In preparation to use raw tracepoints for BPF directly from ftrace, move
the bpf_raw_tracepoint functionality into bpf_trace.c
Signed-off-by: Joel Fernandes (Google) <j...@joelfernandes.org>
---
include/linux/bpf_trace.h | 10 ++++++
kernel/bpf/syscall.c | 69 ++++++-------------------------------
kernel/trace/bpf_trace.c | 56 ++++++++++++++++++++++++++++++
kernel/trace/trace_events.c | 3 ++
4 files changed, 80 insertions(+), 58 deletions(-)
diff --git a/include/linux/bpf_trace.h b/include/linux/bpf_trace.h
index ddf896abcfb6..4a593827fd87 100644
--- a/include/linux/bpf_trace.h
+++ b/include/linux/bpf_trace.h
@@ -4,4 +4,14 @@
#include <trace/events/xdp.h>
+#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
+
+struct bpf_raw_tracepoint {
+ struct bpf_raw_event_map *btp;
+ struct bpf_prog *prog;
+};
+
+struct bpf_raw_tracepoint *bpf_raw_tracepoint_open(char *tp_name, int prog_fd);
+void bpf_raw_tracepoint_close(struct bpf_raw_tracepoint *tp);
+
#endif /* __LINUX_BPF_TRACE_H__ */
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 42d17f730780..2001949b33f1 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1737,21 +1737,11 @@ static int bpf_obj_get(const union bpf_attr *attr)
attr->file_flags);
}
-struct bpf_raw_tracepoint {
- struct bpf_raw_event_map *btp;
- struct bpf_prog *prog;
-};
-
static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
{
struct bpf_raw_tracepoint *raw_tp = filp->private_data;
- if (raw_tp->prog) {
- bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
- bpf_prog_put(raw_tp->prog);
- }
- bpf_put_raw_tracepoint(raw_tp->btp);
- kfree(raw_tp);
+ bpf_raw_tracepoint_close(raw_tp);
return 0;
}
@@ -1761,64 +1751,27 @@ static const struct file_operations bpf_raw_tp_fops = {
.write = bpf_dummy_write,
};
-#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
-
-static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
+static int bpf_raw_tracepoint_open_syscall(const union bpf_attr *attr)
{
- struct bpf_raw_tracepoint *raw_tp;
- struct bpf_raw_event_map *btp;
- struct bpf_prog *prog;
+ int tp_fd;
char tp_name[128];
- int tp_fd, err;
+ struct bpf_raw_tracepoint *raw_tp;
if (strncpy_from_user(tp_name,
u64_to_user_ptr(attr->raw_tracepoint.name),
sizeof(tp_name) - 1) < 0)
return -EFAULT;
tp_name[sizeof(tp_name) - 1] = 0;
- btp = bpf_get_raw_tracepoint(tp_name);
- if (!btp)
- return -ENOENT;
-
- raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
- if (!raw_tp) {
- err = -ENOMEM;
- goto out_put_btp;
- }
- raw_tp->btp = btp;
-
- prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
- if (IS_ERR(prog)) {
- err = PTR_ERR(prog);
- goto out_free_tp;
- }
- if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
- prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
- err = -EINVAL;
- goto out_put_prog;
- }
-
- err = bpf_probe_register(raw_tp->btp, prog);
- if (err)
- goto out_put_prog;
+ raw_tp = bpf_raw_tracepoint_open(tp_name, attr->raw_tracepoint.prog_fd);
+ if (IS_ERR(raw_tp))
+ return PTR_ERR(raw_tp);
- raw_tp->prog = prog;
tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
O_CLOEXEC);
- if (tp_fd < 0) {
- bpf_probe_unregister(raw_tp->btp, prog);
- err = tp_fd;
- goto out_put_prog;
- }
- return tp_fd;
+ if (tp_fd < 0)
+ bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
-out_put_prog:
- bpf_prog_put(prog);
-out_free_tp:
- kfree(raw_tp);
-out_put_btp:
- bpf_put_raw_tracepoint(btp);
- return err;
+ return tp_fd;
}
static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
@@ -2848,7 +2801,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *,
uattr, unsigned int, siz
err = bpf_obj_get_info_by_fd(&attr, uattr);
break;
case BPF_RAW_TRACEPOINT_OPEN:
- err = bpf_raw_tracepoint_open(&attr);
+ err = bpf_raw_tracepoint_open_syscall(&attr);
break;
case BPF_BTF_LOAD:
err = bpf_btf_load(&attr);
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 1c9a4745e596..c4b543bc617f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -7,6 +7,7 @@
#include <linux/slab.h>
#include <linux/bpf.h>
#include <linux/bpf_perf_event.h>
+#include <linux/bpf_trace.h>
#include <linux/filter.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
@@ -1413,3 +1414,58 @@ static int __init bpf_event_init(void)
fs_initcall(bpf_event_init);
#endif /* CONFIG_MODULES */
+
+void bpf_raw_tracepoint_close(struct bpf_raw_tracepoint *raw_tp)
+{
+ if (raw_tp->prog) {
+ bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
+ bpf_prog_put(raw_tp->prog);
+ }
+ bpf_put_raw_tracepoint(raw_tp->btp);
+ kfree(raw_tp);
+}
+
+struct bpf_raw_tracepoint *bpf_raw_tracepoint_open(char *tp_name, int prog_fd)
+{
+ struct bpf_raw_tracepoint *raw_tp;
+ struct bpf_raw_event_map *btp;
+ struct bpf_prog *prog;
+ int err;
+
+ btp = bpf_get_raw_tracepoint(tp_name);
+ if (!btp)
+ return ERR_PTR(-ENOENT);
+
+ raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
+ if (!raw_tp) {
+ err = -ENOMEM;
+ goto out_put_btp;
+ }
+ raw_tp->btp = btp;
+
+ prog = bpf_prog_get(prog_fd);
+ if (IS_ERR(prog)) {
+ err = PTR_ERR(prog);
+ goto out_free_tp;
+ }
+ if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
+ prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
+ err = -EINVAL;
+ goto out_put_prog;
+ }
+
+ err = bpf_probe_register(raw_tp->btp, prog);
+ if (err)
+ goto out_put_prog;
+
+ raw_tp->prog = prog;
+ return raw_tp;
+
+out_put_prog:
+ bpf_prog_put(prog);
+out_free_tp:
+ kfree(raw_tp);
+out_put_btp:
+ bpf_put_raw_tracepoint(btp);
+ return ERR_PTR(err);
+}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 0ce3db67f556..67851fb66b6b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2017,6 +2017,9 @@ event_create_dir(struct dentry *parent, struct
trace_event_file *file)
trace_create_file("trigger", 0644, file->dir, file,
&event_trigger_fops);
+
+ trace_create_file("bpf_attach", 0644, file->dir, file,
+ &bpf_attach_trigger_fops);
}
#ifdef CONFIG_HIST_TRIGGERS
--
2.22.0.410.gd8fdbe21b5-goog
