vmm_instruction_emul.h revision 245652 
1/*-
2 * Copyright (c) 2012 NetApp, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * 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: head/sys/amd64/include/vmm_instruction_emul.h 245652 2013-01-19 04:18:52Z neel $
27 */
28
29#ifndef	_VMM_INSTRUCTION_EMUL_H_
30#define	_VMM_INSTRUCTION_EMUL_H_
31
32/*
33 * The data structures 'vie' and 'vie_op' are meant to be opaque to the
34 * consumers of instruction decoding. The only reason why their contents
35 * need to be exposed is because they are part of the 'vm_exit' structure.
36 */
37struct vie_op {
38	uint8_t		op_byte;	/* actual opcode byte */
39	uint8_t		op_type;	/* type of operation (e.g. MOV) */
40	uint16_t	op_flags;
41};
42
43#define	VIE_INST_SIZE	15
44struct vie {
45	uint8_t		inst[VIE_INST_SIZE];	/* instruction bytes */
46	uint8_t		num_valid;		/* size of the instruction */
47	uint8_t		num_processed;
48
49	uint8_t		rex_w:1,		/* REX prefix */
50			rex_r:1,
51			rex_x:1,
52			rex_b:1;
53
54	uint8_t		mod:2,			/* ModRM byte */
55			reg:4,
56			rm:4;
57
58	uint8_t		ss:2,			/* SIB byte */
59			index:4,
60			base:4;
61
62	uint8_t		disp_bytes;
63	uint8_t		imm_bytes;
64
65	uint8_t		scale;
66	int		base_register;		/* VM_REG_GUEST_xyz */
67	int		index_register;		/* VM_REG_GUEST_xyz */
68
69	int64_t		displacement;		/* optional addr displacement */
70	int64_t		immediate;		/* optional immediate operand */
71
72	uint8_t		decoded;	/* set to 1 if successfully decoded */
73
74	struct vie_op	op;			/* opcode description */
75};
76
77/*
78 * Callback functions to read and write memory regions.
79 */
80typedef int (*mem_region_read_t)(void *vm, int cpuid, uint64_t gpa,
81				 uint64_t *rval, int rsize, void *arg);
82
83typedef int (*mem_region_write_t)(void *vm, int cpuid, uint64_t gpa,
84				  uint64_t wval, int wsize, void *arg);
85
86/*
87 * Emulate the decoded 'vie' instruction.
88 *
89 * The callbacks 'mrr' and 'mrw' emulate reads and writes to the memory region
90 * containing 'gpa'. 'mrarg' is an opaque argument that is passed into the
91 * callback functions.
92 *
93 * 'void *vm' should be 'struct vm *' when called from kernel context and
94 * 'struct vmctx *' when called from user context.
95 * s
96 */
97int vmm_emulate_instruction(void *vm, int cpuid, uint64_t gpa, struct vie *vie,
98			    mem_region_read_t mrr, mem_region_write_t mrw,
99			    void *mrarg);
100
101#ifdef _KERNEL
102/*
103 * APIs to fetch and decode the instruction from nested page fault handler.
104 */
105int vmm_fetch_instruction(struct vm *vm, int cpuid,
106			  uint64_t rip, int inst_length, uint64_t cr3,
107			  struct vie *vie);
108
109int vmm_decode_instruction(struct vm *vm, int cpuid,
110			   uint64_t gla, struct vie *vie);
111#endif	/* _KERNEL */
112
113#endif	/* _VMM_INSTRUCTION_EMUL_H_ */
114