Espresso 0.0.2a

This commit is contained in:
2025-10-20 21:57:30 -05:00
parent 102d517097
commit ff6cba1164
59 changed files with 29272 additions and 773 deletions

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@ -1,76 +1,138 @@
#include <stdio.h>
#include <string.h>
#include <mm/heap.h>
#include <mm/pmm.h>
#include <mm/paging.h>
#include <string.h>
#include <stdio.h>
#include <mm_macros.h>
#include <mm/heap.h>
#define ALIGNMENT 8
#define ALIGN(size) (((size) + (ALIGNMENT - 1)) & ~(ALIGNMENT - 1))
#define ALIGN4(x) (((x) + 3) & ~3)
#define MIN_BLOCK_SIZE 16
typedef struct block_header {
typedef struct block {
size_t size;
struct block_header* next;
struct block* next;
int free;
} block_header_t;
} block_t;
#define BLOCK_SIZE sizeof(block_header_t)
#define BLOCK_SIZE sizeof(block_t)
static uint8_t* heap_base = (uint8_t*)HEAP_START;
static uint8_t* heap_end = (uint8_t*)(HEAP_START + HEAP_SIZE);
static uint8_t* heap_base;
static uint8_t* heap_end;
static size_t heap_size;
static block_t* free_list;
static block_header_t* free_list = NULL;
void heap_init(void)
void heap_init(uint32_t start, uint32_t size)
{
free_list = (block_header_t*)heap_base;
free_list->size = HEAP_SIZE - BLOCK_SIZE;
free_list->next = NULL;
#ifdef _DEBUG
printf("[ HEAP ] Initializing heap allocator...\n");
#endif
heap_base = (uint8_t*) ALIGN4((uintptr_t) start);
heap_end = heap_base;
heap_size = size;
free_list = NULL;
for (uint32_t i = 0; i < size; i += 0x1000)
{
map_page(pmm_alloc_page(), (void*)(start + i));
}
/* Set up initial free block */
free_list = (block_t*)heap_base;
free_list->size = heap_size - BLOCK_SIZE;
free_list->free = 1;
free_list->next = NULL;
heap_end = heap_base + size;
#ifdef _DEBUG
printf("[ HEAP ] Heap allocator initialized\n");
#endif
}
void* malloc(size_t size)
static block_t* find_free_block(size_t size)
{
size = ALIGN(size);
block_header_t* curr = free_list;
block_t* curr = free_list;
while (curr)
{
if (curr->free && curr->size >= size)
{
/* Split if there's space for another block */
if (curr->size >= size + BLOCK_SIZE + ALIGNMENT)
{
block_header_t* new_block = (block_header_t*)((uint8_t*)curr + BLOCK_SIZE + size);
new_block->size = curr->size - size - BLOCK_SIZE;
new_block->next = curr->next;
new_block->free = 1;
curr->next = new_block;
curr->size = size;
}
curr->free = 0;
return (void*)((uint8_t*)curr + BLOCK_SIZE);
return curr;
}
curr = curr->next;
}
printd("Malloc failed due to lack of free memory\n");
printf("find_free_block(): No free block found!\n");
return NULL;
}
static void split_block(block_t* blk, size_t size)
{
if (blk->size >= size + BLOCK_SIZE + MIN_BLOCK_SIZE)
{
block_t* new_blk = (block_t*)((uint8_t*)blk + BLOCK_SIZE + size);
new_blk->size = blk->size - size - BLOCK_SIZE;
new_blk->free = 1;
new_blk->next = blk->next;
blk->next = new_blk;
blk->size = size;
}
}
void* malloc(size_t size)
{
size = ALIGN4(size);
block_t* blk = find_free_block(size);
if (!blk)
{
printf("malloc(): No free block found!\n");
return NULL;
}
split_block(blk, size);
blk->free = 0;
return (void*)((uint8_t*)blk + BLOCK_SIZE);
}
void free(void* ptr)
{
if (!ptr)
{
return;
}
block_t* blk = (block_t*)((uint8_t*)ptr - BLOCK_SIZE);
blk->free = 1;
/* coalesce */
block_t* curr = free_list;
while (curr && curr->next)
{
if (curr->free && curr->next->free)
{
curr->size += BLOCK_SIZE + curr->next->size;
curr->next = curr->next->next;
}
else
{
curr = curr->next;
}
}
}
void* calloc(size_t nmemb, size_t size)
{
size_t total = nmemb * size;
void* ptr = malloc(total);
if (ptr)
{
memset(ptr, 0, total);
MEMSET(ptr, 0, total);
}
return ptr;
}
@ -81,57 +143,25 @@ void* realloc(void* ptr, size_t size)
return malloc(size);
}
if (size == 0)
if (!size)
{
free(ptr);
return NULL;
}
block_header_t* block = (block_header_t*)((uint8_t*)ptr - BLOCK_SIZE);
