Merge branch 'bpf-sock-hashmap'

John Fastabend says:

====================
In the original sockmap implementation we got away with using an
array similar to devmap. However, unlike devmap where an ifindex
has a nice 1:1 function into the map we have found some use cases
with sockets that need to be referenced using longer keys.

This series adds support for a sockhash map reusing as much of
the sockmap code as possible. I made the decision to add sockhash
specific helpers vs trying to generalize the existing helpers
because (a) they have sockmap in the name and (b) the keys are
different types. I prefer to be explicit here rather than play
type games or do something else tricky.

To test this we duplicate all the sockmap testing except swap out
the sockmap with a sockhash.

v2: fix file stats and add v2 tag
v3: move tool updates into test patch, move bpftool updates into
    its own patch, and fixup the test patch stats to catch the
    renamed file and provide only diffs ± on that.
v4: Add documentation to UAPI bpf.h
v5: Add documentation to tools UAPI bpf.h
v6: 'git add' test_sockhash_kern.c which was previously missing
    but was not causing issues because of typo in test script,
    noticed by Daniel. After this the git format-patch -M option
    no longer tracks the rename of the test_sockmap_kern files for
    some reason. I guess the diff has exceeded some threshold.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

3 files changed, 10 insertions, 2 deletions

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index a38e474bf7ee..ed0122b45b63 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -668,6 +668,7 @@ static inline void bpf_map_offload_map_free(struct bpf_map *map)
 
 #if defined(CONFIG_STREAM_PARSER) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_INET)
 struct sock  *__sock_map_lookup_elem(struct bpf_map *map, u32 key);
+struct sock  *__sock_hash_lookup_elem(struct bpf_map *map, void *key);
 int sock_map_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type);
 #else
 static inline struct sock  *__sock_map_lookup_elem(struct bpf_map *map, u32 key)
@@ -675,6 +676,12 @@ static inline struct sock  *__sock_map_lookup_elem(struct bpf_map *map, u32 key)
 	return NULL;
 }
 
+static inline struct sock  *__sock_hash_lookup_elem(struct bpf_map *map,
+						    void *key)
+{
+	return NULL;
+}
+
 static inline int sock_map_prog(struct bpf_map *map,
 				struct bpf_prog *prog,
 				u32 type)
@@ -724,6 +731,7 @@ extern const struct bpf_func_proto bpf_get_current_comm_proto;
 extern const struct bpf_func_proto bpf_get_stackid_proto;
 extern const struct bpf_func_proto bpf_get_stack_proto;
 extern const struct bpf_func_proto bpf_sock_map_update_proto;
+extern const struct bpf_func_proto bpf_sock_hash_update_proto;
 
 /* Shared helpers among cBPF and eBPF. */
 void bpf_user_rnd_init_once(void);
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index d7df1b323082..b67f8793de0d 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -47,6 +47,7 @@ BPF_MAP_TYPE(BPF_MAP_TYPE_HASH_OF_MAPS, htab_of_maps_map_ops)
 BPF_MAP_TYPE(BPF_MAP_TYPE_DEVMAP, dev_map_ops)
 #if defined(CONFIG_STREAM_PARSER) && defined(CONFIG_INET)
 BPF_MAP_TYPE(BPF_MAP_TYPE_SOCKMAP, sock_map_ops)
+BPF_MAP_TYPE(BPF_MAP_TYPE_SOCKHASH, sock_hash_ops)
 #endif
 BPF_MAP_TYPE(BPF_MAP_TYPE_CPUMAP, cpu_map_ops)
 #if defined(CONFIG_XDP_SOCKETS)
diff --git a/include/linux/filter.h b/include/linux/filter.h
index da7e16523128..9dbcb9d55921 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -515,9 +515,8 @@ struct sk_msg_buff {
 	int sg_end;
 	struct scatterlist sg_data[MAX_SKB_FRAGS];
 	bool sg_copy[MAX_SKB_FRAGS];
-	__u32 key;
 	__u32 flags;
-	struct bpf_map *map;
+	struct sock *sk_redir;
 	struct sk_buff *skb;
 	struct list_head list;
 };