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
56 char name[MTD_PARAM_LEN_MAX];
60 /* Numbers of elements set in the @mtd_dev_param array */
61 static int mtd_devs = 0;
63 /* MTD devices specification parameters */
64 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
66 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
67 struct class *ubi_class;
69 /* Slab cache for lock-tree entries */
70 struct kmem_cache *ubi_ltree_slab;
72 /* Slab cache for wear-leveling entries */
73 struct kmem_cache *ubi_wl_entry_slab;
75 /* UBI control character device */
76 static struct miscdevice ubi_ctrl_cdev = {
77 .minor = MISC_DYNAMIC_MINOR,
79 .fops = &ubi_ctrl_cdev_operations,
82 /* All UBI devices in system */
83 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
85 /* Serializes UBI devices creations and removals */
86 DEFINE_MUTEX(ubi_devices_mutex);
88 /* Protects @ubi_devices and @ubi->ref_count */
89 static DEFINE_SPINLOCK(ubi_devices_lock);
91 /* "Show" method for files in '/<sysfs>/class/ubi/' */
92 static ssize_t ubi_version_show(struct class *class, char *buf)
94 return sprintf(buf, "%d\n", UBI_VERSION);
97 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
98 static struct class_attribute ubi_version =
99 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
101 static ssize_t dev_attribute_show(struct device *dev,
102 struct device_attribute *attr, char *buf);
104 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
105 static struct device_attribute dev_eraseblock_size =
106 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
107 static struct device_attribute dev_avail_eraseblocks =
108 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
109 static struct device_attribute dev_total_eraseblocks =
110 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
111 static struct device_attribute dev_volumes_count =
112 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
113 static struct device_attribute dev_max_ec =
114 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
115 static struct device_attribute dev_reserved_for_bad =
116 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
117 static struct device_attribute dev_bad_peb_count =
118 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
119 static struct device_attribute dev_max_vol_count =
120 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
121 static struct device_attribute dev_min_io_size =
122 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
123 static struct device_attribute dev_bgt_enabled =
124 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
127 * ubi_get_device - get UBI device.
128 * @ubi_num: UBI device number
130 * This function returns UBI device description object for UBI device number
131 * @ubi_num, or %NULL if the device does not exist. This function increases the
132 * device reference count to prevent removal of the device. In other words, the
133 * device cannot be removed if its reference count is not zero.
135 struct ubi_device *ubi_get_device(int ubi_num)
137 struct ubi_device *ubi;
139 spin_lock(&ubi_devices_lock);
140 ubi = ubi_devices[ubi_num];
142 ubi_assert(ubi->ref_count >= 0);
144 get_device(&ubi->dev);
146 spin_unlock(&ubi_devices_lock);
152 * ubi_put_device - drop an UBI device reference.
153 * @ubi: UBI device description object
155 void ubi_put_device(struct ubi_device *ubi)
157 spin_lock(&ubi_devices_lock);
159 put_device(&ubi->dev);
160 spin_unlock(&ubi_devices_lock);
164 * ubi_get_by_major - get UBI device description object by character device
166 * @major: major number
168 * This function is similar to 'ubi_get_device()', but it searches the device
169 * by its major number.
171 struct ubi_device *ubi_get_by_major(int major)
174 struct ubi_device *ubi;
176 spin_lock(&ubi_devices_lock);
177 for (i = 0; i < UBI_MAX_DEVICES; i++) {
178 ubi = ubi_devices[i];
179 if (ubi && MAJOR(ubi->cdev.dev) == major) {
180 ubi_assert(ubi->ref_count >= 0);
182 get_device(&ubi->dev);
183 spin_unlock(&ubi_devices_lock);
187 spin_unlock(&ubi_devices_lock);
193 * ubi_major2num - get UBI device number by character device major number.
194 * @major: major number
196 * This function searches UBI device number object by its major number. If UBI
197 * device was not found, this function returns -ENODEV, otherwise the UBI device
198 * number is returned.
