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
53 * @data_offs: data offset
57 char name[MTD_PARAM_LEN_MAX];
62 /* Numbers of elements set in the @mtd_dev_param array */
63 static int mtd_devs = 0;
65 /* MTD devices specification parameters */
66 static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
68 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
69 struct class *ubi_class;
71 /* Slab cache for lock-tree entries */
72 struct kmem_cache *ubi_ltree_slab;
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, char *buf)
96 return sprintf(buf, "%d\n", UBI_VERSION);
99 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
100 static struct class_attribute ubi_version =
101 __ATTR(version, S_IRUGO, ubi_version_show, NULL);
103 static ssize_t dev_attribute_show(struct device *dev,
104 struct device_attribute *attr, char *buf);
106 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
107 static struct device_attribute dev_eraseblock_size =
108 __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
109 static struct device_attribute dev_avail_eraseblocks =
110 __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
111 static struct device_attribute dev_total_eraseblocks =
112 __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
113 static struct device_attribute dev_volumes_count =
114 __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
115 static struct device_attribute dev_max_ec =
116 __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
117 static struct device_attribute dev_reserved_for_bad =
118 __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
119 static struct device_attribute dev_bad_peb_count =
120 __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
121 static struct device_attribute dev_max_vol_count =
122 __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
123 static struct device_attribute dev_min_io_size =
124 __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
125 static struct device_attribute dev_bgt_enabled =
126 __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
129 * ubi_get_device - get UBI device.
130 * @ubi_num: UBI device number
132 * This function returns UBI device description object for UBI device number
133 * @ubi_num, or %NULL if the device does not exist. This function increases the
134 * device reference count to prevent removal of the device. In other words, the
135 * device cannot be removed if its reference count is not zero.
137 struct ubi_device *ubi_get_device(int ubi_num)
139 struct ubi_device *ubi;
141 spin_lock(&ubi_devices_lock);
142 ubi = ubi_devices[ubi_num];
144 ubi_assert(ubi->ref_count >= 0);
146 get_device(&ubi->dev);
148 spin_unlock(&ubi_devices_lock);
154 * ubi_put_device - drop an UBI device reference.
155 * @ubi: UBI device description object
157 void ubi_put_device(struct ubi_device *ubi)
159 spin_lock(&ubi_devices_lock);
161 put_device(&ubi->dev);
162 spin_unlock(&ubi_devices_lock);
166 * ubi_get_by_major - get UBI device description object by character device
168 * @major: major number
170 * This function is similar to 'ubi_get_device()', but it searches the device
171 * by its major number.
173 struct ubi_device *ubi_get_by_major(int major)
176 struct ubi_device *ubi;
178 spin_lock(&ubi_devices_lock);
179 for (i = 0; i < UBI_MAX_DEVICES; i++) {
180 ubi = ubi_devices[i];
181 if (ubi && MAJOR(ubi->cdev.dev) == major) {
182 ubi_assert(ubi->ref_count >= 0);
184 get_device(&ubi->dev);
185 spin_unlock(&ubi_devices_lock);
189 spin_unlock(&ubi_devices_lock);
195 * ubi_major2num - get UBI device number by character device major number.
196 * @major: major number
198 * This function searches UBI device number object by its major number. If UBI
199 * device was not found, this function returns -ENODEV, otherwise the UBI device
200 * number is returned.
202 int ubi_major2num(int major)
204 int i, ubi_num = -ENODEV;
206 spin_lock(&ubi_devices_lock);
207 for (i = 0; i < UBI_MAX_DEVICES; i++) {
208 struct ubi_device *ubi = ubi_devices[i];
210 if (ubi && MAJOR(ubi->cdev.dev) == major) {
211 ubi_num = ubi->ubi_num;
215 spin_unlock(&ubi_devices_lock);
220 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
221 static ssize_t dev_attribute_show(struct device *dev,
222 struct device_attribute *attr, char *buf)
225 struct ubi_device *ubi;
228 * The below code looks weird, but it actually makes sense. We get the
229 * UBI device reference from the contained 'struct ubi_device'. But it
230 * is unclear if the device was removed or not yet. Indeed, if the
231 * device was removed before we increased its reference count,
232 * 'ubi_get_device()' will return -ENODEV and we fail.
234 * Remember, 'struct ubi_device' is freed in the release function, so
235 * we still can use 'ubi->ubi_num'.
