diff options
Diffstat (limited to 'arch/arm64/net/bpf_jit_comp.c')
-rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 49 |
1 files changed, 33 insertions, 16 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index a6fdaea07c63..1542df00b23c 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -134,10 +134,9 @@ static inline void emit_a64_mov_i64(const int reg, const u64 val, } /* - * This is an unoptimized 64 immediate emission used for BPF to BPF call - * addresses. It will always do a full 64 bit decomposition as otherwise - * more complexity in the last extra pass is required since we previously - * reserved 4 instructions for the address. + * Kernel addresses in the vmalloc space use at most 48 bits, and the + * remaining bits are guaranteed to be 0x1. So we can compose the address + * with a fixed length movn/movk/movk sequence. */ static inline void emit_addr_mov_i64(const int reg, const u64 val, struct jit_ctx *ctx) @@ -145,8 +144,8 @@ static inline void emit_addr_mov_i64(const int reg, const u64 val, u64 tmp = val; int shift = 0; - emit(A64_MOVZ(1, reg, tmp & 0xffff, shift), ctx); - for (;shift < 48;) { + emit(A64_MOVN(1, reg, ~tmp & 0xffff, shift), ctx); + while (shift < 32) { tmp >>= 16; shift += 16; emit(A64_MOVK(1, reg, tmp & 0xffff, shift), ctx); @@ -351,7 +350,8 @@ static void build_epilogue(struct jit_ctx *ctx) * >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) +static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, + bool extra_pass) { const u8 code = insn->code; const u8 dst = bpf2a64[insn->dst_reg]; @@ -625,12 +625,15 @@ emit_cond_jmp: case BPF_JMP | BPF_CALL: { const u8 r0 = bpf2a64[BPF_REG_0]; - const u64 func = (u64)__bpf_call_base + imm; + bool func_addr_fixed; + u64 func_addr; + int ret; - if (ctx->prog->is_func) - emit_addr_mov_i64(tmp, func, ctx); - else - emit_a64_mov_i64(tmp, func, ctx); + ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass, + &func_addr, &func_addr_fixed); + if (ret < 0) + return ret; + emit_addr_mov_i64(tmp, func_addr, ctx); emit(A64_BLR(tmp), ctx); emit(A64_MOV(1, r0, A64_R(0)), ctx); break; @@ -753,7 +756,7 @@ emit_cond_jmp: return 0; } -static int build_body(struct jit_ctx *ctx) +static int build_body(struct jit_ctx *ctx, bool extra_pass) { const struct bpf_prog *prog = ctx->prog; int i; @@ -762,7 +765,7 @@ static int build_body(struct jit_ctx *ctx) const struct bpf_insn *insn = &prog->insnsi[i]; int ret; - ret = build_insn(insn, ctx); + ret = build_insn(insn, ctx, extra_pass); if (ret > 0) { i++; if (ctx->image == NULL) @@ -858,7 +861,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) /* 1. Initial fake pass to compute ctx->idx. */ /* Fake pass to fill in ctx->offset. */ - if (build_body(&ctx)) { + if (build_body(&ctx, extra_pass)) { prog = orig_prog; goto out_off; } @@ -888,7 +891,7 @@ skip_init_ctx: build_prologue(&ctx, was_classic); - if (build_body(&ctx)) { + if (build_body(&ctx, extra_pass)) { bpf_jit_binary_free(header); prog = orig_prog; goto out_off; @@ -929,6 +932,7 @@ skip_init_ctx: prog->jited_len = image_size; if (!prog->is_func || extra_pass) { + bpf_prog_fill_jited_linfo(prog, ctx.offset); out_off: kfree(ctx.offset); kfree(jit_data); @@ -940,3 +944,16 @@ out: tmp : orig_prog); return prog; } + +void *bpf_jit_alloc_exec(unsigned long size) +{ + return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START, + BPF_JIT_REGION_END, GFP_KERNEL, + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, + __builtin_return_address(0)); +} + +void bpf_jit_free_exec(void *addr) +{ + return vfree(addr); +} |