pack-bitmap: remove bitmap_git global variable
[git/git.git] / pack-bitmap.c
index 18f8b22..70465b8 100644 (file)
@@ -25,14 +25,14 @@ struct stored_bitmap {
 };
 
 /*
- * The currently active bitmap index. By design, repositories only have
+ * The active bitmap index for a repository. By design, repositories only have
  * a single bitmap index available (the index for the biggest packfile in
  * the repository), since bitmap indexes need full closure.
  *
  * If there is more than one bitmap index available (e.g. because of alternates),
  * the active bitmap index is the largest one.
  */
-static struct bitmap_index {
+struct bitmap_index {
        /* Packfile to which this bitmap index belongs to */
        struct packed_git *pack;
 
@@ -90,8 +90,7 @@ static struct bitmap_index {
        unsigned int version;
 
        unsigned loaded : 1;
-
-} bitmap_git;
+};
 
 static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)
 {
@@ -259,7 +258,7 @@ static char *pack_bitmap_filename(struct packed_git *p)
        return xstrfmt("%.*s.bitmap", (int)len, p->pack_name);
 }
 
-static int open_pack_bitmap_1(struct packed_git *packfile)
+static int open_pack_bitmap_1(struct bitmap_index *bitmap_git, struct packed_git *packfile)
 {
        int fd;
        struct stat st;
@@ -280,117 +279,121 @@ static int open_pack_bitmap_1(struct packed_git *packfile)
                return -1;
        }
 
-       if (bitmap_git.pack) {
+       if (bitmap_git->pack) {
                warning("ignoring extra bitmap file: %s", packfile->pack_name);
                close(fd);
                return -1;
        }
 
-       bitmap_git.pack = packfile;
-       bitmap_git.map_size = xsize_t(st.st_size);
-       bitmap_git.map = xmmap(NULL, bitmap_git.map_size, PROT_READ, MAP_PRIVATE, fd, 0);
-       bitmap_git.map_pos = 0;
+       bitmap_git->pack = packfile;
+       bitmap_git->map_size = xsize_t(st.st_size);
+       bitmap_git->map = xmmap(NULL, bitmap_git->map_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       bitmap_git->map_pos = 0;
        close(fd);
 
-       if (load_bitmap_header(&bitmap_git) < 0) {
-               munmap(bitmap_git.map, bitmap_git.map_size);
-               bitmap_git.map = NULL;
-               bitmap_git.map_size = 0;
+       if (load_bitmap_header(bitmap_git) < 0) {
+               munmap(bitmap_git->map, bitmap_git->map_size);
+               bitmap_git->map = NULL;
+               bitmap_git->map_size = 0;
                return -1;
        }
 
        return 0;
 }
 
-static int load_pack_bitmap(void)
+static int load_pack_bitmap(struct bitmap_index *bitmap_git)
 {
-       assert(bitmap_git.map && !bitmap_git.loaded);
+       assert(bitmap_git->map && !bitmap_git->loaded);
 
-       bitmap_git.bitmaps = kh_init_sha1();
-       bitmap_git.ext_index.positions = kh_init_sha1_pos();
-       load_pack_revindex(bitmap_git.pack);
+       bitmap_git->bitmaps = kh_init_sha1();
+       bitmap_git->ext_index.positions = kh_init_sha1_pos();
+       load_pack_revindex(bitmap_git->pack);
 
-       if (!(bitmap_git.commits = read_bitmap_1(&bitmap_git)) ||
-               !(bitmap_git.trees = read_bitmap_1(&bitmap_git)) ||
-               !(bitmap_git.blobs = read_bitmap_1(&bitmap_git)) ||
-               !(bitmap_git.tags = read_bitmap_1(&bitmap_git)))
+       if (!(bitmap_git->commits = read_bitmap_1(bitmap_git)) ||
+               !(bitmap_git->trees = read_bitmap_1(bitmap_git)) ||
+               !(bitmap_git->blobs = read_bitmap_1(bitmap_git)) ||
+               !(bitmap_git->tags = read_bitmap_1(bitmap_git)))
                goto failed;
 