237 ubi = container_of(dev, struct ubi_device, dev);
238 ubi = ubi_get_device(ubi->ubi_num);
242 if (attr == &dev_eraseblock_size)
243 ret = sprintf(buf, "%d\n", ubi->leb_size);
244 else if (attr == &dev_avail_eraseblocks)
245 ret = sprintf(buf, "%d\n", ubi->avail_pebs);
246 else if (attr == &dev_total_eraseblocks)
247 ret = sprintf(buf, "%d\n", ubi->good_peb_count);
248 else if (attr == &dev_volumes_count)
249 ret = sprintf(buf, "%d\n", ubi->vol_count);
250 else if (attr == &dev_max_ec)
251 ret = sprintf(buf, "%d\n", ubi->max_ec);
252 else if (attr == &dev_reserved_for_bad)
253 ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
254 else if (attr == &dev_bad_peb_count)
255 ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
256 else if (attr == &dev_max_vol_count)
257 ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
258 else if (attr == &dev_min_io_size)
259 ret = sprintf(buf, "%d\n", ubi->min_io_size);
260 else if (attr == &dev_bgt_enabled)
261 ret = sprintf(buf, "%d\n", ubi->thread_enabled);
269 /* Fake "release" method for UBI devices */
270 static void dev_release(struct device *dev) { }
273 * ubi_sysfs_init - initialize sysfs for an UBI device.
274 * @ubi: UBI device description object
276 * This function returns zero in case of success and a negative error code in
279 static int ubi_sysfs_init(struct ubi_device *ubi)
283 ubi->dev.release = dev_release;
284 ubi->dev.devt = ubi->cdev.dev;
285 ubi->dev.class = ubi_class;
286 sprintf(&ubi->dev.bus_id[0], UBI_NAME_STR"%d", ubi->ubi_num);
287 err = device_register(&ubi->dev);
291 err = device_create_file(&ubi->dev, &dev_eraseblock_size);
294 err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
297 err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
300 err = device_create_file(&ubi->dev, &dev_volumes_count);
303 err = device_create_file(&ubi->dev, &dev_max_ec);
306 err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
309 err = device_create_file(&ubi->dev, &dev_bad_peb_count);
312 err = device_create_file(&ubi->dev, &dev_max_vol_count);
315 err = device_create_file(&ubi->dev, &dev_min_io_size);
318 err = device_create_file(&ubi->dev, &dev_bgt_enabled);
323 * ubi_sysfs_close - close sysfs for an UBI device.
324 * @ubi: UBI device description object
326 static void ubi_sysfs_close(struct ubi_device *ubi)
328 device_remove_file(&ubi->dev, &dev_bgt_enabled);
329 device_remove_file(&ubi->dev, &dev_min_io_size);
330 device_remove_file(&ubi->dev, &dev_max_vol_count);
331 device_remove_file(&ubi->dev, &dev_bad_peb_count);
332 device_remove_file(&ubi->dev, &dev_reserved_for_bad);
333 device_remove_file(&ubi->dev, &dev_max_ec);
334 device_remove_file(&ubi->dev, &dev_volumes_count);
335 device_remove_file(&ubi->dev, &dev_total_eraseblocks);
336 device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
337 device_remove_file(&ubi->dev, &dev_eraseblock_size);
338 device_unregister(&ubi->dev);
342 * kill_volumes - destroy all volumes.
343 * @ubi: UBI device description object
345 static void kill_volumes(struct ubi_device *ubi)
349 for (i = 0; i < ubi->vtbl_slots; i++)
351 ubi_free_volume(ubi, ubi->volumes[i]);
355 * uif_init - initialize user interfaces for an UBI device.
356 * @ubi: UBI device description object
358 * This function returns zero in case of success and a negative error code in
361 static int uif_init(struct ubi_device *ubi)
366 mutex_init(&ubi->volumes_mutex);
367 spin_lock_init(&ubi->volumes_lock);
369 sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
372 * Major numbers for the UBI character devices are allocated
373 * dynamically. Major numbers of volume character devices are
374 * equivalent to ones of the corresponding UBI character device. Minor
375 * numbers of UBI character devices are 0, while minor numbers of
376 * volume character devices start from 1. Thus, we allocate one major
377 * number and ubi->vtbl_slots + 1 minor numbers.
