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Commit 726e333f authored by Alexei Starovoitov's avatar Alexei Starovoitov
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Merge branch 'compile-once-run-everywhere' 

Andrii Nakryiko says:

====================
This patch set implements central part of CO-RE (Compile Once - Run
Everywhere, see [0] and [1] for slides and video): relocating fields offsets.
Most of the details are written down as comments to corresponding parts of the
code.

Patch #1 adds a bunch of commonly useful btf_xxx helpers to simplify working
with BTF types.
Patch #2 converts existing libbpf code to these new helpers and removes some
of pre-existing ones.
Patch #3 adds loading of .BTF.ext offset relocations section and macros to
work with its contents.
Patch #4 implements CO-RE relocations algorithm in libbpf.
Patch #5 introduced BPF_CORE_READ macro, hiding usage of Clang's
__builtin_preserve_access_index intrinsic that records offset relocation.
Patches #6-#14 adds selftests validating various parts of relocation handling,
type compatibility, etc.

For all tests to work, you'll need latest Clang/LLVM supporting
__builtin_preserve_access_index intrinsic, used for recording offset
relocations. Kernel on which selftests run should have BTF information built
in (CONFIG_DEBUG_INFO_BTF=y).

  [0] http://vger.kernel.org/bpfconf2019.html#session-2
  [1] http://vger.kernel.org/lpc-bpf2018.html#session-2

v5->v6:
- fix bad comment formatting for real (Alexei);

v4->v5:
- drop constness for btf_xxx() helpers, allowing to avoid type casts (Alexei);
- rebase on latest bpf-next, change test__printf back to printf;

v3->v4:
- added btf_xxx helpers (Alexei);
- switched libbpf code to new helpers;
- reduced amount of logging and simplified format in few places (Alexei);
- made flavor name parsing logic more strict (exactly three underscores);
- no uname() error checking (Alexei);
- updated misc tests to reflect latest Clang fixes (Yonghong);

v2->v3:
- enclose BPF_CORE_READ args in parens (Song);

v1->v2:
- add offsetofend(), fix btf_ext optional fields checks (Song);
- add bpf_core_dump_spec() for logging spec representation;
- move special first element processing out of the loop (Song);
- typo fixes (Song);
- drop BPF_ST | BPF_MEM insn relocation (Alexei);
- extracted BPF_CORE_READ into bpf_helpers (Alexei);
- added extra tests validating Clang capturing relocs correctly (Yonghong);
- switch core_relocs.c to use sub-tests;
- updated mods tests after Clang bug was fixed (Yonghong);
- fix bug enumerating candidate types;
====================
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parents 682cdbdc 29e1c668
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Showing with 2981 additions and 281 deletions
tools/lib/bpf/btf.c
View file @ 726e333f
......@@ -19,13 +19,6 @@
#define BTF_MAX_NR_TYPES 0x7fffffff
#define BTF_MAX_STR_OFFSET 0x7fffffff
#define IS_MODIFIER(k) (((k) == BTF_KIND_TYPEDEF) || \
((k) == BTF_KIND_VOLATILE) || \
((k) == BTF_KIND_CONST) || \
((k) == BTF_KIND_RESTRICT))
#define IS_VAR(k) ((k) == BTF_KIND_VAR)
static struct btf_type btf_void;
struct btf {
......@@ -42,47 +35,6 @@ struct btf {
int fd;
};
struct btf_ext_info {
/*
* info points to the individual info section (e.g. func_info and
* line_info) from the .BTF.ext. It does not include the __u32 rec_size.
*/
void *info;
__u32 rec_size;
__u32 len;
};
struct btf_ext {
union {
struct btf_ext_header *hdr;
void *data;
};
struct btf_ext_info func_info;
struct btf_ext_info line_info;
__u32 data_size;
};
struct btf_ext_info_sec {
__u32 sec_name_off;
__u32 num_info;
/* Followed by num_info * record_size number of bytes */
__u8 data[0];
};
/* The minimum bpf_func_info checked by the loader */
struct bpf_func_info_min {
__u32 insn_off;
__u32 type_id;
};
/* The minimum bpf_line_info checked by the loader */
struct bpf_line_info_min {
__u32 insn_off;
__u32 file_name_off;
__u32 line_off;
__u32 line_col;
};
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
......@@ -192,9 +144,9 @@ static int btf_parse_str_sec(struct btf *btf)
static int btf_type_size(struct btf_type *t)
{
int base_size = sizeof(struct btf_type);
__u16 vlen = BTF_INFO_VLEN(t->info);
__u16 vlen = btf_vlen(t);
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_FWD:
case BTF_KIND_CONST:
case BTF_KIND_VOLATILE:
......@@ -219,7 +171,7 @@ static int btf_type_size(struct btf_type *t)
case BTF_KIND_DATASEC:
return base_size + vlen * sizeof(struct btf_var_secinfo);
default:
pr_debug("Unsupported BTF_KIND:%u\n", BTF_INFO_KIND(t->info));
pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t));
return -EINVAL;
}
}
......@@ -263,7 +215,7 @@ const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id)
static bool btf_type_is_void(const struct btf_type *t)
{
return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
return t == &btf_void || btf_is_fwd(t);
}
static bool btf_type_is_void_or_null(const struct btf_type *t)
......@@ -284,7 +236,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
t = btf__type_by_id(btf, type_id);
for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t);
i++) {
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_INT:
case BTF_KIND_STRUCT:
case BTF_KIND_UNION:
......@@ -303,7 +255,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
type_id = t->type;
break;
case BTF_KIND_ARRAY:
array = (const struct btf_array *)(t + 1);
array = btf_array(t);
if (nelems && array->nelems > UINT32_MAX / nelems)
return -E2BIG;
nelems *= array->nelems;
......@@ -334,8 +286,7 @@ int btf__resolve_type(const struct btf *btf, __u32 type_id)
t = btf__type_by_id(btf, type_id);
while (depth < MAX_RESOLVE_DEPTH &&
!btf_type_is_void_or_null(t) &&
(IS_MODIFIER(BTF_INFO_KIND(t->info)) ||
IS_VAR(BTF_INFO_KIND(t->info)))) {
(btf_is_mod(t) || btf_is_typedef(t) || btf_is_var(t))) {
type_id = t->type;
t = btf__type_by_id(btf, type_id);
depth++;
......@@ -554,11 +505,11 @@ static int compare_vsi_off(const void *_a, const void *_b)
static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
struct btf_type *t)
{
__u32 size = 0, off = 0, i, vars = BTF_INFO_VLEN(t->info);
__u32 size = 0, off = 0, i, vars = btf_vlen(t);
const char *name = btf__name_by_offset(btf, t->name_off);
const struct btf_type *t_var;
struct btf_var_secinfo *vsi;
struct btf_var *var;
const struct btf_var *var;
int ret;
if (!name) {
......@@ -574,12 +525,11 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
t->size = size;
for (i = 0, vsi = (struct btf_var_secinfo *)(t + 1);
i < vars; i++, vsi++) {
for (i = 0, vsi = btf_var_secinfos(t); i < vars; i++, vsi++) {
t_var = btf__type_by_id(btf, vsi->type);
var = (struct btf_var *)(t_var + 1);
var = btf_var(t_var);
if (BTF_INFO_KIND(t_var->info) != BTF_KIND_VAR) {
if (!btf_is_var(t_var)) {
pr_debug("Non-VAR type seen in section %s\n", name);
return -EINVAL;
}
......@@ -595,7 +545,8 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
ret = bpf_object__variable_offset(obj, name, &off);
if (ret) {
pr_debug("No offset found in symbol table for VAR %s\n", name);
pr_debug("No offset found in symbol table for VAR %s\n",
name);
return -ENOENT;
}
......@@ -619,7 +570,7 @@ int btf__finalize_data(struct bpf_object *obj, struct btf *btf)
* is section size and global variable offset. We use
* the info from the ELF itself for this purpose.
*/
if (BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC) {
if (btf_is_datasec(t)) {
err = btf_fixup_datasec(obj, btf, t);
if (err)
break;
......@@ -774,14 +725,13 @@ int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
return -EINVAL;
}
if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT ||
BTF_INFO_VLEN(container_type->info) < 2) {
if (!btf_is_struct(container_type) || btf_vlen(container_type) < 2) {
pr_warning("map:%s container_name:%s is an invalid container struct\n",
map_name, container_name);
return -EINVAL;
}
key = (struct btf_member *)(container_type + 1);
key = btf_members(container_type);
value = key + 1;
key_size = btf__resolve_size(btf, key->type);
......@@ -831,6 +781,9 @@ static int btf_ext_setup_info(struct btf_ext *btf_ext,
/* The start of the info sec (including the __u32 record_size). */
void *info;
if (ext_sec->len == 0)
return 0;
if (ext_sec->off & 0x03) {
pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n",
ext_sec->desc);
......@@ -934,11 +887,24 @@ static int btf_ext_setup_line_info(struct btf_ext *btf_ext)
return btf_ext_setup_info(btf_ext, &param);
}
static int btf_ext_setup_offset_reloc(struct btf_ext *btf_ext)
{
struct btf_ext_sec_setup_param param = {
.off = btf_ext->hdr->offset_reloc_off,
.len = btf_ext->hdr->offset_reloc_len,
.min_rec_size = sizeof(struct bpf_offset_reloc),
.ext_info = &btf_ext->offset_reloc_info,
.desc = "offset_reloc",
};
return btf_ext_setup_info(btf_ext, &param);
}
static int btf_ext_parse_hdr(__u8 *data, __u32 data_size)
{
const struct btf_ext_header *hdr = (struct btf_ext_header *)data;
if (data_size < offsetof(struct btf_ext_header, func_info_off) ||
if (data_size < offsetofend(struct btf_ext_header, hdr_len) ||
data_size < hdr->hdr_len) {
pr_debug("BTF.ext header not found");
return -EINVAL;
......@@ -996,6 +962,9 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size)
}
memcpy(btf_ext->data, data, size);
if (btf_ext->hdr->hdr_len <
offsetofend(struct btf_ext_header, line_info_len))
goto done;
err = btf_ext_setup_func_info(btf_ext);
if (err)
goto done;
......@@ -1004,6 +973,13 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size)
if (err)
goto done;
if (btf_ext->hdr->hdr_len <
offsetofend(struct btf_ext_header, offset_reloc_len))
goto done;
err = btf_ext_setup_offset_reloc(btf_ext);
if (err)
goto done;
done:
if (err) {
btf_ext__free(btf_ext);
......@@ -1440,10 +1416,9 @@ static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext,
d->map[0] = 0;
for (i = 1; i <= btf->nr_types; i++) {
struct btf_type *t = d->btf->types[i];
__u16 kind = BTF_INFO_KIND(t->info);
/* VAR and DATASEC are never deduped and are self-canonical */
if (kind == BTF_KIND_VAR || kind == BTF_KIND_DATASEC)
if (btf_is_var(t) || btf_is_datasec(t))
d->map[i] = i;
else
d->map[i] = BTF_UNPROCESSED_ID;
......@@ -1484,11 +1459,11 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
if (r)
return r;
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
struct btf_member *m = (struct btf_member *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_member *m = btf_members(t);
__u16 vlen = btf_vlen(t);
for (j = 0; j < vlen; j++) {
r = fn(&m->name_off, ctx);
......@@ -1499,8 +1474,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
break;
}
case BTF_KIND_ENUM: {
struct btf_enum *m = (struct btf_enum *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_enum *m = btf_enum(t);
__u16 vlen = btf_vlen(t);
for (j = 0; j < vlen; j++) {
r = fn(&m->name_off, ctx);
......@@ -1511,8 +1486,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
break;
}
case BTF_KIND_FUNC_PROTO: {
struct btf_param *m = (struct btf_param *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_param *m = btf_params(t);
__u16 vlen = btf_vlen(t);
for (j = 0; j < vlen; j++) {
r = fn(&m->name_off, ctx);
......@@ -1801,16 +1776,16 @@ static long btf_hash_enum(struct btf_type *t)
/* Check structural equality of two ENUMs. */
static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2)
{
struct btf_enum *m1, *m2;
const struct btf_enum *m1, *m2;
__u16 vlen;
int i;
if (!btf_equal_common(t1, t2))
return false;
vlen = BTF_INFO_VLEN(t1->info);
m1 = (struct btf_enum *)(t1 + 1);
m2 = (struct btf_enum *)(t2 + 1);
vlen = btf_vlen(t1);
m1 = btf_enum(t1);
m2 = btf_enum(t2);
for (i = 0; i < vlen; i++) {
if (m1->name_off != m2->name_off || m1->val != m2->val)
return false;
......@@ -1822,8 +1797,7 @@ static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2)
static inline bool btf_is_enum_fwd(struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM &&
BTF_INFO_VLEN(t->info) == 0;
return btf_is_enum(t) && btf_vlen(t) == 0;
}
static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
......@@ -1843,8 +1817,8 @@ static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
*/
static long btf_hash_struct(struct btf_type *t)
{
struct btf_member *member = (struct btf_member *)(t + 1);
__u32 vlen = BTF_INFO_VLEN(t->info);
const struct btf_member *member = btf_members(t);
__u32 vlen = btf_vlen(t);
long h = btf_hash_common(t);
int i;
......@@ -1864,16 +1838,16 @@ static long btf_hash_struct(struct btf_type *t)
*/
static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2)
{
struct btf_member *m1, *m2;
const struct btf_member *m1, *m2;
__u16 vlen;
int i;
if (!btf_equal_common(t1, t2))
return false;
vlen = BTF_INFO_VLEN(t1->info);
m1 = (struct btf_member *)(t1 + 1);
m2 = (struct btf_member *)(t2 + 1);
vlen = btf_vlen(t1);
m1 = btf_members(t1);
m2 = btf_members(t2);
