@@ -1363,7 +1363,7 @@ int cmd_grep(int argc,
 			odb_prepare_alternates(the_repository->objects);
 			for (source = the_repository->objects->sources; source; source = source->next) {
 				struct odb_source_files *files = odb_source_files_downcast(source);
-				packfile_store_prepare(files->packed);
+				odb_source_packed_prepare(files->packed);
 			}
 		}
 

@@ -102,7 +102,7 @@ static int midx_read_object_offsets(const unsigned char *chunk_start,
 struct multi_pack_index *get_multi_pack_index(struct odb_source *source)
 {
 	struct odb_source_files *files = odb_source_files_downcast(source);
-	packfile_store_prepare(files->packed);
+	odb_source_packed_prepare(files->packed);
 	return files->packed->midx;
 }
 

@@ -45,7 +45,7 @@ static void odb_source_files_reprepare(struct odb_source *source)
 {
 	struct odb_source_files *files = odb_source_files_downcast(source);
 	odb_source_reprepare(&files->loose->base);
-	packfile_store_reprepare(files->packed);
+	odb_source_reprepare(&files->packed->base);
 }
 
 static int odb_source_files_read_object_info(struct odb_source *source,

@@ -1,10 +1,166 @@
 #include "git-compat-util.h"
 #include "abspath.h"
 #include "chdir-notify.h"
+#include "dir.h"
+#include "mergesort.h"
 #include "midx.h"
 #include "odb/source-packed.h"
 #include "packfile.h"
 
+void (*report_garbage)(unsigned seen_bits, const char *path);
+
+static void report_helper(const struct string_list *list,
+			  int seen_bits, int first, int last)
+{
+	if (seen_bits == (PACKDIR_FILE_PACK|PACKDIR_FILE_IDX))
+		return;
+
+	for (; first < last; first++)
+		report_garbage(seen_bits, list->items[first].string);
+}
+
+static void report_pack_garbage(struct string_list *list)
+{
+	int baselen = -1, first = 0, seen_bits = 0;
+
+	if (!report_garbage)
+		return;
+
+	string_list_sort(list);
+
+	for (size_t i = 0; i < list->nr; i++) {
+		const char *path = list->items[i].string;
+		if (baselen != -1 &&
+		    strncmp(path, list->items[first].string, baselen)) {
+			report_helper(list, seen_bits, first, i);
+			baselen = -1;
+			seen_bits = 0;
+		}
+		if (baselen == -1) {
+			const char *dot = strrchr(path, '.');
+			if (!dot) {
+				report_garbage(PACKDIR_FILE_GARBAGE, path);
+				continue;
+			}
+			baselen = dot - path + 1;
+			first = i;
+		}
+		if (!strcmp(path + baselen, "pack"))
+			seen_bits |= 1;
+		else if (!strcmp(path + baselen, "idx"))
+			seen_bits |= 2;
+	}
+	report_helper(list, seen_bits, first, list->nr);
+}
+
+struct prepare_pack_data {
+	struct odb_source *source;
+	struct string_list *garbage;
+};
+
+static void prepare_pack(const char *full_name, size_t full_name_len,
+			 const char *file_name, void *_data)
+{
+	struct prepare_pack_data *data = (struct prepare_pack_data *)_data;
+	struct odb_source_files *files = odb_source_files_downcast(data->source);
+	size_t base_len = full_name_len;
+
+	if (strip_suffix_mem(full_name, &base_len, ".idx") &&
+	    !(files->packed->midx &&
+	      midx_contains_pack(files->packed->midx, file_name))) {
+		char *trimmed_path = xstrndup(full_name, full_name_len);
+		packfile_store_load_pack(files->packed,
+					 trimmed_path, data->source->local);
+		free(trimmed_path);
+	}
+
+	if (!report_garbage)
+		return;
+
+	if (!strcmp(file_name, "multi-pack-index") ||
+	    !strcmp(file_name, "multi-pack-index.d"))
+		return;
+	if (starts_with(file_name, "multi-pack-index") &&
+	    (ends_with(file_name, ".bitmap") || ends_with(file_name, ".rev")))
+		return;
+	if (ends_with(file_name, ".idx") ||
+	    ends_with(file_name, ".rev") ||
+	    ends_with(file_name, ".pack") ||
+	    ends_with(file_name, ".bitmap") ||
+	    ends_with(file_name, ".keep") ||
+	    ends_with(file_name, ".promisor") ||
+	    ends_with(file_name, ".mtimes"))
+		string_list_append(data->garbage, full_name);
+	else
+		report_garbage(PACKDIR_FILE_GARBAGE, full_name);
+}
+
+static void prepare_packed_git_one(struct odb_source *source)
+{
+	struct string_list garbage = STRING_LIST_INIT_DUP;
+	struct prepare_pack_data data = {
+		.source = source,
+		.garbage = &garbage,
+	};
+
+	for_each_file_in_pack_dir(source->path, prepare_pack, &data);
+
+	report_pack_garbage(data.garbage);
+	string_list_clear(data.garbage, 0);
+}
+
+DEFINE_LIST_SORT(static, sort_packs, struct packfile_list_entry, next);
+
+static int sort_pack(const struct packfile_list_entry *a,
+		     const struct packfile_list_entry *b)
+{
+	int st;
+
+	/*
+	 * Local packs tend to contain objects specific to our
+	 * variant of the project than remote ones.  In addition,
+	 * remote ones could be on a network mounted filesystem.
+	 * Favor local ones for these reasons.
+	 */
+	st = a->pack->pack_local - b->pack->pack_local;
+	if (st)
+		return -st;
+
+	/*
+	 * Younger packs tend to contain more recent objects,
+	 * and more recent objects tend to get accessed more
+	 * often.
+	 */
+	if (a->pack->mtime < b->pack->mtime)
+		return 1;
+	else if (a->pack->mtime == b->pack->mtime)
+		return 0;
+	return -1;
+}
+
+void odb_source_packed_prepare(struct odb_source_packed *source)
+{
+	if (source->initialized)
+		return;
+
+	prepare_multi_pack_index_one(&source->files->base);
+	prepare_packed_git_one(&source->files->base);
+
+	sort_packs(&source->packs.head, sort_pack);
+	for (struct packfile_list_entry *e = source->packs.head; e; e = e->next)
+		if (!e->next)
+			source->packs.tail = e;
+
+	source->initialized = true;
+}
+
+static void odb_source_packed_reprepare(struct odb_source *source)
+{
+	struct odb_source_packed *packed = odb_source_packed_downcast(source);
+	packed->initialized = false;
+	odb_source_packed_prepare(packed);
+}
+
 static void odb_source_packed_reparent(const char *name UNUSED,
 				       const char *old_cwd,
 				       const char *new_cwd,