379 err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
381 ubi_err("cannot register UBI character devices");
385 ubi_assert(MINOR(dev) == 0);
386 cdev_init(&ubi->cdev, &ubi_cdev_operations);
387 dbg_msg("%s major is %u", ubi->ubi_name, MAJOR(dev));
388 ubi->cdev.owner = THIS_MODULE;
390 err = cdev_add(&ubi->cdev, dev, 1);
392 ubi_err("cannot add character device");
396 err = ubi_sysfs_init(ubi);
400 for (i = 0; i < ubi->vtbl_slots; i++)
401 if (ubi->volumes[i]) {
402 err = ubi_add_volume(ubi, ubi->volumes[i]);
404 ubi_err("cannot add volume %d", i);
414 ubi_sysfs_close(ubi);
415 cdev_del(&ubi->cdev);
417 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
418 ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
423 * uif_close - close user interfaces for an UBI device.
424 * @ubi: UBI device description object
426 static void uif_close(struct ubi_device *ubi)
429 ubi_sysfs_close(ubi);
430 cdev_del(&ubi->cdev);
431 unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
435 * attach_by_scanning - attach an MTD device using scanning method.
436 * @ubi: UBI device descriptor
438 * This function returns zero in case of success and a negative error code in
441 * Note, currently this is the only method to attach UBI devices. Hopefully in
442 * the future we'll have more scalable attaching methods and avoid full media
443 * scanning. But even in this case scanning will be needed as a fall-back
444 * attaching method if there are some on-flash table corruptions.
446 static int attach_by_scanning(struct ubi_device *ubi)
449 struct ubi_scan_info *si;
455 ubi->bad_peb_count = si->bad_peb_count;
456 ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
457 ubi->max_ec = si->max_ec;
458 ubi->mean_ec = si->mean_ec;
460 err = ubi_read_volume_table(ubi, si);
464 err = ubi_wl_init_scan(ubi, si);
468 err = ubi_eba_init_scan(ubi, si);
472 ubi_scan_destroy_si(si);
480 ubi_scan_destroy_si(si);
485 * io_init - initialize I/O unit for a given UBI device.
486 * @ubi: UBI device description object
488 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
490 * o EC header is always at offset zero - this cannot be changed;
491 * o VID header starts just after the EC header at the closest address
492 * aligned to @io->hdrs_min_io_size;
493 * o data starts just after the VID header at the closest address aligned to
496 * This function returns zero in case of success and a negative error code in
499 static int io_init(struct ubi_device *ubi)
501 if (ubi->mtd->numeraseregions != 0) {
503 * Some flashes have several erase regions. Different regions
504 * may have different eraseblock size and other
505 * characteristics. It looks like mostly multi-region flashes
506 * have one "main" region and one or more small regions to
507 * store boot loader code or boot parameters or whatever. I
508 * guess we should just pick the largest region. But this is
511 ubi_err("multiple regions, not implemented");
515 if (ubi->vid_hdr_offset < 0 || ubi->leb_start < ubi->vid_hdr_offset)
519 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
520 * physical eraseblocks maximum.
523 ubi->peb_size = ubi->mtd->erasesize;
524 ubi->peb_count = ubi->mtd->size / ubi->mtd->erasesize;
525 ubi->flash_size = ubi->mtd->size;
527 if (ubi->mtd->block_isbad && ubi->mtd->block_markbad)
528 ubi->bad_allowed = 1;
530 ubi->min_io_size = ubi->mtd->writesize;
531 ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
533 /* Make sure minimal I/O unit is power of 2 */
534 if (!is_power_of_2(ubi->min_io_size)) {
535 ubi_err("min. I/O unit (%d) is not power of 2",
540 ubi_assert(ubi->hdrs_min_io_size > 0);
541 ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
542 ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
544 /* Calculate default aligned sizes of EC and VID headers */
545 ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
546 ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
548 dbg_msg("min_io_size %d", ubi->min_io_size);
549 dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
550 dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
551 dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
553 if (ubi->vid_hdr_offset == 0)
555 ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
558 ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
559 ~(ubi->hdrs_min_io_size - 1);
560 ubi->vid_hdr_shift = ubi->vid_hdr_offset -
561 ubi->vid_hdr_aloffset;
564 /* Similar for the data offset */
565 if (ubi->leb_start == 0) {
566 ubi->leb_start = ubi->vid_hdr_offset + ubi->vid_hdr_alsize;
567 ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
570 dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset);
571 dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
572 dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift);
573 dbg_msg("leb_start %d", ubi->leb_start);
575 /* The shift must be aligned to 32-bit boundary */
576 if (ubi->vid_hdr_shift % 4) {
577 ubi_err("unaligned VID header shift %d",
583 if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
584 ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
585 ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
586 ubi->leb_start % ubi->min_io_size) {
587 ubi_err("bad VID header (%d) or data offsets (%d)",
588 ubi->vid_hdr_offset, ubi->leb_start);
593 * It may happen that EC and VID headers are situated in one minimal
594 * I/O unit. In this case we can only accept this UBI image in
597 if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
598 ubi_warn("EC and VID headers are in the same minimal I/O unit, "
599 "switch to read-only mode");
603 ubi->leb_size = ubi->peb_size - ubi->leb_start;
605 if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
606 ubi_msg("MTD device %d is write-protected, attach in "
607 "read-only mode", ubi->mtd->index);
611 dbg_msg("leb_size %d", ubi->leb_size);
612 dbg_msg("ro_mode %d", ubi->ro_mode);
615 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
616 * unfortunately, MTD does not provide this information. We should loop
617 * over all physical eraseblocks and invoke mtd->block_is_bad() for
618 * each physical eraseblock. So, we skip ubi->bad_peb_count
619 * uninitialized and initialize it after scanning.
