arch/riscv/include/asm/asm-extable.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 #ifndef __ASM_ASM_EXTABLE_H
   3 #define __ASM_ASM_EXTABLE_H
   4
   5 #define EX_TYPE_NONE                    0
   6 #define EX_TYPE_FIXUP                   1
   7 #define EX_TYPE_BPF                     2
   8 #define EX_TYPE_UACCESS_ERR_ZERO        3
   9 #define EX_TYPE_LOAD_UNALIGNED_ZEROPAD  4
  10
  11 #ifdef CONFIG_MMU
  12
  13 #ifdef __ASSEMBLY__
  14
  15 #define __ASM_EXTABLE_RAW(insn, fixup, type, data)      \
  16         .pushsection    __ex_table, "a";                \
  17         .balign         4;                              \
  18         .long           ((insn) - .);                   \
  19         .long           ((fixup) - .);                  \
  20         .short          (type);                         \
  21         .short          (data);                         \
  22         .popsection;
  23
  24         .macro          _asm_extable, insn, fixup
  25         __ASM_EXTABLE_RAW(\insn, \fixup, EX_TYPE_FIXUP, 0)
  26         .endm
  27
  28 #else /* __ASSEMBLY__ */
  29
  30 #include <linux/bits.h>
  31 #include <linux/stringify.h>
  32 #include <asm/gpr-num.h>
  33
  34 #define __ASM_EXTABLE_RAW(insn, fixup, type, data)      \
  35         ".pushsection   __ex_table, \"a\"\n"            \
  36         ".balign        4\n"                            \
  37         ".long          ((" insn ") - .)\n"             \
  38         ".long          ((" fixup ") - .)\n"            \
  39         ".short         (" type ")\n"                   \
  40         ".short         (" data ")\n"                   \
  41         ".popsection\n"
  42
  43 #define _ASM_EXTABLE(insn, fixup)       \
  44         __ASM_EXTABLE_RAW(#insn, #fixup, __stringify(EX_TYPE_FIXUP), "0")
  45
  46 #define EX_DATA_REG_ERR_SHIFT   0
  47 #define EX_DATA_REG_ERR         GENMASK(4, 0)
  48 #define EX_DATA_REG_ZERO_SHIFT  5
  49 #define EX_DATA_REG_ZERO        GENMASK(9, 5)
  50
  51 #define EX_DATA_REG_DATA_SHIFT  0
  52 #define EX_DATA_REG_DATA        GENMASK(4, 0)
  53 #define EX_DATA_REG_ADDR_SHIFT  5
  54 #define EX_DATA_REG_ADDR        GENMASK(9, 5)
  55
  56 #define EX_DATA_REG(reg, gpr)                                           \
  57         "((.L__gpr_num_" #gpr ") << " __stringify(EX_DATA_REG_##reg##_SHIFT) ")"
  58
  59 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)           \
  60         __DEFINE_ASM_GPR_NUMS                                           \
  61         __ASM_EXTABLE_RAW(#insn, #fixup,                                \
  62                           __stringify(EX_TYPE_UACCESS_ERR_ZERO),        \
  63                           "("                                           \
  64                             EX_DATA_REG(ERR, err) " | "                 \
  65                             EX_DATA_REG(ZERO, zero)                     \
  66                           ")")
  67
  68 #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err)                      \
  69         _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)
  70
  71 #define _ASM_EXTABLE_LOAD_UNALIGNED_ZEROPAD(insn, fixup, data, addr)            \
  72         __DEFINE_ASM_GPR_NUMS                                                   \
  73         __ASM_EXTABLE_RAW(#insn, #fixup,                                        \
  74                           __stringify(EX_TYPE_LOAD_UNALIGNED_ZEROPAD),          \
  75                           "("                                                   \
  76                             EX_DATA_REG(DATA, data) " | "                       \
  77                             EX_DATA_REG(ADDR, addr)                             \
  78                           ")")
  79
  80 #endif /* __ASSEMBLY__ */
  81
  82 #else /* CONFIG_MMU */
  83         #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err)
  84 #endif /* CONFIG_MMU */
  85
  86 #endif /* __ASM_ASM_EXTABLE_H */