diff --git a/Makefile b/Makefile
index 13f9062a05..0b46dee0da 100644
--- a/Makefile
+++ b/Makefile
@@ -994,6 +994,7 @@ LIB_OBJS += common-exit.o
 LIB_OBJS += common-init.o
 LIB_OBJS += compat/nonblock.o
 LIB_OBJS += compat/obstack.o
+LIB_OBJS += compat/open.o
 LIB_OBJS += compat/terminal.o
 LIB_OBJS += compiler-tricks/not-constant.o
 LIB_OBJS += config.o
@@ -1084,6 +1085,7 @@ LIB_OBJS += notes.o
 LIB_OBJS += object-file-convert.o
 LIB_OBJS += object-file.o
 LIB_OBJS += object-name.o
+LIB_OBJS += object-store.o
 LIB_OBJS += object.o
 LIB_OBJS += oid-array.o
 LIB_OBJS += oidmap.o
@@ -1811,7 +1813,6 @@ ifdef FREAD_READS_DIRECTORIES
 endif
 ifdef OPEN_RETURNS_EINTR
 	COMPAT_CFLAGS += -DOPEN_RETURNS_EINTR
-	COMPAT_OBJS += compat/open.o
 endif
 ifdef NO_SYMLINK_HEAD
 	BASIC_CFLAGS += -DNO_SYMLINK_HEAD
diff --git a/apply.c b/apply.c
index f274a37948..2b6f4d0af8 100644
--- a/apply.c
+++ b/apply.c
@@ -14,7 +14,7 @@
 #include "abspath.h"
 #include "base85.h"
 #include "config.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "delta.h"
 #include "diff.h"
 #include "dir.h"
diff --git a/archive-tar.c b/archive-tar.c
index 0edf13fba7..282b48196f 100644
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -11,7 +11,7 @@
 #include "hex.h"
 #include "tar.h"
 #include "archive.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strbuf.h"
 #include "streaming.h"
 #include "run-command.h"
diff --git a/archive-zip.c b/archive-zip.c
index 9f32730181..405da6f3d8 100644
--- a/archive-zip.c
+++ b/archive-zip.c
@@ -12,7 +12,7 @@
 #include "hex.h"
 #include "streaming.h"
 #include "utf8.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strbuf.h"
 #include "userdiff.h"
 #include "write-or-die.h"
diff --git a/archive.c b/archive.c
index c95e398152..014c312178 100644
--- a/archive.c
+++ b/archive.c
@@ -14,7 +14,7 @@
 #include "pretty.h"
 #include "setup.h"
 #include "refs.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "tree.h"
 #include "tree-walk.h"
diff --git a/attr.c b/attr.c
index 0bd2750528..86b6109fc4 100644
--- a/attr.c
+++ b/attr.c
@@ -22,7 +22,7 @@
 #include "read-cache-ll.h"
 #include "refs.h"
 #include "revision.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "setup.h"
 #include "thread-utils.h"
 #include "tree-walk.h"
diff --git a/bisect.c b/bisect.c
index 269a98bf97..a327468c75 100644
--- a/bisect.c
+++ b/bisect.c
@@ -20,7 +20,7 @@
 #include "commit-slab.h"
 #include "commit-reach.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "dir.h"
 
diff --git a/blame.c b/blame.c
index 703dab43e7..57daa45e89 100644
--- a/blame.c
+++ b/blame.c
@@ -3,7 +3,7 @@
 
 #include "git-compat-util.h"
 #include "refs.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "cache-tree.h"
 #include "mergesort.h"
 #include "commit.h"
@@ -277,7 +277,7 @@ static struct commit *fake_working_tree_commit(struct repository *r,
 	convert_to_git(r->index, path, buf.buf, buf.len, &buf, 0);
 	origin->file.ptr = buf.buf;
 	origin->file.size = buf.len;
-	pretend_object_file(buf.buf, buf.len, OBJ_BLOB, &origin->blob_oid);
+	pretend_object_file(the_repository, buf.buf, buf.len, OBJ_BLOB, &origin->blob_oid);
 
 	/*
 	 * Read the current index, replace the path entry with
diff --git a/builtin/backfill.c b/builtin/backfill.c
index 33e1ea2f84..aaa104bc91 100644
--- a/builtin/backfill.c
+++ b/builtin/backfill.c
@@ -13,7 +13,7 @@
 #include "tree.h"
 #include "tree-walk.h"
 #include "object.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "oidset.h"
 #include "promisor-remote.h"
diff --git a/builtin/blame.c b/builtin/blame.c
index 9436f70aec..5bf11c2a3c 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -28,7 +28,7 @@
 #include "line-log.h"
 #include "progress.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pager.h"
 #include "blame.h"
 #include "refs.h"
diff --git a/builtin/bugreport.c b/builtin/bugreport.c
index 66d64bfd5a..f78c3f2aed 100644
--- a/builtin/bugreport.c
+++ b/builtin/bugreport.c
@@ -4,13 +4,13 @@
 #include "editor.h"
 #include "gettext.h"
 #include "parse-options.h"
+#include "path.h"
 #include "strbuf.h"
 #include "help.h"
 #include "compat/compiler.h"
 #include "hook.h"
 #include "hook-list.h"
 #include "diagnose.h"
-#include "object-file.h"
 #include "setup.h"
 #include "version.h"
 
@@ -141,7 +141,7 @@ int cmd_bugreport(int argc,
 	}
 	strbuf_addstr(&report_path, ".txt");
 
-	switch (safe_create_leading_directories(report_path.buf)) {
+	switch (safe_create_leading_directories(the_repository, report_path.buf)) {
 	case SCLD_OK:
 	case SCLD_EXISTS:
 		break;
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index ead7554a57..0e3f10a946 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -24,7 +24,7 @@
 #include "pack-bitmap.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "promisor-remote.h"
 #include "mailmap.h"
diff --git a/builtin/checkout.c b/builtin/checkout.c
index e69ea06713..d185982f3a 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -18,8 +18,9 @@
 #include "lockfile.h"
 #include "mem-pool.h"
 #include "merge-ort-wrappers.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "parse-options.h"
 #include "path.h"
 #include "preload-index.h"
diff --git a/builtin/clone.c b/builtin/clone.c
index 7d5b64a6a0..6b1d11a3ed 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -25,7 +25,7 @@
 #include "refs.h"
 #include "refspec.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "tree.h"
 #include "tree-walk.h"
 #include "unpack-trees.h"
@@ -1092,7 +1092,7 @@ int cmd_clone(int argc,
 	sigchain_push_common(remove_junk_on_signal);
 
 	if (!option_bare) {
-		if (safe_create_leading_directories_const(work_tree) < 0)
+		if (safe_create_leading_directories_const(the_repository, work_tree) < 0)
 			die_errno(_("could not create leading directories of '%s'"),
 				  work_tree);
 		if (dest_exists)
@@ -1113,7 +1113,7 @@ int cmd_clone(int argc,
 			junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 		junk_git_dir = git_dir;
 	}
-	if (safe_create_leading_directories_const(git_dir) < 0)
+	if (safe_create_leading_directories_const(the_repository, git_dir) < 0)
 		die(_("could not create leading directories of '%s'"), git_dir);
 
 	if (0 <= option_verbosity) {
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 8ca75262c5..be06d0a811 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -6,7 +6,7 @@
 #include "hex.h"
 #include "parse-options.h"
 #include "commit-graph.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "progress.h"
 #include "replace-object.h"
 #include "strbuf.h"
diff --git a/builtin/commit-tree.c b/builtin/commit-tree.c
index 38457600a4..6f9975e7a8 100644
--- a/builtin/commit-tree.c
+++ b/builtin/commit-tree.c
@@ -9,7 +9,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 #include "commit.h"
 #include "parse-options.h"
diff --git a/builtin/count-objects.c b/builtin/count-objects.c
index 1e89148ed7..0bb5360b2f 100644
--- a/builtin/count-objects.c
+++ b/builtin/count-objects.c
@@ -12,7 +12,7 @@
 #include "parse-options.h"
 #include "quote.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 static unsigned long garbage;
 static off_t size_garbage;
diff --git a/builtin/credential-cache--daemon.c b/builtin/credential-cache--daemon.c
index e707618e74..5065ff4660 100644
--- a/builtin/credential-cache--daemon.c
+++ b/builtin/credential-cache--daemon.c
@@ -2,8 +2,8 @@
 #include "builtin.h"
 #include "abspath.h"
 #include "gettext.h"
-#include "object-file.h"
 #include "parse-options.h"
+#include "path.h"
 
 #ifndef NO_UNIX_SOCKETS
 
@@ -271,7 +271,7 @@ static void init_socket_directory(const char *path)
 		 * condition in which somebody can chdir to it, sleep, then try to open
 		 * our protected socket.
 		 */
-		if (safe_create_leading_directories_const(dir) < 0)
+		if (safe_create_leading_directories_const(the_repository, dir) < 0)
 			die_errno("unable to create directories for '%s'", dir);
 		if (mkdir(dir, 0700) < 0)
 			die_errno("unable to mkdir '%s'", dir);
diff --git a/builtin/describe.c b/builtin/describe.c
index 23df333fd0..0f87fbceef 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -19,7 +19,7 @@
 #include "setup.h"
 #include "strvec.h"
 #include "run-command.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "list-objects.h"
 #include "commit-slab.h"
 #include "wildmatch.h"
diff --git a/builtin/diagnose.c b/builtin/diagnose.c
index 33c39bd598..ec86d66389 100644
--- a/builtin/diagnose.c
+++ b/builtin/diagnose.c
@@ -3,8 +3,8 @@
 #include "builtin.h"
 #include "abspath.h"
 #include "gettext.h"
-#include "object-file.h"
 #include "parse-options.h"
+#include "path.h"
 #include "diagnose.h"
 
 static const char * const diagnose_usage[] = {
@@ -50,7 +50,7 @@ int cmd_diagnose(int argc,
 	strbuf_addftime(&zip_path, option_suffix, localtime_r(&now, &tm), 0, 0);
 	strbuf_addstr(&zip_path, ".zip");
 
-	switch (safe_create_leading_directories(zip_path.buf)) {
+	switch (safe_create_leading_directories(the_repository, zip_path.buf)) {
 	case SCLD_OK:
 	case SCLD_EXISTS:
 		break;
diff --git a/builtin/difftool.c b/builtin/difftool.c
index 41cd00066c..f17a55b3cf 100644
--- a/builtin/difftool.c
+++ b/builtin/difftool.c
@@ -22,6 +22,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "parse-options.h"
+#include "path.h"
 #include "read-cache-ll.h"
 #include "repository.h"
 #include "sparse-index.h"
@@ -29,7 +30,7 @@
 #include "strbuf.h"
 #include "lockfile.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "dir.h"
 #include "entry.h"
 #include "setup.h"
@@ -271,9 +272,9 @@ static void changed_files(struct repository *repo,
 	strbuf_release(&buf);
 }
 
-static int ensure_leading_directories(char *path)
+static int ensure_leading_directories(struct repository *repo, char *path)
 {
-	switch (safe_create_leading_directories(path)) {
+	switch (safe_create_leading_directories(repo, path)) {
 		case SCLD_OK:
 		case SCLD_EXISTS:
 			return 0;
@@ -341,11 +342,12 @@ static int checkout_path(unsigned mode, struct object_id *oid,
 	return ret;
 }
 
-static void write_file_in_directory(struct strbuf *dir, size_t dir_len,
-			const char *path, const char *content)
+static void write_file_in_directory(struct repository *repo,
+				    struct strbuf *dir, size_t dir_len,
+				    const char *path, const char *content)
 {
 	add_path(dir, dir_len, path);
-	ensure_leading_directories(dir->buf);
+	ensure_leading_directories(repo, dir->buf);
 	unlink(dir->buf);
 	write_file(dir->buf, "%s", content);
 }
@@ -356,14 +358,15 @@ static void write_file_in_directory(struct strbuf *dir, size_t dir_len,
  * as text files, resulting in behavior that is analogous to what "git diff"
  * displays for symlink and submodule diffs.
  */
-static void write_standin_files(struct pair_entry *entry,
-			struct strbuf *ldir, size_t ldir_len,
-			struct strbuf *rdir, size_t rdir_len)
+static void write_standin_files(struct repository *repo,
+				struct pair_entry *entry,
+				struct strbuf *ldir, size_t ldir_len,
+				struct strbuf *rdir, size_t rdir_len)
 {
 	if (*entry->left)
-		write_file_in_directory(ldir, ldir_len, entry->path, entry->left);
+		write_file_in_directory(repo, ldir, ldir_len, entry->path, entry->left);
 	if (*entry->right)
-		write_file_in_directory(rdir, rdir_len, entry->path, entry->right);
+		write_file_in_directory(repo, rdir, rdir_len, entry->path, entry->right);
 }
 
 static int run_dir_diff(struct repository *repo,
@@ -533,7 +536,7 @@ static int run_dir_diff(struct repository *repo,
 						ADD_CACHE_JUST_APPEND);
 
 				add_path(&rdir, rdir_len, dst_path);
-				if (ensure_leading_directories(rdir.buf)) {
+				if (ensure_leading_directories(repo, rdir.buf)) {
 					ret = error("could not create "
 						    "directory for '%s'",
 						    dst_path);
@@ -576,7 +579,7 @@ static int run_dir_diff(struct repository *repo,
 	 */
 	hashmap_for_each_entry(&submodules, &iter, entry,
 				entry /* member name */) {
-		write_standin_files(entry, &ldir, ldir_len, &rdir, rdir_len);
+		write_standin_files(repo, entry, &ldir, ldir_len, &rdir, rdir_len);
 	}
 
 	/*
@@ -587,7 +590,7 @@ static int run_dir_diff(struct repository *repo,
 	hashmap_for_each_entry(&symlinks2, &iter, entry,
 				entry /* member name */) {
 
-		write_standin_files(entry, &ldir, ldir_len, &rdir, rdir_len);
+		write_standin_files(repo, entry, &ldir, ldir_len, &rdir, rdir_len);
 	}
 
 	strbuf_setlen(&ldir, ldir_len);
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 170126d41a..afacd228b5 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -14,7 +14,7 @@
 #include "refs.h"
 #include "refspec.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "object.h"
 #include "tag.h"
diff --git a/builtin/fast-import.c b/builtin/fast-import.c
index 63880b595c..c1e198f4e3 100644
--- a/builtin/fast-import.c
+++ b/builtin/fast-import.c
@@ -24,7 +24,7 @@
 #include "packfile.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "mem-pool.h"
 #include "commit-reach.h"
 #include "khash.h"
@@ -1720,7 +1720,7 @@ static void dump_marks(void)
 	if (!export_marks_file || (import_marks_file && !import_marks_file_done))
 		return;
 
-	if (safe_create_leading_directories_const(export_marks_file)) {
+	if (safe_create_leading_directories_const(the_repository, export_marks_file)) {
 		failure |= error_errno("unable to create leading directories of %s",
 				       export_marks_file);
 		return;
diff --git a/builtin/fetch.c b/builtin/fetch.c
index 097a98628f..95589b4994 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -14,7 +14,7 @@
 #include "refs.h"
 #include "refspec.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oidset.h"
 #include "oid-array.h"
 #include "commit.h"
diff --git a/builtin/fsck.c b/builtin/fsck.c
index 9c8a6d6a8d..6cac28356c 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -17,7 +17,7 @@
 #include "packfile.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "read-cache-ll.h"
 #include "replace-object.h"
@@ -332,7 +332,7 @@ static void check_unreachable_object(struct object *obj)
 				describe_object(&obj->oid));
 			FILE *f;
 
-			if (safe_create_leading_directories_const(filename)) {
+			if (safe_create_leading_directories_const(the_repository, filename)) {
 				error(_("could not create lost-found"));
 				free(filename);
 				return;
diff --git a/builtin/gc.c b/builtin/gc.c
index d5c75be252..b5ce1d3276 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -28,8 +28,7 @@
 #include "commit.h"
 #include "commit-graph.h"
 #include "packfile.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pack.h"
 #include "pack-objects.h"
 #include "path.h"
@@ -2169,7 +2168,7 @@ static int launchctl_schedule_plist(const char *exec_path, enum schedule_priorit
 	}
 	strbuf_addstr(&plist, "</array>\n</dict>\n</plist>\n");
 
-	if (safe_create_leading_directories(filename))
+	if (safe_create_leading_directories(the_repository, filename))
 		die(_("failed to create directories for '%s'"), filename);
 
 	if ((long)lock_file_timeout_ms < 0 &&
@@ -2635,7 +2634,7 @@ static int systemd_timer_write_timer_file(enum schedule_priority schedule,
 
 	filename = xdg_config_home_systemd(local_timer_name);
 
-	if (safe_create_leading_directories(filename)) {
+	if (safe_create_leading_directories(the_repository, filename)) {
 		error(_("failed to create directories for '%s'"), filename);
 		goto error;
 	}
@@ -2708,7 +2707,7 @@ static int systemd_timer_write_service_template(const char *exec_path)
 	char *local_service_name = xstrfmt(SYSTEMD_UNIT_FORMAT, "", "service");
 
 	filename = xdg_config_home_systemd(local_service_name);
-	if (safe_create_leading_directories(filename)) {
+	if (safe_create_leading_directories(the_repository, filename)) {
 		error(_("failed to create directories for '%s'"), filename);
 		goto error;
 	}
diff --git a/builtin/grep.c b/builtin/grep.c
index 283d64cab8..bcfbe5be5b 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -26,7 +26,7 @@
 #include "submodule-config.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "pager.h"
 #include "path.h"
diff --git a/builtin/hash-object.c b/builtin/hash-object.c
index a25f0403f4..cd53fa3bde 100644
--- a/builtin/hash-object.c
+++ b/builtin/hash-object.c
@@ -11,7 +11,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "blob.h"
 #include "quote.h"
 #include "parse-options.h"
@@ -19,6 +19,11 @@
 #include "strbuf.h"
 #include "write-or-die.h"
 
