🔧 使用C语言重写了设置中断门的代码。

This commit is contained in:
fslongjin 2022-01-26 18:04:33 +08:00
parent 06cfb1ceb9
commit ba7f1bb4ea
2 changed files with 32 additions and 59 deletions

View File

@ -24,64 +24,37 @@ extern struct desc_struct GDT_Table[]; //GDT_Table是head.S中的GDT_Table
extern struct gate_struct IDT_Table[]; //IDT_Table是head.S中的IDT_Table extern struct gate_struct IDT_Table[]; //IDT_Table是head.S中的IDT_Table
extern unsigned int TSS64_Table[26]; extern unsigned int TSS64_Table[26];
/** /**
* @brief 16B * @brief 16B
* @param gate_selector_addr IDT表项的地址 * @param gate_selector_addr IDT表项的地址
* @param attr PDPLTYPE的属性 * @param attr PDPLTYPE的属性
* @param ist * @param ist
* @param code_addr * @param code_addr
*/ */
// todo:在系统异常处理主功能完成后将这段代码用C来写一遍。这段汇编实在是太晦涩难懂了我看了半个钟才看明白。 void set_gate(ul *gate_selector_addr, ul attr, unsigned char ist, ul *code_addr)
{
ul __d0=0, __d1=0;
ul tmp_code_addr = *code_addr;
__d0 = attr << 40; //设置P、DPL、Type
/* __d0 |= ((ul)(ist) << 32); // 设置ist
#define _set_gate(gate_selector_addr, attr, ist, code_addr) \
do{ \ __d0 |= 8 << 16; //设置段选择子为0x1000
unsigned long __d0, __d1; \
__asm__ __volatile__ ( "movw %%dx, %%ax \n\t" \ __d0 |= (0xffff & tmp_code_addr); //设置段内偏移的[15:00]
"andq $0x7, %%rcx \n\t" // 清空rcx中除了2:0以外的所有位 此前ist的值已经被赋给了rcx \
"addq %4, %%rcx \n\t" // 将P,DPL, Type的值加到rcx中 \ tmp_code_addr >>= 16;
"shlq $32, %%rcx \n\t" \ __d0 |= (0xffff & tmp_code_addr) << 48; // 设置段内偏移[31:16]
"addq %%rcx, %%rax \n\t" // 设置ist \
"xorq %%rcx, %%rcx \n\t" // 清空rcx \ tmp_code_addr >>= 16;
"movl %%edx, %%ecx \n\t" \
"shrq $16, %%ecx \n\t" \ __d1 = (0xffffffff & tmp_code_addr); //设置段内偏移[63:32]
"shlq $48, %%rcx \n\t" // 左移到低8B中表示段内偏移的[31:16]处 \
"addq %%rcx, %%rax \n\t" // 设置段内偏移[31:16] \
"movq %%rax, %0 \n\t" // 输出到门选择子的低8B \ *gate_selector_addr = __d0;
"shrq $32, %%rdx \n\t" \ *(gate_selector_addr + 1) = __d1;
"movq %%rdx, %1 \n\t" // 输出到门选择子的高8B \ }
:"=m"(*((unsigned long *)(gate_selector_addr))) , \
"=m"(*(1 + (unsigned long *)(gate_selector_addr))),"=&a"(__d0),"=&d"(__d1) \
:"i"(attr << 8), \
"3"((unsigned long *)(code_addr)),"2"(0x8 << 16),"c"(ist) \
:"memory" \
); \
}while(0)
*/
//由于带上注释就编译不过,因此复制一份到这里
#define _set_gate(gate_selector_addr, attr, ist, code_addr) \
do \
{ \
unsigned long __d0, __d1; \
__asm__ __volatile__("movw %%dx, %%ax \n\t" \
"andq $0x7, %%rcx \n\t" \
"addq %4, %%rcx \n\t" \
"shlq $32, %%rcx \n\t" \
"addq %%rcx, %%rax \n\t" \
"xorq %%rcx, %%rcx \n\t" \
"movl %%edx, %%ecx \n\t" \
"shrq $16, %%rcx \n\t" \
"shlq $48, %%rcx \n\t" \
"addq %%rcx, %%rax \n\t" \
"movq %%rax, %0 \n\t" \
"shrq $32, %%rdx \n\t" \
"movq %%rdx, %1 \n\t" \
: "=m"(*((unsigned long *)(gate_selector_addr))), \
"=m"(*(1 + (unsigned long *)(gate_selector_addr))), "=&a"(__d0), "=&d"(__d1) \
: "i"(attr << 8), \
"3"((unsigned long *)(code_addr)), "2"(0x8 << 16), "c"(ist) \
: "memory"); \
} while (0)
/** /**
* @brief * @brief
@ -103,7 +76,7 @@ do{ \
*/ */
void set_intr_gate(unsigned int n, unsigned char ist, void *addr) void set_intr_gate(unsigned int n, unsigned char ist, void *addr)
{ {
_set_gate(IDT_Table + n, 0x8E, ist, addr); // p=1DPL=0, type=E set_gate(IDT_Table + n, 0x8E, ist, &addr); // p=1DPL=0, type=E
} }
/** /**
@ -115,7 +88,7 @@ void set_intr_gate(unsigned int n, unsigned char ist, void *addr)
*/ */
void set_trap_gate(unsigned int n, unsigned char ist, void *addr) void set_trap_gate(unsigned int n, unsigned char ist, void *addr)
{ {
_set_gate(IDT_Table + n, 0x8F, ist, addr); // p=1DPL=0, type=F set_gate(IDT_Table + n, 0x8F, ist, &addr); // p=1DPL=0, type=F
} }
/** /**
@ -127,7 +100,7 @@ void set_trap_gate(unsigned int n, unsigned char ist, void *addr)
*/ */
void set_system_trap_gate(unsigned int n, unsigned char ist, void *addr) void set_system_trap_gate(unsigned int n, unsigned char ist, void *addr)
{ {
_set_gate(IDT_Table + n, 0xEF, ist, addr); // p=1DPL=3, type=F set_gate(IDT_Table + n, 0xEF, ist, &addr); // p=1DPL=3, type=F
} }
/** /**