200 int ubi_major2num(int major)
202 int i, ubi_num = -ENODEV;
204 spin_lock(&ubi_devices_lock);
205 for (i = 0; i < UBI_MAX_DEVICES; i++) {
206 struct ubi_device *ubi = ubi_devices[i];
208 if (ubi && MAJOR(ubi->cdev.dev) == major) {
209 ubi_num = ubi->ubi_num;
213 spin_unlock(&ubi_devices_lock);
218 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
219 static ssize_t dev_attribute_show(struct device *dev,
220 struct device_attribute *attr, char *buf)
223 struct ubi_device *ubi;
226 * The below code looks weird, but it actually makes sense. We get the
227 * UBI device reference from the contained 'struct ubi_device'. But it
228 * is unclear if the device was removed or not yet. Indeed, if the
229 * device was removed before we increased its reference count,
230 * 'ubi_get_device()' will return -ENODEV and we fail.
232 * Remember, 'struct ubi_device' is freed in the release function, so
233 * we still can use 'ubi->ubi_num'.
235 ubi = container_of(dev, struct ubi_device, dev);
236 ubi = ubi_get_device(ubi->ubi_num);
240 if (attr == &dev_eraseblock_size)
241 ret = sprintf(buf, "%d\n", ubi->leb_size);
242 else if (attr == &dev_avail_eraseblocks)
243 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
244 else if (attr == &dev_total_eraseblocks)
245 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
246 else if (attr == &dev_volumes_count)
247 ret = sprintf(buf, "%d\n", ubi->vol_count);
248 else if (attr == &dev_max_ec)
249 ret = sprintf(buf, "%d\n", ubi->max_ec);
250 else if (attr == &dev_reserved_for_bad)
251 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
252 else if (attr == &dev_bad_peb_count)
253 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
254 else if (attr == &dev_max_vol_count)
255 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
256 else if (attr == &dev_min_io_size)
257 ret = sprintf(buf, "%d\n", ubi->min_io_size);
258 else if (attr == &dev_bgt_enabled)
259 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
267 /* Fake "release" method for UBI devices */
268 static void dev_release(struct device *dev) { }
271 * ubi_sysfs_init - initialize sysfs for an UBI device.
272 * @ubi: UBI device description object
274 * This function returns zero in case of success and a negative error code in
277 static int ubi_sysfs_init(struct ubi_device *ubi)
281 ubi->dev.release = dev_release;
282 ubi->dev.devt = ubi->cdev.dev;
283 ubi->dev.class = ubi_class;
284 sprintf(&ubi->dev.bus_id[0], UBI_NAME_STR"%d", ubi->ubi_num);
285 err = device_register(&ubi->dev);
289 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
292 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
295 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
298 err = device_create_file(&ubi->dev, &dev_volumes_count);
301 err = device_create_file(&ubi->dev, &dev_max_ec);
304 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
307 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
310 err = device_create_file(&ubi->dev, &dev_max_vol_count);
313 err = device_create_file(&ubi->dev, &dev_min_io_size);
316 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
321 * ubi_sysfs_close - close sysfs for an UBI device.
322 * @ubi: UBI device description object
324 static void ubi_sysfs_close(struct ubi_device *ubi)
326 device_remove_file(&ubi->dev, &dev_bgt_enabled);
327 device_remove_file(&ubi->dev, &dev_min_io_size);
328 device_remove_file(&ubi->dev, &dev_max_vol_count);
329 device_remove_file(&ubi->dev, &dev_bad_peb_count);
330 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
331 device_remove_file(&ubi->dev, &dev_max_ec);
332 device_remove_file(&ubi->dev, &dev_volumes_count);
333 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
334 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
335 device_remove_file(&ubi->dev, &dev_eraseblock_size);
336 device_unregister(&ubi->dev);
340 * kill_volumes - destroy all volumes.
341 * @ubi: UBI device description object
343 static void kill_volumes(struct ubi_device *ubi)
347 for (i = 0; i < ubi->vtbl_slots; i++)
349 ubi_free_volume(ubi, ubi->volumes[i]);
353 * uif_init - initialize user interfaces for an UBI device.
354 * @ubi: UBI device description object
356 * This function returns zero in case of success and a negative error code in
359 static int uif_init(struct ubi_device *ubi)
364 mutex_init(&ubi->volumes_mutex);
365 spin_lock_init(&ubi->volumes_lock);
367 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
370 * Major numbers for the UBI character devices are allocated
371 * dynamically. Major numbers of volume character devices are
372 * equivalent to ones of the corresponding UBI character device. Minor
373 * numbers of UBI character devices are 0, while minor numbers of
374 * volume character devices start from 1. Thus, we allocate one major
375 * number and ubi->vtbl_slots + 1 minor numbers.
