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/log2.h>
40 #include <linux/kthread.h>
41 #include <linux/kernel.h>
42 #include <linux/slab.h>
45 /* Maximum length of the 'mtd=' parameter */
46 #define MTD_PARAM_LEN_MAX 64
48 #ifdef CONFIG_MTD_UBI_MODULE
49 #define ubi_is_module() 1
51 #define ubi_is_module() 0
55 * struct mtd_dev_param - MTD device parameter description data structure.
56 * @name: MTD character device node path, MTD device name, or MTD device number
58 * @vid_hdr_offs: VID header offset
60 struct mtd_dev_param {
61 char name[MTD_PARAM_LEN_MAX];
65 /* Numbers of elements set in the @mtd_dev_param array */
66 static int __initdata mtd_devs;
68 /* MTD devices specification parameters */
69 static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES];
71 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
72 struct class *ubi_class;
74 /* Slab cache for wear-leveling entries */
75 struct kmem_cache *ubi_wl_entry_slab;
77 /* UBI control character device */
78 static struct miscdevice ubi_ctrl_cdev = {
79 .minor = MISC_DYNAMIC_MINOR,
81 .fops = &ubi_ctrl_cdev_operations,
84 /* All UBI devices in system */
85 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
87 /* Serializes UBI devices creations and removals */
88 DEFINE_MUTEX(ubi_devices_mutex);
90 /* Protects @ubi_devices and @ubi->ref_count */
91 static DEFINE_SPINLOCK(ubi_devices_lock);
93 /* "Show" method for files in '/<sysfs>/class/ubi/' */
94 static ssize_t ubi_version_show(struct class *class,
95 struct class_attribute *attr, char *buf)
97 return sprintf(buf, "%d\n", UBI_VERSION);
100 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
101 static struct class_attribute ubi_version =
102 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
104 static ssize_t dev_attribute_show(struct device *dev,
105 struct device_attribute *attr, char *buf);
107 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
108 static struct device_attribute dev_eraseblock_size =
109 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
110 static struct device_attribute dev_avail_eraseblocks =
111 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
112 static struct device_attribute dev_total_eraseblocks =
113 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
114 static struct device_attribute dev_volumes_count =
115 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
116 static struct device_attribute dev_max_ec =
117 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
118 static struct device_attribute dev_reserved_for_bad =
119 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
120 static struct device_attribute dev_bad_peb_count =
121 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
122 static struct device_attribute dev_max_vol_count =
123 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
124 static struct device_attribute dev_min_io_size =
125 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
126 static struct device_attribute dev_bgt_enabled =
127 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
128 static struct device_attribute dev_mtd_num =
129 __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
132 * ubi_volume_notify - send a volume change notification.
133 * @ubi: UBI device description object
134 * @vol: volume description object of the changed volume
135 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
137 * This is a helper function which notifies all subscribers about a volume
138 * change event (creation, removal, re-sizing, re-naming, updating). Returns
139 * zero in case of success and a negative error code in case of failure.
141 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
143 struct ubi_notification nt;
145 ubi_do_get_device_info(ubi, &nt.di);
146 ubi_do_get_volume_info(ubi, vol, &nt.vi);
147 return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
151 * ubi_notify_all - send a notification to all volumes.
152 * @ubi: UBI device description object
153 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
154 * @nb: the notifier to call
156 * This function walks all volumes of UBI device @ubi and sends the @ntype
157 * notification for each volume. If @nb is %NULL, then all registered notifiers
158 * are called, otherwise only the @nb notifier is called. Returns the number of
159 * sent notifications.
161 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
163 struct ubi_notification nt;
166 ubi_do_get_device_info(ubi, &nt.di);
168 mutex_lock(&ubi->device_mutex);
169 for (i = 0; i < ubi->vtbl_slots; i++) {
171 * Since the @ubi->device is locked, and we are not going to
172 * change @ubi->volumes, we do not have to lock
173 * @ubi->volumes_lock.