-       if (load_bitmap_entries_v1(&bitmap_git) < 0)
+       if (load_bitmap_entries_v1(bitmap_git) < 0)
                goto failed;
 
-       bitmap_git.loaded = 1;
+       bitmap_git->loaded = 1;
        return 0;
 
 failed:
-       munmap(bitmap_git.map, bitmap_git.map_size);
-       bitmap_git.map = NULL;
-       bitmap_git.map_size = 0;
+       munmap(bitmap_git->map, bitmap_git->map_size);
+       bitmap_git->map = NULL;
+       bitmap_git->map_size = 0;
        return -1;
 }
 
-static int open_pack_bitmap(void)
+static int open_pack_bitmap(struct bitmap_index *bitmap_git)
 {
        struct packed_git *p;
        int ret = -1;
 
-       assert(!bitmap_git.map && !bitmap_git.loaded);
+       assert(!bitmap_git->map && !bitmap_git->loaded);
 
        for (p = get_packed_git(the_repository); p; p = p->next) {
-               if (open_pack_bitmap_1(p) == 0)
+               if (open_pack_bitmap_1(bitmap_git, p) == 0)
                        ret = 0;
        }
 
        return ret;
 }
 
-int prepare_bitmap_git(void)
+struct bitmap_index *prepare_bitmap_git(void)
 {
-       if (bitmap_git.loaded)
-               return 0;
+       struct bitmap_index *bitmap_git = xcalloc(1, sizeof(*bitmap_git));
 
-       if (!open_pack_bitmap())
-               return load_pack_bitmap();
+       if (!open_pack_bitmap(bitmap_git) && !load_pack_bitmap(bitmap_git))
+               return bitmap_git;
 
-       return -1;
+       return NULL;
 }
 
 struct include_data {
+       struct bitmap_index *bitmap_git;
        struct bitmap *base;
        struct bitmap *seen;
 };
 
-static inline int bitmap_position_extended(const unsigned char *sha1)
+static inline int bitmap_position_extended(struct bitmap_index *bitmap_git,
+                                          const unsigned char *sha1)
 {
-       khash_sha1_pos *positions = bitmap_git.ext_index.positions;
+       khash_sha1_pos *positions = bitmap_git->ext_index.positions;
        khiter_t pos = kh_get_sha1_pos(positions, sha1);
 
        if (pos < kh_end(positions)) {
                int bitmap_pos = kh_value(positions, pos);
-               return bitmap_pos + bitmap_git.pack->num_objects;
+               return bitmap_pos + bitmap_git->pack->num_objects;
        }
 
        return -1;
 }
 
-static inline int bitmap_position_packfile(const unsigned char *sha1)
+static inline int bitmap_position_packfile(struct bitmap_index *bitmap_git,
+                                          const unsigned char *sha1)
 {
-       off_t offset = find_pack_entry_one(sha1, bitmap_git.pack);
+       off_t offset = find_pack_entry_one(sha1, bitmap_git->pack);
        if (!offset)
                return -1;
 
-       return find_revindex_position(bitmap_git.pack, offset);
+       return find_revindex_position(bitmap_git->pack, offset);
 }
 
-static int bitmap_position(const unsigned char *sha1)
+static int bitmap_position(struct bitmap_index *bitmap_git,
+                          const unsigned char *sha1)
 {
-       int pos = bitmap_position_packfile(sha1);
-       return (pos >= 0) ? pos : bitmap_position_extended(sha1);
+       int pos = bitmap_position_packfile(bitmap_git, sha1);
+       return (pos >= 0) ? pos : bitmap_position_extended(bitmap_git, sha1);
 }
 
