/* Virtual Function IO wrapper around kernel API.
 *
 * Author: Niklas Eiling <niklas.eiling@eonerc.rwth-aachen.de>
 * Author: Steffen Vogel <post@steffenvogel.de>
 * Author: Daniel Krebs <github@daniel-krebs.net>
 * SPDX-FileCopyrightText: 2022-2023 Niklas Eiling <niklas.eiling@eonerc.rwth-aachen.de>
 * SPDX-FileCopyrightText: 2014-2023 Steffen Vogel <post@steffenvogel.de>
 * SPDX-FileCopyrightText: 2018 Daniel Krebs <github@daniel-krebs.net>
 * SPDX-License-Identifier: Apache-2.0
 */

#pragma once

#include <list>
#include <memory>
#include <vector>

#include <linux/vfio.h>
#include <sys/mman.h>

#include <villas/kernel/vfio_group.hpp>

namespace villas {
namespace kernel {
namespace vfio {

// Backwards compatability with older kernels
#ifdef VFIO_UPDATE_VADDR
static constexpr size_t EXTENSION_SIZE = VFIO_UPDATE_VADDR + 1;
#elif defined(VFIO_UNMAP_ALL)
static constexpr size_t EXTENSION_SIZE = VFIO_UNMAP_ALL + 1;
#else
static constexpr size_t EXTENSION_SIZE = VFIO_NOIOMMU_IOMMU + 1;
#endif

class Container {
public:
  Container(std::vector<std::string> required_modules = {"vfio"});

  // No copying allowed because we manage the vfio state in constructor and destructors
  Container(Container const &) = delete;
  void operator=(Container const &) = delete;

  ~Container();

  void dump();

  void attachGroup(std::shared_ptr<Group> group);
  std::shared_ptr<Group> getOrAttachGroup(int index);

  std::shared_ptr<Device> attachDevice(const std::string &name, int groupIndex);
  std::shared_ptr<Device> attachDevice(devices::PciDevice &pdev);

  // Map VM to an IOVA, which is accessible by devices in the container
  //
  // @param virt		virtual address of memory
  // @param phys		IOVA where to map @p virt, -1 to use VFIO internal allocator
  // @param length	size of memory region in bytes
  // @return		IOVA address, UINTPTR_MAX on failure
  uintptr_t memoryMap(uintptr_t virt, uintptr_t phys, size_t length);

  // munmap() a region which has been mapped by vfio_map_region()
  bool memoryUnmap(uintptr_t phys, size_t length);

  bool isIommuEnabled() const { return this->hasIommu; }

private:
  int fd;
  int version;

  std::array<bool, EXTENSION_SIZE> extensions;
  uint64_t iova_next; // Next free IOVA address
  bool hasIommu;

  // All groups bound to this container
  std::list<std::shared_ptr<Group>> groups;

  Logger log;
};

} // namespace vfio
} // namespace kernel
} // namespace villas