Fixing bugs...

kernel/mem/kheap.c

@@ -0,0 +1,197 @@
+#include "kheap.h"
+#include "paging.h"
+
+// TODO: add assert
+
+extern uint32_t end;
+uint32_t placement_addr = (uint32_t)&end;
+extern page_directory_t *kernel_directory;
+heap_t *kheap = 0;
+
+uint32_t kmalloc_int(uint32_t sz, int32_t align, uint32_t *phys) {
+    if(kheap != 0) {
+        void *addr = alloc(sz, (uint8_t)align, kheap);
+        if(phys != 0) {
+            page_t *page = get_page((uint32_t)addr, 0, kernel_directory);
+            *phys = page->fr*0x1000 + ((uint32_t)addr&0xFFF);
+        }
+        return (uint32_t)addr;
+    } else {
+        if(align == 1 && (placement_addr & 0xFFFFF000)) {
+            placement_addr &= 0xFFFFF000;
+            placement_addr += 0x1000;
+        }
+        if(phys)
+            *phys = placement_addr;
+        uint32_t tmp = placement_addr;
+        placement_addr += sz;
+        return tmp;
+    }
+}
+
+void kfree(void *p) {
+    free(p, kheap);
+}
+
+uint32_t kmalloc_a(uint32_t sz) {
+    return kmalloc_int(sz, 1, 0);
+}
+
+uint32_t kmalloc_p(uint32_t sz, uint32_t *phys) {
+    return kmalloc_int(sz, 0, phys);
+}
+
+uint32_t kmalloc_ap(uint32_t sz, uint32_t *phys) {
+    return kmalloc_int(sz, 1, phys);
+}
+
+uint32_t kmalloc(uint32_t sz) {
+    return kmalloc_int(sz, 0, 0);
+}
+
+static void expand(uint32_t new_size, heap_t *heap) {
+    // Get nearest page boundary
+    if((new_size&0xFFFFF000) != 0) {
+        new_size &= 0xFFFFF000;
+        new_size += 0x1000;
+    }
+
+    uint32_t old_size = heap->end_adddress - heap->start_address;
+
+    uint32_t it = old_size;
+    while(it < new_size) {
+        alloc_frame(get_page(heap->start_address+it, 1, kernel_directory),
+        (heap->supervisor) ? 1 : 0, (heap->readonly) ? 0 : 1);
+        it += 0x1000; // Page size
+    }
+    heap->end_adddress = heap->start_address+new_size;
+}
+
+static uint32_t contract(uint32_t new_size, heap_t *heap) {
+    if(new_size&0x1000) {
+        new_size &= 0x1000;
+        new_size += 0x1000;
+    }
+
+    if(new_size < HEAP_MIN_SIZE)
+        new_size = HEAP_MIN_SIZE;
+    
+    uint32_t old_size = heap->end_adddress - heap->start_address;
+    uint32_t it = old_size - 0x1000;
+    while(new_size < it) {
+        free_frame(get_page(heap->start_address+it,0, kernel_directory));
+        it -= 0x1000;
+    }
+
+    heap->end_adddress = heap->start_address + new_size;
+    return new_size;
+}
+
+static uint32_t find_smallest_hole(uint32_t size, uint8_t page_align, heap_t *heap) {
+    uint32_t it = 0;
+
+    // Find smallest hole that fit our request
+    while(it < heap->index.size) {
+        header_t *head = (header_t*)lookup_ordered_array(it, &heap->index);
+        if(page_align > 0) {
+            // IF page must be aligned
+            uint32_t location = (uint32_t)head;
+            uint32_t offset = 0;
+            if((((location+sizeof(header_t)) & 0xFFFFF000) != 0))
+                offset = 0x1000 - (location+sizeof(header_t))%0x1000;
+            uint32_t hole_size = (uint32_t)head->size - offset;
+            // Check if we can fit this page in that hole
+            if(hole_size >= (uint32_t)size)
+                break;
+        } else if(head->size >= size)
+            break;
+        it++;
+    }
+
+    // If we didn't find anything
+    if(it == heap->index.size)
+        return -1;
+    else
+        return it;
+}
+
+static uint8_t header_t_less_than(void *a, void *b) {
+    return (((header_t*)a)->size < ((header_t*)b)->size)?1:0;
+}
+
+heap_t *create_heap(uint32_t start, uint32_t end_addr, uint32_t max, uint8_t supervisor, uint8_t readonly) {
+    heap_t *heap = (heap_t*)kmalloc(sizeof(heap_t));
+
+    // Initialize the index
+    heap->index = place_ordered_array((void*)start, HEAP_MIN_SIZE, &header_t_less_than);
+    // Shift start address to the right
+    start += sizeof(type_t) * HEAP_INDEX_SIZE;
+
+    // Check if start address is page-aligned
+    if ((start & 0xFFFFF000) != 0) {
+        start &= 0xFFFFF000;
+        start += 0x1000;
+    }
+    // Store vars into heap
+    heap->start_address = start;
+    heap->end_adddress = end_addr;
+    heap->max_address = max;
+    heap->supervisor = supervisor;
+    heap->readonly = readonly;
+
+    header_t *hole = (header_t*)start;
+    hole->size = end - start;
+    hole->magic = HEAP_MAGIC;
+    hole->is_hole = 1;
+    insert_ordered_array((void*)hole, &heap->index);
+
+    return heap;
+}
+
+void *alloc(uint32_t size, uint8_t page_align, heap_t *heap) {
+    uint32_t new_size = size + sizeof(header_t) + sizeof(footer_t);
+    // Find smallest hole suitable
+    uint32_t it = find_smallest_hole(new_size, page_align, heap);
+
+    if((int32_t)it == -1) {
+        uint32_t old_len = heap->end_adddress - heap->start_address;
+        uint32_t old_end_addr = heap->end_adddress;
+
+        // Allocate more space
+        expand(old_len+new_size, heap);
+        uint32_t new_len = heap->end_adddress - heap->start_address;
+
+        it = 0;
+        uint32_t idx = -1; uint32_t value = 0x0;
+        while(it < heap->index.size) {
+            uint32_t tmp = (uint32_t)lookup_ordered_array(it, &heap->index);
+            if(tmp > value) {
+                value = tmp;
+                idx = it;
+            }
+            it++;
+        }
+
+        // If no headers has been found, add a new one
+        if((int32_t)idx == -1) {
+            header_t *head = (header_t*)old_end_addr;
+            head->magic = HEAP_MAGIC;
+            head->size = new_len - old_len;
+            head->is_hole = 1;
+    
+            footer_t *foot = (footer_t*)(old_end_addr + head->size - sizeof(footer_t));
+            foot->magic = HEAP_MAGIC;
+            foot->header = head;
+            insert_ordered_array((void*)head, &heap->index);
+        } else {
+            header_t *head = lookup_ordered_array(idx, &heap->index);
+            head->size += new_len - old_len;
+            // Update the footer
+            footer_t *foot = (footer_t*)((uint32_t)head + head->size - sizeof(footer_t));
+            foot->header = head;
+            foot->magic = HEAP_MAGIC;
+        }        
+        // Now we have enough space, so recall this function again
+        return alloc(size, page_align, heap);
+    }
+}

