xref: /haiku/headers/private/kernel/arch/x86/arch_user_debugger.h (revision 2b76973fa2401f7a5edf68e6470f3d3210cbcff3)
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 // On 32-bit, DR3 is used to hold the Thread*.
13 #ifdef __x86_64__
14 #	define X86_BREAKPOINT_COUNT		4
15 #else
16 #	define X86_BREAKPOINT_COUNT		3
17 #endif
18 
19 // debug status register DR6
20 enum {
21 	X86_DR6_B0			= 0,	// breakpoint condition detected
22 	X86_DR6_B1			= 1,	//
23 	X86_DR6_B2			= 2,	//
24 	X86_DR6_B3			= 3,	//
25 	X86_DR6_BD			= 13,	// debug register access detected
26 	X86_DR6_BS			= 14,	// single step
27 	X86_DR6_BT			= 15,	// task switch
28 
29 	X86_DR6_BREAKPOINT_MASK	= (1 << X86_DR6_B0) | (1 << X86_DR6_B1)
30 								| (1 << X86_DR6_B2) | (1 << X86_DR6_B3),
31 };
32 
33 // debug control register DR7 layout:
34 // 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
35 // LEN3  R/W3  LEN2  R/W2  LEN1  R/W1  LEN0  R/W0
36 //
37 // 15 14 13 12 11 10 9  8  7  6  5  4  3  2  1  0
38 // 0  0  GD 0  0  1  GE LE G3 L3 G2 L2 G1 L1 G0 L0
39 //
40 enum {
41 	X86_DR7_L0			= 0,	// local/global breakpoints enable
42 	X86_DR7_G0			= 1,	//
43 	X86_DR7_L1			= 2,	//
44 	X86_DR7_G1			= 3,	//
45 	X86_DR7_L2			= 4,	//
46 	X86_DR7_G2			= 5,	//
47 	X86_DR7_L3			= 6,	//
48 	X86_DR7_G3			= 7,	//
49 	X86_DR7_LE			= 8,	// local/global exact breakpoint
50 	X86_DR7_GE			= 9,	//
51 	X86_DR7_GD			= 13,	// general detect enable: disallows debug
52 								// register access
53 	X86_DR7_RW0_LSB		= 16,	// breakpoints type and len
54 	X86_DR7_LEN0_LSB	= 18,	//
55 	X86_DR7_RW1_LSB		= 20,	//
56 	X86_DR7_LEN1_LSB	= 22,	//
57 	X86_DR7_RW2_LSB		= 24,	//
58 	X86_DR7_LEN2_LSB	= 26,	//
59 	X86_DR7_RW3_LSB		= 28,	//
60 	X86_DR7_LEN3_LSB	= 30,	//
61 
62 	X86_BREAKPOINTS_DISABLED_DR7
63 		= (1 << 10) | (1 << X86_DR7_GE) | (1 << X86_DR7_LE),
64 		// all breakpoints disabled
65 };
66 
67 // the EFLAGS flags we need
68 enum {
69 	X86_EFLAGS_CF	= 0,		// carry flag
70 	X86_EFLAGS_PF	= 2,		// parity flag
71 	X86_EFLAGS_AF	= 4,		// auxiliary carry flag (adjust flag)
72 	X86_EFLAGS_ZF	= 6,		// zero flag
73 	X86_EFLAGS_SF	= 7,		// sign flag
74 	X86_EFLAGS_TF	= 8,		// trap flag (single stepping)
75 	X86_EFLAGS_DF	= 10,		// direction flag
76 	X86_EFLAGS_OF	= 11,		// overflow flag
77 	X86_EFLAGS_RF	= 16,		// resume flag (skips instruction breakpoint)
78 
79 	X86_EFLAGS_USER_SETTABLE_FLAGS
80 		= (1 << X86_EFLAGS_CF) | (1 << X86_EFLAGS_PF) | (1 << X86_EFLAGS_AF)
81 			| (1 << X86_EFLAGS_ZF) | (1 << X86_EFLAGS_SF) | (1 << X86_EFLAGS_DF)
82 			| (1 << X86_EFLAGS_OF),
83 };
84 
85 // x86 breakpoint types
86 enum {
87 	X86_INSTRUCTION_BREAKPOINT		= 0x0,
88 	X86_DATA_WRITE_BREAKPOINT		= 0x1,
89 	X86_IO_READ_WRITE_BREAKPOINT	= 0x2,		// >= 586
90 	X86_DATA_READ_WRITE_BREAKPOINT	= 0x3,
91 };
92 
93 // x86 breakpoint lengths
94 enum {
95 	X86_BREAKPOINT_LENGTH_1	= 0x0,
96 	X86_BREAKPOINT_LENGTH_2	= 0x1,
97 	X86_BREAKPOINT_LENGTH_4	= 0x3,
98 };
99 
100 struct arch_breakpoint {
101 	void	*address;	// NULL, if deactivated
102 	size_t	type;		// one of the architecture types above
103 	size_t	length;		// one of the length values above
104 };
105 
106 struct arch_team_debug_info {
107 	struct arch_breakpoint	breakpoints[X86_BREAKPOINT_COUNT];
108 
109 	size_t					dr7;	// debug control register DR7
110 };
111 
112 struct arch_thread_debug_info {
113 	uint32	flags;
114 };
115 
116 // The software breakpoint instruction (int3).
117 extern const uint8 kX86SoftwareBreakpoint[1];
118 
119 #ifdef __cplusplus
120 extern "C" {
121 #endif
122 
123 struct iframe;
124 
125 extern void x86_init_user_debug_at_kernel_exit(struct iframe *frame);
126 extern void x86_exit_user_debug_at_kernel_entry();
127 
128 extern void x86_handle_debug_exception(struct iframe *frame);
129 extern void x86_handle_breakpoint_exception(struct iframe *frame);
130 
131 extern void x86_init_user_debug();
132 
133 #ifdef __cplusplus
134 }
135 #endif
136 
137 // Feature macros we're supposed to define.
138 #define DEBUG_MAX_BREAKPOINTS				X86_BREAKPOINT_COUNT
139 #define DEBUG_MAX_WATCHPOINTS				X86_BREAKPOINT_COUNT
140 #define DEBUG_SOFTWARE_BREAKPOINT			kX86SoftwareBreakpoint
141 #define DEBUG_SOFTWARE_BREAKPOINT_SIZE		1
142 #define DEBUG_SHARED_BREAK_AND_WATCHPOINTS	1
143 
144 
145 #endif	// _KERNEL_ARCH_X86_USER_DEBUGGER_H
146