-static int ext_index_add_object(struct object *object, const char *name)
+static int ext_index_add_object(struct bitmap_index *bitmap_git,
+                               struct object *object, const char *name)
 {
-       struct eindex *eindex = &bitmap_git.ext_index;
+       struct eindex *eindex = &bitmap_git->ext_index;
 
        khiter_t hash_pos;
        int hash_ret;
@@ -413,27 +416,34 @@ static int ext_index_add_object(struct object *object, const char *name)
                bitmap_pos = kh_value(eindex->positions, hash_pos);
        }
 
-       return bitmap_pos + bitmap_git.pack->num_objects;
+       return bitmap_pos + bitmap_git->pack->num_objects;
 }
 
-static void show_object(struct object *object, const char *name, void *data)
+struct bitmap_show_data {
+       struct bitmap_index *bitmap_git;
+       struct bitmap *base;
+};
+
+static void show_object(struct object *object, const char *name, void *data_)
 {
-       struct bitmap *base = data;
+       struct bitmap_show_data *data = data_;
        int bitmap_pos;
 
-       bitmap_pos = bitmap_position(object->oid.hash);
+       bitmap_pos = bitmap_position(data->bitmap_git, object->oid.hash);
 
        if (bitmap_pos < 0)
-               bitmap_pos = ext_index_add_object(object, name);
+               bitmap_pos = ext_index_add_object(data->bitmap_git, object,
+                                                 name);
 
-       bitmap_set(base, bitmap_pos);
+       bitmap_set(data->base, bitmap_pos);
 }
 
 static void show_commit(struct commit *commit, void *data)
 {
 }
 
-static int add_to_include_set(struct include_data *data,
+static int add_to_include_set(struct bitmap_index *bitmap_git,
+                             struct include_data *data,
                              const unsigned char *sha1,
                              int bitmap_pos)
 {
@@ -445,9 +455,9 @@ static int add_to_include_set(struct include_data *data,
        if (bitmap_get(data->base, bitmap_pos))
                return 0;
 
-       hash_pos = kh_get_sha1(bitmap_git.bitmaps, sha1);
-       if (hash_pos < kh_end(bitmap_git.bitmaps)) {
-               struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, hash_pos);
+       hash_pos = kh_get_sha1(bitmap_git->bitmaps, sha1);
+       if (hash_pos < kh_end(bitmap_git->bitmaps)) {
+               struct stored_bitmap *st = kh_value(bitmap_git->bitmaps, hash_pos);
                bitmap_or_ewah(data->base, lookup_stored_bitmap(st));
                return 0;
        }
@@ -461,11 +471,14 @@ static int should_include(struct commit *commit, void *_data)
        struct include_data *data = _data;
        int bitmap_pos;
 
-       bitmap_pos = bitmap_position(commit->object.oid.hash);
+       bitmap_pos = bitmap_position(data->bitmap_git, commit->object.oid.hash);
        if (bitmap_pos < 0)
-               bitmap_pos = ext_index_add_object((struct object *)commit, NULL);
+               bitmap_pos = ext_index_add_object(data->bitmap_git,
+                                                 (struct object *)commit,
+                                                 NULL);
 
-       if (!add_to_include_set(data, commit->object.oid.hash, bitmap_pos)) {
+       if (!add_to_include_set(data->bitmap_git, data, commit->object.oid.hash,
+                               bitmap_pos)) {
                struct commit_list *parent = commit->parents;
 
                while (parent) {
@@ -479,7 +492,8 @@ static int should_include(struct commit *commit, void *_data)
        return 1;
 }
 
-static struct bitmap *find_objects(struct rev_info *revs,
+static struct bitmap *find_objects(struct bitmap_index *bitmap_git,
+                                  struct rev_info *revs,
                                   struct object_list *roots,
                                   struct bitmap *seen)
 {
@@ -501,10 +515,10 @@ static struct bitmap *find_objects(struct rev_info *revs,
                roots = roots->next;
 
                if (object->type == OBJ_COMMIT) {
-                       khiter_t pos = kh_get_sha1(bitmap_git.bitmaps, object->oid.hash);
+                       khiter_t pos = kh_get_sha1(bitmap_git->bitmaps, object->oid.hash);
 
