Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Andrii Nakryiko says:

====================
bpf-next 2022-11-11

We've added 49 non-merge commits during the last 9 day(s) which contain
a total of 68 files changed, 3592 insertions(+), 1371 deletions(-).

The main changes are:

1) Veristat tool improvements to support custom filtering, sorting, and replay
   of results, from Andrii Nakryiko.

2) BPF verifier precision tracking fixes and improvements,
   from Andrii Nakryiko.

3) Lots of new BPF documentation for various BPF maps, from Dave Tucker,
   Donald Hunter, Maryam Tahhan, Bagas Sanjaya.

4) BTF dedup improvements and libbpf's hashmap interface clean ups, from
   Eduard Zingerman.

5) Fix veth driver panic if XDP program is attached before veth_open, from
   John Fastabend.

6) BPF verifier clean ups and fixes in preparation for follow up features,
   from Kumar Kartikeya Dwivedi.

7) Add access to hwtstamp field from BPF sockops programs,
   from Martin KaFai Lau.

8) Various fixes for BPF selftests and samples, from Artem Savkov,
   Domenico Cerasuolo, Kang Minchul, Rong Tao, Yang Jihong.

9) Fix redirection to tunneling device logic, preventing skb->len == 0, from
   Stanislav Fomichev.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (49 commits)
  selftests/bpf: fix veristat's singular file-or-prog filter
  selftests/bpf: Test skops->skb_hwtstamp
  selftests/bpf: Fix incorrect ASSERT in the tcp_hdr_options test
  bpf: Add hwtstamp field for the sockops prog
  selftests/bpf: Fix xdp_synproxy compilation failure in 32-bit arch
  bpf, docs: Document BPF_MAP_TYPE_ARRAY
  docs/bpf: Document BPF map types QUEUE and STACK
  docs/bpf: Document BPF ARRAY_OF_MAPS and HASH_OF_MAPS
  docs/bpf: Document BPF_MAP_TYPE_CPUMAP map
  docs/bpf: Document BPF_MAP_TYPE_LPM_TRIE map
  libbpf: Hashmap.h update to fix build issues using LLVM14
  bpf: veth driver panics when xdp prog attached before veth_open
  selftests: Fix test group SKIPPED result
  selftests/bpf: Tests for btf_dedup_resolve_fwds
  libbpf: Resolve unambigous forward declarations
  libbpf: Hashmap interface update to allow both long and void* keys/values
  samples/bpf: Fix sockex3 error: Missing BPF prog type
  selftests/bpf: Fix u32 variable compared with less than zero
  Documentation: bpf: Escape underscore in BPF type name prefix
  selftests/bpf: Use consistent build-id type for liburandom_read.so
  ...
====================

Link: https://lore.kernel.org/r/20221111233733.1088228-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 57 insertions, 34 deletions

diff --git a/tools/lib/bpf/hashmap.h b/tools/lib/bpf/hashmap.h
index 10a4c4cd13cf..0a5bf1937a7c 100644
--- a/tools/lib/bpf/hashmap.h
+++ b/tools/lib/bpf/hashmap.h
@@ -40,12 +40,32 @@ static inline size_t str_hash(const char *s)
 	return h;
 }
 
-typedef size_t (*hashmap_hash_fn)(const void *key, void *ctx);
-typedef bool (*hashmap_equal_fn)(const void *key1, const void *key2, void *ctx);
+typedef size_t (*hashmap_hash_fn)(long key, void *ctx);
+typedef bool (*hashmap_equal_fn)(long key1, long key2, void *ctx);
 
+/*
+ * Hashmap interface is polymorphic, keys and values could be either
+ * long-sized integers or pointers, this is achieved as follows:
+ * - interface functions that operate on keys and values are hidden
+ *   behind auxiliary macros, e.g. hashmap_insert <-> hashmap__insert;
+ * - these auxiliary macros cast the key and value parameters as
+ *   long or long *, so the user does not have to specify the casts explicitly;
+ * - for pointer parameters (e.g. old_key) the size of the pointed
+ *   type is verified by hashmap_cast_ptr using _Static_assert;
+ * - when iterating using hashmap__for_each_* forms
+ *   hasmap_entry->key should be used for integer keys and
+ *   hasmap_entry->pkey should be used for pointer keys,
+ *   same goes for values.
+ */
 struct hashmap_entry {
-	const void *key;
-	void *value;
+	union {
+		long key;
+		const void *pkey;
+	};
+	union {
+		long value;
+		void *pvalue;
+	};
 	struct hashmap_entry *next;
 };
 
@@ -102,6 +122,13 @@ enum hashmap_insert_strategy {
 	HASHMAP_APPEND,
 };
 
+#define hashmap_cast_ptr(p) ({								\
+	_Static_assert((__builtin_constant_p((p)) ? (p) == NULL : 0) ||			\
+				sizeof(*(p)) == sizeof(long),				\
+		       #p " pointee should be a long-sized integer or a pointer");	\
+	(long *)(p);									\
+})
+
 /*
  * hashmap__insert() adds key/value entry w/ various semantics, depending on
  * provided strategy value. If a given key/value pair replaced already
@@ -109,42 +136,38 @@ enum hashmap_insert_strategy {
  * through old_key and old_value to allow calling code do proper memory
  * management.
  */
-int hashmap__insert(struct hashmap *map, const void *key, void *value,
-		    enum hashmap_insert_strategy strategy,
-		    const void **old_key, void **old_value);
+int hashmap_insert(struct hashmap *map, long key, long value,
+		   enum hashmap_insert_strategy strategy,
+		   long *old_key, long *old_value);
 
-static inline int hashmap__add(struct hashmap *map,
-			       const void *key, void *value)
-{
-	return hashmap__insert(map, key, value, HASHMAP_ADD, NULL, NULL);
-}
+#define hashmap__insert(map, key, value, strategy, old_key, old_value) \
+	hashmap_insert((map), (long)(key), (long)(value), (strategy),  \
+		       hashmap_cast_ptr(old_key),		       \
+		       hashmap_cast_ptr(old_value))
 
-static inline int hashmap__set(struct hashmap *map,
-			       const void *key, void *value,
-			       const void **old_key, void **old_value)
-{
-	return hashmap__insert(map, key, value, HASHMAP_SET,
-			       old_key, old_value);
-}
+#define hashmap__add(map, key, value) \
+	hashmap__insert((map), (key), (value), HASHMAP_ADD, NULL, NULL)
 
-static inline int hashmap__update(struct hashmap *map,
-				  const void *key, void *value,
-				  const void **old_key, void **old_value)
-{
-	return hashmap__insert(map, key, value, HASHMAP_UPDATE,
-			       old_key, old_value);
-}
+#define hashmap__set(map, key, value, old_key, old_value) \
+	hashmap__insert((map), (key), (value), HASHMAP_SET, (old_key), (old_value))
 
-static inline int hashmap__append(struct hashmap *map,
-				  const void *key, void *value)
-{
-	return hashmap__insert(map, key, value, HASHMAP_APPEND, NULL, NULL);
-}
+#define hashmap__update(map, key, value, old_key, old_value) \
+	hashmap__insert((map), (key), (value), HASHMAP_UPDATE, (old_key), (old_value))
+
+#define hashmap__append(map, key, value) \
+	hashmap__insert((map), (key), (value), HASHMAP_APPEND, NULL, NULL)
+
+bool hashmap_delete(struct hashmap *map, long key, long *old_key, long *old_value);
+
+#define hashmap__delete(map, key, old_key, old_value)		       \
+	hashmap_delete((map), (long)(key),			       \
+		       hashmap_cast_ptr(old_key),		       \
+		       hashmap_cast_ptr(old_value))
 
-bool hashmap__delete(struct hashmap *map, const void *key,
-		     const void **old_key, void **old_value);
+bool hashmap_find(const struct hashmap *map, long key, long *value);
 
-bool hashmap__find(const struct hashmap *map, const void *key, void **value);
+#define hashmap__find(map, key, value) \
+	hashmap_find((map), (long)(key), hashmap_cast_ptr(value))
 
 /*
  * hashmap__for_each_entry - iterate over all entries in hashmap