if (block->size >= size)
block_t* blk = (block_t*)((uint8_t*)ptr - BLOCK_SIZE);
if (blk->size >= size)
{
return ptr;
}
void* new_ptr = malloc(size);
if (new_ptr) {
memcpy(new_ptr, ptr, block->size);
if (new_ptr)
{
memcpy(new_ptr, ptr, blk->size);
free(ptr);
}
return new_ptr;
}
void free(void* ptr)
{
if (!ptr)
{
return;
}
block_header_t* block = (block_header_t*)((uint8_t*)ptr - BLOCK_SIZE);
block->free = 1;
/* Forward coalescing */
if (block->next && block->next->free)
{
block->size += BLOCK_SIZE + block->next->size;
block->next = block->next->next;
}
/* Backward coalescing */
block_header_t* prev = NULL;
block_header_t* curr = free_list;
while (curr && curr != block)
{
prev = curr;
curr = curr->next;
}
if (prev && prev->free)
{
prev->size += BLOCK_SIZE + block->size;
prev->next = block->next;
}
}

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@ -1,82 +1,60 @@
#include <mm/pmm.h>
#include <string.h>
#include <mm_macros.h>
#include <stdio.h>
#include <mm/paging.h>
#include <mm/pmm.h>
#include <mm/heap.h>
#define PAGE_DIRECTORY_ENTRIES 1024
#define PAGE_TABLE_ENTRIES 1024
#define PAGE_SIZE 4096
#define PAGE_PRESENT 0x1
#define PAGE_WRITE 0x2
#define PAGE_SIZE 4096
typedef uint32_t page_directory_entry_t;
typedef uint32_t page_table_entry_t;
static page_directory_entry_t* page_directory = NULL; /* Will be allocated */
static page_table_entry_t* page_tables[PAGE_DIRECTORY_ENTRIES];
extern void _enable_paging_asm(void);
void paging_init(void)
{
/* Allocate and clear the page directory */
page_directory = (page_directory_entry_t*)alloc_page();
memset(page_directory, 0, PAGE_SIZE);
/* Allocate and set up the first identity-mapped page table (0-4MB) */
page_tables[0] = (page_table_entry_t*)alloc_page();
memset(page_tables[0], 0, PAGE_SIZE);
for (uint32_t i = 0; i < PAGE_TABLE_ENTRIES; i++)
{
page_tables[0][i] = (i * PAGE_SIZE) | 3; /* Present | RW */
}
page_directory[0] = ((uint32_t)page_tables[0]) | 3;
/* Allocate and clear the heap page table */
uint32_t heap_pd_index = HEAP_START >> 22; /* 0xC0000000 >> 22 = 768 */
page_tables[heap_pd_index] = (page_table_entry_t*)alloc_page();
memset(page_tables[heap_pd_index], 0, PAGE_SIZE);
/* Map 4MB heap pages */
for (uint32_t i = 0; i < PAGE_TABLE_ENTRIES; i++) /* 1024 pages = 4MB */
{
void* phys = alloc_page();
if (phys == 0)
{
printf("Out of physical memory during heap mapping!\n");
while (1);
}
page_tables[heap_pd_index][i] = ((uint32_t)phys & 0xFFFFF000) | 3; /* Present | RW */
}
page_directory[heap_pd_index] = ((uint32_t)page_tables[heap_pd_index]) | 3;
/* Load page directory */
asm volatile ("mov %0, %%cr3" : : "r"(page_directory));
/* Enable paging */
_enable_paging_asm();
}
static uint32_t* page_directory;
void map_page(void* phys_addr, void* virt_addr)
{
uint32_t pd_index = ((uint32_t)virt_addr >> 22) & 0x3FF;
uint32_t pt_index = ((uint32_t)virt_addr >> 12) & 0x3FF;
uint32_t pd_idx = ((uint32_t)virt_addr >> 22) & 0x3FF;
uint32_t pt_idx = ((uint32_t)virt_addr >> 12) & 0x3FF;
/* Allocate page table if necessary */
if (!(page_directory[pd_index] & 1))
uint32_t* page_table;
if (!(page_directory[pd_idx] & PAGE_PRESENT))
{
void* pt_phys = alloc_page();
page_tables[pd_index] = (page_table_entry_t*)((uint32_t)pt_phys + 0xC0000000); /* Map it higher */
memset(page_tables[pd_index], 0, PAGE_SIZE);
page_directory[pd_index] = ((uint32_t)pt_phys) | 0x3; /* Present, R/W */
page_table = (uint32_t*) pmm_alloc_page();
MEMSET(page_table, 0, PAGE_SIZE);
page_directory[pd_idx] = ((uint32_t)page_table) | PAGE_PRESENT | PAGE_WRITE;
}
else
{
page_table = (uint32_t*)(page_directory[pd_idx] & ~0xFFF);
}
page_table_entry_t* page_table = (page_table_entry_t*)((page_directory[pd_index] & 0xFFFFF000) + 0xC0000000);
