Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 959 insertions, 0 deletions

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
new file mode 100644
index 000000000..f4d44f75b
--- /dev/null
+++ b/tools/perf/util/map.c
@@ -0,0 +1,959 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "symbol.h"
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
+#include "dso.h"
+#include "map.h"
+#include "map_symbol.h"
+#include "thread.h"
+#include "vdso.h"
+#include "build-id.h"
+#include "debug.h"
+#include "machine.h"
+#include <linux/string.h>
+#include <linux/zalloc.h>
+#include "srcline.h"
+#include "namespaces.h"
+#include "unwind.h"
+#include "srccode.h"
+#include "ui/ui.h"
+
+static void __maps__insert(struct maps *maps, struct map *map);
+
+static inline int is_android_lib(const char *filename)
+{
+	return strstarts(filename, "/data/app-lib/") ||
+	       strstarts(filename, "/system/lib/");
+}
+
+static inline bool replace_android_lib(const char *filename, char *newfilename)
+{
+	const char *libname;
+	char *app_abi;
+	size_t app_abi_length, new_length;
+	size_t lib_length = 0;
+
+	libname  = strrchr(filename, '/');
+	if (libname)
+		lib_length = strlen(libname);
+
+	app_abi = getenv("APP_ABI");
+	if (!app_abi)
+		return false;
+
+	app_abi_length = strlen(app_abi);
+
+	if (strstarts(filename, "/data/app-lib/")) {
+		char *apk_path;
+
+		if (!app_abi_length)
+			return false;
+
+		new_length = 7 + app_abi_length + lib_length;
+
+		apk_path = getenv("APK_PATH");
+		if (apk_path) {
+			new_length += strlen(apk_path) + 1;
+			if (new_length > PATH_MAX)
+				return false;
+			snprintf(newfilename, new_length,
+				 "%s/libs/%s/%s", apk_path, app_abi, libname);
+		} else {
+			if (new_length > PATH_MAX)
+				return false;
+			snprintf(newfilename, new_length,
+				 "libs/%s/%s", app_abi, libname);
+		}
+		return true;
+	}
+
+	if (strstarts(filename, "/system/lib/")) {
+		char *ndk, *app;
+		const char *arch;
+		int ndk_length, app_length;
+
+		ndk = getenv("NDK_ROOT");
+		app = getenv("APP_PLATFORM");
+
+		if (!(ndk && app))
+			return false;
+
+		ndk_length = strlen(ndk);
+		app_length = strlen(app);
+
+		if (!(ndk_length && app_length && app_abi_length))
+			return false;
+
+		arch = !strncmp(app_abi, "arm", 3) ? "arm" :
+		       !strncmp(app_abi, "mips", 4) ? "mips" :
+		       !strncmp(app_abi, "x86", 3) ? "x86" : NULL;
+
+		if (!arch)
+			return false;
+
+		new_length = 27 + ndk_length +
+			     app_length + lib_length
+			   + strlen(arch);
+
+		if (new_length > PATH_MAX)
+			return false;
+		snprintf(newfilename, new_length,
+			"%.*s/platforms/%.*s/arch-%s/usr/lib/%s",
+			ndk_length, ndk, app_length, app, arch, libname);
+
+		return true;
+	}
+	return false;
+}
+
+void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso)
+{
+	map->start    = start;
+	map->end      = end;
+	map->pgoff    = pgoff;
+	map->reloc    = 0;
+	map->dso      = dso__get(dso);
+	map->map_ip   = map__map_ip;
+	map->unmap_ip = map__unmap_ip;
+	RB_CLEAR_NODE(&map->rb_node);
+	map->erange_warned = false;
+	refcount_set(&map->refcnt, 1);
+}
+
+struct map *map__new(struct machine *machine, u64 start, u64 len,
+		     u64 pgoff, struct dso_id *id,
+		     u32 prot, u32 flags, char *filename,
+		     struct thread *thread)
+{
+	struct map *map = malloc(sizeof(*map));
+	struct nsinfo *nsi = NULL;
+	struct nsinfo *nnsi;
+
+	if (map != NULL) {
+		char newfilename[PATH_MAX];
+		struct dso *dso;
+		int anon, no_dso, vdso, android;
+
+		android = is_android_lib(filename);
+		anon = is_anon_memory(filename) || flags & MAP_HUGETLB;
+		vdso = is_vdso_map(filename);
+		no_dso = is_no_dso_memory(filename);
+		map->prot = prot;
+		map->flags = flags;
+		nsi = nsinfo__get(thread->nsinfo);
+
+		if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {
+			snprintf(newfilename, sizeof(newfilename),
+				 "/tmp/perf-%d.map", nsi->pid);
+			filename = newfilename;
+		}
+
+		if (android) {
+			if (replace_android_lib(filename, newfilename))
+				filename = newfilename;
+		}
+
+		if (vdso) {
+			/* The vdso maps are always on the host and not the
+			 * container.  Ensure that we don't use setns to look
+			 * them up.
