Configuring a Native Build

With environment variables set up as described in Building a Hosted Inferno Environment, we can configure a native build.

In principle, each of the platforms that can run Inferno natively is represented by a subdirectory of the inferno-os/os directory. Using the tools that were built when we created the hosted environment, it should be possible to build a kernel for each of these platforms.

Initially, we will build a native kernel for a 32-bit x86-based PC.

Enter the port directory

For the native PC build, the directory containing much of the code specific to the platform is inferno-os/os/pc. From the root of the source distribution, enter this directory:

#!bash

cd os/pc

For some reason the configuration file contains references to directories that do not exist in the standard inferno-os source directory. Copy the fix-pc-build.py script into the current directory and run it:

#!bash

python fix-pc-build.py pc

This modifies the pc configuration file, enabling the shell by default and adding a couple of missing files. It should now be possible to build the kernel:

#!bash

mk

If successful, the end result should be a file called ipc in the current directory. This needs to be compressed, and we also need to create a file that will tell the bootloader where to find it:

#!bash

gzip -9 ipc
echo 'bootfile=fd0!ipc.gz' > plan9.ini

Some additional components are required to boot the kernel. We build these by entering the inferno-os/os/boot/pc directory and running the mk tool:

#!bash

cd $INFERNO_ROOT/os/boot/pc/
mk pbs.install 9load.install

With these in place, the last thing to do is to construct a bootable image containing the boot block, bootloader and kernel. We use the hosted environment to do this:

#!bash

emu

In the hosted environment, execute the following commands to enter the directory containing the PC version and create a disk image called disk:

cd os/pc
disk/format -b /Inferno/386/pbs -df disk /Inferno/386/9load plan9.ini ipc.gz
exit

The disk image can be tested using qemu:

#!bash

qemu -m 512M -fda $INFERNO_ROOT/os/pc/disk

This should boot to a shell prompt.

References

This information is based on How to Build a Native Inferno Kernel for the PC by Brian Stuart.