summaryrefslogtreecommitdiff
path: root/target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch
diff options
context:
space:
mode:
Diffstat (limited to 'target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch')
-rw-r--r--target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch829
1 files changed, 0 insertions, 829 deletions
diff --git a/target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch b/target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch
deleted file mode 100644
index 609deec..0000000
--- a/target/linux/generic/patches-3.14/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch
+++ /dev/null
@@ -1,829 +0,0 @@
-From 9d54c8a33eec78289b1b3f6e10874719c27ce0a7 Mon Sep 17 00:00:00 2001
-From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
-Date: Tue, 25 Feb 2014 13:25:22 -0300
-Subject: [PATCH] UBI: R/O block driver on top of UBI volumes
-
-This commit introduces read-only block device emulation on top of UBI volumes.
-
-Given UBI takes care of wear leveling and bad block management it's possible
-to add a thin layer to enable block device access to UBI volumes.
-This allows to use a block-oriented filesystem on a flash device.
-
-The UBI block devices are meant to be used in conjunction with any
-regular, block-oriented file system (e.g. ext4), although it's primarily
-targeted at read-only file systems, such as squashfs.
-
-Block devices are created upon user request through new ioctls:
-UBI_IOCVOLATTBLK to attach and UBI_IOCVOLDETBLK to detach.
-Also, a new UBI module parameter is added 'ubi.block'. This parameter is
-needed in order to attach a block device on boot-up time, allowing to
-mount the rootfs on a ubiblock device.
-For instance, you could have these kernel parameters:
-
- ubi.mtd=5 ubi.block=0,0 root=/dev/ubiblock0_0
-
-Or, if you compile ubi as a module:
-
- $ modprobe ubi mtd=/dev/mtd5 block=/dev/ubi0_0
-
-Artem: amend commentaries and massage the patch a little bit.
-
-Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
-Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
----
- drivers/mtd/ubi/Kconfig | 15 +
- drivers/mtd/ubi/Makefile | 1 +
- drivers/mtd/ubi/block.c | 646 ++++++++++++++++++++++++++++++++++++++++++++
- drivers/mtd/ubi/build.c | 11 +
- drivers/mtd/ubi/cdev.c | 20 ++
- drivers/mtd/ubi/ubi.h | 14 +
- include/uapi/mtd/ubi-user.h | 11 +
- 7 files changed, 718 insertions(+)
- create mode 100644 drivers/mtd/ubi/block.c
-
---- a/drivers/mtd/ubi/Kconfig
-+++ b/drivers/mtd/ubi/Kconfig
-@@ -87,4 +87,19 @@ config MTD_UBI_GLUEBI
- work on top of UBI. Do not enable this unless you use legacy
- software.
-
-+config MTD_UBI_BLOCK
-+ bool "Read-only block devices on top of UBI volumes"
-+ default n
-+ help
-+ This option enables read-only UBI block devices support. UBI block
-+ devices will be layered on top of UBI volumes, which means that the
-+ UBI driver will transparently handle things like bad eraseblocks and
-+ bit-flips. You can put any block-oriented file system on top of UBI
-+ volumes in read-only mode (e.g., ext4), but it is probably most
-+ practical for read-only file systems, like squashfs.
-+
-+ When selected, this feature will be built in the UBI driver.
-+
-+ If in doubt, say "N".
