diff options
Diffstat (limited to 'target/linux/generic/patches-3.10/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch')
| -rw-r--r-- | target/linux/generic/patches-3.10/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch | 847 |
1 files changed, 847 insertions, 0 deletions
diff --git a/target/linux/generic/patches-3.10/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch b/target/linux/generic/patches-3.10/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch new file mode 100644 index 0000000000..50e9e2fd86 --- /dev/null +++ b/target/linux/generic/patches-3.10/040-UBI-R-O-block-driver-on-top-of-UBI-volumes.patch @@ -0,0 +1,847 @@ +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 + +diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig +index 36663af..783fb18 100644 +--- 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 +diff --git a/drivers/mtd/ubi/Makefile b/drivers/mtd/ubi/Makefile +index b46b0c97..4e3c3d7 100644 +--- 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 +diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c +new file mode 100644 +index 0000000..cea7d1c +--- /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, ¶m->ubi_num); ++ if (ret < 0) ++ return -EINVAL; ++ ++ /* Second param can be a number or a name */ ++ ret = kstrtoint(tokens[1], 10, ¶m->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"); ++} +diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c +index 57deae9..6e30a3c 100644 +--- 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); +diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c +index 8ca49f2..39d3774 100644 +--- a/drivers/mtd/ubi/cdev.c ++++ b/drivers/mtd/ubi/cdev.c +@@ -561,6 +561,26 @@ static long vol_cdev_ioctl(struct file *file, unsigned int cmd, + 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; +diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h +index 8ea6297..e76ff98 100644 +--- a/drivers/mtd/ubi/ubi.h ++++ b/drivers/mtd/ubi/ubi.h +@@ -864,6 +864,20 @@ int ubi_update_fastmap(struct ubi_device *ubi); + 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 +diff --git a/include/uapi/mtd/ubi-user.h b/include/uapi/mtd/ubi-user.h +index 723c324..b98585a 100644 +--- 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 +-- +1.9.2 + |