1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/*-
* Copyright (c) 2012 NetApp, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _VMM_INSTRUCTION_EMUL_H_
#define _VMM_INSTRUCTION_EMUL_H_
/*
* The data structures 'vie' and 'vie_op' are meant to be opaque to the
* consumers of instruction decoding. The only reason why their contents
* need to be exposed is because they are part of the 'vm_exit' structure.
*/
struct vie_op {
uint8_t op_byte; /* actual opcode byte */
uint8_t op_type; /* type of operation (e.g. MOV) */
uint16_t op_flags;
};
#define VIE_INST_SIZE 15
struct vie {
uint8_t inst[VIE_INST_SIZE]; /* instruction bytes */
uint8_t num_valid; /* size of the instruction */
uint8_t num_processed;
uint8_t rex_w:1, /* REX prefix */
rex_r:1,
rex_x:1,
rex_b:1,
rex_present:1;
uint8_t mod:2, /* ModRM byte */
reg:4,
rm:4;
uint8_t ss:2, /* SIB byte */
index:4,
base:4;
uint8_t disp_bytes;
uint8_t imm_bytes;
uint8_t scale;
int base_register; /* VM_REG_GUEST_xyz */
int index_register; /* VM_REG_GUEST_xyz */
int64_t displacement; /* optional addr displacement */
int64_t immediate; /* optional immediate operand */
uint8_t decoded; /* set to 1 if successfully decoded */
struct vie_op op; /* opcode description */
};
/*
* Callback functions to read and write memory regions.
*/
typedef int (*mem_region_read_t)(void *vm, int cpuid, uint64_t gpa,
uint64_t *rval, int rsize, void *arg);
typedef int (*mem_region_write_t)(void *vm, int cpuid, uint64_t gpa,
uint64_t wval, int wsize, void *arg);
/*
* Emulate the decoded 'vie' instruction.
*
* The callbacks 'mrr' and 'mrw' emulate reads and writes to the memory region
* containing 'gpa'. 'mrarg' is an opaque argument that is passed into the
* callback functions.
*
* 'void *vm' should be 'struct vm *' when called from kernel context and
* 'struct vmctx *' when called from user context.
* s
*/
int vmm_emulate_instruction(void *vm, int cpuid, uint64_t gpa, struct vie *vie,
mem_region_read_t mrr, mem_region_write_t mrw,
void *mrarg);
#ifdef _KERNEL
/*
* APIs to fetch and decode the instruction from nested page fault handler.
*/
int vmm_fetch_instruction(struct vm *vm, int cpuid,
uint64_t rip, int inst_length, uint64_t cr3,
struct vie *vie);
/*
* Decode the instruction fetched into 'vie' so it can be emulated.
*
* 'gla' is the guest linear address provided by the hardware assist
* that caused the nested page table fault. It is used to verify that
* the software instruction decoding is in agreement with the hardware.
*
* Some hardware assists do not provide the 'gla' to the hypervisor.
* To skip the 'gla' verification for this or any other reason pass
* in VIE_INVALID_GLA instead.
*/
#define VIE_INVALID_GLA (1UL << 63) /* a non-canonical address */
int vmm_decode_instruction(struct vm *vm, int cpuid,
uint64_t gla, struct vie *vie);
#endif /* _KERNEL */
#endif /* _VMM_INSTRUCTION_EMUL_H_ */
|
