# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1311521364 -10800
# Node ID e6de3c6015cb26d28900e0235e0baf8c5325bacd
# Parent  928b0ebfff4ddb3222b0c73c279d93c93cb568e9
started implementing processes

diff -r 928b0ebfff4d -r e6de3c6015cb src/asmops.h
--- a/src/asmops.h	Tue Jun 14 01:19:07 2011 +0300
+++ b/src/asmops.h	Sun Jul 24 18:29:24 2011 +0300
@@ -1,6 +1,12 @@
 #ifndef ASMOPS_H_
 #define ASMOPS_H_
 
+/* general purpose registers as they are pushed by pusha */
+struct registers {
+	uint32_t edi, esi, ebp, esp;
+	uint32_t ebx, edx, ecx, eax;
+} __attribute__ ((packed));
+
 #define enable_intr() asm volatile("sti")
 #define disable_intr() asm volatile("cli")
 #define halt_cpu() asm volatile("hlt")
diff -r 928b0ebfff4d -r e6de3c6015cb src/intr.c
--- a/src/intr.c	Tue Jun 14 01:19:07 2011 +0300
+++ b/src/intr.c	Sun Jul 24 18:29:24 2011 +0300
@@ -40,12 +40,13 @@
  */
 struct intr_frame {
 	/* registers pushed by pusha in intr_entry_* */
-	uint32_t edi, esi, ebp, esp;
-	uint32_t ebx, edx, ecx, eax;
+	struct registers regs;
 	/* interrupt number and error code pushed in intr_entry_* */
 	uint32_t inum, err;
 	/* pushed by CPU during interrupt entry */
 	uint32_t eip, cs, eflags;
+	/* pushed by CPU during interrupt entry from user space */
+	uint32_t esp, ss;
 };
 
 
diff -r 928b0ebfff4d -r e6de3c6015cb src/proc.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/proc.c	Sun Jul 24 18:29:24 2011 +0300
@@ -0,0 +1,37 @@
+#include "proc.h"
+#include "tss.h"
+
+static struct process proc[MAX_PROC];
+static int cur_pid;
+
+void init_proc(void)
+{
+	cur_pid = -1;
+
+	/* prepare the first process */
+
+	/* create the virtual address space for this process */
+
+	/* allocate a chunk of memory for the process image
+	 * and copy the code of test_proc there.
+	 * (should be mapped at a fixed address)
+	 */
+
+	/* fill in the proc[0].ctx with the appropriate process stack
+	 * and instruction pointers
+	 */
+
+	/* switch to it by calling a function that takes the context
+	 * of the current process, plugs the values into the interrupt
+	 * stack, and calls iret.
+	 * (should also set ss0/sp0 in TSS before returning)
+	 */
+}
+
+void save_context(struct intr_frame *ifrm)
+{
+	proc[cur_pid].ctx->regs = ifrm->regs;
+	proc[cur_pid].ctx->instr_ptr = ifrm->eip;
+	proc[cur_pid].ctx->stack_ptr = ifrm->esp;
+	proc[cur_pid].ctx->flags = ifrm->eflags;
+}
diff -r 928b0ebfff4d -r e6de3c6015cb src/proc.h
--- a/src/proc.h	Tue Jun 14 01:19:07 2011 +0300
+++ b/src/proc.h	Sun Jul 24 18:29:24 2011 +0300
@@ -1,14 +1,21 @@
 #ifndef PROC_H_
 #define PROC_H_
 
-#include "tss.h"
+#include "asmops.h"
+
+#define MAX_PROC	128
+
+struct context {
+	struct registers regs;
+	uint32_t instr_ptr;
+	uint32_t stack_ptr;
+	uint32_t flags;
+	/* TODO add FPU state */
+};
+
 
 struct process {
-	int id;
-
-	struct task_state tss;
-
-	struct process *next;
+	struct context ctx;
 };
 
 #endif	/* PROC_H_ */