From: Yonghong Song <yhs@fb•com>
To: Andrii Nakryiko <andriin@fb•com>, <bpf@vger•kernel.org>,
Martin KaFai Lau <kafai@fb•com>, <netdev@vger•kernel.org>
Cc: Alexei Starovoitov <ast@fb•com>,
Daniel Borkmann <daniel@iogearbox•net>, <kernel-team@fb•com>
Subject: [PATCH bpf-next v1 05/19] bpf: support bpf tracing/iter programs for BPF_LINK_CREATE
Date: Mon, 27 Apr 2020 13:12:40 -0700 [thread overview]
Message-ID: <20200427201240.2994985-1-yhs@fb.com> (raw)
In-Reply-To: <20200427201235.2994549-1-yhs@fb.com>
Given a bpf program, the step to create an anonymous bpf iterator is:
- create a bpf_iter_link, which combines bpf program and the target.
In the future, there could be more information recorded in the link.
A link_fd will be returned to the user space.
- create an anonymous bpf iterator with the given link_fd.
The anonymous bpf iterator (and its underlying bpf_link) will be
used to create file based bpf iterator as well.
The benefit to use of bpf_iter_link:
- for file based bpf iterator, bpf_iter_link provides a standard
way to replace underlying bpf programs.
- for both anonymous and free based iterators, bpf link query
capability can be leveraged.
The patch added support of tracing/iter programs for BPF_LINK_CREATE.
Signed-off-by: Yonghong Song <yhs@fb•com>
---
include/linux/bpf.h | 2 ++
kernel/bpf/bpf_iter.c | 54 +++++++++++++++++++++++++++++++++++++++++++
kernel/bpf/syscall.c | 15 ++++++++++++
3 files changed, 71 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 4ac8d61f7c3e..60ecb73d8f6d 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1034,6 +1034,7 @@ extern const struct file_operations bpf_prog_fops;
extern const struct bpf_prog_ops bpf_offload_prog_ops;
extern const struct bpf_verifier_ops tc_cls_act_analyzer_ops;
extern const struct bpf_verifier_ops xdp_analyzer_ops;
+extern const struct bpf_link_ops bpf_iter_link_lops;
struct bpf_prog *bpf_prog_get(u32 ufd);
struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
@@ -1129,6 +1130,7 @@ int bpf_iter_reg_target(struct bpf_iter_reg *reg_info);
struct bpf_prog *bpf_iter_get_prog(struct seq_file *seq, u32 priv_data_size,
u64 *session_id, u64 *seq_num, bool is_last);
int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx);
+int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
index 284c95587803..9532e7bcb8e1 100644
--- a/kernel/bpf/bpf_iter.c
+++ b/kernel/bpf/bpf_iter.c
@@ -14,6 +14,11 @@ struct bpf_iter_target_info {
u32 target_feature;
};
+struct bpf_iter_link {
+ struct bpf_link link;
+ struct bpf_iter_target_info *tinfo;
+};
+
static struct list_head targets;
static struct mutex targets_mutex;
static bool bpf_iter_inited = false;
@@ -67,3 +72,52 @@ int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx)
return ret;
}
+
+static void bpf_iter_link_release(struct bpf_link *link)
+{
+}
+
+static void bpf_iter_link_dealloc(struct bpf_link *link)
+{
+}
+
+const struct bpf_link_ops bpf_iter_link_lops = {
+ .release = bpf_iter_link_release,
+ .dealloc = bpf_iter_link_dealloc,
+};
+
+int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ struct bpf_iter_target_info *tinfo;
+ struct bpf_iter_link *link;
+ const char *func_name;
+ bool existed = false;
+ int err;
+
+ if (attr->link_create.target_fd || attr->link_create.flags)
+ return -EINVAL;
+
+ func_name = prog->aux->attach_func_name;
+ mutex_lock(&targets_mutex);
+ list_for_each_entry(tinfo, &targets, list) {
+ if (!strcmp(tinfo->target_func_name, func_name)) {
+ existed = true;
+ break;
+ }
+ }
+ mutex_unlock(&targets_mutex);
+ if (!existed)
+ return -ENOENT;
+
+ link = kzalloc(sizeof(*link), GFP_USER | __GFP_NOWARN);
+ if (!link)
+ return -ENOMEM;
+
+ bpf_link_init(&link->link, &bpf_iter_link_lops, prog);
+ link->tinfo = tinfo;
+
+ err = bpf_link_new_fd(&link->link);
+ if (err < 0)
+ kfree(link);
+ return err;
+}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 022187640943..8741b5e11c85 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2269,6 +2269,8 @@ static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
else if (link->ops == &bpf_cgroup_link_lops)
link_type = "cgroup";
#endif
+ else if (link->ops == &bpf_iter_link_lops)
+ link_type = "iter";
else
link_type = "unknown";
@@ -2597,6 +2599,8 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_CGROUP_GETSOCKOPT:
case BPF_CGROUP_SETSOCKOPT:
return BPF_PROG_TYPE_CGROUP_SOCKOPT;
+ case BPF_TRACE_ITER:
+ return BPF_PROG_TYPE_TRACING;
default:
return BPF_PROG_TYPE_UNSPEC;
}
@@ -3571,6 +3575,14 @@ static int bpf_map_do_batch(const union bpf_attr *attr,
return err;
}
+static int tracing_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ if (attr->link_create.attach_type == BPF_TRACE_ITER)
+ return bpf_iter_link_attach(attr, prog);
+
+ return -EINVAL;
+}
+
#define BPF_LINK_CREATE_LAST_FIELD link_create.flags