+			 */
+			nnsi = nsinfo__copy(nsi);
+			if (nnsi) {
+				nsinfo__put(nsi);
+				nnsi->need_setns = false;
+				nsi = nnsi;
+			}
+			pgoff = 0;
+			dso = machine__findnew_vdso(machine, thread);
+		} else
+			dso = machine__findnew_dso_id(machine, filename, id);
+
+		if (dso == NULL)
+			goto out_delete;
+
+		map__init(map, start, start + len, pgoff, dso);
+
+		if (anon || no_dso) {
+			map->map_ip = map->unmap_ip = identity__map_ip;
+
+			/*
+			 * Set memory without DSO as loaded. All map__find_*
+			 * functions still return NULL, and we avoid the
+			 * unnecessary map__load warning.
+			 */
+			if (!(prot & PROT_EXEC))
+				dso__set_loaded(dso);
+		}
+		dso->nsinfo = nsi;
+		dso__put(dso);
+	}
+	return map;
+out_delete:
+	nsinfo__put(nsi);
+	free(map);
+	return NULL;
+}
+
+/*
+ * Constructor variant for modules (where we know from /proc/modules where
+ * they are loaded) and for vmlinux, where only after we load all the
+ * symbols we'll know where it starts and ends.
+ */
+struct map *map__new2(u64 start, struct dso *dso)
+{
+	struct map *map = calloc(1, (sizeof(*map) +
+				     (dso->kernel ? sizeof(struct kmap) : 0)));
+	if (map != NULL) {
+		/*
+		 * ->end will be filled after we load all the symbols
+		 */
+		map__init(map, start, 0, 0, dso);
+	}
+
+	return map;
+}
+
+bool __map__is_kernel(const struct map *map)
+{
+	if (!map->dso->kernel)
+		return false;
+	return machine__kernel_map(map__kmaps((struct map *)map)->machine) == map;
+}
+
+bool __map__is_extra_kernel_map(const struct map *map)
+{
+	struct kmap *kmap = __map__kmap((struct map *)map);
+
+	return kmap && kmap->name[0];
+}
+
+bool __map__is_bpf_prog(const struct map *map)
+{
+	const char *name;
+
+	if (map->dso->binary_type == DSO_BINARY_TYPE__BPF_PROG_INFO)
+		return true;
+
+	/*
+	 * If PERF_RECORD_BPF_EVENT is not included, the dso will not have
+	 * type of DSO_BINARY_TYPE__BPF_PROG_INFO. In such cases, we can
+	 * guess the type based on name.
+	 */
+	name = map->dso->short_name;
+	return name && (strstr(name, "bpf_prog_") == name);
+}
+
+bool __map__is_bpf_image(const struct map *map)
+{
+	const char *name;
+
+	if (map->dso->binary_type == DSO_BINARY_TYPE__BPF_IMAGE)
+		return true;
+
+	/*
+	 * If PERF_RECORD_KSYMBOL is not included, the dso will not have
+	 * type of DSO_BINARY_TYPE__BPF_IMAGE. In such cases, we can
+	 * guess the type based on name.
