The coming x86 refcount protection needs to be able to add trailing
instructions to the GEN_*_RMWcc() operations. This extracts the
difference between the goto/non-goto cases so the helper macros
can be defined outside the #ifdef cases. Additionally adds argument
naming to the resulting asm for referencing from suffixed
instructions.
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
arch/x86/include/asm/rmwcc.h | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/rmwcc.h b/arch/x86/include/asm/rmwcc.h
index 661dd305694a..3e96f9a56b6d 100644
--- a/arch/x86/include/asm/rmwcc.h
+++ b/arch/x86/include/asm/rmwcc.h
@@ -8,18 +8,15 @@
#define __GEN_RMWcc(fullop, var, cc, ...) \
do { \
asm_volatile_goto (fullop "; j" #cc " %l[cc_label]" \
- : : "m" (var), ## __VA_ARGS__ \
+ : : [counter] "m" (var), ## __VA_ARGS__ \
: "memory" : cc_label); \
return 0; \
cc_label: \
return 1; \
} while (0)
-#define GEN_UNARY_RMWcc(op, var, arg0, cc) \
- __GEN_RMWcc(op " " arg0, var, cc)
+#define __BINARY_RMWcc_ARG " %1, "
-#define GEN_BINARY_RMWcc(op, var, vcon, val, arg0, cc) \
- __GEN_RMWcc(op " %1, " arg0, var, cc, vcon (val))
#else /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */
@@ -29,17 +26,26 @@ cc_label:
\
do { \
bool c; \
asm volatile (fullop ";" CC_SET(cc) \
- : "+m" (var), CC_OUT(cc) (c) \
+ : [counter] "+m" (var), CC_OUT(cc) (c) \
: __VA_ARGS__ : "memory"); \
return c; \
} while (0)
+#define __BINARY_RMWcc_ARG " %2, "
+
+#endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */
+
#define GEN_UNARY_RMWcc(op, var, arg0, cc) \
__GEN_RMWcc(op " " arg0, var, cc)
+#define GEN_UNARY_SUFFIXED_RMWcc(op, suffix, var, arg0, cc) \
+ __GEN_RMWcc(op " " arg0 "\n\t" suffix, var, cc)
+
#define GEN_BINARY_RMWcc(op, var, vcon, val, arg0, cc) \
- __GEN_RMWcc(op " %2, " arg0, var, cc, vcon (val))
+ __GEN_RMWcc(op __BINARY_RMWcc_ARG arg0, var, cc, vcon (val))
-#endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */
+#define GEN_BINARY_SUFFIXED_RMWcc(op, suffix, var, vcon, val, arg0, cc)
\
+ __GEN_RMWcc(op __BINARY_RMWcc_ARG arg0 "\n\t" suffix, var, cc, \
+ vcon (val))
#endif /* _ASM_X86_RMWcc */
--
2.7.4
