This example shows how to embed a new file system into the virtual file system (VFS) that is provided in KasperskyOS Community Edition.
In this example, the Client program tests the operation of file systems (ext2, ext3, ext4) on block devices. To do so, the Client queries the virtual file system (the FileVfs program) via IPC, and FileVfs in turn queries the block device via IPC.
The ext2 and ext3 file systems work with the default settings. The ext4 file system works if you disable extent (mkfs.ext4 -O ^64bit,^extent /dev/foo).
Example files
The code of the example and build scripts are available at the following path:
/opt/KasperskyOS-Community-Edition-<version>/examples/embed_ext2_with_separate_vfs
Building and running example
To run an example on QEMU, go to the directory containing the example, build the example and run the following commands:
$ cd build/einit
# Before running the following command, be sure that the path to
# the directory with the qemu-system-aarch64 executable file is saved in
# the PATH environment variable. If it is not there,
# add it to the PATH variable.
$ qemu-system-aarch64 -m 2048 -machine vexpress-a15 -nographic -monitor none -sd hdd.img -kernel kos-qemu-image
See also Building and running examples section.
Preparing an SD card to run on Raspberry Pi 4 B
To run the embed_ext2_with_separate_vfs example on Raspberry Pi 4 B, the SD card needs to have both a bootable partition with the solution image as well as 3 additional partitions with the ext2, ext3 and ext4 file systems, respectively.