Improve DAXFS support

Signed-off-by: Cong Wang <cwang@multikernel.io>

Author: congwang-mk

src/kerf/daxfs/__init__.py

@@ -14,9 +14,9 @@
 
 """DAXFS filesystem image creation for multikernel."""
 
-from .mkdaxfs import create_daxfs_image, DaxfsError, DaxfsImage
+from .mkdaxfs import create_daxfs_image, DaxfsError, DaxfsImage, inject_kerf_init
 
-__all__ = ["create_daxfs_image", "DaxfsError", "DaxfsImage"]
+__all__ = ["create_daxfs_image", "DaxfsError", "DaxfsImage", "inject_kerf_init"]
 
 
 

src/kerf/daxfs/mkdaxfs.py

@@ -310,6 +310,23 @@ def _allocate_dma_heap(heap_path: str, size: int) -> tuple[int, mmap.mmap]:
 
 KERF_DAXFS_MNT_DIR = "/var/lib/kerf/daxfs"
 
+KERF_INIT_TEMPLATE = """#!/bin/sh
+mount -t proc proc /proc
+mount -t sysfs sysfs /sys
+mkdir -p /dev/pts
+mount -t devpts devpts /dev/pts
+ifconfig eth0 192.168.122.157
+cat /proc/uptime > /dev/kmsg
+exec {entrypoint}
+"""
+
+
+def inject_kerf_init(rootfs_path: str, entrypoint: str) -> None:
+    """Inject /init wrapper script into rootfs."""
+    init_path = Path(rootfs_path) / "init"
+    init_path.write_text(KERF_INIT_TEMPLATE.format(entrypoint=entrypoint))
+    os.chmod(init_path, 0o755)
+
 
 def _mount_daxfs(instance_name: str, phys_addr: int, size: int) -> None:
     """