+	 */
+	name = map->dso->short_name;
+	return name && is_bpf_image(name);
+}
+
+bool __map__is_ool(const struct map *map)
+{
+	return map->dso && map->dso->binary_type == DSO_BINARY_TYPE__OOL;
+}
+
+bool map__has_symbols(const struct map *map)
+{
+	return dso__has_symbols(map->dso);
+}
+
+static void map__exit(struct map *map)
+{
+	BUG_ON(refcount_read(&map->refcnt) != 0);
+	dso__zput(map->dso);
+}
+
+void map__delete(struct map *map)
+{
+	map__exit(map);
+	free(map);
+}
+
+void map__put(struct map *map)
+{
+	if (map && refcount_dec_and_test(&map->refcnt))
+		map__delete(map);
+}
+
+void map__fixup_start(struct map *map)
+{
+	struct rb_root_cached *symbols = &map->dso->symbols;
+	struct rb_node *nd = rb_first_cached(symbols);
+	if (nd != NULL) {
+		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
+		map->start = sym->start;
+	}
+}
+
+void map__fixup_end(struct map *map)
+{
+	struct rb_root_cached *symbols = &map->dso->symbols;
+	struct rb_node *nd = rb_last(&symbols->rb_root);
+	if (nd != NULL) {
+		struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
+		map->end = sym->end;
+	}
+}
+
+#define DSO__DELETED "(deleted)"
+
+int map__load(struct map *map)
+{
+	const char *name = map->dso->long_name;
+	int nr;
+
+	if (dso__loaded(map->dso))
+		return 0;
+
+	nr = dso__load(map->dso, map);
+	if (nr < 0) {
+		if (map->dso->has_build_id) {
+			char sbuild_id[SBUILD_ID_SIZE];
+
+			build_id__sprintf(&map->dso->bid, sbuild_id);
+			pr_debug("%s with build id %s not found", name, sbuild_id);
+		} else
+			pr_debug("Failed to open %s", name);
+
+		pr_debug(", continuing without symbols\n");
+		return -1;
+	} else if (nr == 0) {
+#ifdef HAVE_LIBELF_SUPPORT
+		const size_t len = strlen(name);
+		const size_t real_len = len - sizeof(DSO__DELETED);
+
+		if (len > sizeof(DSO__DELETED) &&
+		    strcmp(name + real_len + 1, DSO__DELETED) == 0) {
+			pr_debug("%.*s was updated (is prelink enabled?). "
+				"Restart the long running apps that use it!\n",
+				   (int)real_len, name);
+		} else {
+			pr_debug("no symbols found in %s, maybe install a debug package?\n", name);
+		}
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+struct symbol *map__find_symbol(struct map *map, u64 addr)
+{
+	if (map__load(map) < 0)
+		return NULL;
+
+	return dso__find_symbol(map->dso, addr);
+}
+
+struct symbol *map__find_symbol_by_name(struct map *map, const char *name)
+{
+	if (map__load(map) < 0)
+		return NULL;
+
+	if (!dso__sorted_by_name(map->dso))
+		dso__sort_by_name(map->dso);
+
+	return dso__find_symbol_by_name(map->dso, name);
+}
+
+struct map *map__clone(struct map *from)
+{
+	size_t size = sizeof(struct map);
+	struct map *map;
+
+	if (from->dso && from->dso->kernel)
+		size += sizeof(struct kmap);
+
+	map = memdup(from, size);
+	if (map != NULL) {
+		refcount_set(&map->refcnt, 1);
+		RB_CLEAR_NODE(&map->rb_node);
+		dso__get(map->dso);
+	}
+
+	return map;
+}
+
+size_t map__fprintf(struct map *map, FILE *fp)
+{
+	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
+		       map->start, map->end, map->pgoff, map->dso->name);
+}
+
+size_t map__fprintf_dsoname(struct map *map, FILE *fp)
