vmx_support.S revision 222112
1161748Scperciva/*- 2161748Scperciva * Copyright (c) 2011 NetApp, Inc. 3161748Scperciva * All rights reserved. 4161807Sru * 5161748Scperciva * Redistribution and use in source and binary forms, with or without 6161748Scperciva * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29#include <machine/asmacros.h> 30 31#include "vmx_assym.s" 32 33/* 34 * Assumes that %rdi holds a pointer to the 'vmxctx'. 35 * 36 * On "return" all registers are updated to reflect guest state. The two 37 * exceptions are %rip and %rsp. These registers are atomically switched 38 * by hardware from the guest area of the vmcs. 39 * 40 * We modify %rsp to point to the 'vmxctx' so we can use it to restore 41 * host context in case of an error with 'vmlaunch' or 'vmresume'. 42 */ 43#define VMX_GUEST_RESTORE \ 44 /* \ 45 * Disable interrupts before updating %rsp. The location that \ 46 * %rsp points to is a 'vmxctx' and not a real stack so we \ 47 * don't want an interrupt handler to trash it. \ 48 */ \ 49 cli; \ 50 movq %rdi,%rsp; \ 51 movq VMXCTX_GUEST_CR2(%rdi),%rsi; \ 52 movq %rsi,%cr2; \ 53 movq VMXCTX_GUEST_RSI(%rdi),%rsi; \ 54 movq VMXCTX_GUEST_RDX(%rdi),%rdx; \ 55 movq VMXCTX_GUEST_RCX(%rdi),%rcx; \ 56 movq VMXCTX_GUEST_R8(%rdi),%r8; \ 57 movq VMXCTX_GUEST_R9(%rdi),%r9; \ 58 movq VMXCTX_GUEST_RAX(%rdi),%rax; \ 59 movq VMXCTX_GUEST_RBX(%rdi),%rbx; \ 60 movq VMXCTX_GUEST_RBP(%rdi),%rbp; \ 61 movq VMXCTX_GUEST_R10(%rdi),%r10; \ 62 movq VMXCTX_GUEST_R11(%rdi),%r11; \ 63 movq VMXCTX_GUEST_R12(%rdi),%r12; \ 64 movq VMXCTX_GUEST_R13(%rdi),%r13; \ 65 movq VMXCTX_GUEST_R14(%rdi),%r14; \ 66 movq VMXCTX_GUEST_R15(%rdi),%r15; \ 67 movq VMXCTX_GUEST_RDI(%rdi),%rdi; /* restore rdi the last */ 68 69#define VM_INSTRUCTION_ERROR(reg) \ 70 jnc 1f; \ 71 movl $VM_FAIL_INVALID,reg; /* CF is set */ \ 72 jmp 3f; \ 731: jnz 2f; \ 74 movl $VM_FAIL_VALID,reg; /* ZF is set */ \ 75 jmp 3f; \ 762: movl $VM_SUCCESS,reg; \ 773: movl reg,VMXCTX_LAUNCH_ERROR(%rsp) 78 79 .text 80/* 81 * int vmx_setjmp(ctxp) 82 * %rdi = ctxp 83 * 84 * Return value is '0' when it returns directly from here. 85 * Return value is '1' when it returns after a vm exit through vmx_longjmp. 86 */ 87ENTRY(vmx_setjmp) 88 movq (%rsp),%rax /* return address */ 89 movq %r15,VMXCTX_HOST_R15(%rdi) 90 movq %r14,VMXCTX_HOST_R14(%rdi) 91 movq %r13,VMXCTX_HOST_R13(%rdi) 92 movq %r12,VMXCTX_HOST_R12(%rdi) 93 movq %rbp,VMXCTX_HOST_RBP(%rdi) 94 movq %rsp,VMXCTX_HOST_RSP(%rdi) 95 movq %rbx,VMXCTX_HOST_RBX(%rdi) 96 movq %rax,VMXCTX_HOST_RIP(%rdi) 97 98 /* 99 * XXX save host debug registers 100 */ 101 movl $VMX_RETURN_DIRECT,%eax 102 ret 103END(vmx_setjmp) 104 105/* 106 * void vmx_return(struct vmxctx *ctxp, int retval) 107 * %rdi = ctxp 108 * %rsi = retval 109 * Return to vmm context through vmx_setjmp() with a value of 'retval'. 