/* * Copyright (c) International Business Machines Corp., 2006 * Copyright (c) Nokia Corporation, 2007 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See * the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Author: Artem Bityutskiy (Битюцкий Артём), * Frank Haverkamp */ /* * This file includes UBI initialization and building of UBI devices. * * When UBI is initialized, it attaches all the MTD devices specified as the * module load parameters or the kernel boot parameters. If MTD devices were * specified, UBI does not attach any MTD device, but it is possible to do * later using the "UBI control device". * * At the moment we only attach UBI devices by scanning, which will become a * bottleneck when flashes reach certain large size. Then one may improve UBI * and add other methods, although it does not seem to be easy to do. */ #include #include #include #include #include #include #include #include #include #include #include #include "ubi.h" /* Maximum length of the 'mtd=' parameter */ #define MTD_PARAM_LEN_MAX 64 #ifdef CONFIG_MTD_UBI_MODULE #define ubi_is_module() 1 #else #define ubi_is_module() 0 #endif /** * struct mtd_dev_param - MTD device parameter description data structure. * @name: MTD character device node path, MTD device name, or MTD device number * string * @vid_hdr_offs: VID header offset */ struct mtd_dev_param { char name[MTD_PARAM_LEN_MAX]; int vid_hdr_offs; }; /* Numbers of elements set in the @mtd_dev_param array */ static int __initdata mtd_devs; /* MTD devices specification parameters */ static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES]; /* Root UBI "class" object (corresponds to '//class/ubi/') */ struct class *ubi_class; /* Slab cache for wear-leveling entries */ struct kmem_cache *ubi_wl_entry_slab; /* UBI control character device */ static struct miscdevice ubi_ctrl_cdev = { .minor = MISC_DYNAMIC_MINOR, .name = "ubi_ctrl", .fops = &ubi_ctrl_cdev_operations, }; /* All UBI devices in system */ static struct ubi_device *ubi_devices[UBI_MAX_DEVICES]; /* Serializes UBI devices creations and removals */ DEFINE_MUTEX(ubi_devices_mutex); /* Protects @ubi_devices and @ubi->ref_count */ static DEFINE_SPINLOCK(ubi_devices_lock); /* "Show" method for files in '//class/ubi/' */ static ssize_t ubi_version_show(struct class *class, struct class_attribute *attr, char *buf) { return sprintf(buf, "%d\n", UBI_VERSION); } /* UBI version attribute ('//class/ubi/version') */ static struct class_attribute ubi_version = __ATTR(version, S_IRUGO, ubi_version_show, NULL); static ssize_t dev_attribute_show(struct device *dev, struct device_attribute *attr, char *buf); /* UBI device attributes (correspond to files in '//class/ubi/ubiX') */ static struct device_attribute dev_eraseblock_size = __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_avail_eraseblocks = __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_total_eraseblocks = __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_volumes_count = __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_max_ec = __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_reserved_for_bad = __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_bad_peb_count = __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_max_vol_count = __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_min_io_size = __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_bgt_enabled = __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL); static struct device_attribute dev_mtd_num = __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL); /** * ubi_volume_notify - send a volume change notification. * @ubi: UBI device description object * @vol: volume description object of the changed volume * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) * * This is a helper function which notifies all subscribers about a volume * change event (creation, removal, re-sizing, re-naming, updating). Returns * zero in case of success and a negative error code in case of failure. */ int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype) { struct ubi_notification nt; ubi_do_get_device_info(ubi, &nt.di); ubi_do_get_volume_info(ubi, vol, &nt.vi); return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt); } /** * ubi_notify_all - send a notification to all volumes. * @ubi: UBI device description object * @ntype: notification type to send (%UBI_VOLUME_ADDED, etc) * @nb: the notifier to call * * This function walks all volumes of UBI device @ubi and sends the @ntype * notification for each volume. If @nb is %NULL, then all registered notifiers * are called, otherwise only the @nb notifier is called. Returns the number