1 /* 2 * Copyright (C) 2016 Veertu Inc, 3 * Copyright (C) 2017 Google Inc, 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Lesser General Public 7 * License as published by the Free Software Foundation; either 8 * version 2.1 of the License, or (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public 16 * License along with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "qemu/osdep.h" 20 21 #include "cpu.h" 22 #include "qemu-common.h" 23 #include "x86_decode.h" 24 #include "x86_emu.h" 25 #include "vmcs.h" 26 #include "vmx.h" 27 #include "x86_mmu.h" 28 #include "x86_descr.h" 29 30 /* static uint32_t x86_segment_access_rights(struct x86_segment_descriptor *var) 31 { 32 uint32_t ar; 33 34 if (!var->p) { 35 ar = 1 << 16; 36 return ar; 37 } 38 39 ar = var->type & 15; 40 ar |= (var->s & 1) << 4; 41 ar |= (var->dpl & 3) << 5; 42 ar |= (var->p & 1) << 7; 43 ar |= (var->avl & 1) << 12; 44 ar |= (var->l & 1) << 13; 45 ar |= (var->db & 1) << 14; 46 ar |= (var->g & 1) << 15; 47 return ar; 48 }*/ 49 50 bool x86_read_segment_descriptor(struct CPUState *cpu, 51 struct x86_segment_descriptor *desc, 52 x68_segment_selector sel) 53 { 54 target_ulong base; 55 uint32_t limit; 56 57 memset(desc, 0, sizeof(*desc)); 58 59 /* valid gdt descriptors start from index 1 */ 60 if (!sel.index && GDT_SEL == sel.ti) { 61 return false; 62 } 63 64 if (GDT_SEL == sel.ti) { 65 base = rvmcs(cpu->hvf->fd, VMCS_GUEST_GDTR_BASE); 66 limit = rvmcs(cpu->hvf->fd, VMCS_GUEST_GDTR_LIMIT); 67 } else { 68 base = rvmcs(cpu->hvf->fd, VMCS_GUEST_LDTR_BASE); 69 limit = rvmcs(cpu->hvf->fd, VMCS_GUEST_LDTR_LIMIT); 70 } 71 72 if (sel.index * 8 >= limit) { 73 return false; 74 } 75 76 vmx_read_mem(cpu, desc, base + sel.index * 8, sizeof(*desc)); 77 return true; 78 } 79 80 bool x86_write_segment_descriptor(struct CPUState *cpu, 81 struct x86_segment_descriptor *desc, 82 x68_segment_selector sel) 83 { 84 target_ulong base; 85 uint32_t limit; 86 87 if (GDT_SEL == sel.ti) { 88 base = rvmcs(cpu->hvf->fd, VMCS_GUEST_GDTR_BASE); 89 limit = rvmcs(cpu->hvf->fd, VMCS_GUEST_GDTR_LIMIT); 90 } else { 91 base = rvmcs(cpu->hvf->fd, VMCS_GUEST_LDTR_BASE); 92 limit = rvmcs(cpu->hvf->fd, VMCS_GUEST_LDTR_LIMIT); 93 } 94 95 if (sel.index * 8 >= limit) { 96 printf("%s: gdt limit\n", __func__); 97 return false; 98 } 99 vmx_write_mem(cpu, base + sel.index * 8, desc, sizeof(*desc)); 100 return true; 101 } 102 103 bool x86_read_call_gate(struct CPUState *cpu, struct x86_call_gate *idt_desc, 104 int gate) 105 { 106 target_ulong base = rvmcs(cpu->hvf->fd, VMCS_GUEST_IDTR_BASE); 107 uint32_t limit = rvmcs(cpu->hvf->fd, VMCS_GUEST_IDTR_LIMIT); 108 109 memset(idt_desc, 0, sizeof(*idt_desc)); 110 if (gate * 8 >= limit) { 111 printf("%s: idt limit\n", __func__); 112 return false; 113 } 114 115 vmx_read_mem(cpu, idt_desc, base + gate * 8, sizeof(*idt_desc)); 116 return true; 117 } 118 119 bool x86_is_protected(struct CPUState *cpu) 120 { 121 uint64_t cr0 = rvmcs(cpu->hvf->fd, VMCS_GUEST_CR0); 122 return cr0 & CR0_PE; 123 } 124 125 bool x86_is_real(struct CPUState *cpu) 126 { 127 return !x86_is_protected(cpu); 128 } 129 130 bool x86_is_v8086(struct CPUState *cpu) 131 { 132 X86CPU *x86_cpu = X86_CPU(cpu); 133 CPUX86State *env = &x86_cpu->env; 134 return x86_is_protected(cpu) && (env->eflags & VM_MASK); 135 } 136 137 bool x86_is_long_mode(struct CPUState *cpu) 138 { 139 return rvmcs(cpu->hvf->fd, VMCS_GUEST_IA32_EFER) & MSR_EFER_LMA; 140 } 141 142 bool x86_is_long64_mode(struct CPUState *cpu) 143 { 144 struct vmx_segment desc; 145 vmx_read_segment_descriptor(cpu, &desc, R_CS); 146 147 return x86_is_long_mode(cpu) && ((desc.ar >> 13) & 1); 148 } 149 150 bool x86_is_paging_mode(struct CPUState *cpu) 151 { 152 uint64_t cr0 = rvmcs(cpu->hvf->fd, VMCS_GUEST_CR0); 153 return cr0 & CR0_PG; 154 } 155 156 bool x86_is_pae_enabled(struct CPUState *cpu) 157 { 158 uint64_t cr4 = rvmcs(cpu->hvf->fd, VMCS_GUEST_CR4); 159 return cr4 & CR4_PAE; 160 } 161 162 target_ulong linear_addr(struct CPUState *cpu, target_ulong addr, X86Seg seg) 163 { 164 return vmx_read_segment_base(cpu, seg) + addr; 165 } 166 167 target_ulong linear_addr_size(struct CPUState *cpu, target_ulong addr, int size, 168 X86Seg seg) 169 { 170 switch (size) { 171 case 2: 172 addr = (uint16_t)addr; 173 break; 174 case 4: 175 addr = (uint32_t)addr; 176 break; 177 default: 178 break; 179 } 180 return linear_addr(cpu, addr, seg); 181 } 182 183 target_ulong linear_rip(struct CPUState *cpu, target_ulong rip) 184 { 185 return linear_addr(cpu, rip, R_CS); 186 } 187