1/*
   2 * Copyright (c) International Business Machines Corp., 2006
   3 * Copyright (c) Nokia Corporation, 2007
   4 *
   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.
   9 *
  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.
  14 *
  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
  18 *
  19 * Author: Artem Bityutskiy (Битюцкий Артём),
  20 *         Frank Haverkamp
  21 */
  22
  23/*
  24 * This file includes UBI initialization and building of UBI devices.
  25 *
  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".
  30 */
  31
  32#include <linux/err.h>
  33#include <linux/module.h>
  34#include <linux/moduleparam.h>
  35#include <linux/stringify.h>
  36#include <linux/namei.h>
  37#include <linux/stat.h>
  38#include <linux/miscdevice.h>
  39#include <linux/mtd/partitions.h>
  40#include <linux/log2.h>
  41#include <linux/kthread.h>
  42#include <linux/kernel.h>
  43#include <linux/slab.h>
  44#include <linux/major.h>
  45#include "ubi.h"
  46
  47/* Maximum length of the 'mtd=' parameter */
  48#define MTD_PARAM_LEN_MAX 64
  49
  50/* Maximum number of comma-separated items in the 'mtd=' parameter */
  51#define MTD_PARAM_MAX_COUNT 4
  52
  53/* Maximum value for the number of bad PEBs per 1024 PEBs */
  54#define MAX_MTD_UBI_BEB_LIMIT 768
  55
  56#ifdef CONFIG_MTD_UBI_MODULE
  57#define ubi_is_module() 1
  58#else
  59#define ubi_is_module() 0
  60#endif
  61
  62/**
  63 * struct mtd_dev_param - MTD device parameter description data structure.
  64 * @name: MTD character device node path, MTD device name, or MTD device number
  65 *        string
 
  66 * @vid_hdr_offs: VID header offset
  67 * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
 
 
  68 */
  69struct mtd_dev_param {
  70	char name[MTD_PARAM_LEN_MAX];
  71	int ubi_num;
  72	int vid_hdr_offs;
  73	int max_beb_per1024;
 
