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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) International Business Machines Corp., 20064 * Copyright (c) Nokia Corporation, 20075 *6 * Author: Artem Bityutskiy (Битюцкий Артём),7 *         Frank Haverkamp8 */9 10/*11 * This file includes UBI initialization and building of UBI devices.12 *13 * When UBI is initialized, it attaches all the MTD devices specified as the14 * module load parameters or the kernel boot parameters. If MTD devices were15 * specified, UBI does not attach any MTD device, but it is possible to do16 * later using the "UBI control device".17 */18 19#include <linux/err.h>20#include <linux/module.h>21#include <linux/moduleparam.h>22#include <linux/stringify.h>23#include <linux/namei.h>24#include <linux/stat.h>25#include <linux/miscdevice.h>26#include <linux/mtd/partitions.h>27#include <linux/log2.h>28#include <linux/kthread.h>29#include <linux/kernel.h>30#include <linux/of.h>31#include <linux/slab.h>32#include <linux/major.h>33#include "ubi.h"34 35/* Maximum length of the 'mtd=' parameter */36#define MTD_PARAM_LEN_MAX 6437 38/* Maximum number of comma-separated items in the 'mtd=' parameter */39#define MTD_PARAM_MAX_COUNT 640 41/* Maximum value for the number of bad PEBs per 1024 PEBs */42#define MAX_MTD_UBI_BEB_LIMIT 76843 44#ifdef CONFIG_MTD_UBI_MODULE45#define ubi_is_module() 146#else47#define ubi_is_module() 048#endif49 50/**51 * struct mtd_dev_param - MTD device parameter description data structure.52 * @name: MTD character device node path, MTD device name, or MTD device number53 *        string54 * @ubi_num: UBI number55 * @vid_hdr_offs: VID header offset56 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs57 * @enable_fm: enable fastmap when value is non-zero58 * @need_resv_pool: reserve pool->max_size pebs when value is none-zero59 */60struct mtd_dev_param {61	char name[MTD_PARAM_LEN_MAX];62	int ubi_num;63	int vid_hdr_offs;64	int max_beb_per1024;65	int enable_fm;66	int need_resv_pool;67};68 69/* Numbers of elements set in the @mtd_dev_param array */70static int mtd_devs;71 72/* MTD devices specification parameters */73static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];74#ifdef CONFIG_MTD_UBI_FASTMAP75/* UBI module parameter to enable fastmap automatically on non-fastmap images */76static bool fm_autoconvert;77static bool fm_debug;78#endif79 80/* Slab cache for wear-leveling entries */81struct kmem_cache *ubi_wl_entry_slab;82 83/* UBI control character device */84static struct miscdevice ubi_ctrl_cdev = {85	.minor = MISC_DYNAMIC_MINOR,86	.name = "ubi_ctrl",87	.fops = &ubi_ctrl_cdev_operations,88};89 90/* All UBI devices in system */91static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];92 93/* Serializes UBI devices creations and removals */94DEFINE_MUTEX(ubi_devices_mutex);95 96/* Protects @ubi_devices, @ubi->ref_count and @ubi->is_dead */97static DEFINE_SPINLOCK(ubi_devices_lock);98 99/* "Show" method for files in '/<sysfs>/class/ubi/' */100/* UBI version attribute ('/<sysfs>/class/ubi/version') */101static ssize_t version_show(const struct class *class, const struct class_attribute *attr,102			    char *buf)103{104	return sprintf(buf, "%d\n", UBI_VERSION);105}106static CLASS_ATTR_RO(version);107 108static struct attribute *ubi_class_attrs[] = {109	&class_attr_version.attr,110	NULL,111};112ATTRIBUTE_GROUPS(ubi_class);113 114/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */115const struct class ubi_class = {116	.name		= UBI_NAME_STR,117	.class_groups	= ubi_class_groups,118};119 120static ssize_t dev_attribute_show(struct device *dev,121				  struct device_attribute *attr, char *buf);122 123/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */124static struct device_attribute dev_eraseblock_size =125	__ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);126static struct device_attribute dev_avail_eraseblocks =127	__ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);128static struct device_attribute dev_total_eraseblocks =129	__ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);130static struct device_attribute dev_volumes_count =131	__ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);132static struct device_attribute dev_max_ec =133	__ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);134static struct device_attribute dev_reserved_for_bad =135	__ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);136static struct device_attribute dev_bad_peb_count =137	__ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);138static struct device_attribute dev_max_vol_count =139	__ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);140static struct device_attribute dev_min_io_size =141	__ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);142static struct device_attribute dev_bgt_enabled =143	__ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);144static struct device_attribute dev_mtd_num =145	__ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);146static struct device_attribute dev_ro_mode =147	__ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);148 149/**150 * ubi_volume_notify - send a volume change notification.151 * @ubi: UBI device description object152 * @vol: volume description object of the changed volume153 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)154 *155 * This is a helper function which notifies all subscribers about a volume156 * change event (creation, removal, re-sizing, re-naming, updating). Returns157 * zero in case of success and a negative error code in case of failure.158 */159int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)160{161	int ret;162	struct ubi_notification nt;163 164	ubi_do_get_device_info(ubi, &nt.di);165	ubi_do_get_volume_info(ubi, vol, &nt.vi);166 167	switch (ntype) {168	case UBI_VOLUME_ADDED:169	case UBI_VOLUME_REMOVED:170	case UBI_VOLUME_RESIZED:171	case UBI_VOLUME_RENAMED:172		ret = ubi_update_fastmap(ubi);173		if (ret)174			ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);175	}176 177	return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);178}179 180/**181 * ubi_notify_all - send a notification to all volumes.182 * @ubi: UBI device description object183 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)184 * @nb: the notifier to call185 *186 * This function walks all volumes of UBI device @ubi and sends the @ntype187 * notification for each volume. If @nb is %NULL, then all registered notifiers188 * are called, otherwise only the @nb notifier is called. Returns the number of189 * sent notifications.190 */191int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)192{193	struct ubi_notification nt;194	int i, count = 0;195 196	ubi_do_get_device_info(ubi, &nt.di);197 198	mutex_lock(&ubi->device_mutex);199	for (i = 0; i < ubi->vtbl_slots; i++) {200		/*201		 * Since the @ubi->device is locked, and we are not going to202		 * change @ubi->volumes, we do not have to lock203		 * @ubi->volumes_lock.204		 */205		if (!ubi->volumes[i])206			continue;207 208		ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);209		if (nb)210			nb->notifier_call(nb, ntype, &nt);211		else212			blocking_notifier_call_chain(&ubi_notifiers, ntype,213						     &nt);214		count += 1;215	}216	mutex_unlock(&ubi->device_mutex);217 218	return count;219}220 221/**222 * ubi_enumerate_volumes - send "add" notification for all existing volumes.223 * @nb: the notifier to call224 *225 * This function walks all UBI devices and volumes and sends the226 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all227 * registered notifiers are called, otherwise only the @nb notifier is called.228 * Returns the number of sent notifications.229 */230int ubi_enumerate_volumes(struct notifier_block *nb)231{232	int i, count = 0;233 234	/*235	 * Since the @ubi_devices_mutex is locked, and we are not going to236	 * change @ubi_devices, we do not have to lock @ubi_devices_lock.237	 */238	for (i = 0; i < UBI_MAX_DEVICES; i++) {239		struct ubi_device *ubi = ubi_devices[i];240 241		if (!ubi)242			continue;243		count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);244	}245 246	return count;247}248 249/**250 * ubi_get_device - get UBI device.251 * @ubi_num: UBI device number252 *253 * This function returns UBI device description object for UBI device number254 * @ubi_num, or %NULL if the device does not exist. This function increases the255 * device reference count to prevent removal of the device. In other words, the256 * device cannot be removed if its reference count is not zero.257 */258struct ubi_device *ubi_get_device(int ubi_num)259{260	struct ubi_device *ubi;261 262	spin_lock(&ubi_devices_lock);263	ubi = ubi_devices[ubi_num];264	if (ubi && ubi->is_dead)265		ubi = NULL;266 267	if (ubi) {268		ubi_assert(ubi->ref_count >= 0);269		ubi->ref_count += 1;270		get_device(&ubi->dev);271	}272	spin_unlock(&ubi_devices_lock);273 274	return ubi;275}276 277/**278 * ubi_put_device - drop an UBI device reference.279 * @ubi: UBI device description object280 */281void ubi_put_device(struct ubi_device *ubi)282{283	spin_lock(&ubi_devices_lock);284	ubi->ref_count -= 1;285	put_device(&ubi->dev);286	spin_unlock(&ubi_devices_lock);287}288 289/**290 * ubi_get_by_major - get UBI device by character device major number.291 * @major: major number292 *293 * This function is similar to 'ubi_get_device()', but it searches the device294 * by its major number.295 */296struct ubi_device *ubi_get_by_major(int major)297{298	int i;299	struct ubi_device *ubi;300 301	spin_lock(&ubi_devices_lock);302	for (i = 0; i < UBI_MAX_DEVICES; i++) {303		ubi = ubi_devices[i];304		if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) {305			ubi_assert(ubi->ref_count >= 0);306			ubi->ref_count += 1;307			get_device(&ubi->dev);308			spin_unlock(&ubi_devices_lock);309			return ubi;310		}311	}312	spin_unlock(&ubi_devices_lock);313 314	return NULL;315}316 317/**318 * ubi_major2num - get UBI device number by character device major number.319 * @major: major number320 *321 * This function searches UBI device number object by its major number. If UBI322 * device was not found, this function returns -ENODEV, otherwise the UBI device323 * number is returned.324 */325int ubi_major2num(int major)326{327	int i, ubi_num = -ENODEV;328 329	spin_lock(&ubi_devices_lock);330	for (i = 0; i < UBI_MAX_DEVICES; i++) {331		struct ubi_device *ubi = ubi_devices[i];332 333		if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) {334			ubi_num = ubi->ubi_num;335			break;336		}337	}338	spin_unlock(&ubi_devices_lock);339 340	return ubi_num;341}342 343/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */344static ssize_t dev_attribute_show(struct device *dev,345				  struct device_attribute *attr, char *buf)346{347	ssize_t ret;348	struct ubi_device *ubi;349 350	/*351	 * The below code looks weird, but it actually makes sense. We get the352	 * UBI device reference from the contained 'struct ubi_device'. But it353	 * is unclear if the device was removed or not yet. Indeed, if the354	 * device was removed before we increased its reference count,355	 * 'ubi_get_device()' will return -ENODEV and we fail.356	 *357	 * Remember, 'struct ubi_device' is freed in the release function, so358	 * we still can use 'ubi->ubi_num'.359	 */360	ubi = container_of(dev, struct ubi_device, dev);361 362	if (attr == &dev_eraseblock_size)363		ret = sprintf(buf, "%d\n", ubi->leb_size);364	else if (attr == &dev_avail_eraseblocks)365		ret = sprintf(buf, "%d\n", ubi->avail_pebs);366	else if (attr == &dev_total_eraseblocks)367		ret = sprintf(buf, "%d\n", ubi->good_peb_count);368	else if (attr == &dev_volumes_count)369		ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);370	else if (attr == &dev_max_ec)371		ret = sprintf(buf, "%d\n", ubi->max_ec);372	else if (attr == &dev_reserved_for_bad)373		ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);374	else if (attr == &dev_bad_peb_count)375		ret = sprintf(buf, "%d\n", ubi->bad_peb_count);376	else if (attr == &dev_max_vol_count)377		ret = sprintf(buf, "%d\n", ubi->vtbl_slots);378	else if (attr == &dev_min_io_size)379		ret = sprintf(buf, "%d\n", ubi->min_io_size);380	else if (attr == &dev_bgt_enabled)381		ret = sprintf(buf, "%d\n", ubi->thread_enabled);382	else if (attr == &dev_mtd_num)383		ret = sprintf(buf, "%d\n", ubi->mtd->index);384	else if (attr == &dev_ro_mode)385		ret = sprintf(buf, "%d\n", ubi->ro_mode);386	else387		ret = -EINVAL;388 389	return ret;390}391 392static struct attribute *ubi_dev_attrs[] = {393	&dev_eraseblock_size.attr,394	&dev_avail_eraseblocks.attr,395	&dev_total_eraseblocks.attr,396	&dev_volumes_count.attr,397	&dev_max_ec.attr,398	&dev_reserved_for_bad.attr,399	&dev_bad_peb_count.attr,400	&dev_max_vol_count.attr,401	&dev_min_io_size.attr,402	&dev_bgt_enabled.attr,403	&dev_mtd_num.attr,404	&dev_ro_mode.attr,405	NULL406};407ATTRIBUTE_GROUPS(ubi_dev);408 409static void dev_release(struct device *dev)410{411	struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);412 413	kfree(ubi);414}415 416/**417 * kill_volumes - destroy all user volumes.418 * @ubi: UBI device description object419 */420static void kill_volumes(struct ubi_device *ubi)421{422	int i;423 424	for (i = 0; i < ubi->vtbl_slots; i++)425		if (ubi->volumes[i])426			ubi_free_volume(ubi, ubi->volumes[i]);427}428 429/**430 * uif_init - initialize user interfaces for an UBI device.431 * @ubi: UBI device description object432 *433 * This function initializes various user interfaces for an UBI device. If the434 * initialization fails at an early stage, this function frees all the435 * resources it allocated, returns an error.436 *437 * This function returns zero in case of success and a negative error code in438 * case of failure.439 */440static int uif_init(struct ubi_device *ubi)441{442	int i, err;443	dev_t dev;444 445	sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);446 447	/*448	 * Major numbers for the UBI character devices are allocated449	 * dynamically. Major numbers of volume character devices are450	 * equivalent to ones of the corresponding UBI character device. Minor451	 * numbers of UBI character devices are 0, while minor numbers of452	 * volume character devices start from 1. Thus, we allocate one major453	 * number and ubi->vtbl_slots + 1 minor numbers.454	 */455	err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);456	if (err) {457		ubi_err(ubi, "cannot register UBI character devices");458		return err;459	}460 461	ubi->dev.devt = dev;462 463	ubi_assert(MINOR(dev) == 0);464	cdev_init(&ubi->cdev, &ubi_cdev_operations);465	dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));466	ubi->cdev.owner = THIS_MODULE;467 468	dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);469	err = cdev_device_add(&ubi->cdev, &ubi->dev);470	if (err)471		goto out_unreg;472 473	for (i = 0; i < ubi->vtbl_slots; i++)474		if (ubi->volumes[i]) {475			err = ubi_add_volume(ubi, ubi->volumes[i]);476			if (err) {477				ubi_err(ubi, "cannot add volume %d", i);478				ubi->volumes[i] = NULL;479				goto out_volumes;480			}481		}482 483	return 0;484 485out_volumes:486	kill_volumes(ubi);487	cdev_device_del(&ubi->cdev, &ubi->dev);488out_unreg:489	unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);490	ubi_err(ubi, "cannot initialize UBI %s, error %d",491		ubi->ubi_name, err);492	return err;493}494 495/**496 * uif_close - close user interfaces for an UBI device.497 * @ubi: UBI device description object498 *499 * Note, since this function un-registers UBI volume device objects (@vol->dev),500 * the memory allocated voe the volumes is freed as well (in the release501 * function).502 */503static void uif_close(struct ubi_device *ubi)504{505	kill_volumes(ubi);506	cdev_device_del(&ubi->cdev, &ubi->dev);507	unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);508}509 510/**511 * ubi_free_volumes_from - free volumes from specific index.512 * @ubi: UBI device description object513 * @from: the start index used for volume free.514 */515static void ubi_free_volumes_from(struct ubi_device *ubi, int from)516{517	int i;518 519	for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {520		if (!ubi->volumes[i] || ubi->volumes[i]->is_dead)521			continue;522		ubi_eba_replace_table(ubi->volumes[i], NULL);523		ubi_fastmap_destroy_checkmap(ubi->volumes[i]);524		kfree(ubi->volumes[i]);525		ubi->volumes[i] = NULL;526	}527}528 529/**530 * ubi_free_all_volumes - free all volumes.531 * @ubi: UBI device description object532 */533void ubi_free_all_volumes(struct ubi_device *ubi)534{535	ubi_free_volumes_from(ubi, 0);536}537 538/**539 * ubi_free_internal_volumes - free internal volumes.540 * @ubi: UBI device description object541 */542void ubi_free_internal_volumes(struct ubi_device *ubi)543{544	ubi_free_volumes_from(ubi, ubi->vtbl_slots);545}546 547static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)548{549	int limit, device_pebs;550	uint64_t device_size;551 552	if (!max_beb_per1024) {553		/*554		 * Since max_beb_per1024 has not been set by the user in either555		 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the556		 * limit if it is supported by the device.557		 */558		limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size);559		if (limit < 0)560			return 0;561		return limit;562	}563 564	/*565	 * Here we are using size of the entire flash chip and566	 * not just the MTD partition size because the maximum567	 * number of bad eraseblocks is a percentage of the568	 * whole device and bad eraseblocks are not fairly569	 * distributed over the flash chip. So the worst case570	 * is that all the bad eraseblocks of the chip are in571	 * the MTD partition we are attaching (ubi->mtd).572	 */573	device_size = mtd_get_device_size(ubi->mtd);574	device_pebs = mtd_div_by_eb(device_size, ubi->mtd);575	limit = mult_frac(device_pebs, max_beb_per1024, 1024);576 577	/* Round it up */578	if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)579		limit += 1;580 581	return limit;582}583 584/**585 * io_init - initialize I/O sub-system for a given UBI device.586 * @ubi: UBI device description object587 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs588 *589 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are590 * assumed:591 *   o EC header is always at offset zero - this cannot be changed;592 *   o VID header starts just after the EC header at the closest address593 *     aligned to @io->hdrs_min_io_size;594 *   o data starts just after the VID header at the closest address aligned to595 *     @io->min_io_size596 *597 * This function returns zero in case of success and a negative error code in598 * case of failure.599 */600static int io_init(struct ubi_device *ubi, int max_beb_per1024)601{602	dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));603	dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));604 605	if (ubi->mtd->numeraseregions != 0) {606		/*607		 * Some flashes have several erase regions. Different regions608		 * may have different eraseblock size and other609		 * characteristics. It looks like mostly multi-region flashes610		 * have one "main" region and one or more small regions to611		 * store boot loader code or boot parameters or whatever. I612		 * guess we should just pick the largest region. But this is613		 * not implemented.614		 */615		ubi_err(ubi, "multiple regions, not implemented");616		return -EINVAL;617	}618 619	if (ubi->vid_hdr_offset < 0)620		return -EINVAL;621 622	/*623	 * Note, in this implementation we support MTD devices with 0x7FFFFFFF624	 * physical eraseblocks maximum.625	 */626 627	ubi->peb_size   = ubi->mtd->erasesize;628	ubi->peb_count  = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);629	ubi->flash_size = ubi->mtd->size;630 631	if (mtd_can_have_bb(ubi->mtd)) {632		ubi->bad_allowed = 1;633		ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);634	}635 636	if (ubi->mtd->type == MTD_NORFLASH)637		ubi->nor_flash = 1;638 639	ubi->min_io_size = ubi->mtd->writesize;640	ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;641 642	/*643	 * Make sure minimal I/O unit is power of 2. Note, there is no644	 * fundamental reason for this assumption. It is just an optimization645	 * which allows us to avoid costly division operations.646	 */647	if (!is_power_of_2(ubi->min_io_size)) {648		ubi_err(ubi, "min. I/O unit (%d) is not power of 2",649			ubi->min_io_size);650		return -EINVAL;651	}652 653	ubi_assert(ubi->hdrs_min_io_size > 0);654	ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);655	ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);656 657	ubi->max_write_size = ubi->mtd->writebufsize;658	/*659	 * Maximum write size has to be greater or equivalent to min. I/O660	 * size, and be multiple of min. I/O size.661	 */662	if (ubi->max_write_size < ubi->min_io_size ||663	    ubi->max_write_size % ubi->min_io_size ||664	    !is_power_of_2(ubi->max_write_size)) {665		ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",666			ubi->max_write_size, ubi->min_io_size);667		return -EINVAL;668	}669 670	/* Calculate default aligned sizes of EC and VID headers */671	ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);672	ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);673 674	dbg_gen("min_io_size      %d", ubi->min_io_size);675	dbg_gen("max_write_size   %d", ubi->max_write_size);676	dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);677	dbg_gen("ec_hdr_alsize    %d", ubi->ec_hdr_alsize);678	dbg_gen("vid_hdr_alsize   %d", ubi->vid_hdr_alsize);679 680	if (ubi->vid_hdr_offset == 0)681		/* Default offset */682		ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =683				      ubi->ec_hdr_alsize;684	else {685		ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &686						~(ubi->hdrs_min_io_size - 1);687		ubi->vid_hdr_shift = ubi->vid_hdr_offset -688						ubi->vid_hdr_aloffset;689	}690 691	/*692	 * Memory allocation for VID header is ubi->vid_hdr_alsize693	 * which is described in comments in io.c.694	 * Make sure VID header shift + UBI_VID_HDR_SIZE not exceeds695	 * ubi->vid_hdr_alsize, so that all vid header operations696	 * won't access memory out of bounds.697	 */698	if ((ubi->vid_hdr_shift + UBI_VID_HDR_SIZE) > ubi->vid_hdr_alsize) {699		ubi_err(ubi, "Invalid VID header offset %d, VID header shift(%d)"700			" + VID header size(%zu) > VID header aligned size(%d).",701			ubi->vid_hdr_offset, ubi->vid_hdr_shift,702			UBI_VID_HDR_SIZE, ubi->vid_hdr_alsize);703		return -EINVAL;704	}705 706	/* Similar for the data offset */707	ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;708	ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);709 710	dbg_gen("vid_hdr_offset   %d", ubi->vid_hdr_offset);711	dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);712	dbg_gen("vid_hdr_shift    %d", ubi->vid_hdr_shift);713	dbg_gen("leb_start        %d", ubi->leb_start);714 715	/* The shift must be aligned to 32-bit boundary */716	if (ubi->vid_hdr_shift % 4) {717		ubi_err(ubi, "unaligned VID header shift %d",718			ubi->vid_hdr_shift);719		return -EINVAL;720	}721 722	/* Check sanity */723	if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||724	    ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||725	    ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||726	    ubi->leb_start & (ubi->min_io_size - 1)) {727		ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",728			ubi->vid_hdr_offset, ubi->leb_start);729		return -EINVAL;730	}731 732	/*733	 * Set maximum amount of physical erroneous eraseblocks to be 10%.734	 * Erroneous PEB are those which have read errors.735	 */736	ubi->max_erroneous = ubi->peb_count / 10;737	if (ubi->max_erroneous < 16)738		ubi->max_erroneous = 16;739	dbg_gen("max_erroneous    %d", ubi->max_erroneous);740 741	/*742	 * It may happen that EC and VID headers are situated in one minimal743	 * I/O unit. In this case we can only accept this UBI image in744	 * read-only mode.745	 */746	if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {747		ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");748		ubi->ro_mode = 1;749	}750 751	ubi->leb_size = ubi->peb_size - ubi->leb_start;752 753	if (!