_file(&ubi->dev, &dev_bad_peb_count);
436 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
437 device_remove_file(&ubi->dev, &dev_max_ec);
438 device_remove_file(&ubi->dev, &dev_volumes_count);
439 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
440 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
441 device_remove_file(&ubi->dev, &dev_eraseblock_size);
442 device_unregister(&ubi->dev);
446 * kill_volumes - destroy all user volumes.
447 * @ubi: UBI device description object
449 static void kill_volumes(struct ubi_device *ubi)
453 for (i = 0; i < ubi->vtbl_slots; i++)
455 ubi_free_volume(ubi, ubi->volumes[i]);
459 * uif_init - initialize user interfaces for an UBI device.
460 * @ubi: UBI device description object
461 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
462 * taken, otherwise set to %0
464 * This function initializes various user interfaces for an UBI device. If the
465 * initialization fails at an early stage, this function frees all the
466 * resources it allocated, returns an error, and @ref is set to %0. However,
467 * if the initialization fails after the UBI device was registered in the
468 * driver core subsystem, this function takes a reference to @ubi->dev, because
469 * otherwise the release function ('dev_release()') would free whole @ubi
470 * object. The @ref argument is set to %1 in this case. The caller has to put
473 * This function returns zero in case of success and a negative error code in
476 static int uif_init(struct ubi_device *ubi, int *ref)
482 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
485 * Major numbers for the UBI character devices are allocated
486 * dynamically. Major numbers of volume character devices are
487 * equivalent to ones of the corresponding UBI character device. Minor
488 * numbers of UBI character devices are 0, while minor numbers of
489 * volume character devices start from 1. Thus, we allocate one major
490 * number and ubi->vtbl_slots + 1 minor numbers.
492 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
494 ubi_err("cannot register UBI character devices");
498 ubi_assert(MINOR(dev) == 0);
499 cdev_init(&ubi->cdev, &ubi_cdev_operations);
500 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
501 ubi->cdev.owner = THIS_MODULE;
503 err = cdev_add(&ubi->cdev, dev, 1);
505 ubi_err("cannot add character device");
509 err = ubi_sysfs_init(ubi, ref);
513 for (i = 0; i < ubi->vtbl_slots; i++)
514 if (ubi->volumes[i]) {
515 err = ubi_add_volume(ubi, ubi->volumes[i]);
517 ubi_err("cannot add volume %d", i);
528 get_device(&ubi->dev);
529 ubi_sysfs_close(ubi);
530 cdev_del(&ubi->cdev);
532 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
533 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
538 * uif_close - close user interfaces for an UBI device.
539 * @ubi: UBI device description object
541 * Note, since this function un-registers UBI volume device objects (@vol->dev),
542 * the memory allocated voe the volumes is freed as well (in the release
545 static void uif_close(struct ubi_device *ubi)
548 ubi_sysfs_close(ubi);
549 cdev_del(&ubi->cdev);
550 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
554 * ubi_free_internal_volumes - free internal volumes.
555 * @ubi: UBI device description object
557 void ubi_free_internal_volumes(struct ubi_device *ubi)
561 for (i = ubi->vtbl_slots;
562 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
563 kfree(ubi->volumes[i]->eba_tbl);
564 kfree(ubi->volumes[i]);
568 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
570 int limit, device_pebs;
571 uint64_t device_size;
573 if (!max_beb_per1024)
577 * Here we are using size of the entire flash chip and
578 * not just the MTD partition size because the maximum
579 * number of bad eraseblocks is a percentage of the
580 * whole device and bad eraseblocks are not fairly
581 * distributed over the flash chip. So the worst case
582 * is that all the bad eraseblocks of the chip are in
583 * the MTD partition we are attaching (ubi->mtd).
585 device_size = mtd_get_device_size(ubi->mtd);
586 device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
587 limit = mult_frac(device_pebs, max_beb_per1024, 1024);
590 if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
597 * io_init - initialize I/O sub-system for a given UBI device.
