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| author | Alexei Starovoitov <ast@fb.com> | 2017-05-30 13:31:27 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-05-31 19:29:47 -0400 |
| commit | 71189fa9b092ef125ee741eccb2f5fa916798afd (patch) | |
| tree | 6a2f3dd82c3332011d215d85d9b56d38502e8864 | |
| parent | d2e0ef493ad953048bdf562b06cc4330b3fd9fb7 (diff) | |
| download | linux-71189fa9b092ef125ee741eccb2f5fa916798afd.tar.gz linux-71189fa9b092ef125ee741eccb2f5fa916798afd.tar.bz2 linux-71189fa9b092ef125ee741eccb2f5fa916798afd.zip | |
bpf: free up BPF_JMP | BPF_CALL | BPF_X opcode
free up BPF_JMP | BPF_CALL | BPF_X opcode to be used by actual
indirect call by register and use kernel internal opcode to
mark call instruction into bpf_tail_call() helper.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 2 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp64.c | 2 | ||||
| -rw-r--r-- | arch/s390/net/bpf_jit_comp.c | 2 | ||||
| -rw-r--r-- | arch/sparc/net/bpf_jit_comp_64.c | 2 | ||||
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 2 | ||||
| -rw-r--r-- | include/linux/filter.h | 3 | ||||
| -rw-r--r-- | kernel/bpf/core.c | 2 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 2 |
8 files changed, 10 insertions, 7 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 71f930501ade..b1d38eeb24f6 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -586,7 +586,7 @@ emit_cond_jmp: break; } /* tail call */ - case BPF_JMP | BPF_CALL | BPF_X: + case BPF_JMP | BPF_TAIL_CALL: if (emit_bpf_tail_call(ctx)) return -EFAULT; break; diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index aee2bb817ac6..a01366584a4b 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -938,7 +938,7 @@ common_load: /* * Tail call */ - case BPF_JMP | BPF_CALL | BPF_X: + case BPF_JMP | BPF_TAIL_CALL: ctx->seen |= SEEN_TAILCALL; bpf_jit_emit_tail_call(image, ctx, addrs[i + 1]); break; diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 6e97a2e3fd8d..42ad3832586c 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -991,7 +991,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i } break; } - case BPF_JMP | BPF_CALL | BPF_X: + case BPF_JMP | BPF_TAIL_CALL: /* * Implicit input: * B1: pointer to ctx diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c index 21de77419f48..4a52d34facf9 100644 --- a/arch/sparc/net/bpf_jit_comp_64.c +++ b/arch/sparc/net/bpf_jit_comp_64.c @@ -1217,7 +1217,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) } /* tail call */ - case BPF_JMP | BPF_CALL |BPF_X: + case BPF_JMP | BPF_TAIL_CALL: emit_tail_call(ctx); break; diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index f58939393eef..fec12eaa0dec 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -877,7 +877,7 @@ xadd: if (is_imm8(insn->off)) } break; - case BPF_JMP | BPF_CALL | BPF_X: + case BPF_JMP | BPF_TAIL_CALL: emit_bpf_tail_call(&prog); break; diff --git a/include/linux/filter.h b/include/linux/filter.h index 62d948f80730..a20ba40fcb73 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -57,6 +57,9 @@ struct bpf_prog_aux; #define BPF_REG_AX MAX_BPF_REG #define MAX_BPF_JIT_REG (MAX_BPF_REG + 1) +/* unused opcode to mark special call to bpf_tail_call() helper */ +#define BPF_TAIL_CALL 0xf0 + /* As per nm, we expose JITed images as text (code) section for * kallsyms. That way, tools like perf can find it to match * addresses. diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index dedf367f59bb..339289402b96 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -824,7 +824,7 @@ static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn) [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG, /* Call instruction */ [BPF_JMP | BPF_CALL] = &&JMP_CALL, - [BPF_JMP | BPF_CALL | BPF_X] = &&JMP_TAIL_CALL, + [BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL, /* Jumps */ [BPF_JMP | BPF_JA] = &&JMP_JA, [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 339c8a1371de..28113d0e8e92 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3469,7 +3469,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) * that doesn't support bpf_tail_call yet */ insn->imm = 0; - insn->code |= BPF_X; + insn->code = BPF_JMP | BPF_TAIL_CALL; continue; } |