aarch64 doesn't have native store immediate instruction, such operation
has to be implemented by the below instruction sequence:

Load immediate to register
Store register

Signed-off-by: Yang Shi <yang....@linaro.org>
CC: Zi Shen Lim <zlim....@gmail.com>
CC: Xi Wang <xi.w...@gmail.com>
---
Thsi patch might be buried by the storm of xadd discussion, however, it is
absolutely irrelevent to xadd, so resend the patch itself.

 arch/arm64/net/bpf_jit_comp.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index 6809647..49c1f1b 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -563,7 +563,25 @@ emit_cond_jmp:
        case BPF_ST | BPF_MEM | BPF_H:
        case BPF_ST | BPF_MEM | BPF_B:
        case BPF_ST | BPF_MEM | BPF_DW:
-               goto notyet;
+               /* Load imm to a register then store it */
+               ctx->tmp_used = 1;
+               emit_a64_mov_i(1, tmp2, off, ctx);
+               emit_a64_mov_i(1, tmp, imm, ctx);
+               switch (BPF_SIZE(code)) {
+               case BPF_W:
+                       emit(A64_STR32(tmp, dst, tmp2), ctx);
+                       break;
+               case BPF_H:
+                       emit(A64_STRH(tmp, dst, tmp2), ctx);
+                       break;
+               case BPF_B:
+                       emit(A64_STRB(tmp, dst, tmp2), ctx);
+                       break;
+               case BPF_DW:
+                       emit(A64_STR64(tmp, dst, tmp2), ctx);
+                       break;
+               }
+               break;
 
        /* STX: *(size *)(dst + off) = src */
        case BPF_STX | BPF_MEM | BPF_W:
-- 
2.0.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to