dbregs.h revision 1.3 1 /* $NetBSD: dbregs.h,v 1.3 2017/01/18 05:12:00 kamil Exp $ */
2
3 /*-
4 * Copyright (c) 2016 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29
30 #ifndef _X86_DBREGS_H_
31 #define _X86_DBREGS_H_
32
33 #if defined(_KERNEL)
34
35 #include <sys/param.h>
36 #include <sys/types.h>
37
38 /*
39 * CPU Debug Status Register (DR6)
40 *
41 * Reserved bits: 4-12 and on x86_64 32-64
42 */
43 #define X86_HW_WATCHPOINT_DR6_DR0_BREAKPOINT_CONDITION_DETECTED __BIT(0)
44 #define X86_HW_WATCHPOINT_DR6_DR1_BREAKPOINT_CONDITION_DETECTED __BIT(1)
45 #define X86_HW_WATCHPOINT_DR6_DR2_BREAKPOINT_CONDITION_DETECTED __BIT(2)
46 #define X86_HW_WATCHPOINT_DR6_DR3_BREAKPOINT_CONDITION_DETECTED __BIT(3)
47 #define X86_HW_WATCHPOINT_DR6_DEBUG_REGISTER_ACCESS_DETECTED __BIT(13)
48 #define X86_HW_WATCHPOINT_DR6_SINGLE_STEP __BIT(14)
49 #define X86_HW_WATCHPOINT_DR6_TASK_SWITCH __BIT(15)
50
51 /*
52 * CPU Debug Control Register (DR7)
53 *
54 * LOCAL_EXACT_BREAKPOINT and GLOBAL_EXACT_BREAKPOINT are no longer used since
55 * the P6 processor family - portable code should set these bits
56 * unconditionally in oder to get exact breakpoints
57 *
58 * Reserved bits: 10, 12, 14-15 and on x86_64 32-64
59 */
60 #define X86_HW_WATCHPOINT_DR7_LOCAL_DR0_BREAKPOINT __BIT(0)
61 #define X86_HW_WATCHPOINT_DR7_GLOBAL_DR0_BREAKPOINT __BIT(1)
62 #define X86_HW_WATCHPOINT_DR7_LOCAL_DR1_BREAKPOINT __BIT(2)
63 #define X86_HW_WATCHPOINT_DR7_GLOBAL_DR1_BREAKPOINT __BIT(3)
64 #define X86_HW_WATCHPOINT_DR7_LOCAL_DR2_BREAKPOINT __BIT(4)
65 #define X86_HW_WATCHPOINT_DR7_GLOBAL_DR2_BREAKPOINT __BIT(5)
66 #define X86_HW_WATCHPOINT_DR7_LOCAL_DR3_BREAKPOINT __BIT(6)
67 #define X86_HW_WATCHPOINT_DR7_GLOBAL_DR3_BREAKPOINT __BIT(7)
68 #define X86_HW_WATCHPOINT_DR7_LOCAL_EXACT_BREAKPOINT __BIT(8)
69 #define X86_HW_WATCHPOINT_DR7_GLOBAL_EXACT_BREAKPOINT __BIT(9)
70 #define X86_HW_WATCHPOINT_DR7_RESTRICTED_TRANSACTIONAL_MEMORY __BIT(11)
71 #define X86_HW_WATCHPOINT_DR7_GENERAL_DETECT_ENABLE __BIT(13)
72
73 #define X86_HW_WATCHPOINT_DR7_DR0_CONDITION_MASK __BITS(16, 17)
74 #define X86_HW_WATCHPOINT_DR7_DR0_LENGTH_MASK __BITS(18, 19)
75 #define X86_HW_WATCHPOINT_DR7_DR1_CONDITION_MASK __BITS(20, 21)
76 #define X86_HW_WATCHPOINT_DR7_DR1_LENGTH_MASK __BITS(22, 23)
77 #define X86_HW_WATCHPOINT_DR7_DR2_CONDITION_MASK __BITS(24, 25)
78 #define X86_HW_WATCHPOINT_DR7_DR2_LENGTH_MASK __BITS(26, 27)
79 #define X86_HW_WATCHPOINT_DR7_DR3_CONDITION_MASK __BITS(28, 29)
80 #define X86_HW_WATCHPOINT_DR7_DR3_LENGTH_MASK __BITS(30, 31)
81
82 #endif /* !defined(_KERNEL) */
83
84 /*
85 * X86_HW_WATCHPOINT_DR7_CONDITION_IO_READWRITE is currently unused
86 * it requires DE (debug extension) flag in control register CR4 set
87 * not all CPUs support it
88 */
89 enum x86_hw_watchpoint_condition {
90 X86_HW_WATCHPOINT_DR7_CONDITION_EXECUTION = 0x0,
91 X86_HW_WATCHPOINT_DR7_CONDITION_DATA_WRITE = 0x1,
92 X86_HW_WATCHPOINT_DR7_CONDITION_IO_READWRITE = 0x2,
93 X86_HW_WATCHPOINT_DR7_CONDITION_DATA_READWRITE = 0x3
94 };
95
96 /*
97 * 0x2 is currently unimplemented - it reflects 8 bytes on modern CPUs
98 */
99 enum x86_hw_watchpoint_length {
100 X86_HW_WATCHPOINT_DR7_LENGTH_BYTE = 0x0,
101 X86_HW_WATCHPOINT_DR7_LENGTH_TWOBYTES = 0x1,
102 /* 0x2 undefined */
103 X86_HW_WATCHPOINT_DR7_LENGTH_FOURBYTES = 0x3
104 };
105
106 /*
107 * 0x2 is currently unimplemented - it reflects 8 bytes on modern CPUs
108 */
109 enum x86_hw_watchpoint_event {
110 X86_HW_WATCHPOINT_EVENT_NONE = 0x0,
111 X86_HW_WATCHPOINT_EVENT_FIRED = 0x1,
112 X86_HW_WATCHPOINT_EVENT_FIRED_AND_SSTEP = 0x2,
113 };
114
115 #if defined(_KMEMUSER) || defined(_KERNEL)
116
117 /*
118 * The number of available watchpoint registers available since Intel 80386
119 * New CPUs ship with up to 16 Debug Registers but they still offer four
120 * watchpoints, while there other registers are reserved
121 */
122 #define X86_HW_WATCHPOINTS 4
123
124 /*
125 * lwpid - 0 means all LWPs in the process
126 * address - 0 means that watchpoint is disabled
127 */
128 struct x86_hw_watchpoint {
129 vaddr_t address;
130 enum x86_hw_watchpoint_condition condition;
131 enum x86_hw_watchpoint_length length;
132 };
133
134 #endif /* !defined(_KMEMUSER) && !defined(_KERNEL) */
135
136 #if defined(_KERNEL)
137 /*
138 * Set CPU Debug Registers - to be used before entering user-land context
139 */
140 void set_x86_hw_watchpoints(struct lwp *l);
141
142 /*
143 * Reset CPU Debug Registers - to be used after entering kernel context
144 */
145 void clear_x86_hw_watchpoints(void);
146
147 /*
148 * Check if trap is triggered from user-land if so return nonzero value
149 */
150 int user_trap_x86_hw_watchpoint(void);
151
152 /*
153 * Check if trap is triggered from user-land if so return nonzero value
154 */
155 int x86_hw_watchpoint_type(int);
156
157 /*
158 * Return register that fired
159 */
160 int x86_hw_watchpoint_reg(int);
161
162 #endif /* !defined(_KERNEL) */
163
164 #endif /* !_X86_DBREGS_H_ */
165