x86/mm: Expand the exception table logic to allow new handling options

[firefly-linux-kernel-4.4.55.git] / arch / x86 / include / asm / asm.h

diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 189679aba703537393b87d699a4e11cbfe94e23c..f5063b6659eb37f1a835bc5e614cf251ac48e032 100644 (file)
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -44,19 +44,22 @@
 
 /* Exception table entry */
 #ifdef __ASSEMBLY__
-# define _ASM_EXTABLE(from,to)                                 \
+# define _ASM_EXTABLE_HANDLE(from, to, handler)                        \
        .pushsection "__ex_table","a" ;                         \
-       .balign 8 ;                                             \
+       .balign 4 ;                                             \
        .long (from) - . ;                                      \
        .long (to) - . ;                                        \
+       .long (handler) - . ;                                   \
        .popsection
 
-# define _ASM_EXTABLE_EX(from,to)                              \
-       .pushsection "__ex_table","a" ;                         \
-       .balign 8 ;                                             \
-       .long (from) - . ;                                      \
-       .long (to) - . + 0x7ffffff0 ;                           \
-       .popsection
+# define _ASM_EXTABLE(from, to)                                        \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
+
+# define _ASM_EXTABLE_FAULT(from, to)                          \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
+
+# define _ASM_EXTABLE_EX(from, to)                             \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
 
 # define _ASM_NOKPROBE(entry)                                  \
        .pushsection "_kprobe_blacklist","aw" ;                 \
@@ -89,19 +92,24 @@
        .endm
 
 #else
-# define _ASM_EXTABLE(from,to)                                 \
+# define _EXPAND_EXTABLE_HANDLE(x) #x
+# define _ASM_EXTABLE_HANDLE(from, to, handler)                        \
        " .pushsection \"__ex_table\",\"a\"\n"                  \
-       " .balign 8\n"                                          \
+       " .balign 4\n"                                          \
        " .long (" #from ") - .\n"                              \
        " .long (" #to ") - .\n"                                \
+       " .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n"    \
        " .popsection\n"
 
-# define _ASM_EXTABLE_EX(from,to)                              \
-       " .pushsection \"__ex_table\",\"a\"\n"                  \
-       " .balign 8\n"                                          \
-       " .long (" #from ") - .\n"                              \
-       " .long (" #to ") - . + 0x7ffffff0\n"                   \
-       " .popsection\n"
+# define _ASM_EXTABLE(from, to)                                        \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
+
+# define _ASM_EXTABLE_FAULT(from, to)                          \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
+
+# define _ASM_EXTABLE_EX(from, to)                             \
+       _ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
+
 /* For C file, we already have NOKPROBE_SYMBOL macro */
 #endif