175 if (!ubi->volumes[i])
178 ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
180 nb->notifier_call(nb, ntype, &nt);
182 blocking_notifier_call_chain(&ubi_notifiers, ntype,
186 mutex_unlock(&ubi->device_mutex);
192 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
193 * @nb: the notifier to call
195 * This function walks all UBI devices and volumes and sends the
196 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
197 * registered notifiers are called, otherwise only the @nb notifier is called.
198 * Returns the number of sent notifications.
200 int ubi_enumerate_volumes(struct notifier_block *nb)
205 * Since the @ubi_devices_mutex is locked, and we are not going to
206 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
208 for (i = 0; i < UBI_MAX_DEVICES; i++) {
209 struct ubi_device *ubi = ubi_devices[i];
213 count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
220 * ubi_get_device - get UBI device.
221 * @ubi_num: UBI device number
223 * This function returns UBI device description object for UBI device number
224 * @ubi_num, or %NULL if the device does not exist. This function increases the
225 * device reference count to prevent removal of the device. In other words, the
226 * device cannot be removed if its reference count is not zero.
228 struct ubi_device *ubi_get_device(int ubi_num)
230 struct ubi_device *ubi;
232 spin_lock(&ubi_devices_lock);
233 ubi = ubi_devices[ubi_num];
235 ubi_assert(ubi->ref_count >= 0);
237 get_device(&ubi->dev);
239 spin_unlock(&ubi_devices_lock);
245 * ubi_put_device - drop an UBI device reference.
246 * @ubi: UBI device description object
248 void ubi_put_device(struct ubi_device *ubi)
250 spin_lock(&ubi_devices_lock);
252 put_device(&ubi->dev);
253 spin_unlock(&ubi_devices_lock);
257 * ubi_get_by_major - get UBI device by character device major number.
258 * @major: major number
260 * This function is similar to 'ubi_get_device()', but it searches the device
261 * by its major number.
263 struct ubi_device *ubi_get_by_major(int major)
266 struct ubi_device *ubi;
268 spin_lock(&ubi_devices_lock);
269 for (i = 0; i < UBI_MAX_DEVICES; i++) {
270 ubi = ubi_devices[i];
271 if (ubi && MAJOR(ubi->cdev.dev) == major) {
272 ubi_assert(ubi->ref_count >= 0);
274 get_device(&ubi->dev);
275 spin_unlock(&ubi_devices_lock);
279 spin_unlock(&ubi_devices_lock);
285 * ubi_major2num - get UBI device number by character device major number.
286 * @major: major number
288 * This function searches UBI device number object by its major number. If UBI
289 * device was not found, this function returns -ENODEV, otherwise the UBI device
290 * number is returned.
292 int ubi_major2num(int major)
294 int i, ubi_num = -ENODEV;
296 spin_lock(&ubi_devices_lock);
297 for (i = 0; i < UBI_MAX_DEVICES; i++) {
298 struct ubi_device *ubi = ubi_devices[i];
300 if (ubi && MAJOR(ubi->cdev.dev) == major) {
301 ubi_num = ubi->ubi_num;
305 spin_unlock(&ubi_devices_lock);
310 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
311 static ssize_t dev_attribute_show(struct device *dev,
312 struct device_attribute *attr, char *buf)
315 struct ubi_device *ubi;
318 * The below code looks weird, but it actually makes sense. We get the
319 * UBI device reference from the contained 'struct ubi_device'. But it
320 * is unclear if the device was removed or not yet. Indeed, if the
321 * device was removed before we increased its reference count,
322 * 'ubi_get_device()' will return -ENODEV and we fail.
324 * Remember, 'struct ubi_device' is freed in the release function, so
325 * we still can use 'ubi->ubi_num'.