 
  74};
  75
  76/* Numbers of elements set in the @mtd_dev_param array */
  77static int mtd_devs;
  78
  79/* MTD devices specification parameters */
  80static struct mtd_dev_param mtd_dev_param[UBI_MAX_DEVICES];
  81#ifdef CONFIG_MTD_UBI_FASTMAP
  82/* UBI module parameter to enable fastmap automatically on non-fastmap images */
  83static bool fm_autoconvert;
  84static bool fm_debug;
  85#endif
  86
  87/* Slab cache for wear-leveling entries */
  88struct kmem_cache *ubi_wl_entry_slab;
  89
  90/* UBI control character device */
  91static struct miscdevice ubi_ctrl_cdev = {
  92	.minor = MISC_DYNAMIC_MINOR,
  93	.name = "ubi_ctrl",
  94	.fops = &ubi_ctrl_cdev_operations,
  95};
  96
  97/* All UBI devices in system */
  98static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
  99
 100/* Serializes UBI devices creations and removals */
 101DEFINE_MUTEX(ubi_devices_mutex);
 102
 103/* Protects @ubi_devices and @ubi->ref_count */
 104static DEFINE_SPINLOCK(ubi_devices_lock);
 105
 106/* "Show" method for files in '/<sysfs>/class/ubi/' */
 107/* UBI version attribute ('/<sysfs>/class/ubi/version') */
 108static ssize_t version_show(struct class *class, struct class_attribute *attr,
 109			    char *buf)
 110{
 111	return sprintf(buf, "%d\n", UBI_VERSION);
 112}
 113static CLASS_ATTR_RO(version);
 114
 115static struct attribute *ubi_class_attrs[] = {
 116	&class_attr_version.attr,
 117	NULL,
 118};
 119ATTRIBUTE_GROUPS(ubi_class);
 120
 121/* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
 122struct class ubi_class = {
 123	.name		= UBI_NAME_STR,
 124	.owner		= THIS_MODULE,
 125	.class_groups	= ubi_class_groups,
 126};
 127
 128static ssize_t dev_attribute_show(struct device *dev,
 129				  struct device_attribute *attr, char *buf);
 130
 131/* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
 132static struct device_attribute dev_eraseblock_size =
 133	__ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
 134static struct device_attribute dev_avail_eraseblocks =
 135	__ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
 136static struct device_attribute dev_total_eraseblocks =
 137	__ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
 138static struct device_attribute dev_volumes_count =
 139	__ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
 140static struct device_attribute dev_max_ec =
 141	__ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
 142static struct device_attribute dev_reserved_for_bad =
 143	__ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
 144static struct device_attribute dev_bad_peb_count =
 145	__ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
 146static struct device_attribute dev_max_vol_count =
 147	__ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
 148static struct device_attribute dev_min_io_size =
 149	__ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
 150static struct device_attribute dev_bgt_enabled =
 151	__ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
 152static struct device_attribute dev_mtd_num =
 153	__ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
 154static struct device_attribute dev_ro_mode =
 155	__ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
 156
 157/**
 158 * ubi_volume_notify - send a volume change notification.
 159 * @ubi: UBI device description object
 160 * @vol: volume description object of the changed volume
 161 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
 162 *
 163 * This is a helper function which notifies all subscribers about a volume
 164 * change event (creation, removal, re-sizing, re-naming, updating). Returns
 165 * zero in case of success and a negative error code in case of failure.
 166 */
 167int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
 168{
 169	int ret;
 170	struct ubi_notification nt;
 171
 172	ubi_do_get_device_info(ubi, &nt.di);
 173	ubi_do_get_volume_info(ubi, vol, &nt.vi);
 174
 175	switch (ntype) {
 176	case UBI_VOLUME_ADDED:
 177	case UBI_VOLUME_REMOVED:
 178	case UBI_VOLUME_RESIZED:
 179	case UBI_VOLUME_RENAMED:
 180		ret = ubi_update_fastmap(ubi);
 181		if (ret)
 182			ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
 183	}
 184
 185	return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
 186}
 187
 188/**
 189 * ubi_notify_all - send a notification to all volumes.
 190 * @ubi: UBI device description object
 191 * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc)
 192 * @nb: the notifier to call
 193 *
 194 * This function walks all volumes of UBI device @ubi and sends the @ntype
 195 * notification for each volume. If @nb is %NULL, then all registered notifiers
 196 * are called, otherwise only the @nb notifier is called. Returns the number of
 197 * sent notifications.
 198 */
 199int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
 200{
 201	struct ubi_notification nt;
 202	int i, count = 0;
 203
 204	ubi_do_get_device_info(ubi, &nt.di);
 205
 206	mutex_lock(&ubi->device_mutex);
 207	for (i = 0; i < ubi->vtbl_slots; i++) {
 208		/*
 209		 * Since the @ubi->device is locked, and we are not going to
 210		 * change @ubi->volumes, we do not have to lock
 211		 * @ubi->volumes_lock.
 212		 */
 213		if (!ubi->volumes[i])
 214			continue;
 215
 216		ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
 217		if (nb)
 218			nb->notifier_call(nb, ntype, &nt);
 219		else
 220			blocking_notifier_call_chain(&ubi_notifiers, ntype,
 221						     &nt);
 222		count += 1;
 223	}
 224	mutex_unlock(&ubi->device_mutex);
 225
 226	return count;
 227}
 228
 229/**
 230 * ubi_enumerate_volumes - send "add" notification for all existing volumes.
 231 * @nb: the notifier to call
 232 *
 233 * This function walks all UBI devices and volumes and sends the
 234 * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all
 235 * registered notifiers are called, otherwise only the @nb notifier is called.
 236 * Returns the number of sent notifications.
 237 */
 238int ubi_enumerate_volumes(struct notifier_block *nb)
 239{
 240	int i, count = 0;
 241
 242	/*
 243	 * Since the @ubi_devices_mutex is locked, and we are not going to
 244	 * change @ubi_devices, we do not have to lock @ubi_devices_lock.
 245	 */
 246	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 247		struct ubi_device *ubi = ubi_devices[i];
 248
 249		if (!ubi)
 250			continue;
 251		count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
 252	}
 253
 254	return count;
 255}
 256
 257/**
 258 * ubi_get_device - get UBI device.
 259 * @ubi_num: UBI device number
 260 *
 261 * This function returns UBI device description object for UBI device number
 262 * @ubi_num, or %NULL if the device does not exist. This function increases the
 263 * device reference count to prevent removal of the device. In other words, the
 264 * device cannot be removed if its reference count is not zero.
 265 */
 266struct ubi_device *ubi_get_device(int ubi_num)
 267{
 268	struct ubi_device *ubi;
 269
 270	spin_lock(&ubi_devices_lock);
 271	ubi = ubi_devices[ubi_num];
 272	if (ubi) {
 273		ubi_assert(ubi->ref_count >= 0);
 274		ubi->ref_count += 1;
 275		get_device(&ubi->dev);
 276	}
 277	spin_unlock(&ubi_devices_lock);
 278
 279	return ubi;
 280}
 281
 282/**
 283 * ubi_put_device - drop an UBI device reference.
 284 * @ubi: UBI device description object
 285 */
 286void ubi_put_device(struct ubi_device *ubi)
 287{
 288	spin_lock(&ubi_devices_lock);
 289	ubi->ref_count -= 1;
 290	put_device(&ubi->dev);
 291	spin_unlock(&ubi_devices_lock);
 292}
 293
 294/**
 295 * ubi_get_by_major - get UBI device by character device major number.
 296 * @major: major number
 297 *
 298 * This function is similar to 'ubi_get_device()', but it searches the device
 299 * by its major number.
 300 */
 301struct ubi_device *ubi_get_by_major(int major)
 302{
 303	int i;
 304	struct ubi_device *ubi;
 305
 306	spin_lock(&ubi_devices_lock);
 307	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 308		ubi = ubi_devices[i];
 309		if (ubi && MAJOR(ubi->cdev.dev) == major) {
 310			ubi_assert(ubi->ref_count >= 0);
 311			ubi->ref_count += 1;
 312			get_device(&ubi->dev);
 313			spin_unlock(&ubi_devices_lock);
 314			return ubi;
 315		}
 316	}
 317	spin_unlock(&ubi_devices_lock);
 318
 319	return NULL;
 320}
 321
 322/**
 323 * ubi_major2num - get UBI device number by character device major number.
 324 * @major: major number
 325 *
 326 * This function searches UBI device number object by its major number. If UBI
 327 * device was not found, this function returns -ENODEV, otherwise the UBI device
 328 * number is returned.
 329 */
 330int ubi_major2num(int major)
 331{
 332	int i, ubi_num = -ENODEV;
 333
 334	spin_lock(&ubi_devices_lock);
 335	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 336		struct ubi_device *ubi = ubi_devices[i];
 337
 338		if (ubi && MAJOR(ubi->cdev.dev) == major) {
 339			ubi_num = ubi->ubi_num;
 340			break;
 341		}
 342	}
 343	spin_unlock(&ubi_devices_lock);
 344
 345	return ubi_num;
 346}
 347
 348/* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
 349static ssize_t dev_attribute_show(struct device *dev,
 350				  struct device_attribute *attr, char *buf)
 351{
 352	ssize_t ret;
 353	struct ubi_device *ubi;
 354
 355	/*
 356	 * The below code looks weird, but it actually makes sense. We get the
 357	 * UBI device reference from the contained 'struct ubi_device'. But it
 358	 * is unclear if the device was removed or not yet. Indeed, if the
 359	 * device was removed before we increased its reference count,
 360	 * 'ubi_get_device()' will return -ENODEV and we fail.
 361	 *
 362	 * Remember, 'struct ubi_device' is freed in the release function, so
 363	 * we still can use 'ubi->ubi_num'.
 364	 */
 365	ubi = container_of(dev, struct ubi_device, dev);
 366	ubi = ubi_get_device(ubi->ubi_num);
 367	if (!ubi)
 368		return -ENODEV;
 369
 370	if (attr == &dev_eraseblock_size)
 371		ret = sprintf(buf, "%d\n", ubi->leb_size);
 372	else if (attr == &dev_avail_eraseblocks)
 373		ret = sprintf(buf, "%d\n", ubi->avail_pebs);
 374	else if (attr == &dev_total_eraseblocks)
 375		ret = sprintf(buf, "%d\n", ubi->good_peb_count);
 376	else if (attr == &dev_volumes_count)
 377		ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
 378	else if (attr == &dev_max_ec)
 379		ret = sprintf(buf, "%d\n", ubi->max_ec);
 380	else if (attr == &dev_reserved_for_bad)
 381		ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
 382	else if (attr == &dev_bad_peb_count)
 383		ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
 384	else if (attr == &dev_max_vol_count)
 385		ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
 386	else if (attr == &dev_min_io_size)
 387		ret = sprintf(buf, "%d\n", ubi->min_io_size);
 388	else if (attr == &dev_bgt_enabled)
 389		ret = sprintf(buf, "%d\n", ubi->thread_enabled);
 390	else if (attr == &dev_mtd_num)
 391		ret = sprintf(buf, "%d\n", ubi->mtd->index);
 392	else if (attr == &dev_ro_mode)
 393		ret = sprintf(buf, "%d\n", ubi->ro_mode);
 394	else
 395		ret = -EINVAL;
 396
 397	ubi_put_device(ubi);
 398	return ret;
 399}
 400
 401static struct attribute *ubi_dev_attrs[] = {
 402	&dev_eraseblock_size.attr,
 403	&dev_avail_eraseblocks.attr,
 404	&dev_total_eraseblocks.attr,
 405	&dev_volumes_count.attr,
 406	&dev_max_ec.attr,
 407	&dev_reserved_for_bad.attr,
 408	&dev_bad_peb_count.attr,
 409	&dev_max_vol_count.attr,
 410	&dev_min_io_size.attr,
 411	&dev_bgt_enabled.attr,
 412	&dev_mtd_num.attr,
 413	&dev_ro_mode.attr,
 414	NULL
 415};
 416ATTRIBUTE_GROUPS(ubi_dev);
 417
 418static void dev_release(struct device *dev)
 419{
 420	struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
 421
 422	kfree(ubi);
 423}
 424
 425/**
 426 * kill_volumes - destroy all user volumes.
 427 * @ubi: UBI device description object
 428 */
 429static void kill_volumes(struct ubi_device *ubi)
 430{
 431	int i;
 432
 433	for (i = 0; i < ubi->vtbl_slots; i++)
 434		if (ubi->volumes[i])
 435			ubi_free_volume(ubi, ubi->volumes[i]);
 436}
 437
 438/**
 439 * uif_init - initialize user interfaces for an UBI device.
 440 * @ubi: UBI device description object
 441 *
 442 * This function initializes various user interfaces for an UBI device. If the
 443 * initialization fails at an early stage, this function frees all the
 444 * resources it allocated, returns an error.
 445 *
 446 * This function returns zero in case of success and a negative error code in
 447 * case of failure.
 448 */
 449static int uif_init(struct ubi_device *ubi)
 450{
 451	int i, err;
 452	dev_t dev;
 453
 454	sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
 455
 456	/*
 457	 * Major numbers for the UBI character devices are allocated
 458	 * dynamically. Major numbers of volume character devices are
 459	 * equivalent to ones of the corresponding UBI character device. Minor
 460	 * numbers of UBI character devices are 0, while minor numbers of
 461	 * volume character devices start from 1. Thus, we allocate one major
 462	 * number and ubi->vtbl_slots + 1 minor numbers.
 463	 */
 464	err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
 465	if (err) {
 466		ubi_err(ubi, "cannot register UBI character devices");
 467		return err;
 468	}
 469
 470	ubi->dev.devt = dev;
 471
 472	ubi_assert(MINOR(dev) == 0);
 473	cdev_init(&ubi->cdev, &ubi_cdev_operations);
 474	dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
 475	ubi->cdev.owner = THIS_MODULE;
 476
 477	dev_set_name(&ubi->dev, UBI_NAME_STR "%d", ubi->ubi_num);
 478	err = cdev_device_add(&ubi->cdev, &ubi->dev);
 479	if (err)
 480		goto out_unreg;
 481
 482	for (i = 0; i < ubi->vtbl_slots; i++)
 483		if (ubi->volumes[i]) {
 484			err = ubi_add_volume(ubi, ubi->volumes[i]);
 485			if (err) {
 486				ubi_err(ubi, "cannot add volume %d", i);
 
