LXR linux/arch/powerpc/include/asm/bug.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASM_POWERPC_BUG_H
   3#define _ASM_POWERPC_BUG_H
   4#ifdef __KERNEL__
   5
   6#include <asm/asm-compat.h>
   7
   8/*
   9 * Define an illegal instr to trap on the bug.
  10 * We don't use 0 because that marks the end of a function
  11 * in the ELF ABI.  That's "Boo Boo" in case you wonder...
  12 */
  13#define BUG_OPCODE .long 0x00b00b00  /* For asm */
  14#define BUG_ILLEGAL_INSTR "0x00b00b00" /* For BUG macro */
  15
  16#ifdef CONFIG_BUG
  17
  18#ifdef __ASSEMBLY__
  19#include <asm/asm-offsets.h>
  20#ifdef CONFIG_DEBUG_BUGVERBOSE
  21.macro EMIT_BUG_ENTRY addr,file,line,flags
  22         .section __bug_table,"aw"
  235001:    PPC_LONG \addr, 5002f
  24         .short \line, \flags
  25         .org 5001b+BUG_ENTRY_SIZE
  26         .previous
  27         .section .rodata,"a"
  285002:    .asciz "\file"
  29         .previous
  30.endm
  31#else
  32.macro EMIT_BUG_ENTRY addr,file,line,flags
  33         .section __bug_table,"aw"
  345001:    PPC_LONG \addr
  35         .short \flags
  36         .org 5001b+BUG_ENTRY_SIZE
  37         .previous
  38.endm
  39#endif /* verbose */
  40
  41#else /* !__ASSEMBLY__ */
  42/* _EMIT_BUG_ENTRY expects args %0,%1,%2,%3 to be FILE, LINE, flags and
  43   sizeof(struct bug_entry), respectively */
  44#ifdef CONFIG_DEBUG_BUGVERBOSE
  45#define _EMIT_BUG_ENTRY                         \
  46        ".section __bug_table,\"aw\"\n"         \
  47        "2:\t" PPC_LONG "1b, %0\n"              \
  48        "\t.short %1, %2\n"                     \
  49        ".org 2b+%3\n"                          \
  50        ".previous\n"
  51#else
  52#define _EMIT_BUG_ENTRY                         \
  53        ".section __bug_table,\"aw\"\n"         \
  54        "2:\t" PPC_LONG "1b\n"                  \
  55        "\t.short %2\n"                         \
  56        ".org 2b+%3\n"                          \
  57        ".previous\n"
  58#endif
  59
  60/*
  61 * BUG_ON() and WARN_ON() do their best to cooperate with compile-time
  62 * optimisations. However depending on the complexity of the condition
  63 * some compiler versions may not produce optimal results.
  64 */
  65
  66#define BUG() do {                                              \
  67        __asm__ __volatile__(                                   \
  68                "1:     twi 31,0,0\n"                           \
  69                _EMIT_BUG_ENTRY                                 \
  70                : : "i" (__FILE__), "i" (__LINE__),             \
  71                    "i" (0), "i"  (sizeof(struct bug_entry)));  \
  72        unreachable();                                          \
  73} while (0)
  74
  75#define BUG_ON(x) do {                                          \
  76        if (__builtin_constant_p(x)) {                          \
  77                if (x)                                          \
  78                        BUG();                                  \
  79        } else {                                                \
  80                __asm__ __volatile__(                           \
  81                "1:     "PPC_TLNEI"     %4,0\n"                 \
  82                _EMIT_BUG_ENTRY                                 \
  83                : : "i" (__FILE__), "i" (__LINE__), "i" (0),    \
  84                  "i" (sizeof(struct bug_entry)),               \
  85                  "r" ((__force long)(x)));                     \
  86        }                                                       \
  87} while (0)
  88
  89#define __WARN_FLAGS(flags) do {                                \
  90        __asm__ __volatile__(                                   \
  91                "1:     twi 31,0,0\n"                           \
  92                _EMIT_BUG_ENTRY                                 \
  93                : : "i" (__FILE__), "i" (__LINE__),             \
  94                  "i" (BUGFLAG_WARNING|(flags)),                \
  95                  "i" (sizeof(struct bug_entry)));              \
  96} while (0)
  97
  98#define WARN_ON(x) ({                                           \
  99        int __ret_warn_on = !!(x);                              \
 100        if (__builtin_constant_p(__ret_warn_on)) {              \
 101                if (__ret_warn_on)                              \
 102                        __WARN();                               \
 103        } else {                                                \
 104                __asm__ __volatile__(                           \
 105                "1:     "PPC_TLNEI"     %4,0\n"                 \
 106                _EMIT_BUG_ENTRY                                 \
 107                : : "i" (__FILE__), "i" (__LINE__),             \
 108                  "i" (BUGFLAG_WARNING|BUGFLAG_TAINT(TAINT_WARN)),\
 109                  "i" (sizeof(struct bug_entry)),               \
 110                  "r" (__ret_warn_on));                         \
 111        }                                                       \
 112        unlikely(__ret_warn_on);                                \
 113})
 114
 115#define HAVE_ARCH_BUG
 116#define HAVE_ARCH_BUG_ON
 117#define HAVE_ARCH_WARN_ON
 118#endif /* __ASSEMBLY __ */
 119#else
 120#ifdef __ASSEMBLY__
 121.macro EMIT_BUG_ENTRY addr,file,line,flags
 122.endm
 123#else /* !__ASSEMBLY__ */
 124#define _EMIT_BUG_ENTRY
 125#endif
 126#endif /* CONFIG_BUG */
 127
 128#include <asm-generic/bug.h>
 129
 130#ifndef __ASSEMBLY__
 131
 132struct pt_regs;
 133extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 134extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 135extern void _exception(int, struct pt_regs *, int, unsigned long);
 136extern void _exception_pkey(int, struct pt_regs *, int, unsigned long, int);
 137extern void die(const char *, struct pt_regs *, long);
 138extern bool die_will_crash(void);
 139extern void panic_flush_kmsg_start(void);
 140extern void panic_flush_kmsg_end(void);
 141#endif /* !__ASSEMBLY__ */
 142
 143#endif /* __KERNEL__ */
 144#endif /* _ASM_POWERPC_BUG_H */
 145