-                       if (pos < kh_end(bitmap_git.bitmaps)) {
-                               struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
+                       if (pos < kh_end(bitmap_git->bitmaps)) {
+                               struct stored_bitmap *st = kh_value(bitmap_git->bitmaps, pos);
                                struct ewah_bitmap *or_with = lookup_stored_bitmap(st);
 
                                if (base == NULL)
@@ -543,7 +557,7 @@ static struct bitmap *find_objects(struct rev_info *revs,
                int pos;
 
                roots = roots->next;
-               pos = bitmap_position(object->oid.hash);
+               pos = bitmap_position(bitmap_git, object->oid.hash);
 
                if (pos < 0 || base == NULL || !bitmap_get(base, pos)) {
                        object->flags &= ~UNINTERESTING;
@@ -556,10 +570,12 @@ static struct bitmap *find_objects(struct rev_info *revs,
 
        if (needs_walk) {
                struct include_data incdata;
+               struct bitmap_show_data show_data;
 
                if (base == NULL)
                        base = bitmap_new();
 
+               incdata.bitmap_git = bitmap_git;
                incdata.base = base;
                incdata.seen = seen;
 
@@ -569,22 +585,27 @@ static struct bitmap *find_objects(struct rev_info *revs,
                if (prepare_revision_walk(revs))
                        die("revision walk setup failed");
 
-               traverse_commit_list(revs, show_commit, show_object, base);
+               show_data.bitmap_git = bitmap_git;
+               show_data.base = base;
+
+               traverse_commit_list(revs, show_commit, show_object,
+                                    &show_data);
        }
 
        return base;
 }
 
-static void show_extended_objects(struct bitmap *objects,
+static void show_extended_objects(struct bitmap_index *bitmap_git,
                                  show_reachable_fn show_reach)
 {
-       struct eindex *eindex = &bitmap_git.ext_index;
+       struct bitmap *objects = bitmap_git->result;
+       struct eindex *eindex = &bitmap_git->ext_index;
        uint32_t i;
 
        for (i = 0; i < eindex->count; ++i) {
                struct object *obj;
 
-               if (!bitmap_get(objects, bitmap_git.pack->num_objects + i))
+               if (!bitmap_get(objects, bitmap_git->pack->num_objects + i))
                        continue;
 
                obj = eindex->objects[i];
@@ -593,7 +614,7 @@ static void show_extended_objects(struct bitmap *objects,
 }
 
 static void show_objects_for_type(
-       struct bitmap *objects,
+       struct bitmap_index *bitmap_git,
        struct ewah_bitmap *type_filter,
        enum object_type object_type,
        show_reachable_fn show_reach)
@@ -604,7 +625,9 @@ static void show_objects_for_type(
        struct ewah_iterator it;
        eword_t filter;
 
-       if (bitmap_git.reuse_objects == bitmap_git.pack->num_objects)
+       struct bitmap *objects = bitmap_git->result;
+
+       if (bitmap_git->reuse_objects == bitmap_git->pack->num_objects)
                return;
 
        ewah_iterator_init(&it, type_filter);
@@ -622,16 +645,16 @@ static void show_objects_for_type(
 
                        offset += ewah_bit_ctz64(word >> offset);
 
-                       if (pos + offset < bitmap_git.reuse_objects)
+                       if (pos + offset < bitmap_git->reuse_objects)
                                continue;
 
-                       entry = &bitmap_git.pack->revindex[pos + offset];
-                       nth_packed_object_oid(&oid, bitmap_git.pack, entry->nr);
+                       entry = &bitmap_git->pack->revindex[pos + offset];
+                       nth_packed_object_oid(&oid, bitmap_git->pack, entry->nr);
 
