diff options
Diffstat (limited to 'tools/bpf/resolve_btfids')
| -rw-r--r-- | tools/bpf/resolve_btfids/.gitignore | 3 | ||||
| -rw-r--r-- | tools/bpf/resolve_btfids/Build | 12 | ||||
| -rw-r--r-- | tools/bpf/resolve_btfids/Makefile | 112 | ||||
| -rw-r--r-- | tools/bpf/resolve_btfids/main.c | 783 |
4 files changed, 910 insertions, 0 deletions
diff --git a/tools/bpf/resolve_btfids/.gitignore b/tools/bpf/resolve_btfids/.gitignore new file mode 100644 index 000000000..16913fffc --- /dev/null +++ b/tools/bpf/resolve_btfids/.gitignore @@ -0,0 +1,3 @@ +/fixdep +/resolve_btfids +/libbpf/ diff --git a/tools/bpf/resolve_btfids/Build b/tools/bpf/resolve_btfids/Build new file mode 100644 index 000000000..077de3829 --- /dev/null +++ b/tools/bpf/resolve_btfids/Build @@ -0,0 +1,12 @@ +hostprogs := resolve_btfids + +resolve_btfids-y += main.o +resolve_btfids-y += rbtree.o +resolve_btfids-y += zalloc.o +resolve_btfids-y += string.o +resolve_btfids-y += ctype.o +resolve_btfids-y += str_error_r.o + +$(OUTPUT)%.o: ../../lib/%.c FORCE + $(call rule_mkdir) + $(call if_changed_dep,host_cc_o_c) diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile new file mode 100644 index 000000000..4b8079f29 --- /dev/null +++ b/tools/bpf/resolve_btfids/Makefile @@ -0,0 +1,112 @@ +# SPDX-License-Identifier: GPL-2.0-only +include ../../scripts/Makefile.include +include ../../scripts/Makefile.arch + +srctree := $(abspath $(CURDIR)/../../../) + +ifeq ($(V),1) + Q = + msg = +else + Q = @ + ifeq ($(silent),1) + msg = + else + msg = @printf ' %-8s %s%s\n' "$(1)" "$(notdir $(2))" "$(if $(3), $(3))"; + endif + MAKEFLAGS=--no-print-directory +endif + +# Overrides for the prepare step libraries. +HOST_OVERRIDES := AR="$(HOSTAR)" CC="$(HOSTCC)" LD="$(HOSTLD)" ARCH="$(HOSTARCH)" \ + CROSS_COMPILE="" EXTRA_CFLAGS="$(HOSTCFLAGS)" + +RM ?= rm +HOSTCC ?= gcc +HOSTLD ?= ld +HOSTAR ?= ar +CROSS_COMPILE = + +OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ + +LIBBPF_SRC := $(srctree)/tools/lib/bpf/ +SUBCMD_SRC := $(srctree)/tools/lib/subcmd/ + +BPFOBJ := $(OUTPUT)/libbpf/libbpf.a +LIBBPF_OUT := $(abspath $(dir $(BPFOBJ)))/ +SUBCMDOBJ := $(OUTPUT)/libsubcmd/libsubcmd.a +SUBCMD_OUT := $(abspath $(dir $(SUBCMDOBJ)))/ + +LIBBPF_DESTDIR := $(LIBBPF_OUT) +LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)include + +SUBCMD_DESTDIR := $(SUBCMD_OUT) +SUBCMD_INCLUDE := $(SUBCMD_DESTDIR)include + +BINARY := $(OUTPUT)/resolve_btfids +BINARY_IN := $(BINARY)-in.o + +all: $(BINARY) + +prepare: $(BPFOBJ) $(SUBCMDOBJ) + +$(OUTPUT) $(OUTPUT)/libsubcmd $(LIBBPF_OUT): + $(call msg,MKDIR,,$@) + $(Q)mkdir -p $(@) + +$(SUBCMDOBJ): fixdep FORCE | $(OUTPUT)/libsubcmd + $(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(SUBCMD_OUT) \ + DESTDIR=$(SUBCMD_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \ + $(abspath $@) install_headers + +$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUT) + $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(LIBBPF_OUT) \ + DESTDIR=$(LIBBPF_DESTDIR) $(HOST_OVERRIDES) prefix= subdir= \ + $(abspath $@) install_headers + +LIBELF_FLAGS := $(shell $(HOSTPKG_CONFIG) libelf --cflags 2>/dev/null) +LIBELF_LIBS := $(shell $(HOSTPKG_CONFIG) libelf --libs 2>/dev/null || echo -lelf) + +HOSTCFLAGS_resolve_btfids += -g \ + -I$(srctree)/tools/include \ + -I$(srctree)/tools/include/uapi \ + -I$(LIBBPF_INCLUDE) \ + -I$(SUBCMD_INCLUDE) \ + $(LIBELF_FLAGS) + +LIBS = $(LIBELF_LIBS) -lz + +export srctree OUTPUT HOSTCFLAGS_resolve_btfids Q HOSTCC HOSTLD HOSTAR +include $(srctree)/tools/build/Makefile.include + +$(BINARY_IN): fixdep FORCE prepare | $(OUTPUT) + $(Q)$(MAKE) $(build)=resolve_btfids + +$(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN) + $(call msg,LINK,$@) + $(Q)$(HOSTCC) $(BINARY_IN) $(KBUILD_HOSTLDFLAGS) -o $@ $(BPFOBJ) $(SUBCMDOBJ) $(LIBS) + +clean_objects := $(wildcard $(OUTPUT)/*.o \ + $(OUTPUT)/.*.o.cmd \ + $(OUTPUT)/.*.o.d \ + $(LIBBPF_OUT) \ + $(LIBBPF_DESTDIR) \ + $(SUBCMD_OUT) \ + $(SUBCMD_DESTDIR) \ + $(OUTPUT)/resolve_btfids) + +ifneq ($(clean_objects),) +clean: fixdep-clean + $(call msg,CLEAN,$(BINARY)) + $(Q)$(RM) -rf $(clean_objects) +else +clean: +endif + +tags: + $(call msg,GEN,,tags) + $(Q)ctags -R . $(LIBBPF_SRC) $(SUBCMD_SRC) + +FORCE: + +.PHONY: all FORCE clean tags prepare diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c new file mode 100644 index 000000000..770581740 --- /dev/null +++ b/tools/bpf/resolve_btfids/main.c @@ -0,0 +1,783 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) + +/* + * resolve_btfids scans Elf object for .BTF_ids section and resolves + * its symbols with BTF ID values. + * + * Each symbol points to 4 bytes data and is expected to have + * following name syntax: + * + * __BTF_ID__<type>__<symbol>[__<id>] + * + * type is: + * + * func - lookup BTF_KIND_FUNC symbol with <symbol> name + * and store its ID into the data: + * + * __BTF_ID__func__vfs_close__1: + * .zero 4 + * + * struct - lookup BTF_KIND_STRUCT symbol with <symbol> name + * and store its ID into the data: + * + * __BTF_ID__struct__sk_buff__1: + * .zero 4 + * + * union - lookup BTF_KIND_UNION symbol with <symbol> name + * and store its ID into the data: + * + * __BTF_ID__union__thread_union__1: + * .zero 4 + * + * typedef - lookup BTF_KIND_TYPEDEF symbol with <symbol> name + * and store its ID into the data: + * + * __BTF_ID__typedef__pid_t__1: + * .zero 4 + * + * set - store symbol size into first 4 bytes and sort following + * ID list + * + * __BTF_ID__set__list: + * .zero 4 + * list: + * __BTF_ID__func__vfs_getattr__3: + * .zero 4 + * __BTF_ID__func__vfs_fallocate__4: + * .zero 4 + * + * set8 - store symbol size into first 4 bytes and sort following + * ID list + * + * __BTF_ID__set8__list: + * .zero 8 + * list: + * __BTF_ID__func__vfs_getattr__3: + * .zero 4 + * .word (1 << 0) | (1 << 2) + * __BTF_ID__func__vfs_fallocate__5: + * .zero 4 + * .word (1 << 3) | (1 << 1) | (1 << 2) + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <stdlib.h> +#include <libelf.h> +#include <gelf.