static int link_create(union bpf_attr *attr)
{
@@ -3607,6 +3619,9 @@ static int link_create(union bpf_attr *attr)
case BPF_PROG_TYPE_CGROUP_SOCKOPT:
ret = cgroup_bpf_link_attach(attr, prog);
break;
+ case BPF_PROG_TYPE_TRACING:
+ ret = tracing_bpf_link_attach(attr, prog);
+ break;
default:
ret = -EINVAL;
}
--
2.24.1
next prev parent reply other threads:[~2020-04-27 20:12 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-27 20:12 [PATCH bpf-next v1 00/19] bpf: implement bpf iterator for kernel data Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 01/19] net: refactor net assignment for seq_net_private structure Yonghong Song
2020-04-29 5:38 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 02/19] bpf: implement an interface to register bpf_iter targets Yonghong Song
2020-04-28 16:20 ` Martin KaFai Lau
2020-04-28 16:50 ` Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 03/19] bpf: add bpf_map iterator Yonghong Song
2020-04-29 0:37 ` Martin KaFai Lau
2020-04-29 0:48 ` Alexei Starovoitov
2020-04-29 1:15 ` Yonghong Song
2020-04-29 2:44 ` Alexei Starovoitov
2020-04-29 5:09 ` Yonghong Song
2020-04-29 6:08 ` Andrii Nakryiko
2020-04-29 6:20 ` Yonghong Song
2020-04-29 6:30 ` Alexei Starovoitov
2020-04-29 6:40 ` Andrii Nakryiko
2020-04-29 6:44 ` Yonghong Song
2020-04-29 15:34 ` Alexei Starovoitov
2020-04-29 18:14 ` Yonghong Song
2020-04-29 19:19 ` Andrii Nakryiko
2020-04-29 20:15 ` Yonghong Song
2020-04-30 3:06 ` Alexei Starovoitov
2020-04-30 4:01 ` Yonghong Song
2020-04-29 6:34 ` Martin KaFai Lau
2020-04-29 6:51 ` Yonghong Song
2020-04-29 19:25 ` Andrii Nakryiko
2020-04-29 1:02 ` Yonghong Song
2020-04-29 6:04 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 04/19] bpf: allow loading of a bpf_iter program Yonghong Song
2020-04-29 0:54 ` Martin KaFai Lau
2020-04-29 1:27 ` Yonghong Song
2020-04-27 20:12 ` Yonghong Song [this message]
2020-04-29 1:17 ` [Potential Spoof] [PATCH bpf-next v1 05/19] bpf: support bpf tracing/iter programs for BPF_LINK_CREATE Martin KaFai Lau
2020-04-29 6:25 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 06/19] bpf: support bpf tracing/iter programs for BPF_LINK_UPDATE Yonghong Song
2020-04-29 1:32 ` Martin KaFai Lau
2020-04-29 5:04 ` Yonghong Song
2020-04-29 5:58 ` Martin KaFai Lau
2020-04-29 6:32 ` Andrii Nakryiko
2020-04-29 6:41 ` Martin KaFai Lau
2020-04-27 20:12 ` [PATCH bpf-next v1 07/19] bpf: create anonymous bpf iterator Yonghong Song
2020-04-29 5:39 ` Martin KaFai Lau
2020-04-29 6:56 ` Andrii Nakryiko
2020-04-29 7:06 ` Yonghong Song
2020-04-29 18:16 ` Andrii Nakryiko
2020-04-29 18:46 ` Martin KaFai Lau
2020-04-29 19:20 ` Yonghong Song
2020-04-29 20:50 ` Martin KaFai Lau
2020-04-29 20:54 ` Yonghong Song
2020-04-29 19:39 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 08/19] bpf: create file " Yonghong Song
2020-04-29 20:40 ` Andrii Nakryiko
2020-04-30 18:02 ` Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 09/19] bpf: add PTR_TO_BTF_ID_OR_NULL support Yonghong Song
2020-04-29 20:46 ` Andrii Nakryiko
2020-04-29 20:51 ` Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 10/19] bpf: add netlink and ipv6_route targets Yonghong Song
2020-04-28 19:49 ` kbuild test robot
2020-04-28 19:50 ` [RFC PATCH] bpf: __bpf_iter__netlink() can be static kbuild test robot
2020-04-27 20:12 ` [PATCH bpf-next v1 11/19] bpf: add task and task/file targets Yonghong Song
2020-04-30 2:08 ` Andrii Nakryiko
2020-05-01 17:23 ` Yonghong Song
2020-05-01 19:01 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 12/19] bpf: add bpf_seq_printf and bpf_seq_write helpers Yonghong Song
2020-04-28 6:02 ` kbuild test robot
2020-04-28 16:35 ` Yonghong Song
2020-04-30 20:06 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 13/19] bpf: handle spilled PTR_TO_BTF_ID properly when checking stack_boundary Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 14/19] bpf: support variable length array in tracing programs Yonghong Song
2020-04-30 20:04 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 15/19] tools/libbpf: add bpf_iter support Yonghong Song
2020-04-30 1:41 ` Andrii Nakryiko
2020-05-02 7:17 ` Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 16/19] tools/bpftool: add bpf_iter support for bptool Yonghong Song
2020-04-28 9:27 ` Quentin Monnet
2020-04-28 17:35 ` Yonghong Song
2020-04-29 8:37 ` Quentin Monnet
2020-04-27 20:12 ` [PATCH bpf-next v1 17/19] tools/bpf: selftests: add iterator programs for ipv6_route and netlink Yonghong Song
2020-04-30 2:12 ` Andrii Nakryiko
2020-04-27 20:12 ` [PATCH bpf-next v1 18/19] tools/bpf: selftests: add iter progs for bpf_map/task/task_file Yonghong Song
2020-04-27 20:12 ` [PATCH bpf-next v1 19/19] tools/bpf: selftests: add bpf_iter selftests Yonghong Song
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