-                       if (bitmap_git.hashes)
-                               hash = get_be32(bitmap_git.hashes + entry->nr);
+                       if (bitmap_git->hashes)
+                               hash = get_be32(bitmap_git->hashes + entry->nr);
 
-                       show_reach(&oid, object_type, 0, hash, bitmap_git.pack, entry->offset);
+                       show_reach(&oid, object_type, 0, hash, bitmap_git->pack, entry->offset);
                }
 
                pos += BITS_IN_EWORD;
@@ -639,20 +662,21 @@ static void show_objects_for_type(
        }
 }
 
-static int in_bitmapped_pack(struct object_list *roots)
+static int in_bitmapped_pack(struct bitmap_index *bitmap_git,
+                            struct object_list *roots)
 {
        while (roots) {
                struct object *object = roots->item;
                roots = roots->next;
 
-               if (find_pack_entry_one(object->oid.hash, bitmap_git.pack) > 0)
+               if (find_pack_entry_one(object->oid.hash, bitmap_git->pack) > 0)
                        return 1;
        }
 
        return 0;
 }
 
-int prepare_bitmap_walk(struct rev_info *revs)
+struct bitmap_index *prepare_bitmap_walk(struct rev_info *revs)
 {
        unsigned int i;
 
@@ -662,12 +686,11 @@ int prepare_bitmap_walk(struct rev_info *revs)
        struct bitmap *wants_bitmap = NULL;
        struct bitmap *haves_bitmap = NULL;
 
-       if (!bitmap_git.loaded) {
-               /* try to open a bitmapped pack, but don't parse it yet
-                * because we may not need to use it */
-               if (open_pack_bitmap() < 0)
-                       return -1;
-       }
+       struct bitmap_index *bitmap_git = xcalloc(1, sizeof(*bitmap_git));
+       /* try to open a bitmapped pack, but don't parse it yet
+        * because we may not need to use it */
+       if (open_pack_bitmap(bitmap_git) < 0)
+               return NULL;
 
        for (i = 0; i < revs->pending.nr; ++i) {
                struct object *object = revs->pending.objects[i].item;
@@ -699,26 +722,26 @@ int prepare_bitmap_walk(struct rev_info *revs)
         * in the packfile that has a bitmap, we don't have anything to
         * optimize here
         */
-       if (haves && !in_bitmapped_pack(haves))
-               return -1;
+       if (haves && !in_bitmapped_pack(bitmap_git, haves))
+               return NULL;
 
        /* if we don't want anything, we're done here */
        if (!wants)
-               return -1;
+               return NULL;
 
        /*
         * now we're going to use bitmaps, so load the actual bitmap entries
         * from disk. this is the point of no return; after this the rev_list
         * becomes invalidated and we must perform the revwalk through bitmaps
         */
-       if (!bitmap_git.loaded && load_pack_bitmap() < 0)
-               return -1;
+       if (!bitmap_git->loaded && load_pack_bitmap(bitmap_git) < 0)
+               return NULL;
 
        object_array_clear(&revs->pending);
 
        if (haves) {
                revs->ignore_missing_links = 1;
-               haves_bitmap = find_objects(revs, haves, NULL);
+               haves_bitmap = find_objects(bitmap_git, revs, haves, NULL);
                reset_revision_walk();
                revs->ignore_missing_links = 0;
 
@@ -726,7 +749,7 @@ int prepare_bitmap_walk(struct rev_info *revs)
                        BUG("failed to perform bitmap walk");
        }
 
-       wants_bitmap = find_objects(revs, wants, haves_bitmap);
+       wants_bitmap = find_objects(bitmap_git, revs, wants, haves_bitmap);
 
        if (!wants_bitmap)
                BUG("failed to perform bitmap walk");
@@ -734,13 +757,14 @@ int prepare_bitmap_walk(struct rev_info *revs)
        if (haves_bitmap)
                bitmap_and_not(wants_bitmap, haves_bitmap);
 
