From patchwork Fri Jun 21 23:16:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Vazquez X-Patchwork-Id: 1120536 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=reject dis=none) header.from=google.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="B9Z3H8QT"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45Vvhw1CPkz9sBp for ; Sat, 22 Jun 2019 09:17:04 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726148AbfFUXRC (ORCPT ); Fri, 21 Jun 2019 19:17:02 -0400 Received: from mail-pl1-f202.google.com ([209.85.214.202]:47010 "EHLO mail-pl1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726058AbfFUXRA (ORCPT ); Fri, 21 Jun 2019 19:17:00 -0400 Received: by mail-pl1-f202.google.com with SMTP id e7so4422505plt.13 for ; Fri, 21 Jun 2019 16:17:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=t/AyvcKYelZOkRBej05NHVNdPUqzSYdpnSoVrXwFeq8=; b=B9Z3H8QTIhgljGVr21xxKuCQSAUteNzuLnIR45pj/KSavVYu52KUe4EWiL+820PeIA 1eiH126tYB7qw608tdE5kY3eI5zRmST/YSgm4d/c3YdK1M2olH91FofinMNIIDadRGNg gAMbqzKlLkdr6Uge2EXPpRMBz0Wk+gF20YOWGGGUb1ZDV2fVCuzr9naZCqorcIilwkAt cBdORtrxwPwBQu0AyoS3TY2SP7xnJdWKNB2Y/TB8QFKgz0jNto7uOiMQ7ozcLCKxY+Cf YoMw3tgrihHmO1nA/M0E63tM2JESnkITwBbVQ1j8zrt4IpygjwOv2TdZr/hkrChN1GcO IZeA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=t/AyvcKYelZOkRBej05NHVNdPUqzSYdpnSoVrXwFeq8=; b=dpJYghEGpgoV4862qNi9+DZNo0a+NRouCmwX/xaFpPTbZZJr+vARpEUzvjyzKg9Qx4 qj2H9AbAXjQxX0tyGQxfPSlSs2Ym7zaU2yDFtDPNJZEimN0Ex0ZjzyMbUHmCmcJlstVV 5AbH9l54FXiHZPWHx57jEMqNeGEjAgHzdEBLn8HlmP4uN5i6EyNleMg4Fg6Fi2Ko0UPl MYvBqM127/N7NdiQIP4mgVPNqPJoakMVQjrzbPcEBiCX1QiTeAoir3ru3wtnpZTX592i wWTvJFgVhgLqMCOFzHECSfCu/ejHPBdy77ThMPeFVwxSSpg8Udsmxt93U515KJ5z9lQX Tyxw== X-Gm-Message-State: APjAAAUiAukP7XYguioegUJ31CtcAGtAcLg/GpUbWzOXZPkSBQfN6S52 Sg08uaolLU+5mDfCXOewnb6ULR1RvOuS X-Google-Smtp-Source: APXvYqzlq6hsSVc/T2F+nA1QdHOIWXppI7xnktxRsvwQKhadXg35L+WlMBX2eh3IOkqD8n6fwdypPYZa4bkL X-Received: by 2002:a63:6cc3:: with SMTP id h186mr864592pgc.292.1561159019516; Fri, 21 Jun 2019 16:16:59 -0700 (PDT) Date: Fri, 21 Jun 2019 16:16:45 -0700 In-Reply-To: <20190621231650.32073-1-brianvv@google.com> Message-Id: <20190621231650.32073-2-brianvv@google.com> Mime-Version: 1.0 References: <20190621231650.32073-1-brianvv@google.com> X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog Subject: [RFC PATCH 1/6] bpf: add bpf_map_value_size and bp_map_copy_value helper functions From: Brian Vazquez To: Brian Vazquez , Alexei Starovoitov , Daniel Borkmann , "David S . Miller" Cc: Stanislav Fomichev , Willem de Bruijn , Petar Penkov , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, Brian Vazquez Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Move reusable code from map_lookup_elem to helper functions to avoid code duplication in kernel/bpf/syscall.c Suggested-by: Stanislav Fomichev Signed-off-by: Brian Vazquez --- kernel/bpf/syscall.c | 134 +++++++++++++++++++++++-------------------- 1 file changed, 73 insertions(+), 61 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7713cf39795a4..a1823a50f9be0 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -126,6 +126,76 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) return map; } +static u32 bpf_map_value_size(struct bpf_map *map) +{ + if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || + map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) + return round_up(map->value_size, 8) * num_possible_cpus(); + else if (IS_FD_MAP(map)) + return sizeof(u32); + else + return map->value_size; +} + +static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value, + __u64 flags) +{ + void *ptr; + int err; + + if (bpf_map_is_dev_bound(map)) + return bpf_map_offload_lookup_elem(map, key, value); + + preempt_disable(); + this_cpu_inc(bpf_prog_active); + if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + err = bpf_percpu_hash_copy(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { + err = bpf_percpu_array_copy(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { + err = bpf_percpu_cgroup_storage_copy(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { + err = bpf_stackmap_copy(map, key, value); + } else if (IS_FD_ARRAY(map)) { + err = bpf_fd_array_map_lookup_elem(map, key, value); + } else if (IS_FD_HASH(map)) { + err = bpf_fd_htab_map_lookup_elem(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { + err = bpf_fd_reuseport_array_lookup_elem(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_QUEUE || + map->map_type == BPF_MAP_TYPE_STACK) { + err = map->ops->map_peek_elem(map, value); + } else { + rcu_read_lock(); + if (map->ops->map_lookup_elem_sys_only) + ptr = map->ops->map_lookup_elem_sys_only(map, key); + else + ptr = map->ops->map_lookup_elem(map, key); + if (IS_ERR(ptr)) { + err = PTR_ERR(ptr); + } else if (!ptr) { + err = -ENOENT; + } else { + err = 0; + if (flags & BPF_F_LOCK) + /* lock 'ptr' and copy everything but lock */ + copy_map_value_locked(map, value, ptr, true); + else + copy_map_value(map, value, ptr); + /* mask lock, since value wasn't zero inited */ + check_and_init_map_lock(map, value); + } + rcu_read_unlock(); + } + this_cpu_dec(bpf_prog_active); + preempt_enable(); + + return err; +} + void *bpf_map_area_alloc(size_t size, int numa_node) { /* We really just want to fail instead of triggering OOM killer @@ -729,7 +799,7 @@ static int map_lookup_elem(union bpf_attr *attr) void __user *uvalue = u64_to_user_ptr(attr->value); int ufd = attr->map_fd; struct bpf_map *map; - void *key, *value, *ptr; + void *key, *value; u32 value_size; struct fd f; int err; @@ -761,72 +831,14 @@ static int map_lookup_elem(union bpf_attr *attr) goto err_put; } - if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY || - map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) - value_size = round_up(map->value_size, 8) * num_possible_cpus(); - else if (IS_FD_MAP(map)) - value_size = sizeof(u32); - else - value_size = map->value_size; + value_size = bpf_map_value_size(map); err = -ENOMEM; value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); if (!value) goto free_key; - if (bpf_map_is_dev_bound(map)) { - err = bpf_map_offload_lookup_elem(map, key, value); - goto done; - } - - preempt_disable(); - this_cpu_inc(bpf_prog_active); - if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { - err = bpf_percpu_hash_copy(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { - err = bpf_percpu_array_copy(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) { - err = bpf_percpu_cgroup_storage_copy(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { - err = bpf_stackmap_copy(map, key, value); - } else if (IS_FD_ARRAY(map)) { - err = bpf_fd_array_map_lookup_elem(map, key, value); - } else if (IS_FD_HASH(map)) { - err = bpf_fd_htab_map_lookup_elem(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) { - err = bpf_fd_reuseport_array_lookup_elem(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_QUEUE || - map->map_type == BPF_MAP_TYPE_STACK) { - err = map->ops->map_peek_elem(map, value); - } else { - rcu_read_lock(); - if (map->ops->map_lookup_elem_sys_only) - ptr = map->ops->map_lookup_elem_sys_only(map, key); - else - ptr = map->ops->map_lookup_elem(map, key); - if (IS_ERR(ptr)) { - err = PTR_ERR(ptr); - } else if (!ptr) { - err = -ENOENT; - } else { - err = 0; - if (attr->flags & BPF_F_LOCK) - /* lock 'ptr' and copy everything but lock */ - copy_map_value_locked(map, value, ptr, true); - else - copy_map_value(map, value, ptr); - /* mask lock, since value wasn't zero inited */ - check_and_init_map_lock(map, value); - } - rcu_read_unlock(); - } - this_cpu_dec(bpf_prog_active); - preempt_enable(); - -done: + err = bpf_map_copy_value(map, key, value, attr->flags); if (err) goto free_value;