VFIO device registration fix + IOMMUFD callbacks + VFIO ioctl handlers

- Removed IOMMU group addition before vfio_register_emulated_iommu_dev() in nv_vgpu_mdev_create()
- Added IOMMUFD callbacks (bind_iommufd, unbind_iommufd, attach_ioas, detach_ioas) using kernel's vfio_iommufd_emulated_* functions
- Implemented VFIO ioctl handlers: GET_INFO, GET_REGION_INFO, GET_IRQ_INFO, SET_IRQS, MMAP
- Added config space read/write handlers at offset 0x70000000000
- Mmap handler for config space, BAR0 (emulation shadow), BAR1-5 (physical VRAM/registers)
- Interrupt handler for VFIO_DEVICE_SET_IRQS (DATA_EVENTFD, DATA_NONE, DATA_BOOL)
- Added udev rules for vfio group permissions
- Created stack_manager.sh unified tool
- Fixed mdev remove crash with deferred cleanup in vfio_device_release callback
- Kernel 6.8+ IOMMUFD compatibility
- QEMU launches successfully with vGPU passthrough

1 files changed, 75 insertions, 0 deletions

diff --git a/docs/tools/README.md b/docs/tools/README.md
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+# Open-IOV Tools Documentation
+
+## Overview
+This directory contains documentation for userspace tools built on top of the Open-IOV vGPU-IO stack, leveraging recycled NVIDIA RM API code from `integ/gpu_drv/ext-tree/`.
+
+## Tools
+
+### Debugging & Observability (Implemented)
+| Tool | Location | Description |
+|------|----------|-------------|
+| `guest_init_monitor.py` | `tools/` | Correlates host dmesg with guest serial output |
+| `failure_analyzer.py` | `tools/` | Classifies guest init failures with recommendations |
+| `benchmark_infrastructure.sh` | `tools/` | VM vs bare metal benchmark runner |
+| `guest_test_agent.py` | `tools/guest_agent/` | Guest-side test agent (vsock/TCP) |
+| `debug_guest_init.sh` | `scripts/` | One-command debug launch (QEMU + GDB + monitor) |
+| `windows_guest_automation.sh` | `scripts/` | Windows guest automation via WinRM |
+
+### RM API Tooling (Planned)
+| Tool | Documentation | Description |
+|------|---------------|-------------|
+| `rmtool` | [rmtool.md](rmtool.md) | RM API Swiss Army Knife - CLI for state enumeration, engine control, memory ops, NV2080 direct control |
+| `rmtop` | [rmtop.md](rmtop.md) | GPU htop equivalent - ncurses real-time dashboard |
+
+## Code Reuse Sources
+All planned tools recycle existing NVIDIA driver code from `integ/gpu_drv/ext-tree/`:
+
+| Component | Path | Use Case |
+|-----------|------|----------|
+| nvidia-smi | `drivers/gpgpu/nvidia-smi/` | CLI framework, GPU enumeration, NV2080 ioctls |
+| gpumon/perfmon | `drivers/gpgpu/gpumon_perfmon/` | Performance sampling, perfmon counters |
+| NV2080 controls | `drivers/gpgpu/nv2080/` | RM control interfaces (classes, methods, events) |
+| Resource Server | `drivers/gpgpu/resserve/` | Resource Server (resserve) API |
+| CUDA Internal | `drivers/gpgpu/cudasw/` | CUDASW / CUDA Internal Layer |
+| Resource Manager | `drivers/gpgpu/resman/` | Resman API |
+
+## Build Integration
+Tools will be built under `open-iov/tools/`:
+```
+tools/
+├── rmtool/
+│   ├── src/
+│   ├── lib/
+│   └── Makefile
+├── rmtop/
+│   ├── src/
+│   ├── lib/
+│   └── Makefile
+└── Makefile          # Builds all tools
+```
+
+## Dependencies
+- `libnvidia-rmapi.so` - Recycled RM API (from ext-tree)
+- `libgpumon.so` - Recycled perfmon (from ext-tree)
+- `libpciaccess` - PCI configuration access
+- `libnuma` - NUMA topology
+- `ncursesw` - rmtop UI (wide character support)
+- `libjson-c` - JSON output formatting
+- `libcurl` - Remote API (future)
+
+## Integration with Open-IOV Stack
+Tools will integrate with the host VFIO driver via:
+- `/dev/nvidia*` character devices (existing nvidia.ko)
+- `open-iov-vfio.ko` debugfs interface (`/sys/kernel/debug/open-iov-vfio/`)
+- VFIO ioctls for guest state introspection
+- GSP-RM telemetry via firmware analyzer / dynamic dispatcher
+
+## Future Tool Ideas
+| Tool | Purpose |
+|------|---------|
+| `rmmigrate` | Live migration coordinator via resserve |
+| `rmprofile` | Workload profiler (CUDA/Video/AI correlation) |
+| `rmpolicy` | Policy engine for automated engine allocation |
+| `rmtelemetry` | Telemetry exporter (Prometheus/OTel/InfluxDB) |
+| `rmguest` | Guest introspection via vGPU VFIO interface |
+| `rmfirmware` | GSP firmware analysis / update utility |
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