598 * @ubi: UBI device description object
600 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
602 * o EC header is always at offset zero - this cannot be changed;
603 * o VID header starts just after the EC header at the closest address
604 * aligned to @io->hdrs_min_io_size;
605 * o data starts just after the VID header at the closest address aligned to
608 * This function returns zero in case of success and a negative error code in
611 static int io_init(struct ubi_device *ubi)
613 const int max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
615 if (ubi->mtd->numeraseregions != 0) {
617 * Some flashes have several erase regions. Different regions
618 * may have different eraseblock size and other
619 * characteristics. It looks like mostly multi-region flashes
620 * have one "main" region and one or more small regions to
621 * store boot loader code or boot parameters or whatever. I
622 * guess we should just pick the largest region. But this is
625 ubi_err("multiple regions, not implemented");
629 if (ubi->vid_hdr_offset < 0)
633 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
634 * physical eraseblocks maximum.
637 ubi->peb_size = ubi->mtd->erasesize;
638 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
639 ubi->flash_size = ubi->mtd->size;
641 if (mtd_can_have_bb(ubi->mtd)) {
642 ubi->bad_allowed = 1;
643 ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
646 if (ubi->mtd->type == MTD_NORFLASH) {
647 ubi_assert(ubi->mtd->writesize == 1);
651 ubi->min_io_size = ubi->mtd->writesize;
652 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
655 * Make sure minimal I/O unit is power of 2. Note, there is no
656 * fundamental reason for this assumption. It is just an optimization
657 * which allows us to avoid costly division operations.
659 if (!is_power_of_2(ubi->min_io_size)) {
660 ubi_err("min. I/O unit (%d) is not power of 2",
665 ubi_assert(ubi->hdrs_min_io_size > 0);
666 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
667 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
669 ubi->max_write_size = ubi->mtd->writebufsize;
671 * Maximum write size has to be greater or equivalent to min. I/O
672 * size, and be multiple of min. I/O size.
674 if (ubi->max_write_size < ubi->min_io_size ||
675 ubi->max_write_size % ubi->min_io_size ||
676 !is_power_of_2(ubi->max_write_size)) {
677 ubi_err("bad write buffer size %d for %d min. I/O unit",
678 ubi->max_write_size, ubi->min_io_size);
682 /* Calculate default aligned sizes of EC and VID headers */
683 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
684 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
686 dbg_msg("min_io_size %d", ubi->min_io_size);
687 dbg_msg("max_write_size %d", ubi->max_write_size);
688 dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
689 dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
690 dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
692 if (ubi->vid_hdr_offset == 0)
694 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
697 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
698 ~(ubi->hdrs_min_io_size - 1);
699 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
700 ubi->vid_hdr_aloffset;
703 /* Similar for the data offset */
704 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
705 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
707 dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
708 dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
709 dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
710 dbg_msg("leb_start %d", ubi->leb_start);
712 /* The shift must be aligned to 32-bit boundary */
713 if (ubi->vid_hdr_shift % 4) {
714 ubi_err("unaligned VID header shift %d",
720 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
721 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
722 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
723 ubi->leb_start & (ubi->min_io_size - 1)) {
724 ubi_err("bad VID header (%d) or data offsets (%d)",
725 ubi->vid_hdr_offset, ubi->leb_start);
730 * Set maximum amount of physical erroneous eraseblocks to be 10%.
731 * Erroneous PEB are those which have read errors.