327 ubi = container_of(dev, struct ubi_device, dev);
328 ubi = ubi_get_device(ubi->ubi_num);
332 if (attr == &dev_eraseblock_size)
333 ret = sprintf(buf, "%d\n", ubi->leb_size);
334 else if (attr == &dev_avail_eraseblocks)
335 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
336 else if (attr == &dev_total_eraseblocks)
337 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
338 else if (attr == &dev_volumes_count)
339 ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
340 else if (attr == &dev_max_ec)
341 ret = sprintf(buf, "%d\n", ubi->max_ec);
342 else if (attr == &dev_reserved_for_bad)
343 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
344 else if (attr == &dev_bad_peb_count)
345 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
346 else if (attr == &dev_max_vol_count)
347 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
348 else if (attr == &dev_min_io_size)
349 ret = sprintf(buf, "%d\n", ubi->min_io_size);
350 else if (attr == &dev_bgt_enabled)
351 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
352 else if (attr == &dev_mtd_num)
353 ret = sprintf(buf, "%d\n", ubi->mtd->index);
361 static void dev_release(struct device *dev)
363 struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
369 * ubi_sysfs_init - initialize sysfs for an UBI device.
370 * @ubi: UBI device description object
371 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
374 * This function returns zero in case of success and a negative error code in
377 static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
381 ubi->dev.release = dev_release;
382 ubi->dev.devt = ubi->cdev.dev;
383 ubi->dev.class = ubi_class;
384 dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
385 err = device_register(&ubi->dev);
390 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
393 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
396 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
399 err = device_create_file(&ubi->dev, &dev_volumes_count);
402 err = device_create_file(&ubi->dev, &dev_max_ec);
405 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
408 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
411 err = device_create_file(&ubi->dev, &dev_max_vol_count);
414 err = device_create_file(&ubi->dev, &dev_min_io_size);
417 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
420 err = device_create_file(&ubi->dev, &dev_mtd_num);
425 * ubi_sysfs_close - close sysfs for an UBI device.
426 * @ubi: UBI device description object
428 static void ubi_sysfs_close(struct ubi_device *ubi)
430 device_remove_file(&ubi->dev, &dev_mtd_num);
431 device_remove_file(&ubi->dev, &dev_bgt_enabled);
432 device_remove_file(&ubi->dev, &dev_min_io_size);
433 device_remove_file(&ubi->dev, &dev_max_vol_count);
434 device_remove_file(&ubi->dev, &dev_bad_peb_count);
435 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
436 device_remove_file(&ubi->dev, &dev_max_ec);
437 device_remove_file(&ubi->dev, &dev_volumes_count);
438 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
439 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
440 device_remove_file(&ubi->dev, &dev_eraseblock_size);
441 device_unregister(&ubi->dev);
445 * kill_volumes - destroy all user volumes.
446 * @ubi: UBI device description object
448 static void kill_volumes(struct ubi_device *ubi)
452 for (i = 0; i < ubi->vtbl_slots; i++)
454 ubi_free_volume(ubi, ubi->volumes[i]);
458 * uif_init - initialize user interfaces for an UBI device.
459 * @ubi: UBI device description object
460 * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was
461 * taken, otherwise set to %0
463 * This function initializes various user interfaces for an UBI device. If the
464 * initialization fails at an early stage, this function frees all the
465 * resources it allocated, returns an error, and @ref is set to %0. However,
466 * if the initialization fails after the UBI device was registered in the
467 * driver core subsystem, this function takes a reference to @ubi->dev, because
468 * otherwise the release function ('dev_release()') would free whole @ubi
469 * object. The @ref argument is set to %1 in this case. The caller has to put
472 * This function returns zero in case of success and a negative error code in
475 static int uif_init(struct ubi_device *ubi, int *ref)
481 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
484 * Major numbers for the UBI character devices are allocated
485 * dynamically. Major numbers of volume character devices are
486 * equivalent to ones of the corresponding UBI character device. Minor
487 * numbers of UBI character devices are 0, while minor numbers of
488 * volume character devices start from 1. Thus, we allocate one major
489 * number and ubi->vtbl_slots + 1 minor numbers.