-+
- endif # MTD_UBI
---- a/drivers/mtd/ubi/Makefile
-+++ b/drivers/mtd/ubi/Makefile
-@@ -3,5 +3,6 @@ obj-$(CONFIG_MTD_UBI) += ubi.o
- ubi-y += vtbl.o vmt.o upd.o build.o cdev.o kapi.o eba.o io.o wl.o attach.o
- ubi-y += misc.o debug.o
- ubi-$(CONFIG_MTD_UBI_FASTMAP) += fastmap.o
-+ubi-$(CONFIG_MTD_UBI_BLOCK) += block.o
-
- obj-$(CONFIG_MTD_UBI_GLUEBI) += gluebi.o
---- /dev/null
-+++ b/drivers/mtd/ubi/block.c
-@@ -0,0 +1,646 @@
-+/*
-+ * Copyright (c) 2014 Ezequiel Garcia
-+ * Copyright (c) 2011 Free Electrons
-+ *
-+ * Driver parameter handling strongly based on drivers/mtd/ubi/build.c
-+ * Copyright (c) International Business Machines Corp., 2006
-+ * Copyright (c) Nokia Corporation, 2007
-+ * Authors: Artem Bityutskiy, Frank Haverkamp
-+ *
-+ * 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, version 2.
-+ *
-+ * 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.
-+ */
-+
-+/*
-+ * Read-only block devices on top of UBI volumes
-+ *
-+ * A simple implementation to allow a block device to be layered on top of a
-+ * UBI volume. The implementation is provided by creating a static 1-to-1
-+ * mapping between the block device and the UBI volume.
-+ *
-+ * The addressed byte is obtained from the addressed block sector, which is
-+ * mapped linearly into the corresponding LEB:
-+ *
-+ * LEB number = addressed byte / LEB size
-+ *
-+ * This feature is compiled in the UBI core, and adds a new 'block' parameter
-+ * to allow early block device attaching. Runtime block attach/detach for UBI
-+ * volumes is provided through two new UBI ioctls: UBI_IOCVOLATTBLK and
-+ * UBI_IOCVOLDETBLK.
-+ */
-+
-+#include <linux/module.h>
-+#include <linux/init.h>
-+#include <linux/err.h>
-+#include <linux/kernel.h>
-+#include <linux/list.h>
-+#include <linux/mutex.h>
-+#include <linux/slab.h>
-+#include <linux/vmalloc.h>
-+#include <linux/mtd/ubi.h>
-+#include <linux/workqueue.h>
-+#include <linux/blkdev.h>
-+#include <linux/hdreg.h>
-+#include <asm/div64.h>
-+
-+#include "ubi-media.h"
-+#include "ubi.h"
-+
-+/* Maximum number of supported devices */
-+#define UBIBLOCK_MAX_DEVICES 32
-+
-+/* Maximum length of the 'block=' parameter */
-+#define UBIBLOCK_PARAM_LEN 63
-+
-+/* Maximum number of comma-separated items in the 'block=' parameter */
-+#define UBIBLOCK_PARAM_COUNT 2
-+
-+struct ubiblock_param {
-+ int ubi_num;
-+ int vol_id;
-+ char name[UBIBLOCK_PARAM_LEN+1];
-+};
-+
-+/* Numbers of elements set in the @ubiblock_param array */
-+static int ubiblock_devs __initdata;
-+
-+/* MTD devices specification parameters */
-+static struct ubiblock_param ubiblock_param[UBIBLOCK_MAX_DEVICES] __initdata;
-+
-+struct ubiblock {
-+ struct ubi_volume_desc *desc;
-+ int ubi_num;
-+ int vol_id;
-+ int refcnt;
-+ int leb_size;
-+
-+ struct gendisk *gd;
-+ struct request_queue *rq;
-+
-+ struct workqueue_struct *wq;
-+ struct work_struct work;
-+
-+ struct mutex dev_mutex;
-+ spinlock_t queue_lock;
-+ struct list_head list;
-+};
-+
-+/* Linked list of all ubiblock instances */
-+static LIST_HEAD(ubiblock_devices);
-+static DEFINE_MUTEX(devices_mutex);
