转：http://www.armadeus.com/wiki/index.php?title=UBIFS
This is a preliminary page dealing with the installation of UBIFS on the APF boards. UBIFS will replace JFFS2 file system on NAND (and NOR as well) based boards because JFFS2 induces a big overhead when parsing, reading and writing large devices, see UBIFS scalability.
Introduction
Host Setup
- add uuid-dev packages (should be already installed as required to build the HEAD of Armadeus repository):
$ sudo apt-get install uuid-dev
APF build config
Buildroot
$ make menuconfig
APF51:
Target filesystem options --->
[*] ubifs root filesystem
(0x1f800) UBI logical erase block size
(0x800) UBI minimum I/O size
(2047) Maximum LEB count
ubifs runtime compression (lzo) --->
Compression method (no compression) --->
[*] UBI image
(0x20000) UBI physical erase block size
(512) UBI sub-page size
APF27:
Target filesystem options --->
[*] ubifs root filesystem
(0x20000) UBI physical erase block size
(0x1f800) UBI logical erase block size
(0x800) UBI minimum I/O size
(512) UBI sub-page size
(2047) Maximum LEB count
$ make
Linux
$ make linux-menuconfig
File systems --->
[*] Miscellaneous filesystems --->
<*> UBIFS file system support and disable debugging !!
Device Drivers --->
<*> Memory Technology Device (MTD) support --->
UBI - Unsorted block images --->
<*> Enable UBI
(4096) UBI wear-leveling threshold and disable debugging !!
$ make linux
- reflash your kernel
U-Boot envt variables
BIOS> setenv bootcmd run ubifsboot
BIOS> setenv download_rootfs tftpboot ${loadaddr} ${serverpath}${board_name}-rootfs.arm.ubi
Additional informations
A new file 'ubinize.cfg' defining the ubi volumes is located in buildroot/target/ubifs/. This file contains the different UBI volumes of the UBI image:
[ubifs]
mode=ubi
vol_id=0
vol_type=dynamic
vol_name=rootfs
vol_alignment=1
vol_flags=autoresize
This file is processed by the ubinize utility after mkfs.ubifs.
U-Boot access to UBIFS partitions
U-Boot can read files from the rootfs / UBIFS partition using the commands: uni, ubifsmount, ubifsls, ubifsload. Here is an example applicable to the apf27, apf28 and apf51 boards:
BIOS> ubi part rootfs
UBI: attaching mtd1 to ubi0
UBI: physical eraseblock size: 131072 bytes (128 KiB)
UBI: logical eraseblock size: 129024 bytes
UBI: smallest flash I/O unit: 2048
UBI: sub-page size: 512
UBI: VID header offset: 512 (aligned 512)
UBI: data offset: 2048
UBI: attached mtd1 to ubi0
UBI: MTD device name: "mtd=7"
UBI: MTD device size: 500 MiB
UBI: number of good PEBs: 3988
UBI: number of bad PEBs: 12
UBI: max. allowed volumes: 128
UBI: wear-leveling threshold: 4096
UBI: number of internal volumes: 1
UBI: number of user volumes: 1
UBI: available PEBs: 0
UBI: total number of reserved PEBs: 3988
UBI: number of PEBs reserved for bad PEB handling: 39
UBI: max/mean erase counter: 2/0
BIOS> ubifsmount ubi0:rootfs
UBIFS: mounted UBI device 0, volume 0, name "rootfs"
UBIFS: mounted read-only
UBIFS: file system size: 504483840 bytes (492660 KiB, 481 MiB, 3910 LEBs)
UBIFS: journal size: 9033728 bytes (8822 KiB, 8 MiB, 71 LEBs)
UBIFS: media format: w4/r0 (latest is w4/r0)
UBIFS: default compressor: LZO
UBIFS: reserved for root: 0 bytes (0 KiB)
BIOS> ubifsls /boot
2604048 Thu Oct 03 08:38:56 2013 apf51-linux.bin
BIOS> ubifsload 90000000 /boot/apf51-linux.bin
Loading file '/boot/apf51-linux.bin' to addr 0x90000000 with size 2604048 (0x0027bc10)...
Done
Acces to UBIFS files from U-Boot can used to do an update of your system after deployement on site through some U-Boot scripts..