(ubi->mtd->flags & MTD_WRITEABLE)) {754		ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",755			ubi->mtd->index);756		ubi->ro_mode = 1;757	}758 759	/*760	 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But761	 * unfortunately, MTD does not provide this information. We should loop762	 * over all physical eraseblocks and invoke mtd->block_is_bad() for763	 * each physical eraseblock. So, we leave @ubi->bad_peb_count764	 * uninitialized so far.765	 */766 767	return 0;768}769 770/**771 * autoresize - re-size the volume which has the "auto-resize" flag set.772 * @ubi: UBI device description object773 * @vol_id: ID of the volume to re-size774 *775 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in776 * the volume table to the largest possible size. See comments in ubi-header.h777 * for more description of the flag. Returns zero in case of success and a778 * negative error code in case of failure.779 */780static int autoresize(struct ubi_device *ubi, int vol_id)781{782	struct ubi_volume_desc desc;783	struct ubi_volume *vol = ubi->volumes[vol_id];784	int err, old_reserved_pebs = vol->reserved_pebs;785 786	if (ubi->ro_mode) {787		ubi_warn(ubi, "skip auto-resize because of R/O mode");788		return 0;789	}790 791	/*792	 * Clear the auto-resize flag in the volume in-memory copy of the793	 * volume table, and 'ubi_resize_volume()' will propagate this change794	 * to the flash.795	 */796	ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;797 798	if (ubi->avail_pebs == 0) {799		struct ubi_vtbl_record vtbl_rec;800 801		/*802		 * No available PEBs to re-size the volume, clear the flag on803		 * flash and exit.804		 */805		vtbl_rec = ubi->vtbl[vol_id];806		err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);807		if (err)808			ubi_err(ubi, "cannot clean auto-resize flag for volume %d",809				vol_id);810	} else {811		desc.vol = vol;812		err = ubi_resize_volume(&desc,813					old_reserved_pebs + ubi->avail_pebs);814		if (err)815			ubi_err(ubi, "cannot auto-resize volume %d",816				vol_id);817	}818 819	if (err)820		return err;821 822	ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",823		vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);824	return 0;825}826 827/**828 * ubi_attach_mtd_dev - attach an MTD device.829 * @mtd: MTD device description object830 * @ubi_num: number to assign to the new UBI device831 * @vid_hdr_offset: VID header offset832 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs833 * @disable_fm: whether disable fastmap834 * @need_resv_pool: whether reserve pebs to fill fm_pool835 *836 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number837 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in838 * which case this function finds a vacant device number and assigns it839 * automatically. Returns the new UBI device number in case of success and a840 * negative error code in case of failure.841 *842 * If @disable_fm is true, ubi doesn't create new fastmap even the module param843 * 'fm_autoconvert' is set, and existed old fastmap will be destroyed after844 * doing full scanning.845 *846 * Note, the invocations of this function has to be serialized by the847 * @ubi_devices_mutex.848 */849int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,850		       int vid_hdr_offset, int max_beb_per1024, bool disable_fm,851		       bool need_resv_pool)852{853	struct ubi_device *ubi;854	int i, err;855 856	if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)857		return -EINVAL;858 859	if (!max_beb_per1024)860		max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;861 862	/*863	 * Check if we already have the same MTD device attached.864	 *865	 * Note, this function assumes that UBI devices creations and deletions866	 * are serialized, so it does not take the &ubi_devices_lock.867	 */868	for (i = 0; i < UBI_MAX_DEVICES; i++) {869		ubi = ubi_devices[i];870		if (ubi && mtd->index == ubi->mtd->index) {871			pr_err("ubi: mtd%d is already attached to ubi%d\n",872				mtd->index, i);873			return -EEXIST;874		}875	}876 877	/*878	 * Make sure this MTD device is not emulated on top of an UBI volume879	 * already. Well, generally this recursion works fine, but there are880	 * different problems like the UBI module takes a reference to itself881	 * by attaching (and thus, opening) the emulated MTD device. This882	 * results in inability to unload the module. And in general it makes883	 * no sense to attach emulated MTD devices, so we prohibit this.884	 */885	if (mtd->type == MTD_UBIVOLUME) {886		pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",887			mtd->index);888		return -EINVAL;889	}890 891	/*892	 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.893	 * MLC NAND is different and needs special care, otherwise UBI or UBIFS894	 * will die soon and you will lose all your data.895	 * Relax this rule if the partition we're attaching to operates in SLC896	 * mode.897	 */898	if (mtd->type == MTD_MLCNANDFLASH &&899	    !(mtd->flags & MTD_SLC_ON_MLC_EMULATION)) {900		pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",901			mtd->index);902		return -EINVAL;903	}904 905	/* UBI cannot work on flashes with zero erasesize. */906	if (!mtd->erasesize) {907		pr_err("ubi: refuse attaching mtd%d - zero erasesize flash is not supported\n",908			mtd->index);909		return -EINVAL;910	}911 912	if (ubi_num == UBI_DEV_NUM_AUTO) {913		/* Search for an empty slot in the @ubi_devices array */914		for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)915			if (!ubi_devices[ubi_num])916				break;917		if (ubi_num == UBI_MAX_DEVICES) {918			pr_err("ubi: only %d UBI devices may be created\n",919				UBI_MAX_DEVICES);920			return -ENFILE;921		}922	} else {923		if (ubi_num >= UBI_MAX_DEVICES)924			return -EINVAL;925 926		/* Make sure ubi_num is not busy */927		if (ubi_devices[ubi_num]) {928			pr_err("ubi: ubi%i already exists\n", ubi_num);929			return -EEXIST;930		}931	}932 933	ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);934	if (!ubi)935		return -ENOMEM;936 937	device_initialize(&ubi->dev);938	ubi->dev.release = dev_release;939	ubi->dev.class = &ubi_class;940	ubi->dev.groups = ubi_dev_groups;941	ubi->dev.parent = &mtd->dev;942 943	ubi->mtd = mtd;944	ubi->ubi_num = ubi_num;945	ubi->vid_hdr_offset = vid_hdr_offset;946	ubi->autoresize_vol_id = -1;947 948#ifdef CONFIG_MTD_UBI_FASTMAP949	ubi->fm_pool.used = ubi->fm_pool.size = 0;950	ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;951 952	/*953	 * fm_pool.max_size is 5% of the total number of PEBs but it's also954	 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.955	 */956	ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,957		ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);958	ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,959		UBI_FM_MIN_POOL_SIZE);960 961	ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;962	ubi->fm_pool_rsv_cnt = need_resv_pool ? ubi->fm_pool.max_size : 0;963	ubi->fm_disabled = (!fm_autoconvert || disable_fm) ? 