mkfs.ubifs 製作UBIFS 鏡像
mkfs.ubifs的用法
Usage: mkfs.ubifs [OPTIONS] target
Make a UBIFS file system image from an existing directory tree
Examples:
Build file system from directory /opt/img, writting the result in the ubifs.img file
mkfs.ubifs -m 512 -e 128KiB -c 100 -r /opt/img ubifs.img
The same, but writting directly to an UBI volume
mkfs.ubifs -r /opt/img /dev/ubi0_0
Creating an empty UBIFS filesystem on an UBI volume
mkfs.ubifs /dev/ubi0_0
Options:
-r, -d, --root=DIR build file system from directory DIR
-m, --min-io-size=SIZE minimum I/O unit size，最小輸入輸出大小
-e, --leb-size=SIZE logical erase block size邏輯可擦出塊大小
-c, --max-leb-cnt=COUNT maximum logical erase block count最大邏輯可擦出塊數目
-o, --output=FILE output to FILE輸出文件名
-j, --jrn-size=SIZE journal size
-R, --reserved=SIZE how much space should be reserved for the super-user
-x, --compr=TYPE compression type - "lzo", "favor_lzo", "zlib" or "none" (default: "lzo")
-X, --favor-percent may only be used with favor LZO compression and defines
how many percent better zlib should compress to make
mkfs.ubifs use zlib instead of LZO (default 20%)
-f, --fanout=NUM fanout NUM (default: 8)
-F, --space-fixup file-system free space has to be fixed up on first moun
(requires kernel version 3.0 or greater)
-k, --keyhash=TYPE key hash type - "r5" or "test" (default: "r5")
-p, --orph-lebs=COUNT count of erase blocks for orphans (default: 1)
-D, --devtable=FILE use device table FILE
-U, --squash-uids squash owners making all files owned by root
-l, --log-lebs=COUNT count of erase blocks for the log (used only for debugging)
-v, --verbose verbose operation
-V, --version display version information
-g, --debug=LEVEL display debug information (0 - none, 1 - statistics, 2 - files, 3 - more details)
-h, --help display this help text
例：
mkfs.ubifs -x lzo -m 2KiB -e 124KiB -c 720 -o system_ubifs.img -d $path_to_system
壓縮格式爲lzo
-m最小輸入輸出大小爲2KiB(2048bytes)，一般爲頁大小
-e邏輯可擦除塊大小爲124KiB=(每塊的頁數-2)*頁大小=（64-2）*2KiB=124KiB
-c最多邏輯可擦除塊數目爲720(720*128KiB=90MiB),這個可根據ubi volume來設置，實際上是設置此卷的最大容量。
ubinize命令可將使用mkfs.ubifs命令製作的UBIFS文件系統鏡像轉換成可直接在FLASH上燒寫的格式（帶有UBI文件系統鏡像卷標）：
ubinize -o ubi.img-m 2048 -p 128KiB-s 512 -O 2048 ubinize.cfg
ubinize.cfg爲一些配置參數：
[ubifs]
mode=ubi
image=ubifs.img
vol_id=0
vol_size=100MiB
vol_type=dynamic
vol_alignment=1
vol_name=rootfs
vol_flags=autoresize
通過此命令生成的ubi.img可直接使用NAND FLASH的燒寫命令燒寫到FLASH上。
原文鏈接：https://blog.csdn.net/yexiangcsdn/article/details/81198757