for (i = 0; i < vlen; i++) {
if (m1->name_off != m2->name_off || m1->offset != m2->offset)
return false;
......@@ -1890,7 +1864,7 @@ static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2)
*/
static long btf_hash_array(struct btf_type *t)
{
struct btf_array *info = (struct btf_array *)(t + 1);
const struct btf_array *info = btf_array(t);
long h = btf_hash_common(t);
h = hash_combine(h, info->type);
......@@ -1908,13 +1882,13 @@ static long btf_hash_array(struct btf_type *t)
*/
static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2)
{
struct btf_array *info1, *info2;
const struct btf_array *info1, *info2;
if (!btf_equal_common(t1, t2))
return false;
info1 = (struct btf_array *)(t1 + 1);
info2 = (struct btf_array *)(t2 + 1);
info1 = btf_array(t1);
info2 = btf_array(t2);
return info1->type == info2->type &&
info1->index_type == info2->index_type &&
info1->nelems == info2->nelems;
......@@ -1927,14 +1901,10 @@ static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2)
*/
static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2)
{
struct btf_array *info1, *info2;
if (!btf_equal_common(t1, t2))
return false;
info1 = (struct btf_array *)(t1 + 1);
info2 = (struct btf_array *)(t2 + 1);
return info1->nelems == info2->nelems;
return btf_array(t1)->nelems == btf_array(t2)->nelems;
}
/*
......@@ -1944,8 +1914,8 @@ static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2)
*/
static long btf_hash_fnproto(struct btf_type *t)
{
struct btf_param *member = (struct btf_param *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
const struct btf_param *member = btf_params(t);
__u16 vlen = btf_vlen(t);
long h = btf_hash_common(t);
int i;
......@@ -1966,16 +1936,16 @@ static long btf_hash_fnproto(struct btf_type *t)
*/
static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
{
struct btf_param *m1, *m2;
const struct btf_param *m1, *m2;
__u16 vlen;
int i;
if (!btf_equal_common(t1, t2))
return false;
vlen = BTF_INFO_VLEN(t1->info);
m1 = (struct btf_param *)(t1 + 1);
m2 = (struct btf_param *)(t2 + 1);
vlen = btf_vlen(t1);
m1 = btf_params(t1);
m2 = btf_params(t2);
for (i = 0; i < vlen; i++) {
if (m1->name_off != m2->name_off || m1->type != m2->type)
return false;
......@@ -1992,7 +1962,7 @@ static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
*/
static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
{
struct btf_param *m1, *m2;
const struct btf_param *m1, *m2;
__u16 vlen;
int i;
......@@ -2000,9 +1970,9 @@ static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
if (t1->name_off != t2->name_off || t1->info != t2->info)
return false;
vlen = BTF_INFO_VLEN(t1->info);
m1 = (struct btf_param *)(t1 + 1);
m2 = (struct btf_param *)(t2 + 1);
vlen = btf_vlen(t1);
m1 = btf_params(t1);
m2 = btf_params(t2);
for (i = 0; i < vlen; i++) {
if (m1->name_off != m2->name_off)
return false;
......@@ -2028,7 +1998,7 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
__u32 cand_id;
long h;
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_CONST:
case BTF_KIND_VOLATILE:
case BTF_KIND_RESTRICT:
......@@ -2141,13 +2111,13 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id)
{
__u32 orig_type_id = type_id;
if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD)
if (!btf_is_fwd(d->btf->types[type_id]))
return type_id;
while (is_type_mapped(d, type_id) && d->map[type_id] != type_id)
type_id = d->map[type_id];
if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD)
if (!btf_is_fwd(d->btf->types[type_id]))
return type_id;
return orig_type_id;
......@@ -2156,7 +2126,7 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id)
static inline __u16 btf_fwd_kind(struct btf_type *t)
{
return BTF_INFO_KFLAG(t->info) ? BTF_KIND_UNION : BTF_KIND_STRUCT;
return btf_kflag(t) ? BTF_KIND_UNION : BTF_KIND_STRUCT;
}
/*
......@@ -2277,8 +2247,8 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
cand_type = d->btf->types[cand_id];
canon_type = d->btf->types[canon_id];
cand_kind = BTF_INFO_KIND(cand_type->info);
canon_kind = BTF_INFO_KIND(canon_type->info);
cand_kind = btf_kind(cand_type);
canon_kind = btf_kind(canon_type);
if (cand_type->name_off != canon_type->name_off)
return 0;
......@@ -2327,12 +2297,12 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
return btf_dedup_is_equiv(d, cand_type->type, canon_type->type);
case BTF_KIND_ARRAY: {
struct btf_array *cand_arr, *canon_arr;
const struct btf_array *cand_arr, *canon_arr;
if (!btf_compat_array(cand_type, canon_type))
return 0;
cand_arr = (struct btf_array *)(cand_type + 1);
canon_arr = (struct btf_array *)(canon_type + 1);
cand_arr = btf_array(cand_type);
canon_arr = btf_array(canon_type);
eq = btf_dedup_is_equiv(d,
cand_arr->index_type, canon_arr->index_type);
if (eq <= 0)
......@@ -2342,14 +2312,14 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
struct btf_member *cand_m, *canon_m;
const struct btf_member *cand_m, *canon_m;
__u16 vlen;
if (!btf_shallow_equal_struct(cand_type, canon_type))
return 0;
vlen = BTF_INFO_VLEN(cand_type->info);
cand_m = (struct btf_member *)(cand_type + 1);
canon_m = (struct btf_member *)(canon_type + 1);
vlen = btf_vlen(cand_type);
cand_m = btf_members(cand_type);
canon_m = btf_members(canon_type);
for (i = 0; i < vlen; i++) {
eq = btf_dedup_is_equiv(d, cand_m->type, canon_m->type);
if (eq <= 0)
......@@ -2362,7 +2332,7 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
}
case BTF_KIND_FUNC_PROTO: {
struct btf_param *cand_p, *canon_p;
const struct btf_param *cand_p, *canon_p;
__u16 vlen;
if (!btf_compat_fnproto(cand_type, canon_type))
......@@ -2370,9 +2340,9 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
eq = btf_dedup_is_equiv(d, cand_type->type, canon_type->type);
if (eq <= 0)
return eq;
vlen = BTF_INFO_VLEN(cand_type->info);
cand_p = (struct btf_param *)(cand_type + 1);
canon_p = (struct btf_param *)(canon_type + 1);
vlen = btf_vlen(cand_type);
cand_p = btf_params(cand_type);
canon_p = btf_params(canon_type);
for (i = 0; i < vlen; i++) {
eq = btf_dedup_is_equiv(d, cand_p->type, canon_p->type);
if (eq <= 0)
......@@ -2427,8 +2397,8 @@ static void btf_dedup_merge_hypot_map(struct btf_dedup *d)
targ_type_id = d->hypot_map[cand_type_id];
t_id = resolve_type_id(d, targ_type_id);
c_id = resolve_type_id(d, cand_type_id);
t_kind = BTF_INFO_KIND(d->btf->types[t_id]->info);
c_kind = BTF_INFO_KIND(d->btf->types[c_id]->info);
t_kind = btf_kind(d->btf->types[t_id]);
c_kind = btf_kind(d->btf->types[c_id]);
/*
* Resolve FWD into STRUCT/UNION.
* It's ok to resolve FWD into STRUCT/UNION that's not yet
......@@ -2497,7 +2467,7 @@ static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id)
return 0;
t = d->btf->types[type_id];
kind = BTF_INFO_KIND(t->info);
kind = btf_kind(t);
if (kind != BTF_KIND_STRUCT && kind != BTF_KIND_UNION)
return 0;
......@@ -2592,7 +2562,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
t = d->btf->types[type_id];
d->map[type_id] = BTF_IN_PROGRESS_ID;
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_CONST:
case BTF_KIND_VOLATILE:
case BTF_KIND_RESTRICT:
......@@ -2616,7 +2586,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
break;
case BTF_KIND_ARRAY: {
struct btf_array *info = (struct btf_array *)(t + 1);
struct btf_array *info = btf_array(t);
ref_type_id = btf_dedup_ref_type(d, info->type);
if (ref_type_id < 0)
......@@ -2650,8 +2620,8 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
return ref_type_id;
t->type = ref_type_id;
vlen = BTF_INFO_VLEN(t->info);
param = (struct btf_param *)(t + 1);
vlen = btf_vlen(t);
param = btf_params(t);
for (i = 0; i < vlen; i++) {
ref_type_id = btf_dedup_ref_type(d, param->type);
if (ref_type_id < 0)
......@@ -2791,7 +2761,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
struct btf_type *t = d->btf->types[type_id];
int i, r;
switch (BTF_INFO_KIND(t->info)) {
switch (btf_kind(t)) {
case BTF_KIND_INT:
case BTF_KIND_ENUM:
break;
......@@ -2811,7 +2781,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
break;
case BTF_KIND_ARRAY: {
struct btf_array *arr_info = (struct btf_array *)(t + 1);
struct btf_array *arr_info = btf_array(t);
r = btf_dedup_remap_type_id(d, arr_info->type);
if (r < 0)
......@@ -2826,8 +2796,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
struct btf_member *member = (struct btf_member *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_member *member = btf_members(t);
__u16 vlen = btf_vlen(t);
for (i = 0; i < vlen; i++) {
r = btf_dedup_remap_type_id(d, member->type);
......@@ -2840,8 +2810,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
}
case BTF_KIND_FUNC_PROTO: {
struct btf_param *param = (struct btf_param *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_param *param = btf_params(t);
__u16 vlen = btf_vlen(t);
r = btf_dedup_remap_type_id(d, t->type);
if (r < 0)
......@@ -2859,8 +2829,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
}
case BTF_KIND_DATASEC: {
struct btf_var_secinfo *var = (struct btf_var_secinfo *)(t + 1);
__u16 vlen = BTF_INFO_VLEN(t->info);
struct btf_var_secinfo *var = btf_var_secinfos(t);
__u16 vlen = btf_vlen(t);
for (i = 0; i < vlen; i++) {
r = btf_dedup_remap_type_id(d, var->type);
......
tools/lib/bpf/btf.h
View file @ 726e333f
......@@ -5,6 +5,7 @@
#define __LIBBPF_BTF_H
#include <stdarg.h>
#include <linux/btf.h>
#include <linux/types.h>
#ifdef __cplusplus
......@@ -57,6 +58,10 @@ struct btf_ext_header {
__u32 func_info_len;
__u32 line_info_off;
__u32 line_info_len;
/* optional part of .BTF.ext header */
__u32 offset_reloc_off;
__u32 offset_reloc_len;
};
LIBBPF_API void btf__free(struct btf *btf);
......@@ -120,6 +125,183 @@ LIBBPF_API void btf_dump__free(struct btf_dump *d);
LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
/*
* A set of helpers for easier BTF types handling
*/
static inline __u16 btf_kind(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info);
}
static inline __u16 btf_vlen(const struct btf_type *t)
{
return BTF_INFO_VLEN(t->info);
}
static inline bool btf_kflag(const struct btf_type *t)
{
return BTF_INFO_KFLAG(t->info);
}
static inline bool btf_is_int(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_INT;
}
static inline bool btf_is_ptr(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_PTR;
}
static inline bool btf_is_array(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_ARRAY;
}
static inline bool btf_is_struct(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_STRUCT;
}
static inline bool btf_is_union(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_UNION;
}
static inline bool btf_is_composite(const struct btf_type *t)
{
__u16 kind = btf_kind(t);
return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}
static inline bool btf_is_enum(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_ENUM;
}
static inline bool btf_is_fwd(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_FWD;
}
static inline bool btf_is_typedef(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_TYPEDEF;
}
static inline bool btf_is_volatile(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_VOLATILE;
}
static inline bool btf_is_const(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_CONST;
}
static inline bool btf_is_restrict(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_RESTRICT;
}
static inline bool btf_is_mod(const struct btf_type *t)
{
__u16 kind = btf_kind(t);
return kind == BTF_KIND_VOLATILE ||
kind == BTF_KIND_CONST ||
kind == BTF_KIND_RESTRICT;
}
static inline bool btf_is_func(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_FUNC;
}
static inline bool btf_is_func_proto(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_FUNC_PROTO;
}
static inline bool btf_is_var(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_VAR;
}
static inline bool btf_is_datasec(const struct btf_type *t)
{
return btf_kind(t) == BTF_KIND_DATASEC;
}
static inline __u8 btf_int_encoding(const struct btf_type *t)
{
return BTF_INT_ENCODING(*(__u32 *)(t + 1));
}
static inline __u8 btf_int_offset(const struct btf_type *t)
{
return BTF_INT_OFFSET(*(__u32 *)(t + 1));
}
static inline __u8 btf_int_bits(const struct btf_type *t)
{
return BTF_INT_BITS(*(__u32 *)(t + 1));
}
static inline struct btf_array *btf_array(const struct btf_type *t)
{
return (struct btf_array *)(t + 1);
}
static inline struct btf_enum *btf_enum(const struct btf_type *t)
{
return (struct btf_enum *)(t + 1);
}
static inline struct btf_member *btf_members(const struct btf_type *t)
{
return (struct btf_member *)(t + 1);
}
/* Get bit offset of a member with specified index. */
static inline __u32 btf_member_bit_offset(const struct btf_type *t,
__u32 member_idx)
{
const struct btf_member *m = btf_members(t) + member_idx;
bool kflag = btf_kflag(t);
return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
}
/*
* Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
* BTF_KIND_UNION. If member is not a bitfield, zero is returned.
