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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/lib/bpf/libbpf_internal.h
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/lib/bpf/libbpf_internal.h')
-rw-r--r--tools/lib/bpf/libbpf_internal.h579
1 files changed, 579 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
new file mode 100644
index 000000000..377642ff5
--- /dev/null
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -0,0 +1,579 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+
+/*
+ * Internal libbpf helpers.
+ *
+ * Copyright (c) 2019 Facebook
+ */
+
+#ifndef __LIBBPF_LIBBPF_INTERNAL_H
+#define __LIBBPF_LIBBPF_INTERNAL_H
+
+#include <stdlib.h>
+#include <limits.h>
+#include <errno.h>
+#include <linux/err.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include "relo_core.h"
+
+/* make sure libbpf doesn't use kernel-only integer typedefs */
+#pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
+
+/* prevent accidental re-addition of reallocarray() */
+#pragma GCC poison reallocarray
+
+#include "libbpf.h"
+#include "btf.h"
+
+#ifndef EM_BPF
+#define EM_BPF 247
+#endif
+
+#ifndef R_BPF_64_64
+#define R_BPF_64_64 1
+#endif
+#ifndef R_BPF_64_ABS64
+#define R_BPF_64_ABS64 2
+#endif
+#ifndef R_BPF_64_ABS32
+#define R_BPF_64_ABS32 3
+#endif
+#ifndef R_BPF_64_32
+#define R_BPF_64_32 10
+#endif
+
+#ifndef SHT_LLVM_ADDRSIG
+#define SHT_LLVM_ADDRSIG 0x6FFF4C03
+#endif
+
+/* if libelf is old and doesn't support mmap(), fall back to read() */
+#ifndef ELF_C_READ_MMAP
+#define ELF_C_READ_MMAP ELF_C_READ
+#endif
+
+/* Older libelf all end up in this expression, for both 32 and 64 bit */
+#ifndef ELF64_ST_VISIBILITY
+#define ELF64_ST_VISIBILITY(o) ((o) & 0x03)
+#endif
+
+#define BTF_INFO_ENC(kind, kind_flag, vlen) \
+ ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
+#define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type)
+#define BTF_INT_ENC(encoding, bits_offset, nr_bits) \
+ ((encoding) << 24 | (bits_offset) << 16 | (nr_bits))
+#define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \
+ BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \
+ BTF_INT_ENC(encoding, bits_offset, bits)
+#define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset)
+#define BTF_PARAM_ENC(name, type) (name), (type)
+#define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
+#define BTF_TYPE_FLOAT_ENC(name, sz) \
+ BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
+#define BTF_TYPE_DECL_TAG_ENC(value, type, component_idx) \
+ BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_DECL_TAG, 0, 0), type), (component_idx)
+#define BTF_TYPE_TYPE_TAG_ENC(value, type) \
+ BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_TYPE_TAG, 0, 0), type)
+
+#ifndef likely
+#define likely(x) __builtin_expect(!!(x), 1)
+#endif
+#ifndef unlikely
+#define unlikely(x) __builtin_expect(!!(x), 0)
+#endif
+#ifndef min
+# define min(x, y) ((x) < (y) ? (x) : (y))
+#endif
+#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
+#ifndef __alias
+#define __alias(symbol) __attribute__((alias(#symbol)))
+#endif
+
+/* Check whether a string `str` has prefix `pfx`, regardless if `pfx` is
+ * a string literal known at compilation time or char * pointer known only at
+ * runtime.
+ */
+#define str_has_pfx(str, pfx) \
+ (strncmp(str, pfx, __builtin_constant_p(pfx) ? sizeof(pfx) - 1 : strlen(pfx)) == 0)
+
+/* suffix check */
+static inline bool str_has_sfx(const char *str, const char *sfx)
+{
+ size_t str_len = strlen(str);
+ size_t sfx_len = strlen(sfx);
+
+ if (sfx_len > str_len)
+ return false;
+ return strcmp(str + str_len - sfx_len, sfx) == 0;
+}
+
+/* Symbol versioning is different between static and shared library.
+ * Properly versioned symbols are needed for shared library, but
+ * only the symbol of the new version is needed for static library.
+ * Starting with GNU C 10, use symver attribute instead of .symver assembler
+ * directive, which works better with GCC LTO builds.