+enum {
+	HASH_OBJECT_CHECK = (1 << 0),
+	HASH_OBJECT_WRITE = (1 << 1),
+};
+
 /*
  * This is to create corrupt objects for debugging and as such it
  * needs to bypass the data conversion performed by, and the type
@@ -33,7 +38,7 @@ static int hash_literally(struct object_id *oid, int fd, const char *type, unsig
 		ret = -1;
 	else
 		ret = write_object_file_literally(buf.buf, buf.len, type, oid,
-						 flags);
+						  (flags & HASH_OBJECT_WRITE) ? WRITE_OBJECT_FILE_PERSIST : 0);
 	close(fd);
 	strbuf_release(&buf);
 	return ret;
@@ -42,15 +47,21 @@ static int hash_literally(struct object_id *oid, int fd, const char *type, unsig
 static void hash_fd(int fd, const char *type, const char *path, unsigned flags,
 		    int literally)
 {
+	unsigned int index_flags = 0;
 	struct stat st;
 	struct object_id oid;
 
+	if (flags & HASH_OBJECT_WRITE)
+		index_flags |= INDEX_WRITE_OBJECT;
+	if (flags & HASH_OBJECT_CHECK)
+		index_flags |= INDEX_FORMAT_CHECK;
+
 	if (fstat(fd, &st) < 0 ||
 	    (literally
 	     ? hash_literally(&oid, fd, type, flags)
 	     : index_fd(the_repository->index, &oid, fd, &st,
-			type_from_string(type), path, flags)))
-		die((flags & HASH_WRITE_OBJECT)
+			type_from_string(type), path, index_flags)))
+		die((flags & HASH_OBJECT_WRITE)
 		    ? "Unable to add %s to database"
 		    : "Unable to hash %s", path);
 	printf("%s\n", oid_to_hex(&oid));
@@ -102,13 +113,13 @@ int cmd_hash_object(int argc,
 	int no_filters = 0;
 	int literally = 0;
 	int nongit = 0;
-	unsigned flags = HASH_FORMAT_CHECK;
+	unsigned flags = HASH_OBJECT_CHECK;
 	const char *vpath = NULL;
 	char *vpath_free = NULL;
 	const struct option hash_object_options[] = {
 		OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
 		OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
-			HASH_WRITE_OBJECT),
+			HASH_OBJECT_WRITE),
 		OPT_COUNTUP( 0 , "stdin", &hashstdin, N_("read the object from stdin")),
 		OPT_BOOL( 0 , "stdin-paths", &stdin_paths, N_("read file names from stdin")),
 		OPT_BOOL( 0 , "no-filters", &no_filters, N_("store file as is without filters")),
@@ -122,7 +133,7 @@ int cmd_hash_object(int argc,
 	argc = parse_options(argc, argv, prefix, hash_object_options,
 			     hash_object_usage, 0);
 
-	if (flags & HASH_WRITE_OBJECT)
+	if (flags & HASH_OBJECT_WRITE)
 		prefix = setup_git_directory();
 	else
 		prefix = setup_git_directory_gently(&nongit);
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index de127c0ff1..60a8ee05db 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -21,7 +21,7 @@
 #include "packfile.h"
 #include "pack-revindex.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "oidset.h"
 #include "path.h"
diff --git a/builtin/init-db.c b/builtin/init-db.c
index 196dccdd77..91c2563e34 100644
--- a/builtin/init-db.c
+++ b/builtin/init-db.c
@@ -8,7 +8,6 @@
 #include "abspath.h"
 #include "environment.h"
 #include "gettext.h"
-#include "object-file.h"
 #include "parse-options.h"
 #include "path.h"
 #include "refs.h"
@@ -134,7 +133,7 @@ int cmd_init_db(int argc,
 				 */
 				saved = repo_settings_get_shared_repository(the_repository);
 				repo_settings_set_shared_repository(the_repository, 0);
-				switch (safe_create_leading_directories_const(argv[0])) {
+				switch (safe_create_leading_directories_const(the_repository, argv[0])) {
 				case SCLD_OK:
 				case SCLD_PERMS:
 					break;
diff --git a/builtin/log.c b/builtin/log.c
index 0d4c579dad..b450cd3bde 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -14,9 +14,8 @@
 #include "gettext.h"
 #include "hex.h"
 #include "refs.h"
-#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pager.h"
 #include "color.h"
 #include "commit.h"
@@ -29,6 +28,7 @@
 #include "tag.h"
 #include "reflog-walk.h"
 #include "patch-ids.h"
+#include "path.h"
 #include "shortlog.h"
 #include "remote.h"
 #include "string-list.h"
@@ -2311,7 +2311,7 @@ int cmd_format_patch(int argc,
 		 */
 		saved = repo_settings_get_shared_repository(the_repository);
 		repo_settings_set_shared_repository(the_repository, 0);
-		switch (safe_create_leading_directories_const(output_directory)) {
+		switch (safe_create_leading_directories_const(the_repository, output_directory)) {
 		case SCLD_OK:
 		case SCLD_EXISTS:
 			break;
diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
index 8542b5d53e..8aafc30ca4 100644
--- a/builtin/ls-tree.c
+++ b/builtin/ls-tree.c
@@ -10,7 +10,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "tree.h"
 #include "path.h"
 #include "quote.h"
diff --git a/builtin/merge-file.c b/builtin/merge-file.c
index 7e315f374b..2b16b10d2c 100644
--- a/builtin/merge-file.c
+++ b/builtin/merge-file.c
@@ -5,6 +5,7 @@
 #include "abspath.h"
 #include "diff.h"
 #include "hex.h"
+#include "object-file.h"
 #include "object-name.h"
 #include "object-store.h"
 #include "config.h"
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 3ec7127b3a..4aafa73c61 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -10,7 +10,7 @@
 #include "commit-reach.h"
 #include "merge-ort.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "parse-options.h"
 #include "blob.h"
 #include "merge-blobs.h"
diff --git a/builtin/mktag.c b/builtin/mktag.c
index 6e188dce50..7ac11c46d5 100644
--- a/builtin/mktag.c
+++ b/builtin/mktag.c
@@ -6,7 +6,7 @@
 #include "strbuf.h"
 #include "replace-object.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "fsck.h"
 #include "config.h"
 
diff --git a/builtin/mktree.c b/builtin/mktree.c
index 3c16faa40e..7ffe6eefd8 100644
--- a/builtin/mktree.c
+++ b/builtin/mktree.c
@@ -11,7 +11,8 @@
 #include "strbuf.h"
 #include "tree.h"
 #include "parse-options.h"
-#include "object-store-ll.h"
+#include "object-file.h"
+#include "object-store.h"
 
 static struct treeent {
 	unsigned mode;
diff --git a/builtin/multi-pack-index.c b/builtin/multi-pack-index.c
index 2a938466f5..d98410ca6c 100644
--- a/builtin/multi-pack-index.c
+++ b/builtin/multi-pack-index.c
@@ -7,7 +7,7 @@
 #include "midx.h"
 #include "strbuf.h"
 #include "trace2.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "repository.h"
 
diff --git a/builtin/mv.c b/builtin/mv.c
index d673a6c83e..54b323fff7 100644
--- a/builtin/mv.c
+++ b/builtin/mv.c
@@ -15,6 +15,7 @@
 #include "gettext.h"
 #include "name-hash.h"
 #include "object-file.h"
+#include "path.h"
 #include "pathspec.h"
 #include "lockfile.h"
 #include "dir.h"
@@ -556,7 +557,7 @@ remove_entry:
 					 */
 					char *dst_dup = xstrdup(dst);
 					string_list_append(&dirty_paths, dst);
-					safe_create_leading_directories(dst_dup);
+					safe_create_leading_directories(the_repository, dst_dup);
 					FREE_AND_NULL(dst_dup);
 					rename(src, dst);
 				}
diff --git a/builtin/notes.c b/builtin/notes.c
index ff61ec5f2d..a3f433ca4c 100644
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -14,8 +14,9 @@
 #include "gettext.h"
 #include "hex.h"
 #include "notes.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 
 #include "pretty.h"
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 3973267e9e..8174c60c70 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -32,7 +32,7 @@
 #include "list.h"
 #include "packfile.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "dir.h"
 #include "midx.h"
diff --git a/builtin/pack-redundant.c b/builtin/pack-redundant.c
index 3febe732f8..5d1fc78176 100644
--- a/builtin/pack-redundant.c
+++ b/builtin/pack-redundant.c
@@ -13,7 +13,7 @@
 #include "hex.h"
 
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strbuf.h"
 
 #define BLKSIZE 512
diff --git a/builtin/prune.c b/builtin/prune.c
index 8f52da8bd6..e930caa0c0 100644
--- a/builtin/prune.c
+++ b/builtin/prune.c
@@ -17,7 +17,7 @@
 #include "replace-object.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "shallow.h"
 
 static const char * const prune_usage[] = {
diff --git a/builtin/rebase.c b/builtin/rebase.c
index 965bd048a8..36e336009c 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -267,7 +267,8 @@ static int init_basic_state(struct replay_opts *opts, const char *head_name,
 {
 	FILE *interactive;
 
-	if (!is_directory(merge_dir()) && mkdir_in_gitdir(merge_dir()))
+	if (!is_directory(merge_dir()) &&
+	    safe_create_dir_in_gitdir(the_repository, merge_dir()))
 		return error_errno(_("could not create temporary %s"), merge_dir());
 
 	refs_delete_reflog(get_main_ref_store(the_repository), "REBASE_HEAD");
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index b3e2a9d0c6..be314879e8 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -31,8 +31,9 @@
 #include "tmp-objdir.h"
 #include "oidset.h"
 #include "packfile.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "protocol.h"
 #include "commit-reach.h"
diff --git a/builtin/remote.c b/builtin/remote.c
index d2aeb5ba1f..b4baa34e66 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -14,7 +14,7 @@
 #include "rebase.h"
 #include "refs.h"
 #include "refspec.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strvec.h"
 #include "commit-reach.h"
 #include "progress.h"
diff --git a/builtin/repack.c b/builtin/repack.c
index f3330ade7b..1fd2874324 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -17,7 +17,7 @@
 #include "midx.h"
 #include "packfile.h"
 #include "prune-packed.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "promisor-remote.h"
 #include "shallow.h"
 #include "pack.h"
diff --git a/builtin/replace.c b/builtin/replace.c
index 15ec0922ce..48c7c6a2d5 100644
--- a/builtin/replace.c
+++ b/builtin/replace.c
@@ -19,7 +19,7 @@
 #include "run-command.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "tag.h"
 #include "wildmatch.h"
@@ -305,7 +305,7 @@ static int import_object(struct object_id *oid, enum object_type type,
 		strbuf_release(&result);
 	} else {
 		struct stat st;
-		int flags = HASH_FORMAT_CHECK | HASH_WRITE_OBJECT;
+		int flags = INDEX_FORMAT_CHECK | INDEX_WRITE_OBJECT;
 
 		if (fstat(fd, &st) < 0) {
 			error_errno(_("unable to fstat %s"), filename);
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index 4a84f18f9e..c4cd4ed5c8 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -14,7 +14,7 @@
 #include "object.h"
 #include "object-name.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pack-bitmap.h"
 #include "parse-options.h"
 #include "log-tree.h"
diff --git a/builtin/show-ref.c b/builtin/show-ref.c
index 285cd3e433..f81209f23c 100644
--- a/builtin/show-ref.c
+++ b/builtin/show-ref.c
@@ -5,7 +5,7 @@
 #include "hex.h"
 #include "refs/refs-internal.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "object.h"
 #include "string-list.h"
 #include "parse-options.h"
diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
index 14dcace5f8..1bf01591b2 100644
--- a/builtin/sparse-checkout.c
+++ b/builtin/sparse-checkout.c
@@ -9,6 +9,7 @@
 #include "object-file.h"
 #include "object-name.h"
 #include "parse-options.h"
+#include "path.h"
 #include "pathspec.h"
 #include "strbuf.h"
 #include "string-list.h"
@@ -335,7 +336,7 @@ static int write_patterns_and_update(struct pattern_list *pl)
 
 	sparse_filename = get_sparse_checkout_filename();
 
-	if (safe_create_leading_directories(sparse_filename))
+	if (safe_create_leading_directories(the_repository, sparse_filename))
 		die(_("failed to create directory for sparse-checkout file"));
 
 	hold_lock_file_for_update(&lk, sparse_filename, LOCK_DIE_ON_ERROR);
@@ -491,7 +492,7 @@ static int sparse_checkout_init(int argc, const char **argv, const char *prefix,
 		FILE *fp;
 
 		/* assume we are in a fresh repo, but update the sparse-checkout file */
-		if (safe_create_leading_directories(sparse_filename))
+		if (safe_create_leading_directories(the_repository, sparse_filename))
 			die(_("unable to create leading directories of %s"),
 			    sparse_filename);
 		fp = xfopen(sparse_filename, "w");
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 570226ea16..53da2116dd 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -28,7 +28,7 @@
 #include "diff.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "advice.h"
 #include "branch.h"
 #include "list-objects-filter-options.h"
@@ -1739,7 +1739,7 @@ static int clone_submodule(const struct module_clone_data *clone_data,
 		    !is_empty_dir(clone_data_path))
 			die(_("directory not empty: '%s'"), clone_data_path);
 
-		if (safe_create_leading_directories_const(sm_gitdir) < 0)
+		if (safe_create_leading_directories_const(the_repository, sm_gitdir) < 0)
 			die(_("could not create directory '%s'"), sm_gitdir);
 
 		prepare_possible_alternates(clone_data->name, reference);
@@ -1800,7 +1800,7 @@ static int clone_submodule(const struct module_clone_data *clone_data,
 		if (clone_data->require_init && !stat(clone_data_path, &st) &&
 		    !is_empty_dir(clone_data_path))
 			die(_("directory not empty: '%s'"), clone_data_path);
-		if (safe_create_leading_directories_const(clone_data_path) < 0)
+		if (safe_create_leading_directories_const(the_repository, clone_data_path) < 0)
 			die(_("could not create directory '%s'"), clone_data_path);
 		path = xstrfmt("%s/index", sm_gitdir);
 		unlink_or_warn(path);
diff --git a/builtin/tag.c b/builtin/tag.c
index 7c173535cb..e6b372cebf 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -17,8 +17,9 @@
 #include "gettext.h"
 #include "hex.h"
 #include "refs.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "tag.h"
 #include "parse-options.h"
diff --git a/builtin/unpack-file.c b/builtin/unpack-file.c
index fb5fcbc40a..e33acfc4ee 100644
--- a/builtin/unpack-file.c
+++ b/builtin/unpack-file.c
@@ -2,8 +2,9 @@
 #include "builtin.h"
 #include "config.h"
 #include "hex.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 static char *create_temp_file(struct object_id *oid)
 {
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index 3bbcaf2de9..661be789f1 100644
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -8,7 +8,8 @@
 #include "gettext.h"
 #include "git-zlib.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-file.h"
+#include "object-store.h"
 #include "object.h"
 #include "delta.h"
 #include "pack.h"
diff --git a/builtin/update-index.c b/builtin/update-index.c
index b2f6b1a3fb..f0cf964294 100644
--- a/builtin/update-index.c
+++ b/builtin/update-index.c
@@ -304,7 +304,7 @@ static int add_one_path(const struct cache_entry *old, const char *path, int len
 	ce->ce_mode = ce_mode_from_stat(old, st->st_mode);
 
 	if (index_path(the_repository->index, &ce->oid, path, st,
-		       info_only ? 0 : HASH_WRITE_OBJECT)) {
+		       info_only ? 0 : INDEX_WRITE_OBJECT)) {
 		discard_cache_entry(ce);
 		return -1;
 	}
diff --git a/builtin/worktree.c b/builtin/worktree.c
index 87ccd47794..88a36ea9f8 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -348,7 +348,7 @@ static void copy_sparse_checkout(const char *worktree_git_dir)
 	char *to_file = xstrfmt("%s/info/sparse-checkout", worktree_git_dir);
 
 	if (file_exists(from_file)) {
-		if (safe_create_leading_directories(to_file) ||
+		if (safe_create_leading_directories(the_repository, to_file) ||
 			copy_file(to_file, from_file, 0666))
 			error(_("failed to copy '%s' to '%s'; sparse-checkout may not work correctly"),
 				from_file, to_file);
@@ -367,7 +367,7 @@ static void copy_filtered_worktree_config(const char *worktree_git_dir)
 		struct config_set cs = { { 0 } };
 		int bare;
 
-		if (safe_create_leading_directories(to_file) ||
+		if (safe_create_leading_directories(the_repository, to_file) ||
 			copy_file(to_file, from_file, 0666)) {
 			error(_("failed to copy worktree config from '%s' to '%s'"),
 				from_file, to_file);
@@ -466,7 +466,7 @@ static int add_worktree(const char *path, const char *refname,
 	name = sb_name.buf;
 	repo_git_path_replace(the_repository, &sb_repo, "worktrees/%s", name);
 	len = sb_repo.len;
-	if (safe_create_leading_directories_const(sb_repo.buf))
+	if (safe_create_leading_directories_const(the_repository, sb_repo.buf))
 		die_errno(_("could not create leading directories of '%s'"),
 			  sb_repo.buf);
 
