perf maps: Move maps code to own C file

The maps code has its own header, move the corresponding C function
definitions to their own C file. In the process tidy and minimize
includes.

Committer notes:

Add back the 'static' for maps__init() and maps__exit().

Signed-off-by: Ian Rogers <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Alexey Bayduraev <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: André Almeida <[e-mail]>
Cc: Andy Shevchenko <[e-mail]>
Cc: Darren Hart <[e-mail]>
Cc: Davidlohr Bueso <[e-mail]>
Cc: Dmitriy Vyukov <[e-mail]>
Cc: Eric Dumazet <[e-mail]>
Cc: German Gomez <[e-mail]>
Cc: Hao Luo <[e-mail]>
Cc: James Clark <[e-mail]>
Cc: Jin Yao <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: John Garry <[e-mail]>
Cc: Kajol Jain <[e-mail]>
Cc: Kan Liang <[e-mail]>
Cc: Leo Yan <[e-mail]>
Cc: Madhavan Srinivasan <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Miaoqian Lin <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Riccardo Mancini <[e-mail]>
Cc: Shunsuke Nakamura <[e-mail]>
Cc: Song Liu <[e-mail]>
Cc: Stephane Eranian <[e-mail]>
Cc: Stephen Brennan <[e-mail]>
Cc: Steven Rostedt (VMware) <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Thomas Richter <[e-mail]>
Cc: Yury Norov <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/Build

···
 perf-y += fncache.o
 perf-y += machine.o
 perf-y += map.o
+perf-y += maps.o
 perf-y += pstack.o
 perf-y += session.o
 perf-y += sample-raw.o

tools/perf/util/map.c

···
 // SPDX-License-Identifier: GPL-2.0
-#include "symbol.h"
-#include <assert.h>
-#include <errno.h>
 #include <inttypes.h>
 #include <limits.h>
+#include <stdio.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 <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
+#include "debug.h"
+#include "dso.h"
+#include "map.h"
 #include "namespaces.h"
-#include "unwind.h"
-#include "srccode.h"
-#include "ui/ui.h"
-
-static void __maps__insert(struct maps *maps, struct map *map);
+#include "srcline.h"
+#include "symbol.h"
+#include "thread.h"
+#include "vdso.h"
 
 static inline int is_android_lib(const char *filename)
 {
···
 	return ip + map->reloc;
 }
 
-static 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);
-	}
-}
-
-static 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)
+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)

tools/perf/util/map.h

···
 
 bool map__has_symbols(const struct map *map);
 
+bool map__contains_symbol(struct map *map, struct symbol *sym);
+
 #define ENTRY_TRAMPOLINE_NAME "__entry_SYSCALL_64_trampoline"
 
 static inline bool is_entry_trampoline(const char *name)

tools/perf/util/maps.c

···
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <stdlib.h>
+#include <linux/zalloc.h>
+#include "debug.h"
+#include "dso.h"
+#include "map.h"
+#include "maps.h"
+#include "thread.h"
+#include "ui/ui.h"
+#include "unwind.h"
+
+static void __maps__insert(struct maps *maps, struct map *map);
+
+static 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);
+	}
+}
+
+static 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;
+}
+
+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;
+}