 487				goto out_volumes;
 488			}
 489		}
 490
 491	return 0;
 492
 493out_volumes:
 494	kill_volumes(ubi);
 495	cdev_device_del(&ubi->cdev, &ubi->dev);
 496out_unreg:
 497	unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
 498	ubi_err(ubi, "cannot initialize UBI %s, error %d",
 499		ubi->ubi_name, err);
 500	return err;
 501}
 502
 503/**
 504 * uif_close - close user interfaces for an UBI device.
 505 * @ubi: UBI device description object
 506 *
 507 * Note, since this function un-registers UBI volume device objects (@vol->dev),
 508 * the memory allocated voe the volumes is freed as well (in the release
 509 * function).
 510 */
 511static void uif_close(struct ubi_device *ubi)
 512{
 513	kill_volumes(ubi);
 514	cdev_device_del(&ubi->cdev, &ubi->dev);
 515	unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
 516}
 517
 518/**
 519 * ubi_free_internal_volumes - free internal volumes.
 520 * @ubi: UBI device description object
 
 521 */
 522void ubi_free_internal_volumes(struct ubi_device *ubi)
 523{
 524	int i;
 525
 526	for (i = ubi->vtbl_slots;
 527	     i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
 
 528		ubi_eba_replace_table(ubi->volumes[i], NULL);
 
 529		kfree(ubi->volumes[i]);
 