@@ -498,7 +498,7 @@ static int add_worktree(const char *path, const char *refname,
 		write_file(sb.buf, _("initializing"));
 
 	strbuf_addf(&sb_git, "%s/.git", path);
-	if (safe_create_leading_directories_const(sb_git.buf))
+	if (safe_create_leading_directories_const(the_repository, sb_git.buf))
 		die_errno(_("could not create leading directories of '%s'"),
 			  sb_git.buf);
 	junk_work_tree = xstrdup(path);
diff --git a/bulk-checkin.c b/bulk-checkin.c
index 79696e80f2..c31c31b18d 100644
--- a/bulk-checkin.c
+++ b/bulk-checkin.c
@@ -17,7 +17,7 @@
 #include "tmp-objdir.h"
 #include "packfile.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 static int odb_transaction_nesting;
 
@@ -167,7 +167,7 @@ static int stream_blob_to_pack(struct bulk_checkin_packfile *state,
 	unsigned char obuf[16384];
 	unsigned hdrlen;
 	int status = Z_OK;
-	int write_object = (flags & HASH_WRITE_OBJECT);
+	int write_object = (flags & INDEX_WRITE_OBJECT);
 	off_t offset = 0;
 
 	git_deflate_init(&s, pack_compression_level);
@@ -237,7 +237,7 @@ static int stream_blob_to_pack(struct bulk_checkin_packfile *state,
 static void prepare_to_stream(struct bulk_checkin_packfile *state,
 			      unsigned flags)
 {
-	if (!(flags & HASH_WRITE_OBJECT) || state->f)
+	if (!(flags & INDEX_WRITE_OBJECT) || state->f)
 		return;
 
 	state->f = create_tmp_packfile(the_repository, &state->pack_tmp_name);
@@ -271,7 +271,7 @@ static int deflate_blob_to_pack(struct bulk_checkin_packfile *state,
 	git_hash_update(&ctx, obuf, header_len);
 
 	/* Note: idx is non-NULL when we are writing */
-	if ((flags & HASH_WRITE_OBJECT) != 0) {
+	if ((flags & INDEX_WRITE_OBJECT) != 0) {
 		CALLOC_ARRAY(idx, 1);
 
 		prepare_to_stream(state, flags);
diff --git a/bulk-checkin.h b/bulk-checkin.h
index aa7286a7b3..7246ea58dc 100644
--- a/bulk-checkin.h
+++ b/bulk-checkin.h
@@ -9,6 +9,21 @@
 void prepare_loose_object_bulk_checkin(void);
 void fsync_loose_object_bulk_checkin(int fd, const char *filename);
 
+/*
+ * This creates one packfile per large blob unless bulk-checkin
+ * machinery is "plugged".
+ *
+ * This also bypasses the usual "convert-to-git" dance, and that is on
+ * purpose. We could write a streaming version of the converting
+ * functions and insert that before feeding the data to fast-import
+ * (or equivalent in-core API described above). However, that is
+ * somewhat complicated, as we do not know the size of the filter
+ * result, which we need to know beforehand when writing a git object.
+ * Since the primary motivation for trying to stream from the working
+ * tree file and to avoid mmaping it in core is to deal with large
+ * binary blobs, they generally do not want to get any conversion, and
+ * callers should avoid this code path when filters are requested.
+ */
 int index_blob_bulk_checkin(struct object_id *oid,
 			    int fd, size_t size,
 			    const char *path, unsigned flags);
diff --git a/bundle-uri.c b/bundle-uri.c
index 744257c49c..96d2ba726d 100644
--- a/bundle-uri.c
+++ b/bundle-uri.c
@@ -14,7 +14,7 @@
 #include "fetch-pack.h"
 #include "remote.h"
 #include "trace2.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 static struct {
 	enum bundle_list_heuristic heuristic;
diff --git a/bundle.c b/bundle.c
index 0614426e20..b0a3fee2ef 100644
--- a/bundle.c
+++ b/bundle.c
@@ -7,7 +7,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "repository.h"
 #include "object.h"
 #include "commit.h"
diff --git a/cache-tree.c b/cache-tree.c
index bcbcad3d61..c0e1e9ee1d 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -10,7 +10,7 @@
 #include "cache-tree.h"
 #include "bulk-checkin.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "read-cache-ll.h"
 #include "replace-object.h"
 #include "repository.h"
@@ -452,7 +452,7 @@ static int update_one(struct cache_tree *it,
 				 OBJ_TREE, &it->oid);
 	} else if (write_object_file_flags(buffer.buf, buffer.len, OBJ_TREE,
 					   &it->oid, NULL, flags & WRITE_TREE_SILENT
-					   ? HASH_SILENT : 0)) {
+					   ? WRITE_OBJECT_FILE_SILENT : 0)) {
 		strbuf_release(&buffer);
 		return -1;
 	}
diff --git a/combine-diff.c b/combine-diff.c
index 553bf59fed..dfae9f7995 100644
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -2,7 +2,7 @@
 #define DISABLE_SIGN_COMPARE_WARNINGS
 
 #include "git-compat-util.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "convert.h"
 #include "diff.h"
diff --git a/commit-graph.c b/commit-graph.c
index 8286d5dda2..6394752b0b 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -13,8 +13,7 @@
 #include "refs.h"
 #include "hash-lookup.h"
 #include "commit-graph.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "path.h"
 #include "alloc.h"
@@ -2065,7 +2064,7 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx)
 		ctx->graph_name = get_commit_graph_filename(ctx->odb);
 	}
 
-	if (safe_create_leading_directories(ctx->graph_name)) {
+	if (safe_create_leading_directories(the_repository, ctx->graph_name)) {
 		error(_("unable to create leading directories of %s"),
 			ctx->graph_name);
 		return -1;
diff --git a/commit-graph.h b/commit-graph.h
index 6781940195..13f662827d 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -1,7 +1,7 @@
 #ifndef COMMIT_GRAPH_H
 #define COMMIT_GRAPH_H
 
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oidset.h"
 
 #define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
diff --git a/commit.c b/commit.c
index 1f64daa9f4..e915b2b9a1 100644
--- a/commit.c
+++ b/commit.c
@@ -9,7 +9,7 @@
 #include "hex.h"
 #include "repository.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "utf8.h"
 #include "diff.h"
 #include "revision.h"
@@ -29,6 +29,7 @@
 #include "tree.h"
 #include "hook.h"
 #include "parse.h"
+#include "object-file.h"
 #include "object-file-convert.h"
 
 static struct commit_extra_header *read_commit_extra_header_lines(const char *buf, size_t len, const char **);
diff --git a/compat/open.c b/compat/open.c
index eb3754a23b..37ae2b1aeb 100644
--- a/compat/open.c
+++ b/compat/open.c
@@ -1,5 +1,6 @@
 #include "git-compat-util.h"
 
+#ifdef OPEN_RETURNS_EINTR
 #undef open
 int git_open_with_retry(const char *path, int flags, ...)
 {
@@ -23,3 +24,31 @@ int git_open_with_retry(const char *path, int flags, ...)
 
 	return ret;
 }
+#endif
+
+int git_open_cloexec(const char *name, int flags)
+{
+	int fd;
+	static int o_cloexec = O_CLOEXEC;
+
+	fd = open(name, flags | o_cloexec);
+	if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
+		/* Try again w/o O_CLOEXEC: the kernel might not support it */
+		o_cloexec &= ~O_CLOEXEC;
+		fd = open(name, flags | o_cloexec);
+	}
+
+#if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
+	{
+		static int fd_cloexec = FD_CLOEXEC;
+
+		if (!o_cloexec && 0 <= fd && fd_cloexec) {
+			/* Opened w/o O_CLOEXEC?  try with fcntl(2) to add it */
+			int flags = fcntl(fd, F_GETFD);
+			if (fcntl(fd, F_SETFD, flags | fd_cloexec))
+				fd_cloexec = 0;
+		}
+	}
+#endif
+	return fd;
+}
diff --git a/config.c b/config.c
index accb47e2d1..b18b5617fc 100644
--- a/config.c
+++ b/config.c
@@ -31,7 +31,7 @@
 #include "hashmap.h"
 #include "string-list.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pager.h"
 #include "path.h"
 #include "utf8.h"
diff --git a/connected.c b/connected.c
index 3099da84f3..4415388beb 100644
--- a/connected.c
+++ b/connected.c
@@ -3,7 +3,7 @@
 #include "git-compat-util.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "run-command.h"
 #include "sigchain.h"
 #include "connected.h"
diff --git a/convert.c b/convert.c
index 9cc0ca20ca..8783e17941 100644
--- a/convert.c
+++ b/convert.c
@@ -8,7 +8,7 @@
 #include "copy.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "attr.h"
 #include "run-command.h"
 #include "quote.h"
diff --git a/diagnose.c b/diagnose.c
index bd485effea..b1be74be98 100644
--- a/diagnose.c
+++ b/diagnose.c
@@ -7,7 +7,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "strvec.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "parse-options.h"
 #include "repository.h"
diff --git a/diff.c b/diff.c
index 3bcf502883..91d5b962b5 100644
--- a/diff.c
+++ b/diff.c
@@ -23,7 +23,7 @@
 #include "color.h"
 #include "run-command.h"
 #include "utf8.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "userdiff.h"
 #include "submodule.h"
 #include "hashmap.h"
diff --git a/diffcore-rename.c b/diffcore-rename.c
index 8077283fc7..179731462b 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -8,7 +8,7 @@
 #include "git-compat-util.h"
 #include "diff.h"
 #include "diffcore.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "hashmap.h"
 #include "mem-pool.h"
 #include "oid-array.h"
diff --git a/dir.c b/dir.c
index 28b0e03feb..5c4675b4ac 100644
--- a/dir.c
+++ b/dir.c
@@ -17,8 +17,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "name-hash.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "refs.h"
 #include "repository.h"
@@ -4063,12 +4062,12 @@ void connect_work_tree_and_git_dir(const char *work_tree_,
 
 	/* Prepare .git file */
 	strbuf_addf(&gitfile_sb, "%s/.git", work_tree_);
-	if (safe_create_leading_directories_const(gitfile_sb.buf))
+	if (safe_create_leading_directories_const(the_repository, gitfile_sb.buf))
 		die(_("could not create directories for %s"), gitfile_sb.buf);
 
 	/* Prepare config file */
 	strbuf_addf(&cfg_sb, "%s/config", git_dir_);
-	if (safe_create_leading_directories_const(cfg_sb.buf))
+	if (safe_create_leading_directories_const(the_repository, cfg_sb.buf))
 		die(_("could not create directories for %s"), cfg_sb.buf);
 
 	git_dir = real_pathdup(git_dir_, 1);
diff --git a/entry.c b/entry.c
index 81b321e53d..f36ec5ad24 100644
--- a/entry.c
+++ b/entry.c
@@ -1,7 +1,7 @@
 #define USE_THE_REPOSITORY_VARIABLE
 
 #include "git-compat-util.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "dir.h"
 #include "environment.h"
 #include "gettext.h"
diff --git a/fetch-pack.c b/fetch-pack.c
index 1ed5e11dd5..210dc30d50 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -24,7 +24,7 @@
 #include "oid-array.h"
 #include "oidset.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "connected.h"
 #include "fetch-negotiator.h"
diff --git a/fmt-merge-msg.c b/fmt-merge-msg.c
index 5b63c3b088..501b5acdd4 100644
--- a/fmt-merge-msg.c
+++ b/fmt-merge-msg.c
@@ -6,7 +6,7 @@
 #include "environment.h"
 #include "refs.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "diff.h"
 #include "diff-merges.h"
 #include "hex.h"
diff --git a/fsck.c b/fsck.c
index 9fc4c25ffd..8dc8472ceb 100644
--- a/fsck.c
+++ b/fsck.c
@@ -4,7 +4,7 @@
 #include "date.h"
 #include "dir.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "repository.h"
 #include "object.h"
diff --git a/git-compat-util.h b/git-compat-util.h
index afa040086f..591bb78ad9 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -598,6 +598,9 @@ static inline bool strip_suffix(const char *str, const char *suffix,
 #define DEFAULT_PACKED_GIT_LIMIT \
 	((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 
+int git_open_cloexec(const char *name, int flags);
+#define git_open(name) git_open_cloexec(name, O_RDONLY)
+
 static inline size_t st_add(size_t a, size_t b)
 {
 	if (unsigned_add_overflows(a, b))
diff --git a/grep.c b/grep.c
index 9284b5741f..f8d535182c 100644
--- a/grep.c
+++ b/grep.c
@@ -5,7 +5,7 @@
 #include "gettext.h"
 #include "grep.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pretty.h"
 #include "userdiff.h"
 #include "xdiff-interface.h"
diff --git a/http-backend.c b/http-backend.c
index 50b2858fad..0c575aa88a 100644
--- a/http-backend.c
+++ b/http-backend.c
@@ -18,7 +18,7 @@
 #include "url.h"
 #include "strvec.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "protocol.h"
 #include "date.h"
 #include "write-or-die.h"
diff --git a/http-push.c b/http-push.c
index 1b030d96f4..32e37565f4 100644
--- a/http-push.c
+++ b/http-push.c
@@ -19,7 +19,8 @@
 #include "tree-walk.h"
 #include "url.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-file.h"
+#include "object-store.h"
 #include "commit-reach.h"
 
 #ifdef EXPAT_NEEDS_XMLPARSE_H
diff --git a/http-walker.c b/http-walker.c
index 7918ddc096..882cae19c2 100644
--- a/http-walker.c
+++ b/http-walker.c
@@ -9,7 +9,7 @@
 #include "list.h"
 #include "transport.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 struct alt_base {
 	char *base;
diff --git a/http.c b/http.c
index d21e3a3bad..0c41138042 100644
--- a/http.c
+++ b/http.c
@@ -19,7 +19,7 @@
 #include "packfile.h"
 #include "string-list.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "tempfile.h"
 
 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
diff --git a/list-objects-filter.c b/list-objects-filter.c
index dc598a081b..7765761b3c 100644
--- a/list-objects-filter.c
+++ b/list-objects-filter.c
@@ -12,7 +12,7 @@
 #include "oidmap.h"
 #include "oidset.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 /* Remember to update object flag allocation in object.h */
 /*
diff --git a/list-objects.c b/list-objects.c
index 943e62e868..1e5512e131 100644
--- a/list-objects.c
+++ b/list-objects.c
@@ -14,7 +14,7 @@
 #include "list-objects-filter.h"
 #include "list-objects-filter-options.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "trace.h"
 #include "environment.h"
 
diff --git a/log-tree.c b/log-tree.c
index 5dd1b63076..a4d4ab59ca 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -9,7 +9,7 @@
 #include "environment.h"
 #include "hex.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "repository.h"
 #include "tmp-objdir.h"
 #include "commit.h"
diff --git a/mailmap.c b/mailmap.c
index f35d20ed7f..9e2642a043 100644
--- a/mailmap.c
+++ b/mailmap.c
@@ -6,7 +6,7 @@
 #include "string-list.h"
 #include "mailmap.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "setup.h"
 
 char *git_mailmap_file;
diff --git a/match-trees.c b/match-trees.c
index ef14ceb594..72922d5d64 100644
--- a/match-trees.c
+++ b/match-trees.c
@@ -6,7 +6,8 @@
 #include "strbuf.h"
 #include "tree.h"
 #include "tree-walk.h"
-#include "object-store-ll.h"
+#include "object-file.h"
+#include "object-store.h"
 #include "repository.h"
 
 static int score_missing(unsigned mode)
diff --git a/merge-blobs.c b/merge-blobs.c
index 0ad0390fea..53f36dbc17 100644
--- a/merge-blobs.c
+++ b/merge-blobs.c
@@ -4,7 +4,7 @@
 #include "merge-ll.h"
 #include "blob.h"
 #include "merge-blobs.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
 {
diff --git a/merge-ort.c b/merge-ort.c
index 6dbb680ede..77310a4a52 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -37,8 +37,9 @@
 #include "merge-ll.h"
 #include "match-trees.h"
 #include "mem-pool.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "path.h"
 #include "promisor-remote.h"
diff --git a/meson.build b/meson.build
index c47cb79af0..b906e78d89 100644
--- a/meson.build
+++ b/meson.build
@@ -296,6 +296,7 @@ libgit_sources = [
   'common-init.c',
   'compat/nonblock.c',
   'compat/obstack.c',
+  'compat/open.c',
   'compat/terminal.c',
   'compiler-tricks/not-constant.c',
   'config.c',
@@ -386,6 +387,7 @@ libgit_sources = [
   'object-file-convert.c',
   'object-file.c',
   'object-name.c',
+  'object-store.c',
   'object.c',
   'oid-array.c',
   'oidmap.c',
diff --git a/midx-write.c b/midx-write.c
index 48a4dc5e94..dd3b3070e5 100644
--- a/midx-write.c
+++ b/midx-write.c
@@ -1098,7 +1098,7 @@ static int write_midx_internal(struct repository *r, const char *object_dir,
 			    object_dir);
 	else
 		get_midx_filename(r->hash_algo, &midx_name, object_dir);
-	if (safe_create_leading_directories(midx_name.buf))
+	if (safe_create_leading_directories(r, midx_name.buf))
 		die_errno(_("unable to create leading directories of %s"),
 			  midx_name.buf);
 
diff --git a/midx.c b/midx.c
index 807fdf72f7..3d0015f782 100644
--- a/midx.c
+++ b/midx.c
@@ -5,7 +5,6 @@
 #include "dir.h"
 #include "hex.h"
 #include "packfile.h"
-#include "object-file.h"
 #include "hash-lookup.h"
 #include "midx.h"
 #include "progress.h"
diff --git a/notes-cache.c b/notes-cache.c
index ecfdf6e43b..150241b15e 100644
--- a/notes-cache.c
+++ b/notes-cache.c
@@ -2,7 +2,8 @@
 
