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Well, seems to work

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This commit is contained in:
Mark
2020-01-30 13:24:00 +02:00
parent fd374087b0
commit 1e631fc03a
5 changed files with 157 additions and 6 deletions
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include/sys/amd64/cpu.h
+2 -3
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@@ -9,9 +9,8 @@ struct cpu {
// TODO: somehow export offsets to asm
struct cpu *self; // 0x00
uint64_t ticks;
amd64_tss_t *tss;
uint64_t syscall_rsp;
uint64_t ticks; // 0x08
amd64_tss_t *tss; // 0x10
uint64_t processor_id;
include/sys/thread.h
+6
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@@ -6,8 +6,14 @@ struct thread {
uintptr_t rsp0; // 0x00
uintptr_t syscall_rsp; // 0x08
uintptr_t rsp0_top; // 0x10
uintptr_t cr3; // 0x18
uintptr_t rsp0_base;
size_t rsp0_size;
uintptr_t rsp3_base;
size_t rsp3_size;
} data;
int pid;
sys/amd64/sched_s.S
+18
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@@ -1,3 +1,4 @@
#include "sys/amd64/asm/asm_cpu.h"
.section .text
.global context_enter
context_enter:
@@ -40,5 +41,22 @@ context_switch_first:
popq %r14
popq %r15
// Load TSS.RSP0 for user -> kernel transition
// %rax = top of task's stack
movq 0x10(%rdi), %rax
// %rcx = &tss
movq get_cpu(0x10), %rcx
// &tss->rsp0 = %rax
movq %rax, 4(%rcx)
// Load new %cr3 if changed
movq 0x18(%rdi), %rax
movq %cr3, %rcx
test %rcx, %rax
jz 1f
// Only load if cr3 != thr->cr3
movq %rax, %cr3
1:
ret
.size context_switch_to, . - context_switch_to
sys/debug.c
+5
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@@ -61,6 +61,11 @@ void debug_backtrace(uintptr_t rbp, int depth, int limit) {
return;
}
if ((rbp & 0xFFFFFF0000000000) != 0xFFFFFF0000000000) {
kfatal("-- %rbp is not from kernel space\n");
return;
}
uintptr_t rip = ((uintptr_t *) rbp)[1];
uintptr_t rbp_next = ((uintptr_t *) rbp)[0];
sys/sched.c
+126 -3
View File
@@ -1,6 +1,8 @@
#include "sys/amd64/mm/phys.h"
#include "sys/amd64/mm/pool.h"
#include "sys/amd64/hw/irq.h"
#include "sys/amd64/hw/idt.h"
#include "sys/amd64/cpu.h"
#include "sys/assert.h"
#include "sys/thread.h"
#include "sys/debug.h"
@@ -73,6 +75,8 @@ static void init_thread(struct thread *thr, void *(*entry)(void *), void *arg) {
thr->data.rsp0_base = MM_VIRTUALIZE(stack_pages);
thr->data.rsp0_size = MM_PAGE_SIZE;
thr->data.cr3 = MM_PHYS(mm_kernel);
uint64_t *stack = (uint64_t *) (thr->data.rsp0_base + thr->data.rsp0_size);
// Initial thread context
@@ -143,6 +147,99 @@ static void init_thread(struct thread *thr, void *(*entry)(void *), void *arg) {
thr->data.rsp0 = (uintptr_t) stack;
}
static void init_user(struct thread *thr, void *(*entry)(void *), void *arg) {
uintptr_t stack_pages = amd64_phys_alloc_page();
_assert(stack_pages != MM_NADDR);
uintptr_t stack3_pages = amd64_phys_alloc_page();
_assert(stack3_pages != MM_NADDR);
thr->data.rsp0_base = MM_VIRTUALIZE(stack_pages);
thr->data.rsp0_size = MM_PAGE_SIZE;
thr->data.rsp0_top = thr->data.rsp0_base + thr->data.rsp0_size;
thr->data.rsp3_base = MM_VIRTUALIZE(stack3_pages);
thr->data.rsp3_size = MM_PAGE_SIZE;
mm_space_t space = amd64_mm_pool_alloc();
mm_space_clone(space, mm_kernel, MM_CLONE_FLG_KERNEL);
thr->data.cr3 = MM_PHYS(space);