1 : 0;964	if (fm_debug)965		ubi_enable_dbg_chk_fastmap(ubi);966 967	if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)968	    <= UBI_FM_MAX_START) {969		ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",970			UBI_FM_MAX_START);971		ubi->fm_disabled = 1;972	}973 974	ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);975	ubi_msg(ubi, "default fastmap WL pool size: %d",976		ubi->fm_wl_pool.max_size);977#else978	ubi->fm_disabled = 1;979#endif980	mutex_init(&ubi->buf_mutex);981	mutex_init(&ubi->ckvol_mutex);982	mutex_init(&ubi->device_mutex);983	spin_lock_init(&ubi->volumes_lock);984	init_rwsem(&ubi->fm_protect);985	init_rwsem(&ubi->fm_eba_sem);986 987	ubi_msg(ubi, "attaching mtd%d", mtd->index);988 989	err = io_init(ubi, max_beb_per1024);990	if (err)991		goto out_free;992 993	err = -ENOMEM;994	ubi->peb_buf = vmalloc(ubi->peb_size);995	if (!ubi->peb_buf)996		goto out_free;997 998#ifdef CONFIG_MTD_UBI_FASTMAP999	ubi->fm_size = ubi_calc_fm_size(ubi);1000	ubi->fm_buf = vzalloc(ubi->fm_size);1001	if (!ubi->fm_buf)1002		goto out_free;1003#endif1004	err = ubi_attach(ubi, disable_fm ? 1 : 0);1005	if (err) {1006		ubi_err(ubi, "failed to attach mtd%d, error %d",1007			mtd->index, err);1008		goto out_free;1009	}1010 1011	if (ubi->autoresize_vol_id != -1) {1012		err = autoresize(ubi, ubi->autoresize_vol_id);1013		if (err)1014			goto out_detach;1015	}1016 1017	err = uif_init(ubi);1018	if (err)1019		goto out_detach;1020 1021	err = ubi_debugfs_init_dev(ubi);1022	if (err)1023		goto out_uif;1024 1025	ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);1026	if (IS_ERR(ubi->bgt_thread)) {1027		err = PTR_ERR(ubi->bgt_thread);1028		ubi_err(ubi, "cannot spawn \"%s\", error %d",1029			ubi->bgt_name, err);1030		goto out_debugfs;1031	}1032 1033	ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",1034		mtd->index, mtd->name, ubi->flash_size >> 20);1035	ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",1036		ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);1037	ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",1038		ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);1039	ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",1040		ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);1041	ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",1042		ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);1043	ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",1044		ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,1045		ubi->vtbl_slots);1046	ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",1047		ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,1048		ubi->image_seq);1049	ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",1050		ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);1051 1052	/*1053	 * The below lock makes sure we do not race with 'ubi_thread()' which1054	 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.1055	 */1056	spin_lock(&ubi->wl_lock);1057	ubi->thread_enabled = 1;1058	wake_up_process(ubi->bgt_thread);1059	spin_unlock(&ubi->wl_lock);1060 1061	ubi_devices[ubi_num] = ubi;1062	ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);1063	return ubi_num;1064 1065out_debugfs:1066	ubi_debugfs_exit_dev(ubi);1067out_uif:1068	uif_close(ubi);1069out_detach:1070	ubi_wl_close(ubi);1071	ubi_free_all_volumes(ubi);1072	vfree(ubi->vtbl);1073out_free:1074	vfree(ubi->peb_buf);1075	vfree(ubi->fm_buf);1076	put_device(&ubi->dev);1077	return err;1078}1079 1080/**1081 * ubi_detach_mtd_dev - detach an MTD device.1082 * @ubi_num: UBI device number to detach from1083 * @anyway: detach MTD even if device reference count is not zero1084 *1085 * This function destroys an UBI device number @ubi_num and detaches the1086 * underlying MTD device. Returns zero in case of success and %-EBUSY if the1087 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not1088 * exist.1089 *1090 * Note, the invocations of this function has to be serialized by the1091 * @ubi_devices_mutex.1092 */1093int ubi_detach_mtd_dev(int ubi_num, int anyway)1094{1095	struct ubi_device *ubi;1096 1097	if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)1098		return -EINVAL;1099 1100	ubi = ubi_get_device(ubi_num);1101	if (!ubi)1102		return -EINVAL;1103 1104	spin_lock(&ubi_devices_lock);1105	ubi->ref_count -= 1;1106	if (ubi->ref_count) {1107		if (!anyway) {1108			spin_unlock(&ubi_devices_lock);1109			return -EBUSY;1110		}1111		/* This may only happen if there is a bug */1112		ubi_err(ubi, "%s reference count %d, destroy anyway",1113			ubi->ubi_name, ubi->ref_count);1114	}1115	ubi->is_dead = true;1116	spin_unlock(&ubi_devices_lock);1117 1118	ubi_notify_all(ubi, UBI_VOLUME_SHUTDOWN, NULL);1119 1120	spin_lock(&ubi_devices_lock);1121	put_device(&ubi->dev);1122	ubi_devices[ubi_num] = NULL;1123	spin_unlock(&ubi_devices_lock);1124 1125	ubi_assert(ubi_num == ubi->ubi_num);1126	ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);1127	ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);1128#ifdef CONFIG_MTD_UBI_FASTMAP1129	/* If we don't write a new fastmap at detach time we lose all1130	 * EC updates that have been made since the last written fastmap.1131	 * In case of fastmap debugging we omit the update to simulate an1132	 * unclean shutdown. */1133	if (!ubi_dbg_chk_fastmap(ubi))1134		ubi_update_fastmap(ubi);1135#endif1136	/*1137	 * Before freeing anything, we have to stop the background thread to1138	 * prevent it from doing anything on this device while we are freeing.1139	 */1140	if (ubi->bgt_thread)1141		kthread_stop(ubi->bgt_thread);1142 1143#ifdef CONFIG_MTD_UBI_FASTMAP1144	cancel_work_sync(&ubi->fm_work);1145#endif1146	ubi_debugfs_exit_dev(ubi);1147	uif_close(ubi);1148 1149	ubi_wl_close(ubi);1150	ubi_free_internal_volumes(ubi);1151	vfree(ubi->vtbl);1152	vfree(ubi->peb_buf);1153	vfree(ubi->fm_buf);1154	ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);1155	put_mtd_device(ubi->mtd);1156	put_device(&ubi->dev);1157	return 0;1158}1159 1160/**1161 * open_mtd_by_chdev - open an MTD device by its character device node path.1162 * @mtd_dev: MTD character device node path1163 *1164 * This helper function opens an MTD device by its character node device path.1165 * Returns MTD device description object in case of success and a negative1166 * error code in case of failure.1167 */1168static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)1169{1170	int err, minor;1171	struct path path;1172	struct kstat