diff options
Diffstat (limited to 'drivers/mtd/ubi/cdev.c')
| -rw-r--r-- | drivers/mtd/ubi/cdev.c | 1108 |
1 files changed, 1108 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c new file mode 100644 index 000000000..cc9a28cf9 --- /dev/null +++ b/drivers/mtd/ubi/cdev.c @@ -0,0 +1,1108 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file includes implementation of UBI character device operations. + * + * There are two kinds of character devices in UBI: UBI character devices and + * UBI volume character devices. UBI character devices allow users to + * manipulate whole volumes: create, remove, and re-size them. Volume character + * devices provide volume I/O capabilities. + * + * Major and minor numbers are assigned dynamically to both UBI and volume + * character devices. + * + * Well, there is the third kind of character devices - the UBI control + * character device, which allows to manipulate by UBI devices - create and + * delete them. In other words, it is used for attaching and detaching MTD + * devices. + */ + +#include <linux/module.h> +#include <linux/stat.h> +#include <linux/slab.h> +#include <linux/ioctl.h> +#include <linux/capability.h> +#include <linux/uaccess.h> +#include <linux/compat.h> +#include <linux/math64.h> +#include <mtd/ubi-user.h> +#include "ubi.h" + +/** + * get_exclusive - get exclusive access to an UBI volume. + * @desc: volume descriptor + * + * This function changes UBI volume open mode to "exclusive". Returns previous + * mode value (positive integer) in case of success and a negative error code + * in case of failure. + */ +static int get_exclusive(struct ubi_volume_desc *desc) +{ + int users, err; + struct ubi_volume *vol = desc->vol; + + spin_lock(&vol->ubi->volumes_lock); + users = vol->readers + vol->writers + vol->exclusive + vol->metaonly; + ubi_assert(users > 0); + if (users > 1) { + ubi_err(vol->ubi, "%d users for volume %d", users, vol->vol_id); + err = -EBUSY; + } else { + vol->readers = vol->writers = vol->metaonly = 0; + vol->exclusive = 1; + err = desc->mode; + desc->mode = UBI_EXCLUSIVE; + } + spin_unlock(&vol->ubi->volumes_lock); + + return err; +} + +/** + * revoke_exclusive - revoke exclusive mode. + * @desc: volume descriptor + * @mode: new mode to switch to + */ +static void revoke_exclusive(struct ubi_volume_desc *desc, int mode) +{ + struct ubi_volume *vol = desc->vol; + + spin_lock(&vol->ubi->volumes_lock); + ubi_assert(vol->readers == 0 && vol->writers == 0 && vol->metaonly == 0); + ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE); + vol->exclusive = 0; + if (mode == UBI_READONLY) + vol->readers = 1; + else if (mode == UBI_READWRITE) + vol->writers = 1; + else if (mode == UBI_METAONLY) + vol->metaonly = 1; + else + vol->exclusive = 1; + spin_unlock(&vol->ubi->volumes_lock); + + desc->mode = mode; +} + +static int vol_cdev_open(struct inode *inode, struct file *file) +{ + struct ubi_volume_desc *desc; + int vol_id = iminor(inode) - 1, mode, ubi_num; + + ubi_num = ubi_major2num(imajor(inode)); + if (ubi_num < 0) + return ubi_num; + + if (file->f_mode & FMODE_WRITE) + mode = UBI_READWRITE; + else + mode = UBI_READONLY; + + dbg_gen("open device %d, volume %d, mode %d", + ubi_num, vol_id, mode); + + desc = ubi_open_volume(ubi_num, vol_id, mode); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + file->private_data = desc; + return 0; +} + +static int vol_cdev_release(struct inode *inode, struct file *file) +{ + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + + dbg_gen("release device %d, volume %d, mode %d", + vol->ubi->ubi_num, vol->vol_id, desc->mode); + + if (vol->updating) { + ubi_warn(vol->ubi, "update of volume %d not finished, volume is damaged", + vol->vol_id); + ubi_assert(!vol->changing_leb); + vol->updating = 0; + vfree(vol->upd_buf); + } else if (vol->changing_leb) { + dbg_gen("only %lld of %lld bytes received for atomic LEB change for volume %d:%d, cancel", + vol->upd_received, vol->upd_bytes, vol->ubi->ubi_num, + vol->vol_id); + vol->changing_leb = 0; + vfree(vol->upd_buf); + } + + ubi_close_volume(desc); + return 