 530	}
 531}
 532
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 533static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
 534{
 535	int limit, device_pebs;
 536	uint64_t device_size;
 537
 538	if (!max_beb_per1024) {
 539		/*
 540		 * Since max_beb_per1024 has not been set by the user in either
 541		 * the cmdline or Kconfig, use mtd_max_bad_blocks to set the
 542		 * limit if it is supported by the device.
 543		 */
 544		limit = mtd_max_bad_blocks(ubi->mtd, 0, ubi->mtd->size);
 545		if (limit < 0)
 546			return 0;
 547		return limit;
 548	}
 549
 550	/*
 551	 * Here we are using size of the entire flash chip and
 552	 * not just the MTD partition size because the maximum
 553	 * number of bad eraseblocks is a percentage of the
 554	 * whole device and bad eraseblocks are not fairly
 555	 * distributed over the flash chip. So the worst case
 556	 * is that all the bad eraseblocks of the chip are in
 557	 * the MTD partition we are attaching (ubi->mtd).
 558	 */
 559	device_size = mtd_get_device_size(ubi->mtd);
 560	device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
 561	limit = mult_frac(device_pebs, max_beb_per1024, 1024);
 562
 563	/* Round it up */
 564	if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
 565		limit += 1;
 566
 567	return limit;
 568}
 569
 570/**
 571 * io_init - initialize I/O sub-system for a given UBI device.
 572 * @ubi: UBI device description object
 573 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
 574 *
 575 * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are
 576 * assumed:
 577 *   o EC header is always at offset zero - this cannot be changed;
 578 *   o VID header starts just after the EC header at the closest address
 579 *     aligned to @io->hdrs_min_io_size;
 580 *   o data starts just after the VID header at the closest address aligned to
 581 *     @io->min_io_size
 582 *
 583 * This function returns zero in case of success and a negative error code in
 584 * case of failure.
 585 */
 586static int io_init(struct ubi_device *ubi, int max_beb_per1024)
 587{
 588	dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
 589	dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
 590
 591	if (ubi->mtd->numeraseregions != 0) {
 592		/*
 593		 * Some flashes have several erase regions. Different regions
 594		 * may have different eraseblock size and other
 595		 * characteristics. It looks like mostly multi-region flashes
 596		 * have one "main" region and one or more small regions to
 597		 * store boot loader code or boot parameters or whatever. I
 598		 * guess we should just pick the largest region. But this is
 599		 * not implemented.
 600		 */
 601		ubi_err(ubi, "multiple regions, not implemented");
 602		return -EINVAL;
 603	}
 604
 605	if (ubi->vid_hdr_offset < 0)
 606		return -EINVAL;
 607
 608	/*
 609	 * Note, in this implementation we support MTD devices with 0x7FFFFFFF
 610	 * physical eraseblocks maximum.
 611	 */
 612
 613	ubi->peb_size   = ubi->mtd->erasesize;
 614	ubi->peb_count  = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
 615	ubi->flash_size = ubi->mtd->size;
 616
 617	if (mtd_can_have_bb(ubi->mtd)) {
 618		ubi->bad_allowed = 1;
 619		ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
 620	}
 621
 622	if (ubi->mtd->type == MTD_NORFLASH) {
 623		ubi_assert(ubi->mtd->writesize == 1);
 624		ubi->nor_flash = 1;
 625	}
 626
 627	ubi->min_io_size = ubi->mtd->writesize;
 628	ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
 629
 630	/*
 631	 * Make sure minimal I/O unit is power of 2. Note, there is no
 632	 * fundamental reason for this assumption. It is just an optimization
 633	 * which allows us to avoid costly division operations.
 634	 */
 635	if (!is_power_of_2(ubi->min_io_size)) {
 636		ubi_err(ubi, "min. I/O unit (%d) is not power of 2",
 637			ubi->min_io_size);
 638		return -EINVAL;
 639	}
 640
 641	ubi_assert(ubi->hdrs_min_io_size > 0);
 642	ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size);
 643	ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
 644
 645	ubi->max_write_size = ubi->mtd->writebufsize;
 646	/*
 647	 * Maximum write size has to be greater or equivalent to min. I/O
 648	 * size, and be multiple of min. I/O size.
 649	 */
 650	if (ubi->max_write_size < ubi->min_io_size ||
 651	    ubi->max_write_size % ubi->min_io_size ||
 652	    !is_power_of_2(ubi->max_write_size)) {
 653		ubi_err(ubi, "bad write buffer size %d for %d min. I/O unit",
 654			ubi->max_write_size, ubi->min_io_size);
 655		return -EINVAL;
 656	}
 657
 658	/* Calculate default aligned sizes of EC and VID headers */
 659	ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size);
 660	ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size);
 661
 662	dbg_gen("min_io_size      %d", ubi->min_io_size);
 663	dbg_gen("max_write_size   %d", ubi->max_write_size);
 664	dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
 665	dbg_gen("ec_hdr_alsize    %d", ubi->ec_hdr_alsize);
 666	dbg_gen("vid_hdr_alsize   %d", ubi->vid_hdr_alsize);
 667
 668	if (ubi->vid_hdr_offset == 0)
 669		/* Default offset */
 670		ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
 671				      ubi->ec_hdr_alsize;
 672	else {
 673		ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
 674						~(ubi->hdrs_min_io_size - 1);
 675		ubi->vid_hdr_shift = ubi->vid_hdr_offset -
 676						ubi->vid_hdr_aloffset;
 677	}
 678
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 679	/* Similar for the data offset */
 680	ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
 681	ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
 682
 683	dbg_gen("vid_hdr_offset   %d", ubi->vid_hdr_offset);
 684	dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
 685	dbg_gen("vid_hdr_shift    %d", ubi->vid_hdr_shift);
 686	dbg_gen("leb_start        %d", ubi->leb_start);
 687
 688	/* The shift must be aligned to 32-bit boundary */
 689	if (ubi->vid_hdr_shift % 4) {
 690		ubi_err(ubi, "unaligned VID header shift %d",
 691			ubi->vid_hdr_shift);
 692		return -EINVAL;
 693	}
 694
 695	/* Check sanity */
 696	if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
 697	    ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
 698	    ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
 699	    ubi->leb_start & (ubi->min_io_size - 1)) {
 700		ubi_err(ubi, "bad VID header (%d) or data offsets (%d)",
 701			ubi->vid_hdr_offset, ubi->leb_start);
 702		return -EINVAL;
 703	}
 704
 705	/*
 706	 * Set maximum amount of physical erroneous eraseblocks to be 10%.
 707	 * Erroneous PEB are those which have read errors.
 708	 */
 709	ubi->max_erroneous = ubi->peb_count / 10;
 710	if (ubi->max_erroneous < 16)
 711		ubi->max_erroneous = 16;
 712	dbg_gen("max_erroneous    %d", ubi->max_erroneous);
 713
 714	/*
 715	 * It may happen that EC and VID headers are situated in one minimal
 716	 * I/O unit. In this case we can only accept this UBI image in
 717	 * read-only mode.
 718	 */
 719	if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
 720		ubi_warn(ubi, "EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
 721		ubi->ro_mode = 1;
 722	}
 723
 724	ubi->leb_size = ubi->peb_size - ubi->leb_start;
 725
 726	if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
 727		ubi_msg(ubi, "MTD device %d is write-protected, attach in read-only mode",
 728			ubi->mtd->index);
 729		ubi->ro_mode = 1;
 730	}
 731
 732	/*
 733	 * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
 734	 * unfortunately, MTD does not provide this information. We should loop
 735	 * over all physical eraseblocks and invoke mtd->block_is_bad() for
 736	 * each physical eraseblock. So, we leave @ubi->bad_peb_count
 737	 * uninitialized so far.
 738	 */
 739
 740	return 0;
 741}
 742
 743/**
 744 * autoresize - re-size the volume which has the "auto-resize" flag set.
 745 * @ubi: UBI device description object
 746 * @vol_id: ID of the volume to re-size
 747 *
 748 * This function re-sizes the volume marked by the %UBI_VTBL_AUTORESIZE_FLG in
 749 * the volume table to the largest possible size. See comments in ubi-header.h
 750 * for more description of the flag. Returns zero in case of success and a
 751 * negative error code in case of failure.
 752 */
 753static int autoresize(struct ubi_device *ubi, int vol_id)
 754{
 755	struct ubi_volume_desc desc;
 756	struct ubi_volume *vol = ubi->volumes[vol_id];
 757	int err, old_reserved_pebs = vol->reserved_pebs;
 758
 759	if (ubi->ro_mode) {
 760		ubi_warn(ubi, "skip auto-resize because of R/O mode");
 761		return 0;
 762	}
 763
 764	/*
 765	 * Clear the auto-resize flag in the volume in-memory copy of the
 766	 * volume table, and 'ubi_resize_volume()' will propagate this change
 767	 * to the flash.
 768	 */
 769	ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
 770
 771	if (ubi->avail_pebs == 0) {
 772		struct ubi_vtbl_record vtbl_rec;
 773
 774		/*
 775		 * No available PEBs to re-size the volume, clear the flag on
 776		 * flash and exit.
 777		 */
 778		vtbl_rec = ubi->vtbl[vol_id];
 779		err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
 780		if (err)
 781			ubi_err(ubi, "cannot clean auto-resize flag for volume %d",
 782				vol_id);
 783	} else {
 784		desc.vol = vol;
 785		err = ubi_resize_volume(&desc,
 786					old_reserved_pebs + ubi->avail_pebs);
 787		if (err)
 788			ubi_err(ubi, "cannot auto-resize volume %d",
 789				vol_id);
 790	}
 791
 792	if (err)
 793		return err;
 794
 795	ubi_msg(ubi, "volume %d (\"%s\") re-sized from %d to %d LEBs",
 796		vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs);
 797	return 0;
 798}
 799
 800/**
 801 * ubi_attach_mtd_dev - attach an MTD device.
 802 * @mtd: MTD device description object
 803 * @ubi_num: number to assign to the new UBI device
 804 * @vid_hdr_offset: VID header offset
 805 * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
 