kernel/mem/kheap.h

@@ -61,13 +61,11 @@ heap_t *create_heap(uint32_t start, uint32_t end, uint32_t max, uint8_t supervis
 void *alloc(uint32_t size, uint8_t page_align, heap_t *heap);
 // Free a block allocated with alloc
 void free(void *p, heap_t *heap);
-uint32_t kmalloc_int(uint32_t sz, int align, uint32_t *phys);
+uint32_t kmalloc_int(uint32_t sz, int32_t align, uint32_t *phys);
 uint32_t kmalloc_a(uint32_t sz);
 uint32_t kmalloc_p(uint32_t sz, uint32_t *phys);
 uint32_t kmalloc_ap(uint32_t sz, uint32_t *phys);
 uint32_t kmalloc(uint32_t sz);
 void kfree(void *p);
 
-
-
 #endif

kernel/mem/paging.c

@@ -2,17 +2,11 @@
 #include "../libc/string.h"
 #include "../libc/assert.h"
 #include "../drivers/tty.h"
-// #include "kheap.h" FIXME:
 
 // External definitions from kheap.c
 extern uint32_t placement_addr;
 extern heap_t *kheap;
 
-void map_heap_pages();
-void setup_frame_allocations();
-void setup_page_directory();
-void alloc_heap_pages();
-
 // Bitset of frames, used or free
 uint32_t *frame_allocations;
 uint32_t nframes; // Number of physical frames
@@ -55,7 +49,7 @@ void alloc_frame(page_t *page, int32_t is_super, int32_t is_write) {
             page->pr = PAGE_PRESENT;
             page->rw = (is_write) ? PAGE_READ_WRITE : PAGE_READ_ONLY;
             page->us = (is_super) ? PAGE_SUPERVISOR : PAGE_USER;
-            page->fr = free_frame;
+            page->fr = fframe;
             // Set new frames as used
             uint32_t physical_addr = fframe * FRAME_SIZE;
             set_frame(physical_addr);
@@ -74,11 +68,22 @@ void free_frame(page_t *page) {
 }
 
