2 * Copyright (c) 2011 NetApp, Inc.
3 * Copyright (c) 2013 Neel Natu <neel@freebsd.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <machine/asmacros.h>
32 #include "vmx_assym.h"
40 /* Be friendly to DTrace FBT's prologue/epilogue pattern matching */
41 #define VENTER push %rbp ; mov %rsp,%rbp
42 #define VLEAVE pop %rbp
45 * Save the guest context.
47 #define VMX_GUEST_SAVE \
48 movq %rdi,VMXCTX_GUEST_RDI(%rsp); \
49 movq %rsi,VMXCTX_GUEST_RSI(%rsp); \
50 movq %rdx,VMXCTX_GUEST_RDX(%rsp); \
51 movq %rcx,VMXCTX_GUEST_RCX(%rsp); \
52 movq %r8,VMXCTX_GUEST_R8(%rsp); \
53 movq %r9,VMXCTX_GUEST_R9(%rsp); \
54 movq %rax,VMXCTX_GUEST_RAX(%rsp); \
55 movq %rbx,VMXCTX_GUEST_RBX(%rsp); \
56 movq %rbp,VMXCTX_GUEST_RBP(%rsp); \
57 movq %r10,VMXCTX_GUEST_R10(%rsp); \
58 movq %r11,VMXCTX_GUEST_R11(%rsp); \
59 movq %r12,VMXCTX_GUEST_R12(%rsp); \
60 movq %r13,VMXCTX_GUEST_R13(%rsp); \
61 movq %r14,VMXCTX_GUEST_R14(%rsp); \
62 movq %r15,VMXCTX_GUEST_R15(%rsp); \
64 movq %rdi,VMXCTX_GUEST_CR2(%rsp); \
68 * Assumes that %rdi holds a pointer to the 'vmxctx'.
70 * On "return" all registers are updated to reflect guest state. The two
71 * exceptions are %rip and %rsp. These registers are atomically switched
72 * by hardware from the guest area of the vmcs.
74 * We modify %rsp to point to the 'vmxctx' so we can use it to restore
75 * host context in case of an error with 'vmlaunch' or 'vmresume'.
77 #define VMX_GUEST_RESTORE \
79 movq VMXCTX_GUEST_CR2(%rdi),%rsi; \
81 movq VMXCTX_GUEST_RSI(%rdi),%rsi; \
82 movq VMXCTX_GUEST_RDX(%rdi),%rdx; \
83 movq VMXCTX_GUEST_RCX(%rdi),%rcx; \
84 movq VMXCTX_GUEST_R8(%rdi),%r8; \
85 movq VMXCTX_GUEST_R9(%rdi),%r9; \
86 movq VMXCTX_GUEST_RAX(%rdi),%rax; \
87 movq VMXCTX_GUEST_RBX(%rdi),%rbx; \
88 movq VMXCTX_GUEST_RBP(%rdi),%rbp; \
89 movq VMXCTX_GUEST_R10(%rdi),%r10; \
90 movq VMXCTX_GUEST_R11(%rdi),%r11; \
91 movq VMXCTX_GUEST_R12(%rdi),%r12; \
92 movq VMXCTX_GUEST_R13(%rdi),%r13; \
93 movq VMXCTX_GUEST_R14(%rdi),%r14; \
94 movq VMXCTX_GUEST_R15(%rdi),%r15; \
95 movq VMXCTX_GUEST_RDI(%rdi),%rdi; /* restore rdi the last */
98 * Clobber the remaining registers with guest contents so they can't
101 #define VMX_GUEST_CLOBBER \
112 * Save and restore the host context.
114 * Assumes that %rdi holds a pointer to the 'vmxctx'.
116 #define VMX_HOST_SAVE \
117 movq %r15, VMXCTX_HOST_R15(%rdi); \
118 movq %r14, VMXCTX_HOST_R14(%rdi); \
119 movq %r13, VMXCTX_HOST_R13(%rdi); \
120 movq %r12, VMXCTX_HOST_R12(%rdi); \
121 movq %rbp, VMXCTX_HOST_RBP(%rdi); \
122 movq %rsp, VMXCTX_HOST_RSP(%rdi); \
123 movq %rbx, VMXCTX_HOST_RBX(%rdi); \
125 #define VMX_HOST_RESTORE \
126 movq VMXCTX_HOST_R15(%rdi), %r15; \
127 movq VMXCTX_HOST_R14(%rdi), %r14; \
128 movq VMXCTX_HOST_R13(%rdi), %r13; \
129 movq VMXCTX_HOST_R12(%rdi), %r12; \
130 movq VMXCTX_HOST_RBP(%rdi), %rbp; \
131 movq VMXCTX_HOST_RSP(%rdi), %rsp; \
132 movq VMXCTX_HOST_RBX(%rdi), %rbx; \
135 * vmx_enter_guest(struct vmxctx *vmxctx, int launched)
136 * %rdi: pointer to the 'vmxctx'
137 * %rsi: pointer to the 'vmx'
138 * %edx: launch state of the VMCS
139 * Interrupts must be disabled on entry.
