src/mem/backdoor_manager.hh

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#ifndef __MEM_BACKDOOR_MANAGER_HH__
#define __MEM_BACKDOOR_MANAGER_HH__

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

#include "mem/backdoor.hh"
#include "mem/packet.hh"

namespace gem5
{

/**
 * This class manages the backdoors for RangeAddrMapper. It provides
 * functionalities such as backdoor remapping, resource managing.
 */
class BackdoorManager
{
  public:
    explicit BackdoorManager(const std::vector<AddrRange> &original_ranges,
                             const std::vector<AddrRange> &remapped_ranges);

    MemBackdoorPtr getRevertedBackdoor(MemBackdoorPtr backdoor,
                                       const AddrRange &pkt_range);

  protected:
    /**
     * This function creates a new backdoor, whose address range contains the
     * original request address. The address range is in initiator address
     * view, and shouldn't exceed the original address range.
     */
    MemBackdoorPtr createRevertedBackdoor(MemBackdoorPtr backdoor,
                                          const AddrRange &pkt_range);
    /**
     * This function returns a created backdoor that fulfills the request, or
     * returns nullptr if there's no.
     */
    MemBackdoorPtr findBackdoor(const AddrRange &pkt_range) const;

    const std::vector<AddrRange> &originalRanges;
    const std::vector<AddrRange> &remappedRanges;

    /**
     * In this vector, each entry contains a list of backdoors that in the
     * range in original address view.
     */
    std::vector<std::list<std::unique_ptr<MemBackdoor>>> backdoorLists;
};
}  // namespace gem5

#endif  //__MEM_BACKDOOR_MANAGER_HH__