+{
+	char buf[symbol_conf.pad_output_len_dso + 1];
+	const char *dsoname = "[unknown]";
+
+	if (map && map->dso) {
+		if (symbol_conf.show_kernel_path && map->dso->long_name)
+			dsoname = map->dso->long_name;
+		else
+			dsoname = map->dso->name;
+	}
+
+	if (symbol_conf.pad_output_len_dso) {
+		scnprintf_pad(buf, symbol_conf.pad_output_len_dso, "%s", dsoname);
+		dsoname = buf;
+	}
+
+	return fprintf(fp, "%s", dsoname);
+}
+
+char *map__srcline(struct map *map, u64 addr, struct symbol *sym)
+{
+	if (map == NULL)
+		return SRCLINE_UNKNOWN;
+	return get_srcline(map->dso, map__rip_2objdump(map, addr), sym, true, true, addr);
+}
+
+int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
+			 FILE *fp)
+{
+	int ret = 0;
+
+	if (map && map->dso) {
+		char *srcline = map__srcline(map, addr, NULL);
+		if (strncmp(srcline, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0)
+			ret = fprintf(fp, "%s%s", prefix, srcline);
+		free_srcline(srcline);
+	}
+	return ret;
+}
+
+void srccode_state_free(struct srccode_state *state)
+{
+	zfree(&state->srcfile);
+	state->line = 0;
+}
+
+/**
+ * map__rip_2objdump - convert symbol start address to objdump address.
+ * @map: memory map
+ * @rip: symbol start address
+ *
+ * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
+ * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
+ * relative to section start.
+ *
+ * Return: Address suitable for passing to "objdump --start-address="
+ */
+u64 map__rip_2objdump(struct map *map, u64 rip)
+{
+	struct kmap *kmap = __map__kmap(map);
+
+	/*
+	 * vmlinux does not have program headers for PTI entry trampolines and
+	 * kcore may not either. However the trampoline object code is on the
+	 * main kernel map, so just use that instead.
+	 */
+	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps && kmap->kmaps->machine) {
+		struct map *kernel_map = machine__kernel_map(kmap->kmaps->machine);
+
+		if (kernel_map)
+			map = kernel_map;
+	}
+
+	if (!map->dso->adjust_symbols)
+		return rip;
+
+	if (map->dso->rel)
+		return rip - map->pgoff;
+
+	/*
+	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
+	 * but all kernel modules are ET_REL, so won't get here.
+	 */
+	if (map->dso->kernel == DSO_SPACE__USER)
+		return rip + map->dso->text_offset;
+
+	return map->unmap_ip(map, rip) - map->reloc;
+}
+
+/**
+ * map__objdump_2mem - convert objdump address to a memory address.
+ * @map: memory map
+ * @ip: objdump address
+ *
+ * Closely related to map__rip_2objdump(), this function takes an address from
+ * objdump and converts it to a memory address.  Note this assumes that @map
+ * contains the address.  To be sure the result is valid, check it forwards
+ * e.g. map__rip_2objdump(map->map_ip(map, map__objdump_2mem(map, ip))) == ip
+ *
+ * Return: Memory address.
+ */
+u64 map__objdump_2mem(struct map *map, u64 ip)
+{
+	if (!map->dso->adjust_symbols)
+		return map->unmap_ip(map, ip);
+
+	if (map->dso->rel)
+		return map->unmap_ip(map, ip + map->pgoff);
+
+	/*
+	 * kernel modules also have DSO_TYPE_USER in dso->kernel,
+	 * but all kernel modules are ET_REL, so won't get here.
