Rework memory management.

This commit is contained in:
Curle 2020-08-31 21:47:52 +01:00
parent be4ee498c4
commit 6faadded24
Signed by: TheCurle
GPG Key ID: 5942F13718443F79
6 changed files with 1877 additions and 307 deletions

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@ -1,12 +1,18 @@
#include <stddef.h> #include <stddef.h>
#include <stdint.h> #include <stdint.h>
#include <kernel/system/interrupts.h> #include <kernel/system/interrupts.h>
#include <lainlib/lainlib.h>
/************************ /************************
*** Team Kitty, 2020 *** *** Team Kitty, 2020 ***
*** Chroma *** *** Chroma ***
***********************/ ***********************/
/************************************************
* C O N S T A N T S A N D M A C R O S
*************************************************/
#define PAGE_SIZE 4096 #define PAGE_SIZE 4096
#define PAGES_PER_BUCKET 8 #define PAGES_PER_BUCKET 8
@ -16,6 +22,20 @@
#define READ_BIT(i) ((OFFSET_BIT(i) >> (i % PAGES_PER_BUCKET)) & 0x1) #define READ_BIT(i) ((OFFSET_BIT(i) >> (i % PAGES_PER_BUCKET)) & 0x1)
#define GET_BUCKET32(i) (*((uint32_t*) (&Memory[i / 32]))) #define GET_BUCKET32(i) (*((uint32_t*) (&Memory[i / 32])))
#define CAST(a, b) ((a) (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define REINTERPRET_CAST(target, intermediate, value) ((target*)((intermediate*)value))
#define CONCAT(x, y) x ## y
#define CONCAT2(x, y) CONCAT(x, y)
#define ASSERT(exp, error) \
if(!(exp)) SomethingWentWrong(error);
// typedef char CONCAT2(static_assert, __LINE__) [(exp) ? 1 : -1]
#define CLZ(num) (num ? __builtin_clzll(num) : 64)
#define IS_ALIGNED(addr) (((size_t) addr | 0xFFFFFFFFFFFFF000) == 0) #define IS_ALIGNED(addr) (((size_t) addr | 0xFFFFFFFFFFFFF000) == 0)
#define PAGE_ALIGN(addr) ((((size_t) addr) & 0xFFFFFFFFFFFFF000) + 0x1000) #define PAGE_ALIGN(addr) ((((size_t) addr) & 0xFFFFFFFFFFFFF000) + 0x1000)
@ -33,15 +53,175 @@
#define ERR_INST 0x10 #define ERR_INST 0x10
/*
* The way we boot, using BOOTBOOT, and the static hard drive images, means
* we're limited to Protocol 1 - we cannot ask the bootloader to move anything
* around for us.
*
* That means we need to account for these unmovable sections in the paging system.
*
* MMIO_REGION
* Represents the MMIO symbol defined in the linkerscript and chroma.h.
* FB_REGION
* Represents the framebuffer used throughout the kernel.
* This is likely the most important thing to keep where it is. Without this, we
* have no video output.
* KERNEL_REGION
* This is where the kernel itself is loaded into memory. Protocol 1 means
* we're loaded into the -2MB area.
* We *CAN* mvoe the kernel about in memory. It's as simple as memcpying it around
* and calling a void pointer as a function to return to where we were.
* We *CANNOT* move the framebuffer in this manner, as it is set directly by BIOS,
* and the graphics device most likely will not allow this to happen.
* For this reason, the kernel, framebuffer and MMIO will remain where they are.
* Luckily, there are more components of Chroma than the kernel itself. That's what
* the kernel heap and kernel stack areas are for.
*
* USER_REGION
* This is the dedicated space 0...7FFFFFFFFFFF for userspace.
* No kernel objects or data will be put into this space.
* Protocol 1 puts the page tables at 0xA000 by default, so these will have to be moved
* up to kernel space.
*
* KERNEL_STACK_REGION
* KERNEL_STACK_END
* Encapsulate a 1GB large area of memory, to be used by the kernel for thread & interrupt stacks,
* call unwinding and other debug information.
*
* KERNEL_HEAP_REGION
* KERNEL_HEAP_END
* Encapsulate another 1GB large area for kernel objects. ie. resources (images, sounds), libraries,
* data structures, assorted information about the system.. etc.
*
* DIRECT_REGION
* As mentioned above, the lower half is reserved for user space.
* The higher half will be direct-mapped throughout.
* This is the cutoff for the higher half - FFFF800000000000.
*
*/
#define MMIO_REGION 0xFFFFFFFFF8000000ull // Cannot move!
#define FB_REGION 0xFFFFFFFFFC000000ull // Cannot move!
#define FB_PHYSICAL 0x00000000E0000000ull // Physical location of the Framebuffer
#define KERNEL_REGION 0xFFFFFFFFFFE00000ull // -2MiB, from bootloader
#define KERNEL_PHYSICAL 0x0000000000008000ull // Physical location of the kernel
#define KERNEL_PHYSICAL_2 0x000000000011C000ull // For some reason the kernel is split in half
#define USER_REGION 0x00007FFFFFFFFFFFull // Not needed yet, but we're higher half so we might as well be thorough
#define KERNEL_STACK_REGION 0xFFFFE00000000000ull // Kernel Stack Space
#define KERNEL_STACK_END 0xFFFFE00040000000ull // End of Kernel Stack Space
#define KERNEL_HEAP_REGION 0xFFFFE00080000000ull // Kernel Object Space (kmalloc will allocate into this region)
#define KERNEL_HEAP_END 0xFFFFE000C0000000ull // End of Kernel Object Space
#define DIRECT_REGION 0xFFFF800000000000ull
#define LOWER_REGION 0x0000000100000000ull // Lower Memory cutoff - 4GB
#define PAGE_SHIFT 12
/*********************************************
* T Y P E D E F I N I T I O N S
**********************************************/
typedef void* directptr_t;
typedef struct {
ticketlock_t Lock;
directptr_t PML4;
} address_space_t;
typedef enum {
MAP_WRITE = 0x1,
MAP_EXEC = 0x2,
} mapflags_t;
typedef enum {
CACHE_NONE,
CACHE_WRITE_THROUGH,
CACHE_WRITE_BACK,
CACHE_WRITE_COMBINING
} pagecache_t;
typedef struct {
int MaxOrder;
directptr_t Base;
directptr_t* List;
ticketlock_t Lock;
} buddy_t;
/*********************************************
* A b s t r a c t A l l o c a t o r
**********************************************/
const char* IntToAscii(int In);
typedef void* allocator_t;
typedef void* mempool_t;
allocator_t CreateAllocator(void* Memory);
allocator_t CreateAllocatorWithPool(void* Memory, size_t Bytes);
void DestroyAllocator(allocator_t Allocator);
mempool_t GetPoolFromAllocator(allocator_t Allocator);
mempool_t AddPoolToAllocator(allocator_t Allocator, void* Memory, size_t Bytes);
void RemovePoolFromAllocator(allocator_t Allocator, mempool_t pool);
void* AllocatorMalloc (allocator_t Allocator, size_t Bytes);
void* AllocatorMalign (allocator_t Allocator, size_t Alignment, size_t Bytes);
void* AllocatorRealloc(allocator_t Allocator, void* VirtualAddress, size_t NewSize);
void AllocatorFree (allocator_t Allocator, void* VirtualAddress);
size_t AllocatorGetBlockSize(void* VirtualAddress);
size_t AllocatorSize(void);
size_t AllocatorAlignSize(void);
size_t AllocatorMinBlockSize(void);
size_t AllocatorMaxBlockSize(void);
size_t AllocatorPoolOverhead(void);
size_t AllocatorAllocateOverhead(void);
size_t AlignUpwards(size_t Pointer, size_t Alignment);
size_t AlignDownwards(size_t Pointer, size_t Alignment);
void* AlignPointer(const void* Pointer, size_t Alignment);
/************************************************************
* C h r o m a M e m o r y M a n a g e m e n t
*************************************************************/
extern size_t end; extern size_t end;
void ListMemoryMap(); void ListMemoryMap();
void InitMemoryManager(); void InitMemoryManager();
size_t AllocateFrame(); void AddRangeToPhysMem(directptr_t Base, size_t Size);
void FreeFrame(size_t FrameNumber); directptr_t PhysAllocateLowMem(size_t Size);
directptr_t PhysAllocateMem(size_t Size);
directptr_t PhysAllocateZeroMem(size_t Size);
directptr_t PhysAllocateLowZeroMem(size_t Size);
directptr_t PhysAllocatePage();
void PhysRefPage(directptr_t Page);
void PhysFreePage(directptr_t Page);
void FreePhysMem(directptr_t Phys);
size_t SeekFrame(); size_t SeekFrame();
@ -49,4 +229,30 @@ void MemoryTest();
void InitPaging(); void InitPaging();
void PageFaultHandler(INTERRUPT_FRAME frame); void TraversePageTables();
void* memcpy(void* dest, void const* src, size_t len);
/*********************************************
* C h r o m a A l l o c a t o r
**********************************************/
void SetAddressSpace(address_space_t* Space);
//TODO: Copy to/from Userspace
void MapVirtualMemory(address_space_t* Space, void* VirtualAddress, size_t PhysicalAddress, mapflags_t Flags);
void UnmapVirtualMemory(address_space_t* Space, void* VirtualAddress);
void CacheVirtualMemory(address_space_t* Space, void* VirtualAddress, pagecache_t CacheType);
void* AllocateMemory(size_t Bits);
void* ReallocateMemory(void* VirtualAddress, size_t NewSize);
void FreeMemory(void* VirtualAddress);
void* AllocateKernelStack();
void FreeKernelStack(void* StackAddress);
void PageFaultHandler(INTERRUPT_FRAME Frame);

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@ -0,0 +1,798 @@
#include <stddef.h>
#include <stdbool.h>
#include <stdint.h>
#include <kernel/system/memory.h>
#include <kernel/system/io.h>
/************************
*** Team Kitty, 2020 ***
*** Chroma ***
***********************/
/************************************************
* C O N S T A N T S A N D M A C R O S
*************************************************/
#define BLOCK_FREE (1 << 0)
#define BLOCK_PREV_FREE (1 << 1)
#define BLOCK_OVERHEAD (sizeof(size_t))
#define BLOCK_OFFSET (offsetof(block_header_t, Size) + sizeof(size_t))
#define BLOCK_MIN_SIZE (sizeof(block_header_t) - sizeof(block_header_t*))
#define BLOCK_MAX_SIZE (CAST(size_t, 1) << FL_LIMIT)
#define static_assert _Static_assert
extern void SomethingWentWrong(const char* Message);
//#define ASSERT(X) _Static_assert(X)
/************************************************
* S A N I T Y C H E C K S
*************************************************/
//_Static_Assert(sizeof(int) * __CHAR_BIT__ == 32);
//_Static_Assert(sizeof(int) * __CHAR_BIT__ == 32);
//_Static_Assert(sizeof(size_t) * __CHAR_BIT__ >= 32);
//_Static_Assert(sizeof(size_t) * __CHAR_BIT__ <= 64);
//_Static_Assert(sizeof(unsigned int) * __CHAR_BIT__ >= SL_INDEX_COUNT);
//_Static_Assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
/************************************************
* F F S A N D F L S
*************************************************/
#ifdef _cplusplus
#define alloc_decl inline
#else
#define alloc_decl static
#endif