0; +} + +static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin) +{ + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + + if (vol->updating) { + /* Update is in progress, seeking is prohibited */ + ubi_err(vol->ubi, "updating"); + return -EBUSY; + } + + return fixed_size_llseek(file, offset, origin, vol->used_bytes); +} + +static int vol_cdev_fsync(struct file *file, loff_t start, loff_t end, + int datasync) +{ + struct ubi_volume_desc *desc = file->private_data; + struct ubi_device *ubi = desc->vol->ubi; + struct inode *inode = file_inode(file); + int err; + inode_lock(inode); + err = ubi_sync(ubi->ubi_num); + inode_unlock(inode); + return err; +} + + +static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count, + loff_t *offp) +{ + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err, lnum, off, len, tbuf_size; + size_t count_save = count; + void *tbuf; + + dbg_gen("read %zd bytes from offset %lld of volume %d", + count, *offp, vol->vol_id); + + if (vol->updating) { + ubi_err(vol->ubi, "updating"); + return -EBUSY; + } + if (vol->upd_marker) { + ubi_err(vol->ubi, "damaged volume, update marker is set"); + return -EBADF; + } + if (*offp == vol->used_bytes || count == 0) + return 0; + + if (vol->corrupted) + dbg_gen("read from corrupted volume %d", vol->vol_id); + + if (*offp + count > vol->used_bytes) + count_save = count = vol->used_bytes - *offp; + + tbuf_size = vol->usable_leb_size; + if (count < tbuf_size) + tbuf_size = ALIGN(count, ubi->min_io_size); + tbuf = vmalloc(tbuf_size); + if (!tbuf) + return -ENOMEM; + + len = count > tbuf_size ? tbuf_size : count; + lnum = div_u64_rem(*offp, vol->usable_leb_size, &off); + + do { + cond_resched(); + + if (off + len >= vol->usable_leb_size) + len = vol->usable_leb_size - off; + + err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0); + if (err) + break; + + off += len; + if (off == vol->usable_leb_size) { + lnum += 1; + off -= vol->usable_leb_size; + } + + count -= len; + *offp += len; + + err = copy_to_user(buf, tbuf, len); + if (err) { + err = -EFAULT; + break; + } + + buf += len; + len = count > tbuf_size ? tbuf_size : count; + } while (count); + + vfree(tbuf); + return err ? err : count_save - count; +} + +/* + * This function allows to directly write to dynamic UBI volumes, without + * issuing the volume update operation. + */ +static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf, + size_t count, loff_t *offp) +{ + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int lnum, off, len, tbuf_size, err = 0; + size_t count_save = count; + char *tbuf; + + if (!vol->direct_writes) + return -EPERM; + + dbg_gen("requested: write %zd bytes to offset %lld of volume %u", + count, *offp, vol->vol_id); + + if (vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + lnum = div_u64_rem(*offp, vol->usable_leb_size, &off); + if (off & (ubi->min_io_size - 1)) { + ubi_err(ubi, "unaligned position"); + return -EINVAL; + } + + if (*offp + count > vol->used_bytes) + count_save = count = vol->used_bytes - *offp; + + /* We can write only in fractions of the minimum I/O unit */ + if (count & (ubi->min_io_size - 1)) { + ubi_err(ubi, "unaligned write length"); + return -EINVAL; + } + + tbuf_size = vol->usable_leb_size; + if (count < tbuf_size) + tbuf_size = ALIGN(count, ubi->min_io_size); + tbuf = vmalloc(tbuf_size); + if (!tbuf) + return -ENOMEM; + + len = count > tbuf_size ? tbuf_size : count; + + while (count) { + cond_resched(); + + if (off + len >= vol->usable_leb_size) + len = vol->usable_leb_size - off; + + err = copy_from_user(tbuf, buf, len); + if (err) { + err = -EFAULT; + break; + } + + err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len); + if (err) + break; + + off += len; + if (off == vol->usable_leb_size) { + lnum += 1; + off -= vol->usable_leb_size; + } + + count -= len; + *offp += len; + buf += len; + len = count > tbuf_size ? tbuf_size : count; + } + + vfree(tbuf); + return err ? err : count_save - count; +} + +static ssize_t vol_cdev_write(struct file *file, const char __user *buf, + size_t count, loff_t *offp) +{ + int err = 0; + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + if (!vol->updating && !vol->changing_leb) + return vol_cdev_direct_write(file, buf, count, offp); + + if (vol->updating) + err = ubi_more_update_data(ubi, vol, buf, count); + else + err = ubi_more_leb_change_data(ubi, vol, buf, count); + + if (err < 0) { + ubi_err(ubi, "cannot accept more %zd bytes of data, error %d", + count, err); + return err; + } + + if (err) { + /* + * The operation is finished, @err contains number of actually + * written bytes. + */ + count = err; + + if (vol->changing_leb) { + revoke_exclusive(desc, UBI_READWRITE); + return count; + } + + /* + * We voluntarily do not take into account the skip_check flag + * as we want to make sure what we wrote was correctly written. + */ + err = ubi_check_volume(ubi, vol->vol_id); + if (err < 0) + return err; + + if (err) { + ubi_warn(ubi, "volume %d on UBI device %d is corrupted", + vol->vol_id, ubi->ubi_num); + vol->corrupted = 1; + } + vol->checked = 1; + ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED); + revoke_exclusive(desc, UBI_READWRITE); + } + + return count; +} + +static long vol_cdev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int err = 0; + struct ubi_volume_desc *desc = file->private_data; + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + void __user *argp = (void __user *)arg; + + switch (cmd) { + /* Volume update command */ + case UBI_IOCVOLUP: + { + int64_t bytes, rsvd_bytes; + + if (!capable(CAP_SYS_RESOURCE)) { + err = -EPERM; + break; + } + + err = copy_from_user(&bytes, argp, sizeof(int64_t)); + if (err) { + err = -EFAULT; + break; + } + + if (desc->mode == UBI_READONLY) { + err = -EROFS; + break; + } + + rsvd_bytes = (long long)vol->reserved_pebs * + vol->usable_leb_size; + if (bytes < 0 || bytes > rsvd_bytes) { + err = -EINVAL; + break; + } + + err = get_exclusive(desc); + if (err < 0) + break; + + err = ubi_start_update(ubi, vol, bytes); + if (bytes == 0) { + ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED); + revoke_exclusive(desc, UBI_READWRITE); + } + break; + } + + /* Atomic logical eraseblock change command */ + case UBI_IOCEBCH: + { + struct ubi_leb_change_req req; + + err = copy_from_user(&req, argp, + sizeof(struct ubi_leb_change_req)); + if (err) { + err = -EFAULT; + break; + } + + if (desc->mode == UBI_READONLY || + vol->vol_type == UBI_STATIC_VOLUME) { + err = -EROFS; + break; + } + + /* Validate the request */ + err = -EINVAL; + if (!ubi_leb_valid(vol, req.lnum) || + req.bytes < 0 || req.bytes > vol->usable_leb_size) + break; + + err = get_exclusive(desc); + if (err < 0) + break; + + err = ubi_start_leb_change(ubi, vol, &req); + if (req.bytes == 0) + revoke_exclusive(desc, UBI_READWRITE); + break; + } + + /* Logical eraseblock erasure command */ + case UBI_IOCEBER: + { + int32_t lnum; + + err = get_user(lnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + if (desc->mode == UBI_READONLY || + vol->vol_type == UBI_STATIC_VOLUME) { + err = -EROFS; + break; + } + + if (!ubi_leb_valid(vol, lnum)) { + err = -EINVAL; + break; + } + + dbg_gen("erase LEB %d:%d", vol->vol_id, lnum); + err = ubi_eba_unmap_leb(ubi, vol, lnum); + if (err) + break; + + err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL); + break; + } + + /* Logical eraseblock map command */ + case UBI_IOCEBMAP: + { + struct ubi_map_req req; + + err = copy_from_user(&req, argp, sizeof(struct ubi_map_req)); + if (err) { + err = -EFAULT; + break; + } + err = ubi_leb_map(desc, req.lnum); + break; + } + + /* Logical eraseblock un-map command */ + case UBI_IOCEBUNMAP: + { + int32_t lnum; + + err = get_user(lnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + err = ubi_leb_unmap(desc, lnum); + break; + } + + /* Check if logical eraseblock is mapped command */ + case UBI_IOCEBISMAP: + { + int32_t lnum; + + err = get_user(lnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + err = ubi_is_mapped(desc, lnum); + break; + } + + /* Set volume property command */ + case UBI_IOCSETVOLPROP: + { + struct ubi_set_vol_prop_req req; + + err = copy_from_user(&req, argp, + sizeof(struct ubi_set_vol_prop_req)); + if (err) { + err = -EFAULT; + break; + } + switch (req.property) { + case UBI_VOL_PROP_DIRECT_WRITE: + mutex_lock(&ubi->device_mutex); + desc->vol->direct_writes = !!req.value; + mutex_unlock(&ubi->device_mutex); + break; + default: + err = -EINVAL; + break; + } + break; + } + + /* Create a R/O block device on top of the UBI volume */ + case UBI_IOCVOLCRBLK: + { + struct ubi_volume_info vi; + + ubi_get_volume_info(desc, &vi); + err = ubiblock_create(&vi); + break; + } + + /* Remove the R/O block device */ + case UBI_IOCVOLRMBLK: + { + struct ubi_volume_info vi; + + ubi_get_volume_info(desc, &vi); + err = ubiblock_remove(&vi); + break; + } + + default: + err = -ENOTTY; + break; + } + return err; +} + +/** + * verify_mkvol_req - verify volume creation request. + * @ubi: UBI device description object + * @req: the request to check + * + * This function zero if the request is correct, and %-EINVAL if not. + */ +static int verify_mkvol_req(const struct ubi_device *ubi, + const struct ubi_mkvol_req *req) +{ + int n, err = -EINVAL; + + if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 || + req->name_len < 0) + goto bad; + + if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) && + req->vol_id != UBI_VOL_NUM_AUTO) + goto bad; + + if (req->alignment == 0) + goto bad; + + if (req->bytes == 0) + goto bad; + + if (req->vol_type != UBI_DYNAMIC_VOLUME && + req->vol_type != UBI_STATIC_VOLUME) + goto bad; + + if (req->flags & ~UBI_VOL_VALID_FLGS) + goto bad; + + if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG && + req->vol_type != UBI_STATIC_VOLUME) + goto bad; + + if (req->alignment > ubi->leb_size) + goto bad; + + n = req->alignment & (ubi->min_io_size - 1); + if (req->alignment != 1 && n) + goto bad; + + if (!req->name[0] || !req->name_len) + goto bad; + + if (req->name_len > UBI_VOL_NAME_MAX) { + err = -ENAMETOOLONG; + goto bad; + } + + n = strnlen(req->name, req->name_len + 1); + if (n != req->name_len) + goto bad; + + return 0; + +bad: + ubi_err(ubi, "bad volume creation request"); + ubi_dump_mkvol_req(req); + return err; +} + +/** + * verify_rsvol_req - verify volume re-size request. + * @ubi: UBI device description object + * @req: the request to check + * + * This function returns zero if the request is correct, and %-EINVAL if not. + */ +static int verify_rsvol_req(const struct ubi_device *ubi, + const struct ubi_rsvol_req *req) +{ + if (req->bytes <= 0) + return -EINVAL; + + if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) + return -EINVAL; + + return 0; +} + +/** + * rename_volumes - rename UBI volumes. + * @ubi: UBI device description object + * @req: volumes re-name request + * + * This is a helper function for the volume re-name IOCTL which validates the + * the request, opens the volume and calls corresponding volumes management + * function. Returns zero in case of success and a negative error code in case + * of failure. + */ +static int rename_volumes(struct ubi_device *ubi, + struct ubi_rnvol_req *req) +{ + int i, n, err; + struct list_head rename_list; + struct ubi_rename_entry *re, *re1; + + if (req->count < 0 || req->count > UBI_MAX_RNVOL) + return -EINVAL; + + if (req->count == 0) + return 0; + + /* Validate volume IDs and names in the request */ + for (i = 0; i < req->count; i++) { + if (req->ents[i].vol_id < 0 || + req->ents[i].vol_id >= ubi->vtbl_slots) + return -EINVAL; + if (req->ents[i].name_len < 0) + return -EINVAL; + if (req->ents[i].name_len > UBI_VOL_NAME_MAX) + return -ENAMETOOLONG; + req->ents[i].name[req->ents[i].name_len] = '\0'; + n = strlen(req->ents[i].name); + if (n != req->ents[i].name_len) + return -EINVAL; + } + + /* Make sure volume IDs and names are unique */ + for (i = 0; i < req->count - 1; i++) { + for (n = i + 1; n < req->count; n++) { + if (req->ents[i].vol_id == req->ents[n].vol_id) { + ubi_err(ubi, "duplicated volume id %d", + req->ents[i].vol_id); + return -EINVAL; + } + if (!strcmp(req->ents[i].name, req->ents[n].name)) { + ubi_err(ubi, "duplicated volume