From f4c3fb30b762724ca8fc09602ea05474d967cf42 Mon Sep 17 00:00:00 2001
From: Mark <alnyan@airmail.cc>
Date: Mon, 30 Sep 2019 12:10:33 +0300
Subject: [PATCH] [amd64] Move kidle init to a function

---
 include/sys/thread.h   |  9 ++++++-
 sys/amd64/sys/kidle.c  | 37 ++++++++-------------------
 sys/amd64/sys/thread.c | 57 ++++++++++++++++++++++++++++++++++++------
 3 files changed, 67 insertions(+), 36 deletions(-)

diff --git a/include/sys/thread.h b/include/sys/thread.h
index cd25cfa..ddc88e2 100644
--- a/include/sys/thread.h
+++ b/include/sys/thread.h
@@ -55,7 +55,14 @@ int thread_info_init(thread_info_t *info);
  * @brief Setup thread data structures
  * @param t Thread
  */
-int thread_init(thread_t *t);
+int thread_init(thread_t *t,
+                mm_space_t space,
+                uintptr_t ip,
+                uintptr_t kstack_base,
+                size_t kstack_size,
+                uintptr_t ustack_base,
+                size_t ustack_size,
+                uint32_t flags);
 
 /**
  * @brief Set thread instruction pointer
diff --git a/sys/amd64/sys/kidle.c b/sys/amd64/sys/kidle.c
index 6fa6501..b78939c 100644
--- a/sys/amd64/sys/kidle.c
+++ b/sys/amd64/sys/kidle.c
@@ -1,4 +1,5 @@
 #include "sys/thread.h"
+#include "sys/assert.h"
 #include "sys/sched.h"
 #include "sys/kidle.h"
 #include "sys/debug.h"
@@ -8,38 +9,20 @@ static char kidle_kstack[8192];
 static thread_t kidle_thread;
 
 static void kidle(void) {
-    // Debug: print time ~each second
-    uint32_t v_p = 0;
     while (1) {
-        uint32_t v = systick / SYSTICK_RES;
-        if (v != v_p) {
-            kdebug("%d\n", v);
-            v_p = v;
-        }
         asm volatile ("sti; hlt");
     }
 }
 
 void kidle_init(void) {
-    // TODO: functions for thread creation including kthread creation
-    thread_info_init(&kidle_thread.info);
-
-    kidle_thread.info.flags = THREAD_KERNEL;
-
-    kidle_thread.kstack_base = (uintptr_t) kidle_kstack;
-    kidle_thread.kstack_size = 4096;
-    kidle_thread.kstack_ptr = kidle_thread.kstack_base + kidle_thread.kstack_size - sizeof(amd64_thread_context_t);
-
-    amd64_thread_context_t *ctx = (amd64_thread_context_t *) kidle_thread.kstack_ptr;
-
-    ctx->cr3 = (uintptr_t) mm_kernel - 0xFFFFFF0000000000;
-    ctx->rip = (uintptr_t) kidle;
-    ctx->cs = 0x08;
-    ctx->ss = 0x10;
-    ctx->rsp = kidle_thread.kstack_ptr;
-    ctx->rflags = 0x248;
-
-    kidle_thread.next = NULL;
-
+    assert(thread_init(&kidle_thread,
+                       mm_kernel,
+                       (uintptr_t) kidle,
+                       (uintptr_t) kidle_kstack,
+                       sizeof(kidle_kstack),
+                       0,
+                       0,
+                       THREAD_KERNEL) == 0,
+           "Failed to set kidle up\n");
     sched_add(&kidle_thread);
 }
diff --git a/sys/amd64/sys/thread.c b/sys/amd64/sys/thread.c
index f369a4d..252ac94 100644
--- a/sys/amd64/sys/thread.c
+++ b/sys/amd64/sys/thread.c
@@ -4,21 +4,62 @@
 #include "sys/debug.h"
 #include "sys/heap.h"
 
+#define AMD64_DEFAULT_KSTACK_SIZE   0x4000
+
 #define ctx0(t)    ((amd64_thread_context_t *) (t->kstack_ptr))
 
-int thread_init(thread_t *t) {
+int thread_init(thread_t *t,
+                mm_space_t space,
+                uintptr_t ip,
+                uintptr_t kstack_base,
+                size_t kstack_size,
+                uintptr_t ustack_base,
+                size_t ustack_size,
+                uint32_t flags
+        ) {
     if (thread_info_init(&t->info) != 0) {
         return -1;
     }
+    t->info.flags = flags;
 
-    // t->kstack_base = (uintptr_t) kmalloc(sizeof(amd64_thread_context_t));
-    // // TODO: assert
-    // if (!t->kstack_base) {
-    //     panic("Failed to allocate thread stack\n");
-    // }
+    // Mandatory for both kernel and user threads
+    if (!kstack_base) {
+        kstack_base = (uintptr_t) kmalloc(AMD64_DEFAULT_KSTACK_SIZE);
+        kstack_size = AMD64_DEFAULT_KSTACK_SIZE;
+        if (!kstack_base) {
+            panic("Failed to allocate thread kstack\n");
+        }
+    }
+    t->kstack_base = kstack_base;
+    t->kstack_size = kstack_size;
+    t->kstack_ptr = t->kstack_base + t->kstack_size - sizeof(amd64_thread_context_t);
 
-    // t->kstack_size = sizeof(amd64_thread_context_t);
-    // t->kstack_ptr = t->kstack_base + t->kstack_size;
+    // If we're not kernel, additionally set the ustack
+    if (!(flags & THREAD_KERNEL)) {
+        assert(ustack_base, "Tried to create an userspace task, but passed no ustack\n");
+
+        panic("Not implemented\n");
+    }
+
+    // Set CS:RIP
+    if (flags & THREAD_KERNEL) {
+        ctx0(t)->cs = 0x08;
+        ctx0(t)->ss = 0x10;
+        ctx0(t)->rsp = t->kstack_ptr;
+        ctx0(t)->rflags = 0x248;
+        ctx0(t)->rip = ip;
+    } else {
+        panic("Not implemented\n");
+    }
+
+    assert(((uintptr_t) space) > 0xFFFFFF0000000000,
+           "Invalid PML4 address provided: %p\n", space);
+
+    // Set task space
+    t->info.space = space;
+    ctx0(t)->cr3 = ((uintptr_t) space) - 0xFFFFFF0000000000;
+
+    t->next = NULL;
 
     return 0;
 }