saper!!!1111!1!!!11

io.h

@@ -0,0 +1,17 @@
+static inline void outb(uint16_t port, uint8_t val) {
+	__asm__ volatile(
+		"outb %0, %1\n"
+		:
+		: "a"(val), "d"(port)
+	);
+}
+
+static inline uint8_t inb(uint16_t port) {
+	uint8_t res;
+	__asm__ volatile(
+		"inb %1, %0\n"
+		: "=a"(res)
+		: "d"(port)
+	);
+	return res;
+}

main.c

@@ -1,29 +1,224 @@
 #include <stdint.h>
+#include <stddef.h>
+#include <elf.h>
 #include "gdt.h"
+#include "msr.h"
 #include "page.h"
+#include "io.h"
 char hello[] = "Hello, C world!";
 
+void *memset(void *s, int c, size_t n) {
+	unsigned char *p = s;
+	while (n--)
+		*p++ = c;
+	return s;
+}
+
+void *memcpy(void *s, void *ss, size_t n) {
+	unsigned char *p = s;
+	unsigned char *pp = ss;
+	while (n--)
+		*p++ = *pp++;
+	return s;
+}
+
 __asm__(
 	".text\n"
 	"go_user:\n"
 	"pushq $0x1b\n"
-	"pushq $0\n"
+	"pushq %rsi\n"
 	"pushq $0x2\n"
 	"pushq $0x23\n"
 	"pushq %rdi\n"
 	"iretq\n"
 );
 
-_Noreturn void go_user(void *);
+__asm__(
+	"lstar:\n"
+	"pushq %rcx\n"
+	"pushq %r8\n"
+	"pushq %r9\n"
+	"pushq %r11\n"
+	"pushq %r10\n"
+	"pushq %rdx\n"
+	"pushq %rsi\n"
+	"pushq %rdi\n"
+	"movq %rax, %rdi\n"
+	"movq %rsp, %rsi\n"
+	"call csyscall\n"
+	"popq %rdi\n"
+	"popq %rsi\n"
+	"popq %rdx\n"
+	"popq %r10\n"
+	"popq %r11\n"
+	"popq %r9\n"
+	"popq %r8\n"
+	"popq %rcx\n"
+	"sysretq\n"
+);
+
+__asm__(
+	"cstar:\n"
+	"cli\n"
+	"hlt\n"
+);
+
+extern void lstar;
+extern void cstar;
+
+_Noreturn void go_user(void *, uint64_t);
+
+void sys_print(unsigned x, unsigned y, uint16_t *chars, unsigned n) {
+	unsigned i;
+	for (i = 0; i < n; i++) {
+		int c = chars[i];
+		if (x < 80 && y < 25) {
+			volatile uint16_t *screen = (void *)0xffff8000000b8000ull;
+			screen[y * 80 + x] = c;
+		}
+		x++;
+	}
+}
+
+void sys_setcursor(unsigned x, unsigned y) {
+	if (x >= 80)
+		return;
+	if (y >= 25)
+		return;
+	unsigned addr = x + y * 80;
+	outb(0x3d4, 0xe);
+	outb(0x3d5, addr >> 8);
+	outb(0x3d4, 0xf);
+	outb(0x3d5, addr);
+}
+
+int kbd_getbyte(void) {
+	while (!(inb(0x64) & 1));
+	return inb(0x60);
+}
+
+int kbd_getcode(void) {
+	int k = kbd_getbyte();
+	if (k != 0xe0)
+		return k;
+	return kbd_getbyte() | 0x100;
+}
+
+__asm__(
+	".text\n"
+	"sys_getrand:\n"
+	"rdrand %eax\n"
+	"jnc sys_getrand\n"
+	"retq\n"
+);
+int sys_getrand(void);
+
+int sys_getkey(void) {
+	int k;
+	while (1) {
+		k = kbd_getcode();
+		switch (k) {
+			case 0x1c:
+				return '\n';
+			case 0x1f:
+				return 's';
+			case 0x39:
+				return ' ';
+			case 0x14b:
+				return 0x81;
+			case 0x14d:
+				return 0x83;
+			case 0x148:
+				return 0x80;
+			case 0x150:
+				return 0x82;
+		}
+	}
+}
+
+uint64_t csyscall(uint64_t func, uint64_t *regs) {
+	switch (func) {
+		case 0:
+			outb(0x64, 0xfe);
+			while (1);
+			return 0;
+		case 1:
+			return sys_getrand();
+		case 2:
+			return sys_getkey();
+		case 3:
+			sys_print(regs[0], regs[1], (void *)regs[2], regs[3]);
+			return 0;
+		case 4:
+			sys_setcursor(regs[0], regs[1]);
+			return 0;
+		default:
+			return -1;
+	}
+}
+
+__asm__(
+	".section .rodata\n"
+	"user_prog:\n"
+	".incbin \"prog\"\n"
+	".text\n"
+);
+
+extern void user_prog;
 