name \"%s\"", + req->ents[i].name); + return -EINVAL; + } + } + } + + /* Create the re-name list */ + INIT_LIST_HEAD(&rename_list); + for (i = 0; i < req->count; i++) { + int vol_id = req->ents[i].vol_id; + int name_len = req->ents[i].name_len; + const char *name = req->ents[i].name; + + re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); + if (!re) { + err = -ENOMEM; + goto out_free; + } + + re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_METAONLY); + if (IS_ERR(re->desc)) { + err = PTR_ERR(re->desc); + ubi_err(ubi, "cannot open volume %d, error %d", + vol_id, err); + kfree(re); + goto out_free; + } + + /* Skip this re-naming if the name does not really change */ + if (re->desc->vol->name_len == name_len && + !memcmp(re->desc->vol->name, name, name_len)) { + ubi_close_volume(re->desc); + kfree(re); + continue; + } + + re->new_name_len = name_len; + memcpy(re->new_name, name, name_len); + list_add_tail(&re->list, &rename_list); + dbg_gen("will rename volume %d from \"%s\" to \"%s\"", + vol_id, re->desc->vol->name, name); + } + + if (list_empty(&rename_list)) + return 0; + + /* Find out the volumes which have to be removed */ + list_for_each_entry(re, &rename_list, list) { + struct ubi_volume_desc *desc; + int no_remove_needed = 0; + + /* + * Volume @re->vol_id is going to be re-named to + * @re->new_name, while its current name is @name. If a volume + * with name @re->new_name currently exists, it has to be + * removed, unless it is also re-named in the request (@req). + */ + list_for_each_entry(re1, &rename_list, list) { + if (re->new_name_len == re1->desc->vol->name_len && + !memcmp(re->new_name, re1->desc->vol->name, + re1->desc->vol->name_len)) { + no_remove_needed = 1; + break; + } + } + + if (no_remove_needed) + continue; + + /* + * It seems we need to remove volume with name @re->new_name, + * if it exists. + */ + desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name, + UBI_EXCLUSIVE); + if (IS_ERR(desc)) { + err = PTR_ERR(desc); + if (err == -ENODEV) + /* Re-naming into a non-existing volume name */ + continue; + + /* The volume exists but busy, or an error occurred */ + ubi_err(ubi, "cannot open volume \"%s\", error %d", + re->new_name, err); + goto out_free; + } + + re1 = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); + if (!re1) { + err = -ENOMEM; + ubi_close_volume(desc); + goto out_free; + } + + re1->remove = 1; + re1->desc = desc; + list_add(&re1->list, &rename_list); + dbg_gen("will remove volume %d, name \"%s\"", + re1->desc->vol->vol_id, re1->desc->vol->name); + } + + mutex_lock(&ubi->device_mutex); + err = ubi_rename_volumes(ubi, &rename_list); + mutex_unlock(&ubi->device_mutex); + +out_free: + list_for_each_entry_safe(re, re1, &rename_list, list) { + ubi_close_volume(re->desc); + list_del(&re->list); + kfree(re); + } + return err; +} + +static long ubi_cdev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int err = 0; + struct ubi_device *ubi; + struct ubi_volume_desc *desc; + void __user *argp = (void __user *)arg; + + if (!capable(CAP_SYS_RESOURCE)) + return -EPERM; + + ubi = ubi_get_by_major(imajor(file->f_mapping->host)); + if (!ubi) + return -ENODEV; + + switch (cmd) { + /* Create volume command */ + case UBI_IOCMKVOL: + { + struct ubi_mkvol_req req; + + dbg_gen("create volume"); + err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req)); + if (err) { + err = -EFAULT; + break; + } + + err = verify_mkvol_req(ubi, &req); + if (err) + break; + + mutex_lock(&ubi->device_mutex); + err = ubi_create_volume(ubi, &req); + mutex_unlock(&ubi->device_mutex); + if (err) + break; + + err = put_user(req.vol_id, (__user int32_t *)argp); + if (err) + err = -EFAULT; + + break; + } + + /* Remove volume command */ + case UBI_IOCRMVOL: + { + int vol_id; + + dbg_gen("remove volume"); + err = get_user(vol_id, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE); + if (IS_ERR(desc)) { + err = PTR_ERR(desc); + break; + } + + mutex_lock(&ubi->device_mutex); + err = ubi_remove_volume(desc, 0); + mutex_unlock(&ubi->device_mutex); + + /* + * The volume is deleted (unless an error occurred), and the + * 'struct ubi_volume' object will be freed when + * 'ubi_close_volume()' will call 'put_device()'. + */ + ubi_close_volume(desc); + break; + } + + /* Re-size volume command */ + case UBI_IOCRSVOL: + { + int pebs; + struct ubi_rsvol_req req; + + dbg_gen("re-size volume"); + err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req)); + if (err) { + err = -EFAULT; + break; + } + + err = verify_rsvol_req(ubi, &req); + if (err) + break; + + desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE); + if (IS_ERR(desc)) { + err = PTR_ERR(desc); + break; + } + + pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1, + desc->vol->usable_leb_size); + + mutex_lock(&ubi->device_mutex); + err = ubi_resize_volume(desc, pebs); + mutex_unlock(&ubi->device_mutex); + ubi_close_volume(desc); + break; + } + + /* Re-name volumes command */ + case UBI_IOCRNVOL: + { + struct ubi_rnvol_req *req; + + dbg_gen("re-name volumes"); + req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL); + if (!req) { + err = -ENOMEM; + break; + } + + err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req)); + if (err) { + err = -EFAULT; + kfree(req); + break; + } + + err = rename_volumes(ubi, req); + kfree(req); + break; + } + + /* Check a specific PEB for bitflips and scrub it if needed */ + case UBI_IOCRPEB: + { + int pnum; + + err = get_user(pnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + err = ubi_bitflip_check(ubi, pnum, 0); + break; + } + + /* Force scrubbing for a specific PEB */ + case UBI_IOCSPEB: + { + int pnum; + + err = get_user(pnum, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + err = ubi_bitflip_check(ubi, pnum, 1); + break; + } + + default: + err = -ENOTTY; + break; + } + + ubi_put_device(ubi); + return err; +} + +static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int err = 0; + void __user *argp = (void __user *)arg; + + if (!capable(CAP_SYS_RESOURCE)) + return -EPERM; + + switch (cmd) { + /* Attach an MTD device command */ + case UBI_IOCATT: + { + struct ubi_attach_req req; + struct mtd_info *mtd; + + dbg_gen("attach MTD device"); + err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req)); + if (err) { + err = -EFAULT; + break; + } + + if (req.mtd_num < 0 || + (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) { + err = -EINVAL; + break; + } + + mtd = get_mtd_device(NULL, req.mtd_num); + if (IS_ERR(mtd)) { + err = PTR_ERR(mtd); + break; + } + + /* + * Note, further request verification is done by + * 'ubi_attach_mtd_dev()'. + */ + mutex_lock(&ubi_devices_mutex); + err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset, + req.max_beb_per1024); + mutex_unlock(&ubi_devices_mutex); + if (err < 0) + put_mtd_device(mtd); + else + /* @err contains UBI device number */ + err = put_user(err, (__user int32_t *)argp); + + break; + } + + /* Detach an MTD device command */ + case UBI_IOCDET: + { + int ubi_num; + + dbg_gen("detach MTD device"); + err = get_user(ubi_num, (__user int32_t *)argp); + if (err) { + err = -EFAULT; + break; + } + + mutex_lock(&ubi_devices_mutex); + err = ubi_detach_mtd_dev(ubi_num, 0); + mutex_unlock(&ubi_devices_mutex); + break; + } + + default: + err = -ENOTTY; + break; + } + + return err; +} + +/* UBI volume character device operations */ +const struct file_operations ubi_vol_cdev_operations = { + .owner = THIS_MODULE, + .open = vol_cdev_open, + .release = vol_cdev_release, + .llseek = vol_cdev_llseek, + .read = vol_cdev_read, + .write = vol_cdev_write, + .fsync = vol_cdev_fsync, + .unlocked_ioctl = vol_cdev_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +/* UBI character device operations */ +const struct file_operations ubi_cdev_operations = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .unlocked_ioctl = ubi_cdev_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +/* UBI control character device operations */ +const struct file_operations ubi_ctrl_cdev_operations = { + .owner = THIS_MODULE, + .unlocked_ioctl = ctrl_cdev_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .llseek = no_llseek, +}; |