alloc_decl int Alloc_FindFirstOne(unsigned int word) {
return __builtin_ffs(word) - 1;
}
alloc_decl int Alloc_FindLastOne(unsigned int word) {
const int bit = word ? 32 - __builtin_clz(word) : 0;
return bit -1;
}
alloc_decl int Alloc_FindLastOne_64(size_t size) {
int high = (int)(size >> 32);
int bits = 0;
if(high)
bits = 32 + Alloc_FindLastOne(high);
else
bits = Alloc_FindLastOne((int)size & 0xFFFFFFFF);
return bits;
}
#undef alloc_decl
/*********************************************
* T Y P E D E F I N I T I O N S
**********************************************/
enum Alloc_Public {
SL_LIMIT_LN = 5,
};
enum Alloc_Private {
ALIGN_SIZE_LN = 3,
ALIGN_SIZE = (1 << ALIGN_SIZE_LN),
FL_LIMIT = 32,
SL_INDEX_COUNT = (1 << SL_LIMIT_LN),
FL_INDEX_SHIFT = (SL_LIMIT_LN + ALIGN_SIZE_LN),
FL_INDEX_COUNT = (FL_LIMIT - FL_INDEX_SHIFT + 1),
SMALL_BLOCK_SIZE = (1 << FL_INDEX_SHIFT),
};
typedef struct block_header_t {
struct block_header_t* LastBlock;
size_t Size; // Not including this header
struct block_header_t* NextFreeBlock;
struct block_header_t* LastFreeBlock;
} block_header_t ;
typedef struct allocator_control_t {
block_header_t BlockNull;
unsigned int FirstLevel_Bitmap;
unsigned int SecondLevel_Bitmap[FL_INDEX_COUNT];
block_header_t* Blocks[FL_INDEX_COUNT][SL_INDEX_COUNT];
} allocator_control_t;
/**********************************************************************************
* B L O C K _ H E A D E R _ T M E M B E R F U N C T I O N S
************************************************************************************/
static size_t BlockSize(const block_header_t* Block) {
return Block->Size & ~(BLOCK_FREE | BLOCK_PREV_FREE);
}
static void BlockSetSize(block_header_t* Block, size_t Size) {
Block->Size = Size | (Block->Size & (BLOCK_FREE | BLOCK_PREV_FREE));
}
static int BlockIsLast(const block_header_t* Block) {
return BlockSize(Block) == 0;
}
static int BlockIsFree(const block_header_t* Block) {
return CAST(int, Block->Size & BLOCK_FREE);
}
static void BlockSetFree(block_header_t* Block) {
Block->Size |= BLOCK_FREE;
}
static void BlockSetUsed(block_header_t* Block) {
Block->Size &= ~BLOCK_FREE;
}
static int BlockPrevIsFree(const block_header_t* Block) {
return CAST(int, Block->Size & BLOCK_PREV_FREE);
}
static void BlockSetPrevFree(block_header_t* Block) {
Block->Size |= BLOCK_PREV_FREE;
}
static void BlockSetPrevUsed(block_header_t* Block) {
Block->Size &= ~BLOCK_PREV_FREE;
}
static block_header_t* WhichBlock(const void* Address) {
return CAST(block_header_t*, CAST(unsigned char*, Address) - BLOCK_OFFSET);
}
static void* WhereBlock(const block_header_t* Block) {
return CAST(void*, CAST(unsigned char*, Block) + BLOCK_OFFSET);
}
static block_header_t* OffsetToBlock(const void* Address, size_t Size) {
return CAST(block_header_t*, CAST(ptrdiff_t, Address) + Size);
}
static block_header_t* BlockGetPrevious(const block_header_t* Current) {
ASSERT(BlockPrevIsFree(Current), "BlockGetPrevious: Previous block NOT free");
return Current->LastBlock;
}
static block_header_t* BlockGetNext(const block_header_t* Current) {
block_header_t* NextBlock = OffsetToBlock(WhereBlock(Current), BlockSize(Current) - BLOCK_OVERHEAD);
ASSERT(!BlockIsLast(Current), "BlockGetNext: Current block is last!");
return NextBlock;
}
static block_header_t* BlockLinkToNext(block_header_t* Current) {
block_header_t* NextBlock = BlockGetNext(Current);
NextBlock->LastBlock = Current;
return NextBlock;
}
static void BlockMarkFree(block_header_t* Current) {
block_header_t* NextBlock = BlockLinkToNext(Current);
BlockSetPrevFree(NextBlock);
BlockSetFree(Current);
}
static void BlockMarkUsed(block_header_t* Current) {
block_header_t* NextBlock = BlockGetNext(Current);
BlockSetPrevUsed(NextBlock);
BlockSetUsed(Current);
}
/***********************************************************************************
* P O I N T E R A L I G N M E N T F U N C T I O N S
************************************************************************************/
size_t AlignUpwards(size_t Pointer, size_t Alignment) {
//ASSERT(((Alignment & (Alignment - 1)) == 0));
return (Pointer + (Alignment - 1)) & ~(Alignment - 1);
}
size_t AlignDownwards(size_t Pointer, size_t Alignment) {
//ASSERT((Alignment & (Alignment - 1) == 0));
return (Pointer - (Pointer & (Alignment - 1)));
}
void* AlignPointer(const void* Pointer, size_t Alignment) {
const ptrdiff_t AlignedPointer =
((
CAST(ptrdiff_t, Pointer)
+ (Alignment - 1))
& ~(Alignment - 1)
);
ASSERT(((Alignment & (Alignment - 1)) == 0), "AlignPointer: Requested alignment not aligned!");
return CAST(void*, AlignedPointer);
}
/***********************************************************************************
* M E M O R Y B L O C K M A N A G E M E N T
************************************************************************************/
static size_t AlignRequestSize(size_t Size, size_t Alignment) {
size_t Adjustment = 0;
if(Size) {
const size_t Aligned = AlignUpwards(Size, Alignment);
if(Aligned < BLOCK_MAX_SIZE)
Adjustment = MAX(Aligned, BLOCK_MIN_SIZE);
}
return Adjustment;
}
static void InsertMapping(size_t Size, int* FirstLevelIndex, int* SecondLevelIndex) {
int FirstLevel, SecondLevel;
if(Size < SMALL_BLOCK_SIZE) {
FirstLevel = 0;
SecondLevel = CAST(int, Size) / (SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
} else {
FirstLevel = Alloc_FindLastOne_64(Size);
SecondLevel = CAST(int, Size >> (FirstLevel - SL_LIMIT_LN)) ^ (1 << SL_LIMIT_LN);
FirstLevel -= (FL_INDEX_SHIFT - 1);
}
*FirstLevelIndex = FirstLevel;
*SecondLevelIndex = SecondLevel;
}
static void RoundUpBlockSize(size_t Size, int* FirstLevelIndex, int* SecondLevelIndex) {
if(Size >= SMALL_BLOCK_SIZE) {
const size_t Rounded = (1 << (Alloc_FindLastOne_64(Size) - SL_LIMIT_LN)) - 1;
Size += Rounded;
}
InsertMapping(Size, FirstLevelIndex, SecondLevelIndex);
}
static block_header_t* FindSuitableBlock(allocator_control_t* Controller, int* FirstLevelIndex, int* SecondLevelIndex) {
int FirstLevel = *FirstLevelIndex;
int SecondLevel = *SecondLevelIndex;
unsigned int SLMap = Controller->SecondLevel_Bitmap[FirstLevel] & (~0U << SecondLevel);
if(!SLMap) {
const unsigned int FLMap = Controller->FirstLevel_Bitmap & (~0U << (FirstLevel + 1));
if(!FLMap)
return 0;
FirstLevel = Alloc_FindFirstOne(FLMap);
*FirstLevelIndex = FirstLevel;
SLMap = Controller->SecondLevel_Bitmap[FirstLevel];
}
ASSERT(SLMap, "FindSuitableBlock: Second level bitmap not present!");
SecondLevel = Alloc_FindFirstOne(SLMap);
*SecondLevelIndex = SecondLevel;
return Controller->Blocks[FirstLevel][SecondLevel];
}
static void RemoveFreeBlock(allocator_control_t* Controller, block_header_t* Block, int FirstLevel, int SecondLevel) {
block_header_t* PreviousBlock = Block->LastFreeBlock;
block_header_t* NextBlock = Block->NextFreeBlock;
ASSERT(PreviousBlock, "RemoveFreeBlock: PreviousBlock is null!");
ASSERT(NextBlock, "RemoveFreeBlock: NextBlock is null!");
NextBlock->LastFreeBlock = PreviousBlock;
PreviousBlock->NextFreeBlock = NextBlock;
if(Controller->Blocks[FirstLevel][SecondLevel] == Block) {
Controller->Blocks[FirstLevel][SecondLevel] = NextBlock;
if(NextBlock == &Controller->BlockNull) {
Controller->SecondLevel_Bitmap[FirstLevel] &= ~(1U << SecondLevel);
if(!Controller->SecondLevel_Bitmap[FirstLevel]) {
Controller->FirstLevel_Bitmap &= ~(1U << FirstLevel);
}
}
}
}
static void InsertFreeBlock(allocator_control_t* Controller, block_header_t* NewBlock, int FirstLevel, int SecondLevel) {
block_header_t* Current = Controller->Blocks[FirstLevel][SecondLevel];
ASSERT(Current, "InsertFreeBlock: Current Block is null!");
if(!Current) {
SerialPrintf("Extra info: \r\n\tFirst Level: %x Second Level: %x\r\nFirst Level bitmap: %x, Second Level bitmap: %x\r\n\tBlocks %x, BlocksAddress: %x", FirstLevel, SecondLevel, Controller->FirstLevel_Bitmap, Controller->SecondLevel_Bitmap, Controller->Blocks, Controller->Blocks[FirstLevel][SecondLevel]);
for(;;){}
}
ASSERT(NewBlock, "InsertFreeBlock: New Block is null!");
NewBlock->NextFreeBlock = Current;
NewBlock->LastFreeBlock = &Controller->BlockNull;
Current->LastFreeBlock = NewBlock;
ASSERT(WhereBlock(NewBlock) == AlignPointer(WhereBlock(NewBlock), ALIGN_SIZE), "InsertFreeBlock: Current block is not memory aligned!");
Controller->Blocks[FirstLevel][SecondLevel] = NewBlock;
Controller->FirstLevel_Bitmap |= (1U << FirstLevel);
Controller->SecondLevel_Bitmap[FirstLevel] |= (1U << SecondLevel);
}
static void RemoveBlock(allocator_control_t* Controller, block_header_t* Block) {
int FirstLevel, SecondLevel;
InsertMapping(BlockSize(Block), &FirstLevel, &SecondLevel);
RemoveFreeBlock(Controller, Block, FirstLevel, SecondLevel);
}
static void InsertBlock(allocator_control_t* Controller, block_header_t* Block) {
int FirstLevel, SecondLevel;
InsertMapping(BlockSize(Block), &FirstLevel, &SecondLevel);
InsertFreeBlock(Controller, Block, FirstLevel, SecondLevel);
}
static int CanBlockSplit(block_header_t* Block, size_t NewSize) {
return BlockSize(Block) >= sizeof(block_header_t) + NewSize;
}
static block_header_t* SplitBlock(block_header_t* Block, size_t NewSize) {
block_header_t* Overlap = OffsetToBlock(WhereBlock(Block), NewSize - BLOCK_OVERHEAD);
const size_t RemainingSize = BlockSize(Block) - (NewSize + BLOCK_OVERHEAD);
ASSERT(WhereBlock(Overlap) == AlignPointer(WhereBlock(Overlap), ALIGN_SIZE), "SplitBlock: Requested size results in intermediary block which is not aligned!");
ASSERT(BlockSize(Block) == RemainingSize + NewSize + BLOCK_OVERHEAD, "SplitBlock: Maths error!");
BlockSetSize(Overlap, RemainingSize);
ASSERT(BlockSize(Overlap) >= BLOCK_MIN_SIZE, "SplitBlock: Requested size results in new block that is too small!");
BlockSetSize(Block, NewSize);
BlockMarkFree(Overlap);
return Overlap;
}
static block_header_t* MergeBlockDown(block_header_t* Previous, block_header_t* Block) {
ASSERT(!BlockIsLast(Previous), "MergeBlockDown: Previous block is the last block! (Current block is first block?)");
Previous->Size += BlockSize(Block) + BLOCK_OVERHEAD;
BlockLinkToNext(Previous);
return Previous;
}
static block_header_t* MergeEmptyBlockDown(allocator_control_t* Controller, block_header_t* Block) {