*/
static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
__u32 member_idx)
{
const struct btf_member *m = btf_members(t) + member_idx;
bool kflag = btf_kflag(t);
return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
}
static inline struct btf_param *btf_params(const struct btf_type *t)
{
return (struct btf_param *)(t + 1);
}
static inline struct btf_var *btf_var(const struct btf_type *t)
{
return (struct btf_var *)(t + 1);
}
static inline struct btf_var_secinfo *
btf_var_secinfos(const struct btf_type *t)
{
return (struct btf_var_secinfo *)(t + 1);
}
#ifdef __cplusplus
} /* extern "C" */
#endif
......
tools/lib/bpf/btf_dump.c
View file @ 726e333f
......@@ -100,21 +100,6 @@ static bool str_equal_fn(const void *a, const void *b, void *ctx)
return strcmp(a, b) == 0;
}
static __u16 btf_kind_of(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info);
}
static __u16 btf_vlen_of(const struct btf_type *t)
{
return BTF_INFO_VLEN(t->info);
}
static bool btf_kflag_of(const struct btf_type *t)
{
return BTF_INFO_KFLAG(t->info);
}
static const char *btf_name_of(const struct btf_dump *d, __u32 name_off)
{
return btf__name_by_offset(d->btf, name_off);
......@@ -349,7 +334,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
*/
struct btf_dump_type_aux_state *tstate = &d->type_states[id];
const struct btf_type *t;
__u16 kind, vlen;
__u16 vlen;
int err, i;
/* return true, letting typedefs know that it's ok to be emitted */
......@@ -357,18 +342,16 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
return 1;
t = btf__type_by_id(d->btf, id);
kind = btf_kind_of(t);
if (tstate->order_state == ORDERING) {
/* type loop, but resolvable through fwd declaration */
if ((kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION) &&
through_ptr && t->name_off != 0)
if (btf_is_composite(t) && through_ptr && t->name_off != 0)
return 0;
pr_warning("unsatisfiable type cycle, id:[%u]\n", id);
return -ELOOP;
}
switch (kind) {
switch (btf_kind(t)) {
case BTF_KIND_INT:
tstate->order_state = ORDERED;
return 0;
......@@ -378,14 +361,12 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
tstate->order_state = ORDERED;
return err;
case BTF_KIND_ARRAY: {
const struct btf_array *a = (void *)(t + 1);
case BTF_KIND_ARRAY:
return btf_dump_order_type(d, btf_array(t)->type, through_ptr);
return btf_dump_order_type(d, a->type, through_ptr);
}
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
const struct btf_member *m = (void *)(t + 1);
const struct btf_member *m = btf_members(t);
/*
* struct/union is part of strong link, only if it's embedded
* (so no ptr in a path) or it's anonymous (so has to be
......@@ -396,7 +377,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
tstate->order_state = ORDERING;
vlen = btf_vlen_of(t);
vlen = btf_vlen(t);
for (i = 0; i < vlen; i++, m++) {
err = btf_dump_order_type(d, m->type, false);
if (err < 0)
......@@ -447,7 +428,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
return btf_dump_order_type(d, t->type, through_ptr);
case BTF_KIND_FUNC_PROTO: {
const struct btf_param *p = (void *)(t + 1);
const struct btf_param *p = btf_params(t);
bool is_strong;
err = btf_dump_order_type(d, t->type, through_ptr);
......@@ -455,7 +436,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
return err;
is_strong = err > 0;
vlen = btf_vlen_of(t);
vlen = btf_vlen(t);
for (i = 0; i < vlen; i++, p++) {
err = btf_dump_order_type(d, p->type, through_ptr);
if (err < 0)
......@@ -553,7 +534,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
return;
t = btf__type_by_id(d->btf, id);
kind = btf_kind_of(t);
kind = btf_kind(t);
if (top_level_def && t->name_off == 0) {
pr_warning("unexpected nameless definition, id:[%u]\n", id);
......@@ -618,12 +599,9 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
case BTF_KIND_RESTRICT:
btf_dump_emit_type(d, t->type, cont_id);
break;
case BTF_KIND_ARRAY: {
const struct btf_array *a = (void *)(t + 1);
btf_dump_emit_type(d, a->type, cont_id);
case BTF_KIND_ARRAY:
btf_dump_emit_type(d, btf_array(t)->type, cont_id);
break;
}
case BTF_KIND_FWD:
btf_dump_emit_fwd_def(d, id, t);
btf_dump_printf(d, ";\n\n");
......@@ -656,8 +634,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
* applicable
*/
if (top_level_def || t->name_off == 0) {
const struct btf_member *m = (void *)(t + 1);
__u16 vlen = btf_vlen_of(t);
const struct btf_member *m = btf_members(t);
__u16 vlen = btf_vlen(t);
int i, new_cont_id;
new_cont_id = t->name_off == 0 ? cont_id : id;
......@@ -678,8 +656,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
}
break;
case BTF_KIND_FUNC_PROTO: {
const struct btf_param *p = (void *)(t + 1);
__u16 vlen = btf_vlen_of(t);
const struct btf_param *p = btf_params(t);
__u16 vlen = btf_vlen(t);
int i;
btf_dump_emit_type(d, t->type, cont_id);
......@@ -696,7 +674,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
static int btf_align_of(const struct btf *btf, __u32 id)
{
const struct btf_type *t = btf__type_by_id(btf, id);
__u16 kind = btf_kind_of(t);
__u16 kind = btf_kind(t);
switch (kind) {
case BTF_KIND_INT:
......@@ -709,15 +687,12 @@ static int btf_align_of(const struct btf *btf, __u32 id)
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
return btf_align_of(btf, t->type);
case BTF_KIND_ARRAY: {
const struct btf_array *a = (void *)(t + 1);
return btf_align_of(btf, a->type);
}
case BTF_KIND_ARRAY:
return btf_align_of(btf, btf_array(t)->type);
case BTF_KIND_STRUCT:
case BTF_KIND_UNION: {
const struct btf_member *m = (void *)(t + 1);
__u16 vlen = btf_vlen_of(t);
const struct btf_member *m = btf_members(t);
__u16 vlen = btf_vlen(t);
int i, align = 1;
for (i = 0; i < vlen; i++, m++)
......@@ -726,7 +701,7 @@ static int btf_align_of(const struct btf *btf, __u32 id)
return align;
}
default:
pr_warning("unsupported BTF_KIND:%u\n", btf_kind_of(t));
pr_warning("unsupported BTF_KIND:%u\n", btf_kind(t));
return 1;
}
}
......@@ -737,20 +712,18 @@ static bool btf_is_struct_packed(const struct btf *btf, __u32 id,
const struct btf_member *m;
int align, i, bit_sz;
__u16 vlen;
bool kflag;
align = btf_align_of(btf, id);
/* size of a non-packed struct has to be a multiple of its alignment*/
if (t->size % align)
return true;
m = (void *)(t + 1);
kflag = btf_kflag_of(t);
vlen = btf_vlen_of(t);
m = btf_members(t);
vlen = btf_vlen(t);
/* all non-bitfield fields have to be naturally aligned */
for (i = 0; i < vlen; i++, m++) {
align = btf_align_of(btf, m->type);
bit_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
bit_sz = btf_member_bitfield_size(t, i);
if (bit_sz == 0 && m->offset % (8 * align) != 0)
return true;
}
......@@ -807,7 +780,7 @@ static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id,
const struct btf_type *t)
{
btf_dump_printf(d, "%s %s",
btf_kind_of(t) == BTF_KIND_STRUCT ? "struct" : "union",
btf_is_struct(t) ? "struct" : "union",
btf_dump_type_name(d, id));
}
......@@ -816,12 +789,11 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
const struct btf_type *t,
int lvl)
{
const struct btf_member *m = (void *)(t + 1);
bool kflag = btf_kflag_of(t), is_struct;
const struct btf_member *m = btf_members(t);
bool is_struct = btf_is_struct(t);
int align, i, packed, off = 0;
__u16 vlen = btf_vlen_of(t);
__u16 vlen = btf_vlen(t);
is_struct = btf_kind_of(t) == BTF_KIND_STRUCT;
packed = is_struct ? btf_is_struct_packed(d->btf, id, t) : 0;
align = packed ? 1 : btf_align_of(d->btf, id);
......@@ -835,8 +807,8 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
int m_off, m_sz;
fname = btf_name_of(d, m->name_off);
m_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
m_off = kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
m_sz = btf_member_bitfield_size(t, i);
m_off = btf_member_bit_offset(t, i);
align = packed ? 1 : btf_align_of(d->btf, m->type);
btf_dump_emit_bit_padding(d, off, m_off, m_sz, align, lvl + 1);
......@@ -870,8 +842,8 @@ static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id,
const struct btf_type *t,
int lvl)
{
const struct btf_enum *v = (void *)(t+1);
__u16 vlen = btf_vlen_of(t);
const struct btf_enum *v = btf_enum(t);
__u16 vlen = btf_vlen(t);
const char *name;
size_t dup_cnt;
int i;
......@@ -905,7 +877,7 @@ static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id,
{
const char *name = btf_dump_type_name(d, id);
if (btf_kflag_of(t))
if (btf_kflag(t))
btf_dump_printf(d, "union %s", name);
else
btf_dump_printf(d, "struct %s", name);
......@@ -987,7 +959,6 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
struct id_stack decl_stack;
const struct btf_type *t;
int err, stack_start;
__u16 kind;
stack_start = d->decl_stack_cnt;
for (;;) {
......@@ -1008,8 +979,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
break;
t = btf__type_by_id(d->btf, id);
kind = btf_kind_of(t);
switch (kind) {
switch (btf_kind(t)) {
case BTF_KIND_PTR:
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
......@@ -1017,12 +987,9 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
case BTF_KIND_FUNC_PROTO:
id = t->type;
break;
case BTF_KIND_ARRAY: {
const struct btf_array *a = (void *)(t + 1);
id = a->type;
case BTF_KIND_ARRAY:
id = btf_array(t)->type;
break;
}
case BTF_KIND_INT:
case BTF_KIND_ENUM:
case BTF_KIND_FWD:
......@@ -1032,7 +999,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
goto done;
default:
pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n",
kind, id);
btf_kind(t), id);
goto done;
}
}
......@@ -1070,7 +1037,7 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack)
id = decl_stack->ids[decl_stack->cnt - 1];
t = btf__type_by_id(d->btf, id);
switch (btf_kind_of(t)) {
switch (btf_kind(t)) {
case BTF_KIND_VOLATILE:
btf_dump_printf(d, "volatile ");
break;
......@@ -1087,20 +1054,6 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack)
}
}
static bool btf_is_mod_kind(const struct btf *btf, __u32 id)
{
const struct btf_type *t = btf__type_by_id(btf, id);
switch (btf_kind_of(t)) {
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
return true;
default:
return false;
}
}
static void btf_dump_emit_name(const struct btf_dump *d,
const char *name, bool last_was_ptr)
{
......@@ -1139,7 +1092,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
}
t = btf__type_by_id(d->btf, id);
kind = btf_kind_of(t);
kind = btf_kind(t);
switch (kind) {
case BTF_KIND_INT:
......@@ -1185,7 +1138,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
btf_dump_printf(d, " restrict");
break;
case BTF_KIND_ARRAY: {
const struct btf_array *a = (void *)(t + 1);
const struct btf_array *a = btf_array(t);
const struct btf_type *next_t;
__u32 next_id;
bool multidim;
......@@ -1201,7 +1154,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
*/
while (decls->cnt) {
next_id = decls->ids[decls->cnt - 1];
if (btf_is_mod_kind(d->btf, next_id))
next_t = btf__type_by_id(d->btf, next_id);
if (btf_is_mod(next_t))
decls->cnt--;
else
break;
......@@ -1214,7 +1168,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
}
next_t = btf__type_by_id(d->btf, next_id);
multidim = btf_kind_of(next_t) == BTF_KIND_ARRAY;
multidim = btf_is_array(next_t);
/* we need space if we have named non-pointer */
if (fname[0] && !last_was_ptr)
btf_dump_printf(d, " ");
......@@ -1228,8 +1182,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
return;
}
case BTF_KIND_FUNC_PROTO: {
const struct btf_param *p = (void *)(t + 1);
__u16 vlen = btf_vlen_of(t);
const struct btf_param *p = btf_params(t);
__u16 vlen = btf_vlen(t);
int i;
btf_dump_emit_mods(d, decls);
......