page_table[pt_index] = ((uint32_t)phys_addr & 0xFFFFF000) | 0x3; /* Present, R/W */
asm volatile ("invlpg (%0)" :: "r" (virt_addr) : "memory");
page_table[pt_idx] = ((uint32_t)phys_addr) | PAGE_PRESENT | PAGE_WRITE;
}
void paging_init(void)
{
#ifdef _DEBUG
printf("[ PAGING ] Initializing paging...\n");
#endif
page_directory = (uint32_t*)pmm_alloc_page();
MEMSET(page_directory, 0, PAGE_SIZE);
for (uint32_t addr = 0; addr < 0x800000; addr += PAGE_SIZE)
{
map_page((void*) addr, (void*) addr); /* identity map first 8MB */
}
asm volatile("mov %0, %%cr3" :: "r"(page_directory));
uint32_t cr0;
asm volatile("mov %%cr0, %0" : "=r"(cr0));
cr0 |= 0x80000000;
asm volatile("mov %0, %%cr0" :: "r"(cr0));
#ifdef _DEBUG
printf("[ PAGING ] Paging initialized\n");
#endif
}

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@ -1,80 +1,76 @@
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <mm/pmm.h>
#define PAGE_SIZE 4096
#define BITMAP_SIZE (1024 * 1024) /* Supports up to 4GB RAM (1 bit per page) */
static uint8_t bitmap[BITMAP_SIZE / 8];
static uint32_t total_pages;
static uint32_t used_pages = 0;
#define MAX_PAGES (1024 * 1024) /* 4GB / 4KB */
static uint8_t bitmap[MAX_PAGES / 8] __attribute__((section(".pmm_bitmap")));
static size_t total_pages;
static inline void set_bit(uint32_t idx)
#define BITMAP_SET(i) (bitmap[(i) / 8] |= (1 << ((i) % 8)))
#define BITMAP_CLEAR(i) (bitmap[(i) / 8] &= ~(1 << ((i) % 8)))
#define BITMAP_TEST(i) (bitmap[(i) / 8] & (1 << ((i) % 8)))
void pmm_init(multiboot_info_t* mb)
{
bitmap[idx / 8] |= (1 << (idx % 8));
}
#ifdef _DEBUG
printf("[ PMM ] Initializing physical memory manager...\n");
#endif
static inline void clear_bit(uint32_t idx)
{
bitmap[idx / 8] &= ~(1 << (idx % 8));
}
static inline int test_bit(uint32_t idx)
{
return (bitmap[idx / 8] >> (idx % 8)) & 1;
}
void pmm_init(multiboot_info_t* mb_info)
{
total_pages = 0x100000; /* 4GB / 4KB = 1M pages */
for (uint32_t i = 0; i < total_pages / 8; i++)
total_pages = MAX_PAGES;
for (uint32_t i = 0; i < (total_pages / 8); i++)
{
bitmap[i] = 0xFF; /* Mark all as used */
bitmap[i] = 0xFF;
}
multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mb_info->mmap_addr;
while ((uint32_t)mmap < mb_info->mmap_addr + mb_info->mmap_length)
multiboot_memory_map_t* mmap = (void*)(uintptr_t)mb->mmap_addr;
size_t entries = mb->mmap_length / sizeof(multiboot_memory_map_t);
for (size_t i = 0; i < entries; i++)
{
if (mmap->type == 1) /* Usable */
if (mmap[i].type == 1) /* usable */
{
uint64_t base = mmap->addr;
uint64_t len = mmap->len;
for (uint64_t addr = base; addr < base + len; addr += PAGE_SIZE)
uint64_t start = mmap[i].addr;
uint64_t end = start + mmap[i].len;
for (uint64_t addr = start; addr < end; addr += 0x1000)
{
if (addr >= 0x210000) /* Skip first 2.1MB, or ≈ 2.06MiB */
if (addr >= 0x100000) /* skip below 1MB */
{
uint32_t idx = addr / PAGE_SIZE;
if (idx >= total_pages)
{
continue; /* skip entries above 4GB */
}
clear_bit(idx);
used_pages--;
size_t idx = addr / 0x1000;
BITMAP_CLEAR(idx);
}
}
}
mmap = (multiboot_memory_map_t*)((uint32_t)mmap + mmap->size + sizeof(mmap->size));
}
total_pages = MAX_PAGES;
#ifdef _DEBUG
printf("[ PMM ] Physical memory manager initialized\n");
#endif
}
void* alloc_page(void) {
for (uint32_t i = 0; i < total_pages; i++)
void* pmm_alloc_page(void)
{
for (uint32_t i = 0; i < total_pages; ++i)
{
if (!test_bit(i))
if (!BITMAP_TEST(i))
{
set_bit(i);
used_pages++;
return (void*)(i * PAGE_SIZE);
BITMAP_SET(i);
return (void*)(i * 4096);
}
}
return NULL; /* Out of memory */
printf("pmm_alloc_page(): No free page found!\n");
return NULL;
}
void free_page(void* ptr)
void pmm_free_page(void* addr)
{
uint32_t idx = (uint32_t)ptr / PAGE_SIZE;
clear_bit(idx);
size_t idx = (uintptr_t)addr / 0x1000;
BITMAP_CLEAR(idx);
}