+	 */
+	if (map->dso->kernel == DSO_SPACE__USER)
+		return map->unmap_ip(map, ip - map->dso->text_offset);
+
+	return ip + map->reloc;
+}
+
+void maps__init(struct maps *maps, struct machine *machine)
+{
+	maps->entries = RB_ROOT;
+	init_rwsem(&maps->lock);
+	maps->machine = machine;
+	maps->last_search_by_name = NULL;
+	maps->nr_maps = 0;
+	maps->maps_by_name = NULL;
+	refcount_set(&maps->refcnt, 1);
+}
+
+static void __maps__free_maps_by_name(struct maps *maps)
+{
+	/*
+	 * Free everything to try to do it from the rbtree in the next search
+	 */
+	zfree(&maps->maps_by_name);
+	maps->nr_maps_allocated = 0;
+}
+
+void maps__insert(struct maps *maps, struct map *map)
+{
+	down_write(&maps->lock);
+	__maps__insert(maps, map);
+	++maps->nr_maps;
+
+	if (map->dso && map->dso->kernel) {
+		struct kmap *kmap = map__kmap(map);
+
+		if (kmap)
+			kmap->kmaps = maps;
+		else
+			pr_err("Internal error: kernel dso with non kernel map\n");
+	}
+
+
+	/*
+	 * If we already performed some search by name, then we need to add the just
+	 * inserted map and resort.
+	 */
+	if (maps->maps_by_name) {
+		if (maps->nr_maps > maps->nr_maps_allocated) {
+			int nr_allocate = maps->nr_maps * 2;
+			struct map **maps_by_name = realloc(maps->maps_by_name, nr_allocate * sizeof(map));
+
+			if (maps_by_name == NULL) {
+				__maps__free_maps_by_name(maps);
+				up_write(&maps->lock);
+				return;
+			}
+
+			maps->maps_by_name = maps_by_name;
+			maps->nr_maps_allocated = nr_allocate;
+		}
+		maps->maps_by_name[maps->nr_maps - 1] = map;
+		__maps__sort_by_name(maps);
+	}
+	up_write(&maps->lock);
+}
+
+static void __maps__remove(struct maps *maps, struct map *map)
+{
+	rb_erase_init(&map->rb_node, &maps->entries);
+	map__put(map);
+}
+
+void maps__remove(struct maps *maps, struct map *map)
+{
+	down_write(&maps->lock);
+	if (maps->last_search_by_name == map)
+		maps->last_search_by_name = NULL;
+
+	__maps__remove(maps, map);
+	--maps->nr_maps;
+	if (maps->maps_by_name)
+		__maps__free_maps_by_name(maps);
+	up_write(&maps->lock);
+}
+
+static void __maps__purge(struct maps *maps)
+{
+	struct map *pos, *next;
+
+	maps__for_each_entry_safe(maps, pos, next) {
+		rb_erase_init(&pos->rb_node,  &maps->entries);
+		map__put(pos);
+	}
+}
+
+void maps__exit(struct maps *maps)
+{
+	down_write(&maps->lock);
+	__maps__purge(maps);
+	up_write(&maps->lock);
+}
+
+bool maps__empty(struct maps *maps)
+{
+	return !maps__first(maps);
+}
+
+struct maps *maps__new(struct machine *machine)
+{
+	struct maps *maps = zalloc(sizeof(*maps));
+
+	if (maps != NULL)
+		maps__init(maps, machine);
+
+	return maps;
+}
+
+void maps__delete(struct maps *maps)
+{
+	maps__exit(maps);
+	unwind__finish_access(maps);
+	free(maps);
+}
+
+void maps__put(struct maps *maps)
+{
+	if (maps && refcount_dec_and_test(&maps->refcnt))
+		maps__delete(maps);
+}
+
+struct symbol *maps__find_symbol(struct maps *maps, u64 addr, struct map **mapp)
+{
+	struct map *map = maps__find(maps, addr);
+
+	/* Ensure map is loaded before using map->map_ip */
+	if (map != NULL && map__load(map) >= 0) {
+		if (mapp != NULL)
+			*mapp = map;
+		return map__find_symbol(map, map->map_ip(map, addr));
+	}
+
+	return NULL;
+}
+
+static bool map__contains_symbol(struct map *map, struct symbol *sym)
+{
+	u64 ip = map->unmap_ip(map, sym->start);
+
+	return ip >= map->start && ip < map->end;
+}
+
+struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name, struct map **mapp)
