arch_user_debugger.h revision 735f6748
1/*
2 * Copyright 2005-2011, Ingo Weinhold, ingo_weinhold@gmx.de.
3 * Distributed under the terms of the MIT License.
4 */
5#ifndef _KERNEL_ARCH_X86_USER_DEBUGGER_H
6#define _KERNEL_ARCH_X86_USER_DEBUGGER_H
7
8
9#define ARCH_INIT_USER_DEBUG x86_init_user_debug
10
11// number of breakpoints the CPU supports
12#define X86_BREAKPOINT_COUNT		4
13
14// debug status register DR6
15enum {
16	X86_DR6_B0			= 0,	// breakpoint condition detected
17	X86_DR6_B1			= 1,	//
18	X86_DR6_B2			= 2,	//
19	X86_DR6_B3			= 3,	//
20	X86_DR6_BD			= 13,	// debug register access detected
21	X86_DR6_BS			= 14,	// single step
22	X86_DR6_BT			= 15,	// task switch
23
24	X86_DR6_BREAKPOINT_MASK	= (1 << X86_DR6_B0) | (1 << X86_DR6_B1)
25								| (1 << X86_DR6_B2) | (1 << X86_DR6_B3),
26};
27
28// debug control register DR7 layout:
29// 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
30// LEN3  R/W3  LEN2  R/W2  LEN1  R/W1  LEN0  R/W0
31//
32// 15 14 13 12 11 10 9  8  7  6  5  4  3  2  1  0
33// 0  0  GD 0  0  1  GE LE G3 L3 G2 L2 G1 L1 G0 L0
34//
35enum {
36	X86_DR7_L0			= 0,	// local/global breakpoints enable
37	X86_DR7_G0			= 1,	//
38	X86_DR7_L1			= 2,	//
39	X86_DR7_G1			= 3,	//
40	X86_DR7_L2			= 4,	//
41	X86_DR7_G2			= 5,	//
42	X86_DR7_L3			= 6,	//
43	X86_DR7_G3			= 7,	//
44	X86_DR7_LE			= 8,	// local/global exact breakpoint
45	X86_DR7_GE			= 9,	//
46	X86_DR7_GD			= 13,	// general detect enable: disallows debug
47								// register access
48	X86_DR7_RW0_LSB		= 16,	// breakpoints type and len
49	X86_DR7_LEN0_LSB	= 18,	//
50	X86_DR7_RW1_LSB		= 20,	//
51	X86_DR7_LEN1_LSB	= 22,	//
52	X86_DR7_RW2_LSB		= 24,	//
53	X86_DR7_LEN2_LSB	= 26,	//
54	X86_DR7_RW3_LSB		= 28,	//
55	X86_DR7_LEN3_LSB	= 30,	//
56
57	X86_BREAKPOINTS_DISABLED_DR7
58		= (1 << 10) | (1 << X86_DR7_GE) | (1 << X86_DR7_LE),
59		// all breakpoints disabled
60};
61
62// the EFLAGS flags we need
63enum {
64	X86_EFLAGS_CF	= 0,		// carry flag
65	X86_EFLAGS_PF	= 2,		// parity flag
66	X86_EFLAGS_AF	= 4,		// auxiliary carry flag (adjust flag)
67	X86_EFLAGS_ZF	= 6,		// zero flag
68	X86_EFLAGS_SF	= 7,		// sign flag
69	X86_EFLAGS_TF	= 8,		// trap flag (single stepping)
70	X86_EFLAGS_DF	= 10,		// direction flag
71	X86_EFLAGS_OF	= 11,		// overflow flag
72	X86_EFLAGS_RF	= 16,		// resume flag (skips instruction breakpoint)
73
74	X86_EFLAGS_USER_SETTABLE_FLAGS
75		= (1 << X86_EFLAGS_CF) | (1 << X86_EFLAGS_PF) | (1 << X86_EFLAGS_AF)
76			| (1 << X86_EFLAGS_ZF) | (1 << X86_EFLAGS_SF) | (1 << X86_EFLAGS_DF)
77			| (1 << X86_EFLAGS_OF),
78};
79
80// x86 breakpoint types
81enum {
82	X86_INSTRUCTION_BREAKPOINT		= 0x0,
83	X86_DATA_WRITE_BREAKPOINT		= 0x1,
84	X86_IO_READ_WRITE_BREAKPOINT	= 0x2,		// >= 586
85	X86_DATA_READ_WRITE_BREAKPOINT	= 0x3,
86};
87
88// x86 breakpoint lengths
89enum {
90	X86_BREAKPOINT_LENGTH_1	= 0x0,
91	X86_BREAKPOINT_LENGTH_2	= 0x1,
92	X86_BREAKPOINT_LENGTH_4	= 0x3,
93};
94
95struct arch_breakpoint {
96	void	*address;	// NULL, if deactivated
97	size_t	type;		// one of the architecture types above
98	size_t	length;		// one of the length values above
99};
100
101struct arch_team_debug_info {
102	struct arch_breakpoint	breakpoints[X86_BREAKPOINT_COUNT];
103
104	size_t					dr7;	// debug control register DR7
105};
106
107struct arch_thread_debug_info {
108	uint32	flags;
109};
110
111// The software breakpoint instruction (int3).
112extern const uint8 kX86SoftwareBreakpoint[1];
113
114#ifdef __cplusplus
115extern "C" {
116#endif
117
118struct iframe;
119
120extern void x86_init_user_debug_at_kernel_exit(struct iframe *frame);
121extern void x86_exit_user_debug_at_kernel_entry();
122
123extern void x86_handle_debug_exception(struct iframe *frame);
124extern void x86_handle_breakpoint_exception(struct iframe *frame);
125
126extern void x86_init_user_debug();
127
128#ifdef __cplusplus
129}
130#endif
131
132// Feature macros we're supposed to define.
133#define DEBUG_MAX_BREAKPOINTS				X86_BREAKPOINT_COUNT
134#define DEBUG_MAX_WATCHPOINTS				X86_BREAKPOINT_COUNT
135#define DEBUG_SOFTWARE_BREAKPOINT			kX86SoftwareBreakpoint
136#define DEBUG_SOFTWARE_BREAKPOINT_SIZE		1
137#define DEBUG_SHARED_BREAK_AND_WATCHPOINTS	1
138
139
140#endif	// _KERNEL_ARCH_X86_USER_DEBUGGER_H
141