733 ubi->max_erroneous = ubi->peb_count / 10;
734 if (ubi->max_erroneous < 16)
735 ubi->max_erroneous = 16;
736 dbg_msg("max_erroneous %d", ubi->max_erroneous);
739 * It may happen that EC and VID headers are situated in one minimal
740 * I/O unit. In this case we can only accept this UBI image in
743 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
744 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
745 "switch to read-only mode");
749 ubi->leb_size = ubi->peb_size - ubi->leb_start;
751 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
752 ubi_msg("MTD device %d is write-protected, attach in "
753 "read-only mode", ubi->mtd->index);
757 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
758 ubi->peb_size, ubi->peb_size >> 10);
759 ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
760 ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
761 if (ubi->hdrs_min_io_size != ubi->min_io_size)
762 ubi_msg("sub-page size: %d",
763 ubi->hdrs_min_io_size);
764 ubi_msg("VID header offset: %d (aligned %d)",
765 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
766 ubi_msg("data offset: %d", ubi->leb_start);
769 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
770 * unfortunately, MTD does not provide this information. We should loop
771 * over all physical eraseblocks and invoke mtd->block_is_bad() for
772 * each physical eraseblock. So, we leave @ubi->bad_peb_count
773 * uninitialized so far.
780 * autoresize - re-size the volume which has the "auto-resize" flag set.
781 * @ubi: UBI device description object
782 * @vol_id: ID of the volume to re-size
784 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
785 * the volume table to the largest possible size. See comments in ubi-header.h
786 * for more description of the flag. Returns zero in case of success and a
787 * negative error code in case of failure.
789 static int autoresize(struct ubi_device *ubi, int vol_id)
791 struct ubi_volume_desc desc;
792 struct ubi_volume *vol = ubi->volumes[vol_id];
793 int err, old_reserved_pebs = vol->reserved_pebs;
796 * Clear the auto-resize flag in the volume in-memory copy of the
797 * volume table, and 'ubi_resize_volume()' will propagate this change
800 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
802 if (ubi->avail_pebs == 0) {
803 struct ubi_vtbl_record vtbl_rec;
806 * No available PEBs to re-size the volume, clear the flag on
809 memcpy(&vtbl_rec, &ubi->vtbl[vol_id],
810 sizeof(struct ubi_vtbl_record));
811 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
813 ubi_err("cannot clean auto-resize flag for volume %d",
817 err = ubi_resize_volume(&desc,
818 old_reserved_pebs + ubi->avail_pebs);
820 ubi_err("cannot auto-resize volume %d", vol_id);
826 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
827 vol->name, old_reserved_pebs, vol->reserved_pebs);
832 * ubi_attach_mtd_dev - attach an MTD device.
833 * @mtd: MTD device description object
834 * @ubi_num: number to assign to the new UBI device
835 * @vid_hdr_offset: VID header offset
837 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
838 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
839 * which case this function finds a vacant device number and assigns it
840 * automatically. Returns the new UBI device number in case of success and a
841 * negative error code in case of failure.
843 * Note, the invocations of this function has to be serialized by the
844 * @ubi_devices_mutex.
846 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
848 struct ubi_device *ubi;
852 * Check if we already have the same MTD device attached.
854 * Note, this function assumes that UBI devices creations and deletions
855 * are serialized, so it does not take the &ubi_devices_lock.
857 for (i = 0; i < UBI_MAX_DEVICES; i++) {
858 ubi = ubi_devices[i];
859 if (ubi && mtd->index == ubi->mtd->index) {
860 ubi_err("mtd%d is already attached to ubi%d",
867 * Make sure this MTD device is not emulated on top of an UBI volume
868 * already. Well, generally this recursion works fine, but there are
869 * different problems like the UBI module takes a reference to itself
870 * by attaching (and thus, opening) the emulated MTD device. This
871 * results in inability to unload the module. And in general it makes
872 * no sense to attach emulated MTD devices, so we prohibit this.
