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".
31 * At the moment we only attach UBI devices by scanning, which will become a
32 * bottleneck when flashes reach certain large size. Then one may improve UBI
33 * and add other methods, although it does not seem to be easy to do.
36 #include <linux/err.h>
37 #include <linux/module.h>
38 #include <linux/moduleparam.h>
39 #include <linux/stringify.h>
40 #include <linux/stat.h>
41 #include <linux/miscdevice.h>
42 #include <linux/log2.h>
43 #include <linux/kthread.h>
46 /* Maximum length of the 'mtd=' parameter */
47 #define MTD_PARAM_LEN_MAX 64
50 * struct mtd_dev_param - MTD device parameter description data structure.
51 * @name: MTD device name or number string
52 * @vid_hdr_offs: VID header offset
54 struct mtd_dev_param {
55 char name[MTD_PARAM_LEN_MAX];
59 /* Numbers of elements set in the @mtd_dev_param array */
62 /* MTD devices specification parameters */
63 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
65 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
66 struct class *ubi_class;
68 /* Slab cache for wear-leveling entries */
69 struct kmem_cache *ubi_wl_entry_slab;
71 /* UBI control character device */
72 static struct miscdevice ubi_ctrl_cdev = {
73 .minor = MISC_DYNAMIC_MINOR,
75 .fops = &ubi_ctrl_cdev_operations,
78 /* All UBI devices in system */
79 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
81 /* Serializes UBI devices creations and removals */
82 DEFINE_MUTEX(ubi_devices_mutex);
84 /* Protects @ubi_devices and @ubi->ref_count */
85 static DEFINE_SPINLOCK(ubi_devices_lock);
87 /* "Show" method for files in '/<sysfs>/class/ubi/' */
88 static ssize_t ubi_version_show(struct class *class, char *buf)
90 return sprintf(buf, "%d\n", UBI_VERSION);
93 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
94 static struct class_attribute ubi_version =
95 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
97 static ssize_t dev_attribute_show(struct device *dev,
98 struct device_attribute *attr, char *buf);
100 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
101 static struct device_attribute dev_eraseblock_size =
102 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
103 static struct device_attribute dev_avail_eraseblocks =
104 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
105 static struct device_attribute dev_total_eraseblocks =
106 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
107 static struct device_attribute dev_volumes_count =
108 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
109 static struct device_attribute dev_max_ec =
110 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
111 static struct device_attribute dev_reserved_for_bad =
112 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
113 static struct device_attribute dev_bad_peb_count =
114 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
115 static struct device_attribute dev_max_vol_count =
116 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
117 static struct device_attribute dev_min_io_size =
118 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
119 static struct device_attribute dev_bgt_enabled =
120 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
121 static struct device_attribute dev_mtd_num =
122 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
125 * ubi_volume_notify - send a volume change notification.
126 * @ubi: UBI device description object
127 * @vol: volume description object of the changed volume
128 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
130 * This is a helper function which notifies all subscribers about a volume
131 * change event (creation, removal, re-sizing, re-naming, updating). Returns
132 * zero in case of success and a negative error code in case of failure.
134 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
136 struct ubi_notification nt;
138 ubi_do_get_device_info(ubi, &nt.di);
139 ubi_do_get_volume_info(ubi, vol, &nt.vi);
140 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
144 * ubi_notify_all - send a notification to all volumes.
145 * @ubi: UBI device description object
146 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
147 * @nb: the notifier to call
149 * This function walks all volumes of UBI device @ubi and sends the @ntype
150 * notification for each volume. If @nb is %NULL, then all registered notifiers
151 * are called, otherwise only the @nb notifier is called. Returns the number of
152 * sent notifications.
154 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
156 struct ubi_notification nt;
159 ubi_do_get_device_info(ubi, &nt.di);
161 mutex_lock(&ubi->device_mutex);
162 for (i = 0; i < ubi->vtbl_slots; i++) {
164 * Since the @ubi->device is locked, and we are not going to
165 * change @ubi->volumes, we do not have to lock
166 * @ubi->volumes_lock.
