Create a user-space diskpart utility that can view and modify MBR
partition tables on block devices accessible through /dev.
Features:
- list: displays all 4 partition slots with type, LBA start, size
- create <slot> <type> <start> <sectors>: creates a new partition
- delete <slot>: removes a partition entry
- activate/deactivate <slot>: sets or clears the bootable flag
The tool reads sector 0 (MBR) via VFS open/read, modifies the
partition table in memory, then writes it back via open/write.
Supports hex type codes and provides human-readable type names
for common partition types (FAT12/16/32, Linux, NTFS, etc.).
Usage: diskpart hdd1 create 1 0C 2048 14336
diskpart hdd1 list
diskpart hdd1 delete 2
Add Intel 82077AA-compatible floppy disk controller driver with:
- CMOS-based drive detection (register 0x10)
- FDC reset with DOR toggle and SPECIFY command
- Motor control with spin-up delay
- ISA DMA channel 2 setup for data transfers
- LBA-to-CHS conversion for 1.44MB geometry
- Single-sector read/write via DMA with 7-byte result phase
- Seek and recalibrate with sense interrupt verification
- IRQ 6 handler (vector 38) for command completion
- Devicefs integration as 'floppy' class block devices
The IRQ wait function detects whether interrupts are enabled
(EFLAGS IF bit) and temporarily enables them if needed, allowing
the driver to work during early init before the kernel calls STI.
The scheduler safely handles timer interrupts in this window since
no user processes exist yet.
Tested with QEMU: drive detected as 1.44M 3.5", registered as
/dev/floppy1, full boot succeeds with CD+HDD+floppy attached.
