#!/bin/bash
# SPDX-License-Identifier: BSD-3-Clause
# Copyright (c) 2026 Open-IOV contributors
# Build NVIDIA OpenRM kernel modules with Open-IOV vGPU VFIO symbols
# This script ensures KBUILD_EXTRA_SYMBOLS is correctly passed to the build

set -e

OPEN_IOV_ROOT="${OPEN_IOV_ROOT:-$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)}"
NVIDIA_OPENRM_DIR="$OPEN_IOV_ROOT/nvidia-open-gpu-kernel-modules"
KERNEL_DIR="$OPEN_IOV_ROOT/kernel"
SYMVERS_FILE="$KERNEL_DIR/Module.symvers"

echo "=== Building NVIDIA OpenRM with Open-IOV vGPU VFIO symbols ==="
echo "Open-IOV root: $OPEN_IOV_ROOT"
echo "NVIDIA OpenRM dir: $NVIDIA_OPENRM_DIR"
echo "Kernel Module.symvers: $SYMVERS_FILE"

# Check if vgsp.ko has been built (provides Module.symvers)
if [ ! -f "$SYMVERS_FILE" ]; then
    echo "ERROR: $SYMVERS_FILE not found!"
    echo "Please build vgsp.ko first: cd $OPEN_IOV_ROOT && make kernel"
    exit 1
fi

echo "Found Module.symvers with $(wc -l < "$SYMVERS_FILE") exported symbols"
echo "Key vGPU symbols:"
grep -i vgpu "$SYMVERS_FILE" | head -5

# Build NVIDIA OpenRM kernel modules
cd "$NVIDIA_OPENRM_DIR/kernel-open"

# Clean previous build to ensure fresh symbol resolution
echo "Cleaning previous build..."
make clean

echo "Building NVIDIA OpenRM modules with KBUILD_EXTRA_SYMBOLS..."
KBUILD_EXTRA_SYMBOLS="$SYMVERS_FILE" make -j$(nproc) modules

# Verify the symbols are resolved
echo ""
echo "=== Verification ==="
echo "Checking nvidia.ko for vGPU VFIO symbols..."
if modinfo nvidia.ko 2>/dev/null | grep -q "nvidia_vgpu_vfio"; then
    echo "✓ nvidia.ko has vGPU VFIO symbols"
else
    echo "⚠ nvidia.ko may not have vGPU VFIO symbols (check modpost output above)"
fi

echo ""
echo "Checking Module.symvers for vGPU symbols..."
grep -i vgpu Module.symvers | head -5

echo ""
echo "=== Build Complete ==="
echo "nvidia.ko location: $NVIDIA_OPENRM_DIR/kernel-open/nvidia.ko"
echo ""
echo "To load the stack:"
echo "  sudo insmod $NVIDIA_OPENRM_DIR/kernel-open/nvidia.ko"
echo "  sudo insmod $KERNEL_DIR/vgsp.ko"
echo "  sudo cp $OPEN_IOV_ROOT/firmware/57X-GSP/570.144/gsp-570.144.fwimage.bin /lib/firmware/"
echo "  ./scripts/create_mdev.sh"
echo "  ./scripts/launch_qemu_vgpu.sh"