874 if (mtd->type == MTD_UBIVOLUME) {
875 ubi_err("refuse attaching mtd%d - it is already emulated on "
876 "top of UBI", mtd->index);
880 if (ubi_num == UBI_DEV_NUM_AUTO) {
881 /* Search for an empty slot in the @ubi_devices array */
882 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
883 if (!ubi_devices[ubi_num])
885 if (ubi_num == UBI_MAX_DEVICES) {
886 ubi_err("only %d UBI devices may be created",
891 if (ubi_num >= UBI_MAX_DEVICES)
894 /* Make sure ubi_num is not busy */
895 if (ubi_devices[ubi_num]) {
896 ubi_err("ubi%d already exists", ubi_num);
901 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
906 ubi->ubi_num = ubi_num;
907 ubi->vid_hdr_offset = vid_hdr_offset;
908 ubi->autoresize_vol_id = -1;
910 mutex_init(&ubi->buf_mutex);
911 mutex_init(&ubi->ckvol_mutex);
912 mutex_init(&ubi->device_mutex);
913 spin_lock_init(&ubi->volumes_lock);
915 ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
916 dbg_msg("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
917 dbg_msg("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
924 ubi->peb_buf = vmalloc(ubi->peb_size);
928 err = ubi_debugging_init_dev(ubi);
932 err = ubi_attach(ubi);
934 ubi_err("failed to attach mtd%d, error %d", mtd->index, err);
938 if (ubi->autoresize_vol_id != -1) {
939 err = autoresize(ubi, ubi->autoresize_vol_id);
944 err = uif_init(ubi, &ref);
948 err = ubi_debugfs_init_dev(ubi);
952 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
953 if (IS_ERR(ubi->bgt_thread)) {
954 err = PTR_ERR(ubi->bgt_thread);
955 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
960 ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num);
961 ubi_msg("MTD device name: \"%s\"", mtd->name);
962 ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
963 ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
964 ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
965 ubi_msg("number of corrupted PEBs: %d", ubi->corr_peb_count);
966 ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
967 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
968 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
969 ubi_msg("number of user volumes: %d",
970 ubi->vol_count - UBI_INT_VOL_COUNT);
971 ubi_msg("available PEBs: %d", ubi->avail_pebs);
972 ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
973 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
975 ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
976 ubi_msg("image sequence number: %u", ubi->image_seq);
979 * The below lock makes sure we do not race with 'ubi_thread()' which
980 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
982 spin_lock(&ubi->wl_lock);
983 ubi->thread_enabled = 1;
984 wake_up_process(ubi->bgt_thread);
985 spin_unlock(&ubi->wl_lock);
987 ubi_devices[ubi_num] = ubi;
988 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
992 ubi_debugfs_exit_dev(ubi);
994 get_device(&ubi->dev);
999 ubi_free_internal_volumes(ubi);
1002 ubi_debugging_exit_dev(ubi);
1004 vfree(ubi->peb_buf);
1006 put_device(&ubi->dev);
1013 * ubi_detach_mtd_dev - detach an MTD device.
1014 * @ubi_num: UBI device number to detach from
1015 * @anyway: detach MTD even if device reference count is not zero
1017 * This function destroys an UBI device number @ubi_num and detaches the
1018 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1019 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1022 * Note, the invocations of this function has to be serialized by the
1023 * @ubi_devices_mutex.
1025 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1027 struct ubi_device *ubi;
1029 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1032 ubi = ubi_get_device(ubi_num);
1036 spin_lock(&ubi_devices_lock);
1037 put_device(&ubi->dev);
1038 ubi->ref_count -= 1;
1039 if (ubi->ref_count) {
1041 spin_unlock(&ubi_devices_lock);
1044 /* This may only happen if there is a bug */
1045 ubi_err("%s reference count %d, destroy anyway",
1046 ubi->ubi_name, ubi->ref_count);
1048 ubi_devices[ubi_num] = NULL;
1049 spin_unlock(&ubi_devices_lock);
1051 ubi_assert(ubi_num == ubi->ubi_num);
1052 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1053 dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1056 * Before freeing anything, we have to stop the background thread to
1057 * prevent it from doing anything on this device while we are freeing.
1059 if (ubi->bgt_thread)
1060 kthread_stop(ubi->bgt_thread);
1063 * Get a reference to the device in order to prevent 'dev_release()'
1064 * from freeing the @ubi object.