tools/lib/bpf/libbpf.c
View file @ 726e333f
......@@ -38,6 +38,7 @@
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/vfs.h>
#include <sys/utsname.h>
#include <tools/libc_compat.h>
#include <libelf.h>
#include <gelf.h>
......@@ -47,6 +48,7 @@
#include "btf.h"
#include "str_error.h"
#include "libbpf_internal.h"
#include "hashmap.h"
#ifndef EM_BPF
#define EM_BPF 247
......@@ -1015,23 +1017,21 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict)
return 0;
}
static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf,
__u32 id)
static const struct btf_type *
skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id)
{
const struct btf_type *t = btf__type_by_id(btf, id);
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;
}
if (res_id)
*res_id = id;
while (btf_is_mod(t) || btf_is_typedef(t)) {
if (res_id)
*res_id = t->type;
t = btf__type_by_id(btf, t->type);
}
return t;
}
/*
......@@ -1044,14 +1044,14 @@ static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf,
static bool get_map_field_int(const char *map_name, const struct btf *btf,
const struct btf_type *def,
const struct btf_member *m, __u32 *res) {
const struct btf_type *t = skip_mods_and_typedefs(btf, m->type);
const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL);
const char *name = btf__name_by_offset(btf, m->name_off);
const struct btf_array *arr_info;
const struct btf_type *arr_t;
if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) {
if (!btf_is_ptr(t)) {
pr_warning("map '%s': attr '%s': expected PTR, got %u.\n",
map_name, name, BTF_INFO_KIND(t->info));
map_name, name, btf_kind(t));
return false;
}
......@@ -1061,12 +1061,12 @@ static bool get_map_field_int(const char *map_name, const struct btf *btf,
map_name, name, t->type);
return false;
}
if (BTF_INFO_KIND(arr_t->info) != BTF_KIND_ARRAY) {
if (!btf_is_array(arr_t)) {
pr_warning("map '%s': attr '%s': expected ARRAY, got %u.\n",
map_name, name, BTF_INFO_KIND(arr_t->info));
map_name, name, btf_kind(arr_t));
return false;
}
arr_info = (const void *)(arr_t + 1);
arr_info = btf_array(arr_t);
*res = arr_info->nelems;
return true;
}
......@@ -1084,11 +1084,11 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
struct bpf_map *map;
int vlen, i;
vi = (const struct btf_var_secinfo *)(const void *)(sec + 1) + var_idx;
vi = btf_var_secinfos(sec) + var_idx;
var = btf__type_by_id(obj->btf, vi->type);
var_extra = (const void *)(var + 1);
var_extra = btf_var(var);
map_name = btf__name_by_offset(obj->btf, var->name_off);
vlen = BTF_INFO_VLEN(var->info);
vlen = btf_vlen(var);
if (map_name == NULL || map_name[0] == '\0') {
pr_warning("map #%d: empty name.\n", var_idx);
......@@ -1098,9 +1098,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
pr_warning("map '%s' BTF data is corrupted.\n", map_name);
return -EINVAL;
}
if (BTF_INFO_KIND(var->info) != BTF_KIND_VAR) {
if (!btf_is_var(var)) {
pr_warning("map '%s': unexpected var kind %u.\n",
map_name, BTF_INFO_KIND(var->info));
map_name, btf_kind(var));
return -EINVAL;
}
if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED &&
......@@ -1110,10 +1110,10 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
return -EOPNOTSUPP;
}
def = skip_mods_and_typedefs(obj->btf, var->type);
if (BTF_INFO_KIND(def->info) != BTF_KIND_STRUCT) {
def = skip_mods_and_typedefs(obj->btf, var->type, NULL);
if (!btf_is_struct(def)) {
pr_warning("map '%s': unexpected def kind %u.\n",
map_name, BTF_INFO_KIND(var->info));
map_name, btf_kind(var));
return -EINVAL;
}
if (def->size > vi->size) {
......@@ -1136,8 +1136,8 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
pr_debug("map '%s': at sec_idx %d, offset %zu.\n",
map_name, map->sec_idx, map->sec_offset);
vlen = BTF_INFO_VLEN(def->info);
m = (const void *)(def + 1);
vlen = btf_vlen(def);
m = btf_members(def);
for (i = 0; i < vlen; i++, m++) {
const char *name = btf__name_by_offset(obj->btf, m->name_off);
......@@ -1187,9 +1187,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
map_name, m->type);
return -EINVAL;
}
if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) {
if (!btf_is_ptr(t)) {
pr_warning("map '%s': key spec is not PTR: %u.\n",
map_name, BTF_INFO_KIND(t->info));
map_name, btf_kind(t));
return -EINVAL;
}
sz = btf__resolve_size(obj->btf, t->type);
......@@ -1230,9 +1230,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj,
map_name, m->type);
return -EINVAL;
}
if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) {
if (!btf_is_ptr(t)) {
pr_warning("map '%s': value spec is not PTR: %u.\n",
map_name, BTF_INFO_KIND(t->info));
map_name, btf_kind(t));
return -EINVAL;
}
sz = btf__resolve_size(obj->btf, t->type);
......@@ -1293,7 +1293,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
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)
if (!btf_is_datasec(t))
continue;
name = btf__name_by_offset(obj->btf, t->name_off);
if (strcmp(name, MAPS_ELF_SEC) == 0) {
......@@ -1307,7 +1307,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict)
return -ENOENT;
}
vlen = BTF_INFO_VLEN(sec->info);
vlen = btf_vlen(sec);
for (i = 0; i < vlen; i++) {
err = bpf_object__init_user_btf_map(obj, sec, i,
obj->efile.btf_maps_shndx,
......@@ -1368,24 +1368,22 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj)
struct btf *btf = obj->btf;
struct btf_type *t;
int i, j, vlen;
__u16 kind;
if (!obj->btf || (has_func && has_datasec))
return;
for (i = 1; i <= btf__get_nr_types(btf); i++) {
t = (struct btf_type *)btf__type_by_id(btf, i);
kind = BTF_INFO_KIND(t->info);
if (!has_datasec && kind == BTF_KIND_VAR) {
if (!has_datasec && btf_is_var(t)) {
/* replace VAR with INT */
t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0);
t->size = sizeof(int);
*(int *)(t+1) = BTF_INT_ENC(0, 0, 32);
} else if (!has_datasec && kind == BTF_KIND_DATASEC) {
*(int *)(t + 1) = BTF_INT_ENC(0, 0, 32);
} else if (!has_datasec && btf_is_datasec(t)) {
/* replace DATASEC with STRUCT */
struct btf_var_secinfo *v = (void *)(t + 1);
struct btf_member *m = (void *)(t + 1);
const struct btf_var_secinfo *v = btf_var_secinfos(t);
struct btf_member *m = btf_members(t);
struct btf_type *vt;
char *name;
......@@ -1396,7 +1394,7 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj)
name++;
}
vlen = BTF_INFO_VLEN(t->info);
vlen = btf_vlen(t);
t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen);
for (j = 0; j < vlen; j++, v++, m++) {
/* order of field assignments is important */
......@@ -1406,12 +1404,12 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj)
vt = (void *)btf__type_by_id(btf, v->type);
m->name_off = vt->name_off;
}
} else if (!has_func && kind == BTF_KIND_FUNC_PROTO) {
} else if (!has_func && btf_is_func_proto(t)) {
/* replace FUNC_PROTO with ENUM */
vlen = BTF_INFO_VLEN(t->info);
vlen = btf_vlen(t);
t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen);
t->size = sizeof(__u32); /* kernel enforced */
} else if (!has_func && kind == BTF_KIND_FUNC) {
} else if (!has_func && btf_is_func(t)) {
/* replace FUNC with TYPEDEF */
t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0);
}
......@@ -2292,6 +2290,844 @@ bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj,
return 0;
}
#define BPF_CORE_SPEC_MAX_LEN 64
/* represents BPF CO-RE field or array element accessor */
struct bpf_core_accessor {
__u32 type_id; /* struct/union type or array element type */
__u32 idx; /* field index or array index */
const char *name; /* field name or NULL for array accessor */
};
struct bpf_core_spec {
const struct btf *btf;
/* high-level spec: named fields and array indices only */
struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN];
/* high-level spec length */
int len;
/* raw, low-level spec: 1-to-1 with accessor spec string */
int raw_spec[BPF_CORE_SPEC_MAX_LEN];
/* raw spec length */
int raw_len;
/* field byte offset represented by spec */
__u32 offset;
};
static bool str_is_empty(const char *s)
{
return !s || !s[0];
}
/*
* Turn bpf_offset_reloc into a low- and high-level spec representation,
* validating correctness along the way, as well as calculating resulting
* field offset (in bytes), specified by accessor string. Low-level spec
* captures every single level of nestedness, including traversing anonymous
* struct/union members. High-level one only captures semantically meaningful
* "turning points": named fields and array indicies.
* E.g., for this case:
*
* struct sample {
* int __unimportant;
* struct {
* int __1;
* int __2;
* int a[7];
* };
* };
*
* struct sample *s = ...;
*
* int x = &s->a[3]; // access string = '0:1:2:3'
*
* Low-level spec has 1:1 mapping with each element of access string (it's
* just a parsed access string representation): [0, 1, 2, 3].
*
* High-level spec will capture only 3 points:
* - intial zero-index access by pointer (&s->... is the same as &s[0]...);
* - field 'a' access (corresponds to '2' in low-level spec);
* - array element #3 access (corresponds to '3' in low-level spec).
*
*/
static int bpf_core_spec_parse(const struct btf *btf,
__u32 type_id,
const char *spec_str,
struct bpf_core_spec *spec)
{
int access_idx, parsed_len, i;
const struct btf_type *t;
const char *name;
__u32 id;
__s64 sz;
if (str_is_empty(spec_str) || *spec_str == ':')
return -EINVAL;
memset(spec, 0, sizeof(*spec));
spec->btf = btf;
/* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */
while (*spec_str) {
if (*spec_str == ':')
++spec_str;
if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1)
return -EINVAL;
if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN)
return -E2BIG;
spec_str += parsed_len;
spec->raw_spec[spec->raw_len++] = access_idx;
}
if (spec->raw_len == 0)
return -EINVAL;
/* first spec value is always reloc type array index */
t = skip_mods_and_typedefs(btf, type_id, &id);
if (!t)
return -EINVAL;
access_idx = spec->raw_spec[0];
spec->spec[0].type_id = id;
spec->spec[0].idx = access_idx;
spec->len++;
sz = btf__resolve_size(btf, id);
if (sz < 0)
return sz;
spec->offset = access_idx * sz;
for (i = 1; i < spec->raw_len; i++) {
t = skip_mods_and_typedefs(btf, id, &id);
if (!t)
return -EINVAL;
access_idx = spec->raw_spec[i];
if (btf_is_composite(t)) {
const struct btf_member *m;
__u32 offset;
if (access_idx >= btf_vlen(t))
return -EINVAL;
if (btf_member_bitfield_size(t, access_idx))
return -EINVAL;
offset = btf_member_bit_offset(t, access_idx);
if (offset % 8)
return -EINVAL;
spec->offset += offset / 8;
m = btf_members(t) + access_idx;
if (m->name_off) {
name = btf__name_by_offset(btf, m->name_off);
if (str_is_empty(name))
return -EINVAL;
spec->spec[spec->len].type_id = id;
spec->spec[spec->len].idx = access_idx;
spec->spec[spec->len].name = name;
spec->len++;
}
id = m->type;
} else if (btf_is_array(t)) {
const struct btf_array *a = btf_array(t);
t = skip_mods_and_typedefs(btf, a->type, &id);
if (!t || access_idx >= a->nelems)
return -EINVAL;
spec->spec[spec->len].type_id = id;
spec->spec[spec->len].idx = access_idx;
spec->len++;
sz = btf__resolve_size(btf, id);
if (sz < 0)
return sz;
spec->offset += access_idx * sz;
} else {
pr_warning("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %d\n",
type_id, spec_str, i, id, btf_kind(t));
return -EINVAL;
}
}
return 0;
}
static bool bpf_core_is_flavor_sep(const char *s)
{
/* check X___Y name pattern, where X and Y are not underscores */
return s[0] != '_' && /* X */
s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */
s[4] != '_'; /* Y */
}
/* Given 'some_struct_name___with_flavor' return the length of a name prefix
* before last triple underscore. Struct name part after last triple
* underscore is ignored by BPF CO-RE relocation during relocation matching.
*/
static size_t bpf_core_essential_name_len(const char *name)
{
size_t n = strlen(name);
int i;
for (i = n - 5; i >= 0; i--) {
if (bpf_core_is_flavor_sep(name + i))
return i + 1;
}
return n;
}
/* dynamically sized list of type IDs */
struct ids_vec {
__u32 *data;
int len;
};
static void bpf_core_free_cands(struct ids_vec *cand_ids)
{
free(cand_ids->data);
free(cand_ids);
}
static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf,
__u32 local_type_id,
const struct btf *targ_btf)
{
size_t local_essent_len, targ_essent_len;
const char *local_name, *targ_name;
const struct btf_type *t;
struct ids_vec *cand_ids;
__u32 *new_ids;
int i, err, n;
t = btf__type_by_id(local_btf, local_type_id);
if (!t)
return ERR_PTR(-EINVAL);
local_name = btf__name_by_offset(local_btf, t->name_off);
if (str_is_empty(local_name))
return ERR_PTR(-EINVAL);
local_essent_len = bpf_core_essential_name_len(local_name);
cand_ids = calloc(1, sizeof(*cand_ids));
if (!cand_ids)
return ERR_PTR(-ENOMEM);
n = btf__get_nr_types(targ_btf);
for (i = 1; i <= n; i++) {
t = btf__type_by_id(targ_btf, i);
targ_name = btf__name_by_offset(targ_btf, t->name_off);
if (str_is_empty(targ_name))
continue;
targ_essent_len = bpf_core_essential_name_len(targ_name);
if (targ_essent_len != local_essent_len)
continue;
if (strncmp(local_name, targ_name, local_essent_len) == 0) {
pr_debug("[%d] %s: found candidate [%d] %s\n",
local_type_id, local_name, i, targ_name);
new_ids = realloc(cand_ids->data, cand_ids->len + 1);
if (!new_ids) {
err = -ENOMEM;
goto err_out;
}
cand_ids->data = new_ids;
cand_ids->data[cand_ids->len++] = i;
}
}
return cand_ids;
err_out:
bpf_core_free_cands(cand_ids);
return ERR_PTR(err);
}
/* Check two types for compatibility, skipping const/volatile/restrict and
* typedefs, to ensure we are relocating offset to the compatible entities:
* - any two STRUCTs/UNIONs are compatible and can be mixed;
* - any two FWDs are compatible;
* - any two PTRs are always compatible;
* - for ENUMs, check sizes, names are ignored;
* - for INT, size and bitness should match, signedness is ignored;
* - for ARRAY, dimensionality is ignored, element types are checked for
* compatibility recursively;
* - everything else shouldn't be ever a target of relocation.
* These rules are not set in stone and probably will be adjusted as we get
* more experience with using BPF CO-RE relocations.
*/
static int bpf_core_fields_are_compat(const struct btf *local_btf,
__u32 local_id,
const struct btf *targ_btf,
__u32 targ_id)
{
const struct btf_type *local_type, *targ_type;
recur:
local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id);
targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id);
if (!local_type || !targ_type)
return -EINVAL;
if (btf_is_composite(local_type) && btf_is_composite(targ_type))
return 1;
if (btf_kind(local_type) != btf_kind(targ_type))
return 0;
switch (btf_kind(local_type)) {
case BTF_KIND_FWD:
case BTF_KIND_PTR:
return 1;
case BTF_KIND_ENUM:
return local_type->size == targ_type->size;
case BTF_KIND_INT:
return btf_int_offset(local_type) == 0 &&
btf_int_offset(targ_type) == 0 &&
local_type->size == targ_type->size &&
btf_int_bits(local_type) == btf_int_bits(targ_type);
case BTF_KIND_ARRAY:
local_id = btf_array(local_type)->type;
targ_id = btf_array(targ_type)->type;
goto recur;
default:
pr_warning("unexpected kind %d relocated, local [%d], target [%d]\n",
btf_kind(local_type), local_id, targ_id);
return 0;
}
}
/*
* Given single high-level named field accessor in local type, find
* corresponding high-level accessor for a target type. Along the way,
* maintain low-level spec for target as well. Also keep updating target
* offset.