491 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
493 ubi_err("cannot register UBI character devices");
497 ubi_assert(MINOR(dev) == 0);
498 cdev_init(&ubi->cdev, &ubi_cdev_operations);
499 dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
500 ubi->cdev.owner = THIS_MODULE;
502 err = cdev_add(&ubi->cdev, dev, 1);
504 ubi_err("cannot add character device");
508 err = ubi_sysfs_init(ubi, ref);
512 for (i = 0; i < ubi->vtbl_slots; i++)
513 if (ubi->volumes[i]) {
514 err = ubi_add_volume(ubi, ubi->volumes[i]);
516 ubi_err("cannot add volume %d", i);
527 get_device(&ubi->dev);
528 ubi_sysfs_close(ubi);
529 cdev_del(&ubi->cdev);
531 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
532 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
537 * uif_close - close user interfaces for an UBI device.
538 * @ubi: UBI device description object
540 * Note, since this function un-registers UBI volume device objects (@vol->dev),
541 * the memory allocated voe the volumes is freed as well (in the release
544 static void uif_close(struct ubi_device *ubi)
547 ubi_sysfs_close(ubi);
548 cdev_del(&ubi->cdev);
549 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
553 * ubi_free_internal_volumes - free internal volumes.
554 * @ubi: UBI device description object
556 void ubi_free_internal_volumes(struct ubi_device *ubi)
560 for (i = ubi->vtbl_slots;
561 i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
562 kfree(ubi->volumes[i]->eba_tbl);
563 kfree(ubi->volumes[i]);
568 * io_init - initialize I/O sub-system for a given UBI device.
569 * @ubi: UBI device description object
571 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
573 * o EC header is always at offset zero - this cannot be changed;
574 * o VID header starts just after the EC header at the closest address
575 * aligned to @io->hdrs_min_io_size;
576 * o data starts just after the VID header at the closest address aligned to
579 * This function returns zero in case of success and a negative error code in
582 static int io_init(struct ubi_device *ubi)
584 dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
585 dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
587 if (ubi->mtd->numeraseregions != 0) {
589 * Some flashes have several erase regions. Different regions
590 * may have different eraseblock size and other
591 * characteristics. It looks like mostly multi-region flashes
592 * have one "main" region and one or more small regions to
593 * store boot loader code or boot parameters or whatever. I
594 * guess we should just pick the largest region. But this is
597 ubi_err("multiple regions, not implemented");
601 if (ubi->vid_hdr_offset < 0)
605 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
606 * physical eraseblocks maximum.
609 ubi->peb_size = ubi->mtd->erasesize;
610 ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
611 ubi->flash_size = ubi->mtd->size;
613 if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
614 ubi->bad_allowed = 1;
616 if (ubi->mtd->type == MTD_NORFLASH) {
617 ubi_assert(ubi->mtd->writesize == 1);
621 ubi->min_io_size = ubi->mtd->writesize;
622 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
625 * Make sure minimal I/O unit is power of 2. Note, there is no
626 * fundamental reason for this assumption. It is just an optimization
627 * which allows us to avoid costly division operations.
629 if (!is_power_of_2(ubi->min_io_size)) {
630 ubi_err("min. I/O unit (%d) is not power of 2",
635 ubi_assert(ubi->hdrs_min_io_size > 0);
636 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
637 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
639 ubi->max_write_size = ubi->mtd->writebufsize;
641 * Maximum write size has to be greater or equivalent to min. I/O
642 * size, and be multiple of min. I/O size.
644 if (ubi->max_write_size < ubi->min_io_size ||
645 ubi->max_write_size % ubi->min_io_size ||
646 !is_power_of_2(ubi->max_write_size)) {
647 ubi_err("bad write buffer size %d for %d min. I/O unit",
648 ubi->max_write_size, ubi->min_io_size);
652 /* Calculate default aligned sizes of EC and VID headers */
653 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
654 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
656 dbg_gen("min_io_size %d", ubi->min_io_size);
657 dbg_gen("max_write_size %d", ubi->max_write_size);
658 dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
659 dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
660 dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
662 if (ubi->vid_hdr_offset == 0)
664 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
667 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
668 ~(ubi->hdrs_min_io_size - 1);
669 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
670 ubi->vid_hdr_aloffset;
673 /* Similar for the data offset */
674 ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
675 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
677 dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
678 dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
679 dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
680 dbg_gen("leb_start %d", ubi->leb_start);
682 /* The shift must be aligned to 32-bit boundary */
683 if (ubi->vid_hdr_shift % 4) {
684 ubi_err("unaligned VID header shift %d",
690 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
691 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
692 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
693 ubi->leb_start & (ubi->min_io_size - 1)) {
694 ubi_err("bad VID header (%d) or data offsets (%d)",
695 ubi->vid_hdr_offset, ubi->leb_start);
700 * Set maximum amount of physical erroneous eraseblocks to be 10%.
