From: Alexei Starovoitov <a...@kernel.org>
It's mostly a copy paste of commit 6086d29def80 ("bpf: Add bpf_map iterator")
that is use to implement bpf_seq_file opreations to traverse all bpf programs.
Signed-off-by: Alexei Starovoitov <a...@kernel.org>
Acked-by: Yonghong Song <y...@fb.com>
---
include/linux/bpf.h | 1 +
kernel/bpf/Makefile | 2 +-
kernel/bpf/map_iter.c | 13 ++----
kernel/bpf/prog_iter.c | 97 ++++++++++++++++++++++++++++++++++++++++++
kernel/bpf/syscall.c | 19 +++++++++
5 files changed, 122 insertions(+), 10 deletions(-)
create mode 100644 kernel/bpf/prog_iter.c
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index c67c88ad35f8..4ede2b0298b3 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1112,6 +1112,7 @@ 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);
+struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id);
extern int sysctl_unprivileged_bpf_disabled;
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 1131a921e1a6..e6eb9c0402da 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 map_iter.o task_iter.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o
bpf_iter.o map_iter.o task_iter.o prog_iter.o
obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o
bpf_lru_list.o lpm_trie.o map_in_map.o
obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o
obj-$(CONFIG_BPF_SYSCALL) += disasm.o
diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c
index c69071e334bf..343c1df100cf 100644
--- a/kernel/bpf/map_iter.c
+++ b/kernel/bpf/map_iter.c
@@ -6,7 +6,7 @@
#include <linux/kernel.h>
struct bpf_iter_seq_map_info {
- u32 mid;
+ u32 map_id;
};
static void *bpf_map_seq_start(struct seq_file *seq, loff_t *pos)
@@ -14,7 +14,7 @@ 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;
- map = bpf_map_get_curr_or_next(&info->mid);
+ map = bpf_map_get_curr_or_next(&info->map_id);
if (!map)
return NULL;
@@ -25,16 +25,11 @@ static void *bpf_map_seq_start(struct seq_file *seq, loff_t
*pos)
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->mid;
+ ++info->map_id;
bpf_map_put((struct bpf_map *)v);
- map = bpf_map_get_curr_or_next(&info->mid);
- if (!map)
- return NULL;
-
- return map;
+ return bpf_map_get_curr_or_next(&info->map_id);
}
struct bpf_iter__bpf_map {
diff --git a/kernel/bpf/prog_iter.c b/kernel/bpf/prog_iter.c
new file mode 100644
index 000000000000..b5824382eb7d
--- /dev/null
+++ b/kernel/bpf/prog_iter.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2020 Facebook */
+#include <linux/bpf.h>
+#include <linux/fs.h>
+#include <linux/filter.h>
+#include <linux/kernel.h>
+
+struct bpf_iter_seq_prog_info {
+ u32 prog_id;
+};
+
+static void *bpf_prog_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct bpf_iter_seq_prog_info *info = seq->private;
+ struct bpf_prog *prog;
+
+ prog = bpf_prog_get_curr_or_next(&info->prog_id);
+ if (!prog)
+ return NULL;
+
+ ++*pos;
+ return prog;
+}
+
+static void *bpf_prog_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct bpf_iter_seq_prog_info *info = seq->private;
+
+ ++*pos;
+ ++info->prog_id;
+ bpf_prog_put((struct bpf_prog *)v);
+ return bpf_prog_get_curr_or_next(&info->prog_id);
+}
+
+struct bpf_iter__bpf_prog {
+ __bpf_md_ptr(struct bpf_iter_meta *, meta);
+ __bpf_md_ptr(struct bpf_prog *, prog);
+};
+
+DEFINE_BPF_ITER_FUNC(bpf_prog, struct bpf_iter_meta *meta, struct bpf_prog
*prog)
+
+static int __bpf_prog_seq_show(struct seq_file *seq, void *v, bool in_stop)
+{
+ struct bpf_iter__bpf_prog ctx;
+ struct bpf_iter_meta meta;
+ struct bpf_prog *prog;
+ int ret = 0;
+
+ ctx.meta = &meta;
+ ctx.prog = 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_prog_seq_show(struct seq_file *seq, void *v)
+{
+ return __bpf_prog_seq_show(seq, v, false);
+}
+
+static void bpf_prog_seq_stop(struct seq_file *seq, void *v)
+{
+ if (!v)
+ (void)__bpf_prog_seq_show(seq, v, true);
+ else
+ bpf_prog_put((struct bpf_prog *)v);
+}
+
+static const struct seq_operations bpf_prog_seq_ops = {
+ .start = bpf_prog_seq_start,
+ .next = bpf_prog_seq_next,
+ .stop = bpf_prog_seq_stop,
+ .show = bpf_prog_seq_show,
+};
+
+static const struct bpf_iter_reg bpf_prog_reg_info = {
+ .target = "bpf_prog",
+ .seq_ops = &bpf_prog_seq_ops,
+ .init_seq_private = NULL,
+ .fini_seq_private = NULL,
+ .seq_priv_size = sizeof(struct bpf_iter_seq_prog_info),
+ .ctx_arg_info_size = 1,
+ .ctx_arg_info = {
+ { offsetof(struct bpf_iter__bpf_prog, prog),
+ PTR_TO_BTF_ID_OR_NULL },
+ },
+};
+
+static int __init bpf_prog_iter_init(void)
+{
+ return bpf_iter_reg_target(&bpf_prog_reg_info);
+}
+
+late_initcall(bpf_prog_iter_init);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7ea9dfbebd8c..86df3daa13f6 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3036,6 +3036,25 @@ struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
return map;
}
+struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
+{
+ struct bpf_prog *prog;
+
+ spin_lock_bh(&prog_idr_lock);
+again:
+ prog = idr_get_next(&prog_idr, id);
+ if (prog) {
+ prog = bpf_prog_inc_not_zero(prog);
+ if (IS_ERR(prog)) {
+ (*id)++;
+ goto again;
+ }
+ }
+ spin_unlock_bh(&prog_idr_lock);
+
+ return prog;
+}
+
#define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
struct bpf_prog *bpf_prog_by_id(u32 id)
--
2.23.0