 void main() {
 	init_gdt();
 	init_pg();
-	map_page(0x31337000, phys_alloc(), 7);
+	// ELF loader start
+	Elf64_Ehdr *ehdr = &user_prog;
+	int i;
+	for (i = 0; i < ehdr->e_phnum; i++) {
+		Elf64_Phdr *phdr = &user_prog + ehdr->e_phoff + ehdr->e_phentsize * i;
+		if (phdr->p_type == PT_LOAD) {
+			uint64_t va = phdr->p_vaddr & ~0xfffull;
+			uint64_t end = phdr->p_vaddr + phdr->p_memsz;
+			for (uint64_t p = va; p < end; p += 0x1000) {
+				map_page(p, phys_alloc(), 7);
+			}
+			memset((void*)phdr->p_vaddr, 0, phdr->p_memsz);
+			memcpy((void*)phdr->p_vaddr, &user_prog + phdr->p_offset, phdr->p_filesz);
+		}
+	}
+	for (i = 0; i < ehdr->e_phnum; i++) {
+		Elf64_Phdr *phdr = &user_prog + ehdr->e_phoff + ehdr->e_phentsize * i;
+		if (phdr->p_type == 0x60031337) {
+			*(uint32_t *)phdr->p_vaddr = 200;
+		}
+	}
+#if 0
 	uint8_t *upage = (void *)0x31337000ull;
 	upage[0] = 0xeb;
 	upage[1] = 0xfe;
-	go_user(upage);
+#endif
+	wrmsr(0xC0000081, 0x0013000800000000ull);
+	wrmsr(0xC0000082, (uint64_t)&lstar);
+	wrmsr(0xC0000083, (uint64_t)&cstar);
+	wrmsr(0xC0000084, 0xffffffff);
+
+#if 0
+	int x = 0;
+	while (1) {
+		int k = sys_getkey();
+		k = sys_getrand();
+		uint16_t c[2] = {
+			0x0f00 | (k >> 4 & 0xf)["0123456789abcdef"],
+			0x0f00 | (k & 0xf)["0123456789abcdef"],
+		};
+		sys_print(x, 0, c, 2);
+		x += 2;
+		x %= 80;
+		sys_setcursor(x, 0);
+	}
+#endif
+	sys_getkey();
+	for (int i = 0x1000; i < 0x100000; i += 0x1000)
+		map_page(i, phys_alloc(), 7);
+	go_user((void *)ehdr->e_entry, 0x100000);
 	for (int i = 0; i < sizeof hello; i++) {
 		*(uint16_t *)(0x31337000 + i * 2) = hello[i] | 0x0f00;
 	}

msr.h

@@ -0,0 +1,9 @@
+static inline void wrmsr(uint32_t reg, uint64_t val) {
+	uint32_t lo = val;
+	uint32_t hi = val >> 32;
+	__asm__ volatile (
+		"wrmsr"
+		:
+		: "a"(lo), "d"(hi), "c"(reg)
+	);
+}

page.c

@@ -20,16 +20,28 @@ void map_page(uint64_t virt, uint64_t phys, int flags) {
 	int idx2 = virt >> 21 & 0x1ff;
 	int idx3 = virt >> 30 & 0x1ff;
 	int idx4 = virt >> 39 & 0x1ff;
-	if (!v_ptl4[idx4])
+	if (!v_ptl4[idx4]) {
 		v_ptl4[idx4] = phys_alloc() | 7;
+		uint64_t p_ptl3 = v_ptl4[idx4] & ~0xfffull;
+		uint64_t *v_ptl3 = P2V(p_ptl3);
+		memset(v_ptl3, 0, 0x1000);
+	}
 	uint64_t p_ptl3 = v_ptl4[idx4] & ~0xfffull;
 	uint64_t *v_ptl3 = P2V(p_ptl3);
-	if (!v_ptl3[idx3])
+	if (!v_ptl3[idx3]) {
 		v_ptl3[idx3] = phys_alloc() | 7;
+		uint64_t p_ptl2 = v_ptl3[idx3] & ~0xfffull;
+		uint64_t *v_ptl2 = P2V(p_ptl2);
+		memset(v_ptl2, 0, 0x1000);
+	}
 	uint64_t p_ptl2 = v_ptl3[idx3] & ~0xfffull;
 	uint64_t *v_ptl2 = P2V(p_ptl2);
-	if (!v_ptl2[idx2])
+	if (!v_ptl2[idx2]) {
 		v_ptl2[idx2] = phys_alloc() | 7;
+		uint64_t p_ptl1 = v_ptl2[idx2] & ~0xfffull;
+		uint64_t *v_ptl1 = P2V(p_ptl1);
+		memset(v_ptl1, 0, 0x1000);
+	}
 	uint64_t p_ptl1 = v_ptl2[idx2] & ~0xfffull;
 	uint64_t *v_ptl1 = P2V(p_ptl1);
 	v_ptl1[idx1] = phys | flags;

prog

@@ -0,0 +1 @@
+/home/mwk/zzad/z1/prog