*
* Searching is performed through recursive exhaustive enumeration of all
* fields of a struct/union. If there are any anonymous (embedded)
* structs/unions, they are recursively searched as well. If field with
* desired name is found, check compatibility between local and target types,
* before returning result.
*
* 1 is returned, if field is found.
* 0 is returned if no compatible field is found.
* <0 is returned on error.
*/
static int bpf_core_match_member(const struct btf *local_btf,
const struct bpf_core_accessor *local_acc,
const struct btf *targ_btf,
__u32 targ_id,
struct bpf_core_spec *spec,
__u32 *next_targ_id)
{
const struct btf_type *local_type, *targ_type;
const struct btf_member *local_member, *m;
const char *local_name, *targ_name;
__u32 local_id;
int i, n, found;
targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id);
if (!targ_type)
return -EINVAL;
if (!btf_is_composite(targ_type))
return 0;
local_id = local_acc->type_id;
local_type = btf__type_by_id(local_btf, local_id);
local_member = btf_members(local_type) + local_acc->idx;
local_name = btf__name_by_offset(local_btf, local_member->name_off);
n = btf_vlen(targ_type);
m = btf_members(targ_type);
for (i = 0; i < n; i++, m++) {
__u32 offset;
/* bitfield relocations not supported */
if (btf_member_bitfield_size(targ_type, i))
continue;
offset = btf_member_bit_offset(targ_type, i);
if (offset % 8)
continue;
/* too deep struct/union/array nesting */
if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN)
return -E2BIG;
/* speculate this member will be the good one */
spec->offset += offset / 8;
spec->raw_spec[spec->raw_len++] = i;
targ_name = btf__name_by_offset(targ_btf, m->name_off);
if (str_is_empty(targ_name)) {
/* embedded struct/union, we need to go deeper */
found = bpf_core_match_member(local_btf, local_acc,
targ_btf, m->type,
spec, next_targ_id);
if (found) /* either found or error */
return found;
} else if (strcmp(local_name, targ_name) == 0) {
/* matching named field */
struct bpf_core_accessor *targ_acc;
targ_acc = &spec->spec[spec->len++];
targ_acc->type_id = targ_id;
targ_acc->idx = i;
targ_acc->name = targ_name;
*next_targ_id = m->type;
found = bpf_core_fields_are_compat(local_btf,
local_member->type,
targ_btf, m->type);
if (!found)
spec->len--; /* pop accessor */
return found;
}
/* member turned out not to be what we looked for */
spec->offset -= offset / 8;
spec->raw_len--;
}
return 0;
}
/*
* Try to match local spec to a target type and, if successful, produce full
* target spec (high-level, low-level + offset).
*/
static int bpf_core_spec_match(struct bpf_core_spec *local_spec,
const struct btf *targ_btf, __u32 targ_id,
struct bpf_core_spec *targ_spec)
{
const struct btf_type *targ_type;
const struct bpf_core_accessor *local_acc;
struct bpf_core_accessor *targ_acc;
int i, sz, matched;
memset(targ_spec, 0, sizeof(*targ_spec));
targ_spec->btf = targ_btf;
local_acc = &local_spec->spec[0];
targ_acc = &targ_spec->spec[0];
for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) {
targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id,
&targ_id);
if (!targ_type)
return -EINVAL;
if (local_acc->name) {
matched = bpf_core_match_member(local_spec->btf,
local_acc,
targ_btf, targ_id,
targ_spec, &targ_id);
if (matched <= 0)
return matched;
} else {
/* for i=0, targ_id is already treated as array element
* type (because it's the original struct), for others
* we should find array element type first
*/
if (i > 0) {
const struct btf_array *a;
if (!btf_is_array(targ_type))
return 0;
a = btf_array(targ_type);
if (local_acc->idx >= a->nelems)
return 0;
if (!skip_mods_and_typedefs(targ_btf, a->type,
&targ_id))
return -EINVAL;
}
/* too deep struct/union/array nesting */
if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN)
return -E2BIG;
targ_acc->type_id = targ_id;
targ_acc->idx = local_acc->idx;
targ_acc->name = NULL;
targ_spec->len++;
targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx;
targ_spec->raw_len++;
sz = btf__resolve_size(targ_btf, targ_id);
if (sz < 0)
return sz;
targ_spec->offset += local_acc->idx * sz;
}
}
return 1;
}
/*
* Patch relocatable BPF instruction.
* Expected insn->imm value is provided for validation, as well as the new
* relocated value.
*
* Currently three kinds of BPF instructions are supported:
* 1. rX = <imm> (assignment with immediate operand);
* 2. rX += <imm> (arithmetic operations with immediate operand);
* 3. *(rX) = <imm> (indirect memory assignment with immediate operand).
*
* If actual insn->imm value is wrong, bail out.
*/
static int bpf_core_reloc_insn(struct bpf_program *prog, int insn_off,
__u32 orig_off, __u32 new_off)
{
struct bpf_insn *insn;
int insn_idx;
__u8 class;
if (insn_off % sizeof(struct bpf_insn))
return -EINVAL;
insn_idx = insn_off / sizeof(struct bpf_insn);
insn = &prog->insns[insn_idx];
class = BPF_CLASS(insn->code);
if (class == BPF_ALU || class == BPF_ALU64) {
if (BPF_SRC(insn->code) != BPF_K)
return -EINVAL;
if (insn->imm != orig_off)
return -EINVAL;
insn->imm = new_off;
pr_debug("prog '%s': patched insn #%d (ALU/ALU64) imm %d -> %d\n",
bpf_program__title(prog, false),
insn_idx, orig_off, new_off);
} else {
pr_warning("prog '%s': trying to relocate unrecognized insn #%d, code:%x, src:%x, dst:%x, off:%x, imm:%x\n",
bpf_program__title(prog, false),
insn_idx, insn->code, insn->src_reg, insn->dst_reg,
insn->off, insn->imm);
return -EINVAL;
}
return 0;
}
/*
* Probe few well-known locations for vmlinux kernel image and try to load BTF
* data out of it to use for target BTF.
*/
static struct btf *bpf_core_find_kernel_btf(void)
{
const char *locations[] = {
"/lib/modules/%1$s/vmlinux-%1$s",
"/usr/lib/modules/%1$s/kernel/vmlinux",
};
char path[PATH_MAX + 1];
struct utsname buf;
struct btf *btf;
int i;
uname(&buf);
for (i = 0; i < ARRAY_SIZE(locations); i++) {
snprintf(path, PATH_MAX, locations[i], buf.release);
if (access(path, R_OK))
continue;
btf = btf__parse_elf(path, NULL);
pr_debug("kernel BTF load from '%s': %ld\n",
path, PTR_ERR(btf));
if (IS_ERR(btf))
continue;
return btf;
}
pr_warning("failed to find valid kernel BTF\n");
return ERR_PTR(-ESRCH);
}
/* Output spec definition in the format:
* [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>,
* where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b
*/
static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec)
{
const struct btf_type *t;
const char *s;
__u32 type_id;
int i;
type_id = spec->spec[0].type_id;
t = btf__type_by_id(spec->btf, type_id);
s = btf__name_by_offset(spec->btf, t->name_off);
libbpf_print(level, "[%u] %s + ", type_id, s);
for (i = 0; i < spec->raw_len; i++)
libbpf_print(level, "%d%s", spec->raw_spec[i],
i == spec->raw_len - 1 ? " => " : ":");
libbpf_print(level, "%u @ &x", spec->offset);
for (i = 0; i < spec->len; i++) {
if (spec->spec[i].name)
libbpf_print(level, ".%s", spec->spec[i].name);
else
libbpf_print(level, "[%u]", spec->spec[i].idx);
}
}
static size_t bpf_core_hash_fn(const void *key, void *ctx)
{
return (size_t)key;
}
static bool bpf_core_equal_fn(const void *k1, const void *k2, void *ctx)
{
return k1 == k2;
}
static void *u32_as_hash_key(__u32 x)
{
return (void *)(uintptr_t)x;
}
/*
* CO-RE relocate single instruction.
*
* The outline and important points of the algorithm:
* 1. For given local type, find corresponding candidate target types.
* Candidate type is a type with the same "essential" name, ignoring
* everything after last triple underscore (___). E.g., `sample`,
* `sample___flavor_one`, `sample___flavor_another_one`, are all candidates
* for each other. Names with triple underscore are referred to as
* "flavors" and are useful, among other things, to allow to
* specify/support incompatible variations of the same kernel struct, which
* might differ between different kernel versions and/or build
* configurations.
*
* N.B. Struct "flavors" could be generated by bpftool's BTF-to-C
* converter, when deduplicated BTF of a kernel still contains more than
* one different types with the same name. In that case, ___2, ___3, etc
* are appended starting from second name conflict. But start flavors are
* also useful to be defined "locally", in BPF program, to extract same
* data from incompatible changes between different kernel
* versions/configurations. For instance, to handle field renames between
* kernel versions, one can use two flavors of the struct name with the
* same common name and use conditional relocations to extract that field,
* depending on target kernel version.
* 2. For each candidate type, try to match local specification to this
* candidate target type. Matching involves finding corresponding
* high-level spec accessors, meaning that all named fields should match,
* as well as all array accesses should be within the actual bounds. Also,
* types should be compatible (see bpf_core_fields_are_compat for details).
* 3. It is supported and expected that there might be multiple flavors
* matching the spec. As long as all the specs resolve to the same set of
* offsets across all candidates, there is not error. If there is any
* ambiguity, CO-RE relocation will fail. This is necessary to accomodate
* imprefection of BTF deduplication, which can cause slight duplication of
* the same BTF type, if some directly or indirectly referenced (by
* pointer) type gets resolved to different actual types in different
* object files. If such situation occurs, deduplicated BTF will end up
* with two (or more) structurally identical types, which differ only in
* types they refer to through pointer. This should be OK in most cases and
* is not an error.
* 4. Candidate types search is performed by linearly scanning through all
* types in target BTF. It is anticipated that this is overall more
* efficient memory-wise and not significantly worse (if not better)
* CPU-wise compared to prebuilding a map from all local type names to
* a list of candidate type names. It's also sped up by caching resolved
* list of matching candidates per each local "root" type ID, that has at
* least one bpf_offset_reloc associated with it. This list is shared
* between multiple relocations for the same type ID and is updated as some
* of the candidates are pruned due to structural incompatibility.
*/
static int bpf_core_reloc_offset(struct bpf_program *prog,
const struct bpf_offset_reloc *relo,
int relo_idx,
const struct btf *local_btf,
const struct btf *targ_btf,
struct hashmap *cand_cache)
{
const char *prog_name = bpf_program__title(prog, false);
struct bpf_core_spec local_spec, cand_spec, targ_spec;
const void *type_key = u32_as_hash_key(relo->type_id);
const struct btf_type *local_type, *cand_type;
const char *local_name, *cand_name;
struct ids_vec *cand_ids;
__u32 local_id, cand_id;
const char *spec_str;
int i, j, err;
local_id = relo->type_id;
local_type = btf__type_by_id(local_btf, local_id);
if (!local_type)
return -EINVAL;
local_name = btf__name_by_offset(local_btf, local_type->name_off);
if (str_is_empty(local_name))
return -EINVAL;
spec_str = btf__name_by_offset(local_btf, relo->access_str_off);
if (str_is_empty(spec_str))
return -EINVAL;
err = bpf_core_spec_parse(local_btf, local_id, spec_str, &local_spec);
if (err) {
pr_warning("prog '%s': relo #%d: parsing [%d] %s + %s failed: %d\n",
prog_name, relo_idx, local_id, local_name, spec_str,
err);
return -EINVAL;
}
pr_debug("prog '%s': relo #%d: spec is ", prog_name, relo_idx);
bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec);
libbpf_print(LIBBPF_DEBUG, "\n");
if (!hashmap__find(cand_cache, type_key, (void **)&cand_ids)) {
cand_ids = bpf_core_find_cands(local_btf, local_id, targ_btf);
if (IS_ERR(cand_ids)) {
pr_warning("prog '%s': relo #%d: target candidate search failed for [%d] %s: %ld",
prog_name, relo_idx, local_id, local_name,
PTR_ERR(cand_ids));
return PTR_ERR(cand_ids);
}
err = hashmap__set(cand_cache, type_key, cand_ids, NULL, NULL);
if (err) {
bpf_core_free_cands(cand_ids);
return err;
}
}
for (i = 0, j = 0; i < cand_ids->len; i++) {
cand_id = cand_ids->data[i];
cand_type = btf__type_by_id(targ_btf, cand_id);
cand_name = btf__name_by_offset(targ_btf, cand_type->name_off);
err = bpf_core_spec_match(&local_spec, targ_btf,
cand_id, &cand_spec);
pr_debug("prog '%s': relo #%d: matching candidate #%d %s against spec ",
prog_name, relo_idx, i, cand_name);
bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec);
libbpf_print(LIBBPF_DEBUG, ": %d\n", err);
if (err < 0) {
pr_warning("prog '%s': relo #%d: matching error: %d\n",
prog_name, relo_idx, err);
return err;
}
if (err == 0)
continue;
if (j == 0) {
targ_spec = cand_spec;
} else if (cand_spec.offset != targ_spec.offset) {
/* if there are many candidates, they should all
* resolve to the same offset
*/
pr_warning("prog '%s': relo #%d: offset ambiguity: %u != %u\n",
prog_name, relo_idx, cand_spec.offset,
targ_spec.offset);
return -EINVAL;
}
cand_ids->data[j++] = cand_spec.spec[0].type_id;
}
cand_ids->len = j;
if (cand_ids->len == 0) {
pr_warning("prog '%s': relo #%d: no matching targets found for [%d] %s + %s\n",
prog_name, relo_idx, local_id, local_name, spec_str);
return -ESRCH;
}
err = bpf_core_reloc_insn(prog, relo->insn_off,
local_spec.offset, targ_spec.offset);
if (err) {
pr_warning("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n",
prog_name, relo_idx, relo->insn_off, err);
return -EINVAL;
}
return 0;
}
static int
bpf_core_reloc_offsets(struct bpf_object *obj, const char *targ_btf_path)
{
const struct btf_ext_info_sec *sec;
const struct bpf_offset_reloc *rec;
const struct btf_ext_info *seg;
struct hashmap_entry *entry;
struct hashmap *cand_cache = NULL;
struct bpf_program *prog;
struct btf *targ_btf;
const char *sec_name;
int i, err = 0;
if (targ_btf_path)
targ_btf = btf__parse_elf(targ_btf_path, NULL);
else
targ_btf = bpf_core_find_kernel_btf();
if (IS_ERR(targ_btf)) {
pr_warning("failed to get target BTF: %ld\n",
PTR_ERR(targ_btf));
return PTR_ERR(targ_btf);
}
cand_cache = hashmap__new(bpf_core_hash_fn, bpf_core_equal_fn, NULL);
if (IS_ERR(cand_cache)) {
err = PTR_ERR(cand_cache);
goto out;
}
seg = &obj->btf_ext->offset_reloc_info;
for_each_btf_ext_sec(seg, sec) {
sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off);
if (str_is_empty(sec_name)) {
err = -EINVAL;
goto out;
}
prog = bpf_object__find_program_by_title(obj, sec_name);
if (!prog) {
pr_warning("failed to find program '%s' for CO-RE offset relocation\n",
sec_name);
err = -EINVAL;
goto out;
}
pr_debug("prog '%s': performing %d CO-RE offset relocs\n",
sec_name, sec->num_info);
for_each_btf_ext_rec(seg, sec, i, rec) {
err = bpf_core_reloc_offset(prog, rec, i, obj->btf,
targ_btf, cand_cache);
if (err) {
pr_warning("prog '%s': relo #%d: failed to relocate: %d\n",
sec_name, i, err);
goto out;
}
}
}
out:
btf__free(targ_btf);
if (!IS_ERR_OR_NULL(cand_cache)) {
hashmap__for_each_entry(cand_cache, entry, i) {
bpf_core_free_cands(entry->value);
}
hashmap__free(cand_cache);
}
return err;
}
static int
bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path)
{
int err = 0;
if (obj->btf_ext->offset_reloc_info.len)
err = bpf_core_reloc_offsets(obj, targ_btf_path);
return err;
}
static int
bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj,
struct reloc_desc *relo)
......@@ -2399,14 +3235,21 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
return 0;
}
static int
bpf_object__relocate(struct bpf_object *obj)
bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path)
{
struct bpf_program *prog;
size_t i;
int err;
if (obj->btf_ext) {
err = bpf_object__relocate_core(obj, targ_btf_path);
if (err) {
pr_warning("failed to perform CO-RE relocations: %d\n",
err);
return err;
}
}
for (i = 0; i < obj->nr_programs; i++) {
prog = &obj->programs[i];
......@@ -2807,7 +3650,7 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr)
obj->loaded = true;
CHECK_ERR(bpf_object__create_maps(obj), err, out);
CHECK_ERR(bpf_object__relocate(obj), err, out);
CHECK_ERR(bpf_object__relocate(obj, attr->target_btf_path), err, out);
CHECK_ERR(bpf_object__load_progs(obj, attr->log_level), err, out);
return 0;
......
