From c808a5d2958279af1d2a2d6f666bd3f1e38c01c5 Mon Sep 17 00:00:00 2001
From: Ruslan Isaev <ubijca16@gmail.com>
Date: Thu, 29 May 2025 21:18:09 +0300
Subject: [PATCH] fix creating ring 3 tasks finally

---
 src/tasking/switch.asm | 19 ++++++++-------
 src/tasking/task.c     | 52 +++++++++++++++++++++++++-----------------
 2 files changed, 40 insertions(+), 31 deletions(-)

diff --git a/src/tasking/switch.asm b/src/tasking/switch.asm
index acdfa9c..12e79ca 100644
--- a/src/tasking/switch.asm
+++ b/src/tasking/switch.asm
@@ -15,29 +15,28 @@ global switchProcess
 extern current
 extern trapret
 
+; void switchProcess(Process* next_process_ptr)
 switchProcess:
-    mov eax, [esp + 4] ; eax = old
-    mov edx, [esp + 8] ; edx = new
+    mov edx, [esp + 4]      ; edx = next_process_ptr (получаем аргумент СРАЗУ)
+    cli                     ; Запретить прерывания
 
     push ebp
     push ebx
     push esi
     push edi
 
-    mov [eax+4], esp
-    mov esp, [edx+4]
+    mov eax, [current]
+    mov [eax + 4], esp      ; current->kesp = esp
 
-    ;mov eax, [edx+12]
-    ;sub eax, 0xC0000000
-    ;mov cr3, eax
+    ; edx уже содержит next_process_ptr
+    mov esp, [edx + 4]      ; esp = next_process_ptr->kesp
+    mov [current], edx      ; current = next_process_ptr
 
     pop edi
     pop esi
     pop ebx
     pop ebp
-
-
-    ret                  ; Для ring 0 просто возвращаемся
+    ret
 
 
 trapret:
diff --git a/src/tasking/task.c b/src/tasking/task.c
index a109b90..58846b3 100644
--- a/src/tasking/task.c
+++ b/src/tasking/task.c
@@ -32,44 +32,54 @@ static void processStartup()
 
 Process* task_create(uint32_t func, void** args, uint32_t arg_count, uint32_t ring)
 {
-    Process* p = alloc_page();//heap_alloc(sizeof(Process));
+    Process* p = (Process*)alloc_page();//heap_alloc(sizeof(Process));
+    memset(p, 0, sizeof(Process));
     p->pid = ++pid_counter;
     p->state = Ready;
     p->ring = ring;
 
     // Выделяем стек ядра
-    p->kstack = alloc_page();//heap_alloc(KSTACKSIZE);
-    map_page(p->kstack, p->kstack, 0x7);
+    p->kstack = (char*)alloc_page();//heap_alloc(KSTACKSIZE);
+    map_page(p->kstack, p->kstack, 0x3);
     printf("kstack: %X!!!!!!!!!!!!\n", p->kstack);
-    uint8_t* sp = (uint8_t*)(p->kstack);
+    uint8_t* sp = (uint8_t*)(p->kstack + KSTACKSIZE);
 
     
 
     sp -= sizeof(TrapFrame);
     p->tf = (TrapFrame*)sp;
     memset(p->tf, 0, sizeof(TrapFrame));
-    p->tf->cs = ring == 3 ? (SEG_UCODE) | DPL_USER : (SEG_KCODE);
-    p->tf->ds = ring == 3 ? (SEG_UDATA) | DPL_USER : (SEG_KDATA);
+
+    p->tf->cs = ring == 3 ? (SEG_UCODE | DPL_USER) : (SEG_KCODE);
+    p->tf->ds = ring == 3 ? (SEG_UDATA | DPL_USER) : (SEG_KDATA);
     p->tf->es = p->tf->ds;
     p->tf->fs = p->tf->ds;
     p->tf->gs = p->tf->ds;
-    p->tf->usermode_ss = p->tf->ds;
+
+    p->tf->usermode_ss = ring == 3 ? (SEG_UDATA | DPL_USER) : (SEG_KDATA);
+
     p->tf->eflags = FL_IF;
     p->tf->eip = (uint32_t)func;
-    p->tf->usermode_esp = 0x800000; // Предполагаем, что пользовательский стек настроен
+
+    if(ring == 3)
+    {
+        void* user_stack_physical = alloc_page();
+
+        uint32_t user_stack_virtual_top = 0xBFFFF000 - ((p->pid -1) * (USTACKSIZE + 4096)); // Уникальный верх стека для каждого процесса
+        uint32_t user_stack_virtual_base = user_stack_virtual_top - USTACKSIZE;
+
+        map_page(user_stack_physical, (void*)user_stack_virtual_base, 0x7/*PTE_PRESENT | PTE_READ_WRITE | PTE_USER*/); // Флаги 0x7
+
+    }
 
     sp -= sizeof(Context);
     p->context = (Context*)sp;
-    p->context->eip = (uint32_t)trapret;
-	// Настраиваем начальный контекст
-    //sp -= 5; // Место для edi, esi, ebx, ebp, eip
-    //sp -= sizeof(Context);
-    p->context->edi = 0;
-    p->context->esi = 0;
-    p->context->ebx = 0;
-    p->context->ebp = 0;
+    memset(p->context, 0, sizeof(Context));
 
-    p->page_directory = kernel_page_directory;
+    p->context->eip = (uint32_t)trapret;
+    p->kesp = (uint32_t)sp;
+
+    p->page_directory = kpage_dir;
 
     p->next = 0;
 
@@ -111,7 +121,7 @@ void schedule()
     if (next != current)
     {
         //loadPageDirectory(next->page_directory);
-        printf("switching to %X\n", next->pid);
+        //printf("switching to %X\n", next->pid);
         switchProcess(next);
     }
 }
@@ -142,10 +152,10 @@ void scheduler_init()
     task_create((uint32_t)idle, NULL, 0, 0);
 
     void* args1[] = {(void*)42, (void*)"ebalo"};
-    //task_create((EntryPoint)task1, args1, 2, 0);
+    task_create((uint32_t)task1, args1, 2, 0);
     void* args2[] = {(void*)69, (void*)420};
     //task_create((EntryPoint)&task2, args2, 2, 0);
-	//jump_usermode2();
+	jump_usermode2();
 }
 
 #include "../include/string.h"
@@ -211,7 +221,7 @@ void jump_usermode2(void) {
        (code_pte & 0x4) ? "user" : "supervisor");
 	
 	task_create((uint32_t)user_code_virt, NULL, 0, 3);
-	//task_create(second_user_code_virt, NULL, 0, 3);
+	task_create((uint32_t)second_user_code_virt, NULL, 0, 3);
 
 	return;
     // Switch to user mode with interrupts enabled