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-rw-r--r--tools/lib/bpf/bpf_helpers.h2
-rw-r--r--tools/lib/bpf/btf.c83
-rw-r--r--tools/lib/bpf/btf.h2
-rw-r--r--tools/lib/bpf/btf_dump.c39
-rw-r--r--tools/lib/bpf/libbpf.c34
-rw-r--r--tools/lib/bpf/libbpf.map2
6 files changed, 144 insertions, 18 deletions
diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h
index bc14db706b88..e9a4ecddb7a5 100644
--- a/tools/lib/bpf/bpf_helpers.h
+++ b/tools/lib/bpf/bpf_helpers.h
@@ -40,7 +40,7 @@
* Helper macro to manipulate data structures
*/
#ifndef offsetof
-#define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER)
+#define offsetof(TYPE, MEMBER) ((unsigned long)&((TYPE *)0)->MEMBER)
#endif
#ifndef container_of
#define container_of(ptr, type, member) \
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 4843e44916f7..7dfca7016aaa 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -41,6 +41,7 @@ struct btf {
__u32 types_size;
__u32 data_size;
int fd;
+ int ptr_sz;
};
static inline __u64 ptr_to_u64(const void *ptr)
@@ -221,6 +222,70 @@ const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id)
return btf->types[type_id];
}
+static int determine_ptr_size(const struct btf *btf)
+{
+ const struct btf_type *t;
+ const char *name;
+ int i;
+
+ for (i = 1; i <= btf->nr_types; i++) {
+ t = btf__type_by_id(btf, i);
+ if (!btf_is_int(t))
+ continue;
+
+ name = btf__name_by_offset(btf, t->name_off);
+ if (!name)
+ continue;
+
+ if (strcmp(name, "long int") == 0 ||
+ strcmp(name, "long unsigned int") == 0) {
+ if (t->size != 4 && t->size != 8)
+ continue;
+ return t->size;
+ }
+ }
+
+ return -1;
+}
+
+static size_t btf_ptr_sz(const struct btf *btf)
+{
+ if (!btf->ptr_sz)
+ ((struct btf *)btf)->ptr_sz = determine_ptr_size(btf);
+ return btf->ptr_sz < 0 ? sizeof(void *) : btf->ptr_sz;
+}
+
+/* Return pointer size this BTF instance assumes. The size is heuristically
+ * determined by looking for 'long' or 'unsigned long' integer type and
+ * recording its size in bytes. If BTF type information doesn't have any such
+ * type, this function returns 0. In the latter case, native architecture's
+ * pointer size is assumed, so will be either 4 or 8, depending on
+ * architecture that libbpf was compiled for. It's possible to override
+ * guessed value by using btf__set_pointer_size() API.
+ */
+size_t btf__pointer_size(const struct btf *btf)
+{
+ if (!btf->ptr_sz)
+ ((struct btf *)btf)->ptr_sz = determine_ptr_size(btf);
+
+ if (btf->ptr_sz < 0)
+ /* not enough BTF type info to guess */
+ return 0;
+
+ return btf->ptr_sz;
+}
+
+/* Override or set pointer size in bytes. Only values of 4 and 8 are
+ * supported.
