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#include <multiboot.h>
#include <config.h>
#include <dbglog.h>
#include <sys.h>
#include <malloc.h>
#include <gdt.h>
#include <idt.h>
#include <frame.h>
#include <paging.h>
#include <region.h>
#include <kmalloc.h>
#include <thread.h>
#include <vfs.h>
#include <nullfs.h>
#include <process.h>
#include <elf.h>
#include <syscall.h>
#include <slab_alloc.h>
#include <string.h>
// ===== FOR TESTS =====
#define TEST_PLACEHOLDER_AFTER_IDT
#define TEST_PLACEHOLDER_AFTER_REGION
#define TEST_PLACEHOLDER_AFTER_KMALLOC
#define TEST_PLACEHOLDER_AFTER_TASKING
#define TEST_PLACEHOLDER_AFTER_DEVFS
#ifdef IS_A_TEST
#define BEGIN_TEST(n) dbg_printf("(BEGIN-TEST %s)\n", n);
#define TEST_OK { dbg_printf("(TEST-OK)\n"); asm volatile("cli; hlt"); }
#include <test.c>
#endif
// ===== / FOR TESTS ====
extern const void k_end_addr; // defined in linker script : 0xC0000000 plus kernel stuff
void breakpoint_handler(registers_t *regs) {
dbg_printf("Breakpoint! (int3)\n");
dbg_dump_registers(regs);
BOCHS_BREAKPOINT;
}
void kernel_init_stage2(void* data);
void kmain(multiboot_info_t *mbd, int32_t mb_magic) {
// used for allocation of data structures before malloc is set up
// a pointer to this pointer is passed to the functions that might have
// to allocate memory ; they just increment it of the allocated quantity
void* kernel_data_end = (void*)&k_end_addr;
dbglog_setup();
dbg_printf("Hello, kernel world!\n");
dbg_printf("This is %s, version %s.\n", OS_NAME, OS_VERSION);
ASSERT(mb_magic == MULTIBOOT_BOOTLOADER_MAGIC);
// Rewrite multiboot header so that we are in higher half
// Also check that kernel_data_end is after all modules, otherwise
// we might overwrite something.
mbd->cmdline += K_HIGHHALF_ADDR;
size_t cmdline_end = mbd->cmdline + strlen((char*)mbd->cmdline);
void* cmdline_end_pa = (void*)((cmdline_end & 0xFFFFF000) + 0x1000);
if (cmdline_end_pa > kernel_data_end) kernel_data_end = cmdline_end_pa;
mbd->mods_addr += K_HIGHHALF_ADDR;
multiboot_module_t *mods = (multiboot_module_t*)mbd->mods_addr;
for (unsigned i = 0; i < mbd->mods_count; i++) {
mods[i].mod_start += K_HIGHHALF_ADDR;
mods[i].mod_end += K_HIGHHALF_ADDR;
mods[i].string += K_HIGHHALF_ADDR;
void* mod_end_pa = (void*)((mods[i].mod_end & 0xFFFFF000) + 0x1000);
if (mod_end_pa > kernel_data_end)
kernel_data_end = mod_end_pa;
}
gdt_init(); dbg_printf("GDT set up.\n");
idt_init(); dbg_printf("IDT set up.\n");
idt_set_ex_handler(EX_BREAKPOINT, breakpoint_handler);
TEST_PLACEHOLDER_AFTER_IDT;
size_t total_ram = ((mbd->mem_upper + mbd->mem_lower) * 1024);
dbg_printf("Total ram: %d Kb\n", total_ram / 1024);
frame_init_allocator(total_ram, &kernel_data_end);
dbg_printf("kernel_data_end: 0x%p\n", kernel_data_end);
dbg_print_frame_stats();
paging_setup(kernel_data_end);
dbg_printf("Paging seems to be working!\n");
region_allocator_init(kernel_data_end);
TEST_PLACEHOLDER_AFTER_REGION;
kmalloc_setup();
TEST_PLACEHOLDER_AFTER_KMALLOC;
setup_syscalls();
// enter multi-threading mode
// interrupts are enabled at this moment, so all
// code run from now on should be preemtible (ie thread-safe)
threading_setup(kernel_init_stage2, mbd);
PANIC("Should never come here.");
}
void kernel_init_stage2(void* data) {
multiboot_info_t *mbd = (multiboot_info_t*)data;
dbg_print_region_info();
dbg_print_frame_stats();
TEST_PLACEHOLDER_AFTER_TASKING;
// Create devfs
register_nullfs_driver();
fs_t *devfs = make_fs("nullfs", 0, "cd");
ASSERT(devfs != 0);
// Add kernel command line to devfs
{
dbg_printf("Kernel command line: '%s'\n", (char*)mbd->cmdline);
size_t len = strlen((char*)mbd->cmdline);
fs_handle_t* cmdline = fs_open(devfs, "/cmdline", FM_WRITE | FM_CREATE);
ASSERT(cmdline != 0);
ASSERT(file_write(cmdline, 0, len, (char*)mbd->cmdline) == len);
unref_file(cmdline);
}
// Populate devfs with files for kernel modules
ASSERT(fs_create(devfs, "/mod", FT_DIR));
multiboot_module_t *mods = (multiboot_module_t*)mbd->mods_addr;
for (unsigned i = 0; i < mbd->mods_count; i++) {
char* modname = (char*)mods[i].string;
char* e = strchr(modname, ' ');
if (e != 0) (*e) = 0; // ignore arguments
char *b = strrchr(modname, '/');
if (b != 0) modname = b+1; // ignore path
char name[6 + strlen(b)];
strcpy(name, "/mod/");
strcpy(name+5, modname);
size_t len = mods[i].mod_end - mods[i].mod_start;
dbg_printf("Adding module to VFS: '%s' (size %d)\n", name, len);
/*
// This would be the "good" way of doing it :
fs_handle_t* mod_f = fs_open(devfs, name, FM_WRITE | FM_CREATE);
ASSERT(mod_f != 0);
ASSERT(file_write(mod_f, 0, len, (char*)mods[i].mod_start) == len);
unref_file(mod_f);
*/
// But since we have a nullfs, we can do it that way to prevent useless data copies :
ASSERT(nullfs_add_ram_file(devfs, name,
(char*)mods[i].mod_start,
len, false, FM_READ | FM_MMAP));
}
TEST_PLACEHOLDER_AFTER_DEVFS;
fs_handle_t *init_bin = fs_open(devfs, "/mod/init.bin", FM_READ | FM_MMAP);
if (init_bin == 0) PANIC("No init.bin module provided!");
if (!is_elf(init_bin)) PANIC("init.bin is not valid ELF32 binary");
process_t *init_p = new_process(0);
ASSERT(init_p != 0);
bool add_devfs_ok = proc_add_fs(init_p, devfs, "dev");
ASSERT(add_devfs_ok);
proc_entry_t *e = elf_load(init_bin, init_p);
if (e == 0) PANIC("Could not load ELF file init.bin");
unref_file(init_bin);
start_process(init_p, e);
//TODO :
// - (OK) populate devfs with information regarding kernel command line & modules
// - create user process with init module provided on command line
// - give it rights to devfs
// - launch it
// - just return, this thread is done
dbg_printf("Reached kmain end! I'll just stop here and do nothing.\n");
}
/* vim: set ts=4 sw=4 tw=0 noet :*/
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