 #include "git-compat-util.h"
 #include "notes-cache.h"
-#include "object-store-ll.h"
+#include "object-file.h"
+#include "object-store.h"
 #include "pretty.h"
 #include "repository.h"
 #include "commit.h"
diff --git a/notes-merge.c b/notes-merge.c
index 5008faef45..dae8e6a281 100644
--- a/notes-merge.c
+++ b/notes-merge.c
@@ -8,7 +8,7 @@
 #include "refs.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "repository.h"
 #include "diff.h"
@@ -296,7 +296,7 @@ static void check_notes_merge_worktree(struct notes_merge_options *o)
 				    "(%s exists)."), repo_git_path_replace(the_repository, &buf, "NOTES_MERGE_*"));
 		}
 
-		if (safe_create_leading_directories_const(repo_git_path_replace(the_repository, &buf,
+		if (safe_create_leading_directories_const(the_repository, repo_git_path_replace(the_repository, &buf,
 				NOTES_MERGE_WORKTREE "/.test")))
 			die_errno("unable to create directory %s",
 				  repo_git_path_replace(the_repository, &buf, NOTES_MERGE_WORKTREE));
@@ -314,7 +314,7 @@ static void write_buf_to_worktree(const struct object_id *obj,
 {
 	int fd;
 	char *path = repo_git_path(the_repository, NOTES_MERGE_WORKTREE "/%s", oid_to_hex(obj));
-	if (safe_create_leading_directories_const(path))
+	if (safe_create_leading_directories_const(the_repository, path))
 		die_errno("unable to create directory for '%s'", path);
 
 	fd = xopen(path, O_WRONLY | O_EXCL | O_CREAT, 0666);
@@ -729,7 +729,7 @@ int notes_merge_commit(struct notes_merge_options *o,
 		/* write file as blob, and add to partial_tree */
 		if (stat(path.buf, &st))
 			die_errno("Failed to stat '%s'", path.buf);
-		if (index_path(o->repo->index, &blob_oid, path.buf, &st, HASH_WRITE_OBJECT))
+		if (index_path(o->repo->index, &blob_oid, path.buf, &st, INDEX_WRITE_OBJECT))
 			die("Failed to write blob object from '%s'", path.buf);
 		if (add_note(partial_tree, &obj_oid, &blob_oid, NULL))
 			die("Failed to add resolved note '%s' to notes tree",
diff --git a/notes.c b/notes.c
index ce5a1006a8..d9645c4b5d 100644
--- a/notes.c
+++ b/notes.c
@@ -6,8 +6,9 @@
 #include "environment.h"
 #include "hex.h"
 #include "notes.h"
+#include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "utf8.h"
 #include "strbuf.h"
 #include "tree-walk.h"
diff --git a/object-file.c b/object-file.c
index f3810871f0..9cc3a24a40 100644
--- a/object-file.c
+++ b/object-file.c
@@ -11,225 +11,37 @@
 #define DISABLE_SIGN_COMPARE_WARNINGS
 
 #include "git-compat-util.h"
-#include "abspath.h"
-#include "config.h"
+#include "bulk-checkin.h"
 #include "convert.h"
+#include "dir.h"
 #include "environment.h"
+#include "fsck.h"
 #include "gettext.h"
 #include "hex.h"
-#include "string-list.h"
-#include "lockfile.h"
-#include "pack.h"
-#include "commit.h"
-#include "run-command.h"
-#include "refs.h"
-#include "bulk-checkin.h"
-#include "repository.h"
-#include "replace-object.h"
-#include "streaming.h"
-#include "dir.h"
-#include "list.h"
-#include "quote.h"
-#include "packfile.h"
+#include "loose.h"
+#include "object-file-convert.h"
 #include "object-file.h"
 #include "object-store.h"
 #include "oidtree.h"
+#include "pack.h"
+#include "packfile.h"
 #include "path.h"
-#include "promisor-remote.h"
 #include "setup.h"
-#include "submodule.h"
-#include "fsck.h"
-#include "loose.h"
-#include "object-file-convert.h"
+#include "streaming.h"
 
 /* The maximum size for an object header. */
 #define MAX_HEADER_LEN 32
 
-/*
- * This is meant to hold a *small* number of objects that you would
- * want repo_read_object_file() to be able to return, but yet you do not want
- * to write them into the object store (e.g. a browse-only
- * application).
- */
-static struct cached_object_entry {
-	struct object_id oid;
-	struct cached_object {
-		enum object_type type;
-		const void *buf;
-		unsigned long size;
-	} value;
-} *cached_objects;
-static int cached_object_nr, cached_object_alloc;
-
-static const struct cached_object *find_cached_object(const struct object_id *oid)
-{
-	static const struct cached_object empty_tree = {
-		.type = OBJ_TREE,
-		.buf = "",
-	};
-	int i;
-	const struct cached_object_entry *co = cached_objects;
-
-	for (i = 0; i < cached_object_nr; i++, co++) {
-		if (oideq(&co->oid, oid))
-			return &co->value;
-	}
-	if (oideq(oid, the_hash_algo->empty_tree))
-		return &empty_tree;
-	return NULL;
-}
-
-
 static int get_conv_flags(unsigned flags)
 {
-	if (flags & HASH_RENORMALIZE)
+	if (flags & INDEX_RENORMALIZE)
 		return CONV_EOL_RENORMALIZE;
-	else if (flags & HASH_WRITE_OBJECT)
+	else if (flags & INDEX_WRITE_OBJECT)
 		return global_conv_flags_eol | CONV_WRITE_OBJECT;
 	else
 		return 0;
 }
 
-
-int mkdir_in_gitdir(const char *path)
-{
-	if (mkdir(path, 0777)) {
-		int saved_errno = errno;
-		struct stat st;
-		struct strbuf sb = STRBUF_INIT;
-
-		if (errno != EEXIST)
-			return -1;
-		/*
-		 * Are we looking at a path in a symlinked worktree
-		 * whose original repository does not yet have it?
-		 * e.g. .git/rr-cache pointing at its original
-		 * repository in which the user hasn't performed any
-		 * conflict resolution yet?
-		 */
-		if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
-		    strbuf_readlink(&sb, path, st.st_size) ||
-		    !is_absolute_path(sb.buf) ||
-		    mkdir(sb.buf, 0777)) {
-			strbuf_release(&sb);
-			errno = saved_errno;
-			return -1;
-		}
-		strbuf_release(&sb);
-	}
-	return adjust_shared_perm(the_repository, path);
-}
-
-static enum scld_error safe_create_leading_directories_1(char *path, int share)
-{
-	char *next_component = path + offset_1st_component(path);
-	enum scld_error ret = SCLD_OK;
-
-	while (ret == SCLD_OK && next_component) {
-		struct stat st;
-		char *slash = next_component, slash_character;
-
-		while (*slash && !is_dir_sep(*slash))
-			slash++;
-
-		if (!*slash)
-			break;
-
-		next_component = slash + 1;
-		while (is_dir_sep(*next_component))
-			next_component++;
-		if (!*next_component)
-			break;
-
-		slash_character = *slash;
-		*slash = '\0';
-		if (!stat(path, &st)) {
-			/* path exists */
-			if (!S_ISDIR(st.st_mode)) {
-				errno = ENOTDIR;
-				ret = SCLD_EXISTS;
-			}
-		} else if (mkdir(path, 0777)) {
-			if (errno == EEXIST &&
-			    !stat(path, &st) && S_ISDIR(st.st_mode))
-				; /* somebody created it since we checked */
-			else if (errno == ENOENT)
-				/*
-				 * Either mkdir() failed because
-				 * somebody just pruned the containing
-				 * directory, or stat() failed because
-				 * the file that was in our way was
-				 * just removed.  Either way, inform
-				 * the caller that it might be worth
-				 * trying again:
-				 */
-				ret = SCLD_VANISHED;
-			else
-				ret = SCLD_FAILED;
-		} else if (share && adjust_shared_perm(the_repository, path)) {
-			ret = SCLD_PERMS;
-		}
-		*slash = slash_character;
-	}
-	return ret;
-}
-
-enum scld_error safe_create_leading_directories(char *path)
-{
-	return safe_create_leading_directories_1(path, 1);
-}
-
-enum scld_error safe_create_leading_directories_no_share(char *path)
-{
-	return safe_create_leading_directories_1(path, 0);
-}
-
-enum scld_error safe_create_leading_directories_const(const char *path)
-{
-	int save_errno;
-	/* path points to cache entries, so xstrdup before messing with it */
-	char *buf = xstrdup(path);
-	enum scld_error result = safe_create_leading_directories(buf);
-
-	save_errno = errno;
-	free(buf);
-	errno = save_errno;
-	return result;
-}
-
-int odb_mkstemp(struct strbuf *temp_filename, const char *pattern)
-{
-	int fd;
-	/*
-	 * we let the umask do its job, don't try to be more
-	 * restrictive except to remove write permission.
-	 */
-	int mode = 0444;
-	repo_git_path_replace(the_repository, temp_filename, "objects/%s", pattern);
-	fd = git_mkstemp_mode(temp_filename->buf, mode);
-	if (0 <= fd)
-		return fd;
-
-	/* slow path */
-	/* some mkstemp implementations erase temp_filename on failure */
-	repo_git_path_replace(the_repository, temp_filename, "objects/%s", pattern);
-	safe_create_leading_directories(temp_filename->buf);
-	return xmkstemp_mode(temp_filename->buf, mode);
-}
-
-int odb_pack_keep(const char *name)
-{
-	int fd;
-
-	fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
-	if (0 <= fd)
-		return fd;
-
-	/* slow path */
-	safe_create_leading_directories_const(name);
-	return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
-}
-
 static void fill_loose_path(struct strbuf *buf, const struct object_id *oid)
 {
 	int i;
@@ -243,9 +55,9 @@ static void fill_loose_path(struct strbuf *buf, const struct object_id *oid)
 	}
 }
 
-static const char *odb_loose_path(struct object_directory *odb,
-				  struct strbuf *buf,
-				  const struct object_id *oid)
+const char *odb_loose_path(struct object_directory *odb,
+			   struct strbuf *buf,
+			   const struct object_id *oid)
 {
 	strbuf_reset(buf);
 	strbuf_addstr(buf, odb->path);
@@ -254,513 +66,6 @@ static const char *odb_loose_path(struct object_directory *odb,
 	return buf->buf;
 }
 
