diff options
| -rw-r--r-- | include/mtd/ubi-user.h | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h index 296efae..4b139a6 100644 --- a/include/mtd/ubi-user.h +++ b/include/mtd/ubi-user.h @@ -25,11 +25,12 @@ * UBI device creation (the same as MTD device attachment) * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * - * MTD devices may be attached using %UBI_IOCATT ioctl command of the UBI - * control device. The caller has to properly fill and pass - * &struct ubi_attach_req object - UBI will attach the MTD device specified in - * the request and return the newly created UBI device number as the ioctl - * return value. + * MTD and block devices may be attached using %UBI_IOCATT ioctl command of the + * UBI control device. The caller has to properly fill and pass + * &struct ubi_attach_req object. If the @bdev_major and @bdev_minor fields + * contain zeroes, UBI will attaches MTD device number @mtd_num. Otherwise it + * attaches block device with major/minor numbers @bdev_major and @bdev_minor. + * The ioctl returns the newly created UBI device number. * * UBI device deletion (the same as MTD device detachment) * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -235,14 +236,25 @@ enum { * @ubi_num: UBI device number to create * @mtd_num: MTD device number to attach * @vid_hdr_offset: VID header offset (use defaults if %0) + * @bdev_major: major number of the block device to attach + * @bdev_minor: minor number of the block device to attach * @padding: reserved for future, not used, has to be zeroed * - * This data structure is used to specify MTD device UBI has to attach and the + * This data structure is used to specify the device UBI has to attach and the * parameters it has to use. The number which should be assigned to the new UBI * device is passed in @ubi_num. UBI may automatically assign the number if * @UBI_DEV_NUM_AUTO is passed. In this case, the device number is returned in * @ubi_num. * + * UBI can attach block and MTD devices. To attach a block device, @bdev_major + * and @bdev_minor have to contain block device major an minor numbers. And + * @mtd_num and @vid_hdr_offset have to contain zeroes. Note, the major number + * cannot be zero. To attach an MTD device, @bdev_major and @bdev_minor have to + * contain zeroes, while @mtd_num has to contain the MTD device number to + * attach. + * + * The rest of the documentation is specific to the MTD device case. + * * Most applications should pass %0 in @vid_hdr_offset to make UBI use default * offset of the VID header within physical eraseblocks. The default offset is * the next min. I/O unit after the EC header. For example, it will be offset @@ -263,7 +275,9 @@ struct ubi_attach_req { int32_t ubi_num; int32_t mtd_num; int32_t vid_hdr_offset; - int8_t padding[12]; + int32_t bdev_major; + int32_t bdev_minor; + int8_t padding[4]; }; /** |