From patchwork series 482327

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=482327

Author: Fox Snowpatch

arch/powerpc/net/bpf_jit_comp.c

@@ -466,6 +466,22 @@ bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena)
 	return true;
 }
 
+bool bpf_jit_supports_percpu_insn(void)
+{
+	return IS_ENABLED(CONFIG_PPC64);
+}
+
+bool bpf_jit_inlines_helper_call(s32 imm)
+{
+	switch (imm) {
+	case BPF_FUNC_get_smp_processor_id:
+	case BPF_FUNC_get_current_task:
+		return true;
+	default:
+		return false;
+	}
+}
+
 void *arch_alloc_bpf_trampoline(unsigned int size)
 {
 	return bpf_prog_pack_alloc(size, bpf_jit_fill_ill_insns);

arch/powerpc/net/bpf_jit_comp64.c

@@ -918,6 +918,15 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code
 		case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */
 		case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */
 
+			if (insn_is_mov_percpu_addr(&insn[i])) {
+				if (IS_ENABLED(CONFIG_SMP)) {
+					EMIT(PPC_RAW_LD(tmp1_reg, _R13, offsetof(struct paca_struct, data_offset)));
+					EMIT(PPC_RAW_ADD(dst_reg, src_reg, tmp1_reg));
+				} else {
+					EMIT(PPC_RAW_MR(dst_reg, src_reg));
+				}
+			}
+
 			if (insn_is_cast_user(&insn[i])) {
 				EMIT(PPC_RAW_RLDICL_DOT(tmp1_reg, src_reg, 0, 32));
 				PPC_LI64(dst_reg, (ctx->user_vm_start & 0xffffffff00000000UL));
@@ -1390,6 +1399,16 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code
 		case BPF_JMP | BPF_CALL:
 			ctx->seen |= SEEN_FUNC;
 
+			if (insn[i].src_reg == BPF_REG_0) {
+				if (imm == BPF_FUNC_get_smp_processor_id) {
+					EMIT(PPC_RAW_LHZ(insn[i].src_reg, _R13, offsetof(struct paca_struct, paca_index)));
+					break;
+				} else if (imm == BPF_FUNC_get_current_task) {
+					EMIT(PPC_RAW_LD(insn[i].src_reg, _R13, offsetof(struct paca_struct, __current)));
+					break;
+				}
+			}
+
 			ret = bpf_jit_get_func_addr(fp, &insn[i], extra_pass,
 						    &func_addr, &func_addr_fixed);
 			if (ret < 0)