377 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
379 ubi_err("cannot register UBI character devices");
383 ubi_assert(MINOR(dev) == 0);
384 cdev_init(&ubi->cdev, &ubi_cdev_operations);
385 dbg_msg("%s major is %u", ubi->ubi_name, MAJOR(dev));
386 ubi->cdev.owner = THIS_MODULE;
388 err = cdev_add(&ubi->cdev, dev, 1);
390 ubi_err("cannot add character device");
394 err = ubi_sysfs_init(ubi);
398 for (i = 0; i < ubi->vtbl_slots; i++)
399 if (ubi->volumes[i]) {
400 err = ubi_add_volume(ubi, ubi->volumes[i]);
402 ubi_err("cannot add volume %d", i);
412 ubi_sysfs_close(ubi);
413 cdev_del(&ubi->cdev);
415 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
416 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
421 * uif_close - close user interfaces for an UBI device.
422 * @ubi: UBI device description object
424 static void uif_close(struct ubi_device *ubi)
427 ubi_sysfs_close(ubi);
428 cdev_del(&ubi->cdev);
429 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
433 * attach_by_scanning - attach an MTD device using scanning method.
434 * @ubi: UBI device descriptor
436 * This function returns zero in case of success and a negative error code in
439 * Note, currently this is the only method to attach UBI devices. Hopefully in
440 * the future we'll have more scalable attaching methods and avoid full media
441 * scanning. But even in this case scanning will be needed as a fall-back
442 * attaching method if there are some on-flash table corruptions.
444 static int attach_by_scanning(struct ubi_device *ubi)
447 struct ubi_scan_info *si;
453 ubi->bad_peb_count = si->bad_peb_count;
454 ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
455 ubi->max_ec = si->max_ec;
456 ubi->mean_ec = si->mean_ec;
458 err = ubi_read_volume_table(ubi, si);
462 err = ubi_wl_init_scan(ubi, si);
466 err = ubi_eba_init_scan(ubi, si);
470 ubi_scan_destroy_si(si);
478 ubi_scan_destroy_si(si);
483 * io_init - initialize I/O unit for a given UBI device.
484 * @ubi: UBI device description object
486 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
488 * o EC header is always at offset zero - this cannot be changed;
489 * o VID header starts just after the EC header at the closest address
490 * aligned to @io->hdrs_min_io_size;
491 * o data starts just after the VID header at the closest address aligned to
494 * This function returns zero in case of success and a negative error code in
497 static int io_init(struct ubi_device *ubi)
499 if (ubi->mtd->numeraseregions != 0) {
501 * Some flashes have several erase regions. Different regions
502 * may have different eraseblock size and other
503 * characteristics. It looks like mostly multi-region flashes
504 * have one "main" region and one or more small regions to
505 * store boot loader code or boot parameters or whatever. I
506 * guess we should just pick the largest region. But this is
509 ubi_err("multiple regions, not implemented");
513 if (ubi->vid_hdr_offset < 0)
517 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
518 * physical eraseblocks maximum.
521 ubi->peb_size = ubi->mtd->erasesize;
522 ubi->peb_count = ubi->mtd->size / ubi->mtd->erasesize;
523 ubi->flash_size = ubi->mtd->size;
525 if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
526 ubi->bad_allowed = 1;
528 ubi->min_io_size = ubi->mtd->writesize;
529 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
531 /* Make sure minimal I/O unit is power of 2 */
532 if (!is_power_of_2(ubi->min_io_size)) {
533 ubi_err("min. I/O unit (%d) is not power of 2",
538 ubi_assert(ubi->hdrs_min_io_size > 0);
539 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
540 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
542 /* Calculate default aligned sizes of EC and VID headers */
543 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
544 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
546 dbg_msg("min_io_size %d", ubi->min_io_size);
547 dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
548 dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
549 dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
551 if (ubi->vid_hdr_offset == 0)
553 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
556 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
557 ~(ubi->hdrs_min_io_size - 1);
558 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
559 ubi->vid_hdr_aloffset;
562 /* Similar for the data offset */
563 ubi->leb_start = ubi->vid_hdr_offset + ubi->vid_hdr_alsize;
564 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
566 dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
567 dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
568 dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
569 dbg_msg("leb_start %d", ubi->leb_start);
571 /* The shift must be aligned to 32-bit boundary */
572 if (ubi->vid_hdr_shift % 4) {
573 ubi_err("unaligned VID header shift %d",
579 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
580 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
581 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
582 ubi->leb_start % ubi->min_io_size) {
583 ubi_err("bad VID header (%d) or data offsets (%d)",
584 ubi->vid_hdr_offset, ubi->leb_start);
589 * It may happen that EC and VID headers are situated in one minimal
590 * I/O unit. In this case we can only accept this UBI image in
593 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
594 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
595 "switch to read-only mode");
599 ubi->leb_size = ubi->peb_size - ubi->leb_start;
601 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
602 ubi_msg("MTD device %d is write-protected, attach in "
603 "read-only mode", ubi->mtd->index);
607 dbg_msg("leb_size %d", ubi->leb_size);
608 dbg_msg("ro_mode %d", ubi->ro_mode);
611 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
612 * unfortunately, MTD does not provide this information. We should loop
613 * over all physical eraseblocks and invoke mtd->block_is_bad() for
614 * each physical eraseblock. So, we skip ubi->bad_peb_count
615 * uninitialized and initialize it after scanning.
