1 #ifndef _X86_DESC_H_ 2 #define _X86_DESC_H_ 3 4 #include <setjmp.h> 5 6 void setup_idt(void); 7 void setup_alt_stack(void); 8 9 struct ex_regs { 10 unsigned long rax, rcx, rdx, rbx; 11 unsigned long dummy, rbp, rsi, rdi; 12 #ifdef __x86_64__ 13 unsigned long r8, r9, r10, r11; 14 unsigned long r12, r13, r14, r15; 15 #endif 16 unsigned long vector; 17 unsigned long error_code; 18 unsigned long rip; 19 unsigned long cs; 20 unsigned long rflags; 21 #ifdef __x86_64__ 22 unsigned long rsp; 23 unsigned long ss; 24 #endif 25 }; 26 27 typedef void (*handler)(struct ex_regs *regs); 28 29 typedef struct { 30 u16 prev; 31 u16 res1; 32 u32 esp0; 33 u16 ss0; 34 u16 res2; 35 u32 esp1; 36 u16 ss1; 37 u16 res3; 38 u32 esp2; 39 u16 ss2; 40 u16 res4; 41 u32 cr3; 42 u32 eip; 43 u32 eflags; 44 u32 eax, ecx, edx, ebx, esp, ebp, esi, edi; 45 u16 es; 46 u16 res5; 47 u16 cs; 48 u16 res6; 49 u16 ss; 50 u16 res7; 51 u16 ds; 52 u16 res8; 53 u16 fs; 54 u16 res9; 55 u16 gs; 56 u16 res10; 57 u16 ldt; 58 u16 res11; 59 u16 t:1; 60 u16 res12:15; 61 u16 iomap_base; 62 } tss32_t; 63 64 typedef struct __attribute__((packed)) { 65 u32 res1; 66 u64 rsp0; 67 u64 rsp1; 68 u64 rsp2; 69 u64 res2; 70 u64 ist1; 71 u64 ist2; 72 u64 ist3; 73 u64 ist4; 74 u64 ist5; 75 u64 ist6; 76 u64 ist7; 77 u64 res3; 78 u16 res4; 79 u16 iomap_base; 80 } tss64_t; 81 82 #ifdef __x86_64 83 #define ASM_TRY(catch) \ 84 "movl $0, %%gs:4 \n\t" \ 85 ".pushsection .data.ex \n\t" \ 86 ".quad 1111f, " catch "\n\t" \ 87 ".popsection \n\t" \ 88 "1111:" 89 #else 90 #define ASM_TRY(catch) \ 91 "movl $0, %%gs:4 \n\t" \ 92 ".pushsection .data.ex \n\t" \ 93 ".long 1111f, " catch "\n\t" \ 94 ".popsection \n\t" \ 95 "1111:" 96 #endif 97 98 /* 99 * selector 32-bit 64-bit 100 * 0x00 NULL descriptor NULL descriptor 101 * 0x08 ring-0 code segment (32-bit) ring-0 code segment (64-bit) 102 * 0x10 ring-0 data segment (32-bit) ring-0 data segment (32/64-bit) 103 * 0x18 ring-0 code segment (P=0) ring-0 code segment (64-bit, P=0) 104 * 0x20 intr_alt_stack TSS ring-0 code segment (32-bit) 105 * 0x28 ring-0 code segment (16-bit) same 106 * 0x30 ring-0 data segment (16-bit) same 107 * 0x38 (0x3b) ring-3 code segment (32-bit) same 108 * 0x40 (0x43) ring-3 data segment (32-bit) ring-3 data segment (32/64-bit) 109 * 0x48 (0x4b) **unused** ring-3 code segment (64-bit) 110 * 0x50-0x78 free to use for test cases same 111 * 0x80-0x870 primary TSS (CPU 0..254) same 112 * 0x878-0x1068 percpu area (CPU 0..254) not used 113 * 114 * Note that the same segment can be used for 32-bit and 64-bit data segments 115 * (the L bit is only defined for code segments) 116 * 117 * Selectors 0x08-0x10 and 0x3b-0x4b are set up for use with the SYSCALL 118 * and SYSRET instructions. 