if(BlockPrevIsFree(Block)) {
block_header_t* Previous = BlockGetPrevious(Block);
ASSERT(Previous, "MergeEmptyBlockDown: Previous block is null!");
ASSERT(BlockIsFree(Previous), "MergeEmptyBlockDown: Previous block is free!");
RemoveBlock(Controller, Previous);
Block = MergeBlockDown(Previous, Block);
}
return Block;
}
static block_header_t* MergeNextBlockDown(allocator_control_t* Controller, block_header_t* Block) {
block_header_t* NextBlock = BlockGetNext(Block);
ASSERT(NextBlock, "MergeNextBlockDown: Next Block is null!");
if(BlockIsFree(NextBlock)) {
ASSERT(!BlockIsLast(Block), "MergeNextBlockDown: Current block is the last block!");
RemoveBlock(Controller, NextBlock);
Block = MergeBlockDown(Block, NextBlock);
}
return Block;
}
static void TrimBlockFree(allocator_control_t* Controller, block_header_t* Block, size_t Size) {
ASSERT(BlockIsFree(Block), "TrimBlockFree: Current block is wholly free!");
if(CanBlockSplit(Block, Size)) {
block_header_t* RemainingBlock = SplitBlock(Block, Size);
BlockLinkToNext(Block);
BlockSetPrevFree(RemainingBlock);
InsertBlock(Controller, RemainingBlock);
}
}
static void TrimBlockUsed(allocator_control_t* Controller, block_header_t* Block, size_t Size) {
ASSERT(!BlockIsFree(Block), "TrimBlockUsed: The current block is wholly used!");
if(CanBlockSplit(Block, Size)) {
block_header_t* RemainingBlock = SplitBlock(Block, Size);
BlockSetPrevUsed(RemainingBlock);
RemainingBlock = MergeNextBlockDown(Controller, RemainingBlock);
InsertBlock(Controller, RemainingBlock);
}
}
static block_header_t* TrimBlockLeadingFree(allocator_control_t* Controller, block_header_t* Block, size_t Size) {
block_header_t* RemainingBlock = Block;
if(CanBlockSplit(Block, Size)) {
RemainingBlock = SplitBlock(Block, Size - BLOCK_OVERHEAD);
BlockSetPrevFree(RemainingBlock);
BlockLinkToNext(Block);
InsertBlock(Controller, Block);
}
return RemainingBlock;
}
static block_header_t* LocateFreeBlock(allocator_control_t* Controller, size_t Size) {
int FirstLevel = 0, SecondLevel = 0;
block_header_t* Block = 0;
if(Size) {
RoundUpBlockSize(Size, &FirstLevel, &SecondLevel);
if(FirstLevel < FL_INDEX_COUNT) {
Block = FindSuitableBlock(Controller, &FirstLevel, &SecondLevel);
}
}
if(Block) {
ASSERT(BlockSize(Block) >= Size, "LocateFreeBlock: Found a block that is too small!");
RemoveFreeBlock(Controller, Block, FirstLevel, SecondLevel);
}
return Block;
}
static void* PrepareUsedBlock(allocator_control_t* Controller, block_header_t* Block, size_t Size) {
void* Pointer = 0;
if(Block){
ASSERT(Size, "PrepareUsedBlock: Size is 0!");
TrimBlockFree(Controller, Block, Size);
BlockMarkUsed(Block);
Pointer = WhereBlock(Block);
}
return Pointer;
}
/***********************************************************************************
* C O N T R O L L E R M A N A G E M E N T
************************************************************************************/
static void ConstructController(allocator_control_t* Controller) {
int i, j;
Controller->BlockNull.NextFreeBlock = &Controller->BlockNull;
Controller->BlockNull.LastFreeBlock = &Controller->BlockNull;
Controller->FirstLevel_Bitmap = 0;
for ( i = 0; i < FL_INDEX_COUNT; i++) {
Controller->SecondLevel_Bitmap[i] = 0;
for (j = 0; j < SL_INDEX_COUNT; j++) {
Controller->Blocks[i][j] = &Controller->BlockNull;
}
}
}
/***********************************************************************************
* H E A D E R ( A P I ) F U N C T I O N S
************************************************************************************/
size_t AllocatorGetBlockSize(void* Memory) {
size_t Size = 0;
if(Memory) {
const block_header_t* Block = WhichBlock(Memory);
Size = BlockSize(Block);
}
return Size;
}
size_t AllocatorSize(void) {
return sizeof(allocator_control_t);
}
size_t AllocatorAlignSize(void) {
return ALIGN_SIZE;
}
size_t AllocatorMinBlockSize(void) {
return BLOCK_MIN_SIZE;
}
size_t AllocatorMaxBlockSize(void) {
return BLOCK_MAX_SIZE;
}
size_t AllocatorPoolOverhead(void) {
return 2* BLOCK_OVERHEAD; // Free block + Sentinel block
}
size_t AllocatorAllocateOverhead(void) {
return BLOCK_OVERHEAD;
}
mempool_t AddPoolToAllocator(allocator_t Allocator, void* Address, size_t Size) {
block_header_t* Block;
block_header_t* NextBlock;
const size_t PoolOverhead = AllocatorPoolOverhead();
const size_t PoolBytes = AlignDownwards(Size - PoolOverhead, ALIGN_SIZE);
if(((ptrdiff_t) Address % ALIGN_SIZE) != 0) {
SerialPrintf("Memory manager error at [%s:%x]: Memory not properly aligned.\r\n", __FILE__, __LINE__);
return 0;
}
if( PoolBytes < BLOCK_MIN_SIZE || PoolBytes > BLOCK_MAX_SIZE) {
SerialPrintf("Memory manager error at [%s:%x]: Memory Size out of bounds: 0x%x-0x%x: 0x%x.\r\n", __FILE__, __LINE__, (unsigned int)(PoolOverhead + BLOCK_MIN_SIZE), (unsigned int)(PoolOverhead + BLOCK_MAX_SIZE) / 256, PoolBytes);
return 0;
}
Block = OffsetToBlock(Address, -(ptrdiff_t)BLOCK_OVERHEAD);
BlockSetSize(Block, PoolBytes);
BlockSetFree(Block);
BlockSetPrevUsed(Block);
InsertBlock(CAST(allocator_control_t*, Allocator), Block);
NextBlock = BlockLinkToNext(Block);
BlockSetSize(NextBlock, 0);
BlockSetUsed(NextBlock);
BlockSetPrevFree(NextBlock);
return Address;
}
void RemovePoolFromAllocator(allocator_t Allocator, mempool_t Pool){
allocator_control_t* Controller = CAST(allocator_control_t*, Allocator);
block_header_t* Block = OffsetToBlock(Pool, -(int)BLOCK_OVERHEAD);
int FirstLevel = 0, SecondLevel = 0;
ASSERT(BlockIsFree(Block), "RemovePoolFromAllocator: Current block is free!");
ASSERT(!BlockIsFree(BlockGetNext(Block)), "RemovePoolFromAllocator: Next Block is not free!");
ASSERT(BlockSize(BlockGetNext(Block)) == 0, "RemovePoolFromAllocator: Next block is size 0!");
RoundUpBlockSize(BlockSize(Block), &FirstLevel, &SecondLevel);
RemoveFreeBlock(Controller, Block, FirstLevel, SecondLevel);
}
int TestBuiltins() {
/* Verify ffs/fls work properly. */
int TestsFailed = 0;
TestsFailed += (Alloc_FindFirstOne(0) == -1) ? 0 : 0x1;
TestsFailed += (Alloc_FindLastOne(0) == -1) ? 0 : 0x2;
TestsFailed += (Alloc_FindFirstOne(1) == 0) ? 0 : 0x4;
TestsFailed += (Alloc_FindLastOne(1) == 0) ? 0 : 0x8;
TestsFailed += (Alloc_FindFirstOne(0x80000000) == 31) ? 0 : 0x10;
TestsFailed += (Alloc_FindFirstOne(0x80008000) == 15) ? 0 : 0x20;
TestsFailed += (Alloc_FindLastOne(0x80000008) == 31) ? 0 : 0x40;
TestsFailed += (Alloc_FindLastOne(0x7FFFFFFF) == 30) ? 0 : 0x80;
TestsFailed += (Alloc_FindLastOne_64(0x80000000) == 31) ? 0 : 0x100;
TestsFailed += (Alloc_FindLastOne_64(0x100000000) == 32) ? 0 : 0x200;
TestsFailed += (Alloc_FindLastOne_64(0xffffffffffffffff) == 63) ? 0 : 0x400;
if (TestsFailed) {
SerialPrintf("TestBuiltins: %x ffs/fls tests failed.\n", TestsFailed);
}
return TestsFailed;
}
allocator_t CreateAllocator(void* Memory) {
if(TestBuiltins())
return 0;
if (((ptrdiff_t) Memory % ALIGN_SIZE) != 0) {
SerialPrintf("Memory manager error at [%s:%x]: Memory not properly aligned.\r\n", __FILE__, __LINE__);
return 0;
}
ConstructController(CAST(allocator_control_t*, Memory));
return CAST(allocator_t, Memory);
}
allocator_t CreateAllocatorWithPool(void* Memory, size_t Bytes) {
allocator_t Allocator = CreateAllocator(Memory);
AddPoolToAllocator(Allocator, (char*)Memory + AllocatorSize(), Bytes - AllocatorSize());
return Allocator;
}
void DestroyAllocator(allocator_t Allocator) {
(void) Allocator;
}
mempool_t GetPoolFromAllocator(allocator_t Allocator) {
return CAST(mempool_t, (char*)Allocator + AllocatorSize());
}
/***********************************************************************************
* S T D L I B A L L O C A T E F U N C T I O N S
************************************************************************************/
void* AllocatorMalloc(allocator_t Allocator, size_t Size) {
allocator_control_t* Controller = CAST(allocator_control_t*, Allocator);
const size_t Adjustment = AlignRequestSize(Size, ALIGN_SIZE);
block_header_t* Block = LocateFreeBlock(Controller, Adjustment);
return PrepareUsedBlock(Controller, Block, Adjustment);
}
void* AllocatorMalign(allocator_t Allocator, size_t Alignment, size_t Size) {
allocator_control_t* Controller = CAST(allocator_control_t*, Allocator);
const size_t Adjustment = AlignRequestSize(Size, ALIGN_SIZE);
const size_t MinimumGap = sizeof(block_header_t);
const size_t SizeWithGap = AlignRequestSize(Adjustment + Alignment + MinimumGap, Alignment);
const size_t AlignedSize = (Adjustment && Alignment > ALIGN_SIZE) ? SizeWithGap : Adjustment;
block_header_t* Block = LocateFreeBlock(Controller, AlignedSize);
ASSERT(sizeof(block_header_t) == BLOCK_MIN_SIZE + BLOCK_OVERHEAD, "AllocatorMalign: Maths error!");
if(Block) {
void* Address = WhereBlock(Block);
void* AlignedAddress = AlignPointer(Address, Alignment);
size_t Gap = CAST(size_t, CAST(ptrdiff_t, AlignedAddress) - CAST(ptrdiff_t, Address));
if(Gap) {
if(Gap << MinimumGap) {
const size_t GapRemaining = MinimumGap - Gap;
const size_t Offset = MAX(GapRemaining, Alignment);
const void* NextAlignedAddress = CAST(void*, CAST(ptrdiff_t, AlignedAddress) + Offset);
AlignedAddress = AlignPointer(NextAlignedAddress, Alignment);
Gap = CAST(size_t, CAST(ptrdiff_t, AlignedAddress) - CAST(ptrdiff_t, Address));
}
ASSERT(Gap >= MinimumGap, "AllocatorMalign: Maths error 2!");
Block = TrimBlockLeadingFree(Controller, Block, Gap);
}
}
return PrepareUsedBlock(Controller, Block, Adjustment);
}
void AllocatorFree(allocator_t Allocator, void* Address) {
if(Address) {
allocator_control_t* Controller = CAST(allocator_control_t*, Allocator);
block_header_t* Block = WhichBlock(Address);
ASSERT(!BlockIsFree(Block), "AllocatorFree: Attempting to free a freed block!");
BlockMarkFree(Block);
Block = MergeEmptyBlockDown(Controller, Block);
Block = MergeNextBlockDown(Controller, Block);
InsertBlock(Controller, Block);
}
}
/*
* Realloc should, with:
* * A valid size with an invalid pointer:
* - Allocate space
* * An invalid size with a valid pointer:
* - Free Space
* * An invalid request:
* - Do nothing
* * A valid extension request:
* - Leave the new area as it is
* // TODO: memset this area to 0.
