arch/arm64/include/asm/debug-monitors.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 ARM Ltd.
   4  */
   5 #ifndef __ASM_DEBUG_MONITORS_H
   6 #define __ASM_DEBUG_MONITORS_H
   7
   8 #ifdef __KERNEL__
   9
  10 #include <linux/errno.h>
  11 #include <linux/types.h>
  12 #include <asm/brk-imm.h>
  13 #include <asm/esr.h>
  14 #include <asm/insn.h>
  15 #include <asm/ptrace.h>
  16
  17 /* Low-level stepping controls. */
  18 #define DBG_MDSCR_SS            (1 << 0)
  19 #define DBG_SPSR_SS             (1 << 21)
  20
  21 /* MDSCR_EL1 enabling bits */
  22 #define DBG_MDSCR_KDE           (1 << 13)
  23 #define DBG_MDSCR_MDE           (1 << 15)
  24 #define DBG_MDSCR_MASK          ~(DBG_MDSCR_KDE | DBG_MDSCR_MDE)
  25
  26 #define DBG_ESR_EVT(x)          (((x) >> 27) & 0x7)
  27
  28 /* AArch64 */
  29 #define DBG_ESR_EVT_HWBP        0x0
  30 #define DBG_ESR_EVT_HWSS        0x1
  31 #define DBG_ESR_EVT_HWWP        0x2
  32 #define DBG_ESR_EVT_BRK         0x6
  33
  34 /*
  35  * Break point instruction encoding
  36  */
  37 #define BREAK_INSTR_SIZE                AARCH64_INSN_SIZE
  38
  39 /*
  40  * BRK instruction encoding
  41  * The #imm16 value should be placed at bits[20:5] within BRK ins
  42  */
  43 #define AARCH64_BREAK_MON       0xd4200000
  44
  45 /*
  46  * BRK instruction for provoking a fault on purpose
  47  * Unlike kgdb, #imm16 value with unallocated handler is used for faulting.
  48  */
  49 #define AARCH64_BREAK_FAULT     (AARCH64_BREAK_MON | (FAULT_BRK_IMM << 5))
  50
  51 #define AARCH64_BREAK_KGDB_DYN_DBG      \
  52         (AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5))
  53
  54 #define CACHE_FLUSH_IS_SAFE             1
  55
  56 /* kprobes BRK opcodes with ESR encoding  */
  57 #define BRK64_OPCODE_KPROBES    (AARCH64_BREAK_MON | (KPROBES_BRK_IMM << 5))
  58 /* uprobes BRK opcodes with ESR encoding  */
  59 #define BRK64_OPCODE_UPROBES    (AARCH64_BREAK_MON | (UPROBES_BRK_IMM << 5))
  60
  61 /* AArch32 */
  62 #define DBG_ESR_EVT_BKPT        0x4
  63 #define DBG_ESR_EVT_VECC        0x5
  64
  65 #define AARCH32_BREAK_ARM       0x07f001f0
  66 #define AARCH32_BREAK_THUMB     0xde01
  67 #define AARCH32_BREAK_THUMB2_LO 0xf7f0
  68 #define AARCH32_BREAK_THUMB2_HI 0xa000
  69
  70 #ifndef __ASSEMBLY__
  71 struct task_struct;
  72
  73 #define DBG_ARCH_ID_RESERVED    0       /* In case of ptrace ABI updates. */
  74
  75 #define DBG_HOOK_HANDLED        0
  76 #define DBG_HOOK_ERROR          1
  77
  78 struct step_hook {
  79         struct list_head node;
  80         int (*fn)(struct pt_regs *regs, unsigned int esr);
  81 };
  82
  83 void register_user_step_hook(struct step_hook *hook);
  84 void unregister_user_step_hook(struct step_hook *hook);
  85
  86 void register_kernel_step_hook(struct step_hook *hook);
  87 void unregister_kernel_step_hook(struct step_hook *hook);
  88
  89 struct break_hook {
  90         struct list_head node;
  91         int (*fn)(struct pt_regs *regs, unsigned int esr);
  92         u16 imm;
  93         u16 mask; /* These bits are ignored when comparing with imm */
  94 };
  95
  96 void register_user_break_hook(struct break_hook *hook);
  97 void unregister_user_break_hook(struct break_hook *hook);
  98
  99 void register_kernel_break_hook(struct break_hook *hook);
 100 void unregister_kernel_break_hook(struct break_hook *hook);
 101
 102 u8 debug_monitors_arch(void);
 103
 104 enum dbg_active_el {
 105         DBG_ACTIVE_EL0 = 0,
 106         DBG_ACTIVE_EL1,
 107 };
 108
 109 void enable_debug_monitors(enum dbg_active_el el);
 110 void disable_debug_monitors(enum dbg_active_el el);
 111
 112 void user_rewind_single_step(struct task_struct *task);
 113 void user_fastforward_single_step(struct task_struct *task);
 114
 115 void kernel_enable_single_step(struct pt_regs *regs);
 116 void kernel_disable_single_step(void);
 117 int kernel_active_single_step(void);
 118
 119 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 120 int reinstall_suspended_bps(struct pt_regs *regs);
 121 #else
 122 static inline int reinstall_suspended_bps(struct pt_regs *regs)
 123 {
 124         return -ENODEV;
 125 }
 126 #endif
 127
 128 int aarch32_break_handler(struct pt_regs *regs);
 129
 130 #endif  /* __ASSEMBLY */
 131 #endif  /* __KERNEL__ */
 132 #endif  /* __ASM_DEBUG_MONITORS_H */