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <linux/rbtree.h> +#include <linux/zalloc.h> +#include <linux/err.h> +#include <bpf/btf.h> +#include <bpf/libbpf.h> +#include <subcmd/parse-options.h> + +#define BTF_IDS_SECTION ".BTF_ids" +#define BTF_ID "__BTF_ID__" + +#define BTF_STRUCT "struct" +#define BTF_UNION "union" +#define BTF_TYPEDEF "typedef" +#define BTF_FUNC "func" +#define BTF_SET "set" +#define BTF_SET8 "set8" + +#define ADDR_CNT 100 + +struct btf_id { + struct rb_node rb_node; + char *name; + union { + int id; + int cnt; + }; + int addr_cnt; + bool is_set; + bool is_set8; + Elf64_Addr addr[ADDR_CNT]; +}; + +struct object { + const char *path; + const char *btf; + const char *base_btf_path; + + struct { + int fd; + Elf *elf; + Elf_Data *symbols; + Elf_Data *idlist; + int symbols_shndx; + int idlist_shndx; + size_t strtabidx; + unsigned long idlist_addr; + } efile; + + struct rb_root sets; + struct rb_root structs; + struct rb_root unions; + struct rb_root typedefs; + struct rb_root funcs; + + int nr_funcs; + int nr_structs; + int nr_unions; + int nr_typedefs; +}; + +static int verbose; + +static int eprintf(int level, int var, const char *fmt, ...) +{ + va_list args; + int ret = 0; + + if (var >= level) { + va_start(args, fmt); + ret = vfprintf(stderr, fmt, args); + va_end(args); + } + return ret; +} + +#ifndef pr_fmt +#define pr_fmt(fmt) fmt +#endif + +#define pr_debug(fmt, ...) \ + eprintf(1, verbose, pr_fmt(fmt), ##__VA_ARGS__) +#define pr_debugN(n, fmt, ...) \ + eprintf(n, verbose, pr_fmt(fmt), ##__VA_ARGS__) +#define pr_debug2(fmt, ...) pr_debugN(2, pr_fmt(fmt), ##__VA_ARGS__) +#define pr_err(fmt, ...) \ + eprintf(0, verbose, pr_fmt(fmt), ##__VA_ARGS__) +#define pr_info(fmt, ...) \ + eprintf(0, verbose, pr_fmt(fmt), ##__VA_ARGS__) + +static bool is_btf_id(const char *name) +{ + return name && !strncmp(name, BTF_ID, sizeof(BTF_ID) - 1); +} + +static struct btf_id *btf_id__find(struct rb_root *root, const char *name) +{ + struct rb_node *p = root->rb_node; + struct btf_id *id; + int cmp; + + while (p) { + id = rb_entry(p, struct btf_id, rb_node); + cmp = strcmp(id->name, name); + if (cmp < 0) + p = p->rb_left; + else if (cmp > 0) + p = p->rb_right; + else + return id; + } + return NULL; +} + +static struct btf_id * +btf_id__add(struct rb_root *root, char *name, bool unique) +{ + struct rb_node **p = &root->rb_node; + struct rb_node *parent = NULL; + struct btf_id *id; + int cmp; + + while (*p != NULL) { + parent = *p; + id = rb_entry(parent, struct btf_id, rb_node); + cmp = strcmp(id->name, name); + if (cmp < 0) + p = &(*p)->rb_left; + else if (cmp > 0) + p = &(*p)->rb_right; + else + return unique ? NULL : id; + } + + id = zalloc(sizeof(*id)); + if (id) { + pr_debug("adding symbol %s\n", name); + id->name = name; + rb_link_node(&id->rb_node, parent, p); + rb_insert_color(&id->rb_node, root); + } + return id; +} + +static char *get_id(const char *prefix_end) +{ + /* + * __BTF_ID__func__vfs_truncate__0 + * prefix_end = ^ + * pos = ^ + */ + int len = strlen(prefix_end); + int pos = sizeof("__") - 1; + char *p, *id; + + if (pos >= len) + return NULL; + + id = strdup(prefix_end + pos); + if (id) { + /* + * __BTF_ID__func__vfs_truncate__0 + * id = ^ + * + * cut the unique id part + */ + p = strrchr(id, '_'); + p--; + if (*p != '_') { + free(id); + return NULL; + } + *p = '\0'; + } + return id; +} + +static struct btf_id *add_set(struct object *obj, char *name, bool is_set8) +{ + /* + * __BTF_ID__set__name + * name = ^ + * id = ^ + */ + char *id = name + (is_set8 ? sizeof(BTF_SET8 "__") : sizeof(BTF_SET "__")) - 1; + int len = strlen(name); + + if (id >= name + len) { + pr_err("FAILED to parse set name: %s\n", name); + return NULL; + } + + return btf_id__add(&obj->sets, id, true); +} + +static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size) +{ + char *id; + + id = get_id(name + size); + if (!id) { + pr_err("FAILED to parse symbol name: %s\n", name); + return NULL; + } + + return btf_id__add(root, id, false); +} + +/* Older libelf.h and glibc elf.h might not yet define the ELF compression types. */ +#ifndef SHF_COMPRESSED +#define SHF_COMPRESSED (1 << 11) /* Section with compressed data. */ +#endif + +/* + * The data of compressed section should be aligned to 4 + * (for 32bit) or 8 (for 64 bit) bytes. The binutils ld + * sets sh_addralign to 1, which makes libelf fail with + * misaligned section error during the update: + * FAILED elf_update(WRITE): invalid section alignment + * + * While waiting for ld fix, we fix the compressed sections + * sh_addralign value manualy. + */ +static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh) +{ + int expected = gelf_getclass(elf) == ELFCLASS32 ? 4 : 8; + + if (!(sh->sh_flags & SHF_COMPRESSED)) + return 0; + + if (sh->sh_addralign == expected) + return 0; + + pr_debug2(" - fixing wrong alignment sh_addralign %u, expected %u\n", + sh->sh_addralign, expected); + + sh->sh_addralign = expected; + + if (gelf_update_shdr(scn, sh) == 0) { + pr_err("FAILED cannot update section header: %s\n", + elf_errmsg(-1)); + return -1; + } + return 0; +} + +static int elf_collect(struct object *obj) +{ + Elf_Scn *scn = NULL; + size_t shdrstrndx; + int idx = 0; + Elf *elf; + int fd; + + fd = open(obj->path, O_RDWR, 0666); + if (fd == -1) { + pr_err("FAILED cannot open %s: %s\n", + obj->path, strerror(errno)); + return -1; + } + + elf_version(EV_CURRENT); + + elf = elf_begin(fd, ELF_C_RDWR_MMAP, NULL); + if (!elf) { + close(fd); + pr_err("FAILED cannot create ELF descriptor: %s\n", + elf_errmsg(-1)); + return -1; + } + + obj->efile.fd = fd; + obj->efile.elf = elf; + + elf_flagelf(elf, ELF_C_SET, ELF_F_LAYOUT); + + if (elf_getshdrstrndx(elf, &shdrstrndx) != 0) { + pr_err("FAILED cannot get shdr str ndx\n"); + return -1; + } + + /* + * Scan all the elf sections and look for save data + * from .BTF_ids section and symbols. + */ + while ((scn = elf_nextscn(elf, scn)) != NULL) { + Elf_Data *data; + GElf_Shdr sh; + char *name; + + idx++; + if (gelf_getshdr(scn, &sh) != &sh) { + pr_err("FAILED get section(%d) header\n", idx); + return -1; + } + + name = elf_strptr(elf, shdrstrndx, sh.sh_name); + if (!name) { + pr_err("FAILED get section(%d) name\n", idx); + return -1; + } + + data = elf_getdata(scn, 0); + if (!data) { + pr_err("FAILED to get section(%d) data from %s\n", + idx, name); + return -1; + } + + pr_debug2("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", + idx, name, (unsigned long) data->d_size, + (int) sh.sh_link, (unsigned long) sh.sh_flags, + (int) sh.sh_type); + + if (sh.sh_type == SHT_SYMTAB) { + obj->efile.symbols = data; + obj->efile.symbols_shndx = idx; + obj->efile.strtabidx = sh.sh_link; + } else if (!strcmp(name, BTF_IDS_SECTION)) { + obj->efile.idlist = data; + obj->efile.idlist_shndx = idx; + obj->efile.idlist_addr = sh.sh_addr; + } + + if (compressed_section_fix(elf, scn, &sh)) + return -1; + } + + return 0; +} + +static int symbols_collect(struct object *obj) +{ + Elf_Scn *scn = NULL; + int n, i; + GElf_Shdr sh; + char *name; + + scn = elf_getscn(obj->efile.elf, obj->efile.symbols_shndx); + if (!scn) + return -1; + + if (gelf_getshdr(scn, &sh) != &sh) + return -1; + + n = sh.sh_size / sh.sh_entsize; + + /* + * Scan symbols and look for the ones starting with + * __BTF_ID__* over .BTF_ids section. + */ + for (i = 0; i < n; i++) { + char *prefix; + struct btf_id *id; + GElf_Sym sym; + + if (!gelf_getsym(obj->efile.symbols, i, &sym)) + return -1; + + if (sym.st_shndx != obj->efile.idlist_shndx) + continue; + + name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, + sym.st_name); + + if (!is_btf_id(name)) + continue; + + /* + * __BTF_ID__TYPE__vfs_truncate__0 + * prefix = ^ + */ + prefix = name + sizeof(BTF_ID) - 1; + + /* struct */ + if (!strncmp(prefix, BTF_STRUCT, sizeof(BTF_STRUCT) - 1)) { + obj->nr_structs++; + id = add_symbol(&obj->structs, prefix, sizeof(BTF_STRUCT) - 1); + /* union */ + } else if (!strncmp(prefix, BTF_UNION, sizeof(BTF_UNION) - 1)) { + obj->nr_unions++; + id = add_symbol(&obj->unions, prefix, sizeof(BTF_UNION) - 1); + /* typedef */ + } else if (!strncmp(prefix, BTF_TYPEDEF, sizeof(BTF_TYPEDEF) - 1)) { + obj->nr_typedefs++; + id = add_symbol(&obj->typedefs, prefix, sizeof(BTF_TYPEDEF) - 1); + /* func */ + } else if (!strncmp(prefix, BTF_FUNC, sizeof(BTF_FUNC) - 1)) { + obj->nr_funcs++; + id = add_symbol(&obj->funcs, prefix, sizeof(BTF_FUNC) - 1); + /* set8 */ + } else if (!strncmp(prefix, BTF_SET8, sizeof(BTF_SET8) - 1)) { + id = add_set(obj, prefix, true); + /* + * SET8 objects store list's count, which is encoded + * in symbol's size, together with 'cnt' field hence + * that - 1. + */ + if (id) { + id->cnt = sym.st_size / sizeof(uint64_t) - 1; + id->is_set8 = true; + } + /* set */ + } else if (!strncmp(prefix, BTF_SET, sizeof(BTF_SET) - 1)) { + id = add_set(obj, prefix, false); + /* + * SET objects store list's count, which is encoded + * in symbol's size, together with 'cnt' field hence + * that - 1. + */ + if (id) { + id->cnt = sym.st_size / sizeof(int) - 1; + id->is_set = true; + } + } else { + pr_err("FAILED unsupported prefix %s\n", prefix); + return -1; + } + + if (!id) + return -ENOMEM; + + if (id->addr_cnt >= ADDR_CNT) { + pr_err("FAILED symbol %s crossed the number of allowed lists\n", + id->name); + return -1; + } + id->addr[id->addr_cnt++] = sym.st_value; + } + + return 0; +} + +static int symbols_resolve(struct object *obj) +{ + int nr_typedefs = obj->nr_typedefs; + int nr_structs = obj->nr_structs; + int nr_unions = obj->nr_unions; + int nr_funcs = obj->nr_funcs; + struct btf *base_btf = NULL; + int err, type_id; + struct btf *btf; + __u32 nr_types; + + if (obj->base_btf_path) { + base_btf = btf__parse(obj->base_btf_path, NULL); + err = libbpf_get_error(base_btf); + if (err) { + pr_err("FAILED: load base BTF from %s: %s\n", + obj->base_btf_path, strerror(-err)); + return -1; + } + } + + btf = btf__parse_split(obj->btf ?: obj->path, base_btf); + err = libbpf_get_error(btf); + if (err) { + pr_err("FAILED: load BTF from %s: %s\n", + obj->btf ?: obj->path, strerror(-err)); + goto out; + } + + err = -1; + nr_types = btf__type_cnt(btf); + + /* + * Iterate all the BTF types and search for collected symbol IDs. + */ + for (type_id = 1; type_id < nr_types; type_id++) { + const struct btf_type *type; + struct rb_root *root; + struct btf_id *id; + const char *str; + int *nr; + + type = btf__type_by_id(btf, type_id); + if (!type) { + pr_err("FAILED: malformed BTF, can't resolve type for ID %d\n", + type_id); + goto out; + } + + if (btf_is_func(type) && nr_funcs) { + nr = &nr_funcs; + root = &obj->funcs; + } else if (btf_is_struct(type) && nr_structs) { + nr = &nr_structs; + root = &obj->structs; + } else if (btf_is_union(type) && nr_unions) { + nr = &nr_unions; + root = &obj->unions; + } else if (btf_is_typedef(type) && nr_typedefs) { + nr = &nr_typedefs; + root = &obj->typedefs; + } else + continue; + + str = btf__name_by_offset(btf, type->name_off); + if (!str) { + pr_err("FAILED: malformed BTF, can't resolve name for ID %d\n", + type_id); + goto out; + } + + id = btf_id__find(root, str); + if (id) { + if (id->id) { + pr_info("WARN: multiple IDs found for '%s': %d, %d - using %d\n", + str, id->id, type_id, id->id); + } else { + id->id = type_id; + (*nr)--; + } + } + } + + err = 0; +out: + btf__free(base_btf); + btf__free(btf); + return err; +} + +static int id_patch(struct object *obj, struct btf_id *id) +{ + Elf_Data *data = obj->efile.idlist; + int *ptr = data->d_buf; + int i; + + /* For set, set8, id->id may be 0 */ + if (!id->id && !id->is_set && !id->is_set8) + pr_err("WARN: resolve_btfids: unresolved symbol %s\n", id->name); + + for (i = 0; i < id->addr_cnt; i++) { + unsigned long addr = id->addr[i]; + unsigned long idx = addr - obj->efile.idlist_addr; + + pr_debug("patching addr %5lu: ID %7d [%s]\n", + idx, id->id, id->name); + + if (idx >= data->d_size) { + pr_err("FAILED patching index %lu out of bounds %lu\n", + idx, data->d_size); + return -1; + } + + idx = idx / sizeof(int); + ptr[idx] = id->id; + } + + return 0; +} + +static int __symbols_patch(struct object *obj, struct rb_root *root) +{ + struct rb_node *next; + struct btf_id *id; + + next = rb_first(root); + while (next) { + id = rb_entry(next, struct btf_id, rb_node); + + if (id_patch(obj, id)) + return -1; + + next = rb_next(next); + } + return 