+ */
+#if defined(SHARED) && defined(__GNUC__) && __GNUC__ >= 10
+
+#define DEFAULT_VERSION(internal_name, api_name, version) \
+ __attribute__((symver(#api_name "@@" #version)))
+#define COMPAT_VERSION(internal_name, api_name, version) \
+ __attribute__((symver(#api_name "@" #version)))
+
+#elif defined(SHARED)
+
+#define COMPAT_VERSION(internal_name, api_name, version) \
+ asm(".symver " #internal_name "," #api_name "@" #version);
+#define DEFAULT_VERSION(internal_name, api_name, version) \
+ asm(".symver " #internal_name "," #api_name "@@" #version);
+
+#else /* !SHARED */
+
+#define COMPAT_VERSION(internal_name, api_name, version)
+#define DEFAULT_VERSION(internal_name, api_name, version) \
+ extern typeof(internal_name) api_name \
+ __attribute__((alias(#internal_name)));
+
+#endif
+
+extern void libbpf_print(enum libbpf_print_level level,
+ const char *format, ...)
+ __attribute__((format(printf, 2, 3)));
+
+#define __pr(level, fmt, ...) \
+do { \
+ libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__); \
+} while (0)
+
+#define pr_warn(fmt, ...) __pr(LIBBPF_WARN, fmt, ##__VA_ARGS__)
+#define pr_info(fmt, ...) __pr(LIBBPF_INFO, fmt, ##__VA_ARGS__)
+#define pr_debug(fmt, ...) __pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__)
+
+#ifndef __has_builtin
+#define __has_builtin(x) 0
+#endif
+
+struct bpf_link {
+ int (*detach)(struct bpf_link *link);
+ void (*dealloc)(struct bpf_link *link);
+ char *pin_path; /* NULL, if not pinned */
+ int fd; /* hook FD, -1 if not applicable */
+ bool disconnected;
+};
+
+/*
+ * Re-implement glibc's reallocarray() for libbpf internal-only use.
+ * reallocarray(), unfortunately, is not available in all versions of glibc,
+ * so requires extra feature detection and using reallocarray() stub from
+ * <tools/libc_compat.h> and COMPAT_NEED_REALLOCARRAY. All this complicates
+ * build of libbpf unnecessarily and is just a maintenance burden. Instead,
+ * it's trivial to implement libbpf-specific internal version and use it
+ * throughout libbpf.
+ */
+static inline void *libbpf_reallocarray(void *ptr, size_t nmemb, size_t size)
+{
+ size_t total;
+
+#if __has_builtin(__builtin_mul_overflow)
+ if (unlikely(__builtin_mul_overflow(nmemb, size, &total)))
+ return NULL;
+#else
+ if (size == 0 || nmemb > ULONG_MAX / size)
+ return NULL;
+ total = nmemb * size;
+#endif
+ return realloc(ptr, total);
+}
+
+/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
+ * is zero-terminated string no matter what (unless sz == 0, in which case
+ * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
+ * in what is returned. Given this is internal helper, it's trivial to extend
+ * this, when necessary. Use this instead of strncpy inside libbpf source code.
+ */
+static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz)
+{
+ size_t i;
+
+ if (sz == 0)
+ return;
+
+ sz--;
+ for (i = 0; i < sz && src[i]; i++)
+ dst[i] = src[i];
+ dst[i] = '\0';
+}
+
+__u32 get_kernel_version(void);
+
+struct btf;
+struct btf_type;
+
+struct btf_type *btf_type_by_id(const struct btf *btf, __u32 type_id);
+const char *btf_kind_str(const struct btf_type *t);
+const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id);
+
+static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t)
+{
+ return (enum btf_func_linkage)(int)btf_vlen(t);
+}
+
+static inline __u32 btf_type_info(int kind, int vlen, int kflag)
+{
+ return (kflag << 31) | (kind << 24) | vlen;
+}
+
+enum map_def_parts {
+ MAP_DEF_MAP_TYPE = 0x001,
+ MAP_DEF_KEY_TYPE = 0x002,
+ MAP_DEF_KEY_SIZE = 0x004,
+ MAP_DEF_VALUE_TYPE = 0x008,
+ MAP_DEF_VALUE_SIZE = 0x010,
+ MAP_DEF_MAX_ENTRIES = 0x020,
+ MAP_DEF_MAP_FLAGS = 0x040,
+ MAP_DEF_NUMA_NODE = 0x080,
+ MAP_DEF_PINNING = 0x100,
+ MAP_DEF_INNER_MAP = 0x200,
+ MAP_DEF_MAP_EXTRA = 0x400,
+
+ MAP_DEF_ALL = 0x7ff, /* combination of all above */
+};
+
+struct btf_map_def {
+ enum map_def_parts parts;
+ __u32 map_type;
+ __u32 key_type_id;
+ __u32 key_size;
+ __u32 value_type_id;
+ __u32 value_size;
+ __u32 max_entries;
+ __u32 map_flags;
+ __u32 numa_node;
+ __u32 pinning;
+ __u64 map_extra;
+};
+
+int parse_btf_map_def(const char *map_name, struct btf *btf,
+ const struct btf_type *def_t, bool strict,
+ struct btf_map_def *map_def, struct btf_map_def *inner_def);
+
