x86_task.c (6429B)
1 // This software is licensed under the terms of the GNU General Public 2 // License version 2, as published by the Free Software Foundation, and 3 // may be copied, distributed, and modified under those terms. 4 // 5 // This program is distributed in the hope that it will be useful, 6 // but WITHOUT ANY WARRANTY; without even the implied warranty of 7 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 8 // GNU General Public License for more details. 9 #include "qemu/osdep.h" 10 #include "panic.h" 11 #include "qemu/error-report.h" 12 13 #include "sysemu/hvf.h" 14 #include "hvf-i386.h" 15 #include "vmcs.h" 16 #include "vmx.h" 17 #include "x86.h" 18 #include "x86_descr.h" 19 #include "x86_mmu.h" 20 #include "x86_decode.h" 21 #include "x86_emu.h" 22 #include "x86_task.h" 23 #include "x86hvf.h" 24 25 #include <Hypervisor/hv.h> 26 #include <Hypervisor/hv_vmx.h> 27 28 #include "hw/i386/apic_internal.h" 29 #include "qemu/main-loop.h" 30 #include "qemu/accel.h" 31 #include "target/i386/cpu.h" 32 33 // TODO: taskswitch handling 34 static void save_state_to_tss32(CPUState *cpu, struct x86_tss_segment32 *tss) 35 { 36 X86CPU *x86_cpu = X86_CPU(cpu); 37 CPUX86State *env = &x86_cpu->env; 38 39 /* CR3 and ldt selector are not saved intentionally */ 40 tss->eip = (uint32_t)env->eip; 41 tss->eflags = (uint32_t)env->eflags; 42 tss->eax = EAX(env); 43 tss->ecx = ECX(env); 44 tss->edx = EDX(env); 45 tss->ebx = EBX(env); 46 tss->esp = ESP(env); 47 tss->ebp = EBP(env); 48 tss->esi = ESI(env); 49 tss->edi = EDI(env); 50 51 tss->es = vmx_read_segment_selector(cpu, R_ES).sel; 52 tss->cs = vmx_read_segment_selector(cpu, R_CS).sel; 53 tss->ss = vmx_read_segment_selector(cpu, R_SS).sel; 54 tss->ds = vmx_read_segment_selector(cpu, R_DS).sel; 55 tss->fs = vmx_read_segment_selector(cpu, R_FS).sel; 56 tss->gs = vmx_read_segment_selector(cpu, R_GS).sel; 57 } 58 59 static void load_state_from_tss32(CPUState *cpu, struct x86_tss_segment32 *tss) 60 { 61 X86CPU *x86_cpu = X86_CPU(cpu); 62 CPUX86State *env = &x86_cpu->env; 63 64 wvmcs(cpu->hvf->fd, VMCS_GUEST_CR3, tss->cr3); 65 66 env->eip = tss->eip; 67 env->eflags = tss->eflags | 2; 68 69 /* General purpose registers */ 70 RAX(env) = tss->eax; 71 RCX(env) = tss->ecx; 72 RDX(env) = tss->edx; 73 RBX(env) = tss->ebx; 74 RSP(env) = tss->esp; 75 RBP(env) = tss->ebp; 76 RSI(env) = tss->esi; 77 RDI(env) = tss->edi; 78 79 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ldt}}, R_LDTR); 80 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->es}}, R_ES); 81 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->cs}}, R_CS); 82 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ss}}, R_SS); 83 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ds}}, R_DS); 84 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->fs}}, R_FS); 85 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->gs}}, R_GS); 86 } 87 88 static int task_switch_32(CPUState *cpu, x68_segment_selector tss_sel, x68_segment_selector old_tss_sel, 89 uint64_t old_tss_base, struct x86_segment_descriptor *new_desc) 90 { 91 struct x86_tss_segment32 tss_seg; 92 uint32_t new_tss_base = x86_segment_base(new_desc); 93 uint32_t eip_offset = offsetof(struct x86_tss_segment32, eip); 94 uint32_t ldt_sel_offset = offsetof(struct x86_tss_segment32, ldt); 95 96 vmx_read_mem(cpu, &tss_seg, old_tss_base, sizeof(tss_seg)); 97 save_state_to_tss32(cpu, &tss_seg); 98 99 vmx_write_mem(cpu, old_tss_base + eip_offset, &tss_seg.eip, ldt_sel_offset - eip_offset); 100 vmx_read_mem(cpu, &tss_seg, new_tss_base, sizeof(tss_seg)); 101 102 if (old_tss_sel.sel != 0xffff) { 103 tss_seg.prev_tss = old_tss_sel.sel; 104 105 vmx_write_mem(cpu, new_tss_base, &tss_seg.prev_tss, sizeof(tss_seg.prev_tss)); 106 } 107 load_state_from_tss32(cpu, &tss_seg); 108 return 0; 109 } 110 111 void vmx_handle_task_switch(CPUState *cpu, x68_segment_selector tss_sel, int reason, bool gate_valid, uint8_t gate, uint64_t gate_type) 112 { 113 uint64_t rip = rreg(cpu->hvf->fd, HV_X86_RIP); 114 if (!gate_valid || (gate_type != VMCS_INTR_T_HWEXCEPTION && 115 gate_type != VMCS_INTR_T_HWINTR && 116 gate_type != VMCS_INTR_T_NMI)) { 117 int ins_len = rvmcs(cpu->hvf->fd, VMCS_EXIT_INSTRUCTION_LENGTH); 118 macvm_set_rip(cpu, rip + ins_len); 119 return; 120 } 121 122 load_regs(cpu); 123 124 struct x86_segment_descriptor curr_tss_desc, next_tss_desc; 125 int ret; 126 x68_segment_selector old_tss_sel = vmx_read_segment_selector(cpu, R_TR); 127 uint64_t old_tss_base = vmx_read_segment_base(cpu, R_TR); 128 uint32_t desc_limit; 129 struct x86_call_gate task_gate_desc; 130 struct vmx_segment vmx_seg; 131 132 X86CPU *x86_cpu = X86_CPU(cpu); 133 CPUX86State *env = &x86_cpu->env; 134 135 x86_read_segment_descriptor(cpu, &next_tss_desc, tss_sel); 136 x86_read_segment_descriptor(cpu, &curr_tss_desc, old_tss_sel); 137 138 if (reason == TSR_IDT_GATE && gate_valid) { 139 int dpl; 140 141 ret = x86_read_call_gate(cpu, &task_gate_desc, gate); 142 143 dpl = task_gate_desc.dpl; 144 x68_segment_selector cs = vmx_read_segment_selector(cpu, R_CS); 145 if (tss_sel.rpl > dpl || cs.rpl > dpl) 146 ;//DPRINTF("emulate_gp"); 147 } 148 149 desc_limit = x86_segment_limit(&next_tss_desc); 150 if (!next_tss_desc.p || ((desc_limit < 0x67 && (next_tss_desc.type & 8)) || desc_limit < 0x2b)) { 151 VM_PANIC("emulate_ts"); 152 } 153 154 if (reason == TSR_IRET || reason == TSR_JMP) { 155 curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */ 156 x86_write_segment_descriptor(cpu, &curr_tss_desc, old_tss_sel); 157 } 158 159 if (reason == TSR_IRET) 160 env->eflags &= ~NT_MASK; 161 162 if (reason != TSR_CALL && reason != TSR_IDT_GATE) 163 old_tss_sel.sel = 0xffff; 164 165 if (reason != TSR_IRET) { 166 next_tss_desc.type |= (1 << 1); /* set busy flag */ 167 x86_write_segment_descriptor(cpu, &next_tss_desc, tss_sel); 168 } 169 170 if (next_tss_desc.type & 8) 171 ret = task_switch_32(cpu, tss_sel, old_tss_sel, old_tss_base, &next_tss_desc); 172 else 173 //ret = task_switch_16(cpu, tss_sel, old_tss_sel, old_tss_base, &next_tss_desc); 174 VM_PANIC("task_switch_16"); 175 176 macvm_set_cr0(cpu->hvf->fd, rvmcs(cpu->hvf->fd, VMCS_GUEST_CR0) | 177 CR0_TS_MASK); 178 x86_segment_descriptor_to_vmx(cpu, tss_sel, &next_tss_desc, &vmx_seg); 179 vmx_write_segment_descriptor(cpu, &vmx_seg, R_TR); 180 181 store_regs(cpu); 182 183 hv_vcpu_invalidate_tlb(cpu->hvf->fd); 184 }