[PATCH v2 4/8] powerpc/ppc-opcode: introduce PPC_RAW_BRANCH() macro

[LEROY Christophe]

Le 17/09/2021 à 17:30, Hari Bathini a écrit :
> Define and use PPC_RAW_BRANCH() macro instead of open coding it. This
> macro is used while adding BPF_PROBE_MEM support.
> 
> Signed-off-by: Hari Bathini <hbathini at linux.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>

> ---
> 
> Changes in v2:
> * New patch to introduce PPC_RAW_BRANCH() macro.
> 
> 
>   arch/powerpc/include/asm/ppc-opcode.h | 2 ++
>   arch/powerpc/net/bpf_jit.h            | 4 ++--
>   2 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
> index baea657bc868..f50213e2a3e0 100644
> --- a/arch/powerpc/include/asm/ppc-opcode.h
> +++ b/arch/powerpc/include/asm/ppc-opcode.h
> @@ -566,6 +566,8 @@
>   #define PPC_RAW_MTSPR(spr, d)		(0x7c0003a6 | ___PPC_RS(d) | __PPC_SPR(spr))
>   #define PPC_RAW_EIEIO()			(0x7c0006ac)
>   
> +#define PPC_RAW_BRANCH(addr)		(PPC_INST_BRANCH | ((addr) & 0x03fffffc))
> +
>   /* Deal with instructions that older assemblers aren't aware of */
>   #define	PPC_BCCTR_FLUSH		stringify_in_c(.long PPC_INST_BCCTR_FLUSH)
>   #define	PPC_CP_ABORT		stringify_in_c(.long PPC_RAW_CP_ABORT)
> diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
> index 411c63d945c7..0c8f885b8f48 100644
> --- a/arch/powerpc/net/bpf_jit.h
> +++ b/arch/powerpc/net/bpf_jit.h
> @@ -24,8 +24,8 @@
>   #define EMIT(instr)		PLANT_INSTR(image, ctx->idx, instr)
>   
>   /* Long jump; (unconditional 'branch') */
> -#define PPC_JMP(dest)		EMIT(PPC_INST_BRANCH |			      \
> -				     (((dest) - (ctx->idx * 4)) & 0x03fffffc))
> +#define PPC_JMP(dest)		EMIT(PPC_RAW_BRANCH((dest) - (ctx->idx * 4)))
> +
>   /* blr; (unconditional 'branch' with link) to absolute address */
>   #define PPC_BL_ABS(dest)	EMIT(PPC_INST_BL |			      \
>   				     (((dest) - (unsigned long)(image + ctx->idx)) & 0x03fffffc))
>