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1// SPDX-License-Identifier: GPL-2.02#include <inttypes.h>3#include <limits.h>4#include <stdio.h>5#include <stdlib.h>6#include <string.h>7#include <linux/string.h>8#include <linux/zalloc.h>9#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */10#include "debug.h"11#include "dso.h"12#include "map.h"13#include "namespaces.h"14#include "srcline.h"15#include "symbol.h"16#include "thread.h"17#include "vdso.h"18 19static inline int is_android_lib(const char *filename)20{21	return strstarts(filename, "/data/app-lib/") ||22	       strstarts(filename, "/system/lib/");23}24 25static inline bool replace_android_lib(const char *filename, char *newfilename)26{27	const char *libname;28	char *app_abi;29	size_t app_abi_length, new_length;30	size_t lib_length = 0;31 32	libname  = strrchr(filename, '/');33	if (libname)34		lib_length = strlen(libname);35 36	app_abi = getenv("APP_ABI");37	if (!app_abi)38		return false;39 40	app_abi_length = strlen(app_abi);41 42	if (strstarts(filename, "/data/app-lib/")) {43		char *apk_path;44 45		if (!app_abi_length)46			return false;47 48		new_length = 7 + app_abi_length + lib_length;49 50		apk_path = getenv("APK_PATH");51		if (apk_path) {52			new_length += strlen(apk_path) + 1;53			if (new_length > PATH_MAX)54				return false;55			snprintf(newfilename, new_length,56				 "%s/libs/%s/%s", apk_path, app_abi, libname);57		} else {58			if (new_length > PATH_MAX)59				return false;60			snprintf(newfilename, new_length,61				 "libs/%s/%s", app_abi, libname);62		}63		return true;64	}65 66	if (strstarts(filename, "/system/lib/")) {67		char *ndk, *app;68		const char *arch;69		int ndk_length, app_length;70 71		ndk = getenv("NDK_ROOT");72		app = getenv("APP_PLATFORM");73 74		if (!(ndk && app))75			return false;76 77		ndk_length = strlen(ndk);78		app_length = strlen(app);79 80		if (!(ndk_length && app_length && app_abi_length))81			return false;82 83		arch = !strncmp(app_abi, "arm", 3) ? "arm" :84		       !strncmp(app_abi, "mips", 4) ? "mips" :85		       !strncmp(app_abi, "x86", 3) ? "x86" : NULL;86 87		if (!arch)88			return false;89 90		new_length = 27 + ndk_length +91			     app_length + lib_length92			   + strlen(arch);93 94		if (new_length > PATH_MAX)95			return false;96		snprintf(newfilename, new_length,97			"%.*s/platforms/%.*s/arch-%s/usr/lib/%s",98			ndk_length, ndk, app_length, app, arch, libname);99 100		return true;101	}102	return false;103}104 105static void map__init(struct map *map, u64 start, u64 end, u64 pgoff,106		      struct dso *dso, u32 prot, u32 flags)107{108	map__set_start(map, start);109	map__set_end(map, end);110	map__set_pgoff(map, pgoff);111	assert(map__reloc(map) == 0);112	map__set_dso(map, dso__get(dso));113	refcount_set(map__refcnt(map), 1);114	RC_CHK_ACCESS(map)->prot = prot;115	RC_CHK_ACCESS(map)->flags = flags;116	map__set_mapping_type(map, MAPPING_TYPE__DSO);117	assert(map__erange_warned(map) == false);118	assert(map__priv(map) == false);119	assert(map__hit(map) == false);120}121 122struct map *map__new(struct machine *machine, u64 start, u64 len,123		     u64 pgoff, struct dso_id *id,124		     u32 prot, u32 flags, struct build_id *bid,125		     char *filename, struct thread *thread)126{127	struct map *result;128	RC_STRUCT(map) *map;129	struct nsinfo *nsi = NULL;130	struct nsinfo *nnsi;131 132	map = zalloc(sizeof(*map));133	if (ADD_RC_CHK(result, map)) {134		char newfilename[PATH_MAX];135		struct dso *dso, *header_bid_dso;136		int anon, no_dso, vdso, android;137 138		android = is_android_lib(filename);139		anon = is_anon_memory(filename) || flags & MAP_HUGETLB;140		vdso = is_vdso_map(filename);141		no_dso = is_no_dso_memory(filename);142		nsi = nsinfo__get(thread__nsinfo(thread));143 144		if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {145			snprintf(newfilename, sizeof(newfilename),146				 "/tmp/perf-%d.map", nsinfo__pid(nsi));147			filename = newfilename;148		}149 150		if (android) {151			if (replace_android_lib(filename, newfilename))152				filename = newfilename;153		}154 155		if (vdso) {156			/* The vdso maps are always on the host and not the157			 * container.  