v4.19.13 snapshot.
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
new file mode 100644
index 0000000..22547d7
--- /dev/null
+++ b/drivers/mtd/ubi/cdev.c
@@ -0,0 +1,1121 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2006
+ *
+ * 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)
+ */
+
+/*
+ * 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;
+ }
+
+ 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;
+}
+
+#ifdef CONFIG_COMPAT
+static long vol_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return vol_cdev_ioctl(file, cmd, translated_arg);
+}
+
+static long ubi_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return ubi_cdev_ioctl(file, cmd, translated_arg);
+}
+
+static long ctrl_cdev_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long translated_arg = (unsigned long)compat_ptr(arg);
+
+ return ctrl_cdev_ioctl(file, cmd, translated_arg);
+}
+#else
+#define vol_cdev_compat_ioctl NULL
+#define ubi_cdev_compat_ioctl NULL
+#define ctrl_cdev_compat_ioctl NULL
+#endif
+
+/* 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 = vol_cdev_compat_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 = ubi_cdev_compat_ioctl,
+};
+
+/* UBI control character device operations */
+const struct file_operations ubi_ctrl_cdev_operations = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = ctrl_cdev_ioctl,
+ .compat_ioctl = ctrl_cdev_compat_ioctl,
+ .llseek = no_llseek,
+};