168 if (!ubi->volumes[i])
171 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
173 nb->notifier_call(nb, ntype, &nt);
175 blocking_notifier_call_chain(&ubi_notifiers, ntype,
179 mutex_unlock(&ubi->device_mutex);
185 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
186 * @nb: the notifier to call
188 * This function walks all UBI devices and volumes and sends the
189 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
190 * registered notifiers are called, otherwise only the @nb notifier is called.
191 * Returns the number of sent notifications.
193 int ubi_enumerate_volumes(struct notifier_block *nb)
198 * Since the @ubi_devices_mutex is locked, and we are not going to
199 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
201 for (i = 0; i < UBI_MAX_DEVICES; i++) {
202 struct ubi_device *ubi = ubi_devices[i];
206 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
213 * ubi_get_device - get UBI device.
214 * @ubi_num: UBI device number
216 * This function returns UBI device description object for UBI device number
217 * @ubi_num, or %NULL if the device does not exist. This function increases the
218 * device reference count to prevent removal of the device. In other words, the
219 * device cannot be removed if its reference count is not zero.
221 struct ubi_device *ubi_get_device(int ubi_num)
223 struct ubi_device *ubi;
225 spin_lock(&ubi_devices_lock);
226 ubi = ubi_devices[ubi_num];
228 ubi_assert(ubi->ref_count >= 0);
230 get_device(&ubi->dev);
232 spin_unlock(&ubi_devices_lock);
238 * ubi_put_device - drop an UBI device reference.
239 * @ubi: UBI device description object
241 void ubi_put_device(struct ubi_device *ubi)
243 spin_lock(&ubi_devices_lock);
245 put_device(&ubi->dev);
246 spin_unlock(&ubi_devices_lock);
250 * ubi_get_by_major - get UBI device by character device major number.
251 * @major: major number
253 * This function is similar to 'ubi_get_device()', but it searches the device
254 * by its major number.
256 struct ubi_device *ubi_get_by_major(int major)
259 struct ubi_device *ubi;
261 spin_lock(&ubi_devices_lock);
262 for (i = 0; i < UBI_MAX_DEVICES; i++) {
263 ubi = ubi_devices[i];
264 if (ubi && MAJOR(ubi->cdev.dev) == major) {
265 ubi_assert(ubi->ref_count >= 0);
267 get_device(&ubi->dev);
268 spin_unlock(&ubi_devices_lock);
272 spin_unlock(&ubi_devices_lock);
278 * ubi_major2num - get UBI device number by character device major number.
279 * @major: major number
281 * This function searches UBI device number object by its major number. If UBI
282 * device was not found, this function returns -ENODEV, otherwise the UBI device
283 * number is returned.
285 int ubi_major2num(int major)
287 int i, ubi_num = -ENODEV;
289 spin_lock(&ubi_devices_lock);
290 for (i = 0; i < UBI_MAX_DEVICES; i++) {
291 struct ubi_device *ubi = ubi_devices[i];
293 if (ubi && MAJOR(ubi->cdev.dev) == major) {
294 ubi_num = ubi->ubi_num;
298 spin_unlock(&ubi_devices_lock);
303 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
304 static ssize_t dev_attribute_show(struct device *dev,
305 struct device_attribute *attr, char *buf)
308 struct ubi_device *ubi;
311 * The below code looks weird, but it actually makes sense. We get the
312 * UBI device reference from the contained 'struct ubi_device'. But it
313 * is unclear if the device was removed or not yet. Indeed, if the
314 * device was removed before we increased its reference count,
315 * 'ubi_get_device()' will return -ENODEV and we fail.
317 * Remember, 'struct ubi_device' is freed in the release function, so
318 * we still can use 'ubi->ubi_num'.