 
 806 *
 807 * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
 808 * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
 809 * which case this function finds a vacant device number and assigns it
 810 * automatically. Returns the new UBI device number in case of success and a
 811 * negative error code in case of failure.
 812 *
 
 
 
 
 813 * Note, the invocations of this function has to be serialized by the
 814 * @ubi_devices_mutex.
 815 */
 816int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 817		       int vid_hdr_offset, int max_beb_per1024)
 
 818{
 819	struct ubi_device *ubi;
 820	int i, err;
 821
 822	if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
 823		return -EINVAL;
 824
 825	if (!max_beb_per1024)
 826		max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
 827
 828	/*
 829	 * Check if we already have the same MTD device attached.
 830	 *
 831	 * Note, this function assumes that UBI devices creations and deletions
 832	 * are serialized, so it does not take the &ubi_devices_lock.
 833	 */
 834	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 835		ubi = ubi_devices[i];
 836		if (ubi && mtd->index == ubi->mtd->index) {
 837			pr_err("ubi: mtd%d is already attached to ubi%d\n",
 838				mtd->index, i);
 839			return -EEXIST;
 840		}
 841	}
 842
 843	/*
 844	 * Make sure this MTD device is not emulated on top of an UBI volume
 845	 * already. Well, generally this recursion works fine, but there are
 846	 * different problems like the UBI module takes a reference to itself
 847	 * by attaching (and thus, opening) the emulated MTD device. This
 848	 * results in inability to unload the module. And in general it makes
 849	 * no sense to attach emulated MTD devices, so we prohibit this.
 850	 */
 851	if (mtd->type == MTD_UBIVOLUME) {
 852		pr_err("ubi: refuse attaching mtd%d - it is already emulated on top of UBI\n",
 853			mtd->index);
 854		return -EINVAL;
 855	}
 856
 857	/*
 858	 * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes.
 859	 * MLC NAND is different and needs special care, otherwise UBI or UBIFS
 860	 * will die soon and you will lose all your data.
 
 
 861	 */
 862	if (mtd->type == MTD_MLCNANDFLASH) {
 
 863		pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n",
 864			mtd->index);
 865		return -EINVAL;
 866	}
 867
 
 
 
 
 
 
 
 868	if (ubi_num == UBI_DEV_NUM_AUTO) {
 869		/* Search for an empty slot in the @ubi_devices array */
 870		for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
 871			if (!ubi_devices[ubi_num])
 872				break;
 873		if (ubi_num == UBI_MAX_DEVICES) {
 874			pr_err("ubi: only %d UBI devices may be created\n",
 875				UBI_MAX_DEVICES);
 876			return -ENFILE;
 877		}
 878	} else {
 879		if (ubi_num >= UBI_MAX_DEVICES)
 880			return -EINVAL;
 881
 882		/* Make sure ubi_num is not busy */
 883		if (ubi_devices[ubi_num]) {
 884			pr_err("ubi: ubi%i already exists\n", ubi_num);
 885			return -EEXIST;
 886		}
 887	}
 888
 889	ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
 890	if (!ubi)
 891		return -ENOMEM;
 892
 893	device_initialize(&ubi->dev);
 894	ubi->dev.release = dev_release;
 895	ubi->dev.class = &ubi_class;
 896	ubi->dev.groups = ubi_dev_groups;
 
 897
 898	ubi->mtd = mtd;
 899	ubi->ubi_num = ubi_num;
 900	ubi->vid_hdr_offset = vid_hdr_offset;
 901	ubi->autoresize_vol_id = -1;
 902
 903#ifdef CONFIG_MTD_UBI_FASTMAP
 904	ubi->fm_pool.used = ubi->fm_pool.size = 0;
 905	ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
 906
 907	/*
 908	 * fm_pool.max_size is 5% of the total number of PEBs but it's also
 909	 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
 910	 */
 911	ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
 912		ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
 913	ubi->fm_pool.max_size = max(ubi->fm_pool.max_size,
 914		UBI_FM_MIN_POOL_SIZE);
 915
 916	ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
 917	ubi->fm_disabled = !fm_autoconvert;
 