Ensure that we don't use setns to look158			 * them up.159			 */160			nnsi = nsinfo__copy(nsi);161			if (nnsi) {162				nsinfo__put(nsi);163				nsinfo__clear_need_setns(nnsi);164				nsi = nnsi;165			}166			pgoff = 0;167			dso = machine__findnew_vdso(machine, thread);168		} else169			dso = machine__findnew_dso_id(machine, filename, id);170 171		if (dso == NULL)172			goto out_delete;173 174		assert(!dso__kernel(dso));175		map__init(result, start, start + len, pgoff, dso, prot, flags);176 177		if (anon || no_dso) {178			map->mapping_type = MAPPING_TYPE__IDENTITY;179 180			/*181			 * Set memory without DSO as loaded. All map__find_*182			 * functions still return NULL, and we avoid the183			 * unnecessary map__load warning.184			 */185			if (!(prot & PROT_EXEC))186				dso__set_loaded(dso);187		}188		mutex_lock(dso__lock(dso));189		dso__set_nsinfo(dso, nsi);190		mutex_unlock(dso__lock(dso));191 192		if (build_id__is_defined(bid)) {193			dso__set_build_id(dso, bid);194		} else {195			/*196			 * If the mmap event had no build ID, search for an existing dso from the197			 * build ID header by name. Otherwise only the dso loaded at the time of198			 * reading the header will have the build ID set and all future mmaps will199			 * have it missing.200			 */201			header_bid_dso = dsos__find(&machine->dsos, filename, false);202			if (header_bid_dso && dso__header_build_id(header_bid_dso)) {203				dso__set_build_id(dso, dso__bid(header_bid_dso));204				dso__set_header_build_id(dso, 1);205			}206			dso__put(header_bid_dso);207		}208		dso__put(dso);209	}210	return result;211out_delete:212	nsinfo__put(nsi);213	RC_CHK_FREE(result);214	return NULL;215}216 217/*218 * Constructor variant for modules (where we know from /proc/modules where219 * they are loaded) and for vmlinux, where only after we load all the220 * symbols we'll know where it starts and ends.221 */222struct map *map__new2(u64 start, struct dso *dso)223{224	struct map *result;225	RC_STRUCT(map) *map;226 227	map = calloc(1, sizeof(*map) + (dso__kernel(dso) ? sizeof(struct kmap) : 0));228	if (ADD_RC_CHK(result, map)) {229		/* ->end will be filled after we load all the symbols. */230		map__init(result, start, /*end=*/0, /*pgoff=*/0, dso, /*prot=*/0, /*flags=*/0);231	}232 233	return result;234}235 236bool __map__is_kernel(const struct map *map)237{238	if (!dso__kernel(map__dso(map)))239		return false;240	return machine__kernel_map(maps__machine(map__kmaps((struct map *)map))) == map;241}242 243bool __map__is_extra_kernel_map(const struct map *map)244{245	struct kmap *kmap = __map__kmap((struct map *)map);246 247	return kmap && kmap->name[0];248}249 250bool __map__is_bpf_prog(const struct map *map)251{252	const char *name;253	struct dso *dso = map__dso(map);254 255	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_PROG_INFO)256		return true;257 258	/*259	 * If PERF_RECORD_BPF_EVENT is not included, the dso will not have260	 * type of DSO_BINARY_TYPE__BPF_PROG_INFO. In such cases, we can261	 * guess the type based on name.262	 */263	name = dso__short_name(dso);264	return name && (strstr(name, "bpf_prog_") == name);265}266 267bool __map__is_bpf_image(const struct map *map)268{269	const char *name;270	struct dso *dso = map__dso(map);271 272	if (dso__binary_type(dso) == DSO_BINARY_TYPE__BPF_IMAGE)273		return true;274 275	/*276	 * If PERF_RECORD_KSYMBOL is not included, the dso will not have277	 * type of DSO_BINARY_TYPE__BPF_IMAGE. In such cases, we can278	 * guess the type based on name.279	 */280	name = dso__short_name(dso);281	return name && is_bpf_image(name);282}283 284bool __map__is_ool(const struct map *map)285{286	const struct dso *dso = map__dso(map);287 288	return dso && dso__binary_type(dso) == DSO_BINARY_TYPE__OOL;289}290 291bool map__has_symbols(const struct map *map)292{293	return dso__has_symbols(map__dso(map));294}295 296static void map__exit(struct map *map)297{298	BUG_ON(refcount_read(map__refcnt(map)) != 0);299	dso__zput(RC_CHK_ACCESS(map)->dso);300}301 302void map__delete(struct map *map)303{304	map__exit(map);305	RC_CHK_FREE(map);306}307 308void map__put(struct map *map)309{310	if (map && refcount_dec_and_test(map__refcnt(map)))311		map__delete(map);312	else313		RC_CHK_PUT(map);314}315 316void map__fixup_start(struct map *map)317{318	struct dso *dso = map__dso(map);319	