Linux File System migration-JFFS2 file system creation

Linux File System transplantation-JFFS2 File System JFFS2 full name is Journalling Flash File System Version2, is a Flash Memory developed by Redhat (short: Flash Memory; English: Flash Memory) file System [1], its predecessor is JFFS, which only supports NOR Flash at the earliest. It has been supporting NAND Flash since version 2.6 and is very suitable for embedded systems.
JFFS2 features: supports NAND flash devices. Hard links ). This is a feature that JFFS cannot support due to file formats. Compression. Three algorithms are available: zlib, rubin, and rtime. For better performance.
Disadvantage: JFFS2 scans all the data in flash during mounting and stores the directory of the file system in system memory, which leads to linear growth and consumes a lot of time. JFFS2 does not have a write-back mechanism and cannot store data in cache, so that flash I/O operations are frequent. The JFFS2 design mechanism is too complex and the code is not easy to read.
I. Transplantation environment: www.2cto.com 1, Ubuntu 10.10 release version 2, u-boot.bin http://download.csdn.net/detail/baby_afu/44128263, target machine: FS_S5PC100 Platform 4, cross compiler arm-cortex_a8-linux-gnueabi-gcc Article 2, the production of jffs2 File system 1, configure the Kernel support jffs2 File system $ make menuconfig File system ---> [*] Miscellaneous filesystems ---> <*> Journalling flash File System v2 (JFFS2) support 2, zlib compilation decompression zlib-1 .2.3.tar.bz2 http://download.csdn.net/detail/baby_afu/4418294 and enter the zlib-1.2.3 configuration to compile and install $ tar xvf zlib-1.2.3.tar.bz2 $ cd zlib-1.2.3 www.2cto.com $. /configure $ make install 3. mtd tool compilation decompress mtd-snapshot-20050519.tar.bz2 unzip $ tar xvf mtd-snapshot-20050519.tar.bz2 $ cd mtd/util $ make install so that our system has mkfs. jffs2 tool 4. jffs2 file system image creation $ mkfs. Jffs2-r/source/rootfs-o rootfs. jffs2-e 0x4000 -- pad = 0x800000-n $ cp rootfs. jffs2/tftpboot www.2cto.com 5, jffs2 File System burning write # tftp 30008000 rootfs. jffs2 # nand erase 500000 800000 # nand write 30008000 500000 800000 6. Set the u-boot startup parameter # setenv bootcmd tftp 33000000 zImage \; go 33000000 # setenv bootargs root =/dev/mtdblock2 init =/linuxrc rootfstype = jffs2 rw console = ttySAC0, 115200 # savenv restart the Development Board to check whether it is successful. Author lr_ting