On 7/1/20 6:40 PM, Alexei Starovoitov wrote:
From: Alexei Starovoitov <ast@xxxxxxxxxx>
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.
Thanks for implementing bpf iter for bpf_progs!
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
No selftests?!
They're coming as part of "usermode_driver for iterators" set.
This patch is trivial and independent, so sending it first.
Okay. Ack only with a few nits.
Acked-by: Yonghong Song <yhs@xxxxxx>
include/linux/bpf.h | 1 +
kernel/bpf/Makefile | 2 +-
kernel/bpf/prog_iter.c | 102 +++++++++++++++++++++++++++++++++++++++++
kernel/bpf/syscall.c | 19 ++++++++
4 files changed, 123 insertions(+), 1 deletion(-)
create mode 100644 kernel/bpf/prog_iter.c
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 0cd7f6884c5c..3c659f36591d 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/prog_iter.c b/kernel/bpf/prog_iter.c
new file mode 100644
index 000000000000..3080abd4d8ad
--- /dev/null
+++ b/kernel/bpf/prog_iter.c
@@ -0,0 +1,102 @@
+// 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 mid;
original field name "mid" is for "map_id".
Here, "pid" is a little bit misleading, maybe "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->mid);
+ 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;
+ struct bpf_prog *prog;
+
+ ++*pos;
+ ++info->mid;
+ bpf_prog_put((struct bpf_prog *)v);
+ prog = bpf_prog_get_curr_or_next(&info->mid);
+ if (!prog)
+ return NULL;
+
+ return prog;
You can just do "return bpf_prog_get_curr_or_next(&info->prog_id);"
"struct bpf_prog *prog" is not needed any more.
bpf_map_seq_next() has the same inefficiency. I think after a few
revisions I lost the sight.
+}
+
+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;
+}
+
[...]