-       bitmap_git.result = wants_bitmap;
+       bitmap_git->result = wants_bitmap;
 
        bitmap_free(haves_bitmap);
-       return 0;
+       return bitmap_git;
 }
 
-int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
+int reuse_partial_packfile_from_bitmap(struct bitmap_index *bitmap_git,
+                                      struct packed_git **packfile,
                                       uint32_t *entries,
                                       off_t *up_to)
 {
@@ -750,7 +774,7 @@ int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
         */
        static const double REUSE_PERCENT = 0.9;
 
-       struct bitmap *result = bitmap_git.result;
+       struct bitmap *result = bitmap_git->result;
        uint32_t reuse_threshold;
        uint32_t i, reuse_objects = 0;
 
@@ -770,8 +794,8 @@ int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
                const unsigned char *sha1;
                struct revindex_entry *entry;
 
-               entry = &bitmap_git.reverse_index->revindex[reuse_objects];
-               sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
+               entry = &bitmap_git->reverse_index->revindex[reuse_objects];
+               sha1 = nth_packed_object_sha1(bitmap_git->pack, entry->nr);
 
                fprintf(stderr, "Failed to reuse at %d (%016llx)\n",
                        reuse_objects, result->words[i]);
@@ -782,48 +806,50 @@ int reuse_partial_packfile_from_bitmap(struct packed_git **packfile,
        if (!reuse_objects)
                return -1;
 
-       if (reuse_objects >= bitmap_git.pack->num_objects) {
-               bitmap_git.reuse_objects = *entries = bitmap_git.pack->num_objects;
+       if (reuse_objects >= bitmap_git->pack->num_objects) {
+               bitmap_git->reuse_objects = *entries = bitmap_git->pack->num_objects;
                *up_to = -1; /* reuse the full pack */
-               *packfile = bitmap_git.pack;
+               *packfile = bitmap_git->pack;
                return 0;
        }
 
-       reuse_threshold = bitmap_popcount(bitmap_git.result) * REUSE_PERCENT;
+       reuse_threshold = bitmap_popcount(bitmap_git->result) * REUSE_PERCENT;
 
        if (reuse_objects < reuse_threshold)
                return -1;
 
-       bitmap_git.reuse_objects = *entries = reuse_objects;
-       *up_to = bitmap_git.pack->revindex[reuse_objects].offset;
-       *packfile = bitmap_git.pack;
+       bitmap_git->reuse_objects = *entries = reuse_objects;
+       *up_to = bitmap_git->pack->revindex[reuse_objects].offset;
+       *packfile = bitmap_git->pack;
 
        return 0;
 }
 
-void traverse_bitmap_commit_list(show_reachable_fn show_reachable)
+void traverse_bitmap_commit_list(struct bitmap_index *bitmap_git,
+                                show_reachable_fn show_reachable)
 {
-       assert(bitmap_git.result);
+       assert(bitmap_git->result);
 
-       show_objects_for_type(bitmap_git.result, bitmap_git.commits,
+       show_objects_for_type(bitmap_git, bitmap_git->commits,
                OBJ_COMMIT, show_reachable);
-       show_objects_for_type(bitmap_git.result, bitmap_git.trees,
+       show_objects_for_type(bitmap_git, bitmap_git->trees,
                OBJ_TREE, show_reachable);
-       show_objects_for_type(bitmap_git.result, bitmap_git.blobs,
+       show_objects_for_type(bitmap_git, bitmap_git->blobs,
                OBJ_BLOB, show_reachable);
-       show_objects_for_type(bitmap_git.result, bitmap_git.tags,
+       show_objects_for_type(bitmap_git, bitmap_git->tags,
                OBJ_TAG, show_reachable);
 
-       show_extended_objects(bitmap_git.result, show_reachable);
+       show_extended_objects(bitmap_git, show_reachable);
 