701 * Erroneous PEB are those which have read errors.
703 ubi->max_erroneous = ubi->peb_count / 10;
704 if (ubi->max_erroneous < 16)
705 ubi->max_erroneous = 16;
706 dbg_gen("max_erroneous %d", ubi->max_erroneous);
709 * It may happen that EC and VID headers are situated in one minimal
710 * I/O unit. In this case we can only accept this UBI image in
713 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
714 ubi_warn("EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
718 ubi->leb_size = ubi->peb_size - ubi->leb_start;
720 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
721 ubi_msg("MTD device %d is write-protected, attach in read-only mode",
727 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
728 * unfortunately, MTD does not provide this information. We should loop
729 * over all physical eraseblocks and invoke mtd->block_is_bad() for
730 * each physical eraseblock. So, we leave @ubi->bad_peb_count
731 * uninitialized so far.
738 * autoresize - re-size the volume which has the "auto-resize" flag set.
739 * @ubi: UBI device description object
740 * @vol_id: ID of the volume to re-size
742 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
743 * the volume table to the largest possible size. See comments in ubi-header.h
744 * for more description of the flag. Returns zero in case of success and a
745 * negative error code in case of failure.
747 static int autoresize(struct ubi_device *ubi, int vol_id)
749 struct ubi_volume_desc desc;
750 struct ubi_volume *vol = ubi->volumes[vol_id];
751 int err, old_reserved_pebs = vol->reserved_pebs;
754 ubi_warn("skip auto-resize because of R/O mode");
759 * Clear the auto-resize flag in the volume in-memory copy of the
760 * volume table, and 'ubi_resize_volume()' will propagate this change
763 ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
765 if (ubi->avail_pebs == 0) {
766 struct ubi_vtbl_record vtbl_rec;
769 * No available PEBs to re-size the volume, clear the flag on
772 memcpy(&vtbl_rec, &ubi->vtbl[vol_id],
773 sizeof(struct ubi_vtbl_record));
774 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
776 ubi_err("cannot clean auto-resize flag for volume %d",
780 err = ubi_resize_volume(&desc,
781 old_reserved_pebs + ubi->avail_pebs);
783 ubi_err("cannot auto-resize volume %d", vol_id);
789 ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
790 vol->name, old_reserved_pebs, vol->reserved_pebs);
795 * ubi_attach_mtd_dev - attach an MTD device.
796 * @mtd: MTD device description object
797 * @ubi_num: number to assign to the new UBI device
798 * @vid_hdr_offset: VID header offset
800 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
801 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
802 * which case this function finds a vacant device number and assigns it
803 * automatically. Returns the new UBI device number in case of success and a
804 * negative error code in case of failure.
806 * Note, the invocations of this function has to be serialized by the
807 * @ubi_devices_mutex.
809 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
811 struct ubi_device *ubi;
815 * Check if we already have the same MTD device attached.
817 * Note, this function assumes that UBI devices creations and deletions
818 * are serialized, so it does not take the &ubi_devices_lock.
820 for (i = 0; i < UBI_MAX_DEVICES; i++) {
821 ubi = ubi_devices[i];
822 if (ubi && mtd->index == ubi->mtd->index) {
823 ubi_err("mtd%d is already attached to ubi%d",
830 * Make sure this MTD device is not emulated on top of an UBI volume
831 * already. Well, generally this recursion works fine, but there are
832 * different problems like the UBI module takes a reference to itself
833 * by attaching (and thus, opening) the emulated MTD device. This
834 * results in inability to unload the module. And in general it makes
835 * no sense to attach emulated MTD devices, so we prohibit this.