+ */
+int btf__set_pointer_size(struct btf *btf, size_t ptr_sz)
+{
+ if (ptr_sz != 4 && ptr_sz != 8)
+ return -EINVAL;
+ btf->ptr_sz = ptr_sz;
+ return 0;
+}
+
static bool btf_type_is_void(const struct btf_type *t)
{
return t == &btf_void || btf_is_fwd(t);
@@ -253,7 +318,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
size = t->size;
goto done;
case BTF_KIND_PTR:
- size = sizeof(void *);
+ size = btf_ptr_sz(btf);
goto done;
case BTF_KIND_TYPEDEF:
case BTF_KIND_VOLATILE:
@@ -293,9 +358,9 @@ int btf__align_of(const struct btf *btf, __u32 id)
switch (kind) {
case BTF_KIND_INT:
case BTF_KIND_ENUM:
- return min(sizeof(void *), (size_t)t->size);
+ return min(btf_ptr_sz(btf), (size_t)t->size);
case BTF_KIND_PTR:
- return sizeof(void *);
+ return btf_ptr_sz(btf);
case BTF_KIND_TYPEDEF:
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
@@ -533,6 +598,18 @@ struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
if (IS_ERR(btf))
goto done;
+ switch (gelf_getclass(elf)) {
+ case ELFCLASS32:
+ btf__set_pointer_size(btf, 4);
+ break;
+ case ELFCLASS64:
+ btf__set_pointer_size(btf, 8);
+ break;
+ default:
+ pr_warn("failed to get ELF class (bitness) for %s\n", path);
+ break;
+ }
+
if (btf_ext && btf_ext_data) {
*btf_ext = btf_ext__new(btf_ext_data->d_buf,
btf_ext_data->d_size);
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index f4a1a1d2b9a3..1ca14448df4c 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -76,6 +76,8 @@ LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf,
LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf);
LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
__u32 id);
+LIBBPF_API size_t btf__pointer_size(const struct btf *btf);
+LIBBPF_API int btf__set_pointer_size(struct btf *btf, size_t ptr_sz);
LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index cf711168d34a..57c00fa63932 100644
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -13,6 +13,7 @@
#include <errno.h>
#include <linux/err.h>
#include <linux/btf.h>
+#include <linux/kernel.h>
#include "btf.h"
#include "hashmap.h"
#include "libbpf.h"
@@ -60,6 +61,7 @@ struct btf_dump {
const struct btf_ext *btf_ext;
btf_dump_printf_fn_t printf_fn;
struct btf_dump_opts opts;
+ int ptr_sz;
bool strip_mods;
/* per-type auxiliary state */
@@ -138,6 +140,7 @@ struct btf_dump *btf_dump__new(const struct btf *btf,
d->btf_ext = btf_ext;
d->printf_fn = printf_fn;
d->opts.ctx = opts ? opts->ctx : NULL;
+ d->ptr_sz = btf__pointer_size(btf) ? : sizeof(void *);
d->type_names = hashmap__new(str_hash_fn, str_equal_fn, NULL);
if (IS_ERR(d->type_names)) {
@@ -549,6 +552,9 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
}
}
+static void btf_dump_emit_missing_aliases(struct btf_dump *d, __u32 id,
+ const struct btf_type *t);
+
static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id,
const struct btf_type *t);
static void btf_dump_emit_struct_def(struct btf_dump *d, __u32 id,
@@ -671,6 +677,9 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
switch (kind) {
case BTF_KIND_INT:
+ /* Emit type alias definitions if necessary */
+ btf_dump_emit_missing_aliases(d, id, t);
+
tstate->emit_state = EMITTED;
break;
case BTF_KIND_ENUM:
@@ -797,7 +806,7 @@ static void btf_dump_emit_bit_padding(const struct btf_dump *d,
int align, int lvl)
{
int off_diff = m_off - cur_off;
- int ptr_bits = sizeof(void *) * 8;
+ int ptr_bits = d->ptr_sz * 8;
if (off_diff <= 0)
/* no gap */
@@ -870,7 +879,7 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
btf_dump_printf(d, ": %d", m_sz);
off = m_off + m_sz;
} else {
- m_sz = max(0, btf__resolve_size(d->btf, m->type));
+ m_sz = max((__s64)0, btf__resolve_size(d->btf, m->type));
off = m_off + m_sz * 8;
}
btf_dump_printf(d, ";");
@@ -890,6 +899,32 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
btf_dump_printf(d, " __attribute__((packed))");
}
+static const char *missing_base_types[][2] = {
+ /*
+ * GCC emits typedefs to its internal __PolyX_t types when compiling Arm
+ * SIMD intrinsics. Alias them to standard base types.
