FlashFilesystemsJFFS < DULG

%SECTION0{name=FlashFilesystemJffs}% Journalling Flash File System

At the moment it seems that the Journalling Flash File System *JFFS*
is the best choice for filesystems in flash memory of embedded
devices. You must enable the following configuration options to get
JFFS support in your system:

<verbatim>
CONFIG_JFFS_FS=y
CONFIG_JFFS_FS_VERBOSE=0
</verbatim>

If the flash device is erased, we can simply mount it, and the
creation of the JFFS filesystem is performed automagically.

%T% Note: For simple accesses like direct read or write operations or
erasing you use the _character_ device interface (_/dev/mtd<NOP>*_) of
the MTD layer, while for filesystem operations like mounting we must
use the _block_ device interface (_/dev/mtdblock<NOP>*_).

<verbatim>
# eraseall /dev/mtd2
Erased 4096 Kibyte @ 0 -- 100% complete.       
# mount -t jffs /dev/mtdblock2 /mnt
# mount
/dev/root on / type nfs (rw,v2,rsize=4096,wsize=4096,hard,udp,nolock,addr=10.0.0.2)
proc on /proc type proc (rw)
devpts on /dev/pts type devpts (rw)
/dev/mtdblock2 on /mnt type jffs (rw)
# df
Filesystem           1k-blocks      Used Available Use% Mounted on
/dev/root              2087212   1232060    855152  60% /
/dev/mtdblock2            3584         0      3584   0% /mnt
</verbatim>

Now you can access the files in the JFFS filesystem in the
_/mnt_ directory.
9.1.1. Memory Technology Devices		1. Abstract		9.1.3. Second Version of JFFS
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