Add a basic CRC32 implementation adapted from genksyms, and produce matching output from symtypes strings in type_map. Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> --- scripts/gendwarfksyms/Makefile | 1 + scripts/gendwarfksyms/crc32.c | 69 ++++++++++++++ scripts/gendwarfksyms/crc32.h | 34 +++++++ scripts/gendwarfksyms/dwarf.c | 47 ++++++++-- scripts/gendwarfksyms/gendwarfksyms.c | 10 ++- scripts/gendwarfksyms/gendwarfksyms.h | 15 +++- scripts/gendwarfksyms/symbols.c | 65 ++++++++++++++ scripts/gendwarfksyms/types.c | 124 +++++++++++++++++++++++++- 8 files changed, 348 insertions(+), 17 deletions(-) create mode 100644 scripts/gendwarfksyms/crc32.c create mode 100644 scripts/gendwarfksyms/crc32.h diff --git a/scripts/gendwarfksyms/Makefile b/scripts/gendwarfksyms/Makefile index 4866a2fd0e46..2043601df736 100644 --- a/scripts/gendwarfksyms/Makefile +++ b/scripts/gendwarfksyms/Makefile @@ -2,6 +2,7 @@ hostprogs-always-y += gendwarfksyms gendwarfksyms-objs += gendwarfksyms.o gendwarfksyms-objs += cache.o +gendwarfksyms-objs += crc32.o gendwarfksyms-objs += die.o gendwarfksyms-objs += dwarf.o gendwarfksyms-objs += symbols.o diff --git a/scripts/gendwarfksyms/crc32.c b/scripts/gendwarfksyms/crc32.c new file mode 100644 index 000000000000..23b328cd74f2 --- /dev/null +++ b/scripts/gendwarfksyms/crc32.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Based on scripts/genksyms/genksyms.c, which has the following + * notice: + * + * Generate kernel symbol version hashes. + * Copyright 1996, 1997 Linux International. + * + * New implementation contributed by Richard Henderson <rth@xxxxxxxx> + * Based on original work by Bjorn Ekwall <bj0rn@xxxxxxx> + * + * This file was part of the Linux modutils 2.4.22: moved back into the + * kernel sources by Rusty Russell/Kai Germaschewski. + */ + +const unsigned int crctab32[] = { + 0x00000000U, 0x77073096U, 0xee0e612cU, 0x990951baU, 0x076dc419U, + 0x706af48fU, 0xe963a535U, 0x9e6495a3U, 0x0edb8832U, 0x79dcb8a4U, + 0xe0d5e91eU, 0x97d2d988U, 0x09b64c2bU, 0x7eb17cbdU, 0xe7b82d07U, + 0x90bf1d91U, 0x1db71064U, 0x6ab020f2U, 0xf3b97148U, 0x84be41deU, + 0x1adad47dU, 0x6ddde4ebU, 0xf4d4b551U, 0x83d385c7U, 0x136c9856U, + 0x646ba8c0U, 0xfd62f97aU, 0x8a65c9ecU, 0x14015c4fU, 0x63066cd9U, + 0xfa0f3d63U, 0x8d080df5U, 0x3b6e20c8U, 0x4c69105eU, 0xd56041e4U, + 0xa2677172U, 0x3c03e4d1U, 0x4b04d447U, 0xd20d85fdU, 0xa50ab56bU, + 0x35b5a8faU, 0x42b2986cU, 0xdbbbc9d6U, 0xacbcf940U, 0x32d86ce3U, + 0x45df5c75U, 0xdcd60dcfU, 0xabd13d59U, 0x26d930acU, 0x51de003aU, + 0xc8d75180U, 0xbfd06116U, 0x21b4f4b5U, 0x56b3c423U, 0xcfba9599U, + 0xb8bda50fU, 0x2802b89eU, 0x5f058808U, 0xc60cd9b2U, 0xb10be924U, + 0x2f6f7c87U, 0x58684c11U, 0xc1611dabU, 0xb6662d3dU, 0x76dc4190U, + 0x01db7106U, 0x98d220bcU, 0xefd5102aU, 0x71b18589U, 0x06b6b51fU, + 0x9fbfe4a5U, 0xe8b8d433U, 0x7807c9a2U, 0x0f00f934U, 0x9609a88eU, + 0xe10e9818U, 0x7f6a0dbbU, 0x086d3d2dU, 0x91646c97U, 0xe6635c01U, + 0x6b6b51f4U, 0x1c6c6162U, 0x856530d8U, 0xf262004eU, 0x6c0695edU, + 0x1b01a57bU, 