From patchwork Mon May 4 06:25:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 220006 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5675C47257 for ; Mon, 4 May 2020 06:26:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C109920735 for ; Mon, 4 May 2020 06:26:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="Qj4I29xc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727951AbgEDG0L (ORCPT ); Mon, 4 May 2020 02:26:11 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:48454 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727896AbgEDG0H (ORCPT ); Mon, 4 May 2020 02:26:07 -0400 Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 04469Bom020395 for ; Sun, 3 May 2020 23:26:06 -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-transfer-encoding : content-type; s=facebook; bh=ass9DmuVi3/7YhUJWDPjDknow+B7lQh7i0AOqyYv10o=; b=Qj4I29xcNtKyORLakuI6PJvqef9jt+lSvOfyqQaowdnIdXX1NbxA8dlYECOeaGhaejLI Y6RZaZhJp35mrtQaY2EpfyJAx17PnyO7m3wnE2cgeUFwheY9U4aQsmpK1y/tt31gcuIx aKhsZDhKS/ZGT9iKJcP6wjvaYG3EhPnuRRk= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 30s6cmeqw8-9 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Sun, 03 May 2020 23:26:05 -0700 Received: from intmgw001.08.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1847.3; Sun, 3 May 2020 23:26:02 -0700 Received: by devbig003.ftw2.facebook.com (Postfix, from userid 128203) id 419CF3702037; Sun, 3 May 2020 23:25:57 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Yonghong Song Smtp-Origin-Hostname: devbig003.ftw2.facebook.com To: Andrii Nakryiko , , Martin KaFai Lau , CC: Alexei Starovoitov , Daniel Borkmann , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next v2 09/20] bpf: add bpf_map iterator Date: Sun, 3 May 2020 23:25:57 -0700 Message-ID: <20200504062557.2048107-1-yhs@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200504062547.2047304-1-yhs@fb.com> References: <20200504062547.2047304-1-yhs@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-05-04_02:2020-05-01,2020-05-04 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 adultscore=0 mlxlogscore=999 spamscore=0 suspectscore=0 clxscore=1015 priorityscore=1501 impostorscore=0 lowpriorityscore=0 phishscore=0 mlxscore=0 bulkscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005040054 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Implement seq_file operations to traverse all maps. Signed-off-by: Yonghong Song --- include/linux/bpf.h | 1 + kernel/bpf/Makefile | 2 +- kernel/bpf/map_iter.c | 107 ++++++++++++++++++++++++++++++++++++++++++ kernel/bpf/syscall.c | 19 ++++++++ 4 files changed, 128 insertions(+), 1 deletion(-) create mode 100644 kernel/bpf/map_iter.c diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 70c71c3cd9e8..56b2ded9c2a6 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1082,6 +1082,7 @@ int generic_map_update_batch(struct bpf_map *map, int generic_map_delete_batch(struct bpf_map *map, const union bpf_attr *attr, union bpf_attr __user *uattr); +struct bpf_map *bpf_map_get_curr_or_next(u32 *id); extern int sysctl_unprivileged_bpf_disabled; diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 6a8b0febd3f6..b2b5eefc5254 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -2,7 +2,7 @@ obj-y := core.o CFLAGS_core.o += $(call cc-disable-warning, override-init) -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c new file mode 100644 index 000000000000..fa16a4984326 --- /dev/null +++ b/kernel/bpf/map_iter.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2020 Facebook */ +#include +#include +#include +#include + +struct bpf_iter_seq_map_info { + struct bpf_map *map; + u32 id; +}; + +static void *bpf_map_seq_start(struct seq_file *seq, loff_t *pos) +{ + struct bpf_iter_seq_map_info *info = seq->private; + struct bpf_map *map; + u32 id = info->id; + + map = bpf_map_get_curr_or_next(&id); + if (!map) + return NULL; + + ++*pos; + info->map = map; + info->id = id; + return map; +} + +static void *bpf_map_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct bpf_iter_seq_map_info *info = seq->private; + struct bpf_map *map; + + ++*pos; + ++info->id; + map = bpf_map_get_curr_or_next(&info->id); + if (!map) + return NULL; + + bpf_map_put(info->map); + info->map = map; + return map; +} + +struct bpf_iter__bpf_map { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct bpf_map *, map); +}; + +DEFINE_BPF_ITER_FUNC(bpf_map, struct bpf_iter_meta *meta, struct bpf_map *map) + +static int __bpf_map_seq_show(struct seq_file *seq, void *v, bool in_stop) +{ + struct bpf_iter__bpf_map ctx; + struct bpf_iter_meta meta; + struct bpf_prog *prog; + int ret = 0; + + ctx.meta = &meta; + ctx.map = v; + meta.seq = seq; + prog = bpf_iter_get_info(&meta, in_stop); + if (prog) + ret = bpf_iter_run_prog(prog, &ctx); + + return ret; +} + +static int bpf_map_seq_show(struct seq_file *seq, void *v) +{ + return __bpf_map_seq_show(seq, v, false); +} + +static void bpf_map_seq_stop(struct seq_file *seq, void *v) +{ + struct bpf_iter_seq_map_info *info = seq->private; + + if (!v) + __bpf_map_seq_show(seq, v, true); + + if (info->map) { + bpf_map_put(info->map); + info->map = NULL; + } +} + +static const struct seq_operations bpf_map_seq_ops = { + .start = bpf_map_seq_start, + .next = bpf_map_seq_next, + .stop = bpf_map_seq_stop, + .show = bpf_map_seq_show, +}; + +static int __init bpf_map_iter_init(void) +{ + struct bpf_iter_reg reg_info = { + .target = "bpf_map", + .seq_ops = &bpf_map_seq_ops, + .init_seq_private = NULL, + .fini_seq_private = NULL, + .seq_priv_size = sizeof(struct bpf_iter_seq_map_info), + }; + + return bpf_iter_reg_target(®_info); +} + +late_initcall(bpf_map_iter_init); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index a293e88ee01a..de2a75500233 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2934,6 +2934,25 @@ static int bpf_obj_get_next_id(const union bpf_attr *attr, return err; } +struct bpf_map *bpf_map_get_curr_or_next(u32 *id) +{ + struct bpf_map *map; + + spin_lock_bh(&map_idr_lock); +again: + map = idr_get_next(&map_idr, id); + if (map) { + map = __bpf_map_inc_not_zero(map, false); + if (IS_ERR(map)) { + (*id)++; + goto again; + } + } + spin_unlock_bh(&map_idr_lock); + + return map; +} + #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id struct bpf_prog *bpf_prog_by_id(u32 id)