stat;1173 1174	/* Probably this is an MTD character device node path */1175	err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);1176	if (err)1177		return ERR_PTR(err);1178 1179	err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);1180	path_put(&path);1181	if (err)1182		return ERR_PTR(err);1183 1184	/* MTD device number is defined by the major / minor numbers */1185	if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))1186		return ERR_PTR(-EINVAL);1187 1188	minor = MINOR(stat.rdev);1189 1190	if (minor & 1)1191		/*1192		 * Just do not think the "/dev/mtdrX" devices support is need,1193		 * so do not support them to avoid doing extra work.1194		 */1195		return ERR_PTR(-EINVAL);1196 1197	return get_mtd_device(NULL, minor / 2);1198}1199 1200/**1201 * open_mtd_device - open MTD device by name, character device path, or number.1202 * @mtd_dev: name, character device node path, or MTD device device number1203 *1204 * This function tries to open and MTD device described by @mtd_dev string,1205 * which is first treated as ASCII MTD device number, and if it is not true, it1206 * is treated as MTD device name, and if that is also not true, it is treated1207 * as MTD character device node path. Returns MTD device description object in1208 * case of success and a negative error code in case of failure.1209 */1210static struct mtd_info * __init open_mtd_device(const char *mtd_dev)1211{1212	struct mtd_info *mtd;1213	int mtd_num;1214	char *endp;1215 1216	mtd_num = simple_strtoul(mtd_dev, &endp, 0);1217	if (*endp != '\0' || mtd_dev == endp) {1218		/*1219		 * This does not look like an ASCII integer, probably this is1220		 * MTD device name.1221		 */1222		mtd = get_mtd_device_nm(mtd_dev);1223		if (PTR_ERR(mtd) == -ENODEV)1224			/* Probably this is an MTD character device node path */1225			mtd = open_mtd_by_chdev(mtd_dev);1226	} else1227		mtd = get_mtd_device(NULL, mtd_num);1228 1229	return mtd;1230}1231 1232static void ubi_notify_add(struct mtd_info *mtd)1233{1234	struct device_node *np = mtd_get_of_node(mtd);1235	int err;1236 1237	if (!of_device_is_compatible(np, "linux,ubi"))1238		return;1239 1240	/*1241	 * we are already holding &mtd_table_mutex, but still need1242	 * to bump refcount1243	 */1244	err = __get_mtd_device(mtd);1245	if (err)1246		return;1247 1248	/* called while holding mtd_table_mutex */1249	mutex_lock_nested(&ubi_devices_mutex, SINGLE_DEPTH_NESTING);1250	err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0, false, false);1251	mutex_unlock(&ubi_devices_mutex);1252	if (err < 0)1253		__put_mtd_device(mtd);1254}1255 1256static void ubi_notify_remove(struct mtd_info *mtd)1257{1258	/* do nothing for now */1259}1260 1261static struct mtd_notifier ubi_mtd_notifier = {1262	.add = ubi_notify_add,1263	.remove = ubi_notify_remove,1264};1265 1266static int __init ubi_init_attach(void)1267{1268	int err, i, k;1269 1270	/* Attach MTD devices */1271	for (i = 0; i < mtd_devs; i++) {1272		struct mtd_dev_param *p = &mtd_dev_param[i];1273		struct mtd_info *mtd;1274 1275		cond_resched();1276 1277		mtd = open_mtd_device(p->name);1278		if (IS_ERR(mtd)) {1279			err = PTR_ERR(mtd);1280			pr_err("UBI error: cannot open mtd %s, error %d\n",1281			       p->name, err);1282			/* See comment below re-ubi_is_module(). */1283			if (ubi_is_module())1284				goto out_detach;1285			continue;1286		}1287 1288		mutex_lock(&ubi_devices_mutex);1289		err = ubi_attach_mtd_dev(mtd, p->ubi_num,1290					 p->vid_hdr_offs, p->max_beb_per1024,1291					 p->enable_fm == 0,1292					 p->need_resv_pool != 0);1293		mutex_unlock(&ubi_devices_mutex);1294		if (err < 0) {1295			pr_err("UBI error: cannot attach mtd%d\n",1296			       mtd->index);1297			put_mtd_device(mtd);1298 1299			/*1300			 * Originally UBI stopped initializing on any error.1301			 * However, later on it was found out that this1302			 * behavior is not very good when UBI is compiled into1303			 * the kernel and the MTD devices to attach are passed1304			 * through the command line. Indeed, UBI failure1305			 * stopped whole boot sequence.1306			 *1307			 * To fix this, we changed the behavior for the1308			 * non-module case, but preserved the old behavior for1309			 * the module case, just for compatibility. This is a1310			 * little inconsistent, though.1311			 */1312			if (ubi_is_module())1313				goto out_detach;1314		}1315	}1316 1317	return 0;1318 1319out_detach:1320	for (k = 0; k < i; k++)1321		if (ubi_devices[k]) {1322			mutex_lock(&ubi_devices_mutex);1323			ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);1324			mutex_unlock(&ubi_devices_mutex);1325		}1326	return err;1327}1328#ifndef CONFIG_MTD_UBI_MODULE1329late_initcall(ubi_init_attach);1330#endif1331 1332static int __init ubi_init(void)1333{1334	int err;1335 1336	/* Ensure that EC and VID headers have correct size */1337	BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);1338	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);1339 1340	if (mtd_devs > UBI_MAX_DEVICES) {1341		pr_err("UBI error: too many MTD devices, maximum is %d\n",1342		       UBI_MAX_DEVICES);1343		return -EINVAL;1344	}1345 1346	/* Create base sysfs directory and sysfs files */1347	err = class_register(&ubi_class);1348	if (err < 0)1349		return err;1350 1351	err = misc_register(&ubi_ctrl_cdev);1352	if (err) {1353		pr_err("UBI error: cannot register device\n");1354		goto out;1355	}1356 1357	ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",1358					      sizeof(struct ubi_wl_entry),1359					      0, 0, NULL);1360	if (!ubi_wl_entry_slab) {1361		err = -ENOMEM;1362		goto out_dev_unreg;1363	}1364 1365	err = ubi_debugfs_init();1366	if (err)1367		goto out_slab;1368 1369	err = ubiblock_init();1370	if (err) {1371		pr_err("UBI error: block: cannot initialize, error %d\n", err);1372 1373		/* See comment above re-ubi_is_module(). */1374		if (ubi_is_module())1375			goto out_debugfs;1376	}1377 1378	register_mtd_user(&ubi_mtd_notifier);1379 1380	if (ubi_is_module()) {1381		err = ubi_init_attach();1382		if (err)1383			goto out_mtd_notifier;1384	}1385 1386	return 0;1387 1388out_mtd_notifier:1389	unregister_mtd_user(&ubi_mtd_notifier);1390	ubiblock_exit();1391out_debugfs:1392	ubi_debugfs_exit();1393out_slab:1394	kmem_cache_destroy(ubi_wl_entry_slab);1395out_dev_unreg:1396	