 918	if (fm_debug)
 919		ubi_enable_dbg_chk_fastmap(ubi);
 920
 921	if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
 922	    <= UBI_FM_MAX_START) {
 923		ubi_err(ubi, "More than %i PEBs are needed for fastmap, sorry.",
 924			UBI_FM_MAX_START);
 925		ubi->fm_disabled = 1;
 926	}
 927
 928	ubi_msg(ubi, "default fastmap pool size: %d", ubi->fm_pool.max_size);
 929	ubi_msg(ubi, "default fastmap WL pool size: %d",
 930		ubi->fm_wl_pool.max_size);
 931#else
 932	ubi->fm_disabled = 1;
 933#endif
 934	mutex_init(&ubi->buf_mutex);
 935	mutex_init(&ubi->ckvol_mutex);
 936	mutex_init(&ubi->device_mutex);
 937	spin_lock_init(&ubi->volumes_lock);
 938	init_rwsem(&ubi->fm_protect);
 939	init_rwsem(&ubi->fm_eba_sem);
 940
 941	ubi_msg(ubi, "attaching mtd%d", mtd->index);
 942
 943	err = io_init(ubi, max_beb_per1024);
 944	if (err)
 945		goto out_free;
 946
 947	err = -ENOMEM;
 948	ubi->peb_buf = vmalloc(ubi->peb_size);
 949	if (!ubi->peb_buf)
 950		goto out_free;
 951
 952#ifdef CONFIG_MTD_UBI_FASTMAP
 953	ubi->fm_size = ubi_calc_fm_size(ubi);
 954	ubi->fm_buf = vzalloc(ubi->fm_size);
 955	if (!ubi->fm_buf)
 956		goto out_free;
 957#endif
 958	err = ubi_attach(ubi, 0);
 959	if (err) {
 960		ubi_err(ubi, "failed to attach mtd%d, error %d",
 961			mtd->index, err);
 962		goto out_free;
 963	}
 964
 965	if (ubi->autoresize_vol_id != -1) {
 966		err = autoresize(ubi, ubi->autoresize_vol_id);
 967		if (err)
 968			goto out_detach;
 969	}
 970
 971	/* Make device "available" before it becomes accessible via sysfs */
 972	ubi_devices[ubi_num] = ubi;
 973
 974	err = uif_init(ubi);
 975	if (err)
 976		goto out_detach;
 977
 978	err = ubi_debugfs_init_dev(ubi);
 979	if (err)
 980		goto out_uif;
 981
 982	ubi->bgt_thread = kthread_create(ubi_thread, ubi, "%s", ubi->bgt_name);
 983	if (IS_ERR(ubi->bgt_thread)) {
 984		err = PTR_ERR(ubi->bgt_thread);
 985		ubi_err(ubi, "cannot spawn \"%s\", error %d",
 986			ubi->bgt_name, err);
 987		goto out_debugfs;
 988	}
 989
 990	ubi_msg(ubi, "attached mtd%d (name \"%s\", size %llu MiB)",
 991		mtd->index, mtd->name, ubi->flash_size >> 20);
 992	ubi_msg(ubi, "PEB size: %d bytes (%d KiB), LEB size: %d bytes",
 993		ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
 994	ubi_msg(ubi, "min./max. I/O unit sizes: %d/%d, sub-page size %d",
 995		ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
 996	ubi_msg(ubi, "VID header offset: %d (aligned %d), data offset: %d",
 997		ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
 998	ubi_msg(ubi, "good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
 999		ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1000	ubi_msg(ubi, "user volume: %d, internal volumes: %d, max. volumes count: %d",
1001		ubi->vol_count - UBI_INT_VOL_COUNT, UBI_INT_VOL_COUNT,
1002		ubi->vtbl_slots);
1003	ubi_msg(ubi, "max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1004		ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1005		ubi->image_seq);
1006	ubi_msg(ubi, "available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1007		ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1008
1009	/*
1010	 * The below lock makes sure we do not race with 'ubi_thread()' which
1011	 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1012	 */
1013	spin_lock(&ubi->wl_lock);
1014	ubi->thread_enabled = 1;
1015	wake_up_process(ubi->bgt_thread);
1016	spin_unlock(&ubi->wl_lock);
1017
 
1018	ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
1019	return ubi_num;
1020
1021out_debugfs:
1022	ubi_debugfs_exit_dev(ubi);
1023out_uif:
1024	uif_close(ubi);
1025out_detach:
1026	ubi_devices[ubi_num] = NULL;
1027	ubi_wl_close(ubi);
1028	ubi_free_internal_volumes(ubi);
1029	vfree(ubi->vtbl);
1030out_free:
1031	vfree(ubi->peb_buf);
1032	vfree(ubi->fm_buf);
1033	put_device(&ubi->dev);
1034	return err;
1035}
1036
1037/**
1038 * ubi_detach_mtd_dev - detach an MTD device.
1039 * @ubi_num: UBI device number to detach from
1040 * @anyway: detach MTD even if device reference count is not zero
1041 *
1042 * This function destroys an UBI device number @ubi_num and detaches the
1043 * underlying MTD device. Returns zero in case of success and %-EBUSY if the
1044 * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not
1045 * exist.
1046 *
1047 * Note, the invocations of this function has to be serialized by the
1048 * @ubi_devices_mutex.
1049 */
1050int ubi_detach_mtd_dev(int ubi_num, int anyway)
1051{
1052	struct ubi_device *ubi;
1053
1054	if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1055		return -EINVAL;
1056
1057	ubi = ubi_get_device(ubi_num);
1058	if (!ubi)
1059		return -EINVAL;
1060
1061	spin_lock(&ubi_devices_lock);
1062	put_device(&ubi->dev);
1063	ubi->ref_count -= 1;
1064	if (ubi->ref_count) {
1065		if (!anyway) {
1066			spin_unlock(&ubi_devices_lock);
1067			return -EBUSY;
1068		}
1069		/* This may only happen if there is a bug */
1070		ubi_err(ubi, "%s reference count %d, destroy anyway",
1071			ubi->ubi_name, ubi->ref_count);
1072	}
1073	ubi_devices[ubi_num] = NULL;
1074	spin_unlock(&ubi_devices_lock);
1075
1076	ubi_assert(ubi_num == ubi->ubi_num);
1077	ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
1078	ubi_msg(ubi, "detaching mtd%d", ubi->mtd->index);
1079#ifdef CONFIG_MTD_UBI_FASTMAP
1080	/* If we don't write a new fastmap at detach time we lose all
1081	 * EC updates that have been made since the last written fastmap.
1082	 * In case of fastmap debugging we omit the update to simulate an
1083	 * unclean shutdown. */
1084	if (!ubi_dbg_chk_fastmap(ubi))
1085		ubi_update_fastmap(ubi);
1086#endif
1087	/*
1088	 * Before freeing anything, we have to stop the background thread to
1089	 * prevent it from doing anything on this device while we are freeing.
1090	 */
1091	if (ubi->bgt_thread)
1092		kthread_stop(ubi->bgt_thread);
1093
 