+{
+	struct symbol *sym;
+	struct map *pos;
+
+	down_read(&maps->lock);
+
+	maps__for_each_entry(maps, pos) {
+		sym = map__find_symbol_by_name(pos, name);
+
+		if (sym == NULL)
+			continue;
+		if (!map__contains_symbol(pos, sym)) {
+			sym = NULL;
+			continue;
+		}
+		if (mapp != NULL)
+			*mapp = pos;
+		goto out;
+	}
+
+	sym = NULL;
+out:
+	up_read(&maps->lock);
+	return sym;
+}
+
+int maps__find_ams(struct maps *maps, struct addr_map_symbol *ams)
+{
+	if (ams->addr < ams->ms.map->start || ams->addr >= ams->ms.map->end) {
+		if (maps == NULL)
+			return -1;
+		ams->ms.map = maps__find(maps, ams->addr);
+		if (ams->ms.map == NULL)
+			return -1;
+	}
+
+	ams->al_addr = ams->ms.map->map_ip(ams->ms.map, ams->addr);
+	ams->ms.sym = map__find_symbol(ams->ms.map, ams->al_addr);
+
+	return ams->ms.sym ? 0 : -1;
+}
+
+size_t maps__fprintf(struct maps *maps, FILE *fp)
+{
+	size_t printed = 0;
+	struct map *pos;
+
+	down_read(&maps->lock);
+
+	maps__for_each_entry(maps, pos) {
+		printed += fprintf(fp, "Map:");
+		printed += map__fprintf(pos, fp);
+		if (verbose > 2) {
+			printed += dso__fprintf(pos->dso, fp);
+			printed += fprintf(fp, "--\n");
+		}
+	}
+
+	up_read(&maps->lock);
+
+	return printed;
+}
+
+int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
+{
+	struct rb_root *root;
+	struct rb_node *next, *first;
+	int err = 0;
+
+	down_write(&maps->lock);
+
+	root = &maps->entries;
+
+	/*
+	 * Find first map where end > map->start.
+	 * Same as find_vma() in kernel.
+	 */
+	next = root->rb_node;
+	first = NULL;
+	while (next) {
+		struct map *pos = rb_entry(next, struct map, rb_node);
+
+		if (pos->end > map->start) {
+			first = next;
+			if (pos->start <= map->start)
+				break;
+			next = next->rb_left;
+		} else
+			next = next->rb_right;
+	}
+
+	next = first;
+	while (next) {
+		struct map *pos = rb_entry(next, struct map, rb_node);
+		next = rb_next(&pos->rb_node);
+
+		/*
+		 * Stop if current map starts after map->end.
+		 * Maps are ordered by start: next will not overlap for sure.
+		 */
+		if (pos->start >= map->end)
+			break;
+
+		if (verbose >= 2) {
+
+			if (use_browser) {
+				pr_debug("overlapping maps in %s (disable tui for more info)\n",
+					   map->dso->name);
+			} else {
+				fputs("overlapping maps:\n", fp);
+				map__fprintf(map, fp);
+				map__fprintf(pos, fp);
+			}
+		}
+
+		rb_erase_init(&pos->rb_node, root);
+		/*
+		 * Now check if we need to create new maps for areas not
+		 * overlapped by the new map:
+		 */
+		if (map->start > pos->start) {
+			struct map *before = map__clone(pos);
+
+			if (before == NULL) {
+				err = -ENOMEM;
+				goto put_map;
+			}
+
+			before->end = map->start;
+			__maps__insert(maps, before);
+			if (verbose >= 2 && !use_browser)
+				map__fprintf(before, fp);
+			map__put(before);
+		}
+
+		if (map->end < pos->end) {
+			struct map *after = map__clone(pos);
+
+			if (after == NULL) {
+				err = -ENOMEM;
+				goto put_map;
+			}
+
+			after->start = map->end;
+			after->pgoff += map->end - pos->start;
+			assert(pos->map_ip(pos, map->end) == after->map_ip(after, map->end));
+			__maps__insert(maps, after);
+			if (verbose >= 2 && !use_browser)
+				map__fprintf(after, fp);
+			map__put(after);
+		}
+put_map:
+		map__put(pos);
+
+		if (err)
+			goto out;
+	}
+
+	err = 0;
+out:
+	up_write(&maps->lock);
+	return err;
+}
+
+/*
+ * XXX This should not really _copy_ te maps, but refcount them.
