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| author | Zi Shen Lim <zlim.lnx@gmail.com> | 2014-09-16 22:29:23 +0200 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2014-10-20 18:47:03 +0200 |
| commit | 30d3d94cc3d507a23dcb09e5c365464e4aa9f580 (patch) | |
| tree | 61915f1797c20cb0c0cca32d97cf81d1734298a5 | |
| parent | arm64: bpf: add 'shift by register' instructions (diff) | |
| download | linux-30d3d94cc3d507a23dcb09e5c365464e4aa9f580.tar.xz linux-30d3d94cc3d507a23dcb09e5c365464e4aa9f580.zip | |
arm64: bpf: add 'load 64-bit immediate' instruction
Commit 02ab695bb37e (net: filter: add "load 64-bit immediate" eBPF
instruction) introduced a new eBPF instruction. Let's add support
for this for arm64 as well.
Our arm64 eBPF JIT compiler now passes the new "load 64-bit
immediate" test case introduced in the same commit 02ab695bb37e.
Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 80cc76972798..618d2cdc2f1b 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -205,6 +205,12 @@ static void build_epilogue(struct jit_ctx *ctx) emit(A64_RET(A64_LR), ctx); } +/* JITs an eBPF instruction. + * Returns: + * 0 - successfully JITed an 8-byte eBPF instruction. + * >0 - successfully JITed a 16-byte eBPF instruction. + * <0 - failed to JIT. + */ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) { const u8 code = insn->code; @@ -464,6 +470,27 @@ emit_cond_jmp: emit(A64_B(jmp_offset), ctx); break; + /* dst = imm64 */ + case BPF_LD | BPF_IMM | BPF_DW: + { + const struct bpf_insn insn1 = insn[1]; + u64 imm64; + + if (insn1.code != 0 || insn1.src_reg != 0 || + insn1.dst_reg != 0 || insn1.off != 0) { + /* Note: verifier in BPF core must catch invalid + * instructions. + */ + pr_err_once("Invalid BPF_LD_IMM64 instruction\n"); + return -EINVAL; + } + + imm64 = (u64)insn1.imm << 32 | imm; + emit_a64_mov_i64(dst, imm64, ctx); + + return 1; + } + /* LDX: dst = *(size *)(src + off) */ case BPF_LDX | BPF_MEM | BPF_W: case BPF_LDX | BPF_MEM | BPF_H: @@ -615,6 +642,10 @@ static int build_body(struct jit_ctx *ctx) ctx->offset[i] = ctx->idx; ret = build_insn(insn, ctx); + if (ret > 0) { + i++; + continue; + } if (ret) return ret; } |