 
 
1094	ubi_debugfs_exit_dev(ubi);
1095	uif_close(ubi);
1096
1097	ubi_wl_close(ubi);
1098	ubi_free_internal_volumes(ubi);
1099	vfree(ubi->vtbl);
1100	put_mtd_device(ubi->mtd);
1101	vfree(ubi->peb_buf);
1102	vfree(ubi->fm_buf);
1103	ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
 
1104	put_device(&ubi->dev);
1105	return 0;
1106}
1107
1108/**
1109 * open_mtd_by_chdev - open an MTD device by its character device node path.
1110 * @mtd_dev: MTD character device node path
1111 *
1112 * This helper function opens an MTD device by its character node device path.
1113 * Returns MTD device description object in case of success and a negative
1114 * error code in case of failure.
1115 */
1116static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1117{
1118	int err, minor;
1119	struct path path;
1120	struct kstat stat;
1121
1122	/* Probably this is an MTD character device node path */
1123	err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1124	if (err)
1125		return ERR_PTR(err);
1126
1127	err = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);
1128	path_put(&path);
1129	if (err)
1130		return ERR_PTR(err);
1131
1132	/* MTD device number is defined by the major / minor numbers */
1133	if (MAJOR(stat.rdev) != MTD_CHAR_MAJOR || !S_ISCHR(stat.mode))
1134		return ERR_PTR(-EINVAL);
1135
1136	minor = MINOR(stat.rdev);
1137
1138	if (minor & 1)
1139		/*
1140		 * Just do not think the "/dev/mtdrX" devices support is need,
1141		 * so do not support them to avoid doing extra work.
1142		 */
1143		return ERR_PTR(-EINVAL);
1144
1145	return get_mtd_device(NULL, minor / 2);
1146}
1147
1148/**
1149 * open_mtd_device - open MTD device by name, character device path, or number.
1150 * @mtd_dev: name, character device node path, or MTD device device number
1151 *
1152 * This function tries to open and MTD device described by @mtd_dev string,
1153 * which is first treated as ASCII MTD device number, and if it is not true, it
1154 * is treated as MTD device name, and if that is also not true, it is treated
1155 * as MTD character device node path. Returns MTD device description object in
1156 * case of success and a negative error code in case of failure.
1157 */
1158static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1159{
1160	struct mtd_info *mtd;
1161	int mtd_num;
1162	char *endp;
1163
1164	mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1165	if (*endp != '\0' || mtd_dev == endp) {
1166		/*
1167		 * This does not look like an ASCII integer, probably this is
1168		 * MTD device name.
1169		 */
1170		mtd = get_mtd_device_nm(mtd_dev);
1171		if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1172			/* Probably this is an MTD character device node path */
1173			mtd = open_mtd_by_chdev(mtd_dev);
1174	} else
1175		mtd = get_mtd_device(NULL, mtd_num);
1176
1177	return mtd;
1178}
1179
1180static int __init ubi_init(void)
1181{
1182	int err, i, k;
1183
1184	/* Ensure that EC and VID headers have correct size */
1185	BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1186	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1187
1188	if (mtd_devs > UBI_MAX_DEVICES) {
1189		pr_err("UBI error: too many MTD devices, maximum is %d\n",
1190		       UBI_MAX_DEVICES);
1191		return -EINVAL;
1192	}
1193
1194	/* Create base sysfs directory and sysfs files */
1195	err = class_register(&ubi_class);
1196	if (err < 0)
1197		return err;
1198
1199	err = misc_register(&ubi_ctrl_cdev);
1200	if (err) {
1201		pr_err("UBI error: cannot register device\n");
1202		goto out;
1203	}
1204
1205	ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1206					      sizeof(struct ubi_wl_entry),
1207					      0, 0, NULL);
1208	if (!ubi_wl_entry_slab) {
1209		err = -ENOMEM;
1210		goto out_dev_unreg;
1211	}
1212
1213	err = ubi_debugfs_init();
1214	if (err)
1215		goto out_slab;
1216
1217
1218	/* Attach MTD devices */
1219	for (i = 0; i < mtd_devs; i++) {
1220		struct mtd_dev_param *p = &mtd_dev_param[i];
1221		struct mtd_info *mtd;
1222
1223		cond_resched();
1224
1225		mtd = open_mtd_device(p->name);
1226		if (IS_ERR(mtd)) {
1227			err = PTR_ERR(mtd);
1228			pr_err("UBI error: cannot open mtd %s, error %d\n",
1229			       p->name, err);
1230			/* See comment below re-ubi_is_module(). */
1231			if (ubi_is_module())
1232				goto out_detach;
1233			continue;
1234		}
1235
1236		mutex_lock(&ubi_devices_mutex);
1237		err = ubi_attach_mtd_dev(mtd, p->ubi_num,
1238					 p->vid_hdr_offs, p->max_beb_per1024);
 