320 ubi = container_of(dev, struct ubi_device, dev);
321 ubi = ubi_get_device(ubi->ubi_num);
325 if (attr == &dev_eraseblock_size)
326 ret = sprintf(buf, "%d\n", ubi->leb_size);
327 else if (attr == &dev_avail_eraseblocks)
328 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
329 else if (attr == &dev_total_eraseblocks)
330 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
331 else if (attr == &dev_volumes_count)
332 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
333 else if (attr == &dev_max_ec)
334 ret = sprintf(buf, "%d\n", ubi->max_ec);
335 else if (attr == &dev_reserved_for_bad)
336 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
337 else if (attr == &dev_bad_peb_count)
338 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
339 else if (attr == &dev_max_vol_count)
340 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
341 else if (attr == &dev_min_io_size)
342 ret = sprintf(buf, "%d\n", ubi->min_io_size);
343 else if (attr == &dev_bgt_enabled)
344 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
345 else if (attr == &dev_mtd_num)
346 ret = sprintf(buf, "%d\n", ubi->mtd->index);
354 static void dev_release(struct device *dev)
356 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
362 * ubi_sysfs_init - initialize sysfs for an UBI device.
363 * @ubi: UBI device description object
365 * This function returns zero in case of success and a negative error code in
368 static int ubi_sysfs_init(struct ubi_device *ubi)
372 ubi->dev.release = dev_release;
373 ubi->dev.devt = ubi->cdev.dev;
374 ubi->dev.class = ubi_class;
375 sprintf(&ubi->dev.bus_id[0], UBI_NAME_STR"%d", ubi->ubi_num);
376 err = device_register(&ubi->dev);
380 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
383 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
386 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
389 err = device_create_file(&ubi->dev, &dev_volumes_count);
392 err = device_create_file(&ubi->dev, &dev_max_ec);
395 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
398 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
401 err = device_create_file(&ubi->dev, &dev_max_vol_count);
404 err = device_create_file(&ubi->dev, &dev_min_io_size);
407 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
410 err = device_create_file(&ubi->dev, &dev_mtd_num);
415 * ubi_sysfs_close - close sysfs for an UBI device.
416 * @ubi: UBI device description object
418 static void ubi_sysfs_close(struct ubi_device *ubi)
420 device_remove_file(&ubi->dev, &dev_mtd_num);
421 device_remove_file(&ubi->dev, &dev_bgt_enabled);
422 device_remove_file(&ubi->dev, &dev_min_io_size);
423 device_remove_file(&ubi->dev, &dev_max_vol_count);
424 device_remove_file(&ubi->dev, &dev_bad_peb_count);
425 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
426 device_remove_file(&ubi->dev, &dev_max_ec);
427 device_remove_file(&ubi->dev, &dev_volumes_count);
428 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
429 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
430 device_remove_file(&ubi->dev, &dev_eraseblock_size);
431 device_unregister(&ubi->dev);
435 * kill_volumes - destroy all volumes.
436 * @ubi: UBI device description object
438 static void kill_volumes(struct ubi_device *ubi)
442 for (i = 0; i < ubi->vtbl_slots; i++)
444 ubi_free_volume(ubi, ubi->volumes[i]);
448 * free_user_volumes - free all user volumes.
449 * @ubi: UBI device description object
451 * Normally the volumes are freed at the release function of the volume device
452 * objects. However, on error paths the volumes have to be freed before the
453 * device objects have been initialized.
455 static void free_user_volumes(struct ubi_device *ubi)
459 for (i = 0; i < ubi->vtbl_slots; i++)
460 if (ubi->volumes[i]) {
461 kfree(ubi->volumes[i]->eba_tbl);
462 kfree(ubi->volumes[i]);
467 * uif_init - initialize user interfaces for an UBI device.
468 * @ubi: UBI device description object
470 * This function returns zero in case of success and a negative error code in
471 * case of failure. Note, this function destroys all volumes if it fails.
