From 50e51c13b3822d14ff6df4279423e4b7b2269bc3 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 10 Jan 2018 03:07:15 +1100 Subject: [PATCH] powerpc/64: Add macros for annotating the destination of rfid/hrfid The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is used for switching from the kernel to userspace, and from the hypervisor to the guest kernel. However it can and is also used for other transitions, eg. from real mode kernel code to virtual mode kernel code, and it's not always clear from the code what the destination context is. To make it clearer when reading the code, add macros which encode the expected destination context. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/exception-64e.h | 6 +++++ arch/powerpc/include/asm/exception-64s.h | 29 ++++++++++++++++++++++++ 2 files changed, 35 insertions(+) diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h index a703452d67b6..555e22d5e07f 100644 --- a/arch/powerpc/include/asm/exception-64e.h +++ b/arch/powerpc/include/asm/exception-64e.h @@ -209,5 +209,11 @@ exc_##label##_book3e: ori r3,r3,vector_offset@l; \ mtspr SPRN_IVOR##vector_number,r3; +#define RFI_TO_KERNEL \ + rfi + +#define RFI_TO_USER \ + rfi + #endif /* _ASM_POWERPC_EXCEPTION_64E_H */ diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index b27205297e1d..1af427a3c74f 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -74,6 +74,35 @@ */ #define EX_R3 EX_DAR +/* Macros for annotating the expected destination of (h)rfid */ + +#define RFI_TO_KERNEL \ + rfid + +#define RFI_TO_USER \ + rfid + +#define RFI_TO_USER_OR_KERNEL \ + rfid + +#define RFI_TO_GUEST \ + rfid + +#define HRFI_TO_KERNEL \ + hrfid + +#define HRFI_TO_USER \ + hrfid + +#define HRFI_TO_USER_OR_KERNEL \ + hrfid + +#define HRFI_TO_GUEST \ + hrfid + +#define HRFI_TO_UNKNOWN \ + hrfid + #ifdef CONFIG_RELOCATABLE #define __EXCEPTION_RELON_PROLOG_PSERIES_1(label, h) \ mfspr r11,SPRN_##h##SRR0; /* save SRR0 */ \