[PATCH v2 10/12] x86/paravirt: add new macros PVOP_ALT* supporting pvops in ALTERNATIVEs

From: Juergen Gross
Date: Fri Nov 20 2020 - 06:47:05 EST


Instead of using paravirt patching for custom code sequences add
support for using ALTERNATIVE handling combined with paravirt call
patching.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
arch/x86/include/asm/paravirt_types.h | 62 +++++++++++++++++++++++++++
1 file changed, 62 insertions(+)

diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index b66650dc869e..1f8e1b76e78b 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -482,14 +482,39 @@ int paravirt_disable_iospace(void);
(rettype)(__eax & PVOP_RETMASK(rettype)); \
})

+#define ____PVOP_ALT_CALL(rettype, op, alt, cond, clbr, call_clbr, \
+ extra_clbr, ...) \
+ ({ \
+ PVOP_CALL_ARGS; \
+ PVOP_TEST_NULL(op); \
+ BUILD_BUG_ON(sizeof(rettype) > sizeof(unsigned long)); \
+ asm volatile(ALTERNATIVE(paravirt_alt(PARAVIRT_CALL), \
+ alt, cond) \
+ : call_clbr, ASM_CALL_CONSTRAINT \
+ : paravirt_type(op), \
+ paravirt_clobber(clbr), \
+ ##__VA_ARGS__ \
+ : "memory", "cc" extra_clbr); \
+ (rettype)(__eax & PVOP_RETMASK(rettype)); \
+ })
+
#define __PVOP_CALL(rettype, op, ...) \
____PVOP_CALL(rettype, op, CLBR_ANY, PVOP_CALL_CLOBBERS, \
EXTRA_CLOBBERS, ##__VA_ARGS__)

+#define __PVOP_ALT_CALL(rettype, op, alt, cond, ...) \
+ ____PVOP_ALT_CALL(rettype, op, alt, cond, CLBR_ANY, \
+ PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS, \
+ ##__VA_ARGS__)
+
#define __PVOP_CALLEESAVE(rettype, op, ...) \
____PVOP_CALL(rettype, op.func, CLBR_RET_REG, \
PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)

+#define __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, ...) \
+ ____PVOP_ALT_CALL(rettype, op.func, alt, cond, CLBR_RET_REG, \
+ PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)
+

#define ____PVOP_VCALL(op, clbr, call_clbr, extra_clbr, ...) \
({ \
@@ -503,36 +528,73 @@ int paravirt_disable_iospace(void);
: "memory", "cc" extra_clbr); \
})

+#define ____PVOP_ALT_VCALL(op, alt, cond, clbr, call_clbr, \
+ extra_clbr, ...) \
+ ({ \
+ PVOP_VCALL_ARGS; \
+ PVOP_TEST_NULL(op); \
+ asm volatile(ALTERNATIVE(paravirt_alt(PARAVIRT_CALL), \
+ alt, cond) \
+ : call_clbr, ASM_CALL_CONSTRAINT \
+ : paravirt_type(op), \
+ paravirt_clobber(clbr), \
+ ##__VA_ARGS__ \
+ : "memory", "cc" extra_clbr); \
+ })
+
#define __PVOP_VCALL(op, ...) \
____PVOP_VCALL(op, CLBR_ANY, PVOP_VCALL_CLOBBERS, \
VEXTRA_CLOBBERS, ##__VA_ARGS__)

+#define __PVOP_ALT_VCALL(op, alt, cond, ...) \
+ ____PVOP_ALT_VCALL(op, alt, cond, CLBR_ANY, \
+ PVOP_VCALL_CLOBBERS, VEXTRA_CLOBBERS, \
+ ##__VA_ARGS__)
+
#define __PVOP_VCALLEESAVE(op, ...) \
____PVOP_VCALL(op.func, CLBR_RET_REG, \
PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)

+#define __PVOP_ALT_VCALLEESAVE(op, alt, cond, ...) \
+ ____PVOP_ALT_VCALL(op.func, alt, cond, CLBR_RET_REG, \
+ PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)
+


#define PVOP_CALL0(rettype, op) \
__PVOP_CALL(rettype, op)
#define PVOP_VCALL0(op) \
__PVOP_VCALL(op)
+#define PVOP_ALT_CALL0(rettype, op, alt, cond) \
+ __PVOP_ALT_CALL(rettype, op, alt, cond)
+#define PVOP_ALT_VCALL0(op, alt, cond) \
+ __PVOP_ALT_VCALL(op, alt, cond)

#define PVOP_CALLEE0(rettype, op) \
__PVOP_CALLEESAVE(rettype, op)
#define PVOP_VCALLEE0(op) \
__PVOP_VCALLEESAVE(op)
+#define PVOP_ALT_CALLEE0(rettype, op, alt, cond) \
+ __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond)
+#define PVOP_ALT_VCALLEE0(op, alt, cond) \
+ __PVOP_ALT_VCALLEESAVE(op, alt, cond)


#define PVOP_CALL1(rettype, op, arg1) \
__PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1))
#define PVOP_VCALL1(op, arg1) \
__PVOP_VCALL(op, PVOP_CALL_ARG1(arg1))
+#define PVOP_ALT_VCALL1(op, arg1, alt, cond) \
+ __PVOP_ALT_VCALL(op, alt, cond, PVOP_CALL_ARG1(arg1))

#define PVOP_CALLEE1(rettype, op, arg1) \
__PVOP_CALLEESAVE(rettype, op, PVOP_CALL_ARG1(arg1))
#define PVOP_VCALLEE1(op, arg1) \
__PVOP_VCALLEESAVE(op, PVOP_CALL_ARG1(arg1))
+#define PVOP_ALT_CALLEE1(rettype, op, arg1, alt, cond) \
+ __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, PVOP_CALL_ARG1(arg1))
+#define PVOP_ALT_VCALLEE1(op, arg1, alt, cond) \
+ __PVOP_ALT_VCALLEESAVE(op, alt, cond, PVOP_CALL_ARG1(arg1))


#define PVOP_CALL2(rettype, op, arg1, arg2) \
--
2.26.2