tools/lib/bpf/libbpf.h
View file @ 726e333f
......@@ -92,6 +92,7 @@ LIBBPF_API void bpf_object__close(struct bpf_object *object);
struct bpf_object_load_attr {
struct bpf_object *obj;
int log_level;
const char *target_btf_path;
};
/* Load/unload object into/from kernel */
......
tools/lib/bpf/libbpf_internal.h
View file @ 726e333f
......@@ -29,6 +29,10 @@
#ifndef max
# define max(x, y) ((x) < (y) ? (y) : (x))
#endif
#ifndef offsetofend
# define offsetofend(TYPE, FIELD) \
(offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD))
#endif
extern void libbpf_print(enum libbpf_print_level level,
const char *format, ...)
......@@ -46,4 +50,105 @@ do { \
int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
const char *str_sec, size_t str_len);
struct btf_ext_info {
/*
* info points to the individual info section (e.g. func_info and
* line_info) from the .BTF.ext. It does not include the __u32 rec_size.
*/
void *info;
__u32 rec_size;
__u32 len;
};
#define for_each_btf_ext_sec(seg, sec) \
for (sec = (seg)->info; \
(void *)sec < (seg)->info + (seg)->len; \
sec = (void *)sec + sizeof(struct btf_ext_info_sec) + \
(seg)->rec_size * sec->num_info)
#define for_each_btf_ext_rec(seg, sec, i, rec) \
for (i = 0, rec = (void *)&(sec)->data; \
i < (sec)->num_info; \
i++, rec = (void *)rec + (seg)->rec_size)
struct btf_ext {
union {
struct btf_ext_header *hdr;
void *data;
};
struct btf_ext_info func_info;
struct btf_ext_info line_info;
struct btf_ext_info offset_reloc_info;
__u32 data_size;
};
struct btf_ext_info_sec {
__u32 sec_name_off;
__u32 num_info;
/* Followed by num_info * record_size number of bytes */
__u8 data[0];
};
/* The minimum bpf_func_info checked by the loader */
struct bpf_func_info_min {
__u32 insn_off;
__u32 type_id;
};
/* The minimum bpf_line_info checked by the loader */
struct bpf_line_info_min {
__u32 insn_off;
__u32 file_name_off;
__u32 line_off;
__u32 line_col;
};
/* The minimum bpf_offset_reloc checked by the loader
*
* Offset relocation captures the following data:
* - insn_off - instruction offset (in bytes) within a BPF program that needs
* its insn->imm field to be relocated with actual offset;
* - type_id - BTF type ID of the "root" (containing) entity of a relocatable
* offset;
* - access_str_off - offset into corresponding .BTF string section. String
* itself encodes an accessed field using a sequence of field and array
* indicies, separated by colon (:). It's conceptually very close to LLVM's
* getelementptr ([0]) instruction's arguments for identifying offset to
* a field.
*
* Example to provide a better feel.
*
* struct sample {
* int a;
* struct {
* int b[10];
* };
* };
*
* struct sample *s = ...;
* int x = &s->a; // encoded as "0:0" (a is field #0)
* int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
* // b is field #0 inside anon struct, accessing elem #5)
* int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
*
* type_id for all relocs in this example will capture BTF type id of
* `struct sample`.
*
* Such relocation is emitted when using __builtin_preserve_access_index()
* Clang built-in, passing expression that captures field address, e.g.:
*
* bpf_probe_read(&dst, sizeof(dst),
* __builtin_preserve_access_index(&src->a.b.c));
*
* In this case Clang will emit offset relocation recording necessary data to
* be able to find offset of embedded `a.b.c` field within `src` struct.
*
* [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
*/
struct bpf_offset_reloc {
__u32 insn_off;
__u32 type_id;
__u32 access_str_off;
};
#endif /* __LIBBPF_LIBBPF_INTERNAL_H */
tools/testing/selftests/bpf/bpf_helpers.h
View file @ 726e333f
......@@ -504,4 +504,24 @@ struct pt_regs;
(void *)(PT_REGS_FP(ctx) + sizeof(ip))); })
#endif
/*
* BPF_CORE_READ abstracts away bpf_probe_read() call and captures offset
* relocation for source address using __builtin_preserve_access_index()
* built-in, provided by Clang.
*
* __builtin_preserve_access_index() takes as an argument an expression of
* taking an address of a field within struct/union. It makes compiler emit
* a relocation, which records BTF type ID describing root struct/union and an
* accessor string which describes exact embedded field that was used to take
* an address. See detailed description of this relocation format and
* semantics in comments to struct bpf_offset_reloc in libbpf_internal.h.
*
* This relocation allows libbpf to adjust BPF instruction to use correct
* actual field offset, based on target kernel BTF type that matches original
* (local) BTF, used to record relocation.
*/
#define BPF_CORE_READ(dst, src) \
bpf_probe_read((dst), sizeof(*(src)), \
__builtin_preserve_access_index(src))
#endif
tools/testing/selftests/bpf/prog_tests/core_reloc.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "progs/core_reloc_types.h"
#define STRUCT_TO_CHAR_PTR(struct_name) (const char *)&(struct struct_name)
#define FLAVORS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \
.a = 42, \
.b = 0xc001, \
.c = 0xbeef, \
}
#define FLAVORS_CASE_COMMON(name) \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_flavors.o", \
.btf_src_file = "btf__core_reloc_" #name ".o" \
#define FLAVORS_CASE(name) { \
FLAVORS_CASE_COMMON(name), \
.input = FLAVORS_DATA(core_reloc_##name), \
.input_len = sizeof(struct core_reloc_##name), \
.output = FLAVORS_DATA(core_reloc_flavors), \
.output_len = sizeof(struct core_reloc_flavors), \
}
#define FLAVORS_ERR_CASE(name) { \
FLAVORS_CASE_COMMON(name), \
.fails = true, \
}
#define NESTING_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \
.a = { .a = { .a = 42 } }, \
.b = { .b = { .b = 0xc001 } }, \
}
#define NESTING_CASE_COMMON(name) \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_nesting.o", \
.btf_src_file = "btf__core_reloc_" #name ".o"
#define NESTING_CASE(name) { \
NESTING_CASE_COMMON(name), \
.input = NESTING_DATA(core_reloc_##name), \
.input_len = sizeof(struct core_reloc_##name), \
.output = NESTING_DATA(core_reloc_nesting), \
.output_len = sizeof(struct core_reloc_nesting) \
}
#define NESTING_ERR_CASE(name) { \
NESTING_CASE_COMMON(name), \
.fails = true, \
}
#define ARRAYS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \
.a = { [2] = 1 }, \
.b = { [1] = { [2] = { [3] = 2 } } }, \
.c = { [1] = { .c = 3 } }, \
.d = { [0] = { [0] = { .d = 4 } } }, \
}
#define ARRAYS_CASE_COMMON(name) \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_arrays.o", \
.btf_src_file = "btf__core_reloc_" #name ".o"
#define ARRAYS_CASE(name) { \
ARRAYS_CASE_COMMON(name), \
.input = ARRAYS_DATA(core_reloc_##name), \
.input_len = sizeof(struct core_reloc_##name), \
.output = STRUCT_TO_CHAR_PTR(core_reloc_arrays_output) { \
.a2 = 1, \
.b123 = 2, \
.c1c = 3, \
.d00d = 4, \
}, \
.output_len = sizeof(struct core_reloc_arrays_output) \
}
#define ARRAYS_ERR_CASE(name) { \
ARRAYS_CASE_COMMON(name), \
.fails = true, \
}
#define PRIMITIVES_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \
.a = 1, \
.b = 2, \
.c = 3, \
.d = (void *)4, \
.f = (void *)5, \
}
#define PRIMITIVES_CASE_COMMON(name) \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_primitives.o", \
.btf_src_file = "btf__core_reloc_" #name ".o"
#define PRIMITIVES_CASE(name) { \
PRIMITIVES_CASE_COMMON(name), \
.input = PRIMITIVES_DATA(core_reloc_##name), \
.input_len = sizeof(struct core_reloc_##name), \
.output = PRIMITIVES_DATA(core_reloc_primitives), \
.output_len = sizeof(struct core_reloc_primitives), \
}
#define PRIMITIVES_ERR_CASE(name) { \
PRIMITIVES_CASE_COMMON(name), \
.fails = true, \
}
#define MODS_CASE(name) { \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_mods.o", \
.btf_src_file = "btf__core_reloc_" #name ".o", \
.input = STRUCT_TO_CHAR_PTR(core_reloc_##name) { \
.a = 1, \
.b = 2, \
.c = (void *)3, \
.d = (void *)4, \
.e = { [2] = 5 }, \
.f = { [1] = 6 }, \
.g = { .x = 7 }, \
.h = { .y = 8 }, \
}, \
.input_len = sizeof(struct core_reloc_##name), \
.output = STRUCT_TO_CHAR_PTR(core_reloc_mods_output) { \
.a = 1, .b = 2, .c = 3, .d = 4, \
.e = 5, .f = 6, .g = 7, .h = 8, \
}, \
.output_len = sizeof(struct core_reloc_mods_output), \
}
#define PTR_AS_ARR_CASE(name) { \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_ptr_as_arr.o", \
.btf_src_file = "btf__core_reloc_" #name ".o", \
.input = (const char *)&(struct core_reloc_##name []){ \
{ .a = 1 }, \
{ .a = 2 }, \
{ .a = 3 }, \
}, \
.input_len = 3 * sizeof(struct core_reloc_##name), \
.output = STRUCT_TO_CHAR_PTR(core_reloc_ptr_as_arr) { \
.a = 3, \
}, \
.output_len = sizeof(struct core_reloc_ptr_as_arr), \
}
#define INTS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \
.u8_field = 1, \
.s8_field = 2, \
.u16_field = 3, \
.s16_field = 4, \
.u32_field = 5, \
.s32_field = 6, \
.u64_field = 7, \
.s64_field = 8, \
}
#define INTS_CASE_COMMON(name) \
.case_name = #name, \
.bpf_obj_file = "test_core_reloc_ints.o", \
.btf_src_file = "btf__core_reloc_" #name ".o"
#define INTS_CASE(name) { \
INTS_CASE_COMMON(name), \
.input = INTS_DATA(core_reloc_##name), \
.input_len = sizeof(struct core_reloc_##name), \
.output = INTS_DATA(core_reloc_ints), \
.output_len = sizeof(struct core_reloc_ints), \
}
#define INTS_ERR_CASE(name) { \
INTS_CASE_COMMON(name), \
.fails = true, \
}
struct core_reloc_test_case {
const char *case_name;
const char *bpf_obj_file;
const char *btf_src_file;
const char *input;
int input_len;
const char *output;
int output_len;
bool fails;
};
static struct core_reloc_test_case test_cases[] = {
/* validate we can find kernel image and use its BTF for relocs */
{
.case_name = "kernel",
.bpf_obj_file = "test_core_reloc_kernel.o",
.btf_src_file = NULL, /* load from /lib/modules/$(uname -r) */
.input = "",
.input_len = 0,
.output = "\1", /* true */
.output_len = 1,
},
/* validate BPF program can use multiple flavors to match against
* single target BTF type
*/
FLAVORS_CASE(flavors),
FLAVORS_ERR_CASE(flavors__err_wrong_name),
/* various struct/enum nesting and resolution scenarios */
NESTING_CASE(nesting),
NESTING_CASE(nesting___anon_embed),
NESTING_CASE(nesting___struct_union_mixup),
NESTING_CASE(nesting___extra_nesting),
NESTING_CASE(nesting___dup_compat_types),
NESTING_ERR_CASE(nesting___err_missing_field),
NESTING_ERR_CASE(nesting___err_array_field),
NESTING_ERR_CASE(nesting___err_missing_container),
NESTING_ERR_CASE(nesting___err_nonstruct_container),
NESTING_ERR_CASE(nesting___err_array_container),
NESTING_ERR_CASE(nesting___err_dup_incompat_types),
NESTING_ERR_CASE(nesting___err_partial_match_dups),
NESTING_ERR_CASE(nesting___err_too_deep),
/* various array access relocation scenarios */
ARRAYS_CASE(arrays),
ARRAYS_CASE(arrays___diff_arr_dim),
ARRAYS_CASE(arrays___diff_arr_val_sz),
ARRAYS_ERR_CASE(arrays___err_too_small),
ARRAYS_ERR_CASE(arrays___err_too_shallow),
ARRAYS_ERR_CASE(arrays___err_non_array),
ARRAYS_ERR_CASE(arrays___err_wrong_val_type1),
ARRAYS_ERR_CASE(arrays___err_wrong_val_type2),
/* enum/ptr/int handling scenarios */
PRIMITIVES_CASE(primitives),
PRIMITIVES_CASE(primitives___diff_enum_def),
PRIMITIVES_CASE(primitives___diff_func_proto),
PRIMITIVES_CASE(primitives___diff_ptr_type),
PRIMITIVES_ERR_CASE(primitives___err_non_enum),
PRIMITIVES_ERR_CASE(primitives___err_non_int),
PRIMITIVES_ERR_CASE(primitives___err_non_ptr),
/* const/volatile/restrict and typedefs scenarios */
MODS_CASE(mods),
MODS_CASE(mods___mod_swap),
MODS_CASE(mods___typedefs),
/* handling "ptr is an array" semantics */
PTR_AS_ARR_CASE(ptr_as_arr),
PTR_AS_ARR_CASE(ptr_as_arr___diff_sz),
/* int signedness/sizing/bitfield handling */
INTS_CASE(ints),
INTS_CASE(ints___bool),
INTS_CASE(ints___reverse_sign),
INTS_ERR_CASE(ints___err_bitfield),
INTS_ERR_CASE(ints___err_wrong_sz_8),
INTS_ERR_CASE(ints___err_wrong_sz_16),
INTS_ERR_CASE(ints___err_wrong_sz_32),
INTS_ERR_CASE(ints___err_wrong_sz_64),
/* validate edge cases of capturing relocations */
{
.case_name = "misc",
.bpf_obj_file = "test_core_reloc_misc.o",
.btf_src_file = "btf__core_reloc_misc.o",
.input = (const char *)&(struct core_reloc_misc_extensible[]){
{ .a = 1 },
{ .a = 2 }, /* not read */
{ .a = 3 },
},
.input_len = 4 * sizeof(int),
.output = STRUCT_TO_CHAR_PTR(core_reloc_misc_output) {
.a = 1,
.b = 1,
.c = 0, /* BUG in clang, should be 3 */
},
.output_len = sizeof(struct core_reloc_misc_output),
},
};
struct data {
char in[256];
char out[256];
};
void test_core_reloc(void)
{
const char *probe_name = "raw_tracepoint/sys_enter";
struct bpf_object_load_attr load_attr = {};
struct core_reloc_test_case *test_case;
int err, duration = 0, i, equal;
struct bpf_link *link = NULL;
struct bpf_map *data_map;
struct bpf_program *prog;
struct bpf_object *obj;
const int zero = 0;