-+static int ubiblock_major;
-+
-+static int __init ubiblock_set_param(const char *val,
-+ const struct kernel_param *kp)
-+{
-+ int i, ret;
-+ size_t len;
-+ struct ubiblock_param *param;
-+ char buf[UBIBLOCK_PARAM_LEN];
-+ char *pbuf = &buf[0];
-+ char *tokens[UBIBLOCK_PARAM_COUNT];
-+
-+ if (!val)
-+ return -EINVAL;
-+
-+ len = strnlen(val, UBIBLOCK_PARAM_LEN);
-+ if (len == 0) {
-+ ubi_warn("block: empty 'block=' parameter - ignored\n");
-+ return 0;
-+ }
-+
-+ if (len == UBIBLOCK_PARAM_LEN) {
-+ ubi_err("block: parameter \"%s\" is too long, max. is %d\n",
-+ val, UBIBLOCK_PARAM_LEN);
-+ return -EINVAL;
-+ }
-+
-+ strcpy(buf, val);
-+
-+ /* Get rid of the final newline */
-+ if (buf[len - 1] == '\n')
-+ buf[len - 1] = '\0';
-+
-+ for (i = 0; i < UBIBLOCK_PARAM_COUNT; i++)
-+ tokens[i] = strsep(&pbuf, ",");
-+
-+ param = &ubiblock_param[ubiblock_devs];
-+ if (tokens[1]) {
-+ /* Two parameters: can be 'ubi, vol_id' or 'ubi, vol_name' */
-+ ret = kstrtoint(tokens[0], 10, &param->ubi_num);
-+ if (ret < 0)
-+ return -EINVAL;
-+
-+ /* Second param can be a number or a name */
-+ ret = kstrtoint(tokens[1], 10, &param->vol_id);
-+ if (ret < 0) {
-+ param->vol_id = -1;
-+ strcpy(param->name, tokens[1]);
-+ }
-+
-+ } else {
-+ /* One parameter: must be device path */
-+ strcpy(param->name, tokens[0]);
-+ param->ubi_num = -1;
-+ param->vol_id = -1;
-+ }
-+
-+ ubiblock_devs++;
-+
-+ return 0;
-+}
-+
-+static const struct kernel_param_ops ubiblock_param_ops = {
-+ .set = ubiblock_set_param,
-+};
-+module_param_cb(block, &ubiblock_param_ops, NULL, 0);
-+MODULE_PARM_DESC(block, "Attach block devices to UBI volumes. Parameter format: block=<path|dev,num|dev,name>.\n"
-+ "Multiple \"block\" parameters may be specified.\n"
-+ "UBI volumes may be specified by their number, name, or path to the device node.\n"
-+ "Examples\n"
-+ "Using the UBI volume path:\n"
-+ "ubi.block=/dev/ubi0_0\n"
-+ "Using the UBI device, and the volume name:\n"
-+ "ubi.block=0,rootfs\n"
-+ "Using both UBI device number and UBI volume number:\n"
-+ "ubi.block=0,0\n");
-+
-+static struct ubiblock *find_dev_nolock(int ubi_num, int vol_id)
-+{
-+ struct ubiblock *dev;
-+
-+ list_for_each_entry(dev, &ubiblock_devices, list)
-+ if (dev->ubi_num == ubi_num && dev->vol_id == vol_id)
-+ return dev;
-+ return NULL;
-+}
-+
-+static int ubiblock_read_to_buf(struct ubiblock *dev, char *buffer,
-+ int leb, int offset, int len)
-+{
-+ int ret;
-+
-+ ret = ubi_read(dev->desc, leb, buffer, offset, len);
-+ if (ret) {
-+ ubi_err("%s ubi_read error %d",
-+ dev->gd->disk_name, ret);
-+ return ret;
-+ }
-+ return 0;
-+}
-+
-+static int ubiblock_read(struct ubiblock *dev, char *buffer,
-+ sector_t sec, int len)
-+{
-+ int ret, leb, offset;
-+ int bytes_left = len;
-+ int to_read = len;
-+ loff_t pos = sec << 9;
-+
-+ /* Get LEB:offset address to read from */
-+ offset = do_div(pos, dev->leb_size);
-+ leb = pos;
-+
-+ while (bytes_left) {
-+ /*
-+ * We can only read one LEB at a time. Therefore if the read
-+ * length is larger than one LEB size, we split the operation.