473 static int uif_init(struct ubi_device *ubi)
478 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
481 * Major numbers for the UBI character devices are allocated
482 * dynamically. Major numbers of volume character devices are
483 * equivalent to ones of the corresponding UBI character device. Minor
484 * numbers of UBI character devices are 0, while minor numbers of
485 * volume character devices start from 1. Thus, we allocate one major
486 * number and ubi->vtbl_slots + 1 minor numbers.
488 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
490 ubi_err("cannot register UBI character devices");
494 ubi_assert(MINOR(dev) == 0);
495 cdev_init(&ubi->cdev, &ubi_cdev_operations);
496 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
497 ubi->cdev.owner = THIS_MODULE;
499 err = cdev_add(&ubi->cdev, dev, 1);
501 ubi_err("cannot add character device");
505 err = ubi_sysfs_init(ubi);
509 for (i = 0; i < ubi->vtbl_slots; i++)
510 if (ubi->volumes[i]) {
511 err = ubi_add_volume(ubi, ubi->volumes[i]);
513 ubi_err("cannot add volume %d", i);
523 ubi_sysfs_close(ubi);
524 cdev_del(&ubi->cdev);
526 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
527 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
532 * uif_close - close user interfaces for an UBI device.
533 * @ubi: UBI device description object
535 * Note, since this function un-registers UBI volume device objects (@vol->dev),
536 * the memory allocated voe the volumes is freed as well (in the release
539 static void uif_close(struct ubi_device *ubi)
542 ubi_sysfs_close(ubi);
543 cdev_del(&ubi->cdev);
544 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
548 * free_internal_volumes - free internal volumes.
549 * @ubi: UBI device description object
551 static void free_internal_volumes(struct ubi_device *ubi)
555 for (i = ubi->vtbl_slots;
556 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
557 kfree(ubi->volumes[i]->eba_tbl);
558 kfree(ubi->volumes[i]);
563 * attach_by_scanning - attach an MTD device using scanning method.
564 * @ubi: UBI device descriptor
566 * This function returns zero in case of success and a negative error code in
569 * Note, currently this is the only method to attach UBI devices. Hopefully in
570 * the future we'll have more scalable attaching methods and avoid full media
571 * scanning. But even in this case scanning will be needed as a fall-back
572 * attaching method if there are some on-flash table corruptions.
574 static int attach_by_scanning(struct ubi_device *ubi)
577 struct ubi_scan_info *si;
583 ubi->bad_peb_count = si->bad_peb_count;
584 ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
585 ubi->max_ec = si->max_ec;
586 ubi->mean_ec = si->mean_ec;
588 err = ubi_read_volume_table(ubi, si);
592 err = ubi_wl_init_scan(ubi, si);
596 err = ubi_eba_init_scan(ubi, si);
600 ubi_scan_destroy_si(si);
606 free_internal_volumes(ubi);
609 ubi_scan_destroy_si(si);
614 * io_init - initialize I/O sub-system for a given UBI device.
615 * @ubi: UBI device description object
617 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
619 * o EC header is always at offset zero - this cannot be changed;
620 * o VID header starts just after the EC header at the closest address
621 * aligned to @io->hdrs_min_io_size;
622 * o data starts just after the VID header at the closest address aligned to
625 * This function returns zero in case of success and a negative error code in
628 static int io_init(struct ubi_device *ubi)
630 if (ubi->mtd->numeraseregions != 0) {
632 * Some flashes have several erase regions. Different regions
633 * may have different eraseblock size and other
634 * characteristics. It looks like mostly multi-region flashes
635 * have one "main" region and one or more small regions to
636 * store boot loader code or boot parameters or whatever. I
637 * guess we should just pick the largest region. But this is
640 ubi_err("multiple regions, not implemented");
644 if (ubi->vid_hdr_offset < 0)
648 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
649 * physical eraseblocks maximum.
652 ubi->peb_size = ubi->mtd->erasesize;
653 ubi->peb_count = ubi->mtd->size / ubi->mtd->erasesize;
654 ubi->flash_size = ubi->mtd->size;
656 if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
657 ubi->bad_allowed = 1;
659 ubi->min_io_size = ubi->mtd->writesize;
660 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
663 * Make sure minimal I/O unit is power of 2. Note, there is no
664 * fundamental reason for this assumption. It is just an optimization
665 * which allows us to avoid costly division operations.