-const char *loose_object_path(struct repository *r, struct strbuf *buf,
-			      const struct object_id *oid)
-{
-	return odb_loose_path(r->objects->odb, buf, oid);
-}
-
-/*
- * Return non-zero iff the path is usable as an alternate object database.
- */
-static int alt_odb_usable(struct raw_object_store *o,
-			  struct strbuf *path,
-			  const char *normalized_objdir, khiter_t *pos)
-{
-	int r;
-
-	/* Detect cases where alternate disappeared */
-	if (!is_directory(path->buf)) {
-		error(_("object directory %s does not exist; "
-			"check .git/objects/info/alternates"),
-		      path->buf);
-		return 0;
-	}
-
-	/*
-	 * Prevent the common mistake of listing the same
-	 * thing twice, or object directory itself.
-	 */
-	if (!o->odb_by_path) {
-		khiter_t p;
-
-		o->odb_by_path = kh_init_odb_path_map();
-		assert(!o->odb->next);
-		p = kh_put_odb_path_map(o->odb_by_path, o->odb->path, &r);
-		assert(r == 1); /* never used */
-		kh_value(o->odb_by_path, p) = o->odb;
-	}
-	if (fspatheq(path->buf, normalized_objdir))
-		return 0;
-	*pos = kh_put_odb_path_map(o->odb_by_path, path->buf, &r);
-	/* r: 0 = exists, 1 = never used, 2 = deleted */
-	return r == 0 ? 0 : 1;
-}
-
-/*
- * Prepare alternate object database registry.
- *
- * The variable alt_odb_list points at the list of struct
- * object_directory.  The elements on this list come from
- * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
- * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
- * whose contents is similar to that environment variable but can be
- * LF separated.  Its base points at a statically allocated buffer that
- * contains "/the/directory/corresponding/to/.git/objects/...", while
- * its name points just after the slash at the end of ".git/objects/"
- * in the example above, and has enough space to hold all hex characters
- * of the object ID, an extra slash for the first level indirection, and
- * the terminating NUL.
- */
-static void read_info_alternates(struct repository *r,
-				 const char *relative_base,
-				 int depth);
-static int link_alt_odb_entry(struct repository *r, const struct strbuf *entry,
-	const char *relative_base, int depth, const char *normalized_objdir)
-{
-	struct object_directory *ent;
-	struct strbuf pathbuf = STRBUF_INIT;
-	struct strbuf tmp = STRBUF_INIT;
-	khiter_t pos;
-	int ret = -1;
-
-	if (!is_absolute_path(entry->buf) && relative_base) {
-		strbuf_realpath(&pathbuf, relative_base, 1);
-		strbuf_addch(&pathbuf, '/');
-	}
-	strbuf_addbuf(&pathbuf, entry);
-
-	if (!strbuf_realpath(&tmp, pathbuf.buf, 0)) {
-		error(_("unable to normalize alternate object path: %s"),
-		      pathbuf.buf);
-		goto error;
-	}
-	strbuf_swap(&pathbuf, &tmp);
-
-	/*
-	 * The trailing slash after the directory name is given by
-	 * this function at the end. Remove duplicates.
-	 */
-	while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
-		strbuf_setlen(&pathbuf, pathbuf.len - 1);
-
-	if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir, &pos))
-		goto error;
-
-	CALLOC_ARRAY(ent, 1);
-	/* pathbuf.buf is already in r->objects->odb_by_path */
-	ent->path = strbuf_detach(&pathbuf, NULL);
-
-	/* add the alternate entry */
-	*r->objects->odb_tail = ent;
-	r->objects->odb_tail = &(ent->next);
-	ent->next = NULL;
-	assert(r->objects->odb_by_path);
-	kh_value(r->objects->odb_by_path, pos) = ent;
-
-	/* recursively add alternates */
-	read_info_alternates(r, ent->path, depth + 1);
-	ret = 0;
- error:
-	strbuf_release(&tmp);
-	strbuf_release(&pathbuf);
-	return ret;
-}
-
-static const char *parse_alt_odb_entry(const char *string,
-				       int sep,
-				       struct strbuf *out)
-{
-	const char *end;
-
-	strbuf_reset(out);
-
-	if (*string == '#') {
-		/* comment; consume up to next separator */
-		end = strchrnul(string, sep);
-	} else if (*string == '"' && !unquote_c_style(out, string, &end)) {
-		/*
-		 * quoted path; unquote_c_style has copied the
-		 * data for us and set "end". Broken quoting (e.g.,
-		 * an entry that doesn't end with a quote) falls
-		 * back to the unquoted case below.
-		 */
-	} else {
-		/* normal, unquoted path */
-		end = strchrnul(string, sep);
-		strbuf_add(out, string, end - string);
-	}
-
-	if (*end)
-		end++;
-	return end;
-}
-
-static void link_alt_odb_entries(struct repository *r, const char *alt,
-				 int sep, const char *relative_base, int depth)
-{
-	struct strbuf objdirbuf = STRBUF_INIT;
-	struct strbuf entry = STRBUF_INIT;
-
-	if (!alt || !*alt)
-		return;
-
-	if (depth > 5) {
-		error(_("%s: ignoring alternate object stores, nesting too deep"),
-				relative_base);
-		return;
-	}
-
-	strbuf_realpath(&objdirbuf, r->objects->odb->path, 1);
-
-	while (*alt) {
-		alt = parse_alt_odb_entry(alt, sep, &entry);
-		if (!entry.len)
-			continue;
-		link_alt_odb_entry(r, &entry,
-				   relative_base, depth, objdirbuf.buf);
-	}
-	strbuf_release(&entry);
-	strbuf_release(&objdirbuf);
-}
-
-static void read_info_alternates(struct repository *r,
-				 const char *relative_base,
-				 int depth)
-{
-	char *path;
-	struct strbuf buf = STRBUF_INIT;
-
-	path = xstrfmt("%s/info/alternates", relative_base);
-	if (strbuf_read_file(&buf, path, 1024) < 0) {
-		warn_on_fopen_errors(path);
-		free(path);
-		return;
-	}
-
-	link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
-	strbuf_release(&buf);
-	free(path);
-}
-
-void add_to_alternates_file(const char *reference)
-{
-	struct lock_file lock = LOCK_INIT;
-	char *alts = repo_git_path(the_repository, "objects/info/alternates");
-	FILE *in, *out;
-	int found = 0;
-
-	hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
-	out = fdopen_lock_file(&lock, "w");
-	if (!out)
-		die_errno(_("unable to fdopen alternates lockfile"));
-
-	in = fopen(alts, "r");
-	if (in) {
-		struct strbuf line = STRBUF_INIT;
-
-		while (strbuf_getline(&line, in) != EOF) {
-			if (!strcmp(reference, line.buf)) {
-				found = 1;
-				break;
-			}
-			fprintf_or_die(out, "%s\n", line.buf);
-		}
-
-		strbuf_release(&line);
-		fclose(in);
-	}
-	else if (errno != ENOENT)
-		die_errno(_("unable to read alternates file"));
-
-	if (found) {
-		rollback_lock_file(&lock);
-	} else {
-		fprintf_or_die(out, "%s\n", reference);
-		if (commit_lock_file(&lock))
-			die_errno(_("unable to move new alternates file into place"));
-		if (the_repository->objects->loaded_alternates)
-			link_alt_odb_entries(the_repository, reference,
-					     '\n', NULL, 0);
-	}
-	free(alts);
-}
-
-void add_to_alternates_memory(const char *reference)
-{
-	/*
-	 * Make sure alternates are initialized, or else our entry may be
-	 * overwritten when they are.
-	 */
-	prepare_alt_odb(the_repository);
-
-	link_alt_odb_entries(the_repository, reference,
-			     '\n', NULL, 0);
-}
-
-struct object_directory *set_temporary_primary_odb(const char *dir, int will_destroy)
-{
-	struct object_directory *new_odb;
-
-	/*
-	 * Make sure alternates are initialized, or else our entry may be
-	 * overwritten when they are.
-	 */
-	prepare_alt_odb(the_repository);
-
-	/*
-	 * Make a new primary odb and link the old primary ODB in as an
-	 * alternate
-	 */
-	new_odb = xcalloc(1, sizeof(*new_odb));
-	new_odb->path = xstrdup(dir);
-
-	/*
-	 * Disable ref updates while a temporary odb is active, since
-	 * the objects in the database may roll back.
-	 */
-	new_odb->disable_ref_updates = 1;
-	new_odb->will_destroy = will_destroy;
-	new_odb->next = the_repository->objects->odb;
-	the_repository->objects->odb = new_odb;
-	return new_odb->next;
-}
-
-void restore_primary_odb(struct object_directory *restore_odb, const char *old_path)
-{
-	struct object_directory *cur_odb = the_repository->objects->odb;
-
-	if (strcmp(old_path, cur_odb->path))
-		BUG("expected %s as primary object store; found %s",
-		    old_path, cur_odb->path);
-
-	if (cur_odb->next != restore_odb)
-		BUG("we expect the old primary object store to be the first alternate");
-
-	the_repository->objects->odb = restore_odb;
-	free_object_directory(cur_odb);
-}
-
-/*
- * Compute the exact path an alternate is at and returns it. In case of
- * error NULL is returned and the human readable error is added to `err`
- * `path` may be relative and should point to $GIT_DIR.
- * `err` must not be null.
- */
-char *compute_alternate_path(const char *path, struct strbuf *err)
-{
-	char *ref_git = NULL;
-	const char *repo;
-	int seen_error = 0;
-
-	ref_git = real_pathdup(path, 0);
-	if (!ref_git) {
-		seen_error = 1;
-		strbuf_addf(err, _("path '%s' does not exist"), path);
-		goto out;
-	}
-
-	repo = read_gitfile(ref_git);
-	if (!repo)
-		repo = read_gitfile(mkpath("%s/.git", ref_git));
-	if (repo) {
-		free(ref_git);
-		ref_git = xstrdup(repo);
-	}
-
-	if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
-		char *ref_git_git = mkpathdup("%s/.git", ref_git);
-		free(ref_git);
-		ref_git = ref_git_git;
-	} else if (!is_directory(mkpath("%s/objects", ref_git))) {
-		struct strbuf sb = STRBUF_INIT;
-		seen_error = 1;
-		if (get_common_dir(&sb, ref_git)) {
-			strbuf_addf(err,
-				    _("reference repository '%s' as a linked "
-				      "checkout is not supported yet."),
-				    path);
-			goto out;
-		}
-
-		strbuf_addf(err, _("reference repository '%s' is not a "
-					"local repository."), path);
-		goto out;
-	}
-
-	if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
-		strbuf_addf(err, _("reference repository '%s' is shallow"),
-			    path);
-		seen_error = 1;
-		goto out;
-	}
-
-	if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
-		strbuf_addf(err,
-			    _("reference repository '%s' is grafted"),
-			    path);
-		seen_error = 1;
-		goto out;
-	}
-
-out:
-	if (seen_error) {
-		FREE_AND_NULL(ref_git);
-	}
-
-	return ref_git;
-}
-
-struct object_directory *find_odb(struct repository *r, const char *obj_dir)
-{
-	struct object_directory *odb;
-	char *obj_dir_real = real_pathdup(obj_dir, 1);
-	struct strbuf odb_path_real = STRBUF_INIT;
-
-	prepare_alt_odb(r);
-	for (odb = r->objects->odb; odb; odb = odb->next) {
-		strbuf_realpath(&odb_path_real, odb->path, 1);
-		if (!strcmp(obj_dir_real, odb_path_real.buf))
-			break;
-	}
-
-	free(obj_dir_real);
-	strbuf_release(&odb_path_real);
-
-	if (!odb)
-		die(_("could not find object directory matching %s"), obj_dir);
-	return odb;
-}
-
-static void fill_alternate_refs_command(struct child_process *cmd,
-					const char *repo_path)
-{
-	const char *value;
-
-	if (!git_config_get_value("core.alternateRefsCommand", &value)) {
-		cmd->use_shell = 1;
-
-		strvec_push(&cmd->args, value);
-		strvec_push(&cmd->args, repo_path);
-	} else {
-		cmd->git_cmd = 1;
-
-		strvec_pushf(&cmd->args, "--git-dir=%s", repo_path);
-		strvec_push(&cmd->args, "for-each-ref");
-		strvec_push(&cmd->args, "--format=%(objectname)");
-
-		if (!git_config_get_value("core.alternateRefsPrefixes", &value)) {
-			strvec_push(&cmd->args, "--");
-			strvec_split(&cmd->args, value);
-		}
-	}
-
-	strvec_pushv(&cmd->env, (const char **)local_repo_env);
-	cmd->out = -1;
-}
-
-static void read_alternate_refs(const char *path,
-				alternate_ref_fn *cb,
-				void *data)
-{
-	struct child_process cmd = CHILD_PROCESS_INIT;
-	struct strbuf line = STRBUF_INIT;
-	FILE *fh;
-
-	fill_alternate_refs_command(&cmd, path);
-
-	if (start_command(&cmd))
-		return;
-
-	fh = xfdopen(cmd.out, "r");
-	while (strbuf_getline_lf(&line, fh) != EOF) {
-		struct object_id oid;
-		const char *p;
-
-		if (parse_oid_hex(line.buf, &oid, &p) || *p) {
-			warning(_("invalid line while parsing alternate refs: %s"),
-				line.buf);
-			break;
-		}
-
-		cb(&oid, data);
-	}
-
-	fclose(fh);
-	finish_command(&cmd);
-	strbuf_release(&line);
-}
-
-struct alternate_refs_data {
-	alternate_ref_fn *fn;
-	void *data;
-};
-
-static int refs_from_alternate_cb(struct object_directory *e,
-				  void *data)
-{
-	struct strbuf path = STRBUF_INIT;
-	size_t base_len;
-	struct alternate_refs_data *cb = data;
-
-	if (!strbuf_realpath(&path, e->path, 0))
-		goto out;
-	if (!strbuf_strip_suffix(&path, "/objects"))
-		goto out;
-	base_len = path.len;
-
-	/* Is this a git repository with refs? */
-	strbuf_addstr(&path, "/refs");
-	if (!is_directory(path.buf))
-		goto out;
-	strbuf_setlen(&path, base_len);
-
-	read_alternate_refs(path.buf, cb->fn, cb->data);
-
-out:
-	strbuf_release(&path);
-	return 0;
-}
-
-void for_each_alternate_ref(alternate_ref_fn fn, void *data)
-{
-	struct alternate_refs_data cb;
-	cb.fn = fn;
-	cb.data = data;
-	foreach_alt_odb(refs_from_alternate_cb, &cb);
-}
-
-int foreach_alt_odb(alt_odb_fn fn, void *cb)
-{
-	struct object_directory *ent;
-	int r = 0;
-
-	prepare_alt_odb(the_repository);
-	for (ent = the_repository->objects->odb->next; ent; ent = ent->next) {
-		r = fn(ent, cb);
-		if (r)
-			break;
-	}
-	return r;
-}
-
-void prepare_alt_odb(struct repository *r)
-{
-	if (r->objects->loaded_alternates)
-		return;
-
-	link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
-
-	read_info_alternates(r, r->objects->odb->path, 0);
-	r->objects->loaded_alternates = 1;
-}
-
-int has_alt_odb(struct repository *r)
-{
-	prepare_alt_odb(r);
-	return !!r->objects->odb->next;
-}
-
 /* Returns 1 if we have successfully freshened the file, 0 otherwise. */
 static int freshen_file(const char *fn)
 {
@@ -825,54 +130,6 @@ int has_loose_object(const struct object_id *oid)
 	return check_and_freshen(oid, 0);
 }
 
-static void mmap_limit_check(size_t length)
-{
-	static size_t limit = 0;
-	if (!limit) {
-		limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
-		if (!limit)
-			limit = SIZE_MAX;
-	}
-	if (length > limit)
-		die(_("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX),
-		    (uintmax_t)length, (uintmax_t)limit);
-}
-
-void *xmmap_gently(void *start, size_t length,
-		  int prot, int flags, int fd, off_t offset)
-{
-	void *ret;
-
-	mmap_limit_check(length);
-	ret = mmap(start, length, prot, flags, fd, offset);
-	if (ret == MAP_FAILED && !length)
-		ret = NULL;
-	return ret;
-}
-
-const char *mmap_os_err(void)
-{
-	static const char blank[] = "";
-#if defined(__linux__)
-	if (errno == ENOMEM) {
-		/* this continues an existing error message: */
-		static const char enomem[] =
-", check sys.vm.max_map_count and/or RLIMIT_DATA";
-		return enomem;
-	}
-#endif /* OS-specific bits */
-	return blank;
-}
-
-void *xmmap(void *start, size_t length,
-	int prot, int flags, int fd, off_t offset)
-{
-	void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
-	if (ret == MAP_FAILED)
-		die_errno(_("mmap failed%s"), mmap_os_err());
-	return ret;
-}
-
 static int format_object_header_literally(char *str, size_t size,
 					  const char *type, size_t objsize)
 {
@@ -940,33 +197,6 @@ int stream_object_signature(struct repository *r, const struct object_id *oid)
 	return !oideq(oid, &real_oid) ? -1 : 0;
 }
 
-int git_open_cloexec(const char *name, int flags)
-{
-	int fd;
-	static int o_cloexec = O_CLOEXEC;
-
-	fd = open(name, flags | o_cloexec);
-	if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
-		/* Try again w/o O_CLOEXEC: the kernel might not support it */
-		o_cloexec &= ~O_CLOEXEC;
-		fd = open(name, flags | o_cloexec);
-	}
-
-#if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
-	{
-		static int fd_cloexec = FD_CLOEXEC;
-
-		if (!o_cloexec && 0 <= fd && fd_cloexec) {
-			/* Opened w/o O_CLOEXEC?  try with fcntl(2) to add it */
-			int flags = fcntl(fd, F_GETFD);
-			if (fcntl(fd, F_SETFD, flags | fd_cloexec))
-				fd_cloexec = 0;
-		}
-	}
-#endif
-	return fd;
-}
-
 /*
  * Find "oid" as a loose object in the local repository or in an alternate.
  * Returns 0 on success, negative on failure.
@@ -1235,9 +465,9 @@ int parse_loose_header(const char *hdr, struct object_info *oi)
 	return 0;
 }
 
-static int loose_object_info(struct repository *r,
-			     const struct object_id *oid,
-			     struct object_info *oi, int flags)
+int loose_object_info(struct repository *r,
+		      const struct object_id *oid,
+		      struct object_info *oi, int flags)
 {
 	int status = 0;
 	int fd;
@@ -1335,345 +565,6 @@ cleanup:
 	return status;
 }
 
-int obj_read_use_lock = 0;
-pthread_mutex_t obj_read_mutex;
-
-void enable_obj_read_lock(void)
-{
-	if (obj_read_use_lock)
-		return;
-
-	obj_read_use_lock = 1;
-	init_recursive_mutex(&obj_read_mutex);
-}
-
-void disable_obj_read_lock(void)
-{
-	if (!obj_read_use_lock)
-		return;
-
-	obj_read_use_lock = 0;
-	pthread_mutex_destroy(&obj_read_mutex);
-}
-
-int fetch_if_missing = 1;
-
-static int do_oid_object_info_extended(struct repository *r,
-				       const struct object_id *oid,
-				       struct object_info *oi, unsigned flags)
-{
-	static struct object_info blank_oi = OBJECT_INFO_INIT;
-	const struct cached_object *co;
-	struct pack_entry e;
-	int rtype;
-	const struct object_id *real = oid;
-	int already_retried = 0;
-
-
-	if (flags & OBJECT_INFO_LOOKUP_REPLACE)
-		real = lookup_replace_object(r, oid);
-
-	if (is_null_oid(real))
-		return -1;
-
-	if (!oi)
-		oi = &blank_oi;
-
-	co = find_cached_object(real);
-	if (co) {
-		if (oi->typep)
-			*(oi->typep) = co->type;
-		if (oi->sizep)
-			*(oi->sizep) = co->size;
-		if (oi->disk_sizep)
-			*(oi->disk_sizep) = 0;
-		if (oi->delta_base_oid)
-			oidclr(oi->delta_base_oid, the_repository->hash_algo);
-		if (oi->type_name)
-			strbuf_addstr(oi->type_name, type_name(co->type));
-		if (oi->contentp)
-			*oi->contentp = xmemdupz(co->buf, co->size);
-		oi->whence = OI_CACHED;
-		return 0;
-	}
-
-	while (1) {
-		if (find_pack_entry(r, real, &e))
-			break;
-
-		/* Most likely it's a loose object. */
-		if (!loose_object_info(r, real, oi, flags))
-			return 0;
-
-		/* Not a loose object; someone else may have just packed it. */
-		if (!(flags & OBJECT_INFO_QUICK)) {
-			reprepare_packed_git(r);
-			if (find_pack_entry(r, real, &e))
-				break;
-		}
-
-		/*
-		 * If r is the_repository, this might be an attempt at
-		 * accessing a submodule object as if it were in the_repository
-		 * (having called add_submodule_odb() on that submodule's ODB).
-		 * If any such ODBs exist, register them and try again.
-		 */
-		if (r == the_repository &&
-		    register_all_submodule_odb_as_alternates())
-			/* We added some alternates; retry */
-			continue;
-
-		/* Check if it is a missing object */
-		if (fetch_if_missing && repo_has_promisor_remote(r) &&
-		    !already_retried &&
-		    !(flags & OBJECT_INFO_SKIP_FETCH_OBJECT)) {
-			promisor_remote_get_direct(r, real, 1);
-			already_retried = 1;
-			continue;
-		}
-
-		if (flags & OBJECT_INFO_DIE_IF_CORRUPT) {
-			const struct packed_git *p;
-			if ((flags & OBJECT_INFO_LOOKUP_REPLACE) && !oideq(real, oid))
-				die(_("replacement %s not found for %s"),
-				    oid_to_hex(real), oid_to_hex(oid));
-			if ((p = has_packed_and_bad(r, real)))
-				die(_("packed object %s (stored in %s) is corrupt"),
-				    oid_to_hex(real), p->pack_name);
-		}
-		return -1;
-	}
-
-	if (oi == &blank_oi)
-		/*
-		 * We know that the caller doesn't actually need the
-		 * information below, so return early.
-		 */
-		return 0;
-	rtype = packed_object_info(r, e.p, e.offset, oi);
-	if (rtype < 0) {
-		mark_bad_packed_object(e.p, real);
-		return do_oid_object_info_extended(r, real, oi, 0);
-	} else if (oi->whence == OI_PACKED) {
-		oi->u.packed.offset = e.offset;
-		oi->u.packed.pack = e.p;
-		oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
-					 rtype == OBJ_OFS_DELTA);
-	}
-
-	return 0;
-}
-
-static int oid_object_info_convert(struct repository *r,
-				   const struct object_id *input_oid,
-				   struct object_info *input_oi, unsigned flags)
-{
-	const struct git_hash_algo *input_algo = &hash_algos[input_oid->algo];
-	int do_die = flags & OBJECT_INFO_DIE_IF_CORRUPT;
-	struct strbuf type_name = STRBUF_INIT;
-	struct object_id oid, delta_base_oid;
-	struct object_info new_oi, *oi;
-	unsigned long size;
-	void *content;
-	int ret;
-
-	if (repo_oid_to_algop(r, input_oid, the_hash_algo, &oid)) {
-		if (do_die)
-			die(_("missing mapping of %s to %s"),
-			    oid_to_hex(input_oid), the_hash_algo->name);
-		return -1;
-	}
-
-	/* Is new_oi needed? */
-	oi = input_oi;
-	if (input_oi && (input_oi->delta_base_oid || input_oi->sizep ||
-			 input_oi->contentp)) {
-		new_oi = *input_oi;
-		/* Does delta_base_oid need to be converted? */
-		if (input_oi->delta_base_oid)
-			new_oi.delta_base_oid = &delta_base_oid;
-		/* Will the attributes differ when converted? */
-		if (input_oi->sizep || input_oi->contentp) {
-			new_oi.contentp = &content;
-			new_oi.sizep = &size;
-			new_oi.type_name = &type_name;
-		}
-		oi = &new_oi;
-	}
-
-	ret = oid_object_info_extended(r, &oid, oi, flags);
-	if (ret)
-		return -1;
-	if (oi == input_oi)
-		return ret;
-
-	if (new_oi.contentp) {
-		struct strbuf outbuf = STRBUF_INIT;
-		enum object_type type;
-
-		type = type_from_string_gently(type_name.buf, type_name.len,
-					       !do_die);
-		if (type == -1)
-			return -1;
-		if (type != OBJ_BLOB) {
-			ret = convert_object_file(the_repository, &outbuf,
-						  the_hash_algo, input_algo,
-						  content, size, type, !do_die);
-			free(content);
-			if (ret == -1)
-				return -1;
-			size = outbuf.len;
-			content = strbuf_detach(&outbuf, NULL);
-		}
-		if (input_oi->sizep)
-			*input_oi->sizep = size;
-		if (input_oi->contentp)
-			*input_oi->contentp = content;
-		else
-			free(content);
-		if (input_oi->type_name)
-			*input_oi->type_name = type_name;
-		else
-			strbuf_release(&type_name);
-	}
-	if (new_oi.delta_base_oid == &delta_base_oid) {
-		if (repo_oid_to_algop(r, &delta_base_oid, input_algo,
-				 input_oi->delta_base_oid)) {
-			if (do_die)
-				die(_("missing mapping of %s to %s"),
-				    oid_to_hex(&delta_base_oid),
-				    input_algo->name);
-			return -1;
-		}
-	}
-	input_oi->whence = new_oi.whence;
-	input_oi->u = new_oi.u;
-	return ret;
-}
-
-int oid_object_info_extended(struct repository *r, const struct object_id *oid,
-			     struct object_info *oi, unsigned flags)
-{
-	int ret;
-
-	if (oid->algo && (hash_algo_by_ptr(r->hash_algo) != oid->algo))
-		return oid_object_info_convert(r, oid, oi, flags);
-
-	obj_read_lock();
-	ret = do_oid_object_info_extended(r, oid, oi, flags);
-	obj_read_unlock();
-	return ret;
-}
-
-
-/* returns enum object_type or negative */
-int oid_object_info(struct repository *r,
-		    const struct object_id *oid,
-		    unsigned long *sizep)
-{
-	enum object_type type;
-	struct object_info oi = OBJECT_INFO_INIT;
-
-	oi.typep = &type;
-	oi.sizep = sizep;
-	if (oid_object_info_extended(r, oid, &oi,
-				      OBJECT_INFO_LOOKUP_REPLACE) < 0)
-		return -1;
-	return type;
-}
-
-int pretend_object_file(void *buf, unsigned long len, enum object_type type,
-			struct object_id *oid)
-{
-	struct cached_object_entry *co;
-	char *co_buf;
-
-	hash_object_file(the_hash_algo, buf, len, type, oid);
-	if (repo_has_object_file_with_flags(the_repository, oid, OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT) ||
-	    find_cached_object(oid))
-		return 0;
-	ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
-	co = &cached_objects[cached_object_nr++];
-	co->value.size = len;
-	co->value.type = type;
-	co_buf = xmalloc(len);
-	memcpy(co_buf, buf, len);
-	co->value.buf = co_buf;
-	oidcpy(&co->oid, oid);
-	return 0;
-}
-
-/*
- * This function dies on corrupt objects; the callers who want to
- * deal with them should arrange to call oid_object_info_extended() and give
- * error messages themselves.
- */
-void *repo_read_object_file(struct repository *r,
-			    const struct object_id *oid,
-			    enum object_type *type,
-			    unsigned long *size)
-{
-	struct object_info oi = OBJECT_INFO_INIT;
-	unsigned flags = OBJECT_INFO_DIE_IF_CORRUPT | OBJECT_INFO_LOOKUP_REPLACE;
-	void *data;
-
-	oi.typep = type;
-	oi.sizep = size;
-	oi.contentp = &data;
-	if (oid_object_info_extended(r, oid, &oi, flags))
-		return NULL;
-
-	return data;
-}
-
-void *read_object_with_reference(struct repository *r,
-				 const struct object_id *oid,
-				 enum object_type required_type,
-				 unsigned long *size,
-				 struct object_id *actual_oid_return)
-{
-	enum object_type type;
-	void *buffer;
-	unsigned long isize;
-	struct object_id actual_oid;
-
-	oidcpy(&actual_oid, oid);
-	while (1) {
-		int ref_length = -1;
-		const char *ref_type = NULL;
-
-		buffer = repo_read_object_file(r, &actual_oid, &type, &isize);
-		if (!buffer)
-			return NULL;
-		if (type == required_type) {
-			*size = isize;
-			if (actual_oid_return)
-				oidcpy(actual_oid_return, &actual_oid);
-			return buffer;
-		}
-		/* Handle references */
-		else if (type == OBJ_COMMIT)
-			ref_type = "tree ";
-		else if (type == OBJ_TAG)
-			ref_type = "object ";
-		else {
-			free(buffer);
-			return NULL;
-		}
-		ref_length = strlen(ref_type);
-
-		if (ref_length + the_hash_algo->hexsz > isize ||
-		    memcmp(buffer, ref_type, ref_length) ||
-		    get_oid_hex((char *) buffer + ref_length, &actual_oid)) {
-			free(buffer);
-			return NULL;
-		}
-		free(buffer);
-		/* Now we have the ID of the referred-to object in
-		 * actual_oid.  Check again. */
-	}
-}
-
 static void hash_object_body(const struct git_hash_algo *algo, struct git_hash_ctx *c,
 			     const void *buf, unsigned long len,
 			     struct object_id *oid,
@@ -1945,7 +836,7 @@ static int start_loose_object_common(struct strbuf *tmp_file,
 
