3d5fb4c267
Build system changes: - scripts/gen_initrd.sh packs all files from apps/ into a newc-format CPIO archive at build/isodir/boot/initrd.cpio. - CMakeLists.txt adds 'initrd' target as ISO dependency. GRUB loads the archive as a Multiboot2 module via 'module2 /boot/initrd.cpio'. - apps/README added as placeholder file for initial ramdisk content. Kernel changes: - kernel.c scans Multiboot2 tags for MULTIBOOT_TAG_TYPE_MODULE to find the initrd's physical address range, then passes it to cpio_init(). - cpio.c/h implements a parser for the SVR4/newc CPIO format: - cpio_init(): lists archive contents on startup - cpio_find(): look up a file by name (handles ./ prefix) - cpio_next(): iterate through all entries - cpio_count(): count files in archive - The initrd lives in identity-mapped physical memory, so no additional mapping is needed to access it. Verified in QEMU: GRUB loads the module at 0x0014A000, CPIO parser finds the README file (38 bytes). All existing functionality (Ring 3 processes, syscalls) continues to work.
15 lines
342 B
Bash
Executable File
15 lines
342 B
Bash
Executable File
#!/bin/sh
|
|
# Generate CPIO initial ramdisk from apps directory
|
|
# Usage: gen_initrd.sh <apps_dir> <output_file>
|
|
set -e
|
|
|
|
APPS_DIR="$1"
|
|
OUTPUT="$2"
|
|
|
|
# Ensure output directory exists
|
|
mkdir -p "$(dirname "$OUTPUT")"
|
|
|
|
cd "$APPS_DIR"
|
|
find . -not -name '.' | cpio -o -H newc > "$OUTPUT" 2>/dev/null
|
|
echo "Generated initrd: $(wc -c < "$OUTPUT") bytes"
|