110 */ 111ENTRY(vmx_return) 112 /* Restore host context. */ 113 movq VMXCTX_HOST_R15(%rdi),%r15 114 movq VMXCTX_HOST_R14(%rdi),%r14 115 movq VMXCTX_HOST_R13(%rdi),%r13 116 movq VMXCTX_HOST_R12(%rdi),%r12 117 movq VMXCTX_HOST_RBP(%rdi),%rbp 118 movq VMXCTX_HOST_RSP(%rdi),%rsp 119 movq VMXCTX_HOST_RBX(%rdi),%rbx 120 movq VMXCTX_HOST_RIP(%rdi),%rax 121 movq %rax,(%rsp) /* return address */ 122 123 /* 124 * XXX restore host debug registers 125 */ 126 movl %esi,%eax 127 ret 128END(vmx_return) 129 130/* 131 * void vmx_longjmp(void) 132 * %rsp points to the struct vmxctx 133 */ 134ENTRY(vmx_longjmp) 135 /* 136 * Save guest state that is not automatically saved in the vmcs. 137 */ 138 movq %rdi,VMXCTX_GUEST_RDI(%rsp) 139 movq %rsi,VMXCTX_GUEST_RSI(%rsp) 140 movq %rdx,VMXCTX_GUEST_RDX(%rsp) 141 movq %rcx,VMXCTX_GUEST_RCX(%rsp) 142 movq %r8,VMXCTX_GUEST_R8(%rsp) 143 movq %r9,VMXCTX_GUEST_R9(%rsp) 144 movq %rax,VMXCTX_GUEST_RAX(%rsp) 145 movq %rbx,VMXCTX_GUEST_RBX(%rsp) 146 movq %rbp,VMXCTX_GUEST_RBP(%rsp) 147 movq %r10,VMXCTX_GUEST_R10(%rsp) 148 movq %r11,VMXCTX_GUEST_R11(%rsp) 149 movq %r12,VMXCTX_GUEST_R12(%rsp) 150 movq %r13,VMXCTX_GUEST_R13(%rsp) 151 movq %r14,VMXCTX_GUEST_R14(%rsp) 152 movq %r15,VMXCTX_GUEST_R15(%rsp) 153 154 movq %cr2,%rdi 155 movq %rdi,VMXCTX_GUEST_CR2(%rsp) 156 157 movq %rsp,%rdi 158 movq $VMX_RETURN_LONGJMP,%rsi 159 160 addq $VMXCTX_TMPSTKTOP,%rsp 161 callq vmx_return 162END(vmx_longjmp) 163 164/* 165 * void vmx_resume(struct vmxctx *ctxp) 166 * %rdi = ctxp 167 * 168 * Although the return type is a 'void' this function may return indirectly 169 * through vmx_setjmp() with a return value of 2. 170 */ 171ENTRY(vmx_resume) 172 /* 173 * Restore guest state that is not automatically loaded from the vmcs. 174 */ 175 VMX_GUEST_RESTORE 176 177 vmresume 178 179 /* 180 * Capture the reason why vmresume failed. 181 */ 182 VM_INSTRUCTION_ERROR(%eax) 183 184 /* Return via vmx_setjmp with return value of VMX_RETURN_VMRESUME */ 185 movq %rsp,%rdi 186 movq $VMX_RETURN_VMRESUME,%rsi 187 188 addq $VMXCTX_TMPSTKTOP,%rsp 189 callq vmx_return 190END(vmx_resume) 191 192/* 193 * void vmx_launch(struct vmxctx *ctxp) 194 * %rdi = ctxp 195 * 196 * Although the return type is a 'void' this function may return indirectly 197 * through vmx_setjmp() with a return value of 3. 198 */ 199ENTRY(vmx_launch) 200 /* 201 * Restore guest state that is not automatically loaded from the vmcs. 202 */ 203 VMX_GUEST_RESTORE 204 205 vmlaunch 206 207 /* 208 * Capture the reason why vmlaunch failed. 209 */ 210 VM_INSTRUCTION_ERROR(%eax) 211 212 /* Return via vmx_setjmp with return value of VMX_RETURN_VMLAUNCH */ 213 movq %rsp,%rdi 214 movq $VMX_RETURN_VMLAUNCH,%rsi 215 216 addq $VMXCTX_TMPSTKTOP,%rsp 217 callq vmx_return 218END(vmx_launch) 219