// Allow this thread to access upper pages for testing
space[AMD64_MM_STRIPSX(KERNEL_VIRT_BASE) >> 39] |= MM_PAGE_USER;
uint64_t *pdpt = (uint64_t *) MM_VIRTUALIZE(space[AMD64_MM_STRIPSX(KERNEL_VIRT_BASE) >> 39] & ~0xFFF);
for (uint64_t i = 0; i < 4; ++i) {
pdpt[((AMD64_MM_STRIPSX(KERNEL_VIRT_BASE) >> 30) + i) & 0x1FF] |= MM_PAGE_USER;
}
uint64_t *stack = (uint64_t *) (thr->data.rsp0_base + thr->data.rsp0_size);
// Initial thread context
// Entry context
// ss
*--stack = 0x1B;
// rsp
*--stack = thr->data.rsp3_base + thr->data.rsp3_size;
// rflags
*--stack = 0x200;
// cs
*--stack = 0x23;
// rip
*--stack = (uintptr_t) entry;
// Caller-saved
// r11
*--stack = 0;
// r10
*--stack = 0;
// r9
*--stack = 0;
// r8
*--stack = 0;
// rcx
*--stack = 0;
// rdx
*--stack = 0;
// rsi
*--stack = 0;
// rdi
*--stack = (uintptr_t) arg;
// rax
*--stack = 0;
// Small stub so that context switch enters the thread properly
*--stack = (uintptr_t) context_enter;
// Callee-saved
// r15
*--stack = 0;
// r14
*--stack = 0;
// r13
*--stack = 0;
// r12
*--stack = 0;
// rbp
*--stack = 0;
// rbx
*--stack = 0;
// Thread lifecycle:
// * context_switch_to():
// - pops callee-saved registers (initializing them to 0)
// - enters context_enter()
// * context_enter():
// - pops caller-saved registers (initializing them to 0 and setting up rdi)
// - enters proper execution context via iret
// ... Thread is running here until it yields
// * yield leads to context_switch_to():
// - call to yield() automatically (per ABI) stores caller-saved registers
// - context_switch_to() pushes callee-saved registers onto current stack
// - selects a new thread
// - step one
thr->data.rsp0 = (uintptr_t) stack;
}
static void *idle(void *arg) {
while (1) {
asm volatile ("hlt");
@@ -151,14 +248,17 @@ static void *idle(void *arg) {
}
static void *t0(void *arg) {
uint16_t *ptr = (uint16_t *) MM_VIRTUALIZE(0xB8000 + (uint64_t) arg * 2);
size_t cntr = 0;
*ptr = 0;
while (1) {
for (size_t i = 0; i < 10000000; ++i);
*((uint16_t *) MM_VIRTUALIZE(0xB8000 + (uint64_t) arg * 2)) ^= 'A';
*ptr ^= 'A' | 0x700;
++cntr;
if (cntr == 50 * (((uint64_t) arg) +1)) {
if (cntr == 20 * (((uint64_t) arg) +1)) {
kdebug("[%d] Død\n", arg);
sched_unqueue(thread_current);
}
@@ -166,6 +266,17 @@ static void *t0(void *arg) {
return 0;
}
static void *u0(void *arg) {
uint16_t *ptr = (uint16_t *) MM_VIRTUALIZE(0xB8000 + (uint64_t) arg * 2);
*ptr = 0;
while (1) {
for (size_t i = 0; i < 10000000; ++i);
*ptr ^= 'A' | 0x1200;
}
return 0;
}
void yield(void) {
struct thread *from = thread_current;
struct thread *to;
@@ -183,12 +294,16 @@ void yield(void) {
}
static struct thread t_n[3] = {0};
static struct thread t_u[3] = {0};
void sched_init(void) {
init_thread(&t_n[0], t0, (void *) 0);
init_thread(&t_n[1], t0, (void *) 1);
init_thread(&t_n[2], t0, (void *) 2);
init_thread(&thread_idle, idle, NULL);
init_user(&t_u[0], u0, (void *) 5);
init_user(&t_u[1], u0, (void *) 6);
init_user(&t_u[2], u0, (void *) 7);
init_thread(&thread_idle, idle, 0);
thread_idle.pid = -1;
@@ -196,9 +311,17 @@ void sched_init(void) {
t_n[1].pid = 2;
t_n[2].pid = 3;
t_u[0].pid = 10;
t_u[1].pid = 11;
t_u[2].pid = 12;
sched_queue(&t_n[0]);
sched_queue(&t_n[1]);
sched_queue(&t_n[2]);
sched_queue(&t_u[0]);
sched_queue(&t_u[1]);
sched_queue(&t_u[2]);
}
void sched_enter(void) {