misc_deregister(&ubi_ctrl_cdev);1397out:1398	class_unregister(&ubi_class);1399	pr_err("UBI error: cannot initialize UBI, error %d\n", err);1400	return err;1401}1402device_initcall(ubi_init);1403 1404 1405static void __exit ubi_exit(void)1406{1407	int i;1408 1409	ubiblock_exit();1410	unregister_mtd_user(&ubi_mtd_notifier);1411 1412	for (i = 0; i < UBI_MAX_DEVICES; i++)1413		if (ubi_devices[i]) {1414			mutex_lock(&ubi_devices_mutex);1415			ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);1416			mutex_unlock(&ubi_devices_mutex);1417		}1418	ubi_debugfs_exit();1419	kmem_cache_destroy(ubi_wl_entry_slab);1420	misc_deregister(&ubi_ctrl_cdev);1421	class_unregister(&ubi_class);1422}1423module_exit(ubi_exit);1424 1425/**1426 * bytes_str_to_int - convert a number of bytes string into an integer.1427 * @str: the string to convert1428 *1429 * This function returns positive resulting integer in case of success and a1430 * negative error code in case of failure.1431 */1432static int bytes_str_to_int(const char *str)1433{1434	char *endp;1435	unsigned long result;1436 1437	result = simple_strtoul(str, &endp, 0);1438	if (str == endp || result >= INT_MAX) {1439		pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);1440		return -EINVAL;1441	}1442 1443	switch (*endp) {1444	case 'G':1445		result *= 1024;1446		fallthrough;1447	case 'M':1448		result *= 1024;1449		fallthrough;1450	case 'K':1451		result *= 1024;1452		break;1453	case '\0':1454		break;1455	default:1456		pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);1457		return -EINVAL;1458	}1459 1460	return result;1461}1462 1463/**1464 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.1465 * @val: the parameter value to parse1466 * @kp: not used1467 *1468 * This function returns zero in case of success and a negative error code in1469 * case of error.1470 */1471static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)1472{1473	int i, len;1474	struct mtd_dev_param *p;1475	char buf[MTD_PARAM_LEN_MAX];1476	char *pbuf = &buf[0];1477	char *tokens[MTD_PARAM_MAX_COUNT], *token;1478 1479	if (!val)1480		return -EINVAL;1481 1482	if (mtd_devs == UBI_MAX_DEVICES) {1483		pr_err("UBI error: too many parameters, max. is %d\n",1484		       UBI_MAX_DEVICES);1485		return -EINVAL;1486	}1487 1488	len = strnlen(val, MTD_PARAM_LEN_MAX);1489	if (len == MTD_PARAM_LEN_MAX) {1490		pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",1491		       val, MTD_PARAM_LEN_MAX);1492		return -EINVAL;1493	}1494 1495	if (len == 0) {1496		pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");1497		return 0;1498	}1499 1500	strcpy(buf, val);1501 1502	/* Get rid of the final newline */1503	if (buf[len - 1] == '\n')1504		buf[len - 1] = '\0';1505 1506	for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)1507		tokens[i] = strsep(&pbuf, ",");1508 1509	if (pbuf) {1510		pr_err("UBI error: too many arguments at \"%s\"\n", val);1511		return -EINVAL;1512	}1513 1514	p = &mtd_dev_param[mtd_devs];1515	strcpy(&p->name[0], tokens[0]);1516 1517	token = tokens[1];1518	if (token) {1519		p->vid_hdr_offs = bytes_str_to_int(token);1520 1521		if (p->vid_hdr_offs < 0)1522			return p->vid_hdr_offs;1523	}1524 1525	token = tokens[2];1526	if (token) {1527		int err = kstrtoint(token, 10, &p->max_beb_per1024);1528 1529		if (err) {1530			pr_err("UBI error: bad value for max_beb_per1024 parameter: %s\n",1531			       token);1532			return -EINVAL;1533		}1534	}1535 1536	token = tokens[3];1537	if (token) {1538		int err = kstrtoint(token, 10, &p->ubi_num);1539 1540		if (err) {1541			pr_err("UBI error: bad value for ubi_num parameter: %s\n",1542			       token);1543			return -EINVAL;1544		}1545	} else1546		p->ubi_num = UBI_DEV_NUM_AUTO;1547 1548	token = tokens[4];1549	if (token) {1550		int err = kstrtoint(token, 10, &p->enable_fm);1551 1552		if (err) {1553			pr_err("UBI error: bad value for enable_fm parameter: %s\n",1554				token);1555			return -EINVAL;1556		}1557	} else1558		p->enable_fm = 0;1559 1560	token = tokens[5];1561	if (token) {1562		int err = kstrtoint(token, 10, &p->need_resv_pool);1563 1564		if (err) {1565			pr_err("UBI error: bad value for need_resv_pool parameter: %s\n",1566				token);1567			return -EINVAL;1568		}1569	} else1570		p->need_resv_pool = 0;1571 1572	mtd_devs += 1;1573	return 0;1574}1575 1576module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);1577MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"1578		      "Multiple \"mtd\" parameters may be specified.\n"1579		      "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"1580		      "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"1581		      "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("1582		      __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"1583		      "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"1584		      "Optional \"enable_fm\" parameter determines whether to enable fastmap during attach. If the value is non-zero, fastmap is enabled. Default value is 0.\n"1585		      "Optional \"need_resv_pool\" parameter determines whether to reserve pool->max_size pebs during attach. If the value is non-zero, peb reservation is enabled. Default value is 0.\n"1586		      "\n"1587		      "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"1588		      "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"1589		      "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n"1590		      "Example 4: mtd=/dev/mtd1,0,0,5 - attach MTD device /dev/mtd1 to UBI 5 and using default values for the other fields.\n"1591		      "example 5: mtd=1,0,0,5 mtd=2,0,0,6,1 - attach MTD device /dev/mtd1 to UBI 5 and disable fastmap; attach MTD device /dev/mtd2 to UBI 6 and enable fastmap.(only works when fastmap is enabled and fm_autoconvert=Y).\n"1592		      "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");1593#ifdef CONFIG_MTD_UBI_FASTMAP1594module_param(fm_autoconvert, bool, 0644);1595MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");1596module_param(fm_debug, bool, 0);1597MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");1598#endif1599MODULE_VERSION(__stringify(UBI_VERSION));1600MODULE_DESCRIPTION("UBI - Unsorted Block Images");1601MODULE_AUTHOR("Artem Bityutskiy");1602MODULE_LICENSE("GPL");1603