of * sent notifications. */ int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb) { struct ubi_notification nt; int i, count = 0; ubi_do_get_device_info(ubi, &nt.di); mutex_lock(&ubi->device_mutex); for (i = 0; i < ubi->vtbl_slots; i++) { /* * Since the @ubi->device is locked, and we are not going to * change @ubi->volumes, we do not have to lock * @ubi->volumes_lock. */ if (!ubi->volumes[i]) continue; ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi); if (nb) nb->notifier_call(nb, ntype, &nt); else blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt); count += 1; } mutex_unlock(&ubi->device_mutex); return count; } /** * ubi_enumerate_volumes - send "add" notification for all existing volumes. * @nb: the notifier to call * * This function walks all UBI devices and volumes and sends the * %UBI_VOLUME_ADDED notification for each volume. If @nb is %NULL, then all * registered notifiers are called, otherwise only the @nb notifier is called. * Returns the number of sent notifications. */ int ubi_enumerate_volumes(struct notifier_block *nb) { int i, count = 0; /* * Since the @ubi_devices_mutex is locked, and we are not going to * change @ubi_devices, we do not have to lock @ubi_devices_lock. */ for (i = 0; i < UBI_MAX_DEVICES; i++) { struct ubi_device *ubi = ubi_devices[i]; if (!ubi) continue; count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb); } return count; } /** * ubi_get_device - get UBI device. * @ubi_num: UBI device number * * This function returns UBI device description object for UBI device number * @ubi_num, or %NULL if the device does not exist. This function increases the * device reference count to prevent removal of the device. In other words, the * device cannot be removed if its reference count is not zero. */ struct ubi_device *ubi_get_device(int ubi_num) { struct ubi_device *ubi; spin_lock(&ubi_devices_lock); ubi = ubi_devices[ubi_num]; if (ubi) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; get_device(&ubi->dev); } spin_unlock(&ubi_devices_lock); return ubi; } /** * ubi_put_device - drop an UBI device reference. * @ubi: UBI device description object */ void ubi_put_device(struct ubi_device *ubi) { spin_lock(&ubi_devices_lock); ubi->ref_count -= 1; put_device(&ubi->dev); spin_unlock(&ubi_devices_lock); } /** * ubi_get_by_major - get UBI device by character device major number. * @major: major number * * This function is similar to 'ubi_get_device()', but it searches the device * by its major number. */ struct ubi_device *ubi_get_by_major(int major) { int i; struct ubi_device *ubi; spin_lock(&ubi_devices_lock); for (i = 0; i < UBI_MAX_DEVICES; i++) { ubi = ubi_devices[i]; if (ubi && MAJOR(ubi->cdev.dev) == major) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; get_device(&ubi->dev); spin_unlock(&ubi_devices_lock); return ubi; } } spin_unlock(&ubi_devices_lock); return NULL; } /** * ubi_major2num - get UBI device number by character device major number. * @major: major number * * This function searches UBI device number object by its major number. If UBI * device was not found, this function returns -ENODEV, otherwise the UBI device * number is returned. */ int ubi_major2num(int major) { int i, ubi_num = -ENODEV; spin_lock(&ubi_devices_lock); for (i = 0; i < UBI_MAX_DEVICES; i++) { struct ubi_device *ubi = ubi_devices[i]; if (ubi && MAJOR(ubi->cdev.dev) == major) { ubi_num = ubi->ubi_num; break; } } spin_unlock(&ubi_devices_lock); return ubi_num; } /* "Show" method for files in '//class/ubi/ubiX/' */ static ssize_t dev_attribute_show(struct device *dev, struct device_attribute *attr, char *buf) { ssize_t ret; struct ubi_device *ubi; /* * The below code looks weird, but it actually makes sense. We get the * UBI device reference from the contained 'struct ubi_device'. But it * is unclear if the device was removed or not yet. Indeed, if the * device was removed before we increased its reference count, * 'ubi_get_device()' will return -ENODEV and we fail. * * Remember, 'struct ubi_device' is freed in the release function, so * we still can use 'ubi->ubi_num'. */ ubi = container_of(dev, struct ubi_device, dev); ubi = ubi_get_device(ubi->ubi_num); if (!ubi) return -ENODEV; if (attr == &dev_eraseblock_size) ret = sprintf(buf, "%d\n", ubi->leb_size); else if (attr == &dev_avail_eraseblocks) ret = sprintf(buf, "%d\n", ubi->avail_pebs); else if (attr == &dev_total_eraseblocks) ret = sprintf(buf, "%d\n", ubi->good_peb_count); else if (attr == &dev_volumes_count) ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT); else if (attr == &dev_max_ec) ret = sprintf(buf, "%d\n", ubi->max_ec); else if (attr == &dev_reserved_for_bad) ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs); else if (attr == &dev_bad_peb_count) ret = sprintf(buf, "%d\n", ubi->bad_peb_count); else if (attr == &dev_max_vol_count) ret = sprintf(buf, "%d\n", ubi->vtbl_slots); else if (attr == &dev_min_io_size) ret = sprintf(buf, "%d\n", ubi->min_io_size); else if (attr == &dev_bgt_enabled) ret = sprintf(buf, "%d\n", ubi->thread_enabled); else if (attr == &dev_mtd_num) ret = sprintf(buf, "%d\n", ubi->mtd->index); else ret = -EINVAL; ubi_put_device(ubi); return ret; } static void dev_release(struct device *dev) { struct ubi_device *ubi = container_of(dev, struct ubi_device, dev); kfree(ubi); } /** * ubi_sysfs_init - initialize sysfs for an UBI device. * @ubi: UBI device description object * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was * taken * * This function returns zero in case of success and a negative error code in * case of failure. */ static int ubi_sysfs_init(struct ubi_device *ubi, int *ref) { int err; ubi->dev.release = dev_release; ubi->dev.devt = ubi->cdev.dev; ubi->dev.class = ubi_class; dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num); err = device_register(&ubi->dev); if (err) return err; *ref = 1; err = device_create_file(&ubi->dev, &dev_eraseblock_size); if (err) return err; err = device_create_file(&ubi->dev, &dev_avail_eraseblocks); if (err) return err; err = device_create_file(&ubi->dev, &dev_total_eraseblocks); if (err) return err; err = device_create_file(&ubi->dev, &dev_volumes_count); if (err) return err; err = device_create_file(&ubi->dev, &dev_max_ec); if (err) return err; err = device_create_file(&ubi->dev, &dev_reserved_for_bad); if (err) return err; err = device_create_file(&ubi->dev, &dev_bad_peb_count); if (err) return err; err = device_create_file(&ubi->dev, &dev_max_vol_count); if (err) return err; err = device_create_file(&ubi->dev, &dev_min_io_size); if (err) return err; err = device_create_file(&ubi->dev, &dev_bgt_enabled); if (err) return err; err = device_create_file(&ubi->dev, &dev_mtd_num); return err; } /** * ubi_sysfs_close - close sysfs for an UBI device. * @ubi: UBI device description object */ static void ubi_sysfs_close(struct ubi_device *ubi) { device_remove_file(&ubi->dev, &dev_mtd_num); device_remove_file(&ubi->dev, &dev_bgt_enabled); device_remove_file(&ubi->dev, &dev_min_io_size); device_remove_file(&ubi->dev, &dev_max_vol_count); device_remove_file(&ubi->dev, &dev_bad_peb_count); device_remove_file(&ubi->dev, &dev_reserved_for_bad); device_remove_file(&ubi->dev, &dev_max_ec); device_remove_file(&ubi->dev, &dev_volumes_count); device_remove_file(&ubi->dev, &dev_total_eraseblocks); device_remove_file(&ubi->dev, &dev_avail_eraseblocks); device_remove_file(&ubi->dev, &dev_eraseblock_size); device_unregister(&ubi->dev); } /** * kill_volumes - destroy all user volumes. * @ubi: UBI device description object */ static void kill_volumes(struct ubi_device *ubi) { int i; for (i = 0; i < ubi->vtbl_slots; i++) if (ubi->volumes[i]) ubi_free_volume(ubi, ubi->volumes[i]); } /** * uif_init - initialize user interfaces for an UBI device. * @ubi: UBI device description object * @ref: set to %1 on exit in case of failure if a reference to @ubi->dev was * taken, otherwise set to %0 * * This function initializes various user interfaces for an UBI device. If the * initialization fails at an early stage, this function frees all the * resources it allocated, returns an error, and @ref is set to %0. However, * if the initialization fails after the UBI device was registered in the * driver core subsystem, this function takes a reference to @ubi->dev, because * otherwise the release function ('dev_release()') would free whole @ubi * object. The @ref argument is set to %1 in this case. The caller has to put * this reference. * * This function returns zero in case of success and a negative error code in * case of failure. */ static int uif_init(struct ubi_device *ubi, int *ref) { int i, err; dev_t dev; *ref = 0; sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num); /* * Major numbers for the UBI character devices are allocated * dynamically. Major numbers of volume character devices are * equivalent to ones of the corresponding UBI character device. Minor * numbers of UBI character devices are 0, while minor numbers of * volume character devices start from 1. Thus, we allocate one major * number and ubi->vtbl_slots + 1 minor numbers. */ err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name); if (err) { ubi_err("cannot register UBI character devices"); return err; } ubi_assert(MINOR(dev) == 0); cdev_init(&ubi->cdev, &ubi_cdev_operations); dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev)); ubi->cdev.owner = THIS_MODULE; err = cdev_add(&ubi->cdev, dev, 1); if (err) { ubi_err("cannot add character device"); goto out_unreg; } err = ubi_sysfs_init(ubi, ref); if (err) goto out_sysfs; for (i = 0; i < ubi->vtbl_slots; i++) if (ubi->volumes[i]) { err = ubi_add_volume(ubi, ubi->volumes[i]); if (err) { ubi_err("cannot add volume %d", i); goto out_volumes; } } return 0; out_volumes: kill_volumes(ubi); out_sysfs: if (*ref) get_device(&ubi->dev); ubi_sysfs_close(ubi); cdev_del(&ubi->cdev); out_unreg: unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err); return err; } /** * uif_close - close user interfaces for an UBI device. * @ubi: UBI device description object * * Note, since this function un-registers UBI volume device objects (@vol->dev), * the memory allocated voe the volumes is freed as well (in the release * function). */ static void uif_close(struct ubi_device *ubi) { kill_volumes(ubi); ubi_sysfs_close(ubi); cdev_del(&ubi->cdev); unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1); } /** * free_internal_volumes - free internal volumes. * @ubi: UBI device description object */ static void free_internal_volumes(struct ubi_device *ubi) { int i; for (i = ubi->vtbl_slots; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { kfree(ubi->volumes[i]->eba_tbl); kfree(ubi->volumes[i]); } } /** * attach_by_scanning - attach an MTD device using scanning method. * @ubi: UBI device descriptor * * This function returns zero in case of success and a negative error code in * case of failure. * * Note, currently this is the only method to attach UBI devices. Hopefully in * the future we'll have more scalable attaching methods and avoid full media * scanning. But even in this case scanning will be needed as a fall-back * attaching method if there are some on-flash table corruptions. */ static int attach_by_scanning(struct ubi_device *ubi) { int err; struct ubi_scan_info *si; si = ubi_scan(ubi); if (IS_ERR(si)) return PTR_ERR(si); ubi->bad_peb_count = si->bad_peb_count; ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count; ubi->corr_peb_count = si->corr_peb_count; ubi->max_ec = si->max_ec; ubi->mean_ec = si->mean_ec; ubi_msg("max. sequence number: %llu", si->max_sqnum); err = ubi_read_volume_table(ubi, si); if (err) goto out_si; err = ubi_wl_init_scan(ubi, si); if (err) goto out_vtbl; err = ubi_eba_init_scan(ubi, si); if (err) goto out_wl; ubi_scan_destroy_si(si); return 0; out_wl: ubi_wl_close(ubi); out_vtbl: free_internal_volumes(ubi); vfree(ubi->vtbl); out_si: ubi_scan_destroy_si(si); return err; } /** * io_init - initialize I/O sub-system for a given UBI device. * @ubi: UBI device description object * * If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are * assumed: * o EC header is always at offset zero - this cannot be changed; * o VID header starts just after the EC header at the closest address * aligned to @io->hdrs_min_io_size; * o data starts just after the VID header at the closest address aligned to * @io->min_io_size * * This function returns zero in case of success and a negative error code in * case of failure. */ static int io_init(struct ubi_device *ubi) { if (ubi->mtd->numeraseregions != 0) { /* * Some flashes have several erase regions. Different regions * may have different eraseblock size and other * characteristics. It looks like mostly multi-region flashes * have one "main" region and one or more small regions to * store boot loader code or boot parameters or whatever. I * guess we should just pick the largest region. But this is * not implemented. */ ubi_err("multiple regions, not implemented"); return -EINVAL; } if (ubi->vid_hdr_offset < 0) return -EINVAL; /* * Note, in this implementation we support MTD devices with 0x7FFFFFFF * physical eraseblocks maximum. */ ubi->peb_size = ubi->mtd->erasesize; ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd); ubi->flash_size = ubi->mtd->size; if (ubi->mtd->block_isbad && ubi->mtd->block_markbad) ubi->bad_allowed = 1; if (ubi->mtd->type == MTD_NORFLASH) { ubi_assert(ubi->mtd->writesize == 1); ubi->nor_flash = 1; } ubi->min_io_size = ubi->mtd->writesize; ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft; /* * Make sure minimal I/O unit is power of 2. Note, there is no * fundamental reason for this assumption. It is just an optimization * which allows us to avoid costly division operations. */ if (!is_power_of_2(ubi->min_io_size)) { ubi_err("min. I/O unit (%d) is not power of 2", ubi->min_io_size); return -EINVAL; } ubi_assert(ubi->hdrs_min_io_size > 0); ubi_assert(ubi->hdrs_min_io_size <= ubi->min_io_size); ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0); /* Calculate