diff options
author | Björn Töpel <bjorn.topel@intel.com> | 2021-03-08 12:29:06 +0100 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2021-03-10 01:06:34 +0100 |
commit | e6a4750ffe9d701c4d55212b14b615e63571d235 (patch) | |
tree | 0e807fb18dde8e4d6c7eb0495f25be9183bfdb2c /net | |
parent | selftests/bpf: Fix compiler warning in BPF_KPROBE definition in loop6.c (diff) | |
download | linux-e6a4750ffe9d701c4d55212b14b615e63571d235.tar.xz linux-e6a4750ffe9d701c4d55212b14b615e63571d235.zip |
bpf, xdp: Make bpf_redirect_map() a map operation
Currently the bpf_redirect_map() implementation dispatches to the
correct map-lookup function via a switch-statement. To avoid the
dispatching, this change adds bpf_redirect_map() as a map
operation. Each map provides its bpf_redirect_map() version, and
correct function is automatically selected by the BPF verifier.
A nice side-effect of the code movement is that the map lookup
functions are now local to the map implementation files, which removes
one additional function call.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210308112907.559576-2-bjorn.topel@gmail.com
Diffstat (limited to 'net')
-rw-r--r-- | net/core/filter.c | 39 | ||||
-rw-r--r-- | net/xdp/xskmap.c | 16 |
2 files changed, 17 insertions, 38 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 588b19ba0da8..183b0aa6b027 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3943,22 +3943,6 @@ void xdp_do_flush(void) } EXPORT_SYMBOL_GPL(xdp_do_flush); -static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index) -{ - switch (map->map_type) { - case BPF_MAP_TYPE_DEVMAP: - return __dev_map_lookup_elem(map, index); - case BPF_MAP_TYPE_DEVMAP_HASH: - return __dev_map_hash_lookup_elem(map, index); - case BPF_MAP_TYPE_CPUMAP: - return __cpu_map_lookup_elem(map, index); - case BPF_MAP_TYPE_XSKMAP: - return __xsk_map_lookup_elem(map, index); - default: - return NULL; - } -} - void bpf_clear_redirect_map(struct bpf_map *map) { struct bpf_redirect_info *ri; @@ -4112,28 +4096,7 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = { BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags) { - struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - - /* Lower bits of the flags are used as return code on lookup failure */ - if (unlikely(flags > XDP_TX)) - return XDP_ABORTED; - - ri->tgt_value = __xdp_map_lookup_elem(map, ifindex); - if (unlikely(!ri->tgt_value)) { - /* If the lookup fails we want to clear out the state in the - * redirect_info struct completely, so that if an eBPF program - * performs multiple lookups, the last one always takes - * precedence. - */ - WRITE_ONCE(ri->map, NULL); - return flags; - } - - ri->flags = flags; - ri->tgt_index = ifindex; - WRITE_ONCE(ri->map, map); - - return XDP_REDIRECT; + return map->ops->map_redirect(map, ifindex, flags); } static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c index 113fd9017203..fbeb4870f798 100644 --- a/net/xdp/xskmap.c +++ b/net/xdp/xskmap.c @@ -125,6 +125,16 @@ static int xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) return insn - insn_buf; } +static void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key) +{ + struct xsk_map *m = container_of(map, struct xsk_map, map); + + if (key >= map->max_entries) + return NULL; + + return READ_ONCE(m->xsk_map[key]); +} + static void *xsk_map_lookup_elem(struct bpf_map *map, void *key) { WARN_ON_ONCE(!rcu_read_lock_held()); @@ -215,6 +225,11 @@ static int xsk_map_delete_elem(struct bpf_map *map, void *key) return 0; } +static int xsk_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem); +} + void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs, struct xdp_sock **map_entry) { @@ -247,4 +262,5 @@ const struct bpf_map_ops xsk_map_ops = { .map_check_btf = map_check_no_btf, .map_btf_name = "xsk_map", .map_btf_id = &xsk_map_btf_id, + .map_redirect = xsk_map_redirect, }; |