1066 get_device(&ubi->dev);
1068 ubi_debugfs_exit_dev(ubi);
1071 ubi_free_internal_volumes(ubi);
1073 put_mtd_device(ubi->mtd);
1074 ubi_debugging_exit_dev(ubi);
1075 vfree(ubi->peb_buf);
1076 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1077 put_device(&ubi->dev);
1082 * open_mtd_by_chdev - open an MTD device by its character device node path.
1083 * @mtd_dev: MTD character device node path
1085 * This helper function opens an MTD device by its character node device path.
1086 * Returns MTD device description object in case of success and a negative
1087 * error code in case of failure.
1089 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1091 int err, major, minor, mode;
1094 /* Probably this is an MTD character device node path */
1095 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1097 return ERR_PTR(err);
1099 /* MTD device number is defined by the major / minor numbers */
1100 major = imajor(path.dentry->d_inode);
1101 minor = iminor(path.dentry->d_inode);
1102 mode = path.dentry->d_inode->i_mode;
1104 if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1105 return ERR_PTR(-EINVAL);
1109 * Just do not think the "/dev/mtdrX" devices support is need,
1110 * so do not support them to avoid doing extra work.
1112 return ERR_PTR(-EINVAL);
1114 return get_mtd_device(NULL, minor / 2);
1118 * open_mtd_device - open MTD device by name, character device path, or number.
1119 * @mtd_dev: name, character device node path, or MTD device device number
1121 * This function tries to open and MTD device described by @mtd_dev string,
1122 * which is first treated as ASCII MTD device number, and if it is not true, it
1123 * is treated as MTD device name, and if that is also not true, it is treated
1124 * as MTD character device node path. Returns MTD device description object in
1125 * case of success and a negative error code in case of failure.
1127 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1129 struct mtd_info *mtd;
1133 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1134 if (*endp != '\0' || mtd_dev == endp) {
1136 * This does not look like an ASCII integer, probably this is
1139 mtd = get_mtd_device_nm(mtd_dev);
1140 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1141 /* Probably this is an MTD character device node path */
1142 mtd = open_mtd_by_chdev(mtd_dev);
1144 mtd = get_mtd_device(NULL, mtd_num);
1149 static int __init ubi_init(void)
1153 /* Ensure that EC and VID headers have correct size */
1154 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1155 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1157 if (mtd_devs > UBI_MAX_DEVICES) {
1158 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1162 /* Create base sysfs directory and sysfs files */
1163 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1164 if (IS_ERR(ubi_class)) {
1165 err = PTR_ERR(ubi_class);
1166 ubi_err("cannot create UBI class");
1170 err = class_create_file(ubi_class, &ubi_version);
1172 ubi_err("cannot create sysfs file");
1176 err = misc_register(&ubi_ctrl_cdev);
1178 ubi_err("cannot register device");
1182 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1183 sizeof(struct ubi_wl_entry),
1185 if (!ubi_wl_entry_slab)
1188 err = ubi_debugfs_init();
1193 /* Attach MTD devices */
1194 for (i = 0; i < mtd_devs; i++) {
1195 struct mtd_dev_param *p = &mtd_dev_param[i];
1196 struct mtd_info *mtd;
1200 mtd = open_mtd_device(p->name);
1206 mutex_lock(&ubi_devices_mutex);
1207 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
1209 mutex_unlock(&ubi_devices_mutex);
1211 ubi_err("cannot attach mtd%d", mtd->index);
1212 put_mtd_device(mtd);
1215 * Originally UBI stopped initializing on any error.
1216 * However, later on it was found out that this
1217 * behavior is not very good when UBI is compiled into
1218 * the kernel and the MTD devices to attach are passed
1219 * through the command line. Indeed, UBI failure
1220 * stopped whole boot sequence.