837 if (mtd->type == MTD_UBIVOLUME) {
838 ubi_err("refuse attaching mtd%d - it is already emulated on top of UBI",
843 if (ubi_num == UBI_DEV_NUM_AUTO) {
844 /* Search for an empty slot in the @ubi_devices array */
845 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
846 if (!ubi_devices[ubi_num])
848 if (ubi_num == UBI_MAX_DEVICES) {
849 ubi_err("only %d UBI devices may be created",
854 if (ubi_num >= UBI_MAX_DEVICES)
857 /* Make sure ubi_num is not busy */
858 if (ubi_devices[ubi_num]) {
859 ubi_err("ubi%d already exists", ubi_num);
864 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
869 ubi->ubi_num = ubi_num;
870 ubi->vid_hdr_offset = vid_hdr_offset;
871 ubi->autoresize_vol_id = -1;
873 mutex_init(&ubi->buf_mutex);
874 mutex_init(&ubi->ckvol_mutex);
875 mutex_init(&ubi->device_mutex);
876 spin_lock_init(&ubi->volumes_lock);
878 ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
885 ubi->peb_buf = vmalloc(ubi->peb_size);
889 err = ubi_debugging_init_dev(ubi);
893 err = ubi_attach(ubi);
895 ubi_err("failed to attach mtd%d, error %d", mtd->index, err);
899 if (ubi->autoresize_vol_id != -1) {
900 err = autoresize(ubi, ubi->autoresize_vol_id);
905 err = uif_init(ubi, &ref);
909 err = ubi_debugfs_init_dev(ubi);
913 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
914 if (IS_ERR(ubi->bgt_thread)) {
915 err = PTR_ERR(ubi->bgt_thread);
916 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
921 ubi_msg("attached mtd%d (name \"%s\", size %llu MiB) to ubi%d",
922 mtd->index, mtd->name, ubi->flash_size >> 20, ubi_num);
923 ubi_msg("PEB size: %d bytes (%d KiB), LEB size: %d bytes",
924 ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
925 ubi_msg("min./max. I/O unit sizes: %d/%d, sub-page size %d",
926 ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
927 ubi_msg("VID header offset: %d (aligned %d), data offset: %d",
928 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
929 ubi_msg("good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
930 ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
931 ubi_msg("user volume: %d, internal volumes: %d, max. volumes count: %d",
932 ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
934 ubi_msg("max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
935 ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
937 ubi_msg("available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
938 ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
941 * The below lock makes sure we do not race with 'ubi_thread()' which
942 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
944 spin_lock(&ubi->wl_lock);
945 ubi->thread_enabled = 1;
946 wake_up_process(ubi->bgt_thread);
947 spin_unlock(&ubi->wl_lock);
949 ubi_devices[ubi_num] = ubi;
950 ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
954 ubi_debugfs_exit_dev(ubi);
956 get_device(&ubi->dev);
961 ubi_free_internal_volumes(ubi);
964 ubi_debugging_exit_dev(ubi);
968 put_device(&ubi->dev);
975 * ubi_detach_mtd_dev - detach an MTD device.
976 * @ubi_num: UBI device number to detach from
977 * @anyway: detach MTD even if device reference count is not zero
979 * This function destroys an UBI device number @ubi_num and detaches the
980 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
981 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
984 * Note, the invocations of this function has to be serialized by the
985 * @ubi_devices_mutex.
987 int ubi_detach_mtd_dev(int ubi_num, int anyway)
989 struct ubi_device *ubi;
991 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
994 ubi = ubi_get_device(ubi_num);
998 spin_lock(&ubi_devices_lock);
999 put_device(&ubi->dev);
1000 ubi->ref_count -= 1;
1001 if (ubi->ref_count) {
1003 spin_unlock(&ubi_devices_lock);
1006 /* This may only happen if there is a bug */
1007 ubi_err("%s reference count %d, destroy anyway",
1008 ubi->ubi_name, ubi->ref_count);
1010 ubi_devices[ubi_num] = NULL;
1011 spin_unlock(&ubi_devices_lock);
1013 ubi_assert(ubi_num == ubi->ubi_num);
1014 ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1015 ubi_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1018 * Before freeing anything, we have to stop the background thread to
1019 * prevent it from doing anything on this device while we are freeing.
