Implement multitasking.

3 files changed, 44 insertions, 5 deletions

diff --git a/kernel/include/idt.h b/kernel/include/idt.h
index 9415c8e..8e84cea 100644
--- a/kernel/include/idt.h
+++ b/kernel/include/idt.h
@@ -60,13 +60,12 @@
 
 #define EFLAGS_IF		(0x1 << 9)
 
-struct registers {
+typedef struct registers {
 	uint32_t ds;                  // Data segment selector
 	uint32_t edi, esi, ebp, useless_esp, ebx, edx, ecx, eax; // Pushed by pusha.
 	uint32_t int_no, err_code;    // Interrupt number and error code (if applicable)
 	uint32_t eip, cs, eflags, esp, ss; // Pushed by the processor automatically.
-};
-typedef struct registers registers_t;
+} registers_t;
 
 typedef void (*isr_handler_t)(registers_t*);
 
diff --git a/kernel/include/region.h b/kernel/include/region.h
index ac68047..b45a85d 100644
--- a/kernel/include/region.h
+++ b/kernel/include/region.h
@@ -34,8 +34,6 @@ region_info_t *find_region(void* addr);
 void region_free(void* addr);
 
 // some usefull PF handlers
-// stack_pf_handler : allocates new frames and panics on access to first page of region (stack overflow)
-void stack_pf_handler(pagedir_t *pd, struct region_info *r, void* addr);
 // default_allocator_pf_handler : just allocates new frames on page faults
 void default_allocator_pf_handler(pagedir_t *pd, struct region_info *r, void* addr);
 
diff --git a/kernel/include/task.h b/kernel/include/task.h
new file mode 100644
index 0000000..8ba50b0
--- /dev/null
+++ b/kernel/include/task.h
@@ -0,0 +1,42 @@
+#pragma once
+
+#include <sys.h>
+#include <region.h>
+
+#define T_STATE_RUNNING		1
+#define T_STATE_FINISHED	2
+#define T_STATE_WAITING		3
+
+#define KPROC_STACK_SIZE 0x8000	// 8Kb
+
+typedef struct saved_context {
+	uint32_t *esp;
+	void (*eip)();
+} saved_context_t;
+
+typedef struct task {
+	saved_context_t ctx;
+
+	uint32_t state;
+	void* result;
+	bool has_result;
+
+	region_info_t *stack_region;
+
+	void* more_data;
+
+	struct task *next_in_queue;
+} task_t;
+
+typedef void (*entry_t)(void*);
+
+void tasking_setup(entry_t cont, void* data);		// never returns
+task_t *new_task(entry_t entry);	// task is PAUSED, and must be resume_with_result'ed
+extern task_t *current_task;
+
+
+void yield();
+void* wait_for_result();
+void resume_with_result(task_t *task, void* data, bool run_at_once);
+
+/* vim: set ts=4 sw=4 tw=0 noet :*/