622 * ubi_attach_mtd_dev - attach an MTD device.
623 * @mtd_dev: MTD device description object
624 * @ubi_num: number to assign to the new UBI device
625 * @vid_hdr_offset: VID header offset
627 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
628 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
629 * which case this function finds a vacant device nubert and assings it
630 * automatically. Returns the new UBI device number in case of success and a
631 * negative error code in case of failure.
633 * Note, the invocations of this function has to be serialized by the
634 * @ubi_devices_mutex.
636 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
638 struct ubi_device *ubi;
642 * Check if we already have the same MTD device attached.
644 * Note, this function assumes that UBI devices creations and deletions
645 * are serialized, so it does not take the &ubi_devices_lock.
647 for (i = 0; i < UBI_MAX_DEVICES; i++) {
648 ubi = ubi_devices[i];
649 if (ubi && mtd->index == ubi->mtd->index) {
650 dbg_err("mtd%d is already attached to ubi%d",
657 * Make sure this MTD device is not emulated on top of an UBI volume
658 * already. Well, generally this recursion works fine, but there are
659 * different problems like the UBI module takes a reference to itself
660 * by attaching (and thus, opening) the emulated MTD device. This
661 * results in inability to unload the module. And in general it makes
662 * no sense to attach emulated MTD devices, so we prohibit this.
664 if (mtd->type == MTD_UBIVOLUME) {
665 ubi_err("refuse attaching mtd%d - it is already emulated on "
666 "top of UBI", mtd->index);
670 if (ubi_num == UBI_DEV_NUM_AUTO) {
671 /* Search for an empty slot in the @ubi_devices array */
672 for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
673 if (!ubi_devices[ubi_num])
675 if (ubi_num == UBI_MAX_DEVICES) {
676 dbg_err("only %d UBI devices may be created", UBI_MAX_DEVICES);
680 if (ubi_num >= UBI_MAX_DEVICES)
683 /* Make sure ubi_num is not busy */
684 if (ubi_devices[ubi_num]) {
685 dbg_err("ubi%d already exists", ubi_num);
690 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
695 ubi->ubi_num = ubi_num;
696 ubi->vid_hdr_offset = vid_hdr_offset;
698 dbg_msg("attaching mtd%d to ubi%d: VID header offset %d",
699 mtd->index, ubi_num, vid_hdr_offset);
705 mutex_init(&ubi->buf_mutex);
706 mutex_init(&ubi->ckvol_mutex);
707 ubi->peb_buf1 = vmalloc(ubi->peb_size);
711 ubi->peb_buf2 = vmalloc(ubi->peb_size);
715 #ifdef CONFIG_MTD_UBI_DEBUG
716 mutex_init(&ubi->dbg_buf_mutex);
717 ubi->dbg_peb_buf = vmalloc(ubi->peb_size);
718 if (!ubi->dbg_peb_buf)
722 err = attach_by_scanning(ubi);
724 dbg_err("failed to attach by scanning, error %d", err);
732 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
733 if (IS_ERR(ubi->bgt_thread)) {
734 err = PTR_ERR(ubi->bgt_thread);
735 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
740 ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num);
741 ubi_msg("MTD device name: \"%s\"", mtd->name);
742 ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
743 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
744 ubi->peb_size, ubi->peb_size >> 10);
745 ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
746 ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
747 ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
748 ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
749 ubi_msg("VID header offset: %d (aligned %d)",
750 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
751 ubi_msg("data offset: %d", ubi->leb_start);
752 ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
753 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
754 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
755 ubi_msg("number of user volumes: %d",
756 ubi->vol_count - UBI_INT_VOL_COUNT);
757 ubi_msg("available PEBs: %d", ubi->avail_pebs);
758 ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
759 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
761 ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
763 /* Enable the background thread */
764 if (!DBG_DISABLE_BGT) {
765 ubi->thread_enabled = 1;
766 wake_up_process(ubi->bgt_thread);
769 ubi_devices[ubi_num] = ubi;
779 vfree(ubi->peb_buf1);
780 vfree(ubi->peb_buf2);
781 #ifdef CONFIG_MTD_UBI_DEBUG
782 vfree(ubi->dbg_peb_buf);
789 * ubi_detach_mtd_dev - detach an MTD device.
