From: Ezequiel Garcia Date: Tue, 25 Feb 2014 16:25:22 +0000 (-0300) Subject: UBI: R/O block driver on top of UBI volumes X-Git-Tag: v3.15-rc1~93^2~8 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9d54c8a33eec78289b1b3f6e10874719c27ce0a7;p=pandora-kernel.git 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 Signed-off-by: Artem Bityutskiy --- Reading git-diff-tree failed