struct rb_root_cached *symbols = dso__symbols(dso);320	struct rb_node *nd = rb_first_cached(symbols);321 322	if (nd != NULL) {323		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);324 325		map__set_start(map, sym->start);326	}327}328 329void map__fixup_end(struct map *map)330{331	struct dso *dso = map__dso(map);332	struct rb_root_cached *symbols = dso__symbols(dso);333	struct rb_node *nd = rb_last(&symbols->rb_root);334 335	if (nd != NULL) {336		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);337		map__set_end(map, sym->end);338	}339}340 341#define DSO__DELETED "(deleted)"342 343int map__load(struct map *map)344{345	struct dso *dso = map__dso(map);346	const char *name = dso__long_name(dso);347	int nr;348 349	if (dso__loaded(dso))350		return 0;351 352	nr = dso__load(dso, map);353	if (nr < 0) {354		if (dso__has_build_id(dso)) {355			char sbuild_id[SBUILD_ID_SIZE];356 357			build_id__sprintf(dso__bid(dso), sbuild_id);358			pr_debug("%s with build id %s not found", name, sbuild_id);359		} else360			pr_debug("Failed to open %s", name);361 362		pr_debug(", continuing without symbols\n");363		return -1;364	} else if (nr == 0) {365#ifdef HAVE_LIBELF_SUPPORT366		const size_t len = strlen(name);367		const size_t real_len = len - sizeof(DSO__DELETED);368 369		if (len > sizeof(DSO__DELETED) &&370		    strcmp(name + real_len + 1, DSO__DELETED) == 0) {371			pr_debug("%.*s was updated (is prelink enabled?). "372				"Restart the long running apps that use it!\n",373				   (int)real_len, name);374		} else {375			pr_debug("no symbols found in %s, maybe install a debug package?\n", name);376		}377#endif378		return -1;379	}380 381	return 0;382}383 384struct symbol *map__find_symbol(struct map *map, u64 addr)385{386	if (map__load(map) < 0)387		return NULL;388 389	return dso__find_symbol(map__dso(map), addr);390}391 392struct symbol *map__find_symbol_by_name_idx(struct map *map, const char *name, size_t *idx)393{394	struct dso *dso;395 396	if (map__load(map) < 0)397		return NULL;398 399	dso = map__dso(map);400	dso__sort_by_name(dso);401 402	return dso__find_symbol_by_name(dso, name, idx);403}404 405struct symbol *map__find_symbol_by_name(struct map *map, const char *name)406{407	size_t idx;408 409	return map__find_symbol_by_name_idx(map, name, &idx);410}411 412struct map *map__clone(struct map *from)413{414	struct map *result;415	RC_STRUCT(map) *map;416	size_t size = sizeof(RC_STRUCT(map));417	struct dso *dso = map__dso(from);418 419	if (dso && dso__kernel(dso))420		size += sizeof(struct kmap);421 422	map = memdup(RC_CHK_ACCESS(from), size);423	if (ADD_RC_CHK(result, map)) {424		refcount_set(&map->refcnt, 1);425		map->dso = dso__get(dso);426	}427 428	return result;429}430 431size_t map__fprintf(struct map *map, FILE *fp)432{433	const struct dso *dso = map__dso(map);434 435	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",436		       map__start(map), map__end(map), map__pgoff(map), dso__name(dso));437}438 439static bool prefer_dso_long_name(const struct dso *dso, bool print_off)440{441	return dso__long_name(dso) &&442	       (symbol_conf.show_kernel_path ||443		(print_off && (dso__name(dso)[0] == '[' || dso__is_kcore(dso))));444}445 446static size_t __map__fprintf_dsoname(struct map *map, bool print_off, FILE *fp)447{448	char buf[symbol_conf.pad_output_len_dso + 1];449	const char *dsoname = "[unknown]";450	const struct dso *dso = map ? map__dso(map) : NULL;451 452	if (dso) {453		if (prefer_dso_long_name(dso, print_off))454			dsoname = dso__long_name(dso);455		else456			dsoname = dso__name(dso);457	}458 459	if (symbol_conf.pad_output_len_dso) {460		scnprintf_pad(buf, symbol_conf.pad_output_len_dso, "%s", dsoname);461		dsoname = buf;462	}463 464	return fprintf(fp, "%s", dsoname);465}466 467size_t map__fprintf_dsoname(struct map *map, FILE *fp)468{469	return __map__fprintf_dsoname(map, false, fp);470}471 472size_t map__fprintf_dsoname_dsoff(struct map *map, bool print_off, u64 addr, FILE *fp)473{474	const struct dso *dso = map ? map__dso(map) : NULL;475	int printed = 0;476 477	if (print_off && (!dso || !dso__is_object_file(dso)))478		print_off = false;479	printed += fprintf(fp, " (");480	printed += __map__fprintf_dsoname(map, print_off, fp);481	