default aligned sizes of EC and VID headers */ ubi->ec_hdr_alsize = ALIGN(UBI_EC_HDR_SIZE, ubi->hdrs_min_io_size); ubi->vid_hdr_alsize = ALIGN(UBI_VID_HDR_SIZE, ubi->hdrs_min_io_size); dbg_msg("min_io_size %d", ubi->min_io_size); dbg_msg("hdrs_min_io_size %d", ubi->hdrs_min_io_size); dbg_msg("ec_hdr_alsize %d", ubi->ec_hdr_alsize); dbg_msg("vid_hdr_alsize %d", ubi->vid_hdr_alsize); if (ubi->vid_hdr_offset == 0) /* Default offset */ ubi->vid_hdr_offset = ubi->vid_hdr_aloffset = ubi->ec_hdr_alsize; else { ubi->vid_hdr_aloffset = ubi->vid_hdr_offset & ~(ubi->hdrs_min_io_size - 1); ubi->vid_hdr_shift = ubi->vid_hdr_offset - ubi->vid_hdr_aloffset; } /* Similar for the data offset */ ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE; ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size); dbg_msg("vid_hdr_offset %d", ubi->vid_hdr_offset); dbg_msg("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset); dbg_msg("vid_hdr_shift %d", ubi->vid_hdr_shift); dbg_msg("leb_start %d", ubi->leb_start); /* The shift must be aligned to 32-bit boundary */ if (ubi->vid_hdr_shift % 4) { ubi_err("unaligned VID header shift %d", ubi->vid_hdr_shift); return -EINVAL; } /* Check sanity */ if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE || ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE || ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE || ubi->leb_start & (ubi->min_io_size - 1)) { ubi_err("bad VID header (%d) or data offsets (%d)", ubi->vid_hdr_offset, ubi->leb_start); return -EINVAL; } /* * Set maximum amount of physical erroneous eraseblocks to be 10%. * Erroneous PEB are those which have read errors. */ ubi->max_erroneous = ubi->peb_count / 10; if (ubi->max_erroneous < 16) ubi->max_erroneous = 16; dbg_msg("max_erroneous %d", ubi->max_erroneous); /* * It may happen that EC and VID headers are situated in one minimal * I/O unit. In this case we can only accept this UBI image in * read-only mode. */ if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) { ubi_warn("EC and VID headers are in the same minimal I/O unit, " "switch to read-only mode"); ubi->ro_mode = 1; } ubi->leb_size = ubi->peb_size - ubi->leb_start; if (!(ubi->mtd->flags & MTD_WRITEABLE)) { ubi_msg("MTD device %d is write-protected, attach in " "read-only mode", ubi->mtd->index); ubi->ro_mode = 1; } ubi_msg("physical eraseblock size: %d bytes (%d KiB)", ubi->peb_size, ubi->peb_size >> 10); ubi_msg("logical eraseblock size: %d bytes", ubi->leb_size); ubi_msg("smallest flash I/O unit: %d", ubi->min_io_size); if (ubi->hdrs_min_io_size != ubi->min_io_size) ubi_msg("sub-page size: %d", ubi->hdrs_min_io_size); ubi_msg("VID header offset: %d (aligned %d)", ubi->vid_hdr_offset, ubi->vid_hdr_aloffset); ubi_msg("data offset: %d", ubi->leb_start); /* * Note, ideally, we have to initialize ubi->bad_peb_count here. But * unfortunately, MTD does not provide this information. We should loop * over all physical eraseblocks and invoke mtd->block_is_bad() for * each physical eraseblock. So, we skip ubi->bad_peb_count * uninitialized and initialize it after scanning. */ return 0; } /** * autoresize - re-size the volume which has the "auto-resize" flag set. * @ubi: UBI device description object * @vol_id: ID of the volume to re-size * * This function re-sizes the volume marked by the @UBI_VTBL_AUTORESIZE_FLG in * the volume table to the largest possible size. See comments in ubi-header.h * for more description of the flag. Returns zero in case of success and a * negative error code in case of failure. */ static int autoresize(struct ubi_device *ubi, int vol_id) { struct ubi_volume_desc desc; struct ubi_volume *vol = ubi->volumes[vol_id]; int err, old_reserved_pebs = vol->reserved_pebs; /* * Clear the auto-resize flag in the volume in-memory copy of the * volume table, and 'ubi_resize_volume()' will propagate this change * to the flash. */ ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG; if (ubi->avail_pebs == 0) { struct ubi_vtbl_record vtbl_rec; /* * No available PEBs to re-size the volume, clear the flag on * flash and exit. */ memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record)); err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); if (err) ubi_err("cannot clean auto-resize flag for volume %d", vol_id); } else { desc.vol = vol; err = ubi_resize_volume(&desc, old_reserved_pebs + ubi->avail_pebs); if (err) ubi_err("cannot auto-resize volume %d", vol_id); } if (err) return err; ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id, vol->name, old_reserved_pebs, vol->reserved_pebs); return 0; } /** * ubi_attach_mtd_dev - attach an MTD device. * @mtd: MTD device description object * @ubi_num: number to assign to the new UBI device * @vid_hdr_offset: VID header offset * * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in * which case this function finds a vacant device number and assigns it * automatically. Returns the new UBI device number in case of success and a * negative error code in case of failure. * * Note, the invocations of this function has to be serialized by the * @ubi_devices_mutex. */ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset) { struct ubi_device *ubi; int i, err, ref = 0; /* * Check if we already have the same MTD device attached. * * Note, this function assumes that UBI devices creations and deletions * are serialized, so it does not take the &ubi_devices_lock. */ for (i = 0; i < UBI_MAX_DEVICES; i++) { ubi = ubi_devices[i]; if (ubi && mtd->index == ubi->mtd->index) { dbg_err("mtd%d is already attached to ubi%d", mtd->index, i); return -EEXIST; } } /* * Make sure this MTD device is not emulated on top of an UBI volume * already. Well, generally this recursion works fine, but there are * different problems like the UBI module takes a reference to itself * by attaching (and thus, opening) the emulated MTD device. This * results in inability to unload the module. And in general it makes * no sense to attach emulated MTD devices, so we prohibit this. */ if (mtd->type == MTD_UBIVOLUME) { ubi_err("refuse attaching mtd%d - it is already emulated on " "top of UBI", mtd->index); return -EINVAL; } if (ubi_num == UBI_DEV_NUM_AUTO) { /* Search for an empty slot in the @ubi_devices array */ for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++) if (!ubi_devices[ubi_num]) break; if (ubi_num == UBI_MAX_DEVICES) { dbg_err("only %d UBI devices may be created", UBI_MAX_DEVICES); return -ENFILE; } } else { if (ubi_num >= UBI_MAX_DEVICES) return -EINVAL; /* Make sure ubi_num is not busy */ if (ubi_devices[ubi_num]) { dbg_err("ubi%d already exists", ubi_num); return -EEXIST; } } ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL); if (!ubi) return -ENOMEM; ubi->mtd = mtd; ubi->ubi_num = ubi_num; ubi->vid_hdr_offset = vid_hdr_offset; ubi->autoresize_vol_id = -1; mutex_init(&ubi->buf_mutex); mutex_init(&ubi->ckvol_mutex); mutex_init(&ubi->device_mutex); spin_lock_init(&ubi->volumes_lock); ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num); dbg_msg("sizeof(struct ubi_scan_leb) %zu", sizeof(struct ubi_scan_leb)); dbg_msg("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry)); err = io_init(ubi); if (err) goto out_free; err = -ENOMEM; ubi->peb_buf1 = vmalloc(ubi->peb_size); if (!ubi->peb_buf1) goto out_free; ubi->peb_buf2 = vmalloc(ubi->peb_size); if (!ubi->peb_buf2) goto out_free; err = attach_by_scanning(ubi); if (err) { dbg_err("failed to attach by scanning, error %d", err); goto out_free; } if (ubi->autoresize_vol_id != -1) { err = autoresize(ubi, ubi->autoresize_vol_id); if (err) goto out_detach; } err = uif_init(ubi, &ref); if (err) goto out_detach; ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name); if (IS_ERR(ubi->bgt_thread)) { err = PTR_ERR(ubi->bgt_thread); ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name, err); goto out_uif; } ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num); ubi_msg("MTD device name: \"%s\"", mtd->name); ubi_msg("MTD device size: %llu MiB", ubi->flash_size >> 20); ubi_msg("number of good PEBs: %d", ubi->good_peb_count); ubi_msg("number of bad PEBs: %d", ubi->bad_peb_count); ubi_msg("number of corrupted PEBs: %d", ubi->corr_peb_count); ubi_msg("max. allowed volumes: %d", ubi->vtbl_slots); ubi_msg("wear-leveling threshold: %d", CONFIG_MTD_UBI_WL_THRESHOLD); ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT); ubi_msg("number of user volumes: %d", ubi->vol_count - UBI_INT_VOL_COUNT); ubi_msg("available PEBs: %d", ubi->avail_pebs); ubi_msg("total number of reserved PEBs: %d", ubi->rsvd_pebs); ubi_msg("number of PEBs reserved for bad PEB handling: %d", ubi->beb_rsvd_pebs); ubi_msg("max/mean erase counter: %d/%d", ubi->max_ec, ubi->mean_ec); ubi_msg("image sequence number: %d", ubi->image_seq); /* * The below lock makes sure we do not race with 'ubi_thread()' which * checks @ubi->thread_enabled. Otherwise we may fail to wake it up. */ spin_lock(&ubi->wl_lock); ubi->thread_enabled = 1; wake_up_process(ubi->bgt_thread); spin_unlock(&ubi->wl_lock); ubi_devices[ubi_num] = ubi; ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL); return ubi_num; out_uif: uif_close(ubi); out_detach: ubi_wl_close(ubi); free_internal_volumes(ubi); vfree(ubi->vtbl); out_free: vfree(ubi->peb_buf1); vfree(ubi->peb_buf2); if (ref) put_device(&ubi->dev); else kfree(ubi); return err; } /** * ubi_detach_mtd_dev - detach an MTD device. * @ubi_num: UBI device number to detach from * @anyway: detach MTD even if device reference count is not zero * * This function destroys an UBI device number @ubi_num and detaches the * underlying MTD device. Returns zero in case of success and %-EBUSY if the * UBI device is busy and cannot be destroyed, and %-EINVAL if it does not * exist. * * Note, the invocations of this function has to be serialized by the * @ubi_devices_mutex. */ int ubi_detach_mtd_dev(int ubi_num, int anyway) { struct ubi_device *ubi; if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) return -EINVAL; ubi = ubi_get_device(ubi_num); if (!ubi) return -EINVAL; spin_lock(&ubi_devices_lock); put_device(&ubi->dev); ubi->ref_count -= 1; if (ubi->ref_count) { if (!anyway) { spin_unlock(&ubi_devices_lock); return -EBUSY; } /* This may only happen if there is a bug */ ubi_err("%s reference count %d, destroy anyway", ubi->ubi_name, ubi->ref_count); } ubi_devices[ubi_num] = NULL; spin_unlock(&ubi_devices_lock); ubi_assert(ubi_num == ubi->ubi_num); ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL); dbg_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num); /* * Before freeing anything, we have to stop the background thread to * prevent it from doing anything on this device while we are freeing. */ if (ubi->bgt_thread) kthread_stop(ubi->bgt_thread); /* * Get a reference to the device in order to prevent 'dev_release()' * from freeing the @ubi object. */ get_device(&ubi->dev); uif_close(ubi); ubi_wl_close(ubi); free_internal_volumes(ubi); vfree(ubi->vtbl); put_mtd_device(ubi->mtd); vfree(ubi->peb_buf1); vfree(ubi->peb_buf2); ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num); put_device(&ubi->dev); return 0; } /** * open_mtd_by_chdev - open an MTD device by its character device node path. * @mtd_dev: MTD character device node path * * This helper function opens an MTD device by its character node device path. * Returns MTD device description object in case of success and a negative * error code in case of failure. */ static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev) { int err, major, minor, mode; struct path path; /* Probably this is an MTD character device node path */ err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path); if (err) return ERR_PTR(err); /* MTD device number is defined by the major / minor numbers */ major = imajor(path.dentry->d_inode); minor = iminor(path.dentry->d_inode); mode = path.dentry->d_inode->i_mode; path_put(&path); if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode)) return ERR_PTR(-EINVAL); if (minor & 1) /* * Just do not think the "/dev/mtdrX" devices support is need, * so do not support them to avoid doing extra work. */ return ERR_PTR(-EINVAL); return get_mtd_device(NULL, minor / 2); } /** * open_mtd_device - open MTD device by name, character device path, or number. * @mtd_dev: name, character device node path, or MTD device device number * * This function tries to open and MTD device described by @mtd_dev string, * which is first treated as ASCII MTD device number, and if it is not true, it * is treated as MTD device name, and if that is also not true, it is treated * as MTD character device node path. Returns MTD device description object in * case of success and a negative error code in case of failure. */ static struct mtd_info * __init open_mtd_device(const char *mtd_dev) { struct mtd_info *mtd; int mtd_num; char *endp; mtd_num = simple_strtoul(mtd_dev, &endp, 0); if (*endp != '\0' || mtd_dev == endp) { /* * This does not look like an ASCII integer, probably this is * MTD device name. */ mtd = get_mtd_device_nm(mtd_dev); if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV) /* Probably this is an MTD character device node path */ mtd = open_mtd_by_chdev(mtd_dev); } else mtd = get_mtd_device(NULL, mtd_num); return mtd; } static int __init ubi_init(void) { int err, i, k; /* Ensure that EC and VID headers have correct size */ BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64); BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64); if (mtd_devs > UBI_MAX_DEVICES) { ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES); return -EINVAL; } /* Create base sysfs directory and sysfs files */ ubi_class = class_create(THIS_MODULE, UBI_NAME_STR); if (IS_ERR(ubi_class)) { err = PTR_ERR(ubi_class); ubi_err("cannot create UBI class"); goto out; } err = class_create_file(ubi_class, &ubi_version); if (err) { ubi_err("cannot create sysfs file"); goto out_class; } err = misc_register(&ubi_ctrl_cdev); if (err) { ubi_err("cannot register device"); goto out_version; } ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", sizeof(struct