*/
void* AllocatorRealloc(allocator_t Allocator, void* Address, size_t NewSize) {
allocator_control_t* Controller = CAST(allocator_control_t*, Allocator);
void* Pointer = 0;
// Valid address, invalid size; free
if(Address && NewSize == 0)
AllocatorFree(Allocator, Address);
else if (!Address) // Invalid address; alloc
AllocatorMalloc(Allocator, NewSize);
else {
block_header_t* Block = WhichBlock(Address);
block_header_t* NextBlock = BlockGetNext(Block);
const size_t CurrentSize = BlockSize(Block);
const size_t CombinedSize = CurrentSize + BlockSize(NextBlock) + BLOCK_OVERHEAD;
const size_t AdjustedSize = AlignRequestSize(NewSize, ALIGN_SIZE);
ASSERT(!BlockIsFree(Block), "AllocatorRealloc: Requested block is not free!");
if(AdjustedSize > CurrentSize && (!BlockIsFree(NextBlock) || AdjustedSize > CombinedSize)) {
// We're going to need more room
Pointer = AllocatorMalloc(Allocator, NewSize);
if(Pointer) {
const size_t MinimumSize = MIN(CurrentSize, NewSize);
memcpy(Pointer, Address, MinimumSize);
AllocatorFree(Allocator, Address);
}
} else {
if( AdjustedSize > CurrentSize) {
MergeNextBlockDown(Controller, Block);
BlockMarkUsed(Block);
}
TrimBlockUsed(Controller, Block, AdjustedSize);
Pointer = Address;
}
}
return Pointer;
}

View File

@ -0,0 +1,310 @@
void InitPagingT() {
size_t* PML4 = (size_t*) 0xFFA000; // Layer 4
size_t* PDPE_RAM = (size_t*) 0xFFE000; // Layer 3, contains map for the first 4GB of RAM
size_t* PDE_RAM = (size_t*) 0xFFF000;
size_t* PDPE_KERNEL = (size_t*) 0xFFB000; // Layer 3, contains map for the Kernel and everything it needs to run.
size_t* PDE_KERNEL_FB = (size_t*) 0xFFC000; // Layer 2, contains map for the linear framebuffer.
size_t* PT_KERNEL = (size_t*) 0xFFD000; // Layer 1, the page table for the kernel itself.
size_t fb_ptr = (size_t) &fb;
SET_ADDRESS(PML4, PDPE_RAM); // 3rd Layer entry for RAM
SET_ADDRESS(PML4 + LAST_ENTRY, PDPE_KERNEL); // 3rd Layer entry for Kernel
SET_ADDRESS(PDPE_KERNEL + LAST_ENTRY, PDE_KERNEL_FB); // 2nd Layer entry for the framebuffer
// Set the 480th entry (PDE_KERNEL_FB + (480 * 8))
// To the framebuffer + flags
SET_ADDRESS(PDE_KERNEL_FB + 3840, USERWRITEABLE_FLAGS(fb_ptr));
// In 4 byte increments, we're gonna map 3840 (the framebuffer)
// Up to (4096 - 8) in the PDE_KERNEL_FB with 2MB paging.
size_t MappingIterations = 1;
for(size_t i = 3844; i < 4088; i += 4) {
SET_ADDRESS(PDE_KERNEL_FB + i, USERWRITEABLE_FLAGS(fb_ptr) + (MappingIterations * (2 * MiB)));
MappingIterations++;
}
// Now we map the last entry of PDE_KERNEL_FB to our Page Table
SET_ADDRESS(PDE_KERNEL_FB + LAST_ENTRY, PT_KERNEL);
// Mapping the kernel into the page tables....
SET_ADDRESS(PT_KERNEL, 0xFF8001); // bootldr, bootinfo
SET_ADDRESS(PT_KERNEL + 8, 0xFF9001); // environment
// Map the kernel itself
SET_ADDRESS(PT_KERNEL + 16, KernelAddr + 1);
// Iterate through the pages, identity mapping each one
MappingIterations = 1;
size_t MappingOffset = 0x14;
for(size_t i = 0; i < ((KernelEnd - KernelAddr) >> 12); i++) {
// Page Table + (0x10 increasing by 0x04 each time) = x * 4KiB
SET_ADDRESS(PT_KERNEL + MappingOffset, (MappingIterations * (4 * KiB)));
MappingOffset += 4;
MappingIterations++;
}
// Now we need to map the core stacks. Top-down, from 0xDFF8
// There's always at least one core, so we do that one fixed.
// TODO: Account for 0-core CPUs
SET_ADDRESS(PT_KERNEL + LAST_ENTRY, 0xF14003);
MappingIterations = 1;
// For every core:
for(size_t i = 0; i < (bootldr.numcores + 3U) >> 2; i++) {
// PT_KERNEL[512 - (iterations + 1)] = 0x14003 + (iterations * page-width)
SET_ADDRESS(PT_KERNEL + LAST_ENTRY - (MappingIterations * 8), 0xF14003 + (4096 * MappingIterations));
MappingIterations++;
}
SET_ADDRESS(PDPE_RAM, PDE_RAM + PAGE_PRESENT + PAGE_RW);
SET_ADDRESS(PDPE_RAM + 8, 0xF10000 + PAGE_PRESENT + PAGE_RW);
SET_ADDRESS(PDPE_RAM + 16, 0xF11000 + PAGE_PRESENT + PAGE_RW);
SET_ADDRESS(PDPE_RAM + 24, 0xF12000 + PAGE_PRESENT + PAGE_RW);
// Identity map 4GB of ram
// Each page table can only hold 512 entries, but we
// just set up 4 of them - overflowing PDE_RAM (0xF000)
// will take us into 0x10000, into 0x11000, into 0x120000.
for(size_t i = 0; i < 512 * 4/*GB*/; i++) {
// add PDE_RAM, 4
// mov eax, 0x83
// add eax, 2*1024*1024
SET_ADDRESS(PDE_RAM + (i * 4), USERWRITEABLE_FLAGS(i * (2 * MiB)));
}
// Map first 2MB of memory
SET_ADDRESS(PDE_RAM, 0xF13000 + PAGE_PRESENT + PAGE_RW);
for(size_t i = 0; i < 512; i++) {
SET_ADDRESS(0xF13000 + i * 4, i * (4 * KiB) + PAGE_PRESENT + PAGE_RW);
}
// 0xA000 should now contain our memory map.