+void *libbpf_add_mem(void **data, size_t *cap_cnt, size_t elem_sz,
+ size_t cur_cnt, size_t max_cnt, size_t add_cnt);
+int libbpf_ensure_mem(void **data, size_t *cap_cnt, size_t elem_sz, size_t need_cnt);
+
+static inline bool libbpf_is_mem_zeroed(const char *p, ssize_t len)
+{
+ while (len > 0) {
+ if (*p)
+ return false;
+ p++;
+ len--;
+ }
+ return true;
+}
+
+static inline bool libbpf_validate_opts(const char *opts,
+ size_t opts_sz, size_t user_sz,
+ const char *type_name)
+{
+ if (user_sz < sizeof(size_t)) {
+ pr_warn("%s size (%zu) is too small\n", type_name, user_sz);
+ return false;
+ }
+ if (!libbpf_is_mem_zeroed(opts + opts_sz, (ssize_t)user_sz - opts_sz)) {
+ pr_warn("%s has non-zero extra bytes\n", type_name);
+ return false;
+ }
+ return true;
+}
+
+#define OPTS_VALID(opts, type) \
+ (!(opts) || libbpf_validate_opts((const char *)opts, \
+ offsetofend(struct type, \
+ type##__last_field), \
+ (opts)->sz, #type))
+#define OPTS_HAS(opts, field) \
+ ((opts) && opts->sz >= offsetofend(typeof(*(opts)), field))
+#define OPTS_GET(opts, field, fallback_value) \
+ (OPTS_HAS(opts, field) ? (opts)->field : fallback_value)
+#define OPTS_SET(opts, field, value) \
+ do { \
+ if (OPTS_HAS(opts, field)) \
+ (opts)->field = value; \
+ } while (0)
+
+#define OPTS_ZEROED(opts, last_nonzero_field) \
+({ \
+ ssize_t __off = offsetofend(typeof(*(opts)), last_nonzero_field); \
+ !(opts) || libbpf_is_mem_zeroed((const void *)opts + __off, \
+ (opts)->sz - __off); \
+})
+
+enum kern_feature_id {
+ /* v4.14: kernel support for program & map names. */
+ FEAT_PROG_NAME,
+ /* v5.2: kernel support for global data sections. */
+ FEAT_GLOBAL_DATA,
+ /* BTF support */
+ FEAT_BTF,
+ /* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */
+ FEAT_BTF_FUNC,
+ /* BTF_KIND_VAR and BTF_KIND_DATASEC support */
+ FEAT_BTF_DATASEC,
+ /* BTF_FUNC_GLOBAL is supported */
+ FEAT_BTF_GLOBAL_FUNC,
+ /* BPF_F_MMAPABLE is supported for arrays */
+ FEAT_ARRAY_MMAP,
+ /* kernel support for expected_attach_type in BPF_PROG_LOAD */
+ FEAT_EXP_ATTACH_TYPE,
+ /* bpf_probe_read_{kernel,user}[_str] helpers */
+ FEAT_PROBE_READ_KERN,
+ /* BPF_PROG_BIND_MAP is supported */
+ FEAT_PROG_BIND_MAP,
+ /* Kernel support for module BTFs */
+ FEAT_MODULE_BTF,
+ /* BTF_KIND_FLOAT support */
+ FEAT_BTF_FLOAT,
+ /* BPF perf link support */
+ FEAT_PERF_LINK,
+ /* BTF_KIND_DECL_TAG support */
+ FEAT_BTF_DECL_TAG,
+ /* BTF_KIND_TYPE_TAG support */
+ FEAT_BTF_TYPE_TAG,
+ /* memcg-based accounting for BPF maps and progs */
+ FEAT_MEMCG_ACCOUNT,
+ /* BPF cookie (bpf_get_attach_cookie() BPF helper) support */
+ FEAT_BPF_COOKIE,
+ /* BTF_KIND_ENUM64 support and BTF_KIND_ENUM kflag support */
+ FEAT_BTF_ENUM64,
+ /* Kernel uses syscall wrapper (CONFIG_ARCH_HAS_SYSCALL_WRAPPER) */
+ FEAT_SYSCALL_WRAPPER,
+ __FEAT_CNT,
+};
+
+int probe_memcg_account(void);
+bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id);
+int bump_rlimit_memlock(void);
+
+int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz);
+int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
+int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
+ const char *str_sec, size_t str_len);
+int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level);
+
+struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf);
+void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type,
+ const char **prefix, int *kind);
+
+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;
+ /* optional (maintained internally by libbpf) mapping between .BTF.ext
+ * section and corresponding ELF section. This is used to join
+ * information like CO-RE relocation records with corresponding BPF
+ * programs defined in ELF sections
+ */
+ __u32 *sec_idxs;
+ int sec_cnt;
+};
+
+#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)
+
+/*
+ * The .BTF.ext ELF section layout defined as
+ * struct btf_ext_header
+ * func_info subsection
+ *
+ * The func_info subsection layout:
+ * record size for struct bpf_func_info in the func_info subsection
+ * struct btf_sec_func_info for section #1
+ * a list of bpf_func_info records for section #1
+ * where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
+ * but may not be identical
+ * struct btf_sec_func_info for section #2
+ * a list of bpf_func_info records for section #2
+ * ......
