x86_task.c (6450B)
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-common.h" 12#include "qemu/error-report.h" 13 14#include "sysemu/hvf.h" 15#include "hvf-i386.h" 16#include "vmcs.h" 17#include "vmx.h" 18#include "x86.h" 19#include "x86_descr.h" 20#include "x86_mmu.h" 21#include "x86_decode.h" 22#include "x86_emu.h" 23#include "x86_task.h" 24#include "x86hvf.h" 25 26#include <Hypervisor/hv.h> 27#include <Hypervisor/hv_vmx.h> 28 29#include "hw/i386/apic_internal.h" 30#include "qemu/main-loop.h" 31#include "qemu/accel.h" 32#include "target/i386/cpu.h" 33 34// TODO: taskswitch handling 35static void save_state_to_tss32(CPUState *cpu, struct x86_tss_segment32 *tss) 36{ 37 X86CPU *x86_cpu = X86_CPU(cpu); 38 CPUX86State *env = &x86_cpu->env; 39 40 /* CR3 and ldt selector are not saved intentionally */ 41 tss->eip = (uint32_t)env->eip; 42 tss->eflags = (uint32_t)env->eflags; 43 tss->eax = EAX(env); 44 tss->ecx = ECX(env); 45 tss->edx = EDX(env); 46 tss->ebx = EBX(env); 47 tss->esp = ESP(env); 48 tss->ebp = EBP(env); 49 tss->esi = ESI(env); 50 tss->edi = EDI(env); 51 52 tss->es = vmx_read_segment_selector(cpu, R_ES).sel; 53 tss->cs = vmx_read_segment_selector(cpu, R_CS).sel; 54 tss->ss = vmx_read_segment_selector(cpu, R_SS).sel; 55 tss->ds = vmx_read_segment_selector(cpu, R_DS).sel; 56 tss->fs = vmx_read_segment_selector(cpu, R_FS).sel; 57 tss->gs = vmx_read_segment_selector(cpu, R_GS).sel; 58} 59 60static void load_state_from_tss32(CPUState *cpu, struct x86_tss_segment32 *tss) 61{ 62 X86CPU *x86_cpu = X86_CPU(cpu); 63 CPUX86State *env = &x86_cpu->env; 64 65 wvmcs(cpu->hvf->fd, VMCS_GUEST_CR3, tss->cr3); 66 67 env->eip = tss->eip; 68 env->eflags = tss->eflags | 2; 69 70 /* General purpose registers */ 71 RAX(env) = tss->eax; 72 RCX(env) = tss->ecx; 73 RDX(env) = tss->edx; 74 RBX(env) = tss->ebx; 75 RSP(env) = tss->esp; 76 RBP(env) = tss->ebp; 77 RSI(env) = tss->esi; 78 RDI(env) = tss->edi; 79 80 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ldt}}, R_LDTR); 81 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->es}}, R_ES); 82 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->cs}}, R_CS); 83 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ss}}, R_SS); 84 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->ds}}, R_DS); 85 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->fs}}, R_FS); 86 vmx_write_segment_selector(cpu, (x68_segment_selector){{tss->gs}}, R_GS); 87} 88 89static int task_switch_32(CPUState *cpu, x68_segment_selector tss_sel, x68_segment_selector old_tss_sel, 90 uint64_t old_tss_base, struct x86_segment_descriptor *new_desc) 91{ 92 struct x86_tss_segment32 tss_seg; 93 uint32_t new_tss_base = x86_segment_base(new_desc); 94 uint32_t eip_offset = offsetof(struct x86_tss_segment32, eip); 95 uint32_t ldt_sel_offset = offsetof(struct x86_tss_segment32, ldt); 96 97 vmx_read_mem(cpu, &tss_seg, old_tss_base, sizeof(tss_seg)); 