1021 if (ubi->bgt_thread)
1022 kthread_stop(ubi->bgt_thread);
1025 * Get a reference to the device in order to prevent 'dev_release()'
1026 * from freeing the @ubi object.
1028 get_device(&ubi->dev);
1030 ubi_debugfs_exit_dev(ubi);
1033 ubi_free_internal_volumes(ubi);
1035 put_mtd_device(ubi->mtd);
1036 ubi_debugging_exit_dev(ubi);
1037 vfree(ubi->peb_buf);
1038 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1039 put_device(&ubi->dev);
1044 * open_mtd_by_chdev - open an MTD device by its character device node path.
1045 * @mtd_dev: MTD character device node path
1047 * This helper function opens an MTD device by its character node device path.
1048 * Returns MTD device description object in case of success and a negative
1049 * error code in case of failure.
1051 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1053 int err, major, minor, mode;
1056 /* Probably this is an MTD character device node path */
1057 err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1059 return ERR_PTR(err);
1061 /* MTD device number is defined by the major / minor numbers */
1062 major = imajor(path.dentry->d_inode);
1063 minor = iminor(path.dentry->d_inode);
1064 mode = path.dentry->d_inode->i_mode;
1066 if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1067 return ERR_PTR(-EINVAL);
1071 * Just do not think the "/dev/mtdrX" devices support is need,
1072 * so do not support them to avoid doing extra work.
1074 return ERR_PTR(-EINVAL);
1076 return get_mtd_device(NULL, minor / 2);
1080 * open_mtd_device - open MTD device by name, character device path, or number.
1081 * @mtd_dev: name, character device node path, or MTD device device number
1083 * This function tries to open and MTD device described by @mtd_dev string,
1084 * which is first treated as ASCII MTD device number, and if it is not true, it
1085 * is treated as MTD device name, and if that is also not true, it is treated
1086 * as MTD character device node path. Returns MTD device description object in
1087 * case of success and a negative error code in case of failure.
1089 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1091 struct mtd_info *mtd;
1095 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1096 if (*endp != '\0' || mtd_dev == endp) {
1098 * This does not look like an ASCII integer, probably this is
1101 mtd = get_mtd_device_nm(mtd_dev);
1102 if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1103 /* Probably this is an MTD character device node path */
1104 mtd = open_mtd_by_chdev(mtd_dev);
1106 mtd = get_mtd_device(NULL, mtd_num);
1111 static int __init ubi_init(void)
1115 /* Ensure that EC and VID headers have correct size */
1116 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1117 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1119 if (mtd_devs > UBI_MAX_DEVICES) {
1120 ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1124 /* Create base sysfs directory and sysfs files */
1125 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1126 if (IS_ERR(ubi_class)) {
1127 err = PTR_ERR(ubi_class);
1128 ubi_err("cannot create UBI class");
1132 err = class_create_file(ubi_class, &ubi_version);
1134 ubi_err("cannot create sysfs file");
1138 err = misc_register(&ubi_ctrl_cdev);
1140 ubi_err("cannot register device");
1144 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1145 sizeof(struct ubi_wl_entry),
1147 if (!ubi_wl_entry_slab)
1150 err = ubi_debugfs_init();
1155 /* Attach MTD devices */
1156 for (i = 0; i < mtd_devs; i++) {
1157 struct mtd_dev_param *p = &mtd_dev_param[i];
1158 struct mtd_info *mtd;
1162 mtd = open_mtd_device(p->name);
1168 mutex_lock(&ubi_devices_mutex);
1169 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
1171 mutex_unlock(&ubi_devices_mutex);
1173 ubi_err("cannot attach mtd%d", mtd->index);
1174 put_mtd_device(mtd);
1177 * Originally UBI stopped initializing on any error.