0; +} + +static int cmp_id(const void *pa, const void *pb) +{ + const int *a = pa, *b = pb; + + return *a - *b; +} + +static int sets_patch(struct object *obj) +{ + Elf_Data *data = obj->efile.idlist; + int *ptr = data->d_buf; + struct rb_node *next; + + next = rb_first(&obj->sets); + while (next) { + unsigned long addr, idx; + struct btf_id *id; + int *base; + int cnt; + + id = rb_entry(next, struct btf_id, rb_node); + addr = id->addr[0]; + idx = addr - obj->efile.idlist_addr; + + /* sets are unique */ + if (id->addr_cnt != 1) { + pr_err("FAILED malformed data for set '%s'\n", + id->name); + return -1; + } + + idx = idx / sizeof(int); + base = &ptr[idx] + (id->is_set8 ? 2 : 1); + cnt = ptr[idx]; + + pr_debug("sorting addr %5lu: cnt %6d [%s]\n", + (idx + 1) * sizeof(int), cnt, id->name); + + qsort(base, cnt, id->is_set8 ? sizeof(uint64_t) : sizeof(int), cmp_id); + + next = rb_next(next); + } + return 0; +} + +static int symbols_patch(struct object *obj) +{ + int err; + + if (__symbols_patch(obj, &obj->structs) || + __symbols_patch(obj, &obj->unions) || + __symbols_patch(obj, &obj->typedefs) || + __symbols_patch(obj, &obj->funcs) || + __symbols_patch(obj, &obj->sets)) + return -1; + + if (sets_patch(obj)) + return -1; + + /* Set type to ensure endian translation occurs. */ + obj->efile.idlist->d_type = ELF_T_WORD; + + elf_flagdata(obj->efile.idlist, ELF_C_SET, ELF_F_DIRTY); + + err = elf_update(obj->efile.elf, ELF_C_WRITE); + if (err < 0) { + pr_err("FAILED elf_update(WRITE): %s\n", + elf_errmsg(-1)); + } + + pr_debug("update %s for %s\n", + err >= 0 ? "ok" : "failed", obj->path); + return err < 0 ? -1 : 0; +} + +static const char * const resolve_btfids_usage[] = { + "resolve_btfids [<options>] <ELF object>", + NULL +}; + +int main(int argc, const char **argv) +{ + struct object obj = { + .efile = { + .idlist_shndx = -1, + .symbols_shndx = -1, + }, + .structs = RB_ROOT, + .unions = RB_ROOT, + .typedefs = RB_ROOT, + .funcs = RB_ROOT, + .sets = RB_ROOT, + }; + struct option btfid_options[] = { + OPT_INCR('v', "verbose", &verbose, + "be more verbose (show errors, etc)"), + OPT_STRING(0, "btf", &obj.btf, "BTF data", + "BTF data"), + OPT_STRING('b', "btf_base", &obj.base_btf_path, "file", + "path of file providing base BTF"), + OPT_END() + }; + int err = -1; + + argc = parse_options(argc, argv, btfid_options, resolve_btfids_usage, + PARSE_OPT_STOP_AT_NON_OPTION); + if (argc != 1) + usage_with_options(resolve_btfids_usage, btfid_options); + + obj.path = argv[0]; + + if (elf_collect(&obj)) + goto out; + + /* + * We did not find .BTF_ids section or symbols section, + * nothing to do.. + */ + if (obj.efile.idlist_shndx == -1 || + obj.efile.symbols_shndx == -1) { + pr_debug("Cannot find .BTF_ids or symbols sections, nothing to do\n"); + err = 0; + goto out; + } + + if (symbols_collect(&obj)) + goto out; + + if (symbols_resolve(&obj)) + goto out; + + if (symbols_patch(&obj)) + goto out; + + err = 0; +out: + if (obj.efile.elf) { + elf_end(obj.efile.elf); + close(obj.efile.fd); + } + return err; +} |