 
1239		mutex_unlock(&ubi_devices_mutex);
1240		if (err < 0) {
1241			pr_err("UBI error: cannot attach mtd%d\n",
1242			       mtd->index);
1243			put_mtd_device(mtd);
1244
1245			/*
1246			 * Originally UBI stopped initializing on any error.
1247			 * However, later on it was found out that this
1248			 * behavior is not very good when UBI is compiled into
1249			 * the kernel and the MTD devices to attach are passed
1250			 * through the command line. Indeed, UBI failure
1251			 * stopped whole boot sequence.
1252			 *
1253			 * To fix this, we changed the behavior for the
1254			 * non-module case, but preserved the old behavior for
1255			 * the module case, just for compatibility. This is a
1256			 * little inconsistent, though.
1257			 */
1258			if (ubi_is_module())
1259				goto out_detach;
1260		}
1261	}
1262
1263	err = ubiblock_init();
1264	if (err) {
1265		pr_err("UBI error: block: cannot initialize, error %d\n", err);
1266
1267		/* See comment above re-ubi_is_module(). */
1268		if (ubi_is_module())
1269			goto out_detach;
1270	}
1271
1272	return 0;
1273
1274out_detach:
1275	for (k = 0; k < i; k++)
1276		if (ubi_devices[k]) {
1277			mutex_lock(&ubi_devices_mutex);
1278			ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1279			mutex_unlock(&ubi_devices_mutex);
1280		}
1281	ubi_debugfs_exit();
1282out_slab:
1283	kmem_cache_destroy(ubi_wl_entry_slab);
1284out_dev_unreg:
1285	misc_deregister(&ubi_ctrl_cdev);
1286out:
1287	class_unregister(&ubi_class);
1288	pr_err("UBI error: cannot initialize UBI, error %d\n", err);
1289	return err;
1290}
1291late_initcall(ubi_init);
1292
1293static void __exit ubi_exit(void)
1294{
1295	int i;
1296
1297	ubiblock_exit();
1298
1299	for (i = 0; i < UBI_MAX_DEVICES; i++)
1300		if (ubi_devices[i]) {
1301			mutex_lock(&ubi_devices_mutex);
1302			ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1303			mutex_unlock(&ubi_devices_mutex);
1304		}
1305	ubi_debugfs_exit();
1306	kmem_cache_destroy(ubi_wl_entry_slab);
1307	misc_deregister(&ubi_ctrl_cdev);
1308	class_unregister(&ubi_class);
1309}
1310module_exit(ubi_exit);
1311
1312/**
1313 * bytes_str_to_int - convert a number of bytes string into an integer.
1314 * @str: the string to convert
1315 *
1316 * This function returns positive resulting integer in case of success and a
1317 * negative error code in case of failure.
1318 */
1319static int bytes_str_to_int(const char *str)
1320{
1321	char *endp;
1322	unsigned long result;
1323
1324	result = simple_strtoul(str, &endp, 0);
1325	if (str == endp || result >= INT_MAX) {
1326		pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1327		return -EINVAL;
1328	}
1329
1330	switch (*endp) {
1331	case 'G':
1332		result *= 1024;
 
1333	case 'M':
1334		result *= 1024;
 
1335	case 'K':
1336		result *= 1024;
1337		if (endp[1] == 'i' && endp[2] == 'B')
1338			endp += 2;
1339	case '\0':
1340		break;
1341	default:
1342		pr_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1343		return -EINVAL;
1344	}
1345
1346	return result;
1347}
1348
1349/**
1350 * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter.
1351 * @val: the parameter value to parse
1352 * @kp: not used
1353 *
1354 * This function returns zero in case of success and a negative error code in
1355 * case of error.
1356 */
1357static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
1358{
1359	int i, len;
1360	struct mtd_dev_param *p;
1361	char buf[MTD_PARAM_LEN_MAX];
1362	char *pbuf = &buf[0];
1363	char *tokens[MTD_PARAM_MAX_COUNT], *token;
1364
1365	if (!val)
1366		return -EINVAL;
1367
1368	if (mtd_devs == UBI_MAX_DEVICES) {
1369		pr_err("UBI error: too many parameters, max. is %d\n",
1370		       UBI_MAX_DEVICES);
1371		return -EINVAL;
1372	}
1373
1374	len = strnlen(val, MTD_PARAM_LEN_MAX);
1375	if (len == MTD_PARAM_LEN_MAX) {
1376		pr_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1377		       val, MTD_PARAM_LEN_MAX);
1378		return -EINVAL;
1379	}
1380
1381	if (len == 0) {
1382		pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1383		return 0;
1384	}
1385
1386	strcpy(buf, val);
1387
1388	/* Get rid of the final newline */
1389	if (buf[len - 1] == '\n')
1390		buf[len - 1] = '\0';
1391
1392	for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1393		tokens[i] = strsep(&pbuf, ",");
1394
1395	if (pbuf) {
1396		pr_err("UBI error: too many arguments at \"%s\"\n", val);
1397		return -EINVAL;
1398	}
1399
1400	p = &mtd_dev_param[mtd_devs];
1401	strcpy(&p->name[0], tokens[0]);
1402
1403	token = tokens[1];
1404	if (token) {
1405		p->vid_hdr_offs = bytes_str_to_int(token);
1406
1407		if (p->vid_hdr_offs < 0)
1408			return p->vid_hdr_offs;
1409	}
1410
1411	token = tokens[2];
1412	if (token) {
1413		int err = kstrtoint(token, 10, &p->max_beb_per1024);
1414
1415		if (err) {
1416			pr_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1417			       token);
1418			return -EINVAL;
1419		}
1420	}
1421
1422	token = tokens[3];
1423	if (token) {
1424		int err = kstrtoint(token, 10, &p->ubi_num);
1425
1426		if (err) {
1427			pr_err("UBI error: bad value for ubi_num parameter: %s",
1428			       token);
1429			return -EINVAL;
1430		}
1431	} else
1432		p->ubi_num = UBI_DEV_NUM_AUTO;
1433
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1434	mtd_devs += 1;
1435	return 0;
1436}
1437
1438module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 0400);
1439MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024[,ubi_num]]].\n"
1440		      "Multiple \"mtd\" parameters may be specified.\n"
1441		      "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1442		      "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1443		      "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1444		      __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1445		      "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
 
 
1446		      "\n"
1447		      "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1448		      "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"
1449		      "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"
1450		      "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"
 
1451		      "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1452#ifdef CONFIG_MTD_UBI_FASTMAP
1453module_param(fm_autoconvert, bool, 0644);
1454MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1455module_param(fm_debug, bool, 0);
1456MODULE_PARM_DESC(fm_debug, "Set this parameter to enable fastmap debugging by default. Warning, this will make fastmap slow!");
1457#endif
1458MODULE_VERSION(__stringify(UBI_VERSION));
1459MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1460MODULE_AUTHOR("Artem Bityutskiy");
1461MODULE_LICENSE("GPL");