@@ -58,6 +214,7 @@ struct odb_source_packed *odb_source_packed_new(struct odb_source_files *parent)
 
 	packed->base.free = odb_source_packed_free;
 	packed->base.close = odb_source_packed_close;
+	packed->base.reprepare = odb_source_packed_reprepare;
 
 	if (!is_absolute_path(parent->base.path))
 		chdir_notify_register(NULL, odb_source_packed_reparent, packed);

@@ -81,4 +81,13 @@ static inline struct odb_source_packed *odb_source_packed_downcast(struct odb_so
 	return container_of(source, struct odb_source_packed, base);
 }
 
+/*
+ * Prepare the source by loading packfiles and multi-pack indices for
+ * all alternates. This becomes a no-op if the source is already prepared.
+ *
+ * It shouldn't typically be necessary to call this function directly, as
+ * functions that access the source know to prepare it.
+ */
+void odb_source_packed_prepare(struct odb_source_packed *source);
+
 #endif

@@ -8,7 +8,6 @@
 #include "pack.h"
 #include "repository.h"
 #include "dir.h"
-#include "mergesort.h"
 #include "packfile.h"
 #include "delta.h"
 #include "hash-lookup.h"

@@ -812,52 +811,6 @@ struct packed_git *packfile_store_load_pack(struct odb_source_packed *store,
 	return p;
 }
 
-void (*report_garbage)(unsigned seen_bits, const char *path);
-
-static void report_helper(const struct string_list *list,
-			  int seen_bits, int first, int last)
-{
-	if (seen_bits == (PACKDIR_FILE_PACK|PACKDIR_FILE_IDX))
-		return;
-
-	for (; first < last; first++)
-		report_garbage(seen_bits, list->items[first].string);
-}
-
-static void report_pack_garbage(struct string_list *list)
-{
-	int i, baselen = -1, first = 0, seen_bits = 0;
-
-	if (!report_garbage)
-		return;
-
-	string_list_sort(list);
-
-	for (i = 0; i < list->nr; i++) {
-		const char *path = list->items[i].string;
-		if (baselen != -1 &&
-		    strncmp(path, list->items[first].string, baselen)) {
-			report_helper(list, seen_bits, first, i);
-			baselen = -1;
-			seen_bits = 0;
-		}
-		if (baselen == -1) {
-			const char *dot = strrchr(path, '.');
-			if (!dot) {
-				report_garbage(PACKDIR_FILE_GARBAGE, path);
-				continue;
-			}
-			baselen = dot - path + 1;
-			first = i;
-		}
-		if (!strcmp(path + baselen, "pack"))
-			seen_bits |= 1;
-		else if (!strcmp(path + baselen, "idx"))
-			seen_bits |= 2;
-	}
-	report_helper(list, seen_bits, first, list->nr);
-}
-
 void for_each_file_in_pack_subdir(const char *objdir,
 				  const char *subdir,
 				  each_file_in_pack_dir_fn fn,

@@ -900,116 +853,9 @@ void for_each_file_in_pack_dir(const char *objdir,
 	for_each_file_in_pack_subdir(objdir, NULL, fn, data);
 }
 