0x8208f4c1U, 0xf50fc457U, 0x65b0d9c6U, 0x12b7e950U, + 0x8bbeb8eaU, 0xfcb9887cU, 0x62dd1ddfU, 0x15da2d49U, 0x8cd37cf3U, + 0xfbd44c65U, 0x4db26158U, 0x3ab551ceU, 0xa3bc0074U, 0xd4bb30e2U, + 0x4adfa541U, 0x3dd895d7U, 0xa4d1c46dU, 0xd3d6f4fbU, 0x4369e96aU, + 0x346ed9fcU, 0xad678846U, 0xda60b8d0U, 0x44042d73U, 0x33031de5U, + 0xaa0a4c5fU, 0xdd0d7cc9U, 0x5005713cU, 0x270241aaU, 0xbe0b1010U, + 0xc90c2086U, 0x5768b525U, 0x206f85b3U, 0xb966d409U, 0xce61e49fU, + 0x5edef90eU, 0x29d9c998U, 0xb0d09822U, 0xc7d7a8b4U, 0x59b33d17U, + 0x2eb40d81U, 0xb7bd5c3bU, 0xc0ba6cadU, 0xedb88320U, 0x9abfb3b6U, + 0x03b6e20cU, 0x74b1d29aU, 0xead54739U, 0x9dd277afU, 0x04db2615U, + 0x73dc1683U, 0xe3630b12U, 0x94643b84U, 0x0d6d6a3eU, 0x7a6a5aa8U, + 0xe40ecf0bU, 0x9309ff9dU, 0x0a00ae27U, 0x7d079eb1U, 0xf00f9344U, + 0x8708a3d2U, 0x1e01f268U, 0x6906c2feU, 0xf762575dU, 0x806567cbU, + 0x196c3671U, 0x6e6b06e7U, 0xfed41b76U, 0x89d32be0U, 0x10da7a5aU, + 0x67dd4accU, 0xf9b9df6fU, 0x8ebeeff9U, 0x17b7be43U, 0x60b08ed5U, + 0xd6d6a3e8U, 0xa1d1937eU, 0x38d8c2c4U, 0x4fdff252U, 0xd1bb67f1U, + 0xa6bc5767U, 0x3fb506ddU, 0x48b2364bU, 0xd80d2bdaU, 0xaf0a1b4cU, + 0x36034af6U, 0x41047a60U, 0xdf60efc3U, 0xa867df55U, 0x316e8eefU, + 0x4669be79U, 0xcb61b38cU, 0xbc66831aU, 0x256fd2a0U, 0x5268e236U, + 0xcc0c7795U, 0xbb0b4703U, 0x220216b9U, 0x5505262fU, 0xc5ba3bbeU, + 0xb2bd0b28U, 0x2bb45a92U, 0x5cb36a04U, 0xc2d7ffa7U, 0xb5d0cf31U, + 0x2cd99e8bU, 0x5bdeae1dU, 0x9b64c2b0U, 0xec63f226U, 0x756aa39cU, + 0x026d930aU, 0x9c0906a9U, 0xeb0e363fU, 0x72076785U, 0x05005713U, + 0x95bf4a82U, 0xe2b87a14U, 0x7bb12baeU, 0x0cb61b38U, 0x92d28e9bU, + 0xe5d5be0dU, 0x7cdcefb7U, 0x0bdbdf21U, 0x86d3d2d4U, 0xf1d4e242U, + 0x68ddb3f8U, 0x1fda836eU, 0x81be16cdU, 0xf6b9265bU, 0x6fb077e1U, + 0x18b74777U, 0x88085ae6U, 0xff0f6a70U, 0x66063bcaU, 0x11010b5cU, + 0x8f659effU, 0xf862ae69U, 0x616bffd3U, 0x166ccf45U, 0xa00ae278U, + 0xd70dd2eeU, 0x4e048354U, 0x3903b3c2U, 0xa7672661U, 0xd06016f7U, + 0x4969474dU, 0x3e6e77dbU, 0xaed16a4aU, 0xd9d65adcU, 0x40df0b66U, + 0x37d83bf0U, 0xa9bcae53U, 0xdebb9ec5U, 0x47b2cf7fU, 0x30b5ffe9U, + 0xbdbdf21cU, 0xcabac28aU, 0x53b39330U, 0x24b4a3a6U, 0xbad03605U, + 0xcdd70693U, 0x54de5729U, 0x23d967bfU, 0xb3667a2eU, 0xc4614ab8U, + 0x5d681b02U, 0x2a6f2b94U, 0xb40bbe37U, 0xc30c8ea1U, 0x5a05df1bU, + 0x2d02ef8dU +}; diff --git a/scripts/gendwarfksyms/crc32.h b/scripts/gendwarfksyms/crc32.h new file mode 100644 index 000000000000..89e4454b2a70 --- /dev/null +++ b/scripts/gendwarfksyms/crc32.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Based on scripts/genksyms/genksyms.c, which has the following + * notice: + * + * Generate kernel symbol version hashes. + * Copyright 1996, 1997 Linux International. + * + * New implementation contributed by Richard Henderson <rth@xxxxxxxx> + * Based on original work by Bjorn Ekwall <bj0rn@xxxxxxx> + * + * This file was part of the Linux modutils 2.4.22: moved back into the + * kernel sources by Rusty Russell/Kai Germaschewski. + */ + +#ifndef __CRC32_H +#define __CRC32_H + +extern