}
void TraversePageTables() {
}
void InitPagingOldImpl() {
// Disable paging so that we can work with the pagetable
//size_t registerTemp = ReadControlRegister(0);
//UNSET_PGBIT(registerTemp);
//WriteControlRegister(0, registerTemp);
// Clear space for our pagetable
size_t PagetableDest = 0x1000;
memset((char*)PagetableDest, 0, 4096);
// Start setting pagetable indexes
*((size_t*)PagetableDest) = 0x2003; // PDP at 0x2000, present & r/w
*((size_t*)PagetableDest + 0x1000) = 0x3003; // PDT at 0x3000, present & r/w
*((size_t*)PagetableDest + 0x2000) = 0x4003; // PT at 0x4000, present & r/w
size_t value = 0x3;
size_t offset = 8;
for(size_t i = 0; i < 512; i++) { // 512 iterations (entries into the page table)
*((size_t*) PagetableDest + offset) = value; // We're setting 512 bytes with x003
// (identity mapping the first 4 megabytes of memory)
// (mapping the page table to itself)
value += 4096; // Point to start of next page
offset += 8; // + 8 bytes (next entry in list)
}
// Enable PAE paging
size_t reg = ReadControlRegister(4);
SET_PAEBIT(reg);
WriteControlRegister(4, reg);
WriteControlRegister(3, PagetableDest);
}
/* size_t registerTemp = ReadControlRegister(4);
if(registerTemp & (1 << 7)) {
TOGGLE_PGEBIT(registerTemp);
WriteControlRegister(4, registerTemp);
}
if(registerTemp & (1 << 7))
WriteControlRegister(4, registerTemp ^ (1 << 7));
size_t CPUIDReturn;
asm volatile("cpuid" : "=d" (CPUIDReturn) : "a" (0x80000001) : "%rbx", "%rcx");
if(CPUIDReturn & (1 << 26)) {
SerialPrintf("System supports 1GB pages.\r\n");
if(registerTemp & (1 << 12)) {
SerialPrintf("PML5 paging available - using that instead.\r\n");
if(MemorySize > (1ULL << 57))
SerialPrintf("System has over 128Petabytes of RAM. Please consider upgrading the OS on your supercomputer.\r\n");
size_t MaxPML5 = 1;
size_t MaxPML4 = 1;
size_t MaxPDP = 512;
size_t LastPML4Entry = 512;
size_t LastPDPEntry = 512;
size_t MemorySearchDepth = MemorySize;
while(MemorySearchDepth > (256ULL << 30)) {
MaxPML5++;
MemorySearchDepth -= (256ULL << 30);
}
if(MaxPML5 > 512)
MaxPML5 = 512;
if(MemorySearchDepth) {
LastPDPEntry = ( (MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30;
if(MaxPML5 > 512)
MaxPML5 = 512;
}
size_t PML4Size = PAGETABLE_SIZE * MaxPML5;
size_t PDPSize = PML4Size * MaxPML4;
size_t PML4Base = AllocatePagetable(PML4Size + PDPSize);
size_t PDPBase = PML4Base + PML4Size;
for(size_t PML5Entry = 0; PML5Entry < MaxPML5; PML5Entry++) {
Pagetable[PML5Entry] = PML4Base + (PML5Entry << 12);
if(PML5Entry == (MaxPML5 - 1))
MaxPML4 = LastPML4Entry;
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) {
((size_t*) Pagetable[PML5Entry])[PML4Entry] = PDPBase + (((PML5Entry << 9) + PML5Entry) << 12);
if( (PML5Entry == (MaxPML5 - 1)) && (PML4Entry == (MaxPML4 -1)) )
MaxPDP = LastPDPEntry;
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) {
((size_t* ) ((size_t* ) Pagetable[PML5Entry])[PML4Entry])[PDPEntry] = ( ((PML5Entry << 18) + (PML4Entry << 9) + PDPEntry) << 30) | (0x83);
}
((size_t* ) Pagetable[PML5Entry])[PML4Entry] |= 0x3;
}
Pagetable[PML5Entry] |= 0x3;
}
} else {
SerialPrintf("PML4 available - using that instead.\r\n");
size_t MemorySearchDepth = MemorySize;
if(MemorySearchDepth > (1ULL << 48))
SerialPrintf("RAM limited to 256TB.\r\n");
size_t MaxPML4 = 1;
size_t MaxPDP = 512;
size_t LastPDPEntry = 512;
while(MemorySearchDepth > (512ULL << 30)) {
MaxPML4++;
MemorySearchDepth -= (512ULL << 30);
}
if(MaxPML4 > 512)
MaxPML4 = 512;
if(MemorySearchDepth) {
LastPDPEntry = ( (MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30;
if(LastPDPEntry > 512)
LastPDPEntry = 512;
}
size_t PDPSize = PAGETABLE_SIZE * MaxPML4;
size_t PDPBase = AllocatePagetable(PDPSize);
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) {
Pagetable[PML4Entry] = PDPBase + (PML4Entry << 12);
if(PML4Entry == (MaxPML4 - 1)) {
MaxPDP = LastPDPEntry;
}
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) {
((size_t* ) Pagetable[PML4Entry])[PDPEntry] = (((PML4Entry << 9) + PDPEntry) << 30) | 0x83;
}
Pagetable[PML4Entry] |= 0x3;
}
}
} else {
SerialPrintf("System does not support 1GB pages - using 2MiB paging instead.\r\n");
size_t MemorySearchDepth = MemorySize;
if(MemorySearchDepth > (1ULL << 48)) {
SerialPrintf("Usable RAM is limited to 256TB, and the page table alone will use 1GB of space in memory.\r\n");
}
size_t MaxPML4 = 1, MaxPDP = 512, MaxPD = 512, LastPDPEntry = 1;
while(MemorySearchDepth > (512ULL << 30)) {
MaxPML4++;
MemorySearchDepth -= (512ULL << 30);
}
if(MaxPML4 > 512)
MaxPML4 = 512;
if(MemorySearchDepth) {
LastPDPEntry = ((MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30;
if(LastPDPEntry > 512)
LastPDPEntry = 512;
}
size_t PDPSize = PAGETABLE_SIZE * MaxPML4;
size_t PDSize = PDPSize * MaxPDP;
size_t PDPBase = AllocatePagetable(PDPSize + PDSize);
size_t PDBase = PDPBase + PDSize;
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) {
Pagetable[PML4Entry] = PDBase + (PML4Entry << 12);
if(PML4Entry == (MaxPML4 - 1)) {
MaxPDP = LastPDPEntry;
}
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) {
( (size_t* ) Pagetable[PML4Entry])[PDPEntry] = PDBase + (((PML4Entry << 9) + PDPEntry) << 12);
for(size_t PDEntry = 0; PDEntry < MaxPD; PDEntry++) {
( (size_t* ) ((size_t*) Pagetable[PML4Entry])[PDPEntry])[PDEntry] = (( (PML4Entry << 18) + (PDPEntry << 9) + PDPEntry) << 21) | 0x83;
}
( (size_t* ) Pagetable[PML4Entry])[PDPEntry] |= 0x3;
}
Pagetable[PML4Entry] |= 0x3;
}
}
WriteControlRegister(3, Pagetable);
registerTemp = ReadControlRegister(4);
if(!(registerTemp & (1 << 7))) {
TOGGLE_PGEBIT(registerTemp);
WriteControlRegister(4, registerTemp);
}*/

View File

@ -0,0 +1,53 @@
size_t AllocateFrame() {
size_t FreePage = SeekFrame();
SET_BIT(FreePage);
return FreePage;
}
void FreeFrame(size_t Frame) {
UNSET_BIT(Frame);
}
size_t SeekFrame() {
for(size_t i = 0; i < MemoryPages; i++) {
if(!READ_BIT(i))
return i;
}
SerialPrintf("Memory manager: Critical!\r\n");
return (size_t) -1;
}
void MemoryTest() {
SerialPrintf("Initializing basic memory test..\r\n");
bool Passed = true;
size_t FirstPage = SeekFrame();
/*(void* FirstPageAlloc = (void*)*/ AllocateFrame();
size_t SecondPage = SeekFrame();
/*void* SecondPageAlloc = (void*)*/ AllocateFrame();
if(!(FirstPage == 0 && SecondPage == 1)) {
Passed = false;
SerialPrintf("First iteration: Failed, First page %x, Second page %x.\r\n", FirstPage, SecondPage);
}
FreeFrame(SecondPage);
SecondPage = SeekFrame();
if(SecondPage != 1)
Passed = false;
FreeFrame(FirstPage);
FirstPage = SeekFrame();
if(FirstPage != 0)
Passed = false;
if(Passed)
SerialPrintf("Memory test passed.\r\n");
else {
SerialPrintf("Memory test failed.\r\n");
SerialPrintf("First page %x, Second page %x.\r\n", FirstPage, SecondPage);
}
}

View File

@ -1,4 +1,5 @@
#include <kernel/chroma.h> #include <kernel/chroma.h>
#include <lainlib/lainlib.h>
/************************ /************************
*** Team Kitty, 2020 *** *** Team Kitty, 2020 ***
@ -17,8 +18,39 @@
* There, these functions worked, but here, under BIOS, it's a lot more difficult. * There, these functions worked, but here, under BIOS, it's a lot more difficult.
* It will take some time to get these functions working. * It will take some time to get these functions working.
* *
* The general plan, being that the BOOTBOOT loader has given us static addresses for all of our doodads,
* is to keep the core kernel where it is (FFFFFFFFFFE00000) and load in modules and libraries around it.
*
* We start in the higher half, so we'll dedicate the lower half (7FFFFFFFFFFF and below) to userspace.
*
* That means we have about 3 terabytes of RAM for the kernel.
* This will be identity mapped, always.
*
* Handily, since most modern processors ignore the highest 2 bytes of a virtual address, and the kernel
* is mapped to 0x80000000000 and above, we can use the nomenclature:
* * 0x00007FFFFFFFFFFF and below is user space.
* * 0xFFFF800000000000 and above is kernel space.
* The processor will ignore the first 4 chars, and this provides a great deal of readability for the
* future of the kernel.
*
* We'll have a kernel heap mapped into this kernel space, as well as a kernel stack (for task switching and error tracing).
* These will be 1GB each.
* We may have to increase this in the future, once Helix is fully integrated.
* Helix will take a lot of memory, as it is a fully featured 3D engine. We may have to implement things like
* texture streaming and mipmapping. Minimising RAM usage is NOT a priority for me, but it would be nice
* to have a minimum requirement above 32GB.
*
* // TODO: Expand Kernel Heap
*
*
* //TODO: there are lots of calls to AllocateFrame here, those need to be separated out into AllocateZeroFrame if necessary.
*
*
*/ */
extern size_t _kernel_text_start;
extern size_t _kernel_rodata_start;
extern size_t _kernel_data_start;
//__attribute__((aligned(4096))) static size_t Pagetable[512] = {0}; //__attribute__((aligned(4096))) static size_t Pagetable[512] = {0};
@ -26,317 +58,314 @@
#define SET_ADDRESS(a,b) ((*(size_t*) (a)) = (size_t) b) #define SET_ADDRESS(a,b) ((*(size_t*) (a)) = (size_t) b)
/*
* It turns out it's useful to have macros for the standard
* data size units.
*
* Who would've thoguht?
*/
#define KiB 1 * 1024 #define KiB 1 * 1024
#define MiB 1 * 1024 * KiB #define MiB 1 * 1024 * KiB
#define USERWRITEABLE_FLAGS(a) ((a & 0xFFFFFF00) + 0x83)
#define PAGE_PRESENT 1 #define PAGE_PRESENT 1
#define PAGE_RW 2 #define PAGE_RW 2
#define PAGE_USER 4
#define PAGE_GLOBAL 8
#define USERWRITEABLE_FLAGS(a) ((a & 0xFFFFFF00) + 0x83)
// The AbstractAllocator control struct
static allocator_t Allocator = NULL;
// The AbstractAllocator Ticketlock.
static ticketlock_t AllocatorLock = {0};
// Entries to help allocate the Kernel Stack
static list_entry_t StackFreeList;
static ticketlock_t StackLock = {0};
static void* StackPointer = (void*) KERNEL_STACK_REGION;
// A temporary itoa function for better debugging..