struct data data;
for (i = 0; i < ARRAY_SIZE(test_cases); i++) {
test_case = &test_cases[i];
if (!test__start_subtest(test_case->case_name))
continue;
obj = bpf_object__open(test_case->bpf_obj_file);
if (CHECK(IS_ERR_OR_NULL(obj), "obj_open",
"failed to open '%s': %ld\n",
test_case->bpf_obj_file, PTR_ERR(obj)))
continue;
prog = bpf_object__find_program_by_title(obj, probe_name);
if (CHECK(!prog, "find_probe",
"prog '%s' not found\n", probe_name))
goto cleanup;
bpf_program__set_type(prog, BPF_PROG_TYPE_RAW_TRACEPOINT);
load_attr.obj = obj;
load_attr.log_level = 0;
load_attr.target_btf_path = test_case->btf_src_file;
err = bpf_object__load_xattr(&load_attr);
if (test_case->fails) {
CHECK(!err, "obj_load_fail",
"should fail to load prog '%s'\n", probe_name);
goto cleanup;
} else {
if (CHECK(err, "obj_load",
"failed to load prog '%s': %d\n",
probe_name, err))
goto cleanup;
}
link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n",
PTR_ERR(link)))
goto cleanup;
data_map = bpf_object__find_map_by_name(obj, "test_cor.bss");
if (CHECK(!data_map, "find_data_map", "data map not found\n"))
goto cleanup;
memset(&data, 0, sizeof(data));
memcpy(data.in, test_case->input, test_case->input_len);
err = bpf_map_update_elem(bpf_map__fd(data_map),
&zero, &data, 0);
if (CHECK(err, "update_data_map",
"failed to update .data map: %d\n", err))
goto cleanup;
/* trigger test run */
usleep(1);
err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &data);
if (CHECK(err, "get_result",
"failed to get output data: %d\n", err))
goto cleanup;
equal = memcmp(data.out, test_case->output,
test_case->output_len) == 0;
if (CHECK(!equal, "check_result",
"input/output data don't match\n")) {
int j;
for (j = 0; j < test_case->input_len; j++) {
printf("input byte #%d: 0x%02hhx\n",
j, test_case->input[j]);
}
for (j = 0; j < test_case->output_len; j++) {
printf("output byte #%d: EXP 0x%02hhx GOT 0x%02hhx\n",
j, test_case->output[j], data.out[j]);
}
goto cleanup;
}
cleanup:
if (!IS_ERR_OR_NULL(link)) {
bpf_link__destroy(link);
link = NULL;
}
bpf_object__close(obj);
}
}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_dim.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___diff_arr_dim x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_val_sz.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___diff_arr_val_sz x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_non_array.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___err_non_array x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_shallow.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___err_too_shallow x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_small.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___err_too_small x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type1.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___err_wrong_val_type1 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type2.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_arrays___err_wrong_val_type2 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_flavors.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_flavors x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_flavors__err_wrong_name.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_flavors__err_wrong_name x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___bool.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___bool x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_bitfield.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___err_bitfield x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_16.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___err_wrong_sz_16 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_32.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___err_wrong_sz_32 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_64.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___err_wrong_sz_64 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_8.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___err_wrong_sz_8 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ints___reverse_sign.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ints___reverse_sign x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_misc.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f1(struct core_reloc_misc___a x) {}
void f2(struct core_reloc_misc___b x) {}
void f3(struct core_reloc_misc_extensible x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_mods.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_mods x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_mods___mod_swap.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_mods___mod_swap x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_mods___typedefs.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_mods___typedefs x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___anon_embed.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___anon_embed x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___dup_compat_types.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f1(struct core_reloc_nesting___dup_compat_types x) {}
void f2(struct core_reloc_nesting___dup_compat_types__2 x) {}
void f3(struct core_reloc_nesting___dup_compat_types__3 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_container.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_array_container x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_field.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_array_field x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_dup_incompat_types.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f1(struct core_reloc_nesting___err_dup_incompat_types__1 x) {}
void f2(struct core_reloc_nesting___err_dup_incompat_types__2 x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_container.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_missing_container x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_field.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_missing_field x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_nonstruct_container.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_nonstruct_container x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_partial_match_dups.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f1(struct core_reloc_nesting___err_partial_match_dups__a x) {}
void f2(struct core_reloc_nesting___err_partial_match_dups__b x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_too_deep.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___err_too_deep x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___extra_nesting.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___extra_nesting x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___struct_union_mixup.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_nesting___struct_union_mixup x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_enum_def.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___diff_enum_def x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_func_proto.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___diff_func_proto x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_ptr_type.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___diff_ptr_type x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_enum.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___err_non_enum x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_int.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___err_non_int x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_ptr.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_primitives___err_non_ptr x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ptr_as_arr x) {}
tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr___diff_sz.c 0 → 100644
View file @ 726e333f
#include "core_reloc_types.h"
void f(struct core_reloc_ptr_as_arr___diff_sz x) {}
tools/testing/selftests/bpf/progs/core_reloc_types.h 0 → 100644
View file @ 726e333f
#include <stdint.h>
#include <stdbool.h>
/*
* FLAVORS
*/
struct core_reloc_flavors {
int a;
int b;
int c;
};
/* this is not a flavor, as it doesn't have triple underscore */
struct core_reloc_flavors__err_wrong_name {
int a;
int b;
int c;
};
/*
* NESTING
*/
/* original set up, used to record relocations in BPF program */
struct core_reloc_nesting_substruct {
int a;
};
union core_reloc_nesting_subunion {
int b;
};
struct core_reloc_nesting {
union {
struct core_reloc_nesting_substruct a;
} a;
struct {
union core_reloc_nesting_subunion b;
} b;
};
/* inlined anonymous struct/union instead of named structs in original */
struct core_reloc_nesting___anon_embed {
int __just_for_padding;
union {
struct {
int a;
} a;
} a;
struct {
union {
int b;
} b;
} b;
};
/* different mix of nested structs/unions than in original */
struct core_reloc_nesting___struct_union_mixup {
int __a;
struct {
int __a;
union {
char __a;
int a;
} a;
} a;
int __b;
union {
int __b;
union {
char __b;
int b;
} b;
} b;
};
/* extra anon structs/unions, but still valid a.a.a and b.b.b accessors */
struct core_reloc_nesting___extra_nesting {
int __padding;
struct {
struct {
struct {
struct {
union {
int a;
} a;
};
};
} a;
int __some_more;
struct {
union {
union {
union {
struct {
int b;
};
} b;
};
} b;
};
};
};
/* three flavors of same struct with different structure but same layout for
* a.a.a and b.b.b, thus successfully resolved and relocatable */
struct core_reloc_nesting___dup_compat_types {
char __just_for_padding;
/* 3 more bytes of padding */
struct {
struct {
int a; /* offset 4 */
} a;
} a;
long long __more_padding;
struct {
struct {
int b; /* offset 16 */
} b;
} b;
};
struct core_reloc_nesting___dup_compat_types__2 {
int __aligned_padding;
struct {
int __trickier_noop[0];
struct {
char __some_more_noops[0];
int a; /* offset 4 */
} a;
} a;
int __more_padding;
struct {
struct {
struct {
int __critical_padding;
int b; /* offset 16 */
} b;
int __does_not_matter;
};
} b;
int __more_irrelevant_stuff;
};
struct core_reloc_nesting___dup_compat_types__3 {
char __correct_padding[4];
struct {
struct {
int a; /* offset 4 */
} a;
} a;
/* 8 byte padding due to next struct's alignment */
struct {
struct {
int b;
} b;
} b __attribute__((aligned(16)));
};
/* b.b.b field is missing */
struct core_reloc_nesting___err_missing_field {
struct {
struct {
int a;
} a;
} a;
struct {
struct {
int x;
} b;
} b;
};
/* b.b.b field is an array of integers instead of plain int */
struct core_reloc_nesting___err_array_field {
struct {
struct {
int a;
} a;
} a;
struct {
struct {
int b[1];
} b;
} b;
};
/* middle b container is missing */
struct core_reloc_nesting___err_missing_container {
struct {
struct {
int a;
} a;
} a;
struct {
int x;
} b;
};
/* middle b container is referenced through pointer instead of being embedded */
struct core_reloc_nesting___err_nonstruct_container {
struct {
struct {
int a;
} a;
} a;
struct {
struct {
int b;
} *b;
} b;
};
/* middle b container is an array of structs instead of plain struct */
struct core_reloc_nesting___err_array_container {
struct {
struct {
int a;
} a;
} a;
struct {
struct {
int b;
} b[1];
} b;
};
/* two flavors of same struct with incompatible layout for b.b.b */
struct core_reloc_nesting___err_dup_incompat_types__1 {
struct {
struct {
int a; /* offset 0 */
} a;
} a;
struct {
struct {
int b; /* offset 4 */
} b;
} b;
};
struct core_reloc_nesting___err_dup_incompat_types__2 {
struct {
struct {
int a; /* offset 0 */
} a;
} a;
int __extra_padding;
struct {
struct {
int b; /* offset 8 (!) */
} b;
} b;
};
/* two flavors of same struct having one of a.a.a and b.b.b, but not both */
struct core_reloc_nesting___err_partial_match_dups__a {
struct {
struct {
int a;
} a;
} a;
};
struct core_reloc_nesting___err_partial_match_dups__b {
struct {
struct {
int b;
} b;
} b;
};
struct core_reloc_nesting___err_too_deep {
struct {
struct {
int a;
} a;
} a;
/* 65 levels of nestedness for b.b.b */
struct {
struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
struct { struct { struct { struct { struct {
/* this one is one too much */
struct {
int b;
};
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
}; }; }; }; };
} b;
} b;
};
/*
* ARRAYS
*/
struct core_reloc_arrays_output {
int a2;
char b123;
int c1c;
int d00d;
};
struct core_reloc_arrays_substruct {
int c;
int d;
};
struct core_reloc_arrays {
int a[5];
char b[2][3][4];
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
/* bigger array dimensions */
struct core_reloc_arrays___diff_arr_dim {
int a[7];
char b[3][4][5];