+ */
+int maps__clone(struct thread *thread, struct maps *parent)
+{
+	struct maps *maps = thread->maps;
+	int err;
+	struct map *map;
+
+	down_read(&parent->lock);
+
+	maps__for_each_entry(parent, map) {
+		struct map *new = map__clone(map);
+
+		if (new == NULL) {
+			err = -ENOMEM;
+			goto out_unlock;
+		}
+
+		err = unwind__prepare_access(maps, new, NULL);
+		if (err)
+			goto out_unlock;
+
+		maps__insert(maps, new);
+		map__put(new);
+	}
+
+	err = 0;
+out_unlock:
+	up_read(&parent->lock);
+	return err;
+}
+
+static void __maps__insert(struct maps *maps, struct map *map)
+{
+	struct rb_node **p = &maps->entries.rb_node;
+	struct rb_node *parent = NULL;
+	const u64 ip = map->start;
+	struct map *m;
+
+	while (*p != NULL) {
+		parent = *p;
+		m = rb_entry(parent, struct map, rb_node);
+		if (ip < m->start)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	rb_link_node(&map->rb_node, parent, p);
+	rb_insert_color(&map->rb_node, &maps->entries);
+	map__get(map);
+}
+
+struct map *maps__find(struct maps *maps, u64 ip)
+{
+	struct rb_node *p;
+	struct map *m;
+
+	down_read(&maps->lock);
+
+	p = maps->entries.rb_node;
+	while (p != NULL) {
+		m = rb_entry(p, struct map, rb_node);
+		if (ip < m->start)
+			p = p->rb_left;
+		else if (ip >= m->end)
+			p = p->rb_right;
+		else
+			goto out;
+	}
+
+	m = NULL;
+out:
+	up_read(&maps->lock);
+	return m;
+}
+
+struct map *maps__first(struct maps *maps)
+{
+	struct rb_node *first = rb_first(&maps->entries);
+
+	if (first)
+		return rb_entry(first, struct map, rb_node);
+	return NULL;
+}
+
+static struct map *__map__next(struct map *map)
+{
+	struct rb_node *next = rb_next(&map->rb_node);
+
+	if (next)
+		return rb_entry(next, struct map, rb_node);
+	return NULL;
+}
+
+struct map *map__next(struct map *map)
+{
+	return map ? __map__next(map) : NULL;
+}
+
+struct kmap *__map__kmap(struct map *map)
+{
+	if (!map->dso || !map->dso->kernel)
+		return NULL;
+	return (struct kmap *)(map + 1);
+}
+
+struct kmap *map__kmap(struct map *map)
+{
+	struct kmap *kmap = __map__kmap(map);
+
+	if (!kmap)
+		pr_err("Internal error: map__kmap with a non-kernel map\n");
+	return kmap;
+}
+
+struct maps *map__kmaps(struct map *map)
+{
+	struct kmap *kmap = map__kmap(map);
+
+	if (!kmap || !kmap->kmaps) {
+		pr_err("Internal error: map__kmaps with a non-kernel map\n");
+		return NULL;
+	}
+	return kmap->kmaps;
+}