626 * ubi_attach_mtd_dev - attach an MTD device.
627 * @mtd_dev: MTD device description object
628 * @vid_hdr_offset: VID header offset
629 * @data_offset: data offset
631 * This function attaches an MTD device to UBI. It first treats @mtd_dev as the
632 * MTD device name, and tries to open it by this name. If it is unable to open,
633 * it tries to convert @mtd_dev to an integer and open the MTD device by its
634 * number. Returns new UBI device's number in case of success and a negative
635 * error code in case of failure.
637 * Note, the invocations of this function has to be serialized by the
638 * @ubi_devices_mutex.
640 int ubi_attach_mtd_dev(struct mtd_info *mtd, int vid_hdr_offset,
643 struct ubi_device *ubi;
647 * Check if we already have the same MTD device attached.
649 * Note, this function assumes that UBI devices creations and deletions
650 * are serialized, so it does not take the &ubi_devices_lock.
652 for (i = 0; i < UBI_MAX_DEVICES; i++)
653 ubi = ubi_devices[i];
654 if (ubi && mtd->index == ubi->mtd->index) {
655 ubi_err("mtd%d is already attached to ubi%d",
660 /* Search for an empty slot in the @ubi_devices array */
661 for (i = 0; i < UBI_MAX_DEVICES; i++)
665 if (i == UBI_MAX_DEVICES) {
666 ubi_err("only %d UBI devices may be created", UBI_MAX_DEVICES);
670 ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
676 ubi->vid_hdr_offset = vid_hdr_offset;
677 ubi->leb_start = data_offset;
679 dbg_msg("attaching mtd%d to ubi%d: VID header offset %d data offset %d",
680 mtd->index, ubi->ubi_num, vid_hdr_offset, data_offset);
686 mutex_init(&ubi->buf_mutex);
687 ubi->peb_buf1 = vmalloc(ubi->peb_size);
691 ubi->peb_buf2 = vmalloc(ubi->peb_size);
695 #ifdef CONFIG_MTD_UBI_DEBUG
696 mutex_init(&ubi->dbg_buf_mutex);
697 ubi->dbg_peb_buf = vmalloc(ubi->peb_size);
698 if (!ubi->dbg_peb_buf)
702 err = attach_by_scanning(ubi);
704 dbg_err("failed to attach by scanning, error %d", err);
712 ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
713 if (IS_ERR(ubi->bgt_thread)) {
714 err = PTR_ERR(ubi->bgt_thread);
715 ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
720 ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi->ubi_num);
721 ubi_msg("MTD device name: \"%s\"", mtd->name);
722 ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20);
723 ubi_msg("physical eraseblock size: %d bytes (%d KiB)",
724 ubi->peb_size, ubi->peb_size >> 10);
725 ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size);
726 ubi_msg("number of good PEBs: %d", ubi->good_peb_count);
727 ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count);
728 ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size);
729 ubi_msg("VID header offset: %d (aligned %d)",
730 ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
731 ubi_msg("data offset: %d", ubi->leb_start);
732 ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots);
733 ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD);
734 ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
735 ubi_msg("number of user volumes: %d",
736 ubi->vol_count - UBI_INT_VOL_COUNT);
737 ubi_msg("available PEBs: %d", ubi->avail_pebs);
738 ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs);
739 ubi_msg("number of PEBs reserved for bad PEB handling: %d",
741 ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec);
743 /* Enable the background thread */
744 if (!DBG_DISABLE_BGT) {
745 ubi->thread_enabled = 1;
746 wake_up_process(ubi->bgt_thread);
749 ubi_devices[ubi->ubi_num] = ubi;
759 vfree(ubi->peb_buf1);
760 vfree(ubi->peb_buf2);
761 #ifdef CONFIG_MTD_UBI_DEBUG
762 vfree(ubi->dbg_peb_buf);
769 * ubi_detach_mtd_dev - detach an MTD device.