-struct prepare_pack_data {
-	struct odb_source *source;
-	struct string_list *garbage;
-};
-
-static void prepare_pack(const char *full_name, size_t full_name_len,
-			 const char *file_name, void *_data)
-{
-	struct prepare_pack_data *data = (struct prepare_pack_data *)_data;
-	struct odb_source_files *files = odb_source_files_downcast(data->source);
-	size_t base_len = full_name_len;
-
-	if (strip_suffix_mem(full_name, &base_len, ".idx") &&
-	    !(files->packed->midx &&
-	      midx_contains_pack(files->packed->midx, file_name))) {
-		char *trimmed_path = xstrndup(full_name, full_name_len);
-		packfile_store_load_pack(files->packed,
-					 trimmed_path, data->source->local);
-		free(trimmed_path);
-	}
-
-	if (!report_garbage)
-		return;
-
-	if (!strcmp(file_name, "multi-pack-index") ||
-	    !strcmp(file_name, "multi-pack-index.d"))
-		return;
-	if (starts_with(file_name, "multi-pack-index") &&
-	    (ends_with(file_name, ".bitmap") || ends_with(file_name, ".rev")))
-		return;
-	if (ends_with(file_name, ".idx") ||
-	    ends_with(file_name, ".rev") ||
-	    ends_with(file_name, ".pack") ||
-	    ends_with(file_name, ".bitmap") ||
-	    ends_with(file_name, ".keep") ||
-	    ends_with(file_name, ".promisor") ||
-	    ends_with(file_name, ".mtimes"))
-		string_list_append(data->garbage, full_name);
-	else
-		report_garbage(PACKDIR_FILE_GARBAGE, full_name);
-}
-
-static void prepare_packed_git_one(struct odb_source *source)
-{
-	struct string_list garbage = STRING_LIST_INIT_DUP;
-	struct prepare_pack_data data = {
-		.source = source,
-		.garbage = &garbage,
-	};
-
-	for_each_file_in_pack_dir(source->path, prepare_pack, &data);
-
-	report_pack_garbage(data.garbage);
-	string_list_clear(data.garbage, 0);
-}
-
-DEFINE_LIST_SORT(static, sort_packs, struct packfile_list_entry, next);
-
-static int sort_pack(const struct packfile_list_entry *a,
-		     const struct packfile_list_entry *b)
-{
-	int st;
-
-	/*
-	 * Local packs tend to contain objects specific to our
-	 * variant of the project than remote ones.  In addition,
-	 * remote ones could be on a network mounted filesystem.
-	 * Favor local ones for these reasons.
-	 */
-	st = a->pack->pack_local - b->pack->pack_local;
-	if (st)
-		return -st;
-
-	/*
-	 * Younger packs tend to contain more recent objects,
-	 * and more recent objects tend to get accessed more
-	 * often.
-	 */
-	if (a->pack->mtime < b->pack->mtime)
-		return 1;
-	else if (a->pack->mtime == b->pack->mtime)
-		return 0;
-	return -1;
-}
-
-void packfile_store_prepare(struct odb_source_packed *store)
-{
-	if (store->initialized)
-		return;
-
-	prepare_multi_pack_index_one(&store->files->base);
-	prepare_packed_git_one(&store->files->base);
-
-	sort_packs(&store->packs.head, sort_pack);
-	for (struct packfile_list_entry *e = store->packs.head; e; e = e->next)
-		if (!e->next)
-			store->packs.tail = e;
-
-	store->initialized = true;
-}
-
-void packfile_store_reprepare(struct odb_source_packed *store)
-{
-	store->initialized = false;
-	packfile_store_prepare(store);
-}
-
 struct packfile_list_entry *packfile_store_get_packs(struct odb_source_packed *store)
 {
-	packfile_store_prepare(store);
+	odb_source_packed_prepare(store);
 
 	if (store->midx) {
 		struct multi_pack_index *m = store->midx;

@@ -2083,7 +1929,7 @@ static int find_pack_entry(struct odb_source_packed *store,
 {
 	struct packfile_list_entry *l;
 
-	packfile_store_prepare(store);
+	odb_source_packed_prepare(store);
 	if (store->midx && fill_midx_entry(store->midx, oid, e))
 		return 1;
 

@@ -2130,7 +1976,7 @@ int packfile_store_read_object_info(struct odb_source_packed *store,
 	 * been added since the last time we have prepared the packfile store.
 	 */
 	if (flags & OBJECT_INFO_SECOND_READ)
-		packfile_store_reprepare(store);
+		odb_source_reprepare(&store->base);
 
 	if (!find_pack_entry(store, oid, &e))
 		return 1;

@@ -55,23 +55,6 @@ struct packed_git {
 	char pack_name[FLEX_ARRAY]; /* more */
 };
 
-/*
- * Prepare the packfile store by loading packfiles and multi-pack indices for
- * all alternates. This becomes a no-op if the store is already prepared.
- *
- * It shouldn't typically be necessary to call this function directly, as
- * functions that access the store know to prepare it.
- */
-void packfile_store_prepare(struct odb_source_packed *store);
-
-/*
- * Clear the packfile caches and try to look up any new packfiles that have
- * appeared since last preparing the packfiles store.
- *
- * This function must be called under the `odb_read_lock()`.
- */
-void packfile_store_reprepare(struct odb_source_packed *store);
-
 /*
  * Add the pack to the store so that contained objects become accessible via
  * the store. This moves ownership into the store.