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#include "init.h"
#include "bootargs.h"
#include "device/initrd.h"
#include "arch/x86_64/page.h"
#include "arch/x86_64/processor.h"
#include "device/processor.h"
#include "print.h"
#include "elf.h"
#include "string.h"
uintptr_t
init_alloc_pageframe()
{
objdir_entry_t *untyped_dir_entry = &_initDirectory.entries[INIT_OBJECT_UNTYPED_DIR];
objdir_t *untyped_dir = ko_entry_data(untyped_dir_entry);
/*Seek to the last member of untyped directory.*/
uint8_t lastmembi = 1;
for(; untyped_dir->entries[lastmembi].type == KO_MEMORY_UNTYPED; lastmembi++);
objdir_entry_t *lastmemb = &untyped_dir->entries[lastmembi-1];
objdir_entry_t pageframe;
ko_untyped_split(lastmemb, &pageframe, 0x1000);
return pageframe.data;
}
void
init_map_pageframe(uintptr_t pptr, uintptr_t vptr, uint64_t pflags)
{
uint64_t pathval;
uint16_t *path = (uint16_t*)&pathval;
pml4_get_path(vptr, 4, path);
processor_t *proc = processor_current();
pmle_t *pml4 = pptr_tovirt_ident(proc->pdir);
pmle_t *pmld = pml4;
for(uint8_t d = 0; d < 3; d++) {
uint16_t pmli = path[d];
pmle_t *pmle = &pmld[pmli];
if(!pmle->p) {
pmle->value = init_alloc_pageframe() | PAGE_PRESENT | PAGE_RW | PAGE_US;
}
pmld = pptr_tovirt_ident(pmle->paddr << 12);
}
pmld[path[3]].value = pptr | pflags;
__asm__ volatile("invlpg (%0)":: "r"(vptr): "memory");
}
void
init_ensure_page(uintptr_t vptr, uint8_t pflags)
{
uint64_t pathval;
uint16_t *path = (uint16_t*)&pathval;
pml4_get_path(vptr, 4, path);
processor_t *proc = processor_current();
pmle_t *pml4 = pptr_tovirt_ident(proc->pdir);
pmle_t *pmld = pml4, *pmle = NULL;
for(uint8_t d = 0; d < 4; d++) {
uint16_t pmli = path[d];
pmle = &pmld[pmli];
if(!pmle->p) {
physptr_t frame = init_alloc_pageframe();
pmle->value = frame | (d == 3 ? pflags : (PAGE_PRESENT | PAGE_RW | PAGE_US));
if(d != 3) memset(pptr_tovirt_ident(frame), 0, 0x1000);
pmle->p = 1;
}
pmld = pptr_tovirt_ident(pmle->paddr << 12);
}
__asm__ volatile("invlpg (%0)":: "r"(vptr): "memory");
}
void
init_reperm_page(uintptr_t vptr, uint64_t pflags)
{
uint64_t pathval;
uint16_t *path = (uint16_t*)&pathval;
pml4_get_path(vptr, 4, path);
processor_t *proc = processor_current();
pmle_t *pml4 = pptr_tovirt_ident(proc->pdir);
pmle_t *pmld = pml4, *pmle = NULL;
for(uint8_t d = 0; d < 4; d++) {
uint16_t pmli = path[d];
pmle = &pmld[pmli];
if(!pmle->p) {
return;
}
pmld = pptr_tovirt_ident(pmle->paddr << 12);
}
pmle->rw = pflags & PAGE_RW ? 1 : 0;
pmle->xd = pflags & PAGE_XD ? 1 : 0;
__asm__ volatile("invlpg (%0)":: "r"(vptr): "memory");
}
void
init_ensure_range(uintptr_t base, size_t width, uint64_t pflags)
{
if(width & 0xFFF) width = (width | 0xFFF) + 1;
width >>= 12;
for(size_t i = 0; i < width; i++) {
init_ensure_page(base + (i << 12), pflags);
}
}
void
init_reperm_range(uintptr_t base, size_t width, uint64_t pflags)
{
if(width & 0xFFF) width = (width | 0xFFF) + 1;
width >>= 12;
for(size_t i = 0; i < width; i++) {
init_reperm_page(base + (i << 12), pflags);
}
}
void
init_load(void)
{
char *init_arg = bootargs_getarg("init");
if(init_arg == NULL) {
klogf("init not specified in bootargs!\n");
return;
}
tar_header_t *init_file = initrd_find_file(init_arg);
if(init_file == NULL) {
klogf("init not found in initrd! (filename %s)\n", init_arg);
return;
}
uint8_t *init_data = (uint8_t*)&((tar_block_t*)init_file)[1];
Elf64_Ehdr *init_ehdr = (Elf64_Ehdr*)init_data;
if(!elf64_ehdr_valid(init_ehdr)) {
klogf("init is not a proper ELF executable!\n");
return;
}
uintptr_t program_end = 0;
for(size_t phdri = 0; phdri < init_ehdr->e_phnum; phdri++) {
Elf64_Phdr *phdr = &((Elf64_Phdr*)(init_data + init_ehdr->e_phoff))[phdri];
if(phdr->p_type == PT_LOAD) {
uintptr_t section_base = phdr->p_vaddr;
size_t section_size = phdr->p_memsz;
size_t section_cpysize = phdr->p_filesz;
if(section_base + section_size > program_end) {
program_end = section_base + section_size;
if(program_end & 0xFFF) program_end = ((program_end >> 12) + 1) << 12;
}
klogf("ELF LOAD %p %p %p %x\n", section_base, section_size, section_cpysize, phdr->p_flags);
init_ensure_range(section_base, section_size, PAGE_PRESENT | PAGE_US | PAGE_RW);
memcpy((void*)section_base, init_data + phdr->p_offset, section_cpysize);
memset((void*)(section_base + section_cpysize), 0, (section_size - section_cpysize));
init_reperm_range(section_base, section_size, (phdr->p_flags & PF_W ? PAGE_RW : 0) |
(!(phdr->p_flags & PF_X) ? PAGE_XD : 0));
}
}
//Allocate usermode stack.
uintptr_t usermode_stack_base = 0x00007FFFFFFFE000;
init_ensure_range(usermode_stack_base, 0x2000, PAGE_PRESENT | PAGE_RW | PAGE_US | PAGE_XD);
uintptr_t *usermode_sp = (uintptr_t*)(usermode_stack_base + 0x1FF8);
//Allocate syscall message.
uintptr_t message_frame = init_alloc_pageframe();
init_map_pageframe(message_frame, program_end, PAGE_PRESENT | PAGE_RW | PAGE_US | PAGE_XD);
_initDirectory.entries[INIT_OBJECT_MESSAGE] = (objdir_entry_t) {
.type = KO_MESSAGE,
.extra = KODE_EX_MESSAGE_MAPPED,
.data = program_end
};
*(--usermode_sp) = program_end;
extern tcb_t *_init_tcb;
_init_tcb->sp = (uintptr_t)usermode_sp;
usermode((void*)init_ehdr->e_entry, usermode_sp);
}
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