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) <joel@xxxxxxxxxxxxxxxxx> --- 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