When building the name for the workqueue thread, make sure a format
string cannot leak in from the disk name.
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

You cannot mark these parameters as __initdata.
Otherwise the data is gone upon module exit.

Fixes:
[  172.045465] BUG: unable to handle kernel paging request at ffffffffa001db38
[  172.046020] IP: [<ffffffff81067aa4>] destroy_params+0x24/0x50
Signed-off-by: NRichard Weinberger <richard@nod.at>
Acked-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Rename the UBI_IOCVOLATTBLK and UBI_IOCVOLDETBLK to UBI_IOCVOLCRBLK and
UBI_IOCVOLRMBLK, because we do not use terms "attach" and "detach" for the R/O
block devices on top of UBI volumes. Instead, we use terms "create" and
"remove". This patch also amends the related commentaries.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>

Fixes the following warning on ARCH=avr32:

  drivers/mtd/ubi/block.c: In function 'ubiblock_read':
  drivers/mtd/ubi/block.c:207: warning: comparison of distinct pointer types lacks a cast
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

ubiblock_param_ops should be marked as __init as it's only used to set
a driver parameter on insertion time. This commit fixes the following:

  WARNING: drivers/mtd/built-in.o(.text+0x653ac): Section mismatch in
  reference from the variable ubiblock_param_ops to the function
  .init.text:ubiblock_set_param()

  The function ubiblock_param_ops() references the function __init
  ubiblock_set_param(). This is often because ubiblock_param_ops lacks a
  __init annotation or the annotation of ubiblock_set_param is wrong.

Given gcc errors if the struct is marked const __initdata, this commit
drops the const mark from it.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

We already use term attach/detach for UBI->MTD relations, let's not use this
for UBI->ubiblock relations to avoid confusion. Just use 'create' and 'remove'
instead. E.g., "create a R/O block device on top of a UBI volume".
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

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: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>