const char* IntToAscii(int In) {
char* OutputBuffer = " ";
size_t Temp, i = 0, j = 0;
do {
Temp = In % 10;
OutputBuffer[i++] = (Temp < 10) ? (Temp + '0') : (Temp + 'a' - 10);
} while (In /= 10);
OutputBuffer[i--] = 0;
for(j = 0; j < i; j++, i--) {
Temp = OutputBuffer[j];
OutputBuffer[j] = OutputBuffer[i];
OutputBuffer[i] = Temp;
}
return OutputBuffer;
}
void InitPaging() { void InitPaging() {
StackFreeList = (list_entry_t) { &StackFreeList, &StackFreeList };
size_t* PML4 = (size_t*) 0xFFA000; // Layer 4 size_t Size = AlignUpwards(AllocatorSize(), PAGE_SIZE);
size_t* PDPE_RAM = (size_t*) 0xFFE000; // Layer 3, contains map for the first 4GB of RAM Allocator = PhysAllocateZeroMem(Size);
size_t* PDE_RAM = (size_t*) 0xFFF000; Allocator = CreateAllocatorWithPool(Allocator, Size);
size_t* PDPE_KERNEL = (size_t*) 0xFFB000; // Layer 3, contains map for the Kernel and everything it needs to run. KernelAddressSpace = (address_space_t) {
size_t* PDE_KERNEL_FB = (size_t*) 0xFFC000; // Layer 2, contains map for the linear framebuffer. .Lock = {0},
.PML4 = PhysAllocateZeroMem(PAGE_SIZE)
};
size_t* PT_KERNEL = (size_t*) 0xFFD000; // Layer 1, the page table for the kernel itself. size_t* Pagetable = KernelAddressSpace.PML4;
size_t fb_ptr = (size_t) &fb; // Identity map the higher half
for(int i = 256; i < 512; i++) {
SET_ADDRESS(PML4, PDPE_RAM); // 3rd Layer entry for RAM Pagetable[i] = (size_t)PhysAllocateZeroMem(PAGE_SIZE);
SET_ADDRESS(PML4 + LAST_ENTRY, PDPE_KERNEL); // 3rd Layer entry for Kernel Pagetable[i] = (size_t)(((char*)Pagetable[i]) - DIRECT_REGION);
Pagetable[i] |= (PAGE_PRESENT | PAGE_RW);
SET_ADDRESS(PDPE_KERNEL + LAST_ENTRY, PDE_KERNEL_FB); // 2nd Layer entry for the framebuffer
// Set the 480th entry (PDE_KERNEL_FB + (480 * 8))
// To the framebuffer + flags
SET_ADDRESS(PDE_KERNEL_FB + 3840, USERWRITEABLE_FLAGS(fb_ptr));
// In 4 byte increments, we're gonna map 3840 (the framebuffer)
// Up to (4096 - 8) in the PDE_KERNEL_FB with 2MB paging.
size_t MappingIterations = 1;
for(size_t i = 3844; i < 4088; i += 4) {
SET_ADDRESS(PDE_KERNEL_FB + i, USERWRITEABLE_FLAGS(fb_ptr) + (MappingIterations * (2 * MiB)));
MappingIterations++;
} }
// Now we map the last entry of PDE_KERNEL_FB to our Page Table MMapEnt* TopEntry = (MMapEnt*)(((&bootldr) + bootldr.size) - sizeof(MMapEnt));
SET_ADDRESS(PDE_KERNEL_FB + LAST_ENTRY, PT_KERNEL); size_t LargestAddress = TopEntry->ptr + TopEntry->size;
// Mapping the kernel into the page tables.... for(size_t Address = 0; Address < AlignUpwards(LargestAddress, PAGE_SIZE); Address += PAGE_SIZE) {
MapVirtualMemory(&KernelAddressSpace, (size_t*)(((char*)Address) + DIRECT_REGION), Address, MAP_WRITE);
SET_ADDRESS(PT_KERNEL, 0xFF8001); // bootldr, bootinfo
SET_ADDRESS(PT_KERNEL + 8, 0xFF9001); // environment
// Map the kernel itself
SET_ADDRESS(PT_KERNEL + 16, KernelAddr + 1);
// Iterate through the pages, identity mapping each one
MappingIterations = 1;
size_t MappingOffset = 0x14;
for(size_t i = 0; i < ((KernelEnd - KernelAddr) >> 12); i++) {
// Page Table + (0x10 increasing by 0x04 each time) = x * 4KiB
SET_ADDRESS(PT_KERNEL + MappingOffset, (MappingIterations * (4 * KiB)));
MappingOffset += 4;
MappingIterations++;
} }
// Now we need to map the core stacks. Top-down, from 0xDFF8 SerialPrintf("Mapping kernel into new memory map.\r\n");
// There's always at least one core, so we do that one fixed.
// TODO: Account for 0-core CPUs //TODO: Disallow execution of rodata and data, and bootldr/environment
SET_ADDRESS(PT_KERNEL + LAST_ENTRY, 0xF14003); for(void* Address = CAST(void*, KERNEL_REGION);
MappingIterations = 1; Address < CAST(void*, KERNEL_REGION + 0x2000); // Lower half of Kernel
// For every core: Address = CAST(void*, CAST(char*, Address) + PAGE_SIZE)) {
for(size_t i = 0; i < (bootldr.numcores + 3U) >> 2; i++) { MapVirtualMemory(&KernelAddressSpace, Address, (CAST(size_t, Address) - KERNEL_REGION) + KERNEL_PHYSICAL, MAP_EXEC);
// PT_KERNEL[512 - (iterations + 1)] = 0x14003 + (iterations * page-width)
SET_ADDRESS(PT_KERNEL + LAST_ENTRY - (MappingIterations * 8), 0xF14003 + (4096 * MappingIterations));
MappingIterations++;
} }
SET_ADDRESS(PDPE_RAM, PDE_RAM + PAGE_PRESENT + PAGE_RW); for(void* Address = CAST(void*, KERNEL_REGION + 0x2000);
SET_ADDRESS(PDPE_RAM + 8, 0xF10000 + PAGE_PRESENT + PAGE_RW); Address < CAST(void*, KERNEL_REGION + 0x12000); // Higher half of kernel
SET_ADDRESS(PDPE_RAM + 16, 0xF11000 + PAGE_PRESENT + PAGE_RW); Address = CAST(void*, CAST(char*, Address) + PAGE_SIZE)) {
SET_ADDRESS(PDPE_RAM + 24, 0xF12000 + PAGE_PRESENT + PAGE_RW); MapVirtualMemory(&KernelAddressSpace, Address, (CAST(size_t, Address) - KERNEL_REGION) + KERNEL_PHYSICAL_2, MAP_EXEC);
// Identity map 4GB of ram
// Each page table can only hold 512 entries, but we
// just set up 4 of them - overflowing PDE_RAM (0xF000)
// will take us into 0x10000, into 0x11000, into 0x120000.
for(size_t i = 0; i < 512 * 4/*GB*/; i++) {
// add PDE_RAM, 4
// mov eax, 0x83
// add eax, 2*1024*1024
SET_ADDRESS(PDE_RAM + (i * 4), USERWRITEABLE_FLAGS(i * (2 * MiB)));
} }
// Map first 2MB of memory for(void* Address = CAST(void*, FB_REGION);
SET_ADDRESS(PDE_RAM, 0xF13000 + PAGE_PRESENT + PAGE_RW); Address < CAST(void*, 0x200000); // TODO: Turn this into a calculation with bootldr.fb_size
Address = CAST(void*, CAST(char*, Address) + PAGE_SIZE)) {
for(size_t i = 0; i < 512; i++) { MapVirtualMemory(&KernelAddressSpace, Address, (CAST(size_t, Address) - FB_REGION) + FB_PHYSICAL, MAP_WRITE);
SET_ADDRESS(0xF13000 + i * 4, i * (4 * KiB) + PAGE_PRESENT + PAGE_RW);
} }
// 0xA000 should now contain our memory map. SerialPrintf("Kernel mapped into pagetables. New PML4 at 0x%p\r\n", KernelAddressSpace.PML4);
//ASSERT(Allocator != NULL);
}
static size_t GetCachingAttribute(pagecache_t Cache) {
switch (Cache) {
case CACHE_WRITE_BACK: return 0;
case CACHE_WRITE_THROUGH: return 1 << 2;
case CACHE_NONE: return 1 << 3;
case CACHE_WRITE_COMBINING: return 1 << 6;
}
return 1 << 3;
}
static bool ExpandAllocator(size_t NewSize) {
size_t AllocSize = AlignUpwards(AllocatorPoolOverhead() + sizeof(size_t) * 5 + NewSize, PAGE_SIZE);
void* Pool = PhysAllocateMem(AllocSize);
return AddPoolToAllocator(Allocator, Pool, AllocSize) != NULL;
}
static void GetPageFromTables(address_space_t* AddressSpace, size_t VirtualAddress, size_t** Page) {
//ASSERT(Page != NULL);
//ASSERT(AddressSpace != NULL);
size_t* Pagetable = AddressSpace->PML4;
for(int Level = 4; Level > 1; Level--) {
size_t* Entry = &Pagetable[(VirtualAddress >> (12u + 9u * (Level - 1))) & 0x1FFU];
ASSERT(*Entry & PAGE_PRESENT, "Page not present during retrieval");
Pagetable = (size_t*)((char*)(*Entry & 0x7ffffffffffff000ull) + DIRECT_REGION);
}
ASSERT(Pagetable[(VirtualAddress >> 12U) & 0x1FFU] & PAGE_PRESENT, "PDPE not present during retrieval");
*Page = &Pagetable[(VirtualAddress >> 12U) & 0x1FFU];
} }
void SetAddressSpace(address_space_t* AddressSpace) {
//ASSERT(AddressSpace != NULL);
void InitPagingOldImpl() { if((size_t)((char*)ReadControlRegister(3) + DIRECT_REGION) != (size_t) &AddressSpace->PML4) {
WriteControlRegister(3, CAST(size_t, &AddressSpace->PML4));
// Disable paging so that we can work with the pagetable }
//size_t registerTemp = ReadControlRegister(0);
//UNSET_PGBIT(registerTemp);
//WriteControlRegister(0, registerTemp);
// Clear space for our pagetable
size_t PagetableDest = 0x1000;
memset((char*)PagetableDest, 0, 4096);
// Start setting pagetable indexes
*((size_t*)PagetableDest) = 0x2003; // PDP at 0x2000, present & r/w
*((size_t*)PagetableDest + 0x1000) = 0x3003; // PDT at 0x3000, present & r/w
*((size_t*)PagetableDest + 0x2000) = 0x4003; // PT at 0x4000, present & r/w
size_t value = 0x3;
size_t offset = 8;
for(size_t i = 0; i < 512; i++) { // 512 iterations (entries into the page table)
*((size_t*) PagetableDest + offset) = value; // We're setting 512 bytes with x003
// (identity mapping the first 4 megabytes of memory)
// (mapping the page table to itself)
value += 4096; // Point to start of next page
offset += 8; // + 8 bytes (next entry in list)
} }
// Enable PAE paging void MapVirtualMemory(address_space_t* AddressSpace, void* VirtualAddress, size_t PhysicalAddress, mapflags_t Flag) {
size_t reg = ReadControlRegister(4);
SET_PAEBIT(reg);
WriteControlRegister(4, reg);
WriteControlRegister(3, PagetableDest); //bool MapGlobally = false;
size_t Virtual = (size_t)VirtualAddress;