770 * @ubi_num: UBI device number to detach from
771 * @anyway: detach MTD even if device reference count is not zero
773 * This function destroys an UBI device number @ubi_num and detaches the
774 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
775 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
778 * Note, the invocations of this function has to be serialized by the
779 * @ubi_devices_mutex.
781 int ubi_detach_mtd_dev(int ubi_num, int anyway)
783 struct ubi_device *ubi;
785 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
788 spin_lock(&ubi_devices_lock);
789 ubi = ubi_devices[ubi_num];
791 spin_lock(&ubi_devices_lock);
795 if (ubi->ref_count) {
797 spin_lock(&ubi_devices_lock);
800 /* This may only happen if there is a bug */
801 ubi_err("%s reference count %d, destroy anyway",
802 ubi->ubi_name, ubi->ref_count);
804 ubi_devices[ubi->ubi_num] = NULL;
805 spin_unlock(&ubi_devices_lock);
807 dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi->ubi_num);
810 * Before freeing anything, we have to stop the background thread to
811 * prevent it from doing anything on this device while we are freeing.
814 kthread_stop(ubi->bgt_thread);
820 put_mtd_device(ubi->mtd);
821 vfree(ubi->peb_buf1);
822 vfree(ubi->peb_buf2);
823 #ifdef CONFIG_MTD_UBI_DEBUG
824 vfree(ubi->dbg_peb_buf);
826 ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
832 * ltree_entry_ctor - lock tree entries slab cache constructor.
833 * @obj: the lock-tree entry to construct
834 * @cache: the lock tree entry slab cache
835 * @flags: constructor flags
837 static void ltree_entry_ctor(struct kmem_cache *cache, void *obj)
839 struct ubi_ltree_entry *le = obj;
842 init_rwsem(&le->mutex);
846 * find_mtd_device - open an MTD device by its name or number.
847 * @mtd_dev: name or number of the device
849 * This function tries to open and MTD device with name @mtd_dev, and if it
850 * fails, then it tries to interpret the @mtd_dev string as an ASCII-coded
851 * integer and open an MTD device with this number. Returns MTD device
852 * description object in case of success and a negative error code in case of
855 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
857 struct mtd_info *mtd;
859 mtd = get_mtd_device_nm(mtd_dev);
864 if (PTR_ERR(mtd) != -ENODEV)
868 * Probably this is not MTD device name but MTD device number -
871 mtd_num = simple_strtoul(mtd_dev, &endp, 0);
872 if (*endp != '\0' || mtd_dev == endp) {
873 ubi_err("incorrect MTD device: \"%s\"", mtd_dev);
874 return ERR_PTR(-ENODEV);
877 mtd = get_mtd_device(NULL, mtd_num);
885 static int __init ubi_init(void)
889 /* Ensure that EC and VID headers have correct size */
890 BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
891 BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
893 if (mtd_devs > UBI_MAX_DEVICES) {
894 printk(KERN_ERR "UBI error: too many MTD devices, "
895 "maximum is %d\n", UBI_MAX_DEVICES);
899 /* Create base sysfs directory and sysfs files */
900 ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
901 if (IS_ERR(ubi_class)) {
902 err = PTR_ERR(ubi_class);
903 printk(KERN_ERR "UBI error: cannot create UBI class\n");
907 err = class_create_file(ubi_class, &ubi_version);
909 printk(KERN_ERR "UBI error: cannot create sysfs file\n");
913 err = misc_register(&ubi_ctrl_cdev);
915 printk(KERN_ERR "UBI error: cannot register device\n");
919 ubi_ltree_slab = kmem_cache_create("ubi_ltree_slab",
920 sizeof(struct ubi_ltree_entry), 0,
921 0, <ree_entry_ctor);
925 ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
926 sizeof(struct ubi_wl_entry),
928 if (!ubi_wl_entry_slab)
931 /* Attach MTD devices */
932 for (i = 0; i < mtd_devs; i++) {
933 struct mtd_dev_param *p = &mtd_dev_param[i];
934 struct mtd_info *mtd;
938 mtd = open_mtd_device(p->name);
944 mutex_lock(&ubi_devices_mutex);