1178 * However, later on it was found out that this
1179 * behavior is not very good when UBI is compiled into
1180 * the kernel and the MTD devices to attach are passed
1181 * through the command line. Indeed, UBI failure
1182 * stopped whole boot sequence.
1184 * To fix this, we changed the behavior for the
1185 * non-module case, but preserved the old behavior for
1186 * the module case, just for compatibility. This is a
1187 * little inconsistent, though.
1189 if (ubi_is_module())
1197 for (k = 0; k < i; k++)
1198 if (ubi_devices[k]) {
1199 mutex_lock(&ubi_devices_mutex);
1200 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1201 mutex_unlock(&ubi_devices_mutex);
1205 kmem_cache_destroy(ubi_wl_entry_slab);
1207 misc_deregister(&ubi_ctrl_cdev);
1209 class_remove_file(ubi_class, &ubi_version);
1211 class_destroy(ubi_class);
1213 ubi_err("UBI error: cannot initialize UBI, error %d", err);
1216 module_init(ubi_init);
1218 static void __exit ubi_exit(void)
1222 for (i = 0; i < UBI_MAX_DEVICES; i++)
1223 if (ubi_devices[i]) {
1224 mutex_lock(&ubi_devices_mutex);
1225 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1226 mutex_unlock(&ubi_devices_mutex);
1229 kmem_cache_destroy(ubi_wl_entry_slab);
1230 misc_deregister(&ubi_ctrl_cdev);
1231 class_remove_file(ubi_class, &ubi_version);
1232 class_destroy(ubi_class);
1234 module_exit(ubi_exit);
1237 * bytes_str_to_int - convert a number of bytes string into an integer.
1238 * @str: the string to convert
1240 * This function returns positive resulting integer in case of success and a
1241 * negative error code in case of failure.
1243 static int __init bytes_str_to_int(const char *str)
1246 unsigned long result;
1248 result = simple_strtoul(str, &endp, 0);
1249 if (str == endp || result >= INT_MAX) {
1250 ubi_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1261 if (endp[1] == 'i' && endp[2] == 'B')
1266 ubi_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1274 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1275 * @val: the parameter value to parse
1278 * This function returns zero in case of success and a negative error code in
1281 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1284 struct mtd_dev_param *p;
1285 char buf[MTD_PARAM_LEN_MAX];
1286 char *pbuf = &buf[0];
1287 char *tokens[2] = {NULL, NULL};
1292 if (mtd_devs == UBI_MAX_DEVICES) {
1293 ubi_err("UBI error: too many parameters, max. is %d\n",
1298 len = strnlen(val, MTD_PARAM_LEN_MAX);
1299 if (len == MTD_PARAM_LEN_MAX) {
1300 ubi_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1301 val, MTD_PARAM_LEN_MAX);
1306 pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1312 /* Get rid of the final newline */
1313 if (buf[len - 1] == '\n')
1314 buf[len - 1] = '\0';
1316 for (i = 0; i < 2; i++)
1317 tokens[i] = strsep(&pbuf, ",");
1320 ubi_err("UBI error: too many arguments at \"%s\"\n", val);
1324 p = &mtd_dev_param[mtd_devs];
1325 strcpy(&p->name[0], tokens[0]);
1328 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1330 if (p->vid_hdr_offs < 0)
1331 return p->vid_hdr_offs;
1337 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1338 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1339 "mtd=<name|num|path>[,<vid_hdr_offs>].\n"
1340 "Multiple \"mtd\" parameters may be specified.\n"
1341 "MTD devices may be specified by their number, name, or "
1342 "path to the MTD character device node.\n"
1343 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1344 "header position to be used by UBI.\n"
1345 "Example 1: mtd=/dev/mtd0 - attach MTD device "
1347 "Example 2: mtd=content,1984 mtd=4 - attach MTD device "
1348 "with name \"content\" using VID header offset 1984, and "
1349 "MTD device number 4 with default VID header offset.");
1351 MODULE_VERSION(__stringify(UBI_VERSION));
1352 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1353 MODULE_AUTHOR("Artem Bityutskiy");
1354 MODULE_LICENSE("GPL");