+ */
+ { "__Poly8_t", "unsigned char" },
+ { "__Poly16_t", "unsigned short" },
+ { "__Poly64_t", "unsigned long long" },
+ { "__Poly128_t", "unsigned __int128" },
+};
+
+static void btf_dump_emit_missing_aliases(struct btf_dump *d, __u32 id,
+ const struct btf_type *t)
+{
+ const char *name = btf_dump_type_name(d, id);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(missing_base_types); i++) {
+ if (strcmp(name, missing_base_types[i][0]) == 0) {
+ btf_dump_printf(d, "typedef %s %s;\n\n",
+ missing_base_types[i][1], name);
+ break;
+ }
+ }
+}
+
static void btf_dump_emit_enum_fwd(struct btf_dump *d, __u32 id,
const struct btf_type *t)
{
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 0a06124f7999..0ad0b0491e1f 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2264,7 +2264,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict,
data = elf_getdata(scn, NULL);
if (!scn || !data) {
pr_warn("failed to get Elf_Data from map section %d (%s)\n",
- obj->efile.maps_shndx, MAPS_ELF_SEC);
+ obj->efile.btf_maps_shndx, MAPS_ELF_SEC);
return -EINVAL;
}
@@ -2434,6 +2434,8 @@ static int bpf_object__init_btf(struct bpf_object *obj,
BTF_ELF_SEC, err);
goto out;
}
+ /* enforce 8-byte pointers for BPF-targeted BTFs */
+ btf__set_pointer_size(obj->btf, 8);
err = 0;
}
if (btf_ext_data) {
@@ -2542,6 +2544,8 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
if (IS_ERR(kern_btf))
return PTR_ERR(kern_btf);
+ /* enforce 8-byte pointers for BPF-targeted BTFs */
+ btf__set_pointer_size(obj->btf, 8);
bpf_object__sanitize_btf(obj, kern_btf);
}
@@ -3478,10 +3482,11 @@ bpf_object__probe_global_data(struct bpf_object *obj)
map = bpf_create_map_xattr(&map_attr);
if (map < 0) {
- cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
+ ret = -errno;
+ cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg));
pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n",
- __func__, cp, errno);
- return -errno;
+ __func__, cp, -ret);
+ return ret;
}
insns[0].imm = map;
@@ -5194,7 +5199,8 @@ static int bpf_object__collect_st_ops_relos(struct bpf_object *obj,
static int bpf_object__collect_map_relos(struct bpf_object *obj,
GElf_Shdr *shdr, Elf_Data *data)
{
- int i, j, nrels, new_sz, ptr_sz = sizeof(void *);
+ const int bpf_ptr_sz = 8, host_ptr_sz = sizeof(void *);
+ int i, j, nrels, new_sz;
const struct btf_var_secinfo *vi = NULL;
const struct btf_type *sec, *var, *def;
const struct btf_member *member;
@@ -5243,7 +5249,7 @@ static int bpf_object__collect_map_relos(struct bpf_object *obj,
vi = btf_var_secinfos(sec) + map->btf_var_idx;
if (vi->offset <= rel.r_offset &&
- rel.r_offset + sizeof(void *) <= vi->offset + vi->size)
+ rel.r_offset + bpf_ptr_sz <= vi->offset + vi->size)
break;
}
if (j == obj->nr_maps) {
@@ -5279,17 +5285,20 @@ static int bpf_object__collect_map_relos(struct bpf_object *obj,
return -EINVAL;
moff = rel.r_offset - vi->offset - moff;
- if (moff % ptr_sz)
+ /* here we use BPF pointer size, which is always 64 bit, as we
+ * are parsing ELF that was built for BPF target
+ */
+ if (moff % bpf_ptr_sz)
return -EINVAL;
- moff /= ptr_sz;
+ moff /= bpf_ptr_sz;
if (moff >= map->init_slots_sz) {
new_sz = moff + 1;
- tmp = realloc(map->init_slots, new_sz * ptr_sz);
+ tmp = realloc(map->init_slots, new_sz * host_ptr_sz);
if (!tmp)
return -ENOMEM;
map->init_slots = tmp;
memset(map->init_slots + map->init_slots_sz, 0,
- (new_sz - map->init_slots_sz) * ptr_sz);
+ (new_sz - map->init_slots_sz) * host_ptr_sz);
map->init_slots_sz = new_sz;
}
map->init_slots[moff] = targ_map;
@@ -6012,9 +6021,10 @@ int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
}
if (bpf_obj_pin(prog->instances.fds[instance], path)) {
- cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg));
+ err = -errno;
+ cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg));
pr_warn("failed to pin program: %s\n", cp);
- return -errno;
+ return err;
}
pr_debug("pinned program '%s'\n", path);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 0c4722bfdd0a..e35bd6cdbdbf 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -295,5 +295,7 @@ LIBBPF_0.1.0 {
bpf_program__set_sk_lookup;
btf__parse;
btf__parse_raw;
+ btf__pointer_size;
btf__set_fd;
+ btf__set_pointer_size;
} LIBBPF_0.0.9;
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-02 05:25:20 +0000