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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 | /* Written 2000 by Andi Kleen */ #ifndef __ARCH_DESC_H #define __ARCH_DESC_H #include <linux/threads.h> #include <asm/ldt.h> #ifndef __ASSEMBLY__ #include <linux/string.h> #include <asm/segment.h> #include <asm/mmu.h> // 8 byte segment descriptor struct desc_struct { u16 limit0; u16 base0; unsigned base1 : 8, type : 4, s : 1, dpl : 2, p : 1; unsigned limit : 4, avl : 1, l : 1, d : 1, g : 1, base2 : 8; } __attribute__((packed)); struct n_desc_struct { unsigned int a,b; }; extern struct desc_struct cpu_gdt_table[NR_CPUS][GDT_ENTRIES]; enum { GATE_INTERRUPT = 0xE, GATE_TRAP = 0xF, GATE_CALL = 0xC, }; // 16byte gate struct gate_struct { u16 offset_low; u16 segment; unsigned ist : 3, zero0 : 5, type : 5, dpl : 2, p : 1; u16 offset_middle; u32 offset_high; u32 zero1; } __attribute__((packed)); #define PTR_LOW(x) ((unsigned long)(x) & 0xFFFF) #define PTR_MIDDLE(x) (((unsigned long)(x) >> 16) & 0xFFFF) #define PTR_HIGH(x) ((unsigned long)(x) >> 32) enum { DESC_TSS = 0x9, DESC_LDT = 0x2, }; // LDT or TSS descriptor in the GDT. 16 bytes. struct ldttss_desc { u16 limit0; u16 base0; unsigned base1 : 8, type : 5, dpl : 2, p : 1; unsigned limit1 : 4, zero0 : 3, g : 1, base2 : 8; u32 base3; u32 zero1; } __attribute__((packed)); struct desc_ptr { unsigned short size; unsigned long address; } __attribute__((packed)) ; #define load_TR_desc() asm volatile("ltr %w0"::"r" (GDT_ENTRY_TSS*8)) #define load_LDT_desc() asm volatile("lldt %w0"::"r" (GDT_ENTRY_LDT*8)) #define clear_LDT() asm volatile("lldt %w0"::"r" (0)) /* * This is the ldt that every process will get unless we need * something other than this. */ extern struct desc_struct default_ldt[]; extern struct gate_struct idt_table[]; static inline void _set_gate(void *adr, unsigned type, unsigned long func, unsigned dpl, unsigned ist) { struct gate_struct s; s.offset_low = PTR_LOW(func); s.segment = __KERNEL_CS; s.ist = ist; s.p = 1; s.dpl = dpl; s.zero0 = 0; s.zero1 = 0; s.type = type; s.offset_middle = PTR_MIDDLE(func); s.offset_high = PTR_HIGH(func); /* does not need to be atomic because it is only done once at setup time */ memcpy(adr, &s, 16); } static inline void set_intr_gate(int nr, void *func) { _set_gate(&idt_table[nr], GATE_INTERRUPT, (unsigned long) func, 0, 0); } static inline void set_intr_gate_ist(int nr, void *func, unsigned ist) { _set_gate(&idt_table[nr], GATE_INTERRUPT, (unsigned long) func, 0, ist); } static inline void set_system_gate(int nr, void *func) { _set_gate(&idt_table[nr], GATE_INTERRUPT, (unsigned long) func, 3, 0); } static inline void set_tssldt_descriptor(void *ptr, unsigned long tss, unsigned type, unsigned size) { struct ldttss_desc d; memset(&d,0,sizeof(d)); d.limit0 = size & 0xFFFF; d.base0 = PTR_LOW(tss); d.base1 = PTR_MIDDLE(tss) & 0xFF; d.type = type; d.p = 1; d.limit1 = (size >> 16) & 0xF; d.base2 = (PTR_MIDDLE(tss) >> 8) & 0xFF; d.base3 = PTR_HIGH(tss); memcpy(ptr, &d, 16); } static inline void set_tss_desc(unsigned cpu, void *addr) { set_tssldt_descriptor(&cpu_gdt_table[cpu][GDT_ENTRY_TSS], (unsigned long)addr, DESC_TSS, sizeof(struct tss_struct) - 1); } static inline void set_ldt_desc(unsigned cpu, void *addr, int size) { set_tssldt_descriptor(&cpu_gdt_table[cpu][GDT_ENTRY_LDT], (unsigned long)addr, DESC_LDT, size * 8 - 1); } static inline void set_seg_base(unsigned cpu, int entry, void *base) { struct desc_struct *d = &cpu_gdt_table[cpu][entry]; u32 addr = (u32)(u64)base; BUG_ON((u64)base >> 32); d->base0 = addr & 0xffff; d->base1 = (addr >> 16) & 0xff; d->base2 = (addr >> 24) & 0xff; } #define LDT_entry_a(info) \ ((((info)->base_addr & 0x0000ffff) << 16) | ((info)->limit & 0x0ffff)) /* Don't allow setting of the lm bit. It is useless anyways because 64bit system calls require __USER_CS. */ #define LDT_entry_b(info) \ (((info)->base_addr & 0xff000000) | \ (((info)->base_addr & 0x00ff0000) >> 16) | \ ((info)->limit & 0xf0000) | \ (((info)->read_exec_only ^ 1) << 9) | \ ((info)->contents << 10) | \ (((info)->seg_not_present ^ 1) << 15) | \ ((info)->seg_32bit << 22) | \ ((info)->limit_in_pages << 23) | \ ((info)->useable << 20) | \ /* ((info)->lm << 21) | */ \ 0x7000) #define LDT_empty(info) (\ (info)->base_addr == 0 && \ (info)->limit == 0 && \ (info)->contents == 0 && \ (info)->read_exec_only == 1 && \ (info)->seg_32bit == 0 && \ (info)->limit_in_pages == 0 && \ (info)->seg_not_present == 1 && \ (info)->useable == 0 && \ (info)->lm == 0) #if TLS_SIZE != 24 # error update this code. #endif static inline void load_TLS(struct thread_struct *t, unsigned int cpu) { u64 *gdt = (u64 *)(cpu_gdt_table[cpu] + GDT_ENTRY_TLS_MIN); gdt[0] = t->tls_array[0]; gdt[1] = t->tls_array[1]; gdt[2] = t->tls_array[2]; } /* * load one particular LDT into the current CPU */ extern inline void load_LDT_nolock (mm_context_t *pc, int cpu) { int count = pc->size; if (likely(!count)) { clear_LDT(); return; } set_ldt_desc(cpu, pc->ldt, count); load_LDT_desc(); } static inline void load_LDT(mm_context_t *pc) { int cpu = get_cpu(); load_LDT_nolock(pc, cpu); put_cpu(); } extern struct desc_ptr idt_descr; #endif /* !__ASSEMBLY__ */ #endif |