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update for mooc OS labs

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This commit is contained in:
yuchen
2015-01-30 20:20:30 +08:00
parent 6a4eb1f465
commit 87059df293
57 changed files with 586 additions and 129 deletions
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32
labcodes_answer/lab1_result/kern/trap/trap.c
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@@ -8,7 +8,7 @@
#include <assert.h>
#include <console.h>
#include <kdebug.h>
#include <string.h>
#define TICK_NUM 100
static void print_ticks() {
@@ -51,6 +51,9 @@ idt_init(void) {
for (i = 0; i < sizeof(idt) / sizeof(struct gatedesc); i ++) {
SETGATE(idt[i], 0, GD_KTEXT, __vectors[i], DPL_KERNEL);
}
// set for switch from user to kernel
SETGATE(idt[T_SWITCH_TOK], 0, GD_KTEXT, __vectors[T_SWITCH_TOK], DPL_USER);
// load the IDT
lidt(&idt_pd);
}
@@ -140,6 +143,9 @@ print_regs(struct pushregs *regs) {
cprintf(" eax 0x%08x\n", regs->reg_eax);
}
/* temporary trapframe or pointer to trapframe */
struct trapframe switchk2u, *switchu2k;
/* trap_dispatch - dispatch based on what type of trap occurred */
static void
trap_dispatch(struct trapframe *tf) {
@@ -168,8 +174,30 @@ trap_dispatch(struct trapframe *tf) {
break;
//LAB1 CHALLENGE 1 : YOUR CODE you should modify below codes.
case T_SWITCH_TOU:
if (tf->tf_cs != USER_CS) {
switchk2u = *tf;
switchk2u.tf_cs = USER_CS;
switchk2u.tf_ds = switchk2u.tf_es = switchk2u.tf_ss = USER_DS;
switchk2u.tf_esp = (uint32_t)tf + sizeof(struct trapframe) - 8;
// set eflags, make sure ucore can use io under user mode.
// if CPL > IOPL, then cpu will generate a general protection.
switchk2u.tf_eflags |= FL_IOPL_MASK;
// set temporary stack
// then iret will jump to the right stack
*((uint32_t *)tf - 1) = (uint32_t)&switchk2u;
}
break;
case T_SWITCH_TOK:
panic("T_SWITCH_** ??\n");
if (tf->tf_cs != KERNEL_CS) {
tf->tf_cs = KERNEL_CS;
tf->tf_ds = tf->tf_es = KERNEL_DS;
tf->tf_eflags &= ~FL_IOPL_MASK;
switchu2k = (struct trapframe *)(tf->tf_esp - (sizeof(struct trapframe) - 8));
memmove(switchu2k, tf, sizeof(struct trapframe) - 8);
*((uint32_t *)tf - 1) = (uint32_t)switchu2k;
}
break;
case IRQ_OFFSET + IRQ_IDE1:
case IRQ_OFFSET + IRQ_IDE2: