Merge branch 'bpf-libbpf-btf-defined-maps'

Andrii Nakryiko says:

====================
This patch set implements initial version (as discussed at LSF/MM2019
conference) of a new way to specify BPF maps, relying on BTF type information,
which allows for easy extensibility, preserving forward and backward
compatibility. See details and examples in description for patch #6.

[0] contains an outline of follow up extensions to be added after this basic
set of features lands. They are useful by itself, but also allows to bring
libbpf to feature-parity with iproute2 BPF loader. That should open a path
forward for BPF loaders unification.

Patch #1 centralizes commonly used min/max macro in libbpf_internal.h.
Patch #2 extracts .BTF and .BTF.ext loading loging from elf_collect().
Patch #3 simplifies elf_collect() error-handling logic.
Patch #4 refactors map initialization logic into user-provided maps and global
data maps, in preparation to adding another way (BTF-defined maps).
Patch #5 adds support for map definitions in multiple ELF sections and
deprecates bpf_object__find_map_by_offset() API which doesn't appear to be
used anymore and makes assumption that all map definitions reside in single
ELF section.
Patch #6 splits BTF intialization from sanitization/loading into kernel to
preserve original BTF at the time of map initialization.
Patch #7 adds support for BTF-defined maps.
Patch #8 adds new test for BTF-defined map definition.
Patches #9-11 convert test BPF map definitions to use BTF way.

[0] https://lore.kernel.org/bpf/CAEf4BzbfdG2ub7gCi0OYqBrUoChVHWsmOntWAkJt47=FE+km+A@mail.gmail.com/

v1->v2:
- more BTF-sanity checks in parsing map definitions (Song);
- removed confusing usage of "attribute", switched to "field;
- split off elf_collect() refactor from btf loading refactor (Song);
- split selftests conversion into 3 patches (Stanislav):
  1. test already relying on BTF;
  2. tests w/ custom types as key/value (so benefiting from BTF);
  3. all the rest tests (integers as key/value, special maps w/o BTF support).
- smaller code improvements (Song);

rfc->v1:
- error out on unknown field by default (Stanislav, Jakub, Lorenz);
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/lib/bpf/bpf.c

@@ -26,10 +26,11 @@
 #include <memory.h>
 #include <unistd.h>
 #include <asm/unistd.h>
+#include <errno.h>
 #include <linux/bpf.h>
 #include "bpf.h"
 #include "libbpf.h"
-#include <errno.h>
+#include "libbpf_internal.h"
 
 /*
  * When building perf, unistd.h is overridden. __NR_bpf is
@@ -53,10 +54,6 @@
 # endif
 #endif
 
-#ifndef min
-#define min(x, y) ((x) < (y) ? (x) : (y))
-#endif
-
 static inline __u64 ptr_to_u64(const void *ptr)
 {
 	return (__u64) (unsigned long) ptr;

tools/lib/bpf/bpf_prog_linfo.c

@@ -6,10 +6,7 @@
 #include <linux/err.h>
 #include <linux/bpf.h>
 #include "libbpf.h"
-
-#ifndef min
-#define min(x, y) ((x) < (y) ? (x) : (y))
-#endif
+#include "libbpf_internal.h"
 
 struct bpf_prog_linfo {
 	void *raw_linfo;

tools/lib/bpf/btf.c

@@ -16,9 +16,6 @@
 #include "libbpf_internal.h"
 #include "hashmap.h"
 
-#define max(a, b) ((a) > (b) ? (a) : (b))
-#define min(a, b) ((a) < (b) ? (a) : (b))
-
 #define BTF_MAX_NR_TYPES 0x7fffffff
 #define BTF_MAX_STR_OFFSET 0x7fffffff
 

tools/lib/bpf/btf.h

@@ -17,6 +17,7 @@ extern "C" {
 
 #define BTF_ELF_SEC ".BTF"
 #define BTF_EXT_ELF_SEC ".BTF.ext"
+#define MAPS_ELF_SEC ".maps"
 
 struct btf;
 struct btf_ext;

tools/lib/bpf/btf_dump.c

@@ -18,9 +18,6 @@
 #include "libbpf.h"
 #include "libbpf_internal.h"
 
-#define min(x, y) ((x) < (y) ? (x) : (y))
-#define max(x, y) ((x) < (y) ? (y) : (x))
-
 static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
 static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;
 

tools/lib/bpf/libbpf.c

@@ -207,7 +207,8 @@ static const char * const libbpf_type_to_btf_name[] = {
 struct bpf_map {
 	int fd;
 	char *name;
-	size_t offset;
+	int sec_idx;
+	size_t sec_offset;
 	int map_ifindex;
 	int inner_map_fd;
 	struct bpf_map_def def;
@@ -234,6 +235,7 @@ struct bpf_object {
 	size_t nr_programs;
 	struct bpf_map *maps;
 	size_t nr_maps;
+	size_t maps_cap;
 	struct bpf_secdata sections;
 
 	bool loaded;
@@ -260,6 +262,7 @@ struct bpf_object {
 		} *reloc;
 		int nr_reloc;
 		int maps_shndx;
+		int btf_maps_shndx;
 		int text_shndx;
 		int data_shndx;
 		int rodata_shndx;
@@ -512,6 +515,7 @@ static struct bpf_object *bpf_object__new(const char *path,
 	obj->efile.obj_buf = obj_buf;
 	obj->efile.obj_buf_sz = obj_buf_sz;
 	obj->efile.maps_shndx = -1;
+	obj->efile.btf_maps_shndx = -1;
 	obj->efile.data_shndx = -1;
 	obj->efile.rodata_shndx = -1;
 	obj->efile.bss_shndx = -1;
@@ -646,7 +650,9 @@ static int compare_bpf_map(const void *_a, const void *_b)
 	const struct bpf_map *a = _a;
 	const struct bpf_map *b = _b;
 
-	return a->offset - b->offset;
+	if (a->sec_idx != b->sec_idx)
+		return a->sec_idx - b->sec_idx;
+	return a->sec_offset - b->sec_offset;
 }
 
 static bool bpf_map_type__is_map_in_map(enum bpf_map_type type)
@@ -763,24 +769,55 @@ int bpf_object__variable_offset(const struct bpf_object *obj, const char *name,
 	return -ENOENT;
 }
 
-static bool bpf_object__has_maps(const struct bpf_object *obj)
+static struct bpf_map *bpf_object__add_map(struct bpf_object *obj)
 {
-	return obj->efile.maps_shndx >= 0 ||
-	       obj->efile.data_shndx >= 0 ||
-	       obj->efile.rodata_shndx >= 0 ||
-	       obj->efile.bss_shndx >= 0;
+	struct bpf_map *new_maps;
+	size_t new_cap;
+	int i;
+
+	if (obj->nr_maps < obj->maps_cap)
+		return &obj->maps[obj->nr_maps++];
+
+	new_cap = max(4ul, obj->maps_cap * 3 / 2);
+	new_maps = realloc(obj->maps, new_cap * sizeof(*obj->maps));
+	if (!new_maps) {
+		pr_warning("alloc maps for object failed\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	obj->maps_cap = new_cap;
+	obj->maps = new_maps;
+
+	/* zero out new maps */
+	memset(obj->maps + obj->nr_maps, 0,
+	       (obj->maps_cap - obj->nr_maps) * sizeof(*obj->maps));
+	/*
+	 * fill all fd with -1 so won't close incorrect fd (fd=0 is stdin)
+	 * when failure (zclose won't close negative fd)).
+	 */
+	for (i = obj->nr_maps; i < obj->maps_cap; i++) {
+		obj->maps[i].fd = -1;
+		obj->maps[i].inner_map_fd = -1;
+	}
+
+	return &obj->maps[obj->nr_maps++];
 }
 
 static int
-bpf_object__init_internal_map(struct bpf_object *obj, struct bpf_map *map,
-			      enum libbpf_map_type type, Elf_Data *data,
-			      void **data_buff)
+bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type,
+			      int sec_idx, Elf_Data *data, void **data_buff)
 {
-	struct bpf_map_def *def = &map->def;
 	char map_name[BPF_OBJ_NAME_LEN];
+	struct bpf_map_def *def;
+	struct bpf_map *map;
+
+	map = bpf_object__add_map(obj);
+	if (IS_ERR(map))
+		return PTR_ERR(map);
 
 	map->libbpf_type = type;
-	map->offset = ~(typeof(map->offset))0;
+	map->sec_idx = sec_idx;
+	map->sec_offset = 0;
 	snprintf(map_name, sizeof(map_name), "%.8s%.7s", obj->name,
 		 libbpf_type_to_btf_name[type]);
 	map->name = strdup(map_name);
@@ -788,7 +825,10 @@ bpf_object__init_internal_map(struct bpf_object *obj, struct bpf_map *map,
 		pr_warning("failed to alloc map name\n");
 		return -ENOMEM;
 	}
+	pr_debug("map '%s' (global data): at sec_idx %d, offset %zu.\n",
+		 map_name, map->sec_idx, map->sec_offset);
 
+	def = &map->def;
 	def->type = BPF_MAP_TYPE_ARRAY;
 	def->key_size = sizeof(int);
 	def->value_size = data->d_size;
@@ -808,22 +848,55 @@ bpf_object__init_internal_map(struct bpf_object *obj, struct bpf_map *map,
 	return 0;
 }
 
-static int bpf_object__init_maps(struct bpf_object *obj, int flags)
+static int bpf_object__init_global_data_maps(struct bpf_object *obj)
+{
+	int err;
+
+	if (!obj->caps.global_data)
+		return 0;
+	/*
+	 * Populate obj->maps with libbpf internal maps.
+	 */
+	if (obj->efile.data_shndx >= 0) {
+		err = bpf_object__init_internal_map(obj, LIBBPF_MAP_DATA,
+						    obj->efile.data_shndx,
+						    obj->efile.data,
+						    &obj->sections.data);
+		if (err)
+			return err;
+	}
+	if (obj->efile.rodata_shndx >= 0) {
+		err = bpf_object__init_internal_map(obj, LIBBPF_MAP_RODATA,
+						    obj->efile.rodata_shndx,
+						    obj->efile.rodata,
+						    &obj->sections.rodata);
+		if (err)
+			return err;
+	}
+	if (obj->efile.bss_shndx >= 0) {
+		err = bpf_object__init_internal_map(obj, LIBBPF_MAP_BSS,
+						    obj->efile.bss_shndx,
+						    obj->efile.bss, NULL);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict)
 {
-	int i, map_idx, map_def_sz = 0, nr_syms, nr_maps = 0, nr_maps_glob = 0;
-	bool strict = !(flags & MAPS_RELAX_COMPAT);
 	Elf_Data *symbols = obj->efile.symbols;
+	int i, map_def_sz = 0, nr_maps = 0, nr_syms;
 	Elf_Data *data = NULL;
-	int ret = 0;
+	Elf_Scn *scn;
+
+	if (obj->efile.maps_shndx < 0)
+		return 0;
 
 	if (!symbols)
 		return -EINVAL;
-	nr_syms = symbols->d_size / sizeof(GElf_Sym);
-
-	if (obj->efile.maps_shndx >= 0) {
-		Elf_Scn *scn = elf_getscn(obj->efile.elf,
-					  obj->efile.maps_shndx);
 
+	scn = elf_getscn(obj->efile.elf, obj->efile.maps_shndx);
 	if (scn)
 		data = elf_getdata(scn, NULL);
 	if (!scn || !data) {
@@ -831,7 +904,6 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 			   obj->efile.maps_shndx);
 		return -EINVAL;
 	}
-	}
 
 	/*
 	 * Count number of maps. Each map has a name.
@@ -840,16 +912,8 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 	 *
 	 * TODO: Detect array of map and report error.
 	 */
-	if (obj->caps.global_data) {
-		if (obj->efile.data_shndx >= 0)
-			nr_maps_glob++;
-		if (obj->efile.rodata_shndx >= 0)
-			nr_maps_glob++;
-		if (obj->efile.bss_shndx >= 0)
-			nr_maps_glob++;
-	}
-
-	for (i = 0; data && i < nr_syms; i++) {
+	nr_syms = symbols->d_size / sizeof(GElf_Sym);
+	for (i = 0; i < nr_syms; i++) {
 		GElf_Sym sym;
 
 		if (!gelf_getsym(symbols, i, &sym))
@@ -858,14 +922,9 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 			continue;
 		nr_maps++;
 	}
-
-	if (!nr_maps && !nr_maps_glob)
-		return 0;
-
 	/* Assume equally sized map definitions */
-	if (data) {
-		pr_debug("maps in %s: %d maps in %zd bytes\n", obj->path,
-			 nr_maps, data->d_size);
+	pr_debug("maps in %s: %d maps in %zd bytes\n",
+		 obj->path, nr_maps, data->d_size);
 
 	map_def_sz = data->d_size / nr_maps;
 	if (!data->d_size || (data->d_size % nr_maps) != 0) {
@@ -874,63 +933,48 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 			   obj->path, nr_maps, data->d_size);
 		return -EINVAL;
 	}
-	}
-
-	nr_maps += nr_maps_glob;
-	obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
-	if (!obj->maps) {
-		pr_warning("alloc maps for object failed\n");
-		return -ENOMEM;
-	}
-	obj->nr_maps = nr_maps;
 
-	for (i = 0; i < nr_maps; i++) {
-		/*
-		 * fill all fd with -1 so won't close incorrect
-		 * fd (fd=0 is stdin) when failure (zclose won't close
-		 * negative fd)).
-		 */
-		obj->maps[i].fd = -1;
-		obj->maps[i].inner_map_fd = -1;
-	}
-
-	/*
-	 * Fill obj->maps using data in "maps" section.
-	 */
-	for (i = 0, map_idx = 0; data && i < nr_syms; i++) {
+	/* Fill obj->maps using data in "maps" section.  */
+	for (i = 0; i < nr_syms; i++) {
 		GElf_Sym sym;
 		const char *map_name;
 		struct bpf_map_def *def;
+		struct bpf_map *map;
 
 		if (!gelf_getsym(symbols, i, &sym))
 			continue;
 		if (sym.st_shndx != obj->efile.maps_shndx)
 			continue;
 
-		map_name = elf_strptr(obj->efile.elf,
-				      obj->efile.strtabidx,
+		map = bpf_object__add_map(obj);
+		if (IS_ERR(map))
+			return PTR_ERR(map);
+
+		map_name = elf_strptr(obj->efile.elf, obj->efile.strtabidx,
 				      sym.st_name);
 		if (!map_name) {
 			pr_warning("failed to get map #%d name sym string for obj %s\n",
-				   map_idx, obj->path);
+				   i, obj->path);
 			return -LIBBPF_ERRNO__FORMAT;
 		}
 
-		obj->maps[map_idx].libbpf_type = LIBBPF_MAP_UNSPEC;
-		obj->maps[map_idx].offset = sym.st_value;
+		map->libbpf_type = LIBBPF_MAP_UNSPEC;
+		map->sec_idx = sym.st_shndx;
+		map->sec_offset = sym.st_value;
+		pr_debug("map '%s' (legacy): at sec_idx %d, offset %zu.\n",
+			 map_name, map->sec_idx, map->sec_offset);
 		if (sym.st_value + map_def_sz > data->d_size) {
 			pr_warning("corrupted maps section in %s: last map \"%s\" too small\n",
 				   obj->path, map_name);
 			return -EINVAL;
 		}
 
-		obj->maps[map_idx].name = strdup(map_name);
-		if (!obj->maps[map_idx].name) {
+		map->name = strdup(map_name);
+		if (!map->name) {
 			pr_warning("failed to alloc map name\n");
 			return -ENOMEM;
 		}
-		pr_debug("map %d is \"%s\"\n", map_idx,
-			 obj->maps[map_idx].name);
+		pr_debug("map %d is \"%s\"\n", i, map->name);
 		def = (struct bpf_map_def *)(data->d_buf + sym.st_value);
 		/*
 		 * If the definition of the map in the object file fits in
@@ -939,7 +983,7 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 		 * calloc above.
 		 */
 		if (map_def_sz <= sizeof(struct bpf_map_def)) {
-			memcpy(&obj->maps[map_idx].def, def, map_def_sz);
+			memcpy(&map->def, def, map_def_sz);
 		} else {
 			/*
 			 * Here the map structure being read is bigger than what
@@ -959,37 +1003,340 @@ static int bpf_object__init_maps(struct bpf_object *obj, int flags)
 						return -EINVAL;
 				}
 			}
-			memcpy(&obj->maps[map_idx].def, def,
-			       sizeof(struct bpf_map_def));
+			memcpy(&map->def, def, sizeof(struct bpf_map_def));
 		}
-		map_idx++;
 	}
+	return 0;
+}
 
-	if (!obj->caps.global_data)
-		goto finalize;
+static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf,
+						     __u32 id)
+{
+	const struct btf_type *t = btf__type_by_id(btf, id);
 
-	/*
-	 * Populate rest of obj->maps with libbpf internal maps.
-	 */
-	if (obj->efile.data_shndx >= 0)
-		ret = bpf_object__init_internal_map(obj, &obj->maps[map_idx++],
-						    LIBBPF_MAP_DATA,
-						    obj->efile.data,
-						    &obj->sections.data);
-	if (!ret && obj->efile.rodata_shndx >= 0)
-		ret = bpf_object__init_internal_map(obj, &obj->maps[map_idx++],
-						    LIBBPF_MAP_RODATA,
-						    obj->efile.rodata,
-						    &obj->sections.rodata);
-	if (!ret && obj->efile.bss_shndx >= 0)
-		ret = bpf_object__init_internal_map(obj, &obj->maps[map_idx++],
-						    LIBBPF_MAP_BSS,
-						    obj->efile.bss, NULL);
-finalize:
-	if (!ret)
+	while (true) {
+		switch (BTF_INFO_KIND(t->info)) {
+		case BTF_KIND_VOLATILE:
+		case BTF_KIND_CONST:
+		case BTF_KIND_RESTRICT:
+		case BTF_KIND_TYPEDEF:
+			t = btf__type_by_id(btf, t->type);
+			break;
+		default:
+			return t;
+		}
+	}
+}
+
+static bool get_map_field_int(const char *map_name,
+			      const struct btf *btf,
+			      const struct btf_type *def,
+			      const struct btf_member *m,
+			      const void *data, __u32 *res) {
+	const struct btf_type *t = skip_mods_and_typedefs(btf, m->type);
+	const char *name = btf__name_by_offset(btf, m->name_off);
+	__u32 int_info = *(const __u32 *)(const void *)(t + 1);
+
+	if (BTF_INFO_KIND(t->info) != BTF_KIND_INT) {
+		pr_warning("map '%s': attr '%s': expected INT, got %u.\n",
+			   map_name, name, BTF_INFO_KIND(t->info));
+		return false;
+	}
+	if (t->size != 4 || BTF_INT_BITS(int_info) != 32 ||
+	    BTF_INT_OFFSET(int_info)) {
+		pr_warning("map '%s': attr '%s': expected 32-bit non-bitfield integer, "
+			   "got %u-byte (%d-bit) one with bit offset %d.\n",
+			   map_name, name, t->size, BTF_INT_BITS(int_info),
+			   BTF_INT_OFFSET(int_info));
+		return false;
+	}
+	if (BTF_INFO_KFLAG(def->info) && BTF_MEMBER_BITFIELD_SIZE(m->offset)) {
+		pr_warning("map '%s': attr '%s': bitfield is not supported.\n",
+			   map_name, name);
+		return false;
+	}
+	if (m->offset % 32) {
+		pr_warning("map '%s': attr '%s': unaligned fields are not supported.\n",
+			   map_name, name);
+		return false;
+	}
+
+	*res = *(const __u32 *)(data + m->offset / 8);
+	return true;
+}
+
+static int bpf_object__init_user_btf_map(struct bpf_object *obj,
+					 const struct btf_type *sec,
+					 int var_idx, int sec_idx,
+					 const Elf_Data *data, bool strict)
+{
+	const struct btf_type *var, *def, *t;
+	const struct btf_var_secinfo *vi;
+	const struct btf_var *var_extra;
+	const struct btf_member *m;
+	const void *def_data;
+	const char *map_name;
+	struct bpf_map *map;
+	int vlen, i;
+
+	vi = (const struct btf_var_secinfo *)(const void *)(sec + 1) + var_idx;
+	var = btf__type_by_id(obj->btf, vi->type);
+	var_extra = (const void *)(var + 1);
+	map_name = btf__name_by_offset(obj->btf, var->name_off);
+	vlen = BTF_INFO_VLEN(var->info);
+
+	if (map_name == NULL || map_name[0] == '\0') {
+		pr_warning("map #%d: empty name.\n", var_idx);
+		return -EINVAL;
+	}
+	if ((__u64)vi->offset + vi->size > data->d_size) {
+		pr_warning("map '%s' BTF data is corrupted.\n", map_name);
+		return -EINVAL;
+	}
+	if (BTF_INFO_KIND(var->info) != BTF_KIND_VAR) {
+		pr_warning("map '%s': unexpected var kind %u.\n",
+			   map_name, BTF_INFO_KIND(var->info));
+		return -EINVAL;
+	}
+	if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED &&
+	    var_extra->linkage != BTF_VAR_STATIC) {
+		pr_warning("map '%s': unsupported var linkage %u.\n",
+			   map_name, var_extra->linkage);
+		return -EOPNOTSUPP;
+	}
+
+	def = skip_mods_and_typedefs(obj->btf, var->type);
+	if (BTF_INFO_KIND(def->info) != BTF_KIND_STRUCT) {
+		pr_warning("map '%s': unexpected def kind %u.\n",
+			   map_name, BTF_INFO_KIND(var->info));
+		return -EINVAL;
+	}
+	if (def->size > vi->size) {
+		pr_warning("map '%s': invalid def size.\n", map_name);
+		return -EINVAL;
+	}
+
+	map = bpf_object__add_map(obj);
+	if (IS_ERR(map))
+		return PTR_ERR(map);
+	map->name = strdup(map_name);
+	if (!map->name) {
+		pr_warning("map '%s': failed to alloc map name.\n", map_name);
+		return -ENOMEM;
+	}
+	map->libbpf_type = LIBBPF_MAP_UNSPEC;
+	map->def.type = BPF_MAP_TYPE_UNSPEC;
+	map->sec_idx = sec_idx;
+	map->sec_offset = vi->offset;
+	pr_debug("map '%s': at sec_idx %d, offset %zu.\n",
+		 map_name, map->sec_idx, map->sec_offset);
+
+	def_data = data->d_buf + vi->offset;
+	vlen = BTF_INFO_VLEN(def->info);
+	m = (const void *)(def + 1);
+	for (i = 0; i < vlen; i++, m++) {
+		const char *name = btf__name_by_offset(obj->btf, m->name_off);
+
+		if (!name) {
+			pr_warning("map '%s': invalid field #%d.\n",
+				   map_name, i);
+			return -EINVAL;
+		}
+		if (strcmp(name, "type") == 0) {
+			if (!get_map_field_int(map_name, obj->btf, def, m,
+					       def_data, &map->def.type))
+				return -EINVAL;
+			pr_debug("map '%s': found type = %u.\n",
+				 map_name, map->def.type);
+		} else if (strcmp(name, "max_entries") == 0) {
+			if (!get_map_field_int(map_name, obj->btf, def, m,
+					       def_data, &map->def.max_entries))
+				return -EINVAL;
+			pr_debug("map '%s': found max_entries = %u.\n",
+				 map_name, map->def.max_entries);
+		} else if (strcmp(name, "map_flags") == 0) {
+			if (!get_map_field_int(map_name, obj->btf, def, m,
+					       def_data, &map->def.map_flags))
+				return -EINVAL;
+			pr_debug("map '%s': found map_flags = %u.\n",
+				 map_name, map->def.map_flags);
+		} else if (strcmp(name, "key_size") == 0) {
+			__u32 sz;
+
+			if (!get_map_field_int(map_name, obj->btf, def, m,
+					       def_data, &sz))
+				return -EINVAL;
+			pr_debug("map '%s': found key_size = %u.\n",
+				 map_name, sz);
+			if (map->def.key_size && map->def.key_size != sz) {
+				pr_warning("map '%s': conflictling key size %u != %u.\n",
+					   map_name, map->def.key_size, sz);
+				return -EINVAL;
+			}
+			map->def.key_size = sz;
+		} else if (strcmp(name, "key") == 0) {
+			__s64 sz;
+
+			t = btf__type_by_id(obj->btf, m->type);
+			if (!t) {
+				pr_warning("map '%s': key type [%d] not found.\n",
+					   map_name, m->type);
+				return -EINVAL;
+			}
+			if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) {
+				pr_warning("map '%s': key spec is not PTR: %u.\n",
+					   map_name, BTF_INFO_KIND(t->info));
+				return -EINVAL;
+			}
+			sz = btf__resolve_size(obj->btf, t->type);
+			if (sz < 0) {
+				pr_warning("map '%s': can't determine key size for type [%u]: %lld.\n",
+					   map_name, t->type, sz);
+				return sz;
+			}
+			pr_debug("map '%s': found key [%u], sz = %lld.\n",
+				 map_name, t->type, sz);
+			if (map->def.key_size && map->def.key_size != sz) {
+				pr_warning("map '%s': conflictling key size %u != %lld.\n",
+					   map_name, map->def.key_size, sz);
+				return -EINVAL;
+			}
+			map->def.key_size = sz;
+			map->btf_key_type_id = t->type;
+		} else if (strcmp(name, "value_size") == 0) {
+			__u32 sz;
+
+			if (!get_map_field_int(map_name, obj->btf, def, m,
+					       def_data, &sz))
+				return -EINVAL;
+			pr_debug("map '%s': found value_size = %u.\n",
+				 map_name, sz);
+			if (map->def.value_size && map->def.value_size != sz) {
+				pr_warning("map '%s': conflictling value size %u != %u.\n",
+					   map_name, map->def.value_size, sz);
+				return -EINVAL;
+			}
+			map->def.value_size = sz;
+		} else if (strcmp(name, "value") == 0) {
+			__s64 sz;
+
+			t = btf__type_by_id(obj->btf, m->type);
+			if (!t) {
+				pr_warning("map '%s': value type [%d] not found.\n",
+					   map_name, m->type);
+				return -EINVAL;
+			}
+			if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) {
+				pr_warning("map '%s': value spec is not PTR: %u.\n",
+					   map_name, BTF_INFO_KIND(t->info));
+				return -EINVAL;
+			}
+			sz = btf__resolve_size(obj->btf, t->type);
+			if (sz < 0) {
+				pr_warning("map '%s': can't determine value size for type [%u]: %lld.\n",
+					   map_name, t->type, sz);
+				return sz;
+			}
+			pr_debug("map '%s': found value [%u], sz = %lld.\n",
+				 map_name, t->type, sz);
+			if (map->def.value_size && map->def.value_size != sz) {
+				pr_warning("map '%s': conflictling value size %u != %lld.\n",
+					   map_name, map->def.value_size, sz);
+				return -EINVAL;
+			}
+			map->def.value_size = sz;
+			map->btf_value_type_id = t->type;
+		} else {
+			if (strict) {
+				pr_warning("map '%s': unknown field '%s'.\n",
+					   map_name, name);
+				return -ENOTSUP;
+			}
+			pr_debug("map '%s': ignoring unknown field '%s'.\n",
+				 map_name, name);
+		}
+	}
+
+	if (map->def.type == BPF_MAP_TYPE_UNSPEC) {
+		pr_warning("map '%s': map type isn't specified.\n", map_name);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
+{
+	const struct btf_type *sec = NULL;
+	int nr_types, i, vlen, err;
+	const struct btf_type *t;
+	const char *name;
+	Elf_Data *data;
+	Elf_Scn *scn;
+
+	if (obj->efile.btf_maps_shndx < 0)
+		return 0;
+
+	scn = elf_getscn(obj->efile.elf, obj->efile.btf_maps_shndx);
+	if (scn)
+		data = elf_getdata(scn, NULL);
+	if (!scn || !data) {
+		pr_warning("failed to get Elf_Data from map section %d (%s)\n",
+			   obj->efile.maps_shndx, MAPS_ELF_SEC);
+		return -EINVAL;
+	}
+
+	nr_types = btf__get_nr_types(obj->btf);
+	for (i = 1; i <= nr_types; i++) {
+		t = btf__type_by_id(obj->btf, i);
+		if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC)
+			continue;
+		name = btf__name_by_offset(obj->btf, t->name_off);
+		if (strcmp(name, MAPS_ELF_SEC) == 0) {
+			sec = t;
+			break;
+		}
+	}
+
+	if (!sec) {
+		pr_warning("DATASEC '%s' not found.\n", MAPS_ELF_SEC);
+		return -ENOENT;
+	}
+
+	vlen = BTF_INFO_VLEN(sec->info);
+	for (i = 0; i < vlen; i++) {
+		err = bpf_object__init_user_btf_map(obj, sec, i,
+						    obj->efile.btf_maps_shndx,
+						    data, strict);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int bpf_object__init_maps(struct bpf_object *obj, int flags)
+{
+	bool strict = !(flags & MAPS_RELAX_COMPAT);
+	int err;
+
+	err = bpf_object__init_user_maps(obj, strict);
+	if (err)
+		return err;
+
+	err = bpf_object__init_user_btf_maps(obj, strict);
+	if (err)
+		return err;
+
+	err = bpf_object__init_global_data_maps(obj);
+	if (err)
+		return err;
+
+	if (obj->nr_maps) {
 		qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]),
 		      compare_bpf_map);
-	return ret;
+	}
+	return 0;
 }
 
 static bool section_have_execinstr(struct bpf_object *obj, int idx)
@@ -1078,6 +1425,86 @@ static void bpf_object__sanitize_btf_ext(struct bpf_object *obj)
 	}
 }
 
+static bool bpf_object__is_btf_mandatory(const struct bpf_object *obj)
+{
+	return obj->efile.btf_maps_shndx >= 0;
+}
+
+static int bpf_object__init_btf(struct bpf_object *obj,
+				Elf_Data *btf_data,
+				Elf_Data *btf_ext_data)
+{
+	bool btf_required = bpf_object__is_btf_mandatory(obj);
+	int err = 0;
+
+	if (btf_data) {
+		obj->btf = btf__new(btf_data->d_buf, btf_data->d_size);
+		if (IS_ERR(obj->btf)) {
+			pr_warning("Error loading ELF section %s: %d.\n",
+				   BTF_ELF_SEC, err);
+			goto out;
+		}
+		err = btf__finalize_data(obj, obj->btf);
+		if (err) {
+			pr_warning("Error finalizing %s: %d.\n",
+				   BTF_ELF_SEC, err);
+			goto out;
+		}
+	}
+	if (btf_ext_data) {
+		if (!obj->btf) {
+			pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n",
+				 BTF_EXT_ELF_SEC, BTF_ELF_SEC);
+			goto out;
+		}
+		obj->btf_ext = btf_ext__new(btf_ext_data->d_buf,
+					    btf_ext_data->d_size);
+		if (IS_ERR(obj->btf_ext)) {
+			pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n",
+				   BTF_EXT_ELF_SEC, PTR_ERR(obj->btf_ext));
+			obj->btf_ext = NULL;
+			goto out;
+		}
+	}
+out:
+	if (err || IS_ERR(obj->btf)) {
+		if (btf_required)
+			err = err ? : PTR_ERR(obj->btf);
+		else
+			err = 0;
+		if (!IS_ERR_OR_NULL(obj->btf))
+			btf__free(obj->btf);
+		obj->btf = NULL;
+	}
+	if (btf_required && !obj->btf) {
+		pr_warning("BTF is required, but is missing or corrupted.\n");
+		return err == 0 ? -ENOENT : err;
+	}
+	return 0;
+}
+
+static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
+{
+	int err = 0;
+
+	if (!obj->btf)
+		return 0;
+
+	bpf_object__sanitize_btf(obj);
+	bpf_object__sanitize_btf_ext(obj);
+
+	err = btf__load(obj->btf);
+	if (err) {
+		pr_warning("Error loading %s into kernel: %d.\n",
+			   BTF_ELF_SEC, err);
+		btf__free(obj->btf);
+		obj->btf = NULL;
+		if (bpf_object__is_btf_mandatory(obj))
+			return err;
+	}
+	return 0;
+}
+
 static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 {
 	Elf *elf = obj->efile.elf;
@@ -1102,24 +1529,21 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 		if (gelf_getshdr(scn, &sh) != &sh) {
 			pr_warning("failed to get section(%d) header from %s\n",
 				   idx, obj->path);
-			err = -LIBBPF_ERRNO__FORMAT;
-			goto out;
+			return -LIBBPF_ERRNO__FORMAT;
 		}
 
 		name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name);
 		if (!name) {
 			pr_warning("failed to get section(%d) name from %s\n",
 				   idx, obj->path);
-			err = -LIBBPF_ERRNO__FORMAT;
-			goto out;
+			return -LIBBPF_ERRNO__FORMAT;
 		}
 
 		data = elf_getdata(scn, 0);
 		if (!data) {
 			pr_warning("failed to get section(%d) data from %s(%s)\n",
 				   idx, name, obj->path);
-			err = -LIBBPF_ERRNO__FORMAT;
-			goto out;
+			return -LIBBPF_ERRNO__FORMAT;
 		}
 		pr_debug("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n",
 			 idx, name, (unsigned long)data->d_size,
@@ -1130,12 +1554,18 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 			err = bpf_object__init_license(obj,
 						       data->d_buf,
 						       data->d_size);
+			if (err)
+				return err;
 		} else if (strcmp(name, "version") == 0) {
 			err = bpf_object__init_kversion(obj,
 							data->d_buf,
 							data->d_size);
+			if (err)
+				return err;
 		} else if (strcmp(name, "maps") == 0) {
 			obj->efile.maps_shndx = idx;
+		} else if (strcmp(name, MAPS_ELF_SEC) == 0) {
+			obj->efile.btf_maps_shndx = idx;
 		} else if (strcmp(name, BTF_ELF_SEC) == 0) {
 			btf_data = data;
 		} else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) {
@@ -1144,11 +1574,10 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 			if (obj->efile.symbols) {
 				pr_warning("bpf: multiple SYMTAB in %s\n",
 					   obj->path);
-				err = -LIBBPF_ERRNO__FORMAT;
-			} else {
+				return -LIBBPF_ERRNO__FORMAT;
+			}
 			obj->efile.symbols = data;
 			obj->efile.strtabidx = sh.sh_link;
-			}
 		} else if (sh.sh_type == SHT_PROGBITS && data->d_size > 0) {
 			if (sh.sh_flags & SHF_EXECINSTR) {
 				if (strcmp(name, ".text") == 0)
@@ -1162,6 +1591,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 
 					pr_warning("failed to alloc program %s (%s): %s",
 						   name, obj->path, cp);
+					return err;
 				}
 			} else if (strcmp(name, ".data") == 0) {
 				obj->efile.data = data;
@@ -1173,8 +1603,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 				pr_debug("skip section(%d) %s\n", idx, name);
 			}
 		} else if (sh.sh_type == SHT_REL) {
+			int nr_reloc = obj->efile.nr_reloc;
 			void *reloc = obj->efile.reloc;
-			int nr_reloc = obj->efile.nr_reloc + 1;
 			int sec = sh.sh_info; /* points to other section */
 
 			/* Only do relo for section with exec instructions */
@@ -1184,79 +1614,37 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 				continue;
 			}
 
-			reloc = reallocarray(reloc, nr_reloc,
+			reloc = reallocarray(reloc, nr_reloc + 1,
 					     sizeof(*obj->efile.reloc));
 			if (!reloc) {
 				pr_warning("realloc failed\n");
-				err = -ENOMEM;
-			} else {
-				int n = nr_reloc - 1;
+				return -ENOMEM;
+			}
 
 			obj->efile.reloc = reloc;
-				obj->efile.nr_reloc = nr_reloc;
+			obj->efile.nr_reloc++;
 
-				obj->efile.reloc[n].shdr = sh;
-				obj->efile.reloc[n].data = data;
-			}
+			obj->efile.reloc[nr_reloc].shdr = sh;
+			obj->efile.reloc[nr_reloc].data = data;
 		} else if (sh.sh_type == SHT_NOBITS && strcmp(name, ".bss") == 0) {
 			obj->efile.bss = data;
 			obj->efile.bss_shndx = idx;
 		} else {
 			pr_debug("skip section(%d) %s\n", idx, name);
 		}
-		if (err)
-			goto out;
 	}
 
 	if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) {
 		pr_warning("Corrupted ELF file: index of strtab invalid\n");
 		return -LIBBPF_ERRNO__FORMAT;
 	}
-	if (btf_data) {
-		obj->btf = btf__new(btf_data->d_buf, btf_data->d_size);
-		if (IS_ERR(obj->btf)) {
-			pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n",
-				   BTF_ELF_SEC, PTR_ERR(obj->btf));
-			obj->btf = NULL;
-		} else {
-			err = btf__finalize_data(obj, obj->btf);
-			if (!err) {
-				bpf_object__sanitize_btf(obj);
-				err = btf__load(obj->btf);
-			}
-			if (err) {
-				pr_warning("Error finalizing and loading %s into kernel: %d. Ignored and continue.\n",
-					   BTF_ELF_SEC, err);
-				btf__free(obj->btf);
-				obj->btf = NULL;
-				err = 0;
-			}
-		}
-	}
-	if (btf_ext_data) {
-		if (!obj->btf) {
-			pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n",
-				 BTF_EXT_ELF_SEC, BTF_ELF_SEC);
-		} else {
-			obj->btf_ext = btf_ext__new(btf_ext_data->d_buf,
-						    btf_ext_data->d_size);
-			if (IS_ERR(obj->btf_ext)) {
-				pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n",
-					   BTF_EXT_ELF_SEC,
-					   PTR_ERR(obj->btf_ext));
-				obj->btf_ext = NULL;
-			} else {
-				bpf_object__sanitize_btf_ext(obj);
-			}
-		}
-	}
-	if (bpf_object__has_maps(obj)) {
+	err = bpf_object__init_btf(obj, btf_data, btf_ext_data);
+	if (!err)
 		err = bpf_object__init_maps(obj, flags);
-		if (err)
-			goto out;
-	}
+	if (!err)
+		err = bpf_object__sanitize_and_load_btf(obj);
+	if (!err)
 		err = bpf_object__init_prog_names(obj);
-out:
 	return err;
 }
 
@@ -1297,7 +1685,8 @@ static bool bpf_object__shndx_is_data(const struct bpf_object *obj,
 static bool bpf_object__shndx_is_maps(const struct bpf_object *obj,
 				      int shndx)
 {
-	return shndx == obj->efile.maps_shndx;
+	return shndx == obj->efile.maps_shndx ||
+	       shndx == obj->efile.btf_maps_shndx;
 }
 
 static bool bpf_object__relo_in_known_section(const struct bpf_object *obj,
@@ -1341,14 +1730,14 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 	prog->nr_reloc = nrels;
 
 	for (i = 0; i < nrels; i++) {
-		GElf_Sym sym;
-		GElf_Rel rel;
-		unsigned int insn_idx;
-		unsigned int shdr_idx;
 		struct bpf_insn *insns = prog->insns;
 		enum libbpf_map_type type;
+		unsigned int insn_idx;
+		unsigned int shdr_idx;
 		const char *name;
 		size_t map_idx;
+		GElf_Sym sym;
+		GElf_Rel rel;
 
 		if (!gelf_getrel(data, i, &rel)) {
 			pr_warning("relocation: failed to get %d reloc\n", i);
@@ -1416,9 +1805,13 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 				if (maps[map_idx].libbpf_type != type)
 					continue;
 				if (type != LIBBPF_MAP_UNSPEC ||
-				    maps[map_idx].offset == sym.st_value) {
-					pr_debug("relocation: find map %zd (%s) for insn %u\n",
-						 map_idx, maps[map_idx].name, insn_idx);
+				    (maps[map_idx].sec_idx == sym.st_shndx &&
+				     maps[map_idx].sec_offset == sym.st_value)) {
+					pr_debug("relocation: found map %zd (%s, sec_idx %d, offset %zu) for insn %u\n",
+						 map_idx, maps[map_idx].name,
+						 maps[map_idx].sec_idx,
+						 maps[map_idx].sec_offset,
+						 insn_idx);
 					break;
 				}
 			}
@@ -1438,14 +1831,18 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr,
 	return 0;
 }
 
-static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf)
+static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map)
 {
 	struct bpf_map_def *def = &map->def;
 	__u32 key_type_id = 0, value_type_id = 0;
 	int ret;
 
+	/* if it's BTF-defined map, we don't need to search for type IDs */
+	if (map->sec_idx == obj->efile.btf_maps_shndx)
+		return 0;
+
 	if (!bpf_map__is_internal(map)) {
-		ret = btf__get_map_kv_tids(btf, map->name, def->key_size,
+		ret = btf__get_map_kv_tids(obj->btf, map->name, def->key_size,
 					   def->value_size, &key_type_id,
 					   &value_type_id);
 	} else {
@@ -1453,7 +1850,7 @@ static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf)
 		 * LLVM annotates global data differently in BTF, that is,
 		 * only as '.data', '.bss' or '.rodata'.
 		 */
-		ret = btf__find_by_name(btf,
+		ret = btf__find_by_name(obj->btf,
 				libbpf_type_to_btf_name[map->libbpf_type]);
 	}
 	if (ret < 0)
@@ -1743,7 +2140,7 @@ bpf_object__create_maps(struct bpf_object *obj)
 		    map->inner_map_fd >= 0)
 			create_attr.inner_map_fd = map->inner_map_fd;
 
-		if (obj->btf && !bpf_map_find_btf_info(map, obj->btf)) {
+		if (obj->btf && !bpf_map_find_btf_info(obj, map)) {
 			create_attr.btf_fd = btf__fd(obj->btf);
 			create_attr.btf_key_type_id = map->btf_key_type_id;
 			create_attr.btf_value_type_id = map->btf_value_type_id;
@@ -3436,13 +3833,7 @@ bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name)
 struct bpf_map *
 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset)
 {
-	int i;
-
-	for (i = 0; i < obj->nr_maps; i++) {
-		if (obj->maps[i].offset == offset)
-			return &obj->maps[i];
-	}
-	return ERR_PTR(-ENOENT);
+	return ERR_PTR(-ENOTSUP);
 }
 
 long libbpf_get_error(const void *ptr)

tools/lib/bpf/libbpf_internal.h

@@ -23,6 +23,13 @@
 #define BTF_PARAM_ENC(name, type) (name), (type)
 #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
 
+#ifndef min
+# define min(x, y) ((x) < (y) ? (x) : (y))
+#endif
+#ifndef max
+# define max(x, y) ((x) < (y) ? (y) : (x))
+#endif
+
 extern void libbpf_print(enum libbpf_print_level level,
 			 const char *format, ...)
 	__attribute__((format(printf, 2, 3)));

tools/testing/selftests/bpf/progs/bpf_flow.c

@@ -57,17 +57,25 @@ struct frag_hdr {
 	__be32 identification;
 };
 
-struct bpf_map_def SEC("maps") jmp_table = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 key_size;
+	__u32 value_size;
+} jmp_table SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PROG_ARRAY,
+	.max_entries = 8,
 	.key_size = sizeof(__u32),
 	.value_size = sizeof(__u32),
-	.max_entries = 8
 };
 
-struct bpf_map_def SEC("maps") last_dissection = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct bpf_flow_keys *value;
+} last_dissection SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct bpf_flow_keys),
 	.max_entries = 1,
 };
 

tools/testing/selftests/bpf/progs/netcnt_prog.c

@@ -10,24 +10,22 @@
 #define REFRESH_TIME_NS	100000000
 #define NS_PER_SEC	1000000000
 
-struct bpf_map_def SEC("maps") percpu_netcnt = {
+struct {
+	__u32 type;
+	struct bpf_cgroup_storage_key *key;
+	struct percpu_net_cnt *value;
+} percpu_netcnt SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
-	.key_size = sizeof(struct bpf_cgroup_storage_key),
-	.value_size = sizeof(struct percpu_net_cnt),
 };
 
-BPF_ANNOTATE_KV_PAIR(percpu_netcnt, struct bpf_cgroup_storage_key,
-		     struct percpu_net_cnt);
-
-struct bpf_map_def SEC("maps") netcnt = {
+struct {
+	__u32 type;
+	struct bpf_cgroup_storage_key *key;
+	struct net_cnt *value;
+} netcnt SEC(".maps") = {
 	.type = BPF_MAP_TYPE_CGROUP_STORAGE,
-	.key_size = sizeof(struct bpf_cgroup_storage_key),
-	.value_size = sizeof(struct net_cnt),
 };
 
-BPF_ANNOTATE_KV_PAIR(netcnt, struct bpf_cgroup_storage_key,
-		     struct net_cnt);
-
 SEC("cgroup/skb")
 int bpf_nextcnt(struct __sk_buff *skb)
 {

tools/testing/selftests/bpf/progs/socket_cookie_prog.c

@@ -12,15 +12,16 @@ struct socket_cookie {
 	__u32 cookie_value;
 };
 
-struct bpf_map_def SEC("maps") socket_cookies = {
+struct {
+	__u32 type;
+	__u32 map_flags;
+	int *key;
+	struct socket_cookie *value;
+} socket_cookies SEC(".maps") = {
 	.type = BPF_MAP_TYPE_SK_STORAGE,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct socket_cookie),
 	.map_flags = BPF_F_NO_PREALLOC,
 };
 
-BPF_ANNOTATE_KV_PAIR(socket_cookies, int, struct socket_cookie);
-
 SEC("cgroup/connect6")
 int set_cookie(struct bpf_sock_addr *ctx)
 {

tools/testing/selftests/bpf/progs/test_btf_newkv.c

+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Facebook */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+int _version SEC("version") = 1;
+
+struct ipv_counts {
+	unsigned int v4;
+	unsigned int v6;
+};
+
+/* just to validate we can handle maps in multiple sections */
+struct bpf_map_def SEC("maps") btf_map_legacy = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(long long),
+	.max_entries = 4,
+};
+
+BPF_ANNOTATE_KV_PAIR(btf_map_legacy, int, struct ipv_counts);
+
+struct {
+	int *key;
+	struct ipv_counts *value;
+	unsigned int type;
+	unsigned int max_entries;
+} btf_map SEC(".maps") = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.max_entries = 4,
+};
+
+struct dummy_tracepoint_args {
+	unsigned long long pad;
+	struct sock *sock;
+};
+
+__attribute__((noinline))
+static int test_long_fname_2(struct dummy_tracepoint_args *arg)
+{
+	struct ipv_counts *counts;
+	int key = 0;
+
+	if (!arg->sock)
+		return 0;
+
+	counts = bpf_map_lookup_elem(&btf_map, &key);
+	if (!counts)
+		return 0;
+
+	counts->v6++;
+
+	/* just verify we can reference both maps */
+	counts = bpf_map_lookup_elem(&btf_map_legacy, &key);
+	if (!counts)
+		return 0;
+
+	return 0;
+}
+
+__attribute__((noinline))
+static int test_long_fname_1(struct dummy_tracepoint_args *arg)
+{
+	return test_long_fname_2(arg);
+}
+
+SEC("dummy_tracepoint")
+int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+{
+	return test_long_fname_1(arg);
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_get_stack_rawtp.c

@@ -15,17 +15,25 @@ struct stack_trace_t {
 	struct bpf_stack_build_id user_stack_buildid[MAX_STACK_RAWTP];
 };
 
-struct bpf_map_def SEC("maps") perfmap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 key_size;
+	__u32 value_size;
+} perfmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+	.max_entries = 2,
 	.key_size = sizeof(int),
 	.value_size = sizeof(__u32),
-	.max_entries = 2,
 };
 
-struct bpf_map_def SEC("maps") stackdata_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct stack_trace_t *value;
+} stackdata_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct stack_trace_t),
 	.max_entries = 1,
 };
 
@@ -47,10 +55,13 @@ struct bpf_map_def SEC("maps") stackdata_map = {
  * issue and avoid complicated C programming massaging.
  * This is an acceptable workaround since there is one entry here.
  */
-struct bpf_map_def SEC("maps") rawdata_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 (*value)[2 * MAX_STACK_RAWTP];
+} rawdata_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = MAX_STACK_RAWTP * sizeof(__u64) * 2,
 	.max_entries = 1,
 };
 

tools/testing/selftests/bpf/progs/test_global_data.c

@@ -7,17 +7,23 @@
 
 #include "bpf_helpers.h"
 
-struct bpf_map_def SEC("maps") result_number = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 *value;
+} result_number SEC(".maps") = {
 	.type		= BPF_MAP_TYPE_ARRAY,
-	.key_size	= sizeof(__u32),
-	.value_size	= sizeof(__u64),
 	.max_entries	= 11,
 };
 
-struct bpf_map_def SEC("maps") result_string = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	const char (*value)[32];
+} result_string SEC(".maps") = {
 	.type		= BPF_MAP_TYPE_ARRAY,
-	.key_size	= sizeof(__u32),
-	.value_size	= 32,
 	.max_entries	= 5,
 };
 
@@ -27,10 +33,13 @@ struct foo {
 	__u64 c;
 };
 
-struct bpf_map_def SEC("maps") result_struct = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct foo *value;
+} result_struct SEC(".maps") = {
 	.type		= BPF_MAP_TYPE_ARRAY,
-	.key_size	= sizeof(__u32),
-	.value_size	= sizeof(struct foo),
 	.max_entries	= 5,
 };
 

tools/testing/selftests/bpf/progs/test_l4lb.c

@@ -169,38 +169,53 @@ struct eth_hdr {
 	unsigned short eth_proto;
 };
 
-struct bpf_map_def SEC("maps") vip_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	struct vip *key;
+	struct vip_meta *value;
+} vip_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(struct vip),
-	.value_size = sizeof(struct vip_meta),
 	.max_entries = MAX_VIPS,
 };
 
-struct bpf_map_def SEC("maps") ch_rings = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} ch_rings SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = CH_RINGS_SIZE,
 };
 
-struct bpf_map_def SEC("maps") reals = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct real_definition *value;
+} reals SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct real_definition),
 	.max_entries = MAX_REALS,
 };
 
-struct bpf_map_def SEC("maps") stats = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct vip_stats *value;
+} stats SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct vip_stats),
 	.max_entries = MAX_VIPS,
 };
 
-struct bpf_map_def SEC("maps") ctl_array = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct ctl_value *value;
+} ctl_array SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct ctl_value),
 	.max_entries = CTL_MAP_SIZE,
 };
 

tools/testing/selftests/bpf/progs/test_l4lb_noinline.c

@@ -165,38 +165,53 @@ struct eth_hdr {
 	unsigned short eth_proto;
 };
 
-struct bpf_map_def SEC("maps") vip_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	struct vip *key;
+	struct vip_meta *value;
+} vip_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(struct vip),
-	.value_size = sizeof(struct vip_meta),
 	.max_entries = MAX_VIPS,
 };
 
-struct bpf_map_def SEC("maps") ch_rings = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} ch_rings SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = CH_RINGS_SIZE,
 };
 
-struct bpf_map_def SEC("maps") reals = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct real_definition *value;
+} reals SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct real_definition),
 	.max_entries = MAX_REALS,
 };
 
-struct bpf_map_def SEC("maps") stats = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct vip_stats *value;
+} stats SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct vip_stats),
 	.max_entries = MAX_VIPS,
 };
 
-struct bpf_map_def SEC("maps") ctl_array = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct ctl_value *value;
+} ctl_array SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct ctl_value),
 	.max_entries = CTL_MAP_SIZE,
 };
 

tools/testing/selftests/bpf/progs/test_map_lock.c

@@ -11,29 +11,31 @@ struct hmap_elem {
 	int var[VAR_NUM];
 };
 
-struct bpf_map_def SEC("maps") hash_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct hmap_elem *value;
+} hash_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct hmap_elem),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(hash_map, int, struct hmap_elem);
-
 struct array_elem {
 	struct bpf_spin_lock lock;
 	int var[VAR_NUM];
 };
 
-struct bpf_map_def SEC("maps") array_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	int *key;
+	struct array_elem *value;
+} array_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct array_elem),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(array_map, int, struct array_elem);
-
 SEC("map_lock_demo")
 int bpf_map_lock_test(struct __sk_buff *skb)
 {

tools/testing/selftests/bpf/progs/test_select_reuseport_kern.c

@@ -21,38 +21,55 @@ int _version SEC("version") = 1;
 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
 #endif
 
-struct bpf_map_def SEC("maps") outer_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 key_size;
+	__u32 value_size;
+} outer_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY_OF_MAPS,
+	.max_entries = 1,
 	.key_size = sizeof(__u32),
 	.value_size = sizeof(__u32),
-	.max_entries = 1,
 };
 
-struct bpf_map_def SEC("maps") result_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} result_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = NR_RESULTS,
 };
 
-struct bpf_map_def SEC("maps") tmp_index_ovr_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	int *value;
+} tmp_index_ovr_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(int),
 	.max_entries = 1,
 };
 
-struct bpf_map_def SEC("maps") linum_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} linum_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 1,
 };
 
-struct bpf_map_def SEC("maps") data_check_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct data_check *value;
+} data_check_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct data_check),
 	.max_entries = 1,
 };
 

tools/testing/selftests/bpf/progs/test_send_signal_kern.c

@@ -4,24 +4,26 @@
 #include <linux/version.h>
 #include "bpf_helpers.h"
 
-struct bpf_map_def SEC("maps") info_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 *value;
+} info_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u64),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(info_map, __u32, __u64);
-
-struct bpf_map_def SEC("maps") status_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 *value;
+} status_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u64),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(status_map, __u32, __u64);
-
 SEC("send_signal_demo")
 int bpf_send_signal_test(void *ctx)
 {

tools/testing/selftests/bpf/progs/test_sock_fields_kern.c

@@ -27,31 +27,43 @@ enum bpf_linum_array_idx {
 	__NR_BPF_LINUM_ARRAY_IDX,
 };
 
-struct bpf_map_def SEC("maps") addr_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct sockaddr_in6 *value;
+} addr_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct sockaddr_in6),
 	.max_entries = __NR_BPF_ADDR_ARRAY_IDX,
 };
 
-struct bpf_map_def SEC("maps") sock_result_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct bpf_sock *value;
+} sock_result_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct bpf_sock),
 	.max_entries = __NR_BPF_RESULT_ARRAY_IDX,
 };
 
-struct bpf_map_def SEC("maps") tcp_sock_result_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct bpf_tcp_sock *value;
+} tcp_sock_result_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct bpf_tcp_sock),
 	.max_entries = __NR_BPF_RESULT_ARRAY_IDX,
 };
 
-struct bpf_map_def SEC("maps") linum_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} linum_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = __NR_BPF_LINUM_ARRAY_IDX,
 };
 
@@ -60,26 +72,26 @@ struct bpf_spinlock_cnt {
 	__u32 cnt;
 };
 
-struct bpf_map_def SEC("maps") sk_pkt_out_cnt = {
+struct {
+	__u32 type;
+	__u32 map_flags;
+	int *key;
+	struct bpf_spinlock_cnt *value;
+} sk_pkt_out_cnt SEC(".maps") = {
 	.type = BPF_MAP_TYPE_SK_STORAGE,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct bpf_spinlock_cnt),
-	.max_entries = 0,
 	.map_flags = BPF_F_NO_PREALLOC,
 };
 
-BPF_ANNOTATE_KV_PAIR(sk_pkt_out_cnt, int, struct bpf_spinlock_cnt);
-
-struct bpf_map_def SEC("maps") sk_pkt_out_cnt10 = {
+struct {
+	__u32 type;
+	__u32 map_flags;
+	int *key;
+	struct bpf_spinlock_cnt *value;
+} sk_pkt_out_cnt10 SEC(".maps") = {
 	.type = BPF_MAP_TYPE_SK_STORAGE,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct bpf_spinlock_cnt),
-	.max_entries = 0,
 	.map_flags = BPF_F_NO_PREALLOC,
 };
 
-BPF_ANNOTATE_KV_PAIR(sk_pkt_out_cnt10, int, struct bpf_spinlock_cnt);
-
 static bool is_loopback6(__u32 *a6)
 {
 	return !a6[0] && !a6[1] && !a6[2] && a6[3] == bpf_htonl(1);

tools/testing/selftests/bpf/progs/test_spin_lock.c

@@ -10,30 +10,29 @@ struct hmap_elem {
 	int test_padding;
 };
 
-struct bpf_map_def SEC("maps") hmap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	int *key;
+	struct hmap_elem *value;
+} hmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct hmap_elem),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(hmap, int, struct hmap_elem);
-
-
 struct cls_elem {
 	struct bpf_spin_lock lock;
 	volatile int cnt;
 };
 
-struct bpf_map_def SEC("maps") cls_map = {
+struct {
+	__u32 type;
+	struct bpf_cgroup_storage_key *key;
+	struct cls_elem *value;
+} cls_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_CGROUP_STORAGE,
-	.key_size = sizeof(struct bpf_cgroup_storage_key),
-	.value_size = sizeof(struct cls_elem),
 };
 
-BPF_ANNOTATE_KV_PAIR(cls_map, struct bpf_cgroup_storage_key,
-		     struct cls_elem);
-
 struct bpf_vqueue {
 	struct bpf_spin_lock lock;
 	/* 4 byte hole */
@@ -42,14 +41,16 @@ struct bpf_vqueue {
 	unsigned int rate;
 };
 
-struct bpf_map_def SEC("maps") vqueue = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	int *key;
+	struct bpf_vqueue *value;
+} vqueue SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(int),
-	.value_size = sizeof(struct bpf_vqueue),
 	.max_entries = 1,
 };
 
-BPF_ANNOTATE_KV_PAIR(vqueue, int, struct bpf_vqueue);
 #define CREDIT_PER_NS(delta, rate) (((delta) * rate) >> 20)
 
 SEC("spin_lock_demo")

tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c

@@ -8,34 +8,50 @@
 #define PERF_MAX_STACK_DEPTH         127
 #endif
 
-struct bpf_map_def SEC("maps") control_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} control_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 1,
 };
 
-struct bpf_map_def SEC("maps") stackid_hmap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} stackid_hmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 16384,
 };
 
-struct bpf_map_def SEC("maps") stackmap = {
+typedef struct bpf_stack_build_id stack_trace_t[PERF_MAX_STACK_DEPTH];
+
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 map_flags;
+	__u32 key_size;
+	__u32 value_size;
+} stackmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_STACK_TRACE,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct bpf_stack_build_id)
-		* PERF_MAX_STACK_DEPTH,
 	.max_entries = 128,
 	.map_flags = BPF_F_STACK_BUILD_ID,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(stack_trace_t),
 };
 
-struct bpf_map_def SEC("maps") stack_amap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	/* there seems to be a bug in kernel not handling typedef properly */
+	struct bpf_stack_build_id (*value)[PERF_MAX_STACK_DEPTH];
+} stack_amap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct bpf_stack_build_id)
-		* PERF_MAX_STACK_DEPTH,
 	.max_entries = 128,
 };
 

tools/testing/selftests/bpf/progs/test_stacktrace_map.c

@@ -8,31 +8,47 @@
 #define PERF_MAX_STACK_DEPTH         127
 #endif
 
-struct bpf_map_def SEC("maps") control_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} control_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 1,
 };
 
-struct bpf_map_def SEC("maps") stackid_hmap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} stackid_hmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 16384,
 };
 
-struct bpf_map_def SEC("maps") stackmap = {
+typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
+
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 key_size;
+	__u32 value_size;
+} stackmap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_STACK_TRACE,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u64) * PERF_MAX_STACK_DEPTH,
 	.max_entries = 16384,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(stack_trace_t),
 };
 
-struct bpf_map_def SEC("maps") stack_amap = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 (*value)[PERF_MAX_STACK_DEPTH];
+} stack_amap SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u64) * PERF_MAX_STACK_DEPTH,
 	.max_entries = 16384,
 };
 

tools/testing/selftests/bpf/progs/test_tcp_estats.c

@@ -148,10 +148,13 @@ struct tcp_estats_basic_event {
 	struct tcp_estats_conn_id conn_id;
 };
 
-struct bpf_map_def SEC("maps") ev_record_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct tcp_estats_basic_event *value;
+} ev_record_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct tcp_estats_basic_event),
 	.max_entries = 1024,
 };
 

tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c

@@ -14,17 +14,23 @@
 #include "bpf_endian.h"
 #include "test_tcpbpf.h"
 
-struct bpf_map_def SEC("maps") global_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct tcpbpf_globals *value;
+} global_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct tcpbpf_globals),
 	.max_entries = 4,
 };
 
-struct bpf_map_def SEC("maps") sockopt_results = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	int *value;
+} sockopt_results SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(int),
 	.max_entries = 2,
 };
 

tools/testing/selftests/bpf/progs/test_tcpnotify_kern.c

@@ -14,18 +14,26 @@
 #include "bpf_endian.h"
 #include "test_tcpnotify.h"
 
-struct bpf_map_def SEC("maps") global_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct tcpnotify_globals *value;
+} global_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct tcpnotify_globals),
 	.max_entries = 4,
 };
 
-struct bpf_map_def SEC("maps") perf_event_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 key_size;
+	__u32 value_size;
+} perf_event_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+	.max_entries = 2,
 	.key_size = sizeof(int),
 	.value_size = sizeof(__u32),
-	.max_entries = 2,
 };
 
 int _version SEC("version") = 1;

tools/testing/selftests/bpf/progs/test_xdp.c

@@ -22,17 +22,23 @@
 
 int _version SEC("version") = 1;
 
-struct bpf_map_def SEC("maps") rxcnt = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u64 *value;
+} rxcnt SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u64),
 	.max_entries = 256,
 };
 
-struct bpf_map_def SEC("maps") vip2tnl = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	struct vip *key;
+	struct iptnl_info *value;
+} vip2tnl SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(struct vip),
-	.value_size = sizeof(struct iptnl_info),
 	.max_entries = MAX_IPTNL_ENTRIES,
 };
 

tools/testing/selftests/bpf/progs/test_xdp_noinline.c

@@ -163,52 +163,66 @@ struct lb_stats {
 	__u64 v1;
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) vip_map = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	struct vip_definition *key;
+	struct vip_meta *value;
+} vip_map SEC(".maps") = {
 	.type = BPF_MAP_TYPE_HASH,
-	.key_size = sizeof(struct vip_definition),
-	.value_size = sizeof(struct vip_meta),
 	.max_entries = 512,
-	.map_flags = 0,
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) lru_cache = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 map_flags;
+	struct flow_key *key;
+	struct real_pos_lru *value;
+} lru_cache SEC(".maps") = {
 	.type = BPF_MAP_TYPE_LRU_HASH,
-	.key_size = sizeof(struct flow_key),
-	.value_size = sizeof(struct real_pos_lru),
 	.max_entries = 300,
 	.map_flags = 1U << 1,
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) ch_rings = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	__u32 *value;
+} ch_rings SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(__u32),
 	.max_entries = 12 * 655,
-	.map_flags = 0,
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) reals = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct real_definition *value;
+} reals SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct real_definition),
 	.max_entries = 40,
-	.map_flags = 0,
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) stats = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct lb_stats *value;
+} stats SEC(".maps") = {
 	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct lb_stats),
 	.max_entries = 515,
-	.map_flags = 0,
 };
 
-struct bpf_map_def __attribute__ ((section("maps"), used)) ctl_array = {
+struct {
+	__u32 type;
+	__u32 max_entries;
+	__u32 *key;
+	struct ctl_value *value;
+} ctl_array SEC(".maps") = {
 	.type = BPF_MAP_TYPE_ARRAY,
-	.key_size = sizeof(__u32),
-	.value_size = sizeof(struct ctl_value),
 	.max_entries = 16,
-	.map_flags = 0,
 };
 
 struct eth_hdr {

tools/testing/selftests/bpf/test_btf.c

@@ -4016,13 +4016,9 @@ struct btf_file_test {
 };
 
 static struct btf_file_test file_tests[] = {
-{
-	.file = "test_btf_haskv.o",
-},
-{
-	.file = "test_btf_nokv.o",
-	.btf_kv_notfound = true,
-},
+	{ .file = "test_btf_haskv.o", },
+	{ .file = "test_btf_newkv.o", },
+	{ .file = "test_btf_nokv.o", .btf_kv_notfound = true, },
 };
 
 static int do_test_file(unsigned int test_num)