-       bitmap_free(bitmap_git.result);
-       bitmap_git.result = NULL;
+       bitmap_free(bitmap_git->result);
+       bitmap_git->result = NULL;
 }
 
-static uint32_t count_object_type(struct bitmap *objects,
+static uint32_t count_object_type(struct bitmap_index *bitmap_git,
                                  enum object_type type)
 {
-       struct eindex *eindex = &bitmap_git.ext_index;
+       struct bitmap *objects = bitmap_git->result;
+       struct eindex *eindex = &bitmap_git->ext_index;
 
        uint32_t i = 0, count = 0;
        struct ewah_iterator it;
@@ -831,19 +857,19 @@ static uint32_t count_object_type(struct bitmap *objects,
 
        switch (type) {
        case OBJ_COMMIT:
-               ewah_iterator_init(&it, bitmap_git.commits);
+               ewah_iterator_init(&it, bitmap_git->commits);
                break;
 
        case OBJ_TREE:
-               ewah_iterator_init(&it, bitmap_git.trees);
+               ewah_iterator_init(&it, bitmap_git->trees);
                break;
 
        case OBJ_BLOB:
-               ewah_iterator_init(&it, bitmap_git.blobs);
+               ewah_iterator_init(&it, bitmap_git->blobs);
                break;
 
        case OBJ_TAG:
-               ewah_iterator_init(&it, bitmap_git.tags);
+               ewah_iterator_init(&it, bitmap_git->tags);
                break;
 
        default:
@@ -857,32 +883,34 @@ static uint32_t count_object_type(struct bitmap *objects,
 
        for (i = 0; i < eindex->count; ++i) {
                if (eindex->objects[i]->type == type &&
-                       bitmap_get(objects, bitmap_git.pack->num_objects + i))
+                       bitmap_get(objects, bitmap_git->pack->num_objects + i))
                        count++;
        }
 
        return count;
 }
 
-void count_bitmap_commit_list(uint32_t *commits, uint32_t *trees,
+void count_bitmap_commit_list(struct bitmap_index *bitmap_git,
+                             uint32_t *commits, uint32_t *trees,
                              uint32_t *blobs, uint32_t *tags)
 {
-       assert(bitmap_git.result);
+       assert(bitmap_git->result);
 
        if (commits)
-               *commits = count_object_type(bitmap_git.result, OBJ_COMMIT);
+               *commits = count_object_type(bitmap_git, OBJ_COMMIT);
 
        if (trees)
-               *trees = count_object_type(bitmap_git.result, OBJ_TREE);
+               *trees = count_object_type(bitmap_git, OBJ_TREE);
 
        if (blobs)
-               *blobs = count_object_type(bitmap_git.result, OBJ_BLOB);
+               *blobs = count_object_type(bitmap_git, OBJ_BLOB);
 
        if (tags)
-               *tags = count_object_type(bitmap_git.result, OBJ_TAG);
+               *tags = count_object_type(bitmap_git, OBJ_TAG);
 }
 
 struct bitmap_test_data {
+       struct bitmap_index *bitmap_git;
        struct bitmap *base;
        struct progress *prg;
        size_t seen;
@@ -894,7 +922,7 @@ static void test_show_object(struct object *object, const char *name,
        struct bitmap_test_data *tdata = data;
        int bitmap_pos;
 
-       bitmap_pos = bitmap_position(object->oid.hash);
+       bitmap_pos = bitmap_position(tdata->bitmap_git, object->oid.hash);
        if (bitmap_pos < 0)
                die("Object not in bitmap: %s\n", oid_to_hex(&object->oid));
 
@@ -907,7 +935,8 @@ static void test_show_commit(struct commit *commit, void *data)
        struct bitmap_test_data *tdata = data;
        int bitmap_pos;
 
-       bitmap_pos = bitmap_position(commit->object.oid.hash);
+       bitmap_pos = bitmap_position(tdata->bitmap_git,
+                                    commit->object.oid.hash);
        if (bitmap_pos < 0)
                die("Object not in bitmap: %s\n", oid_to_hex(&commit->object.oid));
 