790 * @ubi_num: UBI device number to detach from
791 * @anyway: detach MTD even if device reference count is not zero
793 * This function destroys an UBI device number @ubi_num and detaches the
794 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
795 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
798 * Note, the invocations of this function has to be serialized by the
799 * @ubi_devices_mutex.
801 int ubi_detach_mtd_dev(int ubi_num, int anyway)
803 struct ubi_device *ubi;
805 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
808 spin_lock(&ubi_devices_lock);
809 ubi = ubi_devices[ubi_num];
811 spin_unlock(&ubi_devices_lock);
815 if (ubi->ref_count) {
817 spin_unlock(&ubi_devices_lock);
820 /* This may only happen if there is a bug */
821 ubi_err("%s reference count %d, destroy anyway",
822 ubi->ubi_name, ubi->ref_count);
824 ubi_devices[ubi_num] = NULL;
825 spin_unlock(&ubi_devices_lock);
827 ubi_assert(ubi_num == ubi->ubi_num);
828 dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
831 * Before freeing anything, we have to stop the background thread to
832 * prevent it from doing anything on this device while we are freeing.
835 kthread_stop(ubi->bgt_thread);
841 put_mtd_device(ubi->mtd);
842 vfree(ubi->peb_buf1);
843 vfree(ubi->peb_buf2);
844 #ifdef CONFIG_MTD_UBI_DEBUG
845 vfree(ubi->dbg_peb_buf);
847 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
853 * ltree_entry_ctor - lock tree entries slab cache constructor.
854 * @obj: the lock-tree entry to construct
855 * @cache: the lock tree entry slab cache
856 * @flags: constructor flags
858 static void ltree_entry_ctor(struct kmem_cache *cache, void *obj)
860 struct ubi_ltree_entry *le = obj;
863 init_rwsem(&le->mutex);
867 * find_mtd_device - open an MTD device by its name or number.
868 * @mtd_dev: name or number of the device
870 * This function tries to open and MTD device with name @mtd_dev, and if it
871 * fails, then it tries to interpret the @mtd_dev string as an ASCII-coded
872 * integer and open an MTD device with this number. Returns MTD device
873 * description object in case of success and a negative error code in case of
876 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
878 struct mtd_info *mtd;
880 mtd = get_mtd_device_nm(mtd_dev);
885 if (PTR_ERR(mtd) != -ENODEV)
889 * Probably this is not MTD device name but MTD device number -
892 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
893 if (*endp != '\0' || mtd_dev == endp) {
894 ubi_err("incorrect MTD device: \"%s\"", mtd_dev);
895 return ERR_PTR(-ENODEV);
898 mtd = get_mtd_device(NULL, mtd_num);
906 static int __init ubi_init(void)
910 /* Ensure that EC and VID headers have correct size */
911 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
912 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
914 if (mtd_devs > UBI_MAX_DEVICES) {
915 printk(KERN_ERR "UBI error: too many MTD devices, "
916 "maximum is %d\n", UBI_MAX_DEVICES);
920 /* Create base sysfs directory and sysfs files */
921 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
922 if (IS_ERR(ubi_class)) {
923 err = PTR_ERR(ubi_class);
924 printk(KERN_ERR "UBI error: cannot create UBI class\n");
928 err = class_create_file(ubi_class, &ubi_version);
930 printk(KERN_ERR "UBI error: cannot create sysfs file\n");
934 err = misc_register(&ubi_ctrl_cdev);
936 printk(KERN_ERR "UBI error: cannot register device\n");
940 ubi_ltree_slab = kmem_cache_create("ubi_ltree_slab",
941 sizeof(struct ubi_ltree_entry), 0,
942 0, <ree_entry_ctor);
946 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
947 sizeof(struct ubi_wl_entry),
949 if (!ubi_wl_entry_slab)
952 /* Attach MTD devices */
953 for (i = 0; i < mtd_devs; i++) {
954 struct mtd_dev_param *p = &mtd_dev_param[i];