-+ */
-+ if (offset + to_read > dev->leb_size)
-+ to_read = dev->leb_size - offset;
-+
-+ ret = ubiblock_read_to_buf(dev, buffer, leb, offset, to_read);
-+ if (ret)
-+ return ret;
-+
-+ buffer += to_read;
-+ bytes_left -= to_read;
-+ to_read = bytes_left;
-+ leb += 1;
-+ offset = 0;
-+ }
-+ return 0;
-+}
-+
-+static int do_ubiblock_request(struct ubiblock *dev, struct request *req)
-+{
-+ int len, ret;
-+ sector_t sec;
-+
-+ if (req->cmd_type != REQ_TYPE_FS)
-+ return -EIO;
-+
-+ if (blk_rq_pos(req) + blk_rq_cur_sectors(req) >
-+ get_capacity(req->rq_disk))
-+ return -EIO;
-+
-+ if (rq_data_dir(req) != READ)
-+ return -ENOSYS; /* Write not implemented */
-+
-+ sec = blk_rq_pos(req);
-+ len = blk_rq_cur_bytes(req);
-+
-+ /*
-+ * Let's prevent the device from being removed while we're doing I/O
-+ * work. Notice that this means we serialize all the I/O operations,
-+ * but it's probably of no impact given the NAND core serializes
-+ * flash access anyway.
-+ */
-+ mutex_lock(&dev->dev_mutex);
-+ ret = ubiblock_read(dev, req->buffer, sec, len);
-+ mutex_unlock(&dev->dev_mutex);
-+
-+ return ret;
-+}
-+
-+static void ubiblock_do_work(struct work_struct *work)
-+{
-+ struct ubiblock *dev =
-+ container_of(work, struct ubiblock, work);
-+ struct request_queue *rq = dev->rq;
-+ struct request *req;
-+ int res;
-+
-+ spin_lock_irq(rq->queue_lock);
-+
-+ req = blk_fetch_request(rq);
-+ while (req) {
-+
-+ spin_unlock_irq(rq->queue_lock);
-+ res = do_ubiblock_request(dev, req);
-+ spin_lock_irq(rq->queue_lock);
-+
-+ /*
-+ * If we're done with this request,
-+ * we need to fetch a new one
-+ */
-+ if (!__blk_end_request_cur(req, res))
-+ req = blk_fetch_request(rq);
-+ }
-+
-+ spin_unlock_irq(rq->queue_lock);
-+}
-+
-+static void ubiblock_request(struct request_queue *rq)
-+{
-+ struct ubiblock *dev;
-+ struct request *req;
-+
-+ dev = rq->queuedata;
-+
-+ if (!dev)
-+ while ((req = blk_fetch_request(rq)) != NULL)
-+ __blk_end_request_all(req, -ENODEV);
-+ else
-+ queue_work(dev->wq, &dev->work);
-+}
-+
-+static int ubiblock_open(struct block_device *bdev, fmode_t mode)
-+{
-+ struct ubiblock *dev = bdev->bd_disk->private_data;
-+ int ret;
-+
-+ mutex_lock(&dev->dev_mutex);
-+ if (dev->refcnt > 0) {
-+ /*
-+ * The volume is already open, just increase the reference
-+ * counter.
-+ */
-+ goto out_done;
-+ }
-+
-+ /*
-+ * We want users to be aware they should only mount us as read-only.
-+ * It's just a paranoid check, as write requests will get rejected
-+ * in any case.
