diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2019-05-14 01:18:55 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2019-05-14 19:47:29 +0200 |
| commit | c6110222c6f49ea68169f353565eb865488a8619 (patch) | |
| tree | 181de3f33b1e298789b1827b0103d6304f532a86 /kernel/bpf/syscall.c | |
| parent | tools/bpf: Sync kernel btf.h header (diff) | |
| download | linux-c6110222c6f49ea68169f353565eb865488a8619.tar.xz linux-c6110222c6f49ea68169f353565eb865488a8619.zip | |
bpf: add map_lookup_elem_sys_only for lookups from syscall side
Add a callback map_lookup_elem_sys_only() that map implementations
could use over map_lookup_elem() from system call side in case the
map implementation needs to handle the latter differently than from
the BPF data path. If map_lookup_elem_sys_only() is set, this will
be preferred pick for map lookups out of user space. This hook is
used in a follow-up fix for LRU map, but once development window
opens, we can convert other map types from map_lookup_elem() (here,
the one called upon BPF_MAP_LOOKUP_ELEM cmd is meant) over to use
the callback to simplify and clean up the latter.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/syscall.c')
| -rw-r--r-- | kernel/bpf/syscall.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index ad3ccf82f31d..cb5440b02e82 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -808,7 +808,10 @@ static int map_lookup_elem(union bpf_attr *attr) err = map->ops->map_peek_elem(map, value); } else { rcu_read_lock(); - ptr = map->ops->map_lookup_elem(map, key); + if (map->ops->map_lookup_elem_sys_only) + ptr = map->ops->map_lookup_elem_sys_only(map, key); + else + ptr = map->ops->map_lookup_elem(map, key); if (IS_ERR(ptr)) { err = PTR_ERR(ptr); } else if (!ptr) { |