667 if (!is_power_of_2(ubi->min_io_size)) {
668 ubi_err("min. I/O unit (%d) is not power of 2",
673 ubi_assert(ubi->hdrs_min_io_size > 0);
674 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
675 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
677 /* Calculate default aligned sizes of EC and VID headers */
678 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
679 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
681 dbg_msg("min_io_size %d", ubi->min_io_size);
682 dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
683 dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
684 dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
686 if (ubi->vid_hdr_offset == 0)
688 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
691 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
692 ~(ubi->hdrs_min_io_size - 1);
693 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
694 ubi->vid_hdr_aloffset;
697 /* Similar for the data offset */
698 ubi->leb_start = ubi->vid_hdr_offset + UBI_EC_HDR_SIZE;
699 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
701 dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
702 dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
703 dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
704 dbg_msg("leb_start %d", ubi->leb_start);
706 /* The shift must be aligned to 32-bit boundary */
707 if (ubi->vid_hdr_shift % 4) {
708 ubi_err("unaligned VID header shift %d",
714 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
715 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
716 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
717 ubi->leb_start & (ubi->min_io_size - 1)) {
718 ubi_err("bad VID header (%d) or data offsets (%d)",
719 ubi->vid_hdr_offset, ubi->leb_start);
724 * Set maximum amount of physical erroneous eraseblocks to be 10%.
725 * Erroneous PEB are those which have read errors.
727 ubi->max_erroneous = ubi->peb_count / 10;
728 if (ubi->max_erroneous < 16)
729 ubi->max_erroneous = 16;
730 dbg_msg("max_erroneous %d", ubi->max_erroneous);
733 * It may happen that EC and VID headers are situated in one minimal
734 * I/O unit. In this case we can only accept this UBI image in
737 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
738 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
739 "switch to read-only mode");
743 ubi->leb_size = ubi->peb_size - ubi->leb_start;
745 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
746 ubi_msg("MTD device %d is write-protected, attach in "
747 "read-only mode", ubi->mtd->index);
751 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
752 ubi->peb_size, ubi->peb_size >> 10);
753 ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
754 ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
755 if (ubi->hdrs_min_io_size != ubi->min_io_size)
756 ubi_msg("sub-page size: %d",
757 ubi->hdrs_min_io_size);
758 ubi_msg("VID header offset: %d (aligned %d)",
759 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
760 ubi_msg("data offset: %d", ubi->leb_start);
763 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
764 * unfortunately, MTD does not provide this information. We should loop
765 * over all physical eraseblocks and invoke mtd->block_is_bad() for
766 * each physical eraseblock. So, we skip ubi->bad_peb_count
767 * uninitialized and initialize it after scanning.
774 * autoresize - re-size the volume which has the "auto-resize" flag set.
775 * @ubi: UBI device description object
776 * @vol_id: ID of the volume to re-size
778 * This function re-sizes the volume marked by the @UBI_VTBL_AUTORESIZE_FLG in
779 * the volume table to the largest possible size. See comments in ubi-header.h
780 * for more description of the flag. Returns zero in case of success and a
781 * negative error code in case of failure.
783 static int autoresize(struct ubi_device *ubi, int vol_id)
785 struct ubi_volume_desc desc;
786 struct ubi_volume *vol = ubi->volumes[vol_id];
787 int err, old_reserved_pebs = vol->reserved_pebs;
790 * Clear the auto-resize flag in the volume in-memory copy of the
791 * volume table, and 'ubi_resize_volume()' will propagate this change
794 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
796 if (ubi->avail_pebs == 0) {
797 struct ubi_vtbl_record vtbl_rec;
800 * No available PEBs to re-size the volume, clear the flag on
803 memcpy(&vtbl_rec, &ubi->vtbl[vol_id],
804 sizeof(struct ubi_vtbl_record));
805 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
807 ubi_err("cannot clean auto-resize flag for volume %d",
811 err = ubi_resize_volume(&desc,
812 old_reserved_pebs + ubi->avail_pebs);
814 ubi_err("cannot auto-resize volume %d", vol_id);
820 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
821 vol->name, old_reserved_pebs, vol->reserved_pebs);
826 * ubi_attach_mtd_dev - attach an MTD device.