 	fd = create_tmpfile(tmp_file, filename);
 	if (fd < 0) {
-		if (flags & HASH_SILENT)
+		if (flags & WRITE_OBJECT_FILE_SILENT)
 			return -1;
 		else if (errno == EACCES)
 			return error(_("insufficient permission for adding "
@@ -2077,7 +968,7 @@ static int write_loose_object(const struct object_id *oid, char *hdr,
 		utb.actime = mtime;
 		utb.modtime = mtime;
 		if (utime(tmp_file.buf, &utb) < 0 &&
-		    !(flags & HASH_SILENT))
+		    !(flags & WRITE_OBJECT_FILE_SILENT))
 			warning_errno(_("failed utime() on %s"), tmp_file.buf);
 	}
 
@@ -2196,7 +1087,8 @@ int stream_loose_object(struct input_stream *in_stream, size_t len,
 		struct strbuf dir = STRBUF_INIT;
 		strbuf_add(&dir, filename.buf, dirlen);
 
-		if (mkdir_in_gitdir(dir.buf) && errno != EEXIST) {
+		if (safe_create_dir_in_gitdir(the_repository, dir.buf) &&
+		    errno != EEXIST) {
 			err = error_errno(_("unable to create directory %s"), dir.buf);
 			strbuf_release(&dir);
 			goto cleanup;
@@ -2288,7 +1180,7 @@ int write_object_file_literally(const void *buf, unsigned long len,
 	write_object_file_prepare_literally(the_hash_algo, buf, len, type,
 					    oid, header, &hdrlen);
 
-	if (!(flags & HASH_WRITE_OBJECT))
+	if (!(flags & WRITE_OBJECT_FILE_PERSIST))
 		goto cleanup;
 	if (freshen_packed_object(oid) || freshen_loose_object(oid))
 		goto cleanup;
@@ -2335,32 +1227,6 @@ int force_object_loose(const struct object_id *oid, time_t mtime)
 	return ret;
 }
 
-int has_object(struct repository *r, const struct object_id *oid,
-	       unsigned flags)
-{
-	int quick = !(flags & HAS_OBJECT_RECHECK_PACKED);
-	unsigned object_info_flags = OBJECT_INFO_SKIP_FETCH_OBJECT |
-		(quick ? OBJECT_INFO_QUICK : 0);
-
-	if (!startup_info->have_repository)
-		return 0;
-	return oid_object_info_extended(r, oid, NULL, object_info_flags) >= 0;
-}
-
-int repo_has_object_file_with_flags(struct repository *r,
-				    const struct object_id *oid, int flags)
-{
-	if (!startup_info->have_repository)
-		return 0;
-	return oid_object_info_extended(r, oid, NULL, flags) >= 0;
-}
-
-int repo_has_object_file(struct repository *r,
-			 const struct object_id *oid)
-{
-	return repo_has_object_file_with_flags(r, oid, 0);
-}
-
 /*
  * We can't use the normal fsck_error_function() for index_mem(),
  * because we don't yet have a valid oid for it to report. Instead,
@@ -2385,7 +1251,7 @@ static int index_mem(struct index_state *istate,
 {
 	struct strbuf nbuf = STRBUF_INIT;
 	int ret = 0;
-	int write_object = flags & HASH_WRITE_OBJECT;
+	int write_object = flags & INDEX_WRITE_OBJECT;
 
 	if (!type)
 		type = OBJ_BLOB;
@@ -2400,7 +1266,7 @@ static int index_mem(struct index_state *istate,
 			size = nbuf.len;
 		}
 	}
-	if (flags & HASH_FORMAT_CHECK) {
+	if (flags & INDEX_FORMAT_CHECK) {
 		struct fsck_options opts = FSCK_OPTIONS_DEFAULT;
 
 		opts.strict = 1;
@@ -2426,7 +1292,7 @@ static int index_stream_convert_blob(struct index_state *istate,
 				     unsigned flags)
 {
 	int ret = 0;
-	const int write_object = flags & HASH_WRITE_OBJECT;
+	const int write_object = flags & INDEX_WRITE_OBJECT;
 	struct strbuf sbuf = STRBUF_INIT;
 
 	assert(path);
@@ -2491,28 +1357,6 @@ static int index_core(struct index_state *istate,
 	return ret;
 }
 
-/*
- * This creates one packfile per large blob unless bulk-checkin
- * machinery is "plugged".
- *
- * This also bypasses the usual "convert-to-git" dance, and that is on
- * purpose. We could write a streaming version of the converting
- * functions and insert that before feeding the data to fast-import
- * (or equivalent in-core API described above). However, that is
- * somewhat complicated, as we do not know the size of the filter
- * result, which we need to know beforehand when writing a git object.
- * Since the primary motivation for trying to stream from the working
- * tree file and to avoid mmaping it in core is to deal with large
- * binary blobs, they generally do not want to get any conversion, and
- * callers should avoid this code path when filters are requested.
- */
-static int index_blob_stream(struct object_id *oid, int fd, size_t size,
-			     const char *path,
-			     unsigned flags)
-{
-	return index_blob_bulk_checkin(oid, fd, size, path, flags);
-}
-
 int index_fd(struct index_state *istate, struct object_id *oid,
 	     int fd, struct stat *st,
 	     enum object_type type, const char *path, unsigned flags)
@@ -2533,8 +1377,8 @@ int index_fd(struct index_state *istate, struct object_id *oid,
 		ret = index_core(istate, oid, fd, xsize_t(st->st_size),
 				 type, path, flags);
 	else
-		ret = index_blob_stream(oid, fd, xsize_t(st->st_size), path,
-					flags);
+		ret = index_blob_bulk_checkin(oid, fd, xsize_t(st->st_size), path,
+					     flags);
 	close(fd);
 	return ret;
 }
@@ -2558,7 +1402,7 @@ int index_path(struct index_state *istate, struct object_id *oid,
 	case S_IFLNK:
 		if (strbuf_readlink(&sb, path, st->st_size))
 			return error_errno("readlink(\"%s\")", path);
-		if (!(flags & HASH_WRITE_OBJECT))
+		if (!(flags & INDEX_WRITE_OBJECT))
 			hash_object_file(the_hash_algo, sb.buf, sb.len,
 					 OBJ_BLOB, oid);
 		else if (write_object_file(sb.buf, sb.len, OBJ_BLOB, oid))
@@ -2588,16 +1432,6 @@ int read_pack_header(int fd, struct pack_header *header)
 	return 0;
 }
 
-void assert_oid_type(const struct object_id *oid, enum object_type expect)
-{
-	enum object_type type = oid_object_info(the_repository, oid, NULL);
-	if (type < 0)
-		die(_("%s is not a valid object"), oid_to_hex(oid));
-	if (type != expect)
-		die(_("%s is not a valid '%s' object"), oid_to_hex(oid),
-		    type_name(expect));
-}
-
 int for_each_file_in_obj_subdir(unsigned int subdir_nr,
 				struct strbuf *path,
 				each_loose_object_fn obj_cb,
diff --git a/object-file.h b/object-file.h
index 81b30d269c..c002fbe234 100644
--- a/object-file.h
+++ b/object-file.h
@@ -14,50 +14,37 @@ struct index_state;
  */
 extern int fetch_if_missing;
 
-#define HASH_WRITE_OBJECT 1
-#define HASH_FORMAT_CHECK 2
-#define HASH_RENORMALIZE  4
-#define HASH_SILENT 8
+enum {
+	INDEX_WRITE_OBJECT = (1 << 0),
+	INDEX_FORMAT_CHECK = (1 << 1),
+	INDEX_RENORMALIZE  = (1 << 2),
+};
+
 int index_fd(struct index_state *istate, struct object_id *oid, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 int index_path(struct index_state *istate, struct object_id *oid, const char *path, struct stat *st, unsigned flags);
 
+struct object_directory;
+
+const char *odb_loose_path(struct object_directory *odb,
+			   struct strbuf *buf,
+			   const struct object_id *oid);
+
 /*
- * Create the directory containing the named path, using care to be
- * somewhat safe against races. Return one of the scld_error values to
- * indicate success/failure. On error, set errno to describe the
- * problem.
- *
- * SCLD_VANISHED indicates that one of the ancestor directories of the
- * path existed at one point during the function call and then
- * suddenly vanished, probably because another process pruned the
- * directory while we were working.  To be robust against this kind of
- * race, callers might want to try invoking the function again when it
- * returns SCLD_VANISHED.
- *
- * safe_create_leading_directories() temporarily changes path while it
- * is working but restores it before returning.
- * safe_create_leading_directories_const() doesn't modify path, even
- * temporarily. Both these variants adjust the permissions of the
- * created directories to honor core.sharedRepository, so they are best
- * suited for files inside the git dir. For working tree files, use
- * safe_create_leading_directories_no_share() instead, as it ignores
- * the core.sharedRepository setting.
+ * Return true iff an alternate object database has a loose object
+ * with the specified name.  This function does not respect replace
+ * references.
  */
-enum scld_error {
-	SCLD_OK = 0,
-	SCLD_FAILED = -1,
-	SCLD_PERMS = -2,
-	SCLD_EXISTS = -3,
-	SCLD_VANISHED = -4
-};
-enum scld_error safe_create_leading_directories(char *path);
-enum scld_error safe_create_leading_directories_const(const char *path);
-enum scld_error safe_create_leading_directories_no_share(char *path);
+int has_loose_object_nonlocal(const struct object_id *);
 
-int mkdir_in_gitdir(const char *path);
+int has_loose_object(const struct object_id *);
 
-int git_open_cloexec(const char *name, int flags);
-#define git_open(name) git_open_cloexec(name, O_RDONLY)
+/**
+ * format_object_header() is a thin wrapper around s xsnprintf() that
+ * writes the initial "<type> <obj-len>" part of the loose object
+ * header. It returns the size that snprintf() returns + 1.
+ */
+int format_object_header(char *str, size_t size, enum object_type type,
+			 size_t objsize);
 
 /**
  * unpack_loose_header() initializes the data stream needed to unpack
@@ -99,6 +86,44 @@ enum unpack_loose_header_result unpack_loose_header(git_zstream *stream,
 struct object_info;
 int parse_loose_header(const char *hdr, struct object_info *oi);
 
+enum {
+	/*
+	 * By default, `write_object_file_literally()` does not actually write
+	 * anything into the object store, but only computes the object ID.
+	 * This flag changes that so that the object will be written as a loose
+	 * object and persisted.
+	 */
+	WRITE_OBJECT_FILE_PERSIST = (1 << 0),
+
+	/*
+	 * Do not print an error in case something gose wrong.
+	 */
+	WRITE_OBJECT_FILE_SILENT = (1 << 1),
+};
+
+int write_object_file_flags(const void *buf, unsigned long len,
+			    enum object_type type, struct object_id *oid,
+			    struct object_id *comapt_oid_in, unsigned flags);
+static inline int write_object_file(const void *buf, unsigned long len,
+				    enum object_type type, struct object_id *oid)
+{
+	return write_object_file_flags(buf, len, type, oid, NULL, 0);
+}
+
+struct input_stream {
+	const void *(*read)(struct input_stream *, unsigned long *len);
+	void *data;
+	int is_finished;
+};
+
+int write_object_file_literally(const void *buf, unsigned long len,
+				const char *type, struct object_id *oid,
+				unsigned flags);
+int stream_loose_object(struct input_stream *in_stream, size_t len,
+			struct object_id *oid);
+
+int force_object_loose(const struct object_id *oid, time_t mtime);
+
 /**
  * With in-core object data in "buf", rehash it to make sure the
  * object name actually matches "oid" to detect object corruption.
@@ -117,6 +142,10 @@ int check_object_signature(struct repository *r, const struct object_id *oid,
  */
 int stream_object_signature(struct repository *r, const struct object_id *oid);
 
+int loose_object_info(struct repository *r,
+		      const struct object_id *oid,
+		      struct object_info *oi, int flags);
+
 enum finalize_object_file_flags {
 	FOF_SKIP_COLLISION_CHECK = 1,
 };
@@ -128,10 +157,18 @@ int finalize_object_file_flags(const char *tmpfile, const char *filename,
 /* Helper to check and "touch" a file */
 int check_and_freshen_file(const char *fn, int freshen);
 
-void *read_object_with_reference(struct repository *r,
-				 const struct object_id *oid,
-				 enum object_type required_type,
-				 unsigned long *size,
-				 struct object_id *oid_ret);
+/*
+ * Open the loose object at path, check its hash, and return the contents,
+ * use the "oi" argument to assert things about the object, or e.g. populate its
+ * type, and size. If the object is a blob, then "contents" may return NULL,
+ * to allow streaming of large blobs.
+ *
+ * Returns 0 on success, negative on error (details may be written to stderr).
+ */
+int read_loose_object(const char *path,
+		      const struct object_id *expected_oid,
+		      struct object_id *real_oid,
+		      void **contents,
+		      struct object_info *oi);
 