ubi_wl_entry), 0, 0, NULL); if (!ubi_wl_entry_slab) goto out_dev_unreg; /* Attach MTD devices */ for (i = 0; i < mtd_devs; i++) { struct mtd_dev_param *p = &mtd_dev_param[i]; struct mtd_info *mtd; cond_resched(); mtd = open_mtd_device(p->name); if (IS_ERR(mtd)) { err = PTR_ERR(mtd); goto out_detach; } mutex_lock(&ubi_devices_mutex); err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, p->vid_hdr_offs); mutex_unlock(&ubi_devices_mutex); if (err < 0) { ubi_err("cannot attach mtd%d", mtd->index); put_mtd_device(mtd); /* * Originally UBI stopped initializing on any error. * However, later on it was found out that this * behavior is not very good when UBI is compiled into * the kernel and the MTD devices to attach are passed * through the command line. Indeed, UBI failure * stopped whole boot sequence. * * To fix this, we changed the behavior for the * non-module case, but preserved the old behavior for * the module case, just for compatibility. This is a * little inconsistent, though. */ if (ubi_is_module()) goto out_detach; } } return 0; out_detach: for (k = 0; k < i; k++) if (ubi_devices[k]) { mutex_lock(&ubi_devices_mutex); ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1); mutex_unlock(&ubi_devices_mutex); } kmem_cache_destroy(ubi_wl_entry_slab); out_dev_unreg: misc_deregister(&ubi_ctrl_cdev); out_version: class_remove_file(ubi_class, &ubi_version); out_class: class_destroy(ubi_class); out: ubi_err("UBI error: cannot initialize UBI, error %d", err); return err; } module_init(ubi_init); static void __exit ubi_exit(void) { int i; for (i = 0; i < UBI_MAX_DEVICES; i++) if (ubi_devices[i]) { mutex_lock(&ubi_devices_mutex); ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1); mutex_unlock(&ubi_devices_mutex); } kmem_cache_destroy(ubi_wl_entry_slab); misc_deregister(&ubi_ctrl_cdev); class_remove_file(ubi_class, &ubi_version); class_destroy(ubi_class); } module_exit(ubi_exit); /** * bytes_str_to_int - convert a number of bytes string into an integer. * @str: the string to convert * * This function returns positive resulting integer in case of success and a * negative error code in case of failure. */ static int __init bytes_str_to_int(const char *str) { char *endp; unsigned long result; result = simple_strtoul(str, &endp, 0); if (str == endp || result >= INT_MAX) { printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n", str); return -EINVAL; } switch (*endp) { case 'G': result *= 1024; case 'M': result *= 1024; case 'K': result *= 1024; if (endp[1] == 'i' && endp[2] == 'B') endp += 2; case '\0': break; default: printk(KERN_ERR "UBI error: incorrect bytes count: \"%s\"\n", str); return -EINVAL; } return result; } /** * ubi_mtd_param_parse - parse the 'mtd=' UBI parameter. * @val: the parameter value to parse * @kp: not used * * This function returns zero in case of success and a negative error code in * case of error. */ static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp) { int i, len; struct mtd_dev_param *p; char buf[MTD_PARAM_LEN_MAX]; char *pbuf = &buf[0]; char *tokens[2] = {NULL, NULL}; if (!val) return -EINVAL; if (mtd_devs == UBI_MAX_DEVICES) { printk(KERN_ERR "UBI error: too many parameters, max. is %d\n", UBI_MAX_DEVICES); return -EINVAL; } len = strnlen(val, MTD_PARAM_LEN_MAX); if (len == MTD_PARAM_LEN_MAX) { printk(KERN_ERR "UBI error: parameter \"%s\" is too long, " "max. is %d\n", val, MTD_PARAM_LEN_MAX); return -EINVAL; } if (len == 0) { printk(KERN_WARNING "UBI warning: empty 'mtd=' parameter - " "ignored\n"); return 0; } strcpy(buf, val); /* Get rid of the final newline */ if (buf[len - 1] == '\n') buf[len - 1] = '\0'; for (i = 0; i < 2; i++) tokens[i] = strsep(&pbuf, ","); if (pbuf) { printk(KERN_ERR "UBI error: too many arguments at \"%s\"\n", val); return -EINVAL; } p = &mtd_dev_param[mtd_devs]; strcpy(&p->name[0], tokens[0]); if (tokens[1]) p->vid_hdr_offs = bytes_str_to_int(tokens[1]); if (p->vid_hdr_offs < 0) return p->vid_hdr_offs; mtd_devs += 1; return 0; } module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000); MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: " "mtd=[,].\n" "Multiple \"mtd\" parameters may be specified.\n" "MTD devices may be specified by their number, name, or " "path to the MTD character device node.\n" "Optional \"vid_hdr_offs\" parameter specifies UBI VID " "header position to be used by UBI.\n" "Example 1: mtd=/dev/mtd0 - attach MTD device " "/dev/mtd0.\n" "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."); MODULE_VERSION(__stringify(UBI_VERSION)); MODULE_DESCRIPTION("UBI - Unsorted Block Images"); MODULE_AUTHOR("Artem Bityutskiy"); MODULE_LICENSE("GPL");