-+ */
-+ if (mode & FMODE_WRITE) {
-+ ret = -EPERM;
-+ goto out_unlock;
-+ }
-+
-+ dev->desc = ubi_open_volume(dev->ubi_num, dev->vol_id, UBI_READONLY);
-+ if (IS_ERR(dev->desc)) {
-+ ubi_err("%s failed to open ubi volume %d_%d",
-+ dev->gd->disk_name, dev->ubi_num, dev->vol_id);
-+ ret = PTR_ERR(dev->desc);
-+ dev->desc = NULL;
-+ goto out_unlock;
-+ }
-+
-+out_done:
-+ dev->refcnt++;
-+ mutex_unlock(&dev->dev_mutex);
-+ return 0;
-+
-+out_unlock:
-+ mutex_unlock(&dev->dev_mutex);
-+ return ret;
-+}
-+
-+static void ubiblock_release(struct gendisk *gd, fmode_t mode)
-+{
-+ struct ubiblock *dev = gd->private_data;
-+
-+ mutex_lock(&dev->dev_mutex);
-+ dev->refcnt--;
-+ if (dev->refcnt == 0) {
-+ ubi_close_volume(dev->desc);
-+ dev->desc = NULL;
-+ }
-+ mutex_unlock(&dev->dev_mutex);
-+}
-+
-+static int ubiblock_getgeo(struct block_device *bdev, struct hd_geometry *geo)
-+{
-+ /* Some tools might require this information */
-+ geo->heads = 1;
-+ geo->cylinders = 1;
-+ geo->sectors = get_capacity(bdev->bd_disk);
-+ geo->start = 0;
-+ return 0;
-+}
-+
-+static const struct block_device_operations ubiblock_ops = {
-+ .owner = THIS_MODULE,
-+ .open = ubiblock_open,
-+ .release = ubiblock_release,
-+ .getgeo = ubiblock_getgeo,
-+};
-+
-+int ubiblock_add(struct ubi_volume_info *vi)
-+{
-+ struct ubiblock *dev;
-+ struct gendisk *gd;
-+ int disk_capacity;
-+ int ret;
-+
-+ /* Check that the volume isn't already handled */
-+ mutex_lock(&devices_mutex);
-+ if (find_dev_nolock(vi->ubi_num, vi->vol_id)) {
-+ mutex_unlock(&devices_mutex);
-+ return -EEXIST;
-+ }
-+ mutex_unlock(&devices_mutex);
-+
-+ dev = kzalloc(sizeof(struct ubiblock), GFP_KERNEL);
-+ if (!dev)
-+ return -ENOMEM;
-+
-+ mutex_init(&dev->dev_mutex);
-+
-+ dev->ubi_num = vi->ubi_num;
-+ dev->vol_id = vi->vol_id;
-+ dev->leb_size = vi->usable_leb_size;
-+
-+ /* Initialize the gendisk of this ubiblock device */
-+ gd = alloc_disk(1);
-+ if (!gd) {
-+ ubi_err("block: alloc_disk failed");
-+ ret = -ENODEV;
-+ goto out_free_dev;
-+ }
-+
-+ gd->fops = &ubiblock_ops;
-+ gd->major = ubiblock_major;
-+ gd->first_minor = dev->ubi_num * UBI_MAX_VOLUMES + dev->vol_id;
-+ gd->private_data = dev;
-+ sprintf(gd->disk_name, "ubiblock%d_%d", dev->ubi_num, dev->vol_id);
-+ disk_capacity = (vi->size * vi->usable_leb_size) >> 9;
-+ set_capacity(gd, disk_capacity);
-+ dev->gd = gd;
-+
-+ spin_lock_init(&dev->queue_lock);
-+ dev->rq = blk_init_queue(ubiblock_request, &dev->queue_lock);
-+ if (!dev->rq) {
-+ ubi_err("block: blk_init_queue failed");
-+ ret = -ENODEV;
-+ goto out_put_disk;
-+ }
-+
-+ dev->rq->queuedata = dev;
-+ dev->gd->queue = dev->rq;
-+
-+ /*
-+ * Create one workqueue per volume (per registered block device).
