From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jakub Kicinski Subject: [PATCH bpf-next v3 7/9] bpf: offload: report device information for offloaded programs Date: Wed, 27 Dec 2017 18:39:09 -0800 Message-ID: <20171228023911.4251-8-jakub.kicinski@netronome.com> References: <20171228023911.4251-1-jakub.kicinski@netronome.com> Cc: oss-drivers@netronome.com, Jakub Kicinski , "Eric W . Biederman" To: netdev@vger.kernel.org, daniel@iogearbox.net, alexei.starovoitov@gmail.com Return-path: Received: from mail-pf0-f193.google.com ([209.85.192.193]:39112 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753172AbdL1Cj5 (ORCPT ); Wed, 27 Dec 2017 21:39:57 -0500 Received: by mail-pf0-f193.google.com with SMTP id l24so20461319pfj.6 for ; Wed, 27 Dec 2017 18:39:57 -0800 (PST) In-Reply-To: <20171228023911.4251-1-jakub.kicinski@netronome.com> Sender: netdev-owner@vger.kernel.org List-ID: Report to the user ifindex and namespace information of offloaded programs. If device has disappeared return -ENODEV. Specify the namespace using dev/inode combination. CC: Eric W. Biederman Signed-off-by: Jakub Kicinski --- v3: - path_put() (Daniel); - move more of the logic to nsfs.c (Daniel). v2: - take RTNL lock to grab a coherent snapshot of device state (ifindex vs name space) and avoid races with name space moves (based on Eric's comment on Kirill's patch to peernet2id_alloc()). --- include/linux/bpf.h | 2 ++ include/uapi/linux/bpf.h | 3 +++ kernel/bpf/offload.c | 59 ++++++++++++++++++++++++++++++++++++++++++ kernel/bpf/syscall.c | 6 +++++ tools/include/uapi/linux/bpf.h | 3 +++ 5 files changed, 73 insertions(+) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 9a916ab34299..7810ae57b357 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -531,6 +531,8 @@ static inline struct bpf_prog *bpf_prog_get_type(u32 ufd, int bpf_prog_offload_compile(struct bpf_prog *prog); void bpf_prog_offload_destroy(struct bpf_prog *prog); +int bpf_prog_offload_info_fill(struct bpf_prog_info *info, + struct bpf_prog *prog); #if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL) int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d01f1cb3cfc0..72b37fc3bc0c 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -921,6 +921,9 @@ struct bpf_prog_info { __u32 nr_map_ids; __aligned_u64 map_ids; char name[BPF_OBJ_NAME_LEN]; + __u32 ifindex; + __u64 netns_dev; + __u64 netns_ino; } __attribute__((aligned(8))); struct bpf_map_info { diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index e4f1668a021c..040d4e0edf3f 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -16,9 +16,11 @@ #include #include #include +#include #include #include #include +#include #include #include @@ -176,6 +178,63 @@ int bpf_prog_offload_compile(struct bpf_prog *prog) return bpf_prog_offload_translate(prog); } +struct ns_get_path_bpf_prog_args { + struct bpf_prog *prog; + struct bpf_prog_info *info; +}; + +static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) +{ + struct ns_get_path_bpf_prog_args *args = private_data; + struct bpf_prog_aux *aux = args->prog->aux; + struct ns_common *ns; + struct net *net; + + rtnl_lock(); + down_read(&bpf_devs_lock); + + if (aux->offload) { + args->info->ifindex = aux->offload->netdev->ifindex; + net = dev_net(aux->offload->netdev); + get_net(net); + ns = &net->ns; + } else { + args->info->ifindex = 0; + ns = NULL; + } + + up_read(&bpf_devs_lock); + rtnl_unlock(); + + return ns; +} + +int bpf_prog_offload_info_fill(struct bpf_prog_info *info, + struct bpf_prog *prog) +{ + struct ns_get_path_bpf_prog_args args = { + .prog = prog, + .info = info, + }; + struct inode *ns_inode; + struct path ns_path; + void *res; + + res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); + if (IS_ERR(res)) { + if (!info->ifindex) + return -ENODEV; + return PTR_ERR(res); + } + + ns_inode = ns_path.dentry->d_inode; + info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); + info->netns_ino = ns_inode->i_ino; + path_put(&ns_path); + + return 0; +} + const struct bpf_prog_ops bpf_offload_prog_ops = { }; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7d9f5b0f0e49..20444fd678d0 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1624,6 +1624,12 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, return -EFAULT; } + if (bpf_prog_is_dev_bound(prog->aux)) { + err = bpf_prog_offload_info_fill(&info, prog); + if (err) + return err; + } + done: if (copy_to_user(uinfo, &info, info_len) || put_user(info_len, &uattr->info.info_len)) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index db1b0923a308..4e8c60acfa32 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -921,6 +921,9 @@ struct bpf_prog_info { __u32 nr_map_ids; __aligned_u64 map_ids; char name[BPF_OBJ_NAME_LEN]; + __u32 ifindex; + __u64 netns_dev; + __u64 netns_ino; } __attribute__((aligned(8))); struct bpf_map_info { -- 2.15.1