if (print_off)482		printed += fprintf(fp, "+0x%" PRIx64, addr);483	printed += fprintf(fp, ")");484 485	return printed;486}487 488char *map__srcline(struct map *map, u64 addr, struct symbol *sym)489{490	if (map == NULL)491		return SRCLINE_UNKNOWN;492 493	return get_srcline(map__dso(map), map__rip_2objdump(map, addr), sym, true, true, addr);494}495 496int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,497			 FILE *fp)498{499	const struct dso *dso = map ? map__dso(map) : NULL;500	int ret = 0;501 502	if (dso) {503		char *srcline = map__srcline(map, addr, NULL);504		if (srcline != SRCLINE_UNKNOWN)505			ret = fprintf(fp, "%s%s", prefix, srcline);506		zfree_srcline(&srcline);507	}508	return ret;509}510 511void srccode_state_free(struct srccode_state *state)512{513	zfree(&state->srcfile);514	state->line = 0;515}516 517/**518 * map__rip_2objdump - convert symbol start address to objdump address.519 * @map: memory map520 * @rip: symbol start address521 *522 * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.523 * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is524 * relative to section start.525 *526 * Return: Address suitable for passing to "objdump --start-address="527 */528u64 map__rip_2objdump(struct map *map, u64 rip)529{530	struct kmap *kmap = __map__kmap(map);531	const struct dso *dso = map__dso(map);532 533	/*534	 * vmlinux does not have program headers for PTI entry trampolines and535	 * kcore may not either. However the trampoline object code is on the536	 * main kernel map, so just use that instead.537	 */538	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps) {539		struct machine *machine = maps__machine(kmap->kmaps);540 541		if (machine) {542			struct map *kernel_map = machine__kernel_map(machine);543 544			if (kernel_map)545				map = kernel_map;546		}547	}548 549	if (!dso__adjust_symbols(dso))550		return rip;551 552	if (dso__rel(dso))553		return rip - map__pgoff(map);554 555	if (dso__kernel(dso) == DSO_SPACE__USER)556		return rip + dso__text_offset(dso);557 558	return map__unmap_ip(map, rip) - map__reloc(map);559}560 561/**562 * map__objdump_2mem - convert objdump address to a memory address.563 * @map: memory map564 * @ip: objdump address565 *566 * Closely related to map__rip_2objdump(), this function takes an address from567 * objdump and converts it to a memory address.  Note this assumes that @map568 * contains the address.  To be sure the result is valid, check it forwards569 * e.g. map__rip_2objdump(map__map_ip(map, map__objdump_2mem(map, ip))) == ip570 *571 * Return: Memory address.572 */573u64 map__objdump_2mem(struct map *map, u64 ip)574{575	const struct dso *dso = map__dso(map);576 577	if (!dso__adjust_symbols(dso))578		return map__unmap_ip(map, ip);579 580	if (dso__rel(dso))581		return map__unmap_ip(map, ip + map__pgoff(map));582 583	if (dso__kernel(dso) == DSO_SPACE__USER)584		return map__unmap_ip(map, ip - dso__text_offset(dso));585 586	return ip + map__reloc(map);587}588 589/* convert objdump address to relative address.  (To be removed) */590u64 map__objdump_2rip(struct map *map, u64 ip)591{592	const struct dso *dso = map__dso(map);593 594	if (!dso__adjust_symbols(dso))595		return ip;596 597	if (dso__rel(dso))598		return ip + map__pgoff(map);599 600	if (dso__kernel(dso) == DSO_SPACE__USER)601		return ip - dso__text_offset(dso);602 603	return map__map_ip(map, ip + map__reloc(map));604}605 606bool map__contains_symbol(const struct map *map, const struct symbol *sym)607{608	u64 ip = map__unmap_ip(map, sym->start);609 610	return ip >= map__start(map) && ip < map__end(map);611}612 613struct kmap *__map__kmap(struct map *map)614{615	const struct dso *dso = map__dso(map);616 617	if (!dso || !dso__kernel(dso))618		return NULL;619	return (struct kmap *)(&RC_CHK_ACCESS(map)[1]);620}621 622struct kmap *map__kmap(struct map *map)623{624	struct kmap *kmap = __map__kmap(map);625 626	if (!kmap)627		pr_err("Internal error: map__kmap with a non-kernel map\n");628	return kmap;629}630 631struct maps *map__kmaps(struct map *map)632{633	struct kmap *kmap = map__kmap(map);634 635	if (!kmap || !kmap->kmaps) {636		pr_err("Internal error: map__kmaps with a non-kernel map\n");637		return NULL;638	}639	return kmap->kmaps;640}641