-+ * Rembember workqueues are cheap, they're not threads.
-+ */
-+ dev->wq = alloc_workqueue(gd->disk_name, 0, 0);
-+ if (!dev->wq)
-+ goto out_free_queue;
-+ INIT_WORK(&dev->work, ubiblock_do_work);
-+
-+ mutex_lock(&devices_mutex);
-+ list_add_tail(&dev->list, &ubiblock_devices);
-+ mutex_unlock(&devices_mutex);
-+
-+ /* Must be the last step: anyone can call file ops from now on */
-+ add_disk(dev->gd);
-+ ubi_msg("%s created from ubi%d:%d(%s)",
-+ dev->gd->disk_name, dev->ubi_num, dev->vol_id, vi->name);
-+ return 0;
-+
-+out_free_queue:
-+ blk_cleanup_queue(dev->rq);
-+out_put_disk:
-+ put_disk(dev->gd);
-+out_free_dev:
-+ kfree(dev);
-+
-+ return ret;
-+}
-+
-+static void ubiblock_cleanup(struct ubiblock *dev)
-+{
-+ del_gendisk(dev->gd);
-+ blk_cleanup_queue(dev->rq);
-+ ubi_msg("%s released", dev->gd->disk_name);
-+ put_disk(dev->gd);
-+}
-+
-+int ubiblock_del(struct ubi_volume_info *vi)
-+{
-+ struct ubiblock *dev;
-+
-+ mutex_lock(&devices_mutex);
-+ dev = find_dev_nolock(vi->ubi_num, vi->vol_id);
-+ if (!dev) {
-+ mutex_unlock(&devices_mutex);
-+ return -ENODEV;
-+ }
-+
-+ /* Found a device, let's lock it so we can check if it's busy */
-+ mutex_lock(&dev->dev_mutex);
-+ if (dev->refcnt > 0) {
-+ mutex_unlock(&dev->dev_mutex);
-+ mutex_unlock(&devices_mutex);
-+ return -EBUSY;
-+ }
-+
-+ /* Remove from device list */
-+ list_del(&dev->list);
-+ mutex_unlock(&devices_mutex);
-+
-+ /* Flush pending work and stop this workqueue */
-+ destroy_workqueue(dev->wq);
-+
-+ ubiblock_cleanup(dev);
-+ mutex_unlock(&dev->dev_mutex);
-+ kfree(dev);
-+ return 0;
-+}
-+
-+static void ubiblock_resize(struct ubi_volume_info *vi)
-+{
-+ struct ubiblock *dev;
-+ int disk_capacity;
-+
-+ /*
-+ * Need to lock the device list until we stop using the device,
-+ * otherwise the device struct might get released in 'ubiblock_del()'.
-+ */
-+ mutex_lock(&devices_mutex);
-+ dev = find_dev_nolock(vi->ubi_num, vi->vol_id);
-+ if (!dev) {
-+ mutex_unlock(&devices_mutex);
-+ return;
-+ }
-+
-+ mutex_lock(&dev->dev_mutex);
-+ disk_capacity = (vi->size * vi->usable_leb_size) >> 9;
-+ set_capacity(dev->gd, disk_capacity);
-+ ubi_msg("%s resized to %d LEBs", dev->gd->disk_name, vi->size);
-+ mutex_unlock(&dev->dev_mutex);
-+ mutex_unlock(&devices_mutex);
-+}
-+
-+static int ubiblock_notify(struct notifier_block *nb,
-+ unsigned long notification_type, void *ns_ptr)
-+{
-+ struct ubi_notification *nt = ns_ptr;
-+
-+ switch (notification_type) {
-+ case UBI_VOLUME_ADDED:
-+ /*
-+ * We want to enforce explicit block device attaching for
-+ * volumes, so when a volume is added we do nothing.
