From patchwork Wed Apr 18 22:56:00 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin KaFai Lau X-Patchwork-Id: 900437 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="H/657r7m"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 40RHYG6pj9z9s15 for ; Thu, 19 Apr 2018 08:56:34 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752899AbeDRW4Z (ORCPT ); Wed, 18 Apr 2018 18:56:25 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:33798 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752846AbeDRW4X (ORCPT ); Wed, 18 Apr 2018 18:56:23 -0400 Received: from pps.filterd (m0001255.ppops.net [127.0.0.1]) by mx0b-00082601.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w3IMWLsh010018 for ; Wed, 18 Apr 2018 15:56:23 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=RwCmgB4yZruXl7OR2Ii2qdkM9vpfplLZfMH6F7PXh/U=; b=H/657r7mNK8Gq7xG0oQvvfc8HR2a8Vxs+yVecmHnsDpOlTa+h6PVxBn9iVc05e3MLOyw bky40wn7cjwGIGTS5/iDPxsGPfD1FBP/6qGEHmgWNTMVIN2m50P+wb98OiLWTxaTD93c rAVc3cF6CsjM44fMAmi7u8lu+SzvuTFSl9s= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0b-00082601.pphosted.com with ESMTP id 2hebaermx0-3 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Wed, 18 Apr 2018 15:56:23 -0700 Received: from mx-out.facebook.com (192.168.52.123) by PRN-CHUB05.TheFacebook.com (192.168.16.15) with Microsoft SMTP Server id 14.3.361.1; Wed, 18 Apr 2018 15:56:12 -0700 Received: by devbig738.prn1.facebook.com (Postfix, from userid 6611) id 0F6CF45009BB; Wed, 18 Apr 2018 15:56:06 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Martin KaFai Lau Smtp-Origin-Hostname: devbig738.prn1.facebook.com To: CC: Alexei Starovoitov , Daniel Borkmann , Smtp-Origin-Cluster: prn1c29 Subject: [PATCH bpf-next v5 04/10] bpf: btf: Add pretty print capability for data with BTF type info Date: Wed, 18 Apr 2018 15:56:00 -0700 Message-ID: <20180418225606.2771620-5-kafai@fb.com> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20180418225606.2771620-1-kafai@fb.com> References: <20180418225606.2771620-1-kafai@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-04-18_05:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch adds pretty print capability for data with BTF type info. The current usage is to allow pretty print for a BPF map. The next few patches will allow a read() on a pinned map with BTF type info for its key and value. This patch uses the seq_printf() infra. Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov --- include/linux/btf.h | 2 + kernel/bpf/btf.c | 198 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 200 insertions(+) diff --git a/include/linux/btf.h b/include/linux/btf.h index f14b60368753..d8bdab0280ba 100644 --- a/include/linux/btf.h +++ b/include/linux/btf.h @@ -33,5 +33,7 @@ struct btf_type; const struct btf_type *btf_type_id_size(const struct btf *btf, u32 *type_id, u32 *ret_size); +void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, + struct seq_file *m); #endif diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 4e31249f6c61..10ee41589da2 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3,6 +3,7 @@ #include #include +#include #include #include #include @@ -256,6 +257,9 @@ struct btf_kind_operations { const struct btf_type *member_type); void (*log_details)(struct btf_verifier_env *env, const struct btf_type *t); + void (*seq_show)(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offsets, + struct seq_file *m); }; static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS]; @@ -781,6 +785,13 @@ static int btf_df_resolve(struct btf_verifier_env *env, return -EINVAL; } +static void btf_df_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offsets, + struct seq_file *m) +{ + seq_printf(m, "", BTF_INFO_KIND(t->info)); +} + static int btf_int_check_member(struct btf_verifier_env *env, const struct btf_type *struct_type, const struct btf_member *member, @@ -879,11 +890,96 @@ static void btf_int_log(struct btf_verifier_env *env, btf_int_encoding_str(BTF_INT_ENCODING(int_data))); } +static void btf_int_bits_seq_show(const struct btf *btf, + const struct btf_type *t, + void *data, u8 bits_offset, + struct seq_file *m) +{ + u32 int_data = btf_type_int(t); + u16 nr_bits = BTF_INT_BITS(int_data); + u16 total_bits_offset; + u16 nr_copy_bytes; + u16 nr_copy_bits; + u8 nr_upper_bits; + union { + u64 u64_num; + u8 u8_nums[8]; + } print_num; + + total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); + data += BITS_ROUNDDOWN_BYTES(total_bits_offset); + bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); + nr_copy_bits = nr_bits + bits_offset; + nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); + + print_num.u64_num = 0; + memcpy(&print_num.u64_num, data, nr_copy_bytes); + + /* Ditch the higher order bits */ + nr_upper_bits = BITS_PER_BYTE_MASKED(nr_copy_bits); + if (nr_upper_bits) { + /* We need to mask out some bits of the upper byte. */ + u8 mask = (1 << nr_upper_bits) - 1; + + print_num.u8_nums[nr_copy_bytes - 1] &= mask; + } + + print_num.u64_num >>= bits_offset; + + seq_printf(m, "0x%llx", print_num.u64_num); +} + +static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offset, + struct seq_file *m) +{ + u32 int_data = btf_type_int(t); + u8 encoding = BTF_INT_ENCODING(int_data); + bool sign = encoding & BTF_INT_SIGNED; + u32 nr_bits = BTF_INT_BITS(int_data); + + if (bits_offset || BTF_INT_OFFSET(int_data) || + BITS_PER_BYTE_MASKED(nr_bits)) { + btf_int_bits_seq_show(btf, t, data, bits_offset, m); + return; + } + + switch (nr_bits) { + case 64: + if (sign) + seq_printf(m, "%lld", *(s64 *)data); + else + seq_printf(m, "%llu", *(u64 *)data); + break; + case 32: + if (sign) + seq_printf(m, "%d", *(s32 *)data); + else + seq_printf(m, "%u", *(u32 *)data); + break; + case 16: + if (sign) + seq_printf(m, "%d", *(s16 *)data); + else + seq_printf(m, "%u", *(u16 *)data); + break; + case 8: + if (sign) + seq_printf(m, "%d", *(s8 *)data); + else + seq_printf(m, "%u", *(u8 *)data); + break; + default: + btf_int_bits_seq_show(btf, t, data, bits_offset, m); + } +} + static const struct btf_kind_operations int_ops = { .check_meta = btf_int_check_meta, .resolve = btf_df_resolve, .check_member = btf_int_check_member, .log_details = btf_int_log, + .seq_show = btf_int_seq_show, }; static int btf_modifier_check_member(struct btf_verifier_env *env, @@ -1054,6 +1150,24 @@ static int btf_ptr_resolve(struct btf_verifier_env *env, return 0; } +static void btf_modifier_seq_show(const struct btf *btf, + const struct btf_type *t, + u32 type_id, void *data, + u8 bits_offset, struct seq_file *m) +{ + t = btf_type_id_resolve(btf, &type_id); + + btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m); +} + +static void btf_ptr_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offset, + struct seq_file *m) +{ + /* It is a hashed value */ + seq_printf(m, "%p", *(void **)data); +} + static void btf_ref_type_log(struct btf_verifier_env *env, const struct btf_type *t) { @@ -1065,6 +1179,7 @@ static struct btf_kind_operations modifier_ops = { .resolve = btf_modifier_resolve, .check_member = btf_modifier_check_member, .log_details = btf_ref_type_log, + .seq_show = btf_modifier_seq_show, }; static struct btf_kind_operations ptr_ops = { @@ -1072,6 +1187,7 @@ static struct btf_kind_operations ptr_ops = { .resolve = btf_ptr_resolve, .check_member = btf_ptr_check_member, .log_details = btf_ref_type_log, + .seq_show = btf_ptr_seq_show, }; static struct btf_kind_operations fwd_ops = { @@ -1079,6 +1195,7 @@ static struct btf_kind_operations fwd_ops = { .resolve = btf_df_resolve, .check_member = btf_df_check_member, .log_details = btf_ref_type_log, + .seq_show = btf_df_seq_show, }; static int btf_array_check_member(struct btf_verifier_env *env, @@ -1209,11 +1326,36 @@ static void btf_array_log(struct btf_verifier_env *env, array->type, array->index_type, array->nelems); } +static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offset, + struct seq_file *m) +{ + const struct btf_array *array = btf_type_array(t); + const struct btf_kind_operations *elem_ops; + const struct btf_type *elem_type; + u32 i, elem_size, elem_type_id; + + elem_type_id = array->type; + elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size); + elem_ops = btf_type_ops(elem_type); + seq_puts(m, "["); + for (i = 0; i < array->nelems; i++) { + if (i) + seq_puts(m, ","); + + elem_ops->seq_show(btf, elem_type, elem_type_id, data, + bits_offset, m); + data += elem_size; + } + seq_puts(m, "]"); +} + static struct btf_kind_operations array_ops = { .check_meta = btf_array_check_meta, .resolve = btf_array_resolve, .check_member = btf_array_check_member, .log_details = btf_array_log, + .seq_show = btf_array_seq_show, }; static int btf_struct_check_member(struct btf_verifier_env *env, @@ -1361,11 +1503,39 @@ static void btf_struct_log(struct btf_verifier_env *env, btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); } +static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offset, + struct seq_file *m) +{ + const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ","; + const struct btf_member *member; + u32 i; + + seq_puts(m, "{"); + for_each_member(i, t, member) { + const struct btf_type *member_type = btf_type_by_id(btf, + member->type); + u32 member_offset = member->offset; + u32 bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); + u8 bits8_offset = BITS_PER_BYTE_MASKED(member_offset); + const struct btf_kind_operations *ops; + + if (i) + seq_puts(m, seq); + + ops = btf_type_ops(member_type); + ops->seq_show(btf, member_type, member->type, + data + bytes_offset, bits8_offset, m); + } + seq_puts(m, "}"); +} + static struct btf_kind_operations struct_ops = { .check_meta = btf_struct_check_meta, .resolve = btf_struct_resolve, .check_member = btf_struct_check_member, .log_details = btf_struct_log, + .seq_show = btf_struct_seq_show, }; static int btf_enum_check_member(struct btf_verifier_env *env, @@ -1441,11 +1611,31 @@ static void btf_enum_log(struct btf_verifier_env *env, btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); } +static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t, + u32 type_id, void *data, u8 bits_offset, + struct seq_file *m) +{ + const struct btf_enum *enums = btf_type_enum(t); + u32 i, nr_enums = btf_type_vlen(t); + int v = *(int *)data; + + for (i = 0; i < nr_enums; i++) { + if (v == enums[i].val) { + seq_printf(m, "%s", + btf_name_by_offset(btf, enums[i].name)); + return; + } + } + + seq_printf(m, "%d", v); +} + static struct btf_kind_operations enum_ops = { .check_meta = btf_enum_check_meta, .resolve = btf_df_resolve, .check_member = btf_enum_check_member, .log_details = btf_enum_log, + .seq_show = btf_enum_seq_show, }; static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { @@ -1782,3 +1972,11 @@ static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size, btf_free(btf); return ERR_PTR(err); } + +void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj, + struct seq_file *m) +{ + const struct btf_type *t = btf_type_by_id(btf, type_id); + + btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m); +}