945 err = ubi_attach_mtd_dev(mtd, p->vid_hdr_offs, p->data_offs);
946 mutex_unlock(&ubi_devices_mutex);
949 printk(KERN_ERR "UBI error: cannot attach %s\n",
958 for (k = 0; k < i; k++)
959 if (ubi_devices[k]) {
960 mutex_lock(&ubi_devices_mutex);
961 ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
962 mutex_unlock(&ubi_devices_mutex);
964 kmem_cache_destroy(ubi_wl_entry_slab);
966 kmem_cache_destroy(ubi_ltree_slab);
968 misc_deregister(&ubi_ctrl_cdev);
970 class_remove_file(ubi_class, &ubi_version);
972 class_destroy(ubi_class);
974 printk(KERN_ERR "UBI error: cannot initialize UBI, error %d\n", err);
977 module_init(ubi_init);
979 static void __exit ubi_exit(void)
983 for (i = 0; i < UBI_MAX_DEVICES; i++)
984 if (ubi_devices[i]) {
985 mutex_lock(&ubi_devices_mutex);
986 ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
987 mutex_unlock(&ubi_devices_mutex);
989 kmem_cache_destroy(ubi_wl_entry_slab);
990 kmem_cache_destroy(ubi_ltree_slab);
991 misc_deregister(&ubi_ctrl_cdev);
992 class_remove_file(ubi_class, &ubi_version);
993 class_destroy(ubi_class);
995 module_exit(ubi_exit);
998 * bytes_str_to_int - convert a string representing number of bytes to an
1000 * @str: the string to convert
1002 * This function returns positive resulting integer in case of success and a
1003 * negative error code in case of failure.
1005 static int __init bytes_str_to_int(const char *str)
1008 unsigned long result;
1010 result = simple_strtoul(str, &endp, 0);
1011 if (str == endp || result < 0) {
1012 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1025 if (endp[1] == 'i' && (endp[2] == '\0' ||
1026 endp[2] == 'B' || endp[2] == 'b'))
1031 printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n",
1040 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1041 * @val: the parameter value to parse
1044 * This function returns zero in case of success and a negative error code in
1047 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1050 struct mtd_dev_param *p;
1051 char buf[MTD_PARAM_LEN_MAX];
1052 char *pbuf = &buf[0];
1053 char *tokens[3] = {NULL, NULL, NULL};
1058 if (mtd_devs == UBI_MAX_DEVICES) {
1059 printk(KERN_ERR "UBI error: too many parameters, max. is %d\n",
1064 len = strnlen(val, MTD_PARAM_LEN_MAX);
1065 if (len == MTD_PARAM_LEN_MAX) {
1066 printk(KERN_ERR "UBI error: parameter \"%s\" is too long, "
1067 "max. is %d\n", val, MTD_PARAM_LEN_MAX);
1072 printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - "
1079 /* Get rid of the final newline */
1080 if (buf[len - 1] == '\n')
1081 buf[len - 1] = '\0';
1083 for (i = 0; i < 3; i++)
1084 tokens[i] = strsep(&pbuf, ",");
1087 printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n",
1092 p = &mtd_dev_param[mtd_devs];
1093 strcpy(&p->name[0], tokens[0]);
1096 p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1098 p->data_offs = bytes_str_to_int(tokens[2]);
1100 if (p->vid_hdr_offs < 0)
1101 return p->vid_hdr_offs;
1102 if (p->data_offs < 0)
1103 return p->data_offs;
1109 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1110 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: "
1111 "mtd=<name|num>[,<vid_hdr_offs>,<data_offs>]. "
1112 "Multiple \"mtd\" parameters may be specified.\n"
1113 "MTD devices may be specified by their number or name. "
1114 "Optional \"vid_hdr_offs\" and \"data_offs\" parameters "
1115 "specify UBI VID header position and data starting "
1116 "position to be used by UBI.\n"
1117 "Example: mtd=content,1984,2048 mtd=4 - attach MTD device"
1118 "with name content using VID header offset 1984 and data "
1119 "start 2048, and MTD device number 4 using default "
1122 MODULE_VERSION(__stringify(UBI_VERSION));
1123 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1124 MODULE_AUTHOR("Artem Bityutskiy");
1125 MODULE_LICENSE("GPL");