 #endif /* OBJECT_FILE_H */
diff --git a/object-name.c b/object-name.c
index 91f731373a..2c751a5352 100644
--- a/object-name.c
+++ b/object-name.c
@@ -19,7 +19,7 @@
 #include "oidtree.h"
 #include "packfile.h"
 #include "pretty.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "read-cache-ll.h"
 #include "repo-settings.h"
 #include "repository.h"
diff --git a/object-store-ll.h b/object-store-ll.h
deleted file mode 100644
index cd3bd5bd99..0000000000
--- a/object-store-ll.h
+++ /dev/null
@@ -1,556 +0,0 @@
-#ifndef OBJECT_STORE_LL_H
-#define OBJECT_STORE_LL_H
-
-#include "hashmap.h"
-#include "object.h"
-#include "list.h"
-#include "thread-utils.h"
-#include "oidset.h"
-
-struct oidmap;
-struct oidtree;
-struct strbuf;
-struct repository;
-
-struct object_directory {
-	struct object_directory *next;
-
-	/*
-	 * Used to store the results of readdir(3) calls when we are OK
-	 * sacrificing accuracy due to races for speed. That includes
-	 * object existence with OBJECT_INFO_QUICK, as well as
-	 * our search for unique abbreviated hashes. Don't use it for tasks
-	 * requiring greater accuracy!
-	 *
-	 * Be sure to call odb_load_loose_cache() before using.
-	 */
-	uint32_t loose_objects_subdir_seen[8]; /* 256 bits */
-	struct oidtree *loose_objects_cache;
-
-	/* Map between object IDs for loose objects. */
-	struct loose_object_map *loose_map;
-
-	/*
-	 * This is a temporary object store created by the tmp_objdir
-	 * facility. Disable ref updates since the objects in the store
-	 * might be discarded on rollback.
-	 */
-	int disable_ref_updates;
-
-	/*
-	 * This object store is ephemeral, so there is no need to fsync.
-	 */
-	int will_destroy;
-
-	/*
-	 * Path to the alternative object store. If this is a relative path,
-	 * it is relative to the current working directory.
-	 */
-	char *path;
-};
-
-struct input_stream {
-	const void *(*read)(struct input_stream *, unsigned long *len);
-	void *data;
-	int is_finished;
-};
-
-void prepare_alt_odb(struct repository *r);
-int has_alt_odb(struct repository *r);
-char *compute_alternate_path(const char *path, struct strbuf *err);
-struct object_directory *find_odb(struct repository *r, const char *obj_dir);
-typedef int alt_odb_fn(struct object_directory *, void *);
-int foreach_alt_odb(alt_odb_fn, void*);
-typedef void alternate_ref_fn(const struct object_id *oid, void *);
-void for_each_alternate_ref(alternate_ref_fn, void *);
-
-/*
- * Add the directory to the on-disk alternates file; the new entry will also
- * take effect in the current process.
- */
-void add_to_alternates_file(const char *dir);
-
-/*
- * Add the directory to the in-memory list of alternates (along with any
- * recursive alternates it points to), but do not modify the on-disk alternates
- * file.
- */
-void add_to_alternates_memory(const char *dir);
-
-/*
- * Replace the current writable object directory with the specified temporary
- * object directory; returns the former primary object directory.
- */
-struct object_directory *set_temporary_primary_odb(const char *dir, int will_destroy);
-
-/*
- * Restore a previous ODB replaced by set_temporary_main_odb.
- */
-void restore_primary_odb(struct object_directory *restore_odb, const char *old_path);
-
-/*
- * Populate and return the loose object cache array corresponding to the
- * given object ID.
- */
-struct oidtree *odb_loose_cache(struct object_directory *odb,
-				  const struct object_id *oid);
-
-/* Empty the loose object cache for the specified object directory. */
-void odb_clear_loose_cache(struct object_directory *odb);
-
-/* Clear and free the specified object directory */
-void free_object_directory(struct object_directory *odb);
-
-struct packed_git {
-	struct hashmap_entry packmap_ent;
-	struct packed_git *next;
-	struct list_head mru;
-	struct pack_window *windows;
-	off_t pack_size;
-	const void *index_data;
-	size_t index_size;
-	uint32_t num_objects;
-	size_t crc_offset;
-	struct oidset bad_objects;
-	int index_version;
-	time_t mtime;
-	int pack_fd;
-	int index;              /* for builtin/pack-objects.c */
-	unsigned pack_local:1,
-		 pack_keep:1,
-		 pack_keep_in_core:1,
-		 freshened:1,
-		 do_not_close:1,
-		 pack_promisor:1,
-		 multi_pack_index:1,
-		 is_cruft:1;
-	unsigned char hash[GIT_MAX_RAWSZ];
-	struct revindex_entry *revindex;
-	const uint32_t *revindex_data;
-	const uint32_t *revindex_map;
-	size_t revindex_size;
-	/*
-	 * mtimes_map points at the beginning of the memory mapped region of
-	 * this pack's corresponding .mtimes file, and mtimes_size is the size
-	 * of that .mtimes file
-	 */
-	const uint32_t *mtimes_map;
-	size_t mtimes_size;
-
-	/* repo denotes the repository this packfile belongs to */
-	struct repository *repo;
-
-	/* something like ".git/objects/pack/xxxxx.pack" */
-	char pack_name[FLEX_ARRAY]; /* more */
-};
-
-struct multi_pack_index;
-
-static inline int pack_map_entry_cmp(const void *cmp_data UNUSED,
-				     const struct hashmap_entry *entry,
-				     const struct hashmap_entry *entry2,
-				     const void *keydata)
-{
-	const char *key = keydata;
-	const struct packed_git *pg1, *pg2;
-
-	pg1 = container_of(entry, const struct packed_git, packmap_ent);
-	pg2 = container_of(entry2, const struct packed_git, packmap_ent);
-
-	return strcmp(pg1->pack_name, key ? key : pg2->pack_name);
-}
-
-struct raw_object_store {
-	/*
-	 * Set of all object directories; the main directory is first (and
-	 * cannot be NULL after initialization). Subsequent directories are
-	 * alternates.
-	 */
-	struct object_directory *odb;
-	struct object_directory **odb_tail;
-	struct kh_odb_path_map *odb_by_path;
-
-	int loaded_alternates;
-
-	/*
-	 * A list of alternate object directories loaded from the environment;
-	 * this should not generally need to be accessed directly, but will
-	 * populate the "odb" list when prepare_alt_odb() is run.
-	 */
-	char *alternate_db;
-
-	/*
-	 * Objects that should be substituted by other objects
-	 * (see git-replace(1)).
-	 */
-	struct oidmap *replace_map;
-	unsigned replace_map_initialized : 1;
-	pthread_mutex_t replace_mutex; /* protect object replace functions */
-
-	struct commit_graph *commit_graph;
-	unsigned commit_graph_attempted : 1; /* if loading has been attempted */
-
-	/*
-	 * private data
-	 *
-	 * should only be accessed directly by packfile.c and midx.c
-	 */
-	struct multi_pack_index *multi_pack_index;
-
-	/*
-	 * private data
-	 *
-	 * should only be accessed directly by packfile.c
-	 */
-
-	struct packed_git *packed_git;
-	/* A most-recently-used ordered version of the packed_git list. */
-	struct list_head packed_git_mru;
-
-	struct {
-		struct packed_git **packs;
-		unsigned flags;
-	} kept_pack_cache;
-
-	/*
-	 * A map of packfiles to packed_git structs for tracking which
-	 * packs have been loaded already.
-	 */
-	struct hashmap pack_map;
-
-	/*
-	 * A fast, rough count of the number of objects in the repository.
-	 * These two fields are not meant for direct access. Use
-	 * repo_approximate_object_count() instead.
-	 */
-	unsigned long approximate_object_count;
-	unsigned approximate_object_count_valid : 1;
-
-	/*
-	 * Whether packed_git has already been populated with this repository's
-	 * packs.
-	 */
-	unsigned packed_git_initialized : 1;
-};
-
-struct raw_object_store *raw_object_store_new(void);
-void raw_object_store_clear(struct raw_object_store *o);
-
-/*
- * Create a temporary file rooted in the object database directory, or
- * die on failure. The filename is taken from "pattern", which should have the
- * usual "XXXXXX" trailer, and the resulting filename is written into the
- * "template" buffer. Returns the open descriptor.
- */
-int odb_mkstemp(struct strbuf *temp_filename, const char *pattern);
-
-/*
- * Create a pack .keep file named "name" (which should generally be the output
- * of odb_pack_name). Returns a file descriptor opened for writing, or -1 on
- * error.
- */
-int odb_pack_keep(const char *name);
-
-/*
- * Put in `buf` the name of the file in the local object database that
- * would be used to store a loose object with the specified oid.
- */
-const char *loose_object_path(struct repository *r, struct strbuf *buf,
-			      const struct object_id *oid);
-
-void *map_loose_object(struct repository *r, const struct object_id *oid,
-		       unsigned long *size);
-
-void *repo_read_object_file(struct repository *r,
-			    const struct object_id *oid,
-			    enum object_type *type,
-			    unsigned long *size);
-
-/* Read and unpack an object file into memory, write memory to an object file */
-int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
-
-void hash_object_file(const struct git_hash_algo *algo, const void *buf,
-		      unsigned long len, enum object_type type,
-		      struct object_id *oid);
-
-int write_object_file_flags(const void *buf, unsigned long len,
-			    enum object_type type, struct object_id *oid,
-			    struct object_id *comapt_oid_in, unsigned flags);
-static inline int write_object_file(const void *buf, unsigned long len,
-				    enum object_type type, struct object_id *oid)
-{
-	return write_object_file_flags(buf, len, type, oid, NULL, 0);
-}
-
-int write_object_file_literally(const void *buf, unsigned long len,
-				const char *type, struct object_id *oid,
-				unsigned flags);
-int stream_loose_object(struct input_stream *in_stream, size_t len,
-			struct object_id *oid);
-
-/*
- * Add an object file to the in-memory object store, without writing it
- * to disk.
- *
- * Callers are responsible for calling write_object_file to record the
- * object in persistent storage before writing any other new objects
- * that reference it.
- */
-int pretend_object_file(void *, unsigned long, enum object_type,
-			struct object_id *oid);
-
-int force_object_loose(const struct object_id *oid, time_t mtime);
-
-struct object_info {
-	/* Request */
-	enum object_type *typep;
-	unsigned long *sizep;
-	off_t *disk_sizep;
-	struct object_id *delta_base_oid;
-	struct strbuf *type_name;
-	void **contentp;
-
-	/* Response */
-	enum {
-		OI_CACHED,
-		OI_LOOSE,
-		OI_PACKED,
-		OI_DBCACHED
-	} whence;
-	union {
-		/*
-		 * struct {
-		 * 	... Nothing to expose in this case
-		 * } cached;
-		 * struct {
-		 * 	... Nothing to expose in this case
-		 * } loose;
-		 */
-		struct {
-			struct packed_git *pack;
-			off_t offset;
-			unsigned int is_delta;
-		} packed;
-	} u;
-};
-
-/*
- * Initializer for a "struct object_info" that wants no items. You may
- * also memset() the memory to all-zeroes.
- */
-#define OBJECT_INFO_INIT { 0 }
-
-/* Invoke lookup_replace_object() on the given hash */
-#define OBJECT_INFO_LOOKUP_REPLACE 1
-/* Allow reading from a loose object file of unknown/bogus type */
-#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
-/* Do not retry packed storage after checking packed and loose storage */
-#define OBJECT_INFO_QUICK 8
-/*
- * Do not attempt to fetch the object if missing (even if fetch_is_missing is
- * nonzero).
- */
-#define OBJECT_INFO_SKIP_FETCH_OBJECT 16
-/*
- * This is meant for bulk prefetching of missing blobs in a partial
- * clone. Implies OBJECT_INFO_SKIP_FETCH_OBJECT and OBJECT_INFO_QUICK
- */
-#define OBJECT_INFO_FOR_PREFETCH (OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK)
-
-/* Die if object corruption (not just an object being missing) was detected. */
-#define OBJECT_INFO_DIE_IF_CORRUPT 32
-
-int oid_object_info_extended(struct repository *r,
-			     const struct object_id *,
-			     struct object_info *, unsigned flags);
-
-/*
- * Open the loose object at path, check its hash, and return the contents,
- * use the "oi" argument to assert things about the object, or e.g. populate its
- * type, and size. If the object is a blob, then "contents" may return NULL,
- * to allow streaming of large blobs.
- *
- * Returns 0 on success, negative on error (details may be written to stderr).
- */
-int read_loose_object(const char *path,
-		      const struct object_id *expected_oid,
-		      struct object_id *real_oid,
-		      void **contents,
-		      struct object_info *oi);
-
-/* Retry packed storage after checking packed and loose storage */
-#define HAS_OBJECT_RECHECK_PACKED 1
-
-/*
- * Returns 1 if the object exists. This function will not lazily fetch objects
- * in a partial clone.
- */
-int has_object(struct repository *r, const struct object_id *oid,
-	       unsigned flags);
-
-/*
- * These macros and functions are deprecated. If checking existence for an
- * object that is likely to be missing and/or whose absence is relatively
- * inconsequential (or is consequential but the caller is prepared to handle
- * it), use has_object(), which has better defaults (no lazy fetch in a partial
- * clone and no rechecking of packed storage). In the unlikely event that a
- * caller needs to assert existence of an object that it fully expects to
- * exist, and wants to trigger a lazy fetch in a partial clone, use
- * oid_object_info_extended() with a NULL struct object_info.
- *
- * These functions can be removed once all callers have migrated to
- * has_object() and/or oid_object_info_extended().
- */
-int repo_has_object_file(struct repository *r, const struct object_id *oid);
-int repo_has_object_file_with_flags(struct repository *r,
-				    const struct object_id *oid, int flags);
-
-/*
- * Return true iff an alternate object database has a loose object
- * with the specified name.  This function does not respect replace
- * references.
- */
-int has_loose_object_nonlocal(const struct object_id *);
-
-int has_loose_object(const struct object_id *);
-
-/**
- * format_object_header() is a thin wrapper around s xsnprintf() that
- * writes the initial "<type> <obj-len>" part of the loose object
- * header. It returns the size that snprintf() returns + 1.
- */
-int format_object_header(char *str, size_t size, enum object_type type,
-			 size_t objsize);
-
-void assert_oid_type(const struct object_id *oid, enum object_type expect);
-
-/*
- * Enabling the object read lock allows multiple threads to safely call the
- * following functions in parallel: repo_read_object_file(),
- * read_object_with_reference(), oid_object_info() and oid_object_info_extended().
- *
- * obj_read_lock() and obj_read_unlock() may also be used to protect other
- * section which cannot execute in parallel with object reading. Since the used
- * lock is a recursive mutex, these sections can even contain calls to object
- * reading functions. However, beware that in these cases zlib inflation won't
- * be performed in parallel, losing performance.
- *
- * TODO: oid_object_info_extended()'s call stack has a recursive behavior. If
- * any of its callees end up calling it, this recursive call won't benefit from
- * parallel inflation.
- */
-void enable_obj_read_lock(void);
-void disable_obj_read_lock(void);
-
-extern int obj_read_use_lock;
-extern pthread_mutex_t obj_read_mutex;
-
-static inline void obj_read_lock(void)
-{
-	if(obj_read_use_lock)
-		pthread_mutex_lock(&obj_read_mutex);
-}
-
-static inline void obj_read_unlock(void)
-{
-	if(obj_read_use_lock)
-		pthread_mutex_unlock(&obj_read_mutex);
-}
-
-/*
- * Iterate over the files in the loose-object parts of the object
- * directory "path", triggering the following callbacks:
- *
- *  - loose_object is called for each loose object we find.
- *
- *  - loose_cruft is called for any files that do not appear to be
- *    loose objects. Note that we only look in the loose object
- *    directories "objects/[0-9a-f]{2}/", so we will not report
- *    "objects/foobar" as cruft.
- *
- *  - loose_subdir is called for each top-level hashed subdirectory
- *    of the object directory (e.g., "$OBJDIR/f0"). It is called
- *    after the objects in the directory are processed.
- *
- * Any callback that is NULL will be ignored. Callbacks returning non-zero
- * will end the iteration.
- *
- * In the "buf" variant, "path" is a strbuf which will also be used as a
- * scratch buffer, but restored to its original contents before
- * the function returns.
- */
-typedef int each_loose_object_fn(const struct object_id *oid,
-				 const char *path,
-				 void *data);
-typedef int each_loose_cruft_fn(const char *basename,
-				const char *path,
-				void *data);
-typedef int each_loose_subdir_fn(unsigned int nr,
-				 const char *path,
-				 void *data);
-int for_each_file_in_obj_subdir(unsigned int subdir_nr,
-				struct strbuf *path,
-				each_loose_object_fn obj_cb,
-				each_loose_cruft_fn cruft_cb,
-				each_loose_subdir_fn subdir_cb,
-				void *data);
-int for_each_loose_file_in_objdir(const char *path,
-				  each_loose_object_fn obj_cb,
-				  each_loose_cruft_fn cruft_cb,
-				  each_loose_subdir_fn subdir_cb,
-				  void *data);
-int for_each_loose_file_in_objdir_buf(struct strbuf *path,
