I went back and forth about the file system and disk stuff a fair bunch, to be honest. Most of it, as you say, was mostly due to wrestling the space constraints.
If one day I'll give in and take the shell out or go multi-stage, I will definitely look at that.
Maybe it's worth blogging about the journey; it's been a few weeks of merciless trade-offs to reach a usable API. It can make for a fun read (:
haha, well all the best! its a cool project. i am happy i can forgot about BIOS and went UEFI haha. remember so many tedious nights trying to get an mbr to load an elf file and init x64 mode in one go :'). uefi (edk2) is a blessing if you come from BIOS land (tho mybe less fun in a way!)
the BIOS will recognize block devices as being of certain type and present them to controllers.
if you do not put partition table, qemu AHCI controller will not recognize disk as bootable and u cant use SATA. with only the magic footer at the end of mbr, it will only work on IDE controller.
the BIOS will recognize block devices as being of certain type and present them to controllers.
What exactly do you mean by that? Device discovery proceeds from the root (usually PCIe bus, after CPU-specific init) to the leaves, not the other way around.
qemu AHCI controller
That's its problem then. This isn't a problem on real hardware.
if you want an ahci controller to 'see' it, it will need partition table too, which will make it even less bytes (or maybe cleverly encoded)