-+ */
-+ break;
-+ case UBI_VOLUME_REMOVED:
-+ ubiblock_del(&nt->vi);
-+ break;
-+ case UBI_VOLUME_RESIZED:
-+ ubiblock_resize(&nt->vi);
-+ break;
-+ default:
-+ break;
-+ }
-+ return NOTIFY_OK;
-+}
-+
-+static struct notifier_block ubiblock_notifier = {
-+ .notifier_call = ubiblock_notify,
-+};
-+
-+static struct ubi_volume_desc * __init
-+open_volume_desc(const char *name, int ubi_num, int vol_id)
-+{
-+ if (ubi_num == -1)
-+ /* No ubi num, name must be a vol device path */
-+ return ubi_open_volume_path(name, UBI_READONLY);
-+ else if (vol_id == -1)
-+ /* No vol_id, must be vol_name */
-+ return ubi_open_volume_nm(ubi_num, name, UBI_READONLY);
-+ else
-+ return ubi_open_volume(ubi_num, vol_id, UBI_READONLY);
-+}
-+
-+static int __init ubiblock_attach_from_param(void)
-+{
-+ int i, ret;
-+ struct ubiblock_param *p;
-+ struct ubi_volume_desc *desc;
-+ struct ubi_volume_info vi;
-+
-+ for (i = 0; i < ubiblock_devs; i++) {
-+ p = &ubiblock_param[i];
-+
-+ desc = open_volume_desc(p->name, p->ubi_num, p->vol_id);
-+ if (IS_ERR(desc)) {
-+ ubi_err("block: can't open volume, err=%ld\n",
-+ PTR_ERR(desc));
-+ ret = PTR_ERR(desc);
-+ break;
-+ }
-+
-+ ubi_get_volume_info(desc, &vi);
-+ ubi_close_volume(desc);
-+
-+ ret = ubiblock_add(&vi);
-+ if (ret) {
-+ ubi_err("block: can't add '%s' volume, err=%d\n",
-+ vi.name, ret);
-+ break;
-+ }
-+ }
-+ return ret;
-+}
-+
-+static void ubiblock_detach_all(void)
-+{
-+ struct ubiblock *next;
-+ struct ubiblock *dev;
-+
-+ list_for_each_entry_safe(dev, next, &ubiblock_devices, list) {
-+ /* Flush pending work and stop workqueue */
-+ destroy_workqueue(dev->wq);
-+ /* The module is being forcefully removed */
-+ WARN_ON(dev->desc);
-+ /* Remove from device list */
-+ list_del(&dev->list);
-+ ubiblock_cleanup(dev);
-+ kfree(dev);
-+ }
-+}
-+
-+int __init ubiblock_init(void)
-+{
-+ int ret;
-+
-+ ubiblock_major = register_blkdev(0, "ubiblock");
-+ if (ubiblock_major < 0)
-+ return ubiblock_major;
-+
-+ /* Attach block devices from 'block=' module param */
-+ ret = ubiblock_attach_from_param();
-+ if (ret)
-+ goto err_detach;
-+
-+ /*
-+ * Block devices needs to be attached to volumes explicitly
-+ * upon user request. So we ignore existing volumes.