struct core_reloc_arrays_substruct c[4];
struct core_reloc_arrays_substruct d[2][3];
};
/* different size of array's value (struct) */
struct core_reloc_arrays___diff_arr_val_sz {
int a[5];
char b[2][3][4];
struct {
int __padding1;
int c;
int __padding2;
} c[3];
struct {
int __padding1;
int d;
int __padding2;
} d[1][2];
};
struct core_reloc_arrays___err_too_small {
int a[2]; /* this one is too small */
char b[2][3][4];
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
struct core_reloc_arrays___err_too_shallow {
int a[5];
char b[2][3]; /* this one lacks one dimension */
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
struct core_reloc_arrays___err_non_array {
int a; /* not an array */
char b[2][3][4];
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
struct core_reloc_arrays___err_wrong_val_type1 {
char a[5]; /* char instead of int */
char b[2][3][4];
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
struct core_reloc_arrays___err_wrong_val_type2 {
int a[5];
char b[2][3][4];
int c[3]; /* value is not a struct */
struct core_reloc_arrays_substruct d[1][2];
};
/*
* PRIMITIVES
*/
enum core_reloc_primitives_enum {
A = 0,
B = 1,
};
struct core_reloc_primitives {
char a;
int b;
enum core_reloc_primitives_enum c;
void *d;
int (*f)(const char *);
};
struct core_reloc_primitives___diff_enum_def {
char a;
int b;
void *d;
int (*f)(const char *);
enum {
X = 100,
Y = 200,
} c; /* inline enum def with differing set of values */
};
struct core_reloc_primitives___diff_func_proto {
void (*f)(int); /* incompatible function prototype */
void *d;
enum core_reloc_primitives_enum c;
int b;
char a;
};
struct core_reloc_primitives___diff_ptr_type {
const char * const d; /* different pointee type + modifiers */
char a;
int b;
enum core_reloc_primitives_enum c;
int (*f)(const char *);
};
struct core_reloc_primitives___err_non_enum {
char a[1];
int b;
int c; /* int instead of enum */
void *d;
int (*f)(const char *);
};
struct core_reloc_primitives___err_non_int {
char a[1];
int *b; /* ptr instead of int */
enum core_reloc_primitives_enum c;
void *d;
int (*f)(const char *);
};
struct core_reloc_primitives___err_non_ptr {
char a[1];
int b;
enum core_reloc_primitives_enum c;
int d; /* int instead of ptr */
int (*f)(const char *);
};
/*
* MODS
*/
struct core_reloc_mods_output {
int a, b, c, d, e, f, g, h;
};
typedef const int int_t;
typedef const char *char_ptr_t;
typedef const int arr_t[7];
struct core_reloc_mods_substruct {
int x;
int y;
};
typedef struct {
int x;
int y;
} core_reloc_mods_substruct_t;
struct core_reloc_mods {
int a;
int_t b;
char *c;
char_ptr_t d;
int e[3];
arr_t f;
struct core_reloc_mods_substruct g;
core_reloc_mods_substruct_t h;
};
/* a/b, c/d, e/f, and g/h pairs are swapped */
struct core_reloc_mods___mod_swap {
int b;
int_t a;
char *d;
char_ptr_t c;
int f[3];
arr_t e;
struct {
int y;
int x;
} h;
core_reloc_mods_substruct_t g;
};
typedef int int1_t;
typedef int1_t int2_t;
typedef int2_t int3_t;
typedef int arr1_t[5];
typedef arr1_t arr2_t;
typedef arr2_t arr3_t;
typedef arr3_t arr4_t;
typedef const char * const volatile restrict fancy_char_ptr_t;
typedef core_reloc_mods_substruct_t core_reloc_mods_substruct_tt;
/* we need more typedefs */
struct core_reloc_mods___typedefs {
core_reloc_mods_substruct_tt g;
core_reloc_mods_substruct_tt h;
arr4_t f;
arr4_t e;
fancy_char_ptr_t d;
fancy_char_ptr_t c;
int3_t b;
int3_t a;
};
/*
* PTR_AS_ARR
*/
struct core_reloc_ptr_as_arr {
int a;
};
struct core_reloc_ptr_as_arr___diff_sz {
int :32; /* padding */
char __some_more_padding;
int a;
};
/*
* INTS
*/
struct core_reloc_ints {
uint8_t u8_field;
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field;
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
/* signed/unsigned types swap */
struct core_reloc_ints___reverse_sign {
int8_t u8_field;
uint8_t s8_field;
int16_t u16_field;
uint16_t s16_field;
int32_t u32_field;
uint32_t s32_field;
int64_t u64_field;
uint64_t s64_field;
};
struct core_reloc_ints___bool {
bool u8_field; /* bool instead of uint8 */
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field;
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
struct core_reloc_ints___err_bitfield {
uint8_t u8_field;
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field: 32; /* bitfields are not supported */
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
struct core_reloc_ints___err_wrong_sz_8 {
uint16_t u8_field; /* not 8-bit anymore */
int16_t s8_field; /* not 8-bit anymore */
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field;
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
struct core_reloc_ints___err_wrong_sz_16 {
uint8_t u8_field;
int8_t s8_field;
uint32_t u16_field; /* not 16-bit anymore */
int32_t s16_field; /* not 16-bit anymore */
uint32_t u32_field;
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
struct core_reloc_ints___err_wrong_sz_32 {
uint8_t u8_field;
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint64_t u32_field; /* not 32-bit anymore */
int64_t s32_field; /* not 32-bit anymore */
uint64_t u64_field;
int64_t s64_field;
};
struct core_reloc_ints___err_wrong_sz_64 {
uint8_t u8_field;
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field;
int32_t s32_field;
uint32_t u64_field; /* not 64-bit anymore */
int32_t s64_field; /* not 64-bit anymore */
};
/*
* MISC
*/
struct core_reloc_misc_output {
int a, b, c;
};
struct core_reloc_misc___a {
int a1;
int a2;
};
struct core_reloc_misc___b {
int b1;
int b2;
};
/* this one extends core_reloc_misc_extensible struct from BPF prog */
struct core_reloc_misc_extensible {
int a;
int b;
int c;
int d;
};
tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_arrays_output {
int a2;
char b123;
int c1c;
int d00d;
};
struct core_reloc_arrays_substruct {
int c;
int d;
};
struct core_reloc_arrays {
int a[5];
char b[2][3][4];
struct core_reloc_arrays_substruct c[3];
struct core_reloc_arrays_substruct d[1][2];
};
SEC("raw_tracepoint/sys_enter")
int test_core_arrays(void *ctx)
{
struct core_reloc_arrays *in = (void *)&data.in;
struct core_reloc_arrays_output *out = (void *)&data.out;
/* in->a[2] */
if (BPF_CORE_READ(&out->a2, &in->a[2]))
return 1;
/* in->b[1][2][3] */
if (BPF_CORE_READ(&out->b123, &in->b[1][2][3]))
return 1;
/* in->c[1].c */
if (BPF_CORE_READ(&out->c1c, &in->c[1].c))
return 1;
/* in->d[0][0].d */
if (BPF_CORE_READ(&out->d00d, &in->d[0][0].d))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_flavors {
int a;
int b;
int c;
};
/* local flavor with reversed layout */
struct core_reloc_flavors___reversed {
int c;
int b;
int a;
};
/* local flavor with nested/overlapping layout */
struct core_reloc_flavors___weird {
struct {
int b;
};
/* a and c overlap in local flavor, but this should still work
* correctly with target original flavor
*/
union {
int a;
int c;
};
};
SEC("raw_tracepoint/sys_enter")
int test_core_flavors(void *ctx)
{
struct core_reloc_flavors *in_orig = (void *)&data.in;
struct core_reloc_flavors___reversed *in_rev = (void *)&data.in;
struct core_reloc_flavors___weird *in_weird = (void *)&data.in;
struct core_reloc_flavors *out = (void *)&data.out;
/* read a using weird layout */
if (BPF_CORE_READ(&out->a, &in_weird->a))
return 1;
/* read b using reversed layout */
if (BPF_CORE_READ(&out->b, &in_rev->b))
return 1;
/* read c using original layout */
if (BPF_CORE_READ(&out->c, &in_orig->c))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_ints.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_ints {
uint8_t u8_field;
int8_t s8_field;
uint16_t u16_field;
int16_t s16_field;
uint32_t u32_field;
int32_t s32_field;
uint64_t u64_field;
int64_t s64_field;
};
SEC("raw_tracepoint/sys_enter")
int test_core_ints(void *ctx)
{
struct core_reloc_ints *in = (void *)&data.in;
struct core_reloc_ints *out = (void *)&data.out;
if (BPF_CORE_READ(&out->u8_field, &in->u8_field) ||
BPF_CORE_READ(&out->s8_field, &in->s8_field) ||
BPF_CORE_READ(&out->u16_field, &in->u16_field) ||
BPF_CORE_READ(&out->s16_field, &in->s16_field) ||
BPF_CORE_READ(&out->u32_field, &in->u32_field) ||
BPF_CORE_READ(&out->s32_field, &in->s32_field) ||
BPF_CORE_READ(&out->u64_field, &in->u64_field) ||
BPF_CORE_READ(&out->s64_field, &in->s64_field))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct task_struct {
int pid;
int tgid;
};
SEC("raw_tracepoint/sys_enter")
int test_core_kernel(void *ctx)
{
struct task_struct *task = (void *)bpf_get_current_task();
uint64_t pid_tgid = bpf_get_current_pid_tgid();
int pid, tgid;
if (BPF_CORE_READ(&pid, &task->pid) ||
BPF_CORE_READ(&tgid, &task->tgid))
return 1;
/* validate pid + tgid matches */
data.out[0] = (((uint64_t)pid << 32) | tgid) == pid_tgid;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_misc.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_misc_output {
int a, b, c;
};
struct core_reloc_misc___a {
int a1;
int a2;
};
struct core_reloc_misc___b {
int b1;
int b2;
};
/* fixed two first members, can be extended with new fields */
struct core_reloc_misc_extensible {
int a;
int b;
};
SEC("raw_tracepoint/sys_enter")
int test_core_misc(void *ctx)
{
struct core_reloc_misc___a *in_a = (void *)&data.in;
struct core_reloc_misc___b *in_b = (void *)&data.in;
struct core_reloc_misc_extensible *in_ext = (void *)&data.in;
struct core_reloc_misc_output *out = (void *)&data.out;
/* record two different relocations with the same accessor string */
if (BPF_CORE_READ(&out->a, &in_a->a1) || /* accessor: 0:0 */
BPF_CORE_READ(&out->b, &in_b->b1)) /* accessor: 0:0 */
return 1;
/* Validate relocations capture array-only accesses for structs with
* fixed header, but with potentially extendable tail. This will read
* first 4 bytes of 2nd element of in_ext array of potentially
* variably sized struct core_reloc_misc_extensible. */
if (BPF_CORE_READ(&out->c, &in_ext[2])) /* accessor: 2 */
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_mods.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_mods_output {
int a, b, c, d, e, f, g, h;
};
typedef const int int_t;
typedef const char *char_ptr_t;
typedef const int arr_t[7];
struct core_reloc_mods_substruct {
int x;
int y;
};
typedef struct {
int x;
int y;
} core_reloc_mods_substruct_t;
struct core_reloc_mods {
int a;
int_t b;
char *c;
char_ptr_t d;
int e[3];
arr_t f;
struct core_reloc_mods_substruct g;
core_reloc_mods_substruct_t h;
};
SEC("raw_tracepoint/sys_enter")
int test_core_mods(void *ctx)
{
struct core_reloc_mods *in = (void *)&data.in;
struct core_reloc_mods_output *out = (void *)&data.out;
if (BPF_CORE_READ(&out->a, &in->a) ||
BPF_CORE_READ(&out->b, &in->b) ||
BPF_CORE_READ(&out->c, &in->c) ||
BPF_CORE_READ(&out->d, &in->d) ||
BPF_CORE_READ(&out->e, &in->e[2]) ||
BPF_CORE_READ(&out->f, &in->f[1]) ||
BPF_CORE_READ(&out->g, &in->g.x) ||
BPF_CORE_READ(&out->h, &in->h.y))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_nesting.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_nesting_substruct {
int a;
};
union core_reloc_nesting_subunion {
int b;
};
/* int a.a.a and b.b.b accesses */
struct core_reloc_nesting {
union {
struct core_reloc_nesting_substruct a;
} a;
struct {
union core_reloc_nesting_subunion b;
} b;
};
SEC("raw_tracepoint/sys_enter")
int test_core_nesting(void *ctx)
{
struct core_reloc_nesting *in = (void *)&data.in;
struct core_reloc_nesting *out = (void *)&data.out;
if (BPF_CORE_READ(&out->a.a.a, &in->a.a.a))
return 1;
if (BPF_CORE_READ(&out->b.b.b, &in->b.b.b))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_primitives.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
enum core_reloc_primitives_enum {
A = 0,
B = 1,
};
struct core_reloc_primitives {
char a;
int b;
enum core_reloc_primitives_enum c;
void *d;
int (*f)(const char *);
};
SEC("raw_tracepoint/sys_enter")
int test_core_primitives(void *ctx)
{
struct core_reloc_primitives *in = (void *)&data.in;
struct core_reloc_primitives *out = (void *)&data.out;
if (BPF_CORE_READ(&out->a, &in->a) ||
BPF_CORE_READ(&out->b, &in->b) ||
BPF_CORE_READ(&out->c, &in->c) ||
BPF_CORE_READ(&out->d, &in->d) ||
BPF_CORE_READ(&out->f, &in->f))
return 1;
return 0;
}
tools/testing/selftests/bpf/progs/test_core_reloc_ptr_as_arr.c 0 → 100644
View file @ 726e333f
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
static volatile struct data {
char in[256];
char out[256];
} data;
struct core_reloc_ptr_as_arr {
int a;
};
SEC("raw_tracepoint/sys_enter")
int test_core_ptr_as_arr(void *ctx)
{
struct core_reloc_ptr_as_arr *in = (void *)&data.in;
struct core_reloc_ptr_as_arr *out = (void *)&data.out;
if (BPF_CORE_READ(&out->a, &in[2].a))
return 1;
return 0;
}
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