98 save_state_to_tss32(cpu, &tss_seg); 99 100 vmx_write_mem(cpu, old_tss_base + eip_offset, &tss_seg.eip, ldt_sel_offset - eip_offset); 101 vmx_read_mem(cpu, &tss_seg, new_tss_base, sizeof(tss_seg)); 102 103 if (old_tss_sel.sel != 0xffff) { 104 tss_seg.prev_tss = old_tss_sel.sel; 105 106 vmx_write_mem(cpu, new_tss_base, &tss_seg.prev_tss, sizeof(tss_seg.prev_tss)); 107 } 108 load_state_from_tss32(cpu, &tss_seg); 109 return 0; 110} 111 112void vmx_handle_task_switch(CPUState *cpu, x68_segment_selector tss_sel, int reason, bool gate_valid, uint8_t gate, uint64_t gate_type) 113{ 114 uint64_t rip = rreg(cpu->hvf->fd, HV_X86_RIP); 115 if (!gate_valid || (gate_type != VMCS_INTR_T_HWEXCEPTION && 116 gate_type != VMCS_INTR_T_HWINTR && 117 gate_type != VMCS_INTR_T_NMI)) { 118 int ins_len = rvmcs(cpu->hvf->fd, VMCS_EXIT_INSTRUCTION_LENGTH); 119 macvm_set_rip(cpu, rip + ins_len); 120 return; 121 } 122 123 load_regs(cpu); 124 125 struct x86_segment_descriptor curr_tss_desc, next_tss_desc; 126 int ret; 127 x68_segment_selector old_tss_sel = vmx_read_segment_selector(cpu, R_TR); 128 uint64_t old_tss_base = vmx_read_segment_base(cpu, R_TR); 129 uint32_t desc_limit; 130 struct x86_call_gate task_gate_desc; 131 struct vmx_segment vmx_seg; 132 133 X86CPU *x86_cpu = X86_CPU(cpu); 134 CPUX86State *env = &x86_cpu->env; 135 136 x86_read_segment_descriptor(cpu, &next_tss_desc, tss_sel); 137 x86_read_segment_descriptor(cpu, &curr_tss_desc, old_tss_sel); 138 139 if (reason == TSR_IDT_GATE && gate_valid) { 140 int dpl; 141 142 ret = x86_read_call_gate(cpu, &task_gate_desc, gate); 143 144 dpl = task_gate_desc.dpl; 145 x68_segment_selector cs = vmx_read_segment_selector(cpu, R_CS); 146 if (tss_sel.rpl > dpl || cs.rpl > dpl) 147 ;//DPRINTF("emulate_gp"); 148 } 149 150 desc_limit = x86_segment_limit(&next_tss_desc); 151 if (!next_tss_desc.p || ((desc_limit < 0x67 && (next_tss_desc.type & 8)) || desc_limit < 0x2b)) { 152 VM_PANIC("emulate_ts"); 153 } 154 155 if (reason == TSR_IRET || reason == TSR_JMP) { 156 curr_tss_desc.type &= ~(1 << 1); /* clear busy flag */ 157 x86_write_segment_descriptor(cpu, &curr_tss_desc, old_tss_sel); 158 } 159 160 if (reason == TSR_IRET) 161 env->eflags &= ~NT_MASK; 162 163 if (reason != TSR_CALL && reason != TSR_IDT_GATE) 164 old_tss_sel.sel = 0xffff; 165 166 if (reason != TSR_IRET) { 167 next_tss_desc.type |= (1 << 1); /* set busy flag */ 168 x86_write_segment_descriptor(cpu, &next_tss_desc, tss_sel); 169 } 170 171 if (next_tss_desc.type & 8) 172 ret = task_switch_32(cpu, tss_sel, old_tss_sel, old_tss_base, &next_tss_desc); 173 else 174 //ret = task_switch_16(cpu, tss_sel, old_tss_sel, old_tss_base, &next_tss_desc); 175 VM_PANIC("task_switch_16"); 176 177 macvm_set_cr0(cpu->hvf->fd, rvmcs(cpu->hvf->fd, VMCS_GUEST_CR0) | CR0_TS); 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 hv_vcpu_flush(cpu->hvf->fd); 185}