[PATCH net-next 1/2] ebpf: allow bpf_ktime_get_ns_proto also for networking
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2015-05-29 21:23:13
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), bpf [security & lsm] (security audit and enforcement using bpf), bpf [tracing], networking [general], the rest, tracing · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Martin KaFai Lau, KP Singh, Matt Bobrowski, Song Liu, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
As this is already exported from tracing side via commit d9847d310ab4
("tracing: Allow BPF programs to call bpf_ktime_get_ns()"), we might
as well want to move it to the core, so also networking users can make
use of it, e.g. to measure diffs for certain flows from ingress/egress.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <redacted>
Cc: Ingo Molnar <mingo@kernel.org>
---
include/linux/bpf.h | 1 +
kernel/bpf/core.c | 1 +
kernel/bpf/helpers.c | 13 +++++++++++++
kernel/trace/bpf_trace.c | 12 ------------
net/core/filter.c | 2 ++
5 files changed, 17 insertions(+), 12 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 8821b9a..0fb0e72 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -182,5 +182,6 @@ extern const struct bpf_func_proto bpf_map_delete_elem_proto; extern const struct bpf_func_proto bpf_get_prandom_u32_proto; extern const struct bpf_func_proto bpf_get_smp_processor_id_proto; extern const struct bpf_func_proto bpf_tail_call_proto; +extern const struct bpf_func_proto bpf_ktime_get_ns_proto; #endif /* _LINUX_BPF_H */
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index d44b25c..4548422 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c@@ -734,6 +734,7 @@ const struct bpf_func_proto bpf_map_delete_elem_proto __weak; const struct bpf_func_proto bpf_get_prandom_u32_proto __weak; const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak; +const struct bpf_func_proto bpf_ktime_get_ns_proto __weak; /* To execute LD_ABS/LD_IND instructions __bpf_prog_run() may call * skb_copy_bits(), so provide a weak definition of it for NET-less config.
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index bd7f598..b3aaabd 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c@@ -13,6 +13,7 @@ #include <linux/rcupdate.h> #include <linux/random.h> #include <linux/smp.h> +#include <linux/ktime.h> /* If kernel subsystem is allowing eBPF programs to call this function, * inside its own verifier_ops->get_func_proto() callback it should return
@@ -111,3 +112,15 @@ const struct bpf_func_proto bpf_get_smp_processor_id_proto = { .gpl_only = false, .ret_type = RET_INTEGER, }; + +static u64 bpf_ktime_get_ns(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + /* NMI safe access to clock monotonic */ + return ktime_get_mono_fast_ns(); +} + +const struct bpf_func_proto bpf_ktime_get_ns_proto = { + .func = bpf_ktime_get_ns, + .gpl_only = true, + .ret_type = RET_INTEGER, +};
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 646445e..50c4015 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c@@ -79,18 +79,6 @@ static const struct bpf_func_proto bpf_probe_read_proto = { .arg3_type = ARG_ANYTHING, }; -static u64 bpf_ktime_get_ns(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) -{ - /* NMI safe access to clock monotonic */ - return ktime_get_mono_fast_ns(); -} - -static const struct bpf_func_proto bpf_ktime_get_ns_proto = { - .func = bpf_ktime_get_ns, - .gpl_only = true, - .ret_type = RET_INTEGER, -}; - /* * limited trace_printk() * only %d %u %x %ld %lu %lx %lld %llu %llx %p conversion specifiers allowed
diff --git a/net/core/filter.c b/net/core/filter.c
index 3adcca6..2a7c70f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -1423,6 +1423,8 @@ sk_filter_func_proto(enum bpf_func_id func_id) return &bpf_get_smp_processor_id_proto; case BPF_FUNC_tail_call: return &bpf_tail_call_proto; + case BPF_FUNC_ktime_get_ns: + return &bpf_ktime_get_ns_proto; default: return NULL; }
--
1.9.3