//ASSERT(AddressSpace != NULL);
TicketAttemptLock(&AddressSpace->Lock);
size_t Flags = PAGE_PRESENT;
if(Flag & MAP_WRITE)
Flags |= MAP_WRITE;
if(Virtual < USER_REGION)
Flags |= PAGE_USER;
//TODO: Global mapping
size_t* Pagetable = AddressSpace->PML4;
for(int Level = 4; Level > 1; Level--) {
size_t* Entry = &Pagetable[(Virtual >> (12u + 9u * (Level - 1))) & 0x1FFu];
if(!(*Entry & PAGE_PRESENT)) {
directptr_t Pointer = PhysAllocateZeroMem(PAGE_SIZE);
*Entry = (size_t)(((char*)Pointer) + DIRECT_REGION);
}
*Entry |= Flags;
Pagetable = (size_t*)(((char*)(*Entry & 0x7ffffffffffff000ull) + DIRECT_REGION));
}
size_t* Entry = &Pagetable[(Virtual >> 12u) & 0x1FFu];
*Entry = Flags | PhysicalAddress;
if(AddressSpace != NULL) {
TicketUnlock(&AddressSpace->Lock);
}
} }
void UnmapVirtualMemory(address_space_t* AddressSpace, void* VirtualAddress){
//ASSERT(AddressSpace != NULL);
/* size_t registerTemp = ReadControlRegister(4); TicketAttemptLock(&AddressSpace->Lock);
if(registerTemp & (1 << 7)) {
TOGGLE_PGEBIT(registerTemp); size_t* Entry;
WriteControlRegister(4, registerTemp); GetPageFromTables(AddressSpace, (size_t)VirtualAddress, &Entry);
*Entry = 0;
InvalidatePage((size_t)VirtualAddress);
if(AddressSpace != NULL) {
TicketUnlock(&AddressSpace->Lock);
} }
if(registerTemp & (1 << 7))
WriteControlRegister(4, registerTemp ^ (1 << 7));
size_t CPUIDReturn;
asm volatile("cpuid" : "=d" (CPUIDReturn) : "a" (0x80000001) : "%rbx", "%rcx");
if(CPUIDReturn & (1 << 26)) {
SerialPrintf("System supports 1GB pages.\r\n");
if(registerTemp & (1 << 12)) {
SerialPrintf("PML5 paging available - using that instead.\r\n");
if(MemorySize > (1ULL << 57))
SerialPrintf("System has over 128Petabytes of RAM. Please consider upgrading the OS on your supercomputer.\r\n");
size_t MaxPML5 = 1;
size_t MaxPML4 = 1;
size_t MaxPDP = 512;
size_t LastPML4Entry = 512;
size_t LastPDPEntry = 512;
size_t MemorySearchDepth = MemorySize;
while(MemorySearchDepth > (256ULL << 30)) {
MaxPML5++;
MemorySearchDepth -= (256ULL << 30);
}
if(MaxPML5 > 512)
MaxPML5 = 512;
if(MemorySearchDepth) {
LastPDPEntry = ( (MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30;
if(MaxPML5 > 512)
MaxPML5 = 512;
} }
size_t PML4Size = PAGETABLE_SIZE * MaxPML5; void CacheVirtualMemory(address_space_t* AddressSpace, void* VirtualAddress, pagecache_t Cache) {
size_t PDPSize = PML4Size * MaxPML4;
size_t PML4Base = AllocatePagetable(PML4Size + PDPSize); //ASSERT(AddressSpace != NULL);
size_t PDPBase = PML4Base + PML4Size;
for(size_t PML5Entry = 0; PML5Entry < MaxPML5; PML5Entry++) { TicketAttemptLock(&AddressSpace->Lock);
Pagetable[PML5Entry] = PML4Base + (PML5Entry << 12);
if(PML5Entry == (MaxPML5 - 1)) size_t* Entry;
MaxPML4 = LastPML4Entry;
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) { GetPageFromTables(AddressSpace, (size_t)VirtualAddress, &Entry);
((size_t*) Pagetable[PML5Entry])[PML4Entry] = PDPBase + (((PML5Entry << 9) + PML5Entry) << 12); *Entry &= ~((1 << 6) | (1 << 2) | (1 << 3));
*Entry |= GetCachingAttribute(Cache);
if( (PML5Entry == (MaxPML5 - 1)) && (PML4Entry == (MaxPML4 -1)) ) InvalidatePage((size_t)VirtualAddress);
MaxPDP = LastPDPEntry;
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) { if(AddressSpace != NULL) {
((size_t* ) ((size_t* ) Pagetable[PML5Entry])[PML4Entry])[PDPEntry] = ( ((PML5Entry << 18) + (PML4Entry << 9) + PDPEntry) << 30) | (0x83); TicketUnlock(&AddressSpace->Lock);
}
} }
((size_t* ) Pagetable[PML5Entry])[PML4Entry] |= 0x3;
void* AllocateMemory(size_t Bits) {
TicketAttemptLock(&AllocatorLock);
void* Result = AllocatorMalloc(Allocator, Bits);
if(Result == NULL) {
if(!ExpandAllocator(Bits)) {
TicketUnlock(&AllocatorLock);
return 0ULL;
} }
Pagetable[PML5Entry] |= 0x3; Result = AllocatorMalloc(Allocator, Bits);
}
if(Result != NULL) {
memset(Result, 0, Bits);
}
TicketUnlock(&AllocatorLock);
return Result;
}
void* ReallocateMemory(void* Address, size_t NewSize) {
TicketAttemptLock(&AllocatorLock);
void* Result = AllocatorRealloc(Allocator, Address, NewSize);
if(Result == NULL) {
if(!ExpandAllocator(NewSize)) {
TicketUnlock(&AllocatorLock);
return 0ULL;
}
Result = AllocatorRealloc(Allocator, Address, NewSize);
}
TicketUnlock(&AllocatorLock);
return Result;
}
void FreeMemory(void* Address) {
TicketAttemptLock(&AllocatorLock);
AllocatorFree(Allocator, Address);
TicketUnlock(&AllocatorLock);
}
void* AllocateKernelStack() {
void* StackAddress = NULL;
size_t StackSize = PAGE_SIZE * 4;
TicketAttemptLock(&StackLock);
if(ListIsEmpty(&StackFreeList)) {
StackAddress = StackPointer;
StackPointer = (void*)(((char*)StackPointer) + (4*KiB) + StackSize);
for(size_t i = 0; i < (StackSize / PAGE_SIZE); i++) {
directptr_t NewStack;
NewStack = PhysAllocateZeroMem(PAGE_SIZE);
MapVirtualMemory(&KernelAddressSpace, (void*)((size_t)StackAddress + i * PAGE_SIZE), (size_t)((char*)NewStack) - DIRECT_REGION, MAP_WRITE);
} }
} else { } else {
SerialPrintf("PML4 available - using that instead.\r\n"); list_entry_t* StackEntry = StackFreeList.Next;
size_t MemorySearchDepth = MemorySize; ListRemove(StackEntry);
memset(StackEntry, 0, StackSize);
if(MemorySearchDepth > (1ULL << 48)) StackAddress = (void*)StackEntry;
SerialPrintf("RAM limited to 256TB.\r\n");
size_t MaxPML4 = 1;
size_t MaxPDP = 512;
size_t LastPDPEntry = 512;
while(MemorySearchDepth > (512ULL << 30)) {
MaxPML4++;
MemorySearchDepth -= (512ULL << 30);
} }
if(MaxPML4 > 512) TicketUnlock(&StackLock);
MaxPML4 = 512;
if(MemorySearchDepth) { StackAddress = (void*)((size_t)StackAddress + StackSize);
LastPDPEntry = ( (MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30; StackAddress = (void*)((size_t)StackAddress - sizeof(size_t) * 2);
if(LastPDPEntry > 512) return StackAddress;
LastPDPEntry = 512;
} }
size_t PDPSize = PAGETABLE_SIZE * MaxPML4; void FreeKernelStack(void* StackAddress) {
size_t PDPBase = AllocatePagetable(PDPSize); TicketAttemptLock(&StackLock);
list_entry_t* ListEntry = (list_entry_t*)(((size_t)(StackAddress) + (sizeof(size_t) * 2)) - (PAGE_SIZE * 4));
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) { ListAdd(&StackFreeList, ListEntry);
Pagetable[PML4Entry] = PDPBase + (PML4Entry << 12); TicketUnlock(&StackLock);
if(PML4Entry == (MaxPML4 - 1)) {
MaxPDP = LastPDPEntry;
} }
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) {
((size_t* ) Pagetable[PML4Entry])[PDPEntry] = (((PML4Entry << 9) + PDPEntry) << 30) | 0x83;
}
Pagetable[PML4Entry] |= 0x3;
}
}
} else {
SerialPrintf("System does not support 1GB pages - using 2MiB paging instead.\r\n");
size_t MemorySearchDepth = MemorySize;
if(MemorySearchDepth > (1ULL << 48)) {
SerialPrintf("Usable RAM is limited to 256TB, and the page table alone will use 1GB of space in memory.\r\n");
}
size_t MaxPML4 = 1, MaxPDP = 512, MaxPD = 512, LastPDPEntry = 1;
while(MemorySearchDepth > (512ULL << 30)) {
MaxPML4++;
MemorySearchDepth -= (512ULL << 30);
}
if(MaxPML4 > 512)
MaxPML4 = 512;
if(MemorySearchDepth) {
LastPDPEntry = ((MemorySearchDepth + ((1 << 30) - 1)) & (~0ULL << 30)) >> 30;
if(LastPDPEntry > 512)
LastPDPEntry = 512;
}
size_t PDPSize = PAGETABLE_SIZE * MaxPML4;
size_t PDSize = PDPSize * MaxPDP;
size_t PDPBase = AllocatePagetable(PDPSize + PDSize);
size_t PDBase = PDPBase + PDSize;
for(size_t PML4Entry = 0; PML4Entry < MaxPML4; PML4Entry++) {
Pagetable[PML4Entry] = PDBase + (PML4Entry << 12);
if(PML4Entry == (MaxPML4 - 1)) {
MaxPDP = LastPDPEntry;
}
for(size_t PDPEntry = 0; PDPEntry < MaxPDP; PDPEntry++) {
( (size_t* ) Pagetable[PML4Entry])[PDPEntry] = PDBase + (((PML4Entry << 9) + PDPEntry) << 12);
for(size_t PDEntry = 0; PDEntry < MaxPD; PDEntry++) {
( (size_t* ) ((size_t*) Pagetable[PML4Entry])[PDPEntry])[PDEntry] = (( (PML4Entry << 18) + (PDPEntry << 9) + PDPEntry) << 21) | 0x83;
}
( (size_t* ) Pagetable[PML4Entry])[PDPEntry] |= 0x3;
}
Pagetable[PML4Entry] |= 0x3;
}
}
WriteControlRegister(3, Pagetable);
registerTemp = ReadControlRegister(4);
if(!(registerTemp & (1 << 7))) {
TOGGLE_PGEBIT(registerTemp);
WriteControlRegister(4, registerTemp);
}*/

View File

@ -1,5 +1,6 @@
#include <kernel/chroma.h> #include <kernel/chroma.h>
#include <kernel/system/heap.h> #include <kernel/system/heap.h>
#include <lainlib/lainlib.h>
/************************ /************************
*** Team Kitty, 2020 *** *** Team Kitty, 2020 ***
@ -22,10 +23,144 @@
*/ */
#define MIN_ORDER 3
#define PEEK(type, address) (*((volatile type*)(address)))
uint8_t* Memory = ((uint8_t*)(&end)); uint8_t* Memory = ((uint8_t*)(&end));