141 ENTRY(vmx_enter_guest)
144 * Save host state before doing anything else.
149 * Activate guest pmap on this cpu.
151 movq VMXCTX_PMAP(%rdi), %r11
152 movl PCPU(CPUID), %eax
153 LK btsl %eax, PM_ACTIVE(%r11)
156 * If 'vmx->eptgen[curcpu]' is not identical to 'pmap->pm_eptgen'
157 * then we must invalidate all mappings associated with this EPTP.
159 movq PM_EPTGEN(%r11), %r10
160 cmpq %r10, VMX_EPTGEN(%rsi, %rax, 8)
163 /* Refresh 'vmx->eptgen[curcpu]' */
164 movq %r10, VMX_EPTGEN(%rsi, %rax, 8)
166 /* Setup the invept descriptor on the host stack */
168 movq VMX_EPTP(%rsi), %rax
171 mov $0x1, %eax /* Single context invalidate */
172 invept -16(%r11), %rax
173 jbe invept_error /* Check invept instruction error */
182 * In the common case 'vmresume' returns back to the host through
183 * 'vmx_exit_guest' with %rsp pointing to 'vmxctx'.
185 * If there is an error we return VMX_VMRESUME_ERROR to the caller.
187 movq %rsp, %rdi /* point %rdi back to 'vmxctx' */
188 movl $VMX_VMRESUME_ERROR, %eax
189 jmp decode_inst_error
195 * In the common case 'vmlaunch' returns back to the host through
196 * 'vmx_exit_guest' with %rsp pointing to 'vmxctx'.
198 * If there is an error we return VMX_VMLAUNCH_ERROR to the caller.
200 movq %rsp, %rdi /* point %rdi back to 'vmxctx' */
201 movl $VMX_VMLAUNCH_ERROR, %eax
202 jmp decode_inst_error
205 movl $VMX_INVEPT_ERROR, %eax
206 jmp decode_inst_error
209 movl $VM_FAIL_VALID, %r11d
211 movl $VM_FAIL_INVALID, %r11d
213 movl %r11d, VMXCTX_INST_FAIL_STATUS(%rdi)
216 * The return value is already populated in %eax so we cannot use
217 * it as a scratch register beyond this point.
221 * Deactivate guest pmap from this cpu.
223 movq VMXCTX_PMAP(%rdi), %r11
224 movl PCPU(CPUID), %r10d
225 LK btrl %r10d, PM_ACTIVE(%r11)
232 * Non-error VM-exit from the guest. Make this a label so it can
233 * be used by C code when setting up the VMCS.
234 * The VMCS-restored %rsp points to the struct vmxctx
237 .globl vmx_exit_guest_flush_rsb
238 vmx_exit_guest_flush_rsb:
240 * Save guest state that is not automatically saved in the vmcs.
245 * Deactivate guest pmap from this cpu.
247 movq VMXCTX_PMAP(%rdi), %r11
248 movl PCPU(CPUID), %r10d
249 LK btrl %r10d, PM_ACTIVE(%r11)
256 * To prevent malicious branch target predictions from
257 * affecting the host, overwrite all entries in the RSB upon
260 mov $16, %ecx /* 16 iterations, two calls per loop */
262 0: call 2f /* create an RSB entry. */
264 call 1b /* capture rogue speculation. */
265 2: call 2f /* create an RSB entry. */
267 call 1b /* capture rogue speculation. */
273 * This will return to the caller of 'vmx_enter_guest()' with a return
274 * value of VMX_GUEST_VMEXIT.
276 movl $VMX_GUEST_VMEXIT, %eax
280 .globl vmx_exit_guest
283 * Save guest state that is not automatically saved in the vmcs.
288 * Deactivate guest pmap from this cpu.
290 movq VMXCTX_PMAP(%rdi), %r11
291 movl PCPU(CPUID), %r10d
292 LK btrl %r10d, PM_ACTIVE(%r11)
299 * This will return to the caller of 'vmx_enter_guest()' with a return
300 * value of VMX_GUEST_VMEXIT.
302 movl $VMX_GUEST_VMEXIT, %eax
308 * %rdi = interrupt handler entry point
310 * Calling sequence described in the "Instruction Set Reference" for the "INT"
311 * instruction in Intel SDM, Vol 2.
315 mov %rsp, %r11 /* save %rsp */
316 and $~0xf, %rsp /* align on 16-byte boundary */
317 pushq $KERNEL_SS /* %ss */
318 pushq %r11 /* %rsp */
320 pushq $KERNEL_CS /* %cs */
321 cli /* disable interrupts */
322 callq *%rdi /* push %rip and call isr */