827 * @mtd: MTD device description object
828 * @ubi_num: number to assign to the new UBI device
829 * @vid_hdr_offset: VID header offset
831 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
832 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
833 * which case this function finds a vacant device number and assigns it
834 * automatically. Returns the new UBI device number in case of success and a
835 * negative error code in case of failure.
837 * Note, the invocations of this function has to be serialized by the
838 * @ubi_devices_mutex.
840 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
842 struct ubi_device *ubi;
843 int i, err, do_free = 1;
846 * Check if we already have the same MTD device attached.
848 * Note, this function assumes that UBI devices creations and deletions
849 * are serialized, so it does not take the &ubi_devices_lock.
851 for (i = 0; i < UBI_MAX_DEVICES; i++) {
852 ubi = ubi_devices[i];
853 if (ubi && mtd->index == ubi->mtd->index) {
854 dbg_err("mtd%d is already attached to ubi%d",
861 * Make sure this MTD device is not emulated on top of an UBI volume
862 * already. Well, generally this recursion works fine, but there are
863 * different problems like the UBI module takes a reference to itself
864 * by attaching (and thus, opening) the emulated MTD device. This
865 * results in inability to unload the module. And in general it makes
866 * no sense to attach emulated MTD devices, so we prohibit this.
868 if (mtd->type == MTD_UBIVOLUME) {
869 ubi_err("refuse attaching mtd%d - it is already emulated on "
870 "top of UBI", mtd->index);
874 if (ubi_num == UBI_DEV_NUM_AUTO) {
875 /* Search for an empty slot in the @ubi_devices array */
876 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
877 if (!ubi_devices[ubi_num])
879 if (ubi_num == UBI_MAX_DEVICES) {
880 dbg_err("only %d UBI devices may be created",
885 if (ubi_num >= UBI_MAX_DEVICES)
888 /* Make sure ubi_num is not busy */
889 if (ubi_devices[ubi_num]) {
890 dbg_err("ubi%d already exists", ubi_num);
895 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
900 ubi->ubi_num = ubi_num;
901 ubi->vid_hdr_offset = vid_hdr_offset;
902 ubi->autoresize_vol_id = -1;
904 mutex_init(&ubi->buf_mutex);
905 mutex_init(&ubi->ckvol_mutex);
906 mutex_init(&ubi->device_mutex);
907 spin_lock_init(&ubi->volumes_lock);
909 ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
916 ubi->peb_buf1 = vmalloc(ubi->peb_size);
920 ubi->peb_buf2 = vmalloc(ubi->peb_size);
924 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
925 mutex_init(&ubi->dbg_buf_mutex);
926 ubi->dbg_peb_buf = vmalloc(ubi->peb_size);
927 if (!ubi->dbg_peb_buf)
931 err = attach_by_scanning(ubi);
933 dbg_err("failed to attach by scanning, error %d", err);
937 if (ubi->autoresize_vol_id != -1) {
938 err = autoresize(ubi, ubi->autoresize_vol_id);
947 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
948 if (IS_ERR(ubi->bgt_thread)) {
949 err = PTR_ERR(ubi->bgt_thread);
950 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
955 ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num);
956 ubi_msg("MTD device name: \"%s\"", mtd->name);
957 ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
958 ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
959 ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
960 ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
961 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
962 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
963 ubi_msg("number of user volumes: %d",
964 ubi->vol_count - UBI_INT_VOL_COUNT);
965 ubi_msg("available PEBs: %d", ubi->avail_pebs);
966 ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
967 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
969 ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
972 * The below lock makes sure we do not race with 'ubi_thread()' which
973 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
975 spin_lock(&ubi->wl_lock);
976 if (!DBG_DISABLE_BGT)
977 ubi->thread_enabled = 1;
978 wake_up_process(ubi->bgt_thread);
979 spin_unlock(&ubi->wl_lock);
981 ubi_devices[ubi_num] = ubi;
982 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
992 free_user_volumes(ubi);
993 free_internal_volumes(ubi);
996 vfree(ubi->peb_buf1);
997 vfree(ubi->peb_buf2);
998 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
999 vfree(ubi->dbg_peb_buf);
1006 * ubi_detach_mtd_dev - detach an MTD device.
1007 * @ubi_num: UBI device number to detach from
1008 * @anyway: detach MTD even if device reference count is not zero
1010 * This function destroys an UBI device number @ubi_num and detaches the
1011 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1012 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1015 * Note, the invocations of this function has to be serialized by the
1016 * @ubi_devices_mutex.
1018 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1020 struct ubi_device *ubi;
1022 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1025 ubi = ubi_get_device(ubi_num);
1029 spin_lock(&ubi_devices_lock);
1030 put_device(&ubi->dev);
1031 ubi->ref_count -= 1;
1032 if (ubi->ref_count) {
1034 spin_unlock(&ubi_devices_lock);
1037 /* This may only happen if there is a bug */
1038 ubi_err("%s reference count %d, destroy anyway",
1039 ubi->ubi_name, ubi->ref_count);
1041 ubi_devices[ubi_num] = NULL;
1042 spin_unlock(&ubi_devices_lock);
1044 ubi_assert(ubi_num == ubi->ubi_num);
1045 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1046 dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1049 * Before freeing anything, we have to stop the background thread to
1050 * prevent it from doing anything on this device while we are freeing.
1052 if (ubi->bgt_thread)
1053 kthread_stop(ubi->bgt_thread);
1056 * Get a reference to the device in order to prevent 'dev_release()'
1057 * from freeing @ubi object.
1059 get_device(&ubi->dev);
1063 free_internal_volumes(ubi);
1065 put_mtd_device(ubi->mtd);
1066 vfree(ubi->peb_buf1);
1067 vfree(ubi->peb_buf2);
1068 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1069 vfree(ubi->dbg_peb_buf);
1071 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1072 put_device(&ubi->dev);
1077 * find_mtd_device - open an MTD device by its name or number.
1078 * @mtd_dev: name or number of the device
1080 * This function tries to open and MTD device described by @mtd_dev string,
1081 * which is first treated as an ASCII number, and if it is not true, it is
1082 * treated as MTD device name. Returns MTD device description object in case of
1083 * success and a negative error code in case of failure.
