/*
 * Copyright 2010, Ingo Weinhold, ingo_weinhold@gmx.de.
 * Distributed under the terms of the MIT License.
 */
#ifndef KERNEL_ARCH_X86_PAGING_32_BIT_X86_PAGING_METHOD_32_BIT_H
#define KERNEL_ARCH_X86_PAGING_32_BIT_X86_PAGING_METHOD_32_BIT_H


#include "paging/32bit/paging.h"
#include "paging/X86PagingMethod.h"
#include "paging/X86PagingStructures.h"


class TranslationMapPhysicalPageMapper;
class X86PhysicalPageMapper;


class X86PagingMethod32Bit final : public X86PagingMethod {
public:
                                                                X86PagingMethod32Bit();
        virtual                                         ~X86PagingMethod32Bit();

        virtual status_t                        Init(kernel_args* args,
                                                                        VMPhysicalPageMapper** _physicalPageMapper);
        virtual status_t                        InitPostArea(kernel_args* args);

        virtual status_t                        CreateTranslationMap(bool kernel,
                                                                        VMTranslationMap** _map);

        virtual status_t                        MapEarly(kernel_args* args,
                                                                        addr_t virtualAddress,
                                                                        phys_addr_t physicalAddress,
                                                                        uint8 attributes);

        virtual bool                            IsKernelPageAccessible(addr_t virtualAddress,
                                                                        uint32 protection);

        inline  page_table_entry*       PageHole() const
                                                                        { return fPageHole; }
        inline  page_directory_entry* PageHolePageDir() const
                                                                        { return fPageHolePageDir; }
        inline  uint32                          KernelPhysicalPageDirectory() const
                                                                        { return fKernelPhysicalPageDirectory; }
        inline  page_directory_entry* KernelVirtualPageDirectory() const
                                                                        { return fKernelVirtualPageDirectory; }
        inline  X86PhysicalPageMapper* PhysicalPageMapper() const
                                                                        { return fPhysicalPageMapper; }
        inline  TranslationMapPhysicalPageMapper* KernelPhysicalPageMapper() const
                                                                        { return fKernelPhysicalPageMapper; }

        static  X86PagingMethod32Bit* Method();

        static  void                            PutPageTableInPageDir(
                                                                        page_directory_entry* entry,
                                                                        phys_addr_t pgtablePhysical,
                                                                        uint32 attributes);
        static  void                            PutPageTableEntryInTable(
                                                                        page_table_entry* entry,
                                                                        phys_addr_t physicalAddress,
                                                                        uint32 attributes, uint32 memoryType,
                                                                        bool globalPage);
        static  page_table_entry        SetPageTableEntry(page_table_entry* entry,
                                                                        page_table_entry newEntry);
        static  page_table_entry        SetPageTableEntryFlags(page_table_entry* entry,
                                                                        uint32 flags);
        static  page_table_entry        TestAndSetPageTableEntry(
                                                                        page_table_entry* entry,
                                                                        page_table_entry newEntry,
                                                                        page_table_entry oldEntry);
        static  page_table_entry        ClearPageTableEntry(page_table_entry* entry);
        static  page_table_entry        ClearPageTableEntryFlags(
                                                                        page_table_entry* entry, uint32 flags);

        static  uint32                          MemoryTypeToPageTableEntryFlags(
                                                                        uint32 memoryType);

private:
                        struct PhysicalPageSlotPool;
                        friend struct PhysicalPageSlotPool;

private:
        inline  int32                           _GetInitialPoolCount();

        static  void                            _EarlyPreparePageTables(
                                                                        page_table_entry* pageTables,
                                                                        addr_t address, size_t size);
        static  status_t                        _EarlyQuery(addr_t virtualAddress,
                                                                        phys_addr_t *_physicalAddress);

private:
                        page_table_entry*       fPageHole;
                        page_directory_entry* fPageHolePageDir;
                        uint32                          fKernelPhysicalPageDirectory;
                        page_directory_entry* fKernelVirtualPageDirectory;

                        X86PhysicalPageMapper* fPhysicalPageMapper;
                        TranslationMapPhysicalPageMapper* fKernelPhysicalPageMapper;
};


/*static*/ inline X86PagingMethod32Bit*
X86PagingMethod32Bit::Method()
{
        return static_cast<X86PagingMethod32Bit*>(gX86PagingMethod);
}


/*static*/ inline page_table_entry
X86PagingMethod32Bit::SetPageTableEntry(page_table_entry* entry,
        page_table_entry newEntry)
{
        return atomic_get_and_set((int32*)entry, newEntry);
}


/*static*/ inline page_table_entry
X86PagingMethod32Bit::SetPageTableEntryFlags(page_table_entry* entry,
        uint32 flags)
{
        return atomic_or((int32*)entry, flags);
}


/*static*/ inline page_table_entry
X86PagingMethod32Bit::TestAndSetPageTableEntry(page_table_entry* entry,
        page_table_entry newEntry, page_table_entry oldEntry)
{
        return atomic_test_and_set((int32*)entry, newEntry, oldEntry);
}


/*static*/ inline page_table_entry
X86PagingMethod32Bit::ClearPageTableEntry(page_table_entry* entry)
{
        return SetPageTableEntry(entry, 0);
}


/*static*/ inline page_table_entry
X86PagingMethod32Bit::ClearPageTableEntryFlags(page_table_entry* entry, uint32 flags)
{
        return atomic_and((int32*)entry, ~flags);
}


/*static*/ inline uint32
X86PagingMethod32Bit::MemoryTypeToPageTableEntryFlags(uint32 memoryType)
{
        switch (memoryType) {
                case B_UNCACHED_MEMORY:
                        return X86_PTE_CACHING_DISABLED | X86_PTE_WRITE_THROUGH;

                case B_WRITE_COMBINING_MEMORY:
                        if (x86_use_pat())
                                return X86_PTE_PAT;

                        // X86_PTE_WRITE_THROUGH would be closer, but the combination with
                        // MTRR WC is "implementation defined" for Pentium Pro/II.
                        return 0;

                case B_WRITE_THROUGH_MEMORY:
                        return X86_PTE_WRITE_THROUGH;

                case B_WRITE_PROTECTED_MEMORY:
                case B_WRITE_BACK_MEMORY:
                default:
                        return 0;
        }
}


#endif  // KERNEL_ARCH_X86_PAGING_32_BIT_X86_PAGING_METHOD_32_BIT_H