119 */ 120 121 #define KERNEL_CS 0x08 122 #define KERNEL_DS 0x10 123 #define NP_SEL 0x18 124 #ifdef __x86_64__ 125 #define KERNEL_CS32 0x20 126 #else 127 #define TSS_INTR 0x20 128 #endif 129 #define KERNEL_CS16 0x28 130 #define KERNEL_DS16 0x30 131 #define USER_CS32 0x3b 132 #define USER_DS 0x43 133 #ifdef __x86_64__ 134 #define USER_CS64 0x4b 135 #endif 136 137 /* Synonyms */ 138 #define KERNEL_DS32 KERNEL_DS 139 #define USER_DS32 USER_DS 140 141 #ifdef __x86_64__ 142 #define KERNEL_CS64 KERNEL_CS 143 #define USER_CS USER_CS64 144 #define KERNEL_DS64 KERNEL_DS 145 #define USER_DS64 USER_DS 146 #else 147 #define KERNEL_CS32 KERNEL_CS 148 #define USER_CS USER_CS32 149 #endif 150 151 #define FIRST_SPARE_SEL 0x50 152 #define TSS_MAIN 0x80 153 154 typedef struct { 155 unsigned short offset0; 156 unsigned short selector; 157 unsigned short ist : 3; 158 unsigned short : 5; 159 unsigned short type : 4; 160 unsigned short : 1; 161 unsigned short dpl : 2; 162 unsigned short p : 1; 163 unsigned short offset1; 164 #ifdef __x86_64__ 165 unsigned offset2; 166 unsigned reserved; 167 #endif 168 } idt_entry_t; 169 170 typedef struct { 171 uint16_t limit1; 172 uint16_t base1; 173 uint8_t base2; 174 union { 175 uint16_t type_limit_flags; /* Type and limit flags */ 176 struct { 177 uint16_t type:4; 178 uint16_t s:1; 179 uint16_t dpl:2; 180 uint16_t p:1; 181 uint16_t limit2:4; 182 uint16_t avl:1; 183 uint16_t l:1; 184 uint16_t db:1; 185 uint16_t g:1; 186 } __attribute__((__packed__)); 187 } __attribute__((__packed__)); 188 uint8_t base3; 189 } __attribute__((__packed__)) gdt_entry_t; 190 191 #ifdef __x86_64__ 192 struct system_desc64 { 193 gdt_entry_t common; 194 uint32_t base4; 195 uint32_t zero; 196 } __attribute__((__packed__)); 197 #endif 198 199 #define DESC_BUSY 2 200 201 extern idt_entry_t boot_idt[256]; 202 203 #ifndef __x86_64__ 204 extern tss32_t tss[]; 205 extern tss32_t tss_intr; 206 void set_gdt_task_gate(u16 tss_sel, u16 sel); 207 void set_idt_task_gate(int vec, u16 sel); 208 void set_intr_task_gate(int vec, void *fn); 209 void setup_tss32(void); 210 #else 211 extern tss64_t tss[]; 212 #endif 213 extern gdt_entry_t gdt[]; 214 215 unsigned exception_vector(void); 216 int write_cr4_checking(unsigned long val); 217 unsigned exception_error_code(void); 218 bool exception_rflags_rf(void); 219 void set_idt_entry(int vec, void *addr, int dpl); 220 void set_idt_sel(int vec, u16 sel); 221 void set_idt_dpl(int vec, u16 dpl); 222 void set_gdt_entry(int sel, unsigned long base, u32 limit, u8 access, u8 gran); 223 void set_intr_alt_stack(int e, void *fn); 224 void print_current_tss_info(void); 225 handler handle_exception(u8 v, handler fn); 226 void unhandled_exception(struct ex_regs *regs, bool cpu); 227 const char* exception_mnemonic(int vector); 228 229 bool test_for_exception(unsigned int ex, void (*trigger_func)(void *data), 230 void *data); 231 void __set_exception_jmpbuf(jmp_buf *addr); 232 #define set_exception_jmpbuf(jmpbuf) \ 233 (setjmp(jmpbuf) ? : (__set_exception_jmpbuf(&(jmpbuf)), 0)) 234 235 static inline void *get_idt_addr(idt_entry_t *entry) 236 { 237 uintptr_t addr = entry->offset0 | ((u32)entry->offset1 << 16); 238 #ifdef __x86_64__ 239 addr |= (u64)entry->offset2 << 32; 240 #endif 241 return (void *)addr; 242 } 243 244 extern gdt_entry_t *get_tss_descr(void); 245 extern unsigned long get_gdt_entry_base(gdt_entry_t *entry); 246 extern unsigned long get_gdt_entry_limit(gdt_entry_t *entry); 247 248 #endif 249