uint8_t* MemoryStart; uint8_t* MemoryStart;
size_t MemoryBuckets; size_t MemoryBuckets;
static buddy_t LowBuddy = {
.MaxOrder = 32,
.Base = (directptr_t) DIRECT_REGION,
.List = (directptr_t[32 - MIN_ORDER]) {0},
.Lock = {0},
};
static buddy_t HighBuddy = {
.MaxOrder = 64,
.Base = 0,
.List = (directptr_t[64 - MIN_ORDER]) {0},
.Lock = {0},
};
static size_t MemoryLength;
static bool CheckBuddies(buddy_t* Buddy, directptr_t InputA, directptr_t InputB, size_t Size) {
size_t LowerBuddy = MIN(CAST(size_t, InputA), CAST(size_t, InputB)) - (size_t) Buddy->Base;
size_t HigherBuddy = MAX(CAST(size_t, InputA), CAST(size_t, InputB)) - (size_t) Buddy->Base;
return (LowerBuddy ^ Size) == HigherBuddy;
}
static void AddToBuddyList(buddy_t* Buddy, directptr_t Address, size_t Order, bool NewEntry) {
directptr_t ListHead = Buddy->List[Order - MIN_ORDER];
//SerialPrintf("Adding new entry to buddy: Address 0x%p with order %d, New Entry is %s\r\n", Address, Order, NewEntry ? "true" : "false");
/*
SerialPrintf("About to poke memory..\r\n");
PEEK(directptr_t, Address) = 0;
SerialPrintf("Did it work?\r\n");
*/
size_t Size = 1ull << Order;
TicketAttemptLock(&Buddy->Lock);
//SerialPrintf("Ticketlock engaged\r\n");
if(!NewEntry && ListHead != 0) {
directptr_t ListPrevious = 0;
while(true) {
if(CheckBuddies(Buddy, ListHead, Address, Size)) {
if(ListPrevious != 0) {
PEEK(directptr_t, ListPrevious) = PEEK(directptr_t, ListHead);
} else
Buddy->List[Order - MIN_ORDER] = PEEK(directptr_t, ListHead);
AddToBuddyList(Buddy, MIN(ListHead, Address), Order + 1, false);
break;
}
if(PEEK(directptr_t, ListHead) == 0) {
PEEK(directptr_t, ListHead) = Address;
break;
}
ListPrevious = ListHead;
ListHead = PEEK(directptr_t, ListHead);
}
} else {
//SerialPrintf("\tAbout to poke memory 0x%p - current value is 0x%x\r\n", Address, *((size_t*)(Address)));
*((size_t*)(Address)) = (size_t) ListHead;
Buddy->List[Order - MIN_ORDER] = Address;
}
TicketUnlock(&Buddy->Lock);
//SerialPrintf("Ticketlock Released.\r\n");
}
static void AddRangeToBuddy(buddy_t* Buddy, directptr_t Base, size_t Size) {
//SerialPrintf("Starting a new range addition.\r\n\t");
while(Size > (1ull << MIN_ORDER)) {
//SerialPrintf("New iteration. Current Size: 0x%x\r\n\t", Size);
for(int Order = Buddy->MaxOrder - 1; Order >= MIN_ORDER; Order--) {
//SerialPrintf("New Loop. Current Order: %d\r\n\t", Order);
if(Size >= (1ull << Order)) {
//SerialPrintf("\tNew loop check passed.\r\n\t");
AddToBuddyList(Buddy, Base, Order, true);
//SerialPrintf("\tEntry added to current buddy. Moving onto memory operations..\r\n\t");
Base = (void*)((((char*)Base) + (1ull << Order)));
Size -= 1ull << Order;
//SerialPrintf("\tMemory operations complete. Moving onto next iteration.\r\n");
break;
}
}
}
}
static directptr_t BuddyAllocate(buddy_t* Buddy, size_t Size) {
int InitialOrder = MAX((64 - CLZ(Size - 1)), MIN_ORDER);
size_t WantedSize = 1ull << InitialOrder;
if(InitialOrder >= Buddy->MaxOrder) {
SerialPrintf("Tried to allocate too much physical memory for buddy 0x%p\r\n", Buddy);
SerialPrintf("Buddy 0x%p has max order %d, but 0x%x bytes was requested.\r\nInitial Order: %d, Wanted Size: 0x%x\r\n", Buddy, Buddy->MaxOrder, Size, InitialOrder, WantedSize);
return NULL;
}
TicketAttemptLock(&Buddy->Lock);
SerialPrintf("Searching for a valid order to allocate into. Condition: {\r\n\tOrder: %d,\r\n\tSize: 0x%x\r\n}\r\n\n", InitialOrder, WantedSize);
for(int Order = InitialOrder; Order < Buddy->MaxOrder; Order++) {
SerialPrintf("\tCurrent Order: %d, Buddy entry: %x\r\n", Order, Buddy->List[Order - MIN_ORDER]);
if(Buddy->List[Order - MIN_ORDER] != 0) {
SerialPrintf("\t\tFound a valid Order!\r\n");
directptr_t Address = Buddy->List[Order - MIN_ORDER];
Buddy->List[Order - MIN_ORDER] = PEEK(directptr_t, Address);
TicketUnlock(&Buddy->Lock);
size_t FoundSize = 1ull << Order;
SerialPrintf("\t\tAdding area - Address 0x%p, Size 0x%x\r\n\n", Address, FoundSize);
AddRangeToBuddy(Buddy, (void*)((size_t)Address + WantedSize), FoundSize - WantedSize);
SerialPrintf("\t\tArea added!\r\n\n");
return Address;
}
}
SerialPrintf("BuddyAllocate: Unable to find a valid order to allocate!\r\nInitial Order: %d, WantedSize: 0x%x\r\n\r\n", InitialOrder, WantedSize);
TicketUnlock(&Buddy->Lock);
return NULL;
}
void InitMemoryManager() { void InitMemoryManager() {
@ -77,7 +212,7 @@ void ListMemoryMap() {
for(MMapEnt* MapEntry = &bootldr.mmap; (size_t)MapEntry < (size_t)&environment; MapEntry++) { for(MMapEnt* MapEntry = &bootldr.mmap; (size_t)MapEntry < (size_t)&bootldr + bootldr.size; MapEntry++) {
char EntryType[8] = {0}; char EntryType[8] = {0};
switch(MMapEnt_Type(MapEntry)) { switch(MMapEnt_Type(MapEntry)) {
case MMAP_FREE: case MMAP_FREE:
@ -101,60 +236,99 @@ void ListMemoryMap() {
if(entry_from != 0 && entry_to != 0) if(entry_from != 0 && entry_to != 0)
SerialPrintf("[ mem 0x%p-0x%p] %s\r\n", entry_from, entry_to, EntryType); SerialPrintf("[ mem 0x%p-0x%p] %s\r\n", entry_from, entry_to, EntryType);
if(MMapEnt_Type(MapEntry) == MMAP_FREE) {
SerialPrintf("\tAdding this entry to the physical memory manager!\r\n");
AddRangeToPhysMem((void*)((char*)(MMapEnt_Ptr(MapEntry) /* + DIRECT_REGION*/ )), MMapEnt_Size(MapEntry));
}
} }
} }
size_t AllocateFrame() { void AddRangeToPhysMem(directptr_t Base, size_t Size) {
size_t FreePage = SeekFrame(); if(Base < (void*)(LOWER_REGION + DIRECT_REGION)) {
SET_BIT(FreePage); SerialPrintf("New range in lower memory: 0x%p, size 0x%x\r\n", Base, Size);
return FreePage; AddRangeToBuddy(&LowBuddy, Base, Size);
} else {
if(HighBuddy.Base == NULL) {
HighBuddy.Base = Base;
} }
void FreeFrame(size_t Frame) { AddRangeToBuddy(&HighBuddy, Base, Size);
UNSET_BIT(Frame);
} }
size_t SeekFrame() { if(MemoryLength < AlignUpwards((size_t)Base + Size, PAGE_SIZE) / PAGE_SIZE) {
for(size_t i = 0; i < MemoryPages; i++) { MemoryLength = AlignUpwards((size_t)Base + Size, PAGE_SIZE) / PAGE_SIZE;
if(!READ_BIT(i)) }
return i;
} }
SerialPrintf("Memory manager: Critical!\r\n"); directptr_t PhysAllocateLowMem(size_t Size) {
return (size_t) -1; directptr_t Pointer = BuddyAllocate(&LowBuddy, Size);
ASSERT(Pointer != NULL, "PhysAllocateLowMem: Allocation failed!");
return Pointer;
} }
void MemoryTest() { directptr_t PhysAllocateMem(size_t Size) {
SerialPrintf("Initializing basic memory test..\r\n"); directptr_t Pointer = NULL;
bool Passed = true;
size_t FirstPage = SeekFrame();
/*(void* FirstPageAlloc = (void*)*/ AllocateFrame();
size_t SecondPage = SeekFrame();
/*void* SecondPageAlloc = (void*)*/ AllocateFrame();
if(!(FirstPage == 0 && SecondPage == 1)) { if(HighBuddy.Base == 0)
Passed = false; Pointer = BuddyAllocate(&HighBuddy, Size);
SerialPrintf("First iteration: Failed, First page %x, Second page %x.\r\n", FirstPage, SecondPage);
if(Pointer == NULL)
Pointer = BuddyAllocate(&LowBuddy, Size);
ASSERT(Pointer != NULL, "PhysAllocateMem: Unable to allocate memory!");
return Pointer;
} }
FreeFrame(SecondPage); directptr_t PhysAllocateZeroMem(size_t Size) {
SecondPage = SeekFrame(); directptr_t Pointer = PhysAllocateMem(Size);
memset(Pointer, 0, Size);
return Pointer;
}
if(SecondPage != 1) directptr_t PhysAllocateLowZeroMem(size_t Size) {
Passed = false; directptr_t Pointer = PhysAllocateLowMem(Size);
memset(Pointer, 0, Size);
return Pointer;
FreeFrame(FirstPage); }
FirstPage = SeekFrame();
if(FirstPage != 0) void PhysFreeMem(directptr_t Pointer, size_t Size) {
Passed = false; ASSERT(Pointer >= (directptr_t) DIRECT_REGION, "PhysFreeMem: Attempting to free memory not in the direct mapping region.");
if(Passed) buddy_t* Buddy;
SerialPrintf("Memory test passed.\r\n");
else { if(Pointer < (void*)(LOWER_REGION + DIRECT_REGION))
SerialPrintf("Memory test failed.\r\n"); Buddy = &LowBuddy;
SerialPrintf("First page %x, Second page %x.\r\n", FirstPage, SecondPage); else
Buddy = &HighBuddy;
int Order = MAX(64 - CLZ(Size - 1), MIN_ORDER);
AddToBuddyList(Buddy, Pointer, Order, false);
}
static _Atomic(uint16_t)* PageRefCount = NULL;
void PhysAllocatorInit() {
PageRefCount = PhysAllocateZeroMem(sizeof(uint16_t) * MemoryPages);
}
directptr_t PhysAllocatePage() {
directptr_t Page = PhysAllocateMem(PAGE_SIZE);
PhysRefPage(Page);
return Page;
}
void PhysRefPage(directptr_t Page) {
PageRefCount[(size_t) Page >> PAGE_SHIFT]++;
}
void PhysFreePage(directptr_t Page) {
if(--PageRefCount[(size_t)Page >> PAGE_SHIFT] == 0) {
PhysFreeMem(Page, PAGE_SIZE);
} }
} }