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Diffstat (limited to 'dev/kernel/src/BitMapMgr.cc')
| -rw-r--r-- | dev/kernel/src/BitMapMgr.cc | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/dev/kernel/src/BitMapMgr.cc b/dev/kernel/src/BitMapMgr.cc new file mode 100644 index 00000000..18b1a156 --- /dev/null +++ b/dev/kernel/src/BitMapMgr.cc @@ -0,0 +1,195 @@ +/* ------------------------------------------- + + Copyright (C) 2024-2025, Amlal EL Mahrouss, all rights reserved. + +------------------------------------------- */ + +#include <ArchKit/ArchKit.h> + +#ifdef __NE_AMD64__ +#include <HALKit/AMD64/Paging.h> +#elif defined(__NE_ARM64__) +#include <HALKit/ARM64/Paging.h> +#endif + +#include <NewKit/Defines.h> +#include <NewKit/KernelPanic.h> + +#define kBitMapMagic (0x10210U) +#define kBitMapPadSize (mib_cast(16)) + +#define kBitMapMagIdx (0U) +#define kBitMapSizeIdx (1U) +#define kBitMapUsedIdx (2U) + +namespace NeOS +{ + namespace HAL + { + namespace Detail + { + /// \brief Proxy Interface to allocate a bitmap. + class IBitMapProxy final + { + public: + explicit IBitMapProxy() = default; + ~IBitMapProxy() = default; + + NE_COPY_DELETE(IBitMapProxy); + + auto IsBitMap(VoidPtr page_ptr) -> Bool + { + if (!page_ptr) + return No; + + UIntPtr* ptr_bit_set = reinterpret_cast<UIntPtr*>(page_ptr); + + if (!ptr_bit_set[kBitMapMagIdx] || + ptr_bit_set[kBitMapMagIdx] != kBitMapMagic) + return No; + + return Yes; + } + + auto FreeBitMap(VoidPtr page_ptr) -> Bool + { + if (this->IsBitMap(page_ptr) == No) + return No; + + UIntPtr* ptr_bit_set = reinterpret_cast<UIntPtr*>(page_ptr); + + ptr_bit_set[kBitMapMagIdx] = kBitMapMagic; + ptr_bit_set[kBitMapUsedIdx] = No; + + this->GetBitMapStatus(ptr_bit_set); + + return Yes; + } + + UInt32 MakeMMFlags(Bool wr, Bool user) + { + UInt32 flags = kMMFlagsPresent; + + if (wr) + flags |= kMMFlagsWr; + + if (user) + flags |= kMMFlagsUser; + + return flags; + } + + /// @brief Iterate over availables pages for a free one. + /// @return The new address which was found. + auto FindBitMap(VoidPtr base_ptr, SizeT size, Bool wr, Bool user) -> VoidPtr + { + if (!size) + return nullptr; + + VoidPtr base = reinterpret_cast<VoidPtr>(((UIntPtr)base_ptr) + kPageSize); + + static SizeT biggest_block = 0UL; + + while (YES) + { + UIntPtr* ptr_bit_set = reinterpret_cast<UIntPtr*>(base); + + if (ptr_bit_set[kBitMapMagIdx] == kBitMapMagic && + ptr_bit_set[kBitMapSizeIdx] == size) + { + if (ptr_bit_set[kBitMapUsedIdx] == No) + { + ptr_bit_set[kBitMapSizeIdx] = size; + ptr_bit_set[kBitMapUsedIdx] = Yes; + + this->GetBitMapStatus(ptr_bit_set); + + UInt32 flags = this->MakeMMFlags(wr, user); + mm_map_page(ptr_bit_set, ptr_bit_set, flags); + + if (biggest_block < size) + biggest_block = size; + + return (VoidPtr)ptr_bit_set; + } + } + else if (ptr_bit_set[kBitMapMagIdx] != kBitMapMagic) + { + ptr_bit_set[kBitMapMagIdx] = kBitMapMagic; + ptr_bit_set[kBitMapSizeIdx] = size; + ptr_bit_set[kBitMapUsedIdx] = Yes; + + this->GetBitMapStatus(ptr_bit_set); + + UInt32 flags = this->MakeMMFlags(wr, user); + mm_map_page(ptr_bit_set, ptr_bit_set, flags); + + if (biggest_block < size) + biggest_block = size; + + return (VoidPtr)ptr_bit_set; + } + + base = reinterpret_cast<VoidPtr>(reinterpret_cast<UIntPtr>(base) + ((ptr_bit_set[kBitMapMagIdx] != kBitMapMagic) ? (size) : ptr_bit_set[kBitMapSizeIdx])); + } + + return nullptr; + } + + /// @brief Print Bitmap status + auto GetBitMapStatus(UIntPtr* ptr_bit_set) -> Void + { + if (!this->IsBitMap(ptr_bit_set)) + { + kout << "Not a BitMap: " << hex_number((UIntPtr)ptr_bit_set) << kendl; + return; + } + + kout << "Magic Number: " << hex_number(ptr_bit_set[kBitMapMagIdx]) << kendl; + kout << "Is Allocated: " << (ptr_bit_set[kBitMapUsedIdx] ? "Yes" : "No") << kendl; + kout << "Size of BitMap (B): " << number(ptr_bit_set[kBitMapSizeIdx]) << kendl; + kout << "Size of BitMap (KIB): " << number(KIB(ptr_bit_set[kBitMapSizeIdx])) << kendl; + kout << "Size of BitMap (MIB): " << number(MIB(ptr_bit_set[kBitMapSizeIdx])) << kendl; + kout << "Size of BitMap (GIB): " << number(GIB(ptr_bit_set[kBitMapSizeIdx])) << kendl; + kout << "Size of BitMap (TIB): " << number(TIB(ptr_bit_set[kBitMapSizeIdx])) << kendl; + kout << "Address Of BitMap Header: " << hex_number((UIntPtr)ptr_bit_set) << kendl; + } + }; + } // namespace Detail + + auto mm_is_bitmap(VoidPtr ptr) -> Bool + { + Detail::IBitMapProxy bitmp; + return bitmp.IsBitMap(ptr); + } + + /// @brief Allocate a new page to be used by the OS. + /// @param wr read/write bit. + /// @param user user bit. + /// @return a new bitmap allocated pointer. + auto mm_alloc_bitmap(Boolean wr, Boolean user, SizeT size, Bool is_page) -> VoidPtr + { + VoidPtr ptr_new = nullptr; + Detail::IBitMapProxy bitmp; + + ptr_new = bitmp.FindBitMap(kKernelBitMpStart, size, wr, user); + + MUST_PASS(ptr_new); + + return (UIntPtr*)ptr_new; + } + + /// @brief Free Bitmap, and mark it as absent. + /// @param ptr the pointer to free. + auto mm_free_bitmap(VoidPtr ptr) -> Bool + { + if (!ptr) + return No; + + Detail::IBitMapProxy bitmp; + Bool ret = bitmp.FreeBitMap(ptr); + + return ret; + } + } // namespace HAL +} // namespace NeOS |