-+ */
-+ ret = ubi_register_volume_notifier(&ubiblock_notifier, 1);
-+ if (ret)
-+ goto err_unreg;
-+ return 0;
-+
-+err_unreg:
-+ unregister_blkdev(ubiblock_major, "ubiblock");
-+err_detach:
-+ ubiblock_detach_all();
-+ return ret;
-+}
-+
-+void __exit ubiblock_exit(void)
-+{
-+ ubi_unregister_volume_notifier(&ubiblock_notifier);
-+ ubiblock_detach_all();
-+ unregister_blkdev(ubiblock_major, "ubiblock");
-+}
---- a/drivers/mtd/ubi/build.c
-+++ b/drivers/mtd/ubi/build.c
-@@ -1298,6 +1298,15 @@ static int __init ubi_init(void)
- }
- }
-
-+ err = ubiblock_init();
-+ if (err) {
-+ ubi_err("block: cannot initialize, error %d", err);
-+
-+ /* See comment above re-ubi_is_module(). */
-+ if (ubi_is_module())
-+ goto out_detach;
-+ }
-+
- return 0;
-
- out_detach:
-@@ -1326,6 +1335,8 @@ static void __exit ubi_exit(void)
- {
- int i;
-
-+ ubiblock_exit();
-+
- for (i = 0; i < UBI_MAX_DEVICES; i++)
- if (ubi_devices[i]) {
- mutex_lock(&ubi_devices_mutex);
---- a/drivers/mtd/ubi/cdev.c
-+++ b/drivers/mtd/ubi/cdev.c
-@@ -561,6 +561,26 @@ static long vol_cdev_ioctl(struct file *
- break;
- }
-
-+ /* Attach a block device to an UBI volume */
-+ case UBI_IOCVOLATTBLK:
-+ {
-+ struct ubi_volume_info vi;
-+
-+ ubi_get_volume_info(desc, &vi);
-+ err = ubiblock_add(&vi);
-+ break;
-+ }
-+
-+ /* Dettach a block device from an UBI volume */
-+ case UBI_IOCVOLDETBLK:
-+ {
-+ struct ubi_volume_info vi;
-+
-+ ubi_get_volume_info(desc, &vi);
-+ err = ubiblock_del(&vi);
-+ break;
-+ }
-+
- default:
- err = -ENOTTY;
- break;
---- a/drivers/mtd/ubi/ubi.h
-+++ b/drivers/mtd/ubi/ubi.h
-@@ -864,6 +864,20 @@ int ubi_update_fastmap(struct ubi_device
- int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
- int fm_anchor);
-
-+/* block.c */
-+#ifdef CONFIG_MTD_UBI_BLOCK
-+int ubiblock_init(void);
-+void ubiblock_exit(void);
-+int ubiblock_add(struct ubi_volume_info *vi);
-+int ubiblock_del(struct ubi_volume_info *vi);
-+#else
-+static inline int ubiblock_init(void) { return 0; }
-+static inline void ubiblock_exit(void) {}
-+static inline int ubiblock_add(struct ubi_volume_info *vi) { return -ENOTTY; }
-+static inline int ubiblock_del(struct ubi_volume_info *vi) { return -ENOTTY; }
-+#endif
-+
-+
- /*
- * ubi_rb_for_each_entry - walk an RB-tree.
- * @rb: a pointer to type 'struct rb_node' to use as a loop counter
---- a/include/uapi/mtd/ubi-user.h
-+++ b/include/uapi/mtd/ubi-user.h
-@@ -134,6 +134,13 @@
- * used. A pointer to a &struct ubi_set_vol_prop_req object is expected to be
- * passed. The object describes which property should be set, and to which value
- * it should be set.
-+ *
-+ * Block devices on UBI volumes
-+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-+ *
-+ * To attach or detach a block device from an UBI volume the %UBI_IOCVOLATTBLK
-+ * and %UBI_IOCVOLDETBLK ioctl commands should be used, respectively.
-+ * These commands take no arguments.
- */
-
- /*
-@@ -191,6 +198,10 @@
- /* Set an UBI volume property */
- #define UBI_IOCSETVOLPROP _IOW(UBI_VOL_IOC_MAGIC, 6, \
- struct ubi_set_vol_prop_req)
-+/* Attach a block device to an UBI volume */
-+#define UBI_IOCVOLATTBLK _IO(UBI_VOL_IOC_MAGIC, 7)
-+/* Detach a block device from an UBI volume */
-+#define UBI_IOCVOLDETBLK _IO(UBI_VOL_IOC_MAGIC, 8)
-
- /* Maximum MTD device name length supported by UBI */
- #define MAX_UBI_MTD_NAME_LEN 127