+ *
+ * Note that the bpf_func_info record size in .BTF.ext may not
+ * be the same as the one defined in include/uapi/linux/bpf.h.
+ * The loader should ensure that record_size meets minimum
+ * requirement and pass the record as is to the kernel. The
+ * kernel will handle the func_info properly based on its contents.
+ */
+struct btf_ext_header {
+ __u16 magic;
+ __u8 version;
+ __u8 flags;
+ __u32 hdr_len;
+
+ /* All offsets are in bytes relative to the end of this header */
+ __u32 func_info_off;
+ __u32 func_info_len;
+ __u32 line_info_off;
+ __u32 line_info_len;
+
+ /* optional part of .BTF.ext header */
+ __u32 core_relo_off;
+ __u32 core_relo_len;
+};
+
+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 core_relo_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[];
+};
+
+/* 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;
+};
+
+
+typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx);
+typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx);
+int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx);
+int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx);
+int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx);
+int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx);
+__s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name,
+ __u32 kind);
+
+typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type,
+ const char *sym_name, void *ctx);
+
+int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *arg);
+
+/* handle direct returned errors */
+static inline int libbpf_err(int ret)
+{
+ if (ret < 0)
+ errno = -ret;
+ return ret;
+}
+
+/* handle errno-based (e.g., syscall or libc) errors according to libbpf's
+ * strict mode settings
+ */
+static inline int libbpf_err_errno(int ret)
+{
+ /* errno is already assumed to be set on error */
+ return ret < 0 ? -errno : ret;
+}
+
+/* handle error for pointer-returning APIs, err is assumed to be < 0 always */
+static inline void *libbpf_err_ptr(int err)
+{
+ /* set errno on error, this doesn't break anything */
+ errno = -err;
+ return NULL;
+}
+
+/* handle pointer-returning APIs' error handling */
+static inline void *libbpf_ptr(void *ret)
+{
+ /* set errno on error, this doesn't break anything */
+ if (IS_ERR(ret))
+ errno = -PTR_ERR(ret);
+
+ return IS_ERR(ret) ? NULL : ret;
+}
+
+static inline bool str_is_empty(const char *s)
+{
+ return !s || !s[0];
+}
+
+static inline bool is_ldimm64_insn(struct bpf_insn *insn)
+{
+ return insn->code == (BPF_LD | BPF_IMM | BPF_DW);
+}
+
+/* if fd is stdin, stdout, or stderr, dup to a fd greater than 2
+ * Takes ownership of the fd passed in, and closes it if calling
+ * fcntl(fd, F_DUPFD_CLOEXEC, 3).
+ */
+static inline int ensure_good_fd(int fd)
+{
+ int old_fd = fd, saved_errno;
+
+ if (fd < 0)
+ return fd;
+ if (fd < 3) {
+ fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
+ saved_errno = errno;
+ close(old_fd);
+ if (fd < 0) {
+ pr_warn("failed to dup FD %d to FD > 2: %d\n", old_fd, -saved_errno);
+ errno = saved_errno;
+ }
+ }
+ return fd;
+}
+
+/* The following two functions are exposed to bpftool */
+int bpf_core_add_cands(struct bpf_core_cand *local_cand,
+ size_t local_essent_len,
+ const struct btf *targ_btf,
+ const char *targ_btf_name,
+ int targ_start_id,
+ struct bpf_core_cand_list *cands);
+void bpf_core_free_cands(struct bpf_core_cand_list *cands);
+
+struct usdt_manager *usdt_manager_new(struct bpf_object *obj);
+void usdt_manager_free(struct usdt_manager *man);
+struct bpf_link * usdt_manager_attach_usdt(struct usdt_manager *man,
+ const struct bpf_program *prog,
+ pid_t pid, const char *path,
+ const char *usdt_provider, const char *usdt_name,
+ __u64 usdt_cookie);
+
+static inline bool is_pow_of_2(size_t x)
+{
+ return x && (x & (x - 1)) == 0;
+}
+
+#define PROG_LOAD_ATTEMPTS 5
+int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts);
+
+#endif /* __LIBBPF_LIBBPF_INTERNAL_H */