955 struct mtd_info *mtd;
959 mtd = open_mtd_device(p->name);
965 mutex_lock(&ubi_devices_mutex);
966 err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO,
968 mutex_unlock(&ubi_devices_mutex);
971 printk(KERN_ERR "UBI error: cannot attach %s\n",
980 for (k = 0; k < i; k++)
981 if (ubi_devices[k]) {
982 mutex_lock(&ubi_devices_mutex);
983 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
984 mutex_unlock(&ubi_devices_mutex);
986 kmem_cache_destroy(ubi_wl_entry_slab);
988 kmem_cache_destroy(ubi_ltree_slab);
990 misc_deregister(&ubi_ctrl_cdev);
992 class_remove_file(ubi_class, &ubi_version);
994 class_destroy(ubi_class);
996 printk(KERN_ERR "UBI error: cannot initialize UBI, error %d\n", err);
999 module_init(ubi_init);
1001 static void __exit ubi_exit(void)
1005 for (i = 0; i < UBI_MAX_DEVICES; i++)
1006 if (ubi_devices[i]) {
1007 mutex_lock(&ubi_devices_mutex);
1008 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1009 mutex_unlock(&ubi_devices_mutex);
1011 kmem_cache_destroy(ubi_wl_entry_slab);
1012 kmem_cache_destroy(ubi_ltree_slab);
1013 misc_deregister(&ubi_ctrl_cdev);
1014 class_remove_file(ubi_class, &ubi_version);
1015 class_destroy(ubi_class);
1017 module_exit(ubi_exit);
1020 * bytes_str_to_int - convert a string representing number of bytes to an
1022 * @str: the string to convert
1024 * This function returns positive resulting integer in case of success and a
1025 * negative error code in case of failure.
1027 static int __init bytes_str_to_int(const char *str)
1030 unsigned long result;
1032 result = simple_strtoul(str, &endp, 0);
1033 if (str == endp || result < 0) {
1034 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1047 if (endp[1] == 'i' && (endp[2] == '\0' ||
1048 endp[2] == 'B' || endp[2] == 'b'))
1053 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1062 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1063 * @val: the parameter value to parse
1066 * This function returns zero in case of success and a negative error code in
1069 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1072 struct mtd_dev_param *p;
1073 char buf[MTD_PARAM_LEN_MAX];
1074 char *pbuf = &buf[0];
1075 char *tokens[3] = {NULL, NULL, NULL};
1080 if (mtd_devs == UBI_MAX_DEVICES) {
1081 printk(KERN_ERR "UBI error: too many parameters, max. is %d\n",
1086 len = strnlen(val, MTD_PARAM_LEN_MAX);
1087 if (len == MTD_PARAM_LEN_MAX) {
1088 printk(KERN_ERR "UBI error: parameter \"%s\" is too long, "
1089 "max. is %d\n", val, MTD_PARAM_LEN_MAX);
1094 printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - "
1101 /* Get rid of the final newline */
1102 if (buf[len - 1] == '\n')
1103 buf[len - 1] = '\0';
1105 for (i = 0; i < 3; i++)
1106 tokens[i] = strsep(&pbuf, ",");
1109 printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n",
1114 p = &mtd_dev_param[mtd_devs];
1115 strcpy(&p->name[0], tokens[0]);
1118 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1120 if (p->vid_hdr_offs < 0)
1121 return p->vid_hdr_offs;
1127 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1128 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1129 "mtd=<name|num>[,<vid_hdr_offs>].\n"
1130 "Multiple \"mtd\" parameters may be specified.\n"
1131 "MTD devices may be specified by their number or name.\n"
1132 "Optional \"vid_hdr_offs\" parameter specifies UBI VID "
1133 "header position and data starting position to be used "
1135 "Example: mtd=content,1984 mtd=4 - attach MTD device"
1136 "with name \"content\" using VID header offset 1984, and "
1137 "MTD device number 4 with default VID header offset.");
1139 MODULE_VERSION(__stringify(UBI_VERSION));
1140 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1141 MODULE_AUTHOR("Artem Bityutskiy");
1142 MODULE_LICENSE("GPL");