arch/x86/include/asm/asm.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_ASM_H
   3 #define _ASM_X86_ASM_H
   4
   5 #ifdef __ASSEMBLY__
   6 # define __ASM_FORM(x)  x
   7 # define __ASM_FORM_RAW(x)     x
   8 # define __ASM_FORM_COMMA(x) x,
   9 #else
  10 # define __ASM_FORM(x)  " " #x " "
  11 # define __ASM_FORM_RAW(x)     #x
  12 # define __ASM_FORM_COMMA(x) " " #x ","
  13 #endif
  14
  15 #ifndef __x86_64__
  16 /* 32 bit */
  17 # define __ASM_SEL(a,b) __ASM_FORM(a)
  18 # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
  19 #else
  20 /* 64 bit */
  21 # define __ASM_SEL(a,b) __ASM_FORM(b)
  22 # define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
  23 #endif
  24
  25 #define __ASM_SIZE(inst, ...)   __ASM_SEL(inst##l##__VA_ARGS__, \
  26                                           inst##q##__VA_ARGS__)
  27 #define __ASM_REG(reg)         __ASM_SEL_RAW(e##reg, r##reg)
  28
  29 #define _ASM_PTR        __ASM_SEL(.long, .quad)
  30 #define _ASM_ALIGN      __ASM_SEL(.balign 4, .balign 8)
  31
  32 #define _ASM_MOV        __ASM_SIZE(mov)
  33 #define _ASM_INC        __ASM_SIZE(inc)
  34 #define _ASM_DEC        __ASM_SIZE(dec)
  35 #define _ASM_ADD        __ASM_SIZE(add)
  36 #define _ASM_SUB        __ASM_SIZE(sub)
  37 #define _ASM_XADD       __ASM_SIZE(xadd)
  38 #define _ASM_MUL        __ASM_SIZE(mul)
  39
  40 #define _ASM_AX         __ASM_REG(ax)
  41 #define _ASM_BX         __ASM_REG(bx)
  42 #define _ASM_CX         __ASM_REG(cx)
  43 #define _ASM_DX         __ASM_REG(dx)
  44 #define _ASM_SP         __ASM_REG(sp)
  45 #define _ASM_BP         __ASM_REG(bp)
  46 #define _ASM_SI         __ASM_REG(si)
  47 #define _ASM_DI         __ASM_REG(di)
  48
  49 /*
  50  * Macros to generate condition code outputs from inline assembly,
  51  * The output operand must be type "bool".
  52  */
  53 #ifdef __GCC_ASM_FLAG_OUTPUTS__
  54 # define CC_SET(c) "\n\t/* output condition code " #c "*/\n"
  55 # define CC_OUT(c) "=@cc" #c
  56 #else
  57 # define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n"
  58 # define CC_OUT(c) [_cc_ ## c] "=qm"
  59 #endif
  60
  61 /* Exception table entry */
  62 #ifdef __ASSEMBLY__
  63 # define _ASM_EXTABLE_HANDLE(from, to, handler)                 \
  64         .pushsection "__ex_table","a" ;                         \
  65         .balign 4 ;                                             \
  66         .long (from) - . ;                                      \
  67         .long (to) - . ;                                        \
  68         .long (handler) - . ;                                   \
  69         .popsection
  70
  71 # define _ASM_EXTABLE(from, to)                                 \
  72         _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
  73
  74 # define _ASM_EXTABLE_FAULT(from, to)                           \
  75         _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
  76
  77 # define _ASM_EXTABLE_EX(from, to)                              \
  78         _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
  79
  80 # define _ASM_EXTABLE_REFCOUNT(from, to)                        \
  81         _ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
  82
  83 # define _ASM_NOKPROBE(entry)                                   \
  84         .pushsection "_kprobe_blacklist","aw" ;                 \
  85         _ASM_ALIGN ;                                            \
  86         _ASM_PTR (entry);                                       \
  87         .popsection
  88
  89 .macro ALIGN_DESTINATION
  90         /* check for bad alignment of destination */
  91         movl %edi,%ecx
  92         andl $7,%ecx
  93         jz 102f                         /* already aligned */
  94         subl $8,%ecx
  95         negl %ecx
  96         subl %ecx,%edx
  97 100:    movb (%rsi),%al
  98 101:    movb %al,(%rdi)
  99         incq %rsi
 100         incq %rdi
 101         decl %ecx
 102         jnz 100b
 103 102:
 104         .section .fixup,"ax"
 105 103:    addl %ecx,%edx                  /* ecx is zerorest also */
 106         jmp copy_user_handle_tail
 107         .previous
 108
 109         _ASM_EXTABLE(100b,103b)
 110         _ASM_EXTABLE(101b,103b)
 111         .endm
 112
 113 #else
 114 # define _EXPAND_EXTABLE_HANDLE(x) #x
 115 # define _ASM_EXTABLE_HANDLE(from, to, handler)                 \
 116         " .pushsection \"__ex_table\",\"a\"\n"                  \
 117         " .balign 4\n"                                          \
 118         " .long (" #from ") - .\n"                              \
 119         " .long (" #to ") - .\n"                                \
 120         " .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n"    \
 121         " .popsection\n"
 122
 123 # define _ASM_EXTABLE(from, to)                                 \
 124         _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
 125
 126 # define _ASM_EXTABLE_FAULT(from, to)                           \
 127         _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
 128
 129 # define _ASM_EXTABLE_EX(from, to)                              \
 130         _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
 131
 132 # define _ASM_EXTABLE_REFCOUNT(from, to)                        \
 133         _ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
 134
 135 /* For C file, we already have NOKPROBE_SYMBOL macro */
 136 #endif
 137
 138 #ifndef __ASSEMBLY__
 139 #ifndef __BPF__
 140 /*
 141  * This output constraint should be used for any inline asm which has a "call"
 142  * instruction.  Otherwise the asm may be inserted before the frame pointer
 143  * gets set up by the containing function.  If you forget to do this, objtool
 144  * may print a "call without frame pointer save/setup" warning.
 145  */
 146 register unsigned long current_stack_pointer asm(_ASM_SP);
 147 #define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
 148 #endif
 149 #endif
 150
 151 #endif /* _ASM_X86_ASM_H */