1085 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1087 struct mtd_info *mtd;
1091 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1092 if (*endp != '\0' || mtd_dev == endp) {
1094 * This does not look like an ASCII integer, probably this is
1097 mtd = get_mtd_device_nm(mtd_dev);
1099 mtd = get_mtd_device(NULL, mtd_num);
1104 static int __init ubi_init(void)
1108 /* Ensure that EC and VID headers have correct size */
1109 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1110 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1112 if (mtd_devs > UBI_MAX_DEVICES) {
1113 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1117 /* Create base sysfs directory and sysfs files */
1118 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1119 if (IS_ERR(ubi_class)) {
1120 err = PTR_ERR(ubi_class);
1121 ubi_err("cannot create UBI class");
1125 err = class_create_file(ubi_class, &ubi_version);
1127 ubi_err("cannot create sysfs file");
1131 err = misc_register(&ubi_ctrl_cdev);
1133 ubi_err("cannot register device");
1137 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1138 sizeof(struct ubi_wl_entry),
1140 if (!ubi_wl_entry_slab)
1143 /* Attach MTD devices */
1144 for (i = 0; i < mtd_devs; i++) {
1145 struct mtd_dev_param *p = &mtd_dev_param[i];
1146 struct mtd_info *mtd;
1150 mtd = open_mtd_device(p->name);
1156 mutex_lock(&ubi_devices_mutex);
1157 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
1159 mutex_unlock(&ubi_devices_mutex);
1161 put_mtd_device(mtd);
1162 ubi_err("cannot attach mtd%d", mtd->index);
1170 for (k = 0; k < i; k++)
1171 if (ubi_devices[k]) {
1172 mutex_lock(&ubi_devices_mutex);
1173 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1174 mutex_unlock(&ubi_devices_mutex);
1176 kmem_cache_destroy(ubi_wl_entry_slab);
1178 misc_deregister(&ubi_ctrl_cdev);
1180 class_remove_file(ubi_class, &ubi_version);
1182 class_destroy(ubi_class);
1184 ubi_err("UBI error: cannot initialize UBI, error %d", err);
1187 module_init(ubi_init);
1189 static void __exit ubi_exit(void)
1193 for (i = 0; i < UBI_MAX_DEVICES; i++)
1194 if (ubi_devices[i]) {
1195 mutex_lock(&ubi_devices_mutex);
1196 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1197 mutex_unlock(&ubi_devices_mutex);
1199 kmem_cache_destroy(ubi_wl_entry_slab);
1200 misc_deregister(&ubi_ctrl_cdev);
1201 class_remove_file(ubi_class, &ubi_version);
1202 class_destroy(ubi_class);
1204 module_exit(ubi_exit);
1207 * bytes_str_to_int - convert a number of bytes string into an integer.
1208 * @str: the string to convert
1210 * This function returns positive resulting integer in case of success and a
1211 * negative error code in case of failure.
1213 static int __init bytes_str_to_int(const char *str)
1216 unsigned long result;
1218 result = simple_strtoul(str, &endp, 0);
1219 if (str == endp || result < 0) {
1220 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1232 if (endp[1] == 'i' && endp[2] == 'B')
1237 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1246 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1247 * @val: the parameter value to parse
1250 * This function returns zero in case of success and a negative error code in
1253 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1256 struct mtd_dev_param *p;
1257 char buf[MTD_PARAM_LEN_MAX];
1258 char *pbuf = &buf[0];
1259 char *tokens[2] = {NULL, NULL};
1264 if (mtd_devs == UBI_MAX_DEVICES) {
1265 printk(KERN_ERR "UBI error: too many parameters, max. is %d\n",
1270 len = strnlen(val, MTD_PARAM_LEN_MAX);
1271 if (len == MTD_PARAM_LEN_MAX) {
1272 printk(KERN_ERR "UBI error: parameter \"%s\" is too long, "
1273 "max. is %d\n", val, MTD_PARAM_LEN_MAX);
1278 printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - "
1285 /* Get rid of the final newline */
1286 if (buf[len - 1] == '\n')
1287 buf[len - 1] = '\0';
1289 for (i = 0; i < 2; i++)
1290 tokens[i] = strsep(&pbuf, ",");
1293 printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n",
1298 p = &mtd_dev_param[mtd_devs];
1299 strcpy(&p->name[0], tokens[0]);
1302 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1304 if (p->vid_hdr_offs < 0)
1305 return p->vid_hdr_offs;
1311 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1312 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1313 "mtd=<name|num>[,<vid_hdr_offs>].\n"
1314 "Multiple \"mtd\" parameters may be specified.\n"
1315 "MTD devices may be specified by their number or name.\n"
1316 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1317 "header position and data starting position to be used "
1319 "Example: mtd=content,1984 mtd=4 - attach MTD device"
1320 "with name \"content\" using VID header offset 1984, and "
1321 "MTD device number 4 with default VID header offset.");
1323 MODULE_VERSION(__stringify(UBI_VERSION));
1324 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1325 MODULE_AUTHOR("Artem Bityutskiy");
1326 MODULE_LICENSE("GPL");