@@ -922,21 +951,22 @@ void test_bitmap_walk(struct rev_info *revs)
        khiter_t pos;
        size_t result_popcnt;
        struct bitmap_test_data tdata;
+       struct bitmap_index *bitmap_git;
 
-       if (prepare_bitmap_git())
+       if (!(bitmap_git = prepare_bitmap_git()))
                die("failed to load bitmap indexes");
 
        if (revs->pending.nr != 1)
                die("you must specify exactly one commit to test");
 
        fprintf(stderr, "Bitmap v%d test (%d entries loaded)\n",
-               bitmap_git.version, bitmap_git.entry_count);
+               bitmap_git->version, bitmap_git->entry_count);
 
        root = revs->pending.objects[0].item;
-       pos = kh_get_sha1(bitmap_git.bitmaps, root->oid.hash);
+       pos = kh_get_sha1(bitmap_git->bitmaps, root->oid.hash);
 
-       if (pos < kh_end(bitmap_git.bitmaps)) {
-               struct stored_bitmap *st = kh_value(bitmap_git.bitmaps, pos);
+       if (pos < kh_end(bitmap_git->bitmaps)) {
+               struct stored_bitmap *st = kh_value(bitmap_git->bitmaps, pos);
                struct ewah_bitmap *bm = lookup_stored_bitmap(st);
 
                fprintf(stderr, "Found bitmap for %s. %d bits / %08x checksum\n",
@@ -957,6 +987,7 @@ void test_bitmap_walk(struct rev_info *revs)
        if (prepare_revision_walk(revs))
                die("revision walk setup failed");
 
+       tdata.bitmap_git = bitmap_git;
        tdata.base = bitmap_new();
        tdata.prg = start_progress("Verifying bitmap entries", result_popcnt);
        tdata.seen = 0;
@@ -1004,7 +1035,8 @@ static int rebuild_bitmap(uint32_t *reposition,
        return 0;
 }
 
-int rebuild_existing_bitmaps(struct packing_data *mapping,
+int rebuild_existing_bitmaps(struct bitmap_index *bitmap_git,
+                            struct packing_data *mapping,
                             khash_sha1 *reused_bitmaps,
                             int show_progress)
 {
@@ -1017,10 +1049,7 @@ int rebuild_existing_bitmaps(struct packing_data *mapping,
        khiter_t hash_pos;
        int hash_ret;
 
-       if (prepare_bitmap_git() < 0)
-               return -1;
-
-       num_objects = bitmap_git.pack->num_objects;
+       num_objects = bitmap_git->pack->num_objects;
        reposition = xcalloc(num_objects, sizeof(uint32_t));
 
        for (i = 0; i < num_objects; ++i) {
@@ -1028,8 +1057,8 @@ int rebuild_existing_bitmaps(struct packing_data *mapping,
                struct revindex_entry *entry;
                struct object_entry *oe;
 
-               entry = &bitmap_git.pack->revindex[i];
-               sha1 = nth_packed_object_sha1(bitmap_git.pack, entry->nr);
+               entry = &bitmap_git->pack->revindex[i];
+               sha1 = nth_packed_object_sha1(bitmap_git->pack, entry->nr);
                oe = packlist_find(mapping, sha1, NULL);
 
                if (oe)
@@ -1042,7 +1071,7 @@ int rebuild_existing_bitmaps(struct packing_data *mapping,
        if (show_progress)
                progress = start_progress("Reusing bitmaps", 0);
 
-       kh_foreach_value(bitmap_git.bitmaps, stored, {
+       kh_foreach_value(bitmap_git->bitmaps, stored, {
                if (stored->flags & BITMAP_FLAG_REUSE) {
                        if (!rebuild_bitmap(reposition,
                                            lookup_stored_bitmap(stored),