1222 * To fix this, we changed the behavior for the
1223 * non-module case, but preserved the old behavior for
1224 * the module case, just for compatibility. This is a
1225 * little inconsistent, though.
1227 if (ubi_is_module())
1235 for (k = 0; k < i; k++)
1236 if (ubi_devices[k]) {
1237 mutex_lock(&ubi_devices_mutex);
1238 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1239 mutex_unlock(&ubi_devices_mutex);
1243 kmem_cache_destroy(ubi_wl_entry_slab);
1245 misc_deregister(&ubi_ctrl_cdev);
1247 class_remove_file(ubi_class, &ubi_version);
1249 class_destroy(ubi_class);
1251 ubi_err("UBI error: cannot initialize UBI, error %d", err);
1254 module_init(ubi_init);
1256 static void __exit ubi_exit(void)
1260 for (i = 0; i < UBI_MAX_DEVICES; i++)
1261 if (ubi_devices[i]) {
1262 mutex_lock(&ubi_devices_mutex);
1263 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1264 mutex_unlock(&ubi_devices_mutex);
1267 kmem_cache_destroy(ubi_wl_entry_slab);
1268 misc_deregister(&ubi_ctrl_cdev);
1269 class_remove_file(ubi_class, &ubi_version);
1270 class_destroy(ubi_class);
1272 module_exit(ubi_exit);
1275 * bytes_str_to_int - convert a number of bytes string into an integer.
1276 * @str: the string to convert
1278 * This function returns positive resulting integer in case of success and a
1279 * negative error code in case of failure.
1281 static int __init bytes_str_to_int(const char *str)
1284 unsigned long result;
1286 result = simple_strtoul(str, &endp, 0);
1287 if (str == endp || result >= INT_MAX) {
1288 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1300 if (endp[1] == 'i' && endp[2] == 'B')
1305 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1314 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1315 * @val: the parameter value to parse
1318 * This function returns zero in case of success and a negative error code in
1321 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1324 struct mtd_dev_param *p;
1325 char buf[MTD_PARAM_LEN_MAX];
1326 char *pbuf = &buf[0];
1327 char *tokens[2] = {NULL, NULL};
1332 if (mtd_devs == UBI_MAX_DEVICES) {
1333 printk(KERN_ERR "UBI error: too many parameters, max. is %d\n",
1338 len = strnlen(val, MTD_PARAM_LEN_MAX);
1339 if (len == MTD_PARAM_LEN_MAX) {
1340 printk(KERN_ERR "UBI error: parameter \"%s\" is too long, "
1341 "max. is %d\n", val, MTD_PARAM_LEN_MAX);
1346 printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - "
1353 /* Get rid of the final newline */
1354 if (buf[len - 1] == '\n')
1355 buf[len - 1] = '\0';
1357 for (i = 0; i < 2; i++)
1358 tokens[i] = strsep(&pbuf, ",");
1361 printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n",
1366 p = &mtd_dev_param[mtd_devs];
1367 strcpy(&p->name[0], tokens[0]);
1370 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1372 if (p->vid_hdr_offs < 0)
1373 return p->vid_hdr_offs;
1379 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1380 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1381 "mtd=<name|num|path>[,<vid_hdr_offs>].\n"
1382 "Multiple \"mtd\" parameters may be specified.\n"
1383 "MTD devices may be specified by their number, name, or "
1384 "path to the MTD character device node.\n"
1385 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1386 "header position to be used by UBI.\n"
1387 "Example 1: mtd=/dev/mtd0 - attach MTD device "
1389 "Example 2: mtd=content,1984 mtd=4 - attach MTD device "
1390 "with name \"content\" using VID header offset 1984, and "
1391 "MTD device number 4 with default VID header offset.");
1393 MODULE_VERSION(__stringify(UBI_VERSION));
1394 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1395 MODULE_AUTHOR("Artem Bityutskiy");
1396 MODULE_LICENSE("GPL");