did some restructuring, got multitasking almost working

kernel/kmain.c

@@ -1,150 +1,62 @@
 #include "multiboot.h"
-#include "idt.h"
+#include "interrupts.h"
 #include "elf.h"
+#include "gdt.h"
+#include "scheduler.h"
 
 #include <lib/print.h>
 #include <lib/stream.h>
 #include <lib/memory.h>
 
-#include "memory/mm.h"
+#include <memory/mm.h>
 
-#include "drivers/iso/iso.h"
-#include "drivers/ide/ide.h"
+#include <drivers/iso/iso.h>
+#include <drivers/ide/ide.h>
+#include <drivers/pic/pic.h>
+#include <drivers/ps2/ps2.h>
+#include <drivers/pit/pit.h>
+#include <drivers/vga/vga.h>
 
 #include <stddef.h>
 #include <stdint.h>
 
-extern void init_idt();
-extern void init_gdt();
-extern void init_pic();
-extern void init_pit();
-extern int init_ps2();
 extern void enable_interrupts();
-
-void* page = NULL;
+extern void disable_interrupts();
+extern uint32_t fetch_cr3();
 
 extern char __kernel_start;
 extern char __kernel_end;
 
-void* user_page_directories[10];
-
-void load_origin_program(multiboot_info* mbi) {
-  user_page_directories[0] = create_user_pd();
-  kprintf("Created origin process page directory @ [phys] 0x%x\n", user_page_directories[0]);
-  extern void load_pd(void* pd);
-  extern void flush_tlb();
-  load_pd(user_page_directories[0]);
-  flush_tlb();
-  kprintf("switched to user address space\n");
-
-  uint32_t mods_virtual_addr = mbi->mods_addr + 0xC0000000;
-  kprintf("parsing mutliboot modules @ 0x%x\n", mods_virtual_addr);
-
-  if (mbi->mods_count == 0) {
-    return;
+void kernel_test_task() {
+  while (1) {
+    kprintf("task sleeping...\n");
+    sleep(10000000);
   }
-
-  multiboot_module_entry* modules = (multiboot_module_entry*)mods_virtual_addr;
-
-  uint32_t elf_vbase = 0xE0000000;
-  uint32_t elf_pbase = modules[0].mod_start;
-  uint32_t elf_limit = modules[0].mod_end - modules[0].mod_start;
-  uint32_t elf_pages_needed = (elf_limit / 4096) + 1;
-
-  for (uint32_t i = 0; i < elf_pages_needed; i++) {
-    const uint32_t vaddr = elf_vbase + (i * 4096);
-    const uint32_t paddr = elf_pbase + (i * 4096);
-    map_page(vaddr, paddr, PAGE_PRESENT | PAGE_WRITABLE);
-  }
-
-  elf_header_t* elf = (elf_header_t*)elf_vbase;
-  elf_program_header_t* ph = (elf_program_header_t*)(elf_vbase + elf->e_phoff);
-
-  kprintf("elf header @ 0x%x\n", elf);
-  kprintf("program headers @ 0x%x\n", ph);
-
-  // load program sections into physical memory and map the pages
-  for (int i = 0; i < elf->e_phnum; i++) {
-    if (ph[i].p_type == PT_LOAD) {
-      uint32_t v_start = ph[i].p_vaddr & 0xFFFFF000;
-      uint32_t v_end = (ph[i].p_vaddr + ph[i].p_memsz + 4095) & 0xFFFFF000;
-
-      for (uint32_t page = v_start; page < v_end; page += 4096) {
-        uint32_t frame_paddr = (uint32_t)p_alloc_frame();
-        map_page(page, frame_paddr, PAGE_PRESENT | PAGE_WRITABLE | PAGE_USER);
-      }
-
-      for (uint32_t j = 0; j < ph[i].p_memsz; j++) {
-        ((char*)ph[i].p_vaddr)[j] = 0;
-      }
-
-      for (uint32_t j = 0; j < ph[i].p_filesz; j++) {
-        ((char*)ph[i].p_vaddr)[j] = ((char*)(elf_vbase + ph[i].p_offset))[j];
-      }
-    }
-  }
-
-  // allocate the user stack
-  uint32_t stack_paddr = (uint32_t)p_alloc_frame();
-  map_page(0xBFFFF000, stack_paddr, PAGE_PRESENT | PAGE_WRITABLE | PAGE_USER);
-
-  kprintf("program loaded into memory @ [virt] 0x%x\n", elf->e_entry);
-
-  extern void liftoff(uint32_t entry, uint32_t stack_top);
-  kprintf("launching origin process\n");
-  uint32_t stack_top =  0xBFFFF000 + 4095;
-  liftoff(elf->e_entry, stack_top);
 }
 
 void kmain(uint32_t magic, multiboot_info* mbi)  {
-  extern print_stream_t vga_print_stream;
-  extern print_stream_t* kout;
-  kout = &vga_print_stream;
-  kout->trunc();
-
-  kprintf("kernel start: 0x%x\n", &__kernel_start);
-  kprintf("kernel end: 0x%x\n", &__kernel_end);
-  uint32_t size = (&__kernel_end - &__kernel_start) / 1024;
-  kprintf("kernel size: %dKB\n", size);
-
   if (!(mbi->flags & (1 << 6))) {
     return;
   } 
 
-  kprintf("multiboot virtual address: 0x%x\n", mbi);
+  vga_init();
 
-  kprintf("parsing multiboot memory map\n");
   uint32_t mmap_virtual_addr = mbi->mmap_addr + 0xC0000000;
-  kprintf("mmap virtual address: 0x%x\n", mmap_virtual_addr);
   init_pmm((void*)mmap_virtual_addr, mbi->mmap_length);
+  kprintf("memory detection complete. total free memory: %dMB\n", total_free_memory() / 1024 / 1024);
 
-  kprintf("RockOS booting...\n");
   init_gdt();
-  extern uint64_t gdt[5];
-  kprintf("GDT set @ 0x%x\n", &gdt);
- 
   init_idt();
-  extern idt_entry idt[256];
-  kprintf("IDT set @ 0x%x\n", &idt);
-
   init_pic();
-  kprintf("PIC initialized\n");
-
   init_pit();
-  kprintf("PIT initialized\n"); 
-
+  
   init_page_tables();
-  kprintf("Page tables initialized\n");
 
-  kgrow(1);
-  kprintf("Allocated 4kb for kernel heap\n");
+  kprintf("basic initializations complete\n");
 
-  kprintf("scanning for drives\n");
-  extern void scan_drives();
-  scan_drives();
+  disable_interrupts();
+  init_scheduler();
+  enable_interrupts();
 
-  ide_device_t* boot_cd_rom = get_ide_device(0);
-  read_iso(boot_cd_rom);
-
-  while(1);
+  while(1) yield();
 }