s390/bpf: Implement unconditional byte swap

iii-i · Alexei Starovoitov · commit 90f426d35e01 · 2023-09-21T14:22:00.000-07:00
Implement the cpuv4 unconditional byte swap, which is encoded as BPF_ALU64 | BPF_END | BPF_FROM_LE. Since s390x is big-endian, it's the same as the existing BPF_ALU | BPF_END | BPF_FROM_LE. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/20230919101336.2223655-7-iii@linux.ibm.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
@@ -1253,6 +1253,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
 		}
 		break;
 	case BPF_ALU | BPF_END | BPF_FROM_LE:
+	case BPF_ALU64 | BPF_END | BPF_FROM_LE:
 		switch (imm) {
 		case 16: /* dst = (u16) cpu_to_le16(dst) */
 			/* lrvr %dst,%dst */

Original file line number	Diff line number	Diff line change
`@@ -1253,6 +1253,7 @@ static noinline int bpf_jit_insn(struct bpf_jit jit, struct bpf_prog fp,`
`1253`	`1253`	`}`
`1254`	`1254`	`break;`
`1255`	`1255`	`case BPF_ALU \| BPF_END \| BPF_FROM_LE:`
	`1256`	`+ case BPF_ALU64 \| BPF_END \| BPF_FROM_LE:`
`1256`	`1257`	`switch (imm) {`
`1257`	`1258`	`case 16: /* dst = (u16) cpu_to_le16(dst) */`
`1258`	`1259`	`/* lrvr %dst,%dst */`