[PATCH V4 38/50] x86/entry: Add a C macro to define the function body for IST in .entry.text

From: Lai Jiangshan
Date: Tue Oct 26 2021 - 10:36:29 EST


From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>

Add DEFINE_IDTENTRY_IST_ETNRY() macro to define C code to implement
the ASM code which calls paranoid_entry(), cfunc(), paranoid_exit()
in series for IST exceptions without error code.

Not functional difference intended.

Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/idtentry.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index cf41901227ed..0f615943a460 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -337,6 +337,20 @@ void ist_paranoid_exit(unsigned long cr3, unsigned long gsbase);
__visible noinstr void kernel_##func(struct pt_regs *regs, unsigned long error_code); \
__visible noinstr void user_##func(struct pt_regs *regs, unsigned long error_code)

+/**
+ * DEFINE_IDTENTRY_IST_ENTRY - Emit __entry_text code for IST entry points
+ * @func: Function name of the entry point
+ */
+#define DEFINE_IDTENTRY_IST_ETNRY(func) \
+__visible __entry_text void ist_##func(struct pt_regs *regs) \
+{ \
+ unsigned long cr3, gsbase; \
+ \
+ ist_paranoid_entry(&cr3, &gsbase); \
+ func(regs); \
+ ist_paranoid_exit(cr3, gsbase); \
+}
+
/**
* DEFINE_IDTENTRY_IST - Emit code for IST entry points
* @func: Function name of the entry point
--
2.19.1.6.gb485710b