 void init_paging() {
-    setup_frame_allocations();
+    kernel_directory = (page_directory_t*)kmalloc_a(sizeof(page_directory_t));
-    setup_page_directory();
+    memset(kernel_directory, 0, sizeof(page_directory_t));
-    map_heap_pages();
+    current_directory = kernel_directory;
-    identity_map();
+
-    alloc_heap_pages();
+    kernel_directory = (page_directory_t*)kmalloc_a(sizeof(page_directory_t));
+    memset(kernel_directory, 0, sizeof(page_directory_t));
+    current_directory = kernel_directory;
+
+    for(uint32_t i = KHEAP_START; i < KHEAP_START + KHEAP_INITIAL_SIZE; i += FRAME_SIZE)
+        get_page(i, 1, kernel_directory);
+
+    for(uint32_t i  = 0; i < placement_addr + FRAME_SIZE; i += FRAME_SIZE)
+        alloc_frame(get_page(i, 1, kernel_directory), 0, 0);
+    
+    for(uint32_t i = KHEAP_START; i < KHEAP_START+KHEAP_INITIAL_SIZE; i += FRAME_SIZE)
+        alloc_frame(get_page(i, 1, kernel_directory), 0, 0);
 
     // Register a new ISR to listen to IRQ 14
     register_interrupt_handler(14, page_fault);
@@ -86,38 +91,11 @@ void init_paging() {
     kheap = create_heap(KHEAP_START, KHEAP_START+KHEAP_INITIAL_SIZE, 0xCFFFF000, 0, 0);
 }
 
-void map_heap_pages() {
-    for(uint32_t i = KHEAP_START; i < KHEAP_START + KHEAP_INITIAL_SIZE; i != FRAME_SIZE)
-        get_page(i, 1, kernel_directory);
-}
-
-void setup_frame_allocations() {
-    nframes = PHYSICAL_MEM_SIZE / FRAME_SIZE;
-    frame_allocations = (uint32_t*)kmalloc(nframes / FRAME_ALLOCATIONS_SECTION_SIZE);
-    memset(frame_allocations, 0, nframes/FRAME_ALLOCATIONS_SECTION_SIZE);
-}
-
-void setup_page_directory() {
-    kernel_directory = (page_directory_t*)kmalloc_a(sizeof(page_directory_t));
-    memset(kernel_directory, 0, sizeof(page_directory_t));
-    current_directory = kernel_directory;
-}
-
-void alloc_heap_pages() {
-    for(uint32_t i = KHEAP_START; i < KHEAP_START+KHEAP_INITIAL_SIZE; i += FRAME_SIZE)
-        alloca_frame(get_page(i, 1, kernel_directory), 0, 0);
-}
-
-void identity_map() {
-    for(uint32_t i  = 0; i < placement_addr + FRAME_SIZE; i += FRAME_SIZE)
-        alloc_frame(get_page(i, 1, kernel_directory), 0, 0);
-}
-
 void enable_paging(page_directory_t *dir) {
     current_directory = dir;
     asm volatile("mov %0, %%cr3" :: "r"(&dir->page_tables_physical));
     uint32_t cr0;
-    asm volatile("mov %%cr0, %d" : "=r"(cr0));
+    asm volatile("mov %%cr0, %0" : "=r"(cr0));
     cr0 |= 0x80000000; // Correct code to enable paging
     asm volatile("mov %0, %%cr0" :: "r"(cr0));
 }
@@ -129,7 +107,7 @@ page_t *get_page(uint32_t address, int32_t make, page_directory_t *dir) {
         return &dir->page_tables_virtual[table_idx]->pages[address%1024];
     else if(make) {
         uint32_t tmp;
-        dir->page_tables_virtual[table_idx] = (page_table_t*)kmalloc_sp(sizeof(page_table_t), &tmp);
+        dir->page_tables_virtual[table_idx] = (page_table_t*)kmalloc_ap(sizeof(page_table_t), &tmp);
         memset(dir->page_tables_virtual[table_idx], 0, 0x1000);
         dir->page_tables_physical[table_idx] = tmp | 0x7;
         return &dir->page_tables_virtual[table_idx]->pages[address%1024];

kernel/mem/paging.h

@@ -10,6 +10,7 @@
 
 #include <stdint.h>
 #include "../drivers/isr.h"
+#include "kheap.h"
 
 #define FRAME_SIZE 4096
 #define PAGE_TABLE_SIZE 1024