From a2c83fff582ae133d9f5bb187404ea9ce4da1f96 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Sun, 1 Mar 2015 12:31:42 +0100 Subject: ebpf: constify various function pointer structs We can move bpf_map_ops and bpf_verifier_ops and other structs into ro section, bpf_map_type_list and bpf_prog_type_list into read mostly. Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/bpf/helpers.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel/bpf/helpers.c') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 9e3414d85459..a3c7701a8b5e 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -41,7 +41,7 @@ static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) return (unsigned long) value; } -struct bpf_func_proto bpf_map_lookup_elem_proto = { +const struct bpf_func_proto bpf_map_lookup_elem_proto = { .func = bpf_map_lookup_elem, .gpl_only = false, .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, @@ -60,7 +60,7 @@ static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) return map->ops->map_update_elem(map, key, value, r4); } -struct bpf_func_proto bpf_map_update_elem_proto = { +const struct bpf_func_proto bpf_map_update_elem_proto = { .func = bpf_map_update_elem, .gpl_only = false, .ret_type = RET_INTEGER, @@ -80,7 +80,7 @@ static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) return map->ops->map_delete_elem(map, key); } -struct bpf_func_proto bpf_map_delete_elem_proto = { +const struct bpf_func_proto bpf_map_delete_elem_proto = { .func = bpf_map_delete_elem, .gpl_only = false, .ret_type = RET_INTEGER, -- cgit v1.2.3 From 03e69b508b6f7c51743055c9f61d1dfeadf4b635 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Sat, 14 Mar 2015 02:27:16 +0100 Subject: ebpf: add prandom helper for packet sampling This work is similar to commit 4cd3675ebf74 ("filter: added BPF random opcode") and adds a possibility for packet sampling in eBPF. Currently, this is only possible in classic BPF and useful to combine sampling with f.e. packet sockets, possible also with tc. Example function proto-type looks like: u32 (*prandom_u32)(void) = (void *)BPF_FUNC_get_prandom_u32; Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- kernel/bpf/helpers.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'kernel/bpf/helpers.c') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index a3c7701a8b5e..95eb59a045ea 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -11,6 +11,7 @@ */ #include #include +#include /* If kernel subsystem is allowing eBPF programs to call this function, * inside its own verifier_ops->get_func_proto() callback it should return @@ -87,3 +88,14 @@ const struct bpf_func_proto bpf_map_delete_elem_proto = { .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }; + +static u64 bpf_get_prandom_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + return prandom_u32(); +} + +const struct bpf_func_proto bpf_get_prandom_u32_proto = { + .func = bpf_get_prandom_u32, + .gpl_only = false, + .ret_type = RET_INTEGER, +}; -- cgit v1.2.3 From c04167ce2ca0ecaeaafef006cb0d65cf01b68e42 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Sat, 14 Mar 2015 02:27:17 +0100 Subject: ebpf: add helper for obtaining current processor id This patch adds the possibility to obtain raw_smp_processor_id() in eBPF. Currently, this is only possible in classic BPF where commit da2033c28226 ("filter: add SKF_AD_RXHASH and SKF_AD_CPU") has added facilities for this. Perhaps most importantly, this would also allow us to track per CPU statistics with eBPF maps, or to implement a poor-man's per CPU data structure through eBPF maps. Example function proto-type looks like: u32 (*smp_processor_id)(void) = (void *)BPF_FUNC_get_smp_processor_id; Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- kernel/bpf/helpers.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'kernel/bpf/helpers.c') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 95eb59a045ea..bd7f5988ed9c 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -12,6 +12,7 @@ #include #include #include +#include /* If kernel subsystem is allowing eBPF programs to call this function, * inside its own verifier_ops->get_func_proto() callback it should return @@ -99,3 +100,14 @@ const struct bpf_func_proto bpf_get_prandom_u32_proto = { .gpl_only = false, .ret_type = RET_INTEGER, }; + +static u64 bpf_get_smp_processor_id(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + return raw_smp_processor_id(); +} + +const struct bpf_func_proto bpf_get_smp_processor_id_proto = { + .func = bpf_get_smp_processor_id, + .gpl_only = false, + .ret_type = RET_INTEGER, +}; -- cgit v1.2.3