const unsigned int crctab32[]; + +static inline unsigned long partial_crc32_one(unsigned char c, + unsigned long crc) +{ + return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8); +} + +static inline unsigned long partial_crc32(const char *s, unsigned long crc) +{ + while (*s) + crc = partial_crc32_one(*s++, crc); + return crc; +} + +#endif /* __CRC32_H */ diff --git a/scripts/gendwarfksyms/dwarf.c b/scripts/gendwarfksyms/dwarf.c index 62241cc97a76..677190ae18ef 100644 --- a/scripts/gendwarfksyms/dwarf.c +++ b/scripts/gendwarfksyms/dwarf.c @@ -693,18 +693,51 @@ static int process_type(struct state *state, struct die *parent, Dwarf_Die *die) /* * Exported symbol processing */ +static int get_symbol_cache(struct state *state, Dwarf_Die *die, + struct die **cache) +{ + checkp(symbol_set_die(state->sym, die)); + check(die_map_get(die, SYMBOL, cache)); + + if ((*cache)->state != INCOMPLETE) + return 1; /* We already processed a symbol for this DIE */ + + (*cache)->tag = dwarf_tag(die); + return 0; +} + static int process_subprogram(struct state *state, Dwarf_Die *die) { - check(__process_subroutine_type(state, NULL, die, "subprogram")); - state->sym->state = MAPPED; + struct die *cache; + + if (checkp(get_symbol_cache(state, die, &cache)) > 0) + return 0; + + debug("%s", state->sym->name); + check(__process_subroutine_type(state, cache, die, "subprogram")); + cache->state = SYMBOL; + + if (dump_dies) + fputs("\n", stderr); + return 0; } static int process_variable(struct state *state, Dwarf_Die *die) { - check(process(state, NULL, "variable ")); - check(process_type_attr(state, NULL, die)); - state->sym->state = MAPPED; + struct die *cache; + + if (checkp(get_symbol_cache(state, die, &cache)) > 0) + return 0; + + debug("%s", state->sym->name); + check(process(state, cache, "variable ")); + check(process_type_attr(state, cache, die)); + cache->state = SYMBOL; + + if (dump_dies) + fputs("\n", stderr); + return 0; } @@ -750,7 +783,6 @@ static int process_exported_symbols(struct state *state, struct die *cache, if (!is_export_symbol(state, die)) return 0; - debug("%s", state->sym->name); state_init(state); if (is_symbol_ptr(get_name(&state->die))) @@ -760,9 +792,6 @@ static int process_exported_symbols(struct state *state, struct die *cache, else check(process_variable(state, &state->die)); - if (dump_dies) - fputs("\n", stderr); - cache_clear_expanded(&state->expansion_cache); return 0; default: diff --git a/scripts/gendwarfksyms/gendwarfksyms.c b/scripts/gendwarfksyms/gendwarfksyms.c index 6a219a54c342..4a160d19d7df 100644 --- a/scripts/gendwarfksyms/gendwarfksyms.c +++ b/scripts/gendwarfksyms/gendwarfksyms.c @@ -22,6 +22,8 @@ bool dump_dies; bool dump_die_map; /* Print out type_map contents */ bool dump_types; +/* Print out expanded type strings used for version calculations */ +bool dump_versions; /* Produce a symtypes file */ bool symtypes; static const char *symtypes_file; @@ -35,6 +37,7 @@ static const struct { { "--dump-dies", &dump_dies, NULL }, { "--dump-die-map", &dump_die_map, NULL }, { "--dump-types", &dump_types, NULL }, + { "--dump-versions", &dump_versions, NULL }, { "--symtypes", &symtypes, &symtypes_file }, }; @@ -109,9 +112,10 @@ static int process_modules(Dwfl_Module *mod, void **userdata, const char *name, } while (cu); /* - * Use die_map to expand type strings and write them to `symfile`. + * Use die_map to expand type strings, write them to `symfile`, and + * calculate symbol versions. */ - check(generate_symtypes(symfile)); + check(generate_symtypes_and_versions(symfile)); die_map_free(); return DWARF_CB_OK; @@ -187,5 +191,7 @@ int main(int argc, const char **argv) if (symfile) fclose(symfile); + symbol_print_versions(); + return 0; } diff --git a/scripts/gendwarfksyms/gendwarfksyms.h b/scripts/gendwarfksyms/gendwarfksyms.h index 6edbd6478e0f..f85e080a8634 100644 --- a/scripts/gendwarfksyms/gendwarfksyms.h +++ b/scripts/gendwarfksyms/gendwarfksyms.h @@ -23,6 +23,7 @@ extern bool debug; extern bool dump_dies; extern bool dump_die_map; extern bool dump_types; +extern bool dump_versions; extern bool symtypes; #define MAX_INPUT_FILES 128 @@ -95,7 +96,7 @@ extern bool symtypes; #define SYMBOL_DECLONLY_PREFIX "__gendwarfksyms_declonly_" #define SYMBOL_DECLONLY_PREFIX_LEN (sizeof(SYMBOL_DECLONLY_PREFIX) - 1) -enum symbol_state { UNPROCESSED, MAPPED }; +enum symbol_state { UNPROCESSED, MAPPED, PROCESSED }; struct symbol_addr { uint32_t section; @@ -119,18 +120,25 @@ struct symbol { struct hlist_node name_hash; enum symbol_state state; uintptr_t die_addr; + unsigned long crc; }; +typedef int (*symbol_callback_t)(struct symbol *, void *arg); + extern bool is_symbol_ptr(const char *name); extern int symbol_read_exports(FILE *file); extern int symbol_read_symtab(int fd); extern struct symbol *symbol_get_unprocessed(const char *name); +extern int symbol_set_die(struct symbol *sym, Dwarf_Die *die); +extern int symbol_set_crc(struct symbol *sym, unsigned long crc); +extern int symbol_for_each(symbol_callback_t func, void *arg); +extern void symbol_print_versions(void); /* * die.c */ -enum die_state { INCOMPLETE, UNEXPANDED, COMPLETE, LAST = COMPLETE }; +enum die_state { INCOMPLETE, UNEXPANDED, COMPLETE, SYMBOL, LAST = SYMBOL }; enum die_fragment_type { EMPTY, STRING, LINEBREAK, DIE }; struct die_fragment { @@ -154,6 +162,7 @@ static inline const char *die_state_name(enum die_state state) CASE_CONST_TO_STR(INCOMPLETE) CASE_CONST_TO_STR(UNEXPANDED) CASE_CONST_TO_STR(COMPLETE) + CASE_CONST_TO_STR(SYMBOL) } } @@ -239,6 +248,6 @@ extern int process_module(Dwfl_Module *mod, Dwarf *dbg, Dwarf_Die *cudie); * types.c */ -extern int generate_symtypes(FILE *file); +extern int generate_symtypes_and_versions(FILE *file); #endif /* __GENDWARFKSYMS_H */ diff --git a/scripts/gendwarfksyms/symbols.c b/scripts/gendwarfksyms/symbols.c index 8cc04e6295a7..c9889cfa89c4 100644 --- a/scripts/gendwarfksyms/symbols.c +++ b/scripts/gendwarfksyms/symbols.c @@ -84,6 +84,38 @@ static int for_each(const char *name, bool name_only, symbol_callback_t func, return 0; } +static int set_crc(struct symbol *sym, void *data) +{ + unsigned long *crc = data; + + if (sym->state == PROCESSED && sym->crc != *crc) + warn("overriding version for symbol %s (crc %lx vs. %lx)", + sym->name, sym->crc, *crc); + + sym->state = PROCESSED; + sym->crc = *crc; + return 0; +} + +int symbol_set_crc(struct symbol *sym, unsigned long crc) +{ + if (checkp(for_each(sym->name, false, set_crc, &crc)) > 0) + return 0; + return -1; +} + +static int set_die(struct symbol *sym, void *data) +{ + sym->die_addr = (uintptr_t)((Dwarf_Die *)data)->addr; + sym->state = MAPPED; + return 0; +} + +int symbol_set_die(struct symbol *sym, Dwarf_Die *die) +{ + return checkp(for_each(sym->name, false, set_die, die)); +} + static bool is_exported(const char *name) { return checkp(for_each(name, true, NULL, NULL)) > 0; @@ -151,6 +183,19 @@ struct symbol *symbol_get_unprocessed(const char *name) return sym; } +int symbol_for_each(symbol_callback_t func, void *arg) +{ + struct hlist_node *tmp; + struct symbol *sym; + int i; + + hash_for_each_safe(symbol_names, i, tmp, sym, name_hash) { + check(func(sym, arg)); + } + + return 0; +} + typedef int (*elf_symbol_callback_t)(const char *name, GElf_Sym *sym, Elf32_Word xndx, void *arg); @@ -264,3 +309,23 @@ int symbol_read_symtab(int fd) { return elf_for_each_symbol(fd, process_symbol, NULL); } + +void symbol_print_versions(void) +{ + struct hlist_node *tmp; + struct symbol *sym; + int i; + + hash_for_each_safe(symbol_names, i, tmp, sym, name_hash) { + if (sym->state != PROCESSED) + warn("no information for symbol %s", sym->name); + + printf("#SYMVER %s 0x%08lx\n", sym->name, sym->crc); + + free((void *)sym->name); + free(sym); + } + + hash_init(symbol_addrs); + hash_init(symbol_names); +} diff --git a/scripts/gendwarfksyms/types.c b/scripts/gendwarfksyms/types.c index 7b9997d8322d..6411b1279a28 100644 --- a/scripts/gendwarfksyms/types.c +++ b/scripts/gendwarfksyms/types.c @@ -228,6 +228,34 @@ static void type_map_free(void) hash_init(type_map); } +/* + * CRC for a type, with an optional fully expanded type string for + * debugging. + */ +struct version { + struct type_expansion type; + unsigned long crc; +}; + +static int version_init(struct version *version) +{ + version->crc = 0xffffffff; + return check(type_expansion_init(&version->type, dump_versions)); +} + +static void version_free(struct version *version) +{ + type_expansion_free(&version->type); +} + +static int version_add(struct version *version, const char *s) +{ + version->crc = partial_crc32(s, version->crc); + if (dump_versions) + checkp(type_expansion_append(&version->type, s, NULL)); + return 0; +} + /* * Type reference format: <prefix>#<name>, where prefix: * s -> structure @@ -271,7 +299,7 @@ static char *get_type_name(struct die *cache) warn("found incomplete cache entry: %p", cache); return NULL; } - if (!cache->fqn) + if (cache->state == SYMBOL || !cache->fqn) return NULL; prefix = get_type_prefix(cache->tag); @@ -305,6 +333,45 @@ static char *get_type_name(struct die *cache) return name; } +static int __calculate_version(struct version *version, struct type_list *list) +{ + struct type_expansion *e; + + /* Calculate a CRC over an expanded type string */ + while (list) { + if (is_type_prefix(list->str)) { + check(type_map_get(list->str, &e)); + + /* + * It's sufficient to expand each type reference just + * once to detect changes. + */ + if (cache_was_expanded(&expansion_cache, e)) { + check(version_add(version, list->str)); + } else { + check(cache_mark_expanded(&expansion_cache, e)); + check(__calculate_version(version, + e->expanded)); + } + } else { + check(version_add(version, list->str)); + } + + list = list->next; + } + + return 0; +} + +static int calculate_version(struct version *version, const char *name, + struct type_list *list) +{ + check(version_init(version)); + check(__calculate_version(version, list)); + cache_clear_expanded(&expansion_cache); + return 0; +} + static int __type_expand(struct die *cache, struct type_expansion *type, bool recursive); @@ -411,7 +478,51 @@ static int expand_type(struct die *cache, void *arg) return 0; } -int generate_symtypes(FILE *file) +static int expand_symbol(struct symbol *sym, void *arg) +{ + struct type_expansion type; + struct version version; + struct die *cache; + + /* + * No need to expand again unless we want a symtypes file entry + * for the symbol. Note that this means `sym` has the same address + * as another symbol that was already processed. + */ + if (!symtypes && sym->state == PROCESSED) + return 0; + + if (__die_map_get(sym->die_addr, SYMBOL, &cache)) + return 0; /* We'll warn about missing CRCs later. */ + + check(type_expand(cache, &type, false)); + + /* If the symbol already has a version, don't calculate it again. */ + if (sym->state != PROCESSED) { + check(calculate_version(&version, sym->name, type.expanded)); + check(symbol_set_crc(sym, version.crc)); + debug("%s = %lx", sym->name, version.crc); + + if (dump_versions) { + fputs(sym->name, stderr); + fputs(" ", stderr); + type_list_write(version.type.expanded, stderr); + fputs("\n", stderr); + } + + version_free(&version); + } + + /* These aren't needed in type_map unless we want a symtypes file. */ + if (symtypes) + check(type_map_add(sym->name, &type)); + + type_expansion_free(&type); + + return 0; +} + +int generate_symtypes_and_versions(FILE *file) { hash_init(expansion_cache.cache); @@ -429,7 +540,14 @@ int generate_symtypes(FILE *file) check(die_map_for_each(expand_type, NULL)); /* - * 2. If a symtypes file is requested, write type_map contents to + * 2. For each exported symbol, expand the die_cache type, and use + * type_map expansions to calculate a symbol version from the + * fully expanded type string. + */ + check(symbol_for_each(expand_symbol, NULL)); + + /* + * 3. If a symtypes file is requested, write type_map contents to * the file. */ check(type_map_write(file)); -- 2.46.0.184.g6999bdac58-goog