-				      each_loose_object_fn obj_cb,
-				      each_loose_cruft_fn cruft_cb,
-				      each_loose_subdir_fn subdir_cb,
-				      void *data);
-
-/* Flags for for_each_*_object() below. */
-enum for_each_object_flags {
-	/* Iterate only over local objects, not alternates. */
-	FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
-
-	/* Only iterate over packs obtained from the promisor remote. */
-	FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
-
-	/*
-	 * Visit objects within a pack in packfile order rather than .idx order
-	 */
-	FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
-
-	/* Only iterate over packs that are not marked as kept in-core. */
-	FOR_EACH_OBJECT_SKIP_IN_CORE_KEPT_PACKS = (1<<3),
-
-	/* Only iterate over packs that do not have .keep files. */
-	FOR_EACH_OBJECT_SKIP_ON_DISK_KEPT_PACKS = (1<<4),
-};
-
-/*
- * Iterate over all accessible loose objects without respect to
- * reachability. By default, this includes both local and alternate objects.
- * The order in which objects are visited is unspecified.
- *
- * Any flags specific to packs are ignored.
- */
-int for_each_loose_object(each_loose_object_fn, void *,
-			  enum for_each_object_flags flags);
-
-/*
- * Iterate over all accessible packed objects without respect to reachability.
- * By default, this includes both local and alternate packs.
- *
- * Note that some objects may appear twice if they are found in multiple packs.
- * Each pack is visited in an unspecified order. By default, objects within a
- * pack are visited in pack-idx order (i.e., sorted by oid).
- */
-typedef int each_packed_object_fn(const struct object_id *oid,
-				  struct packed_git *pack,
-				  uint32_t pos,
-				  void *data);
-int for_each_object_in_pack(struct packed_git *p,
-			    each_packed_object_fn, void *data,
-			    enum for_each_object_flags flags);
-int for_each_packed_object(struct repository *repo, each_packed_object_fn cb,
-			   void *data, enum for_each_object_flags flags);
-
-#endif /* OBJECT_STORE_LL_H */
diff --git a/object-store.c b/object-store.c
new file mode 100644
index 0000000000..6ab50d25d3
--- /dev/null
+++ b/object-store.c
@@ -0,0 +1,1050 @@
+#define USE_THE_REPOSITORY_VARIABLE
+
+#include "git-compat-util.h"
+#include "abspath.h"
+#include "commit-graph.h"
+#include "config.h"
+#include "dir.h"
+#include "environment.h"
+#include "gettext.h"
+#include "hex.h"
+#include "khash.h"
+#include "lockfile.h"
+#include "loose.h"
+#include "object-file-convert.h"
+#include "object-file.h"
+#include "object-store.h"
+#include "packfile.h"
+#include "path.h"
+#include "promisor-remote.h"
+#include "quote.h"
+#include "replace-object.h"
+#include "run-command.h"
+#include "setup.h"
+#include "strbuf.h"
+#include "strvec.h"
+#include "submodule.h"
+#include "write-or-die.h"
+
+KHASH_INIT(odb_path_map, const char * /* key: odb_path */,
+	struct object_directory *, 1, fspathhash, fspatheq)
+
+/*
+ * This is meant to hold a *small* number of objects that you would
+ * want repo_read_object_file() to be able to return, but yet you do not want
+ * to write them into the object store (e.g. a browse-only
+ * application).
+ */
+struct cached_object_entry {
+	struct object_id oid;
+	struct cached_object {
+		enum object_type type;
+		const void *buf;
+		unsigned long size;
+	} value;
+};
+
+static const struct cached_object *find_cached_object(struct raw_object_store *object_store,
+						      const struct object_id *oid)
+{
+	static const struct cached_object empty_tree = {
+		.type = OBJ_TREE,
+		.buf = "",
+	};
+	const struct cached_object_entry *co = object_store->cached_objects;
+
+	for (size_t i = 0; i < object_store->cached_object_nr; i++, co++)
+		if (oideq(&co->oid, oid))
+			return &co->value;
+
+	if (oid->algo && oideq(oid, hash_algos[oid->algo].empty_tree))
+		return &empty_tree;
+
+	return NULL;
+}
+
+int odb_mkstemp(struct strbuf *temp_filename, const char *pattern)
+{
+	int fd;
+	/*
+	 * we let the umask do its job, don't try to be more
+	 * restrictive except to remove write permission.
+	 */
+	int mode = 0444;
+	repo_git_path_replace(the_repository, temp_filename, "objects/%s", pattern);
+	fd = git_mkstemp_mode(temp_filename->buf, mode);
+	if (0 <= fd)
+		return fd;
+
+	/* slow path */
+	/* some mkstemp implementations erase temp_filename on failure */
+	repo_git_path_replace(the_repository, temp_filename, "objects/%s", pattern);
+	safe_create_leading_directories(the_repository, temp_filename->buf);
+	return xmkstemp_mode(temp_filename->buf, mode);
+}
+
+int odb_pack_keep(const char *name)
+{
+	int fd;
+
+	fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
+	if (0 <= fd)
+		return fd;
+
+	/* slow path */
+	safe_create_leading_directories_const(the_repository, name);
+	return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
+}
+
+const char *loose_object_path(struct repository *r, struct strbuf *buf,
+			      const struct object_id *oid)
+{
+	return odb_loose_path(r->objects->odb, buf, oid);
+}
+
+/*
+ * Return non-zero iff the path is usable as an alternate object database.
+ */
+static int alt_odb_usable(struct raw_object_store *o,
+			  struct strbuf *path,
+			  const char *normalized_objdir, khiter_t *pos)
+{
+	int r;
+
+	/* Detect cases where alternate disappeared */
+	if (!is_directory(path->buf)) {
+		error(_("object directory %s does not exist; "
+			"check .git/objects/info/alternates"),
+		      path->buf);
+		return 0;
+	}
+
+	/*
+	 * Prevent the common mistake of listing the same
+	 * thing twice, or object directory itself.
+	 */
+	if (!o->odb_by_path) {
+		khiter_t p;
+
+		o->odb_by_path = kh_init_odb_path_map();
+		assert(!o->odb->next);
+		p = kh_put_odb_path_map(o->odb_by_path, o->odb->path, &r);
+		assert(r == 1); /* never used */
+		kh_value(o->odb_by_path, p) = o->odb;
+	}
+	if (fspatheq(path->buf, normalized_objdir))
+		return 0;
+	*pos = kh_put_odb_path_map(o->odb_by_path, path->buf, &r);
+	/* r: 0 = exists, 1 = never used, 2 = deleted */
+	return r == 0 ? 0 : 1;
+}
+
+/*
+ * Prepare alternate object database registry.
+ *
+ * The variable alt_odb_list points at the list of struct
+ * object_directory.  The elements on this list come from
+ * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
+ * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
+ * whose contents is similar to that environment variable but can be
+ * LF separated.  Its base points at a statically allocated buffer that
+ * contains "/the/directory/corresponding/to/.git/objects/...", while
+ * its name points just after the slash at the end of ".git/objects/"
+ * in the example above, and has enough space to hold all hex characters
+ * of the object ID, an extra slash for the first level indirection, and
+ * the terminating NUL.
+ */
+static void read_info_alternates(struct repository *r,
+				 const char *relative_base,
+				 int depth);
+static int link_alt_odb_entry(struct repository *r, const struct strbuf *entry,
+	const char *relative_base, int depth, const char *normalized_objdir)
+{
+	struct object_directory *ent;
+	struct strbuf pathbuf = STRBUF_INIT;
+	struct strbuf tmp = STRBUF_INIT;
+	khiter_t pos;
+	int ret = -1;
+
+	if (!is_absolute_path(entry->buf) && relative_base) {
+		strbuf_realpath(&pathbuf, relative_base, 1);
+		strbuf_addch(&pathbuf, '/');
+	}
+	strbuf_addbuf(&pathbuf, entry);
+
+	if (!strbuf_realpath(&tmp, pathbuf.buf, 0)) {
+		error(_("unable to normalize alternate object path: %s"),
+		      pathbuf.buf);
+		goto error;
+	}
+	strbuf_swap(&pathbuf, &tmp);
+
+	/*
+	 * The trailing slash after the directory name is given by
+	 * this function at the end. Remove duplicates.
+	 */
+	while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
+		strbuf_setlen(&pathbuf, pathbuf.len - 1);
+
+	if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir, &pos))
+		goto error;
+
+	CALLOC_ARRAY(ent, 1);
+	/* pathbuf.buf is already in r->objects->odb_by_path */
+	ent->path = strbuf_detach(&pathbuf, NULL);
+
+	/* add the alternate entry */
+	*r->objects->odb_tail = ent;
+	r->objects->odb_tail = &(ent->next);
+	ent->next = NULL;
+	assert(r->objects->odb_by_path);
+	kh_value(r->objects->odb_by_path, pos) = ent;
+
+	/* recursively add alternates */
+	read_info_alternates(r, ent->path, depth + 1);
+	ret = 0;
+ error:
+	strbuf_release(&tmp);
+	strbuf_release(&pathbuf);
+	return ret;
+}
+
+static const char *parse_alt_odb_entry(const char *string,
+				       int sep,
+				       struct strbuf *out)
+{
+	const char *end;
+
+	strbuf_reset(out);
+
+	if (*string == '#') {
+		/* comment; consume up to next separator */
+		end = strchrnul(string, sep);
+	} else if (*string == '"' && !unquote_c_style(out, string, &end)) {
+		/*
+		 * quoted path; unquote_c_style has copied the
+		 * data for us and set "end". Broken quoting (e.g.,
+		 * an entry that doesn't end with a quote) falls
+		 * back to the unquoted case below.
+		 */
+	} else {
+		/* normal, unquoted path */
+		end = strchrnul(string, sep);
+		strbuf_add(out, string, end - string);
+	}
+
+	if (*end)
+		end++;
+	return end;
+}
+
+static void link_alt_odb_entries(struct repository *r, const char *alt,
+				 int sep, const char *relative_base, int depth)
+{
+	struct strbuf objdirbuf = STRBUF_INIT;
+	struct strbuf entry = STRBUF_INIT;
+
+	if (!alt || !*alt)
+		return;
+
+	if (depth > 5) {
+		error(_("%s: ignoring alternate object stores, nesting too deep"),
+				relative_base);
+		return;
+	}
+
+	strbuf_realpath(&objdirbuf, r->objects->odb->path, 1);
+
+	while (*alt) {
+		alt = parse_alt_odb_entry(alt, sep, &entry);
+		if (!entry.len)
+			continue;
+		link_alt_odb_entry(r, &entry,
+				   relative_base, depth, objdirbuf.buf);
+	}
+	strbuf_release(&entry);
+	strbuf_release(&objdirbuf);
+}
+
+static void read_info_alternates(struct repository *r,
+				 const char *relative_base,
+				 int depth)
+{
+	char *path;
+	struct strbuf buf = STRBUF_INIT;
+
+	path = xstrfmt("%s/info/alternates", relative_base);
+	if (strbuf_read_file(&buf, path, 1024) < 0) {
+		warn_on_fopen_errors(path);
+		free(path);
+		return;
+	}
+
+	link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
+	strbuf_release(&buf);
+	free(path);
+}
+
+void add_to_alternates_file(const char *reference)
+{
+	struct lock_file lock = LOCK_INIT;
+	char *alts = repo_git_path(the_repository, "objects/info/alternates");
+	FILE *in, *out;
+	int found = 0;
+
+	hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
+	out = fdopen_lock_file(&lock, "w");
+	if (!out)
+		die_errno(_("unable to fdopen alternates lockfile"));
+
+	in = fopen(alts, "r");
+	if (in) {
+		struct strbuf line = STRBUF_INIT;
+
+		while (strbuf_getline(&line, in) != EOF) {
+			if (!strcmp(reference, line.buf)) {
+				found = 1;
+				break;
+			}
+			fprintf_or_die(out, "%s\n", line.buf);
+		}
+
+		strbuf_release(&line);
+		fclose(in);
+	}
+	else if (errno != ENOENT)
+		die_errno(_("unable to read alternates file"));
+
+	if (found) {
+		rollback_lock_file(&lock);
+	} else {
+		fprintf_or_die(out, "%s\n", reference);
+		if (commit_lock_file(&lock))
+			die_errno(_("unable to move new alternates file into place"));
+		if (the_repository->objects->loaded_alternates)
+			link_alt_odb_entries(the_repository, reference,
+					     '\n', NULL, 0);
+	}
+	free(alts);
+}
+
+void add_to_alternates_memory(const char *reference)
+{
+	/*
+	 * Make sure alternates are initialized, or else our entry may be
+	 * overwritten when they are.
+	 */
+	prepare_alt_odb(the_repository);
+
+	link_alt_odb_entries(the_repository, reference,
+			     '\n', NULL, 0);
+}
+
+struct object_directory *set_temporary_primary_odb(const char *dir, int will_destroy)
+{
+	struct object_directory *new_odb;
+
+	/*
+	 * Make sure alternates are initialized, or else our entry may be
+	 * overwritten when they are.
+	 */
+	prepare_alt_odb(the_repository);
+
+	/*
+	 * Make a new primary odb and link the old primary ODB in as an
+	 * alternate
+	 */
+	new_odb = xcalloc(1, sizeof(*new_odb));
+	new_odb->path = xstrdup(dir);
+
+	/*
+	 * Disable ref updates while a temporary odb is active, since
+	 * the objects in the database may roll back.
+	 */
+	new_odb->disable_ref_updates = 1;
+	new_odb->will_destroy = will_destroy;
+	new_odb->next = the_repository->objects->odb;
+	the_repository->objects->odb = new_odb;
+	return new_odb->next;
+}
+
+static void free_object_directory(struct object_directory *odb)
+{
+	free(odb->path);
+	odb_clear_loose_cache(odb);
+	loose_object_map_clear(&odb->loose_map);
+	free(odb);
+}
+
+void restore_primary_odb(struct object_directory *restore_odb, const char *old_path)
+{
+	struct object_directory *cur_odb = the_repository->objects->odb;
+
+	if (strcmp(old_path, cur_odb->path))
+		BUG("expected %s as primary object store; found %s",
+		    old_path, cur_odb->path);
+
+	if (cur_odb->next != restore_odb)
+		BUG("we expect the old primary object store to be the first alternate");
+
+	the_repository->objects->odb = restore_odb;
+	free_object_directory(cur_odb);
+}
+
+/*
+ * Compute the exact path an alternate is at and returns it. In case of
+ * error NULL is returned and the human readable error is added to `err`
+ * `path` may be relative and should point to $GIT_DIR.
+ * `err` must not be null.
+ */
+char *compute_alternate_path(const char *path, struct strbuf *err)
+{
+	char *ref_git = NULL;
+	const char *repo;
+	int seen_error = 0;
+
+	ref_git = real_pathdup(path, 0);
+	if (!ref_git) {
+		seen_error = 1;
+		strbuf_addf(err, _("path '%s' does not exist"), path);
+		goto out;
+	}
+
+	repo = read_gitfile(ref_git);
+	if (!repo)
+		repo = read_gitfile(mkpath("%s/.git", ref_git));
+	if (repo) {
+		free(ref_git);
+		ref_git = xstrdup(repo);
+	}
+
+	if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
+		char *ref_git_git = mkpathdup("%s/.git", ref_git);
+		free(ref_git);
+		ref_git = ref_git_git;
+	} else if (!is_directory(mkpath("%s/objects", ref_git))) {
+		struct strbuf sb = STRBUF_INIT;
+		seen_error = 1;
+		if (get_common_dir(&sb, ref_git)) {
+			strbuf_addf(err,
+				    _("reference repository '%s' as a linked "
+				      "checkout is not supported yet."),
+				    path);
+			goto out;
+		}
+
+		strbuf_addf(err, _("reference repository '%s' is not a "
+					"local repository."), path);
+		goto out;
+	}
+
+	if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
+		strbuf_addf(err, _("reference repository '%s' is shallow"),
+			    path);
+		seen_error = 1;
+		goto out;
+	}
+
+	if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
+		strbuf_addf(err,
+			    _("reference repository '%s' is grafted"),
+			    path);
+		seen_error = 1;
+		goto out;
+	}
+
+out:
+	if (seen_error) {
+		FREE_AND_NULL(ref_git);
+	}
+
+	return ref_git;
+}
+
+struct object_directory *find_odb(struct repository *r, const char *obj_dir)
+{
+	struct object_directory *odb;
+	char *obj_dir_real = real_pathdup(obj_dir, 1);
+	struct strbuf odb_path_real = STRBUF_INIT;
+
+	prepare_alt_odb(r);
+	for (odb = r->objects->odb; odb; odb = odb->next) {
+		strbuf_realpath(&odb_path_real, odb->path, 1);
+		if (!strcmp(obj_dir_real, odb_path_real.buf))
+			break;
+	}
+
+	free(obj_dir_real);
+	strbuf_release(&odb_path_real);
+
+	if (!odb)
+		die(_("could not find object directory matching %s"), obj_dir);
+	return odb;
+}
+
+static void fill_alternate_refs_command(struct child_process *cmd,
+					const char *repo_path)
+{
+	const char *value;
+
+	if (!git_config_get_value("core.alternateRefsCommand", &value)) {
+		cmd->use_shell = 1;
+
+		strvec_push(&cmd->args, value);
+		strvec_push(&cmd->args, repo_path);
+	} else {
+		cmd->git_cmd = 1;
+
+		strvec_pushf(&cmd->args, "--git-dir=%s", repo_path);
+		strvec_push(&cmd->args, "for-each-ref");
+		strvec_push(&cmd->args, "--format=%(objectname)");
+
+		if (!git_config_get_value("core.alternateRefsPrefixes", &value)) {
+			strvec_push(&cmd->args, "--");
+			strvec_split(&cmd->args, value);
+		}
+	}
+
+	strvec_pushv(&cmd->env, (const char **)local_repo_env);
+	cmd->out = -1;
+}
+
+static void read_alternate_refs(const char *path,
+				alternate_ref_fn *cb,
+				void *data)
+{
+	struct child_process cmd = CHILD_PROCESS_INIT;
+	struct strbuf line = STRBUF_INIT;
+	FILE *fh;
+
+	fill_alternate_refs_command(&cmd, path);
+
+	if (start_command(&cmd))
+		return;
+
+	fh = xfdopen(cmd.out, "r");
+	while (strbuf_getline_lf(&line, fh) != EOF) {
+		struct object_id oid;
+		const char *p;
+
+		if (parse_oid_hex(line.buf, &oid, &p) || *p) {
+			warning(_("invalid line while parsing alternate refs: %s"),
+				line.buf);
+			break;
+		}
+
+		cb(&oid, data);
+	}
+
+	fclose(fh);
+	finish_command(&cmd);
+	strbuf_release(&line);
+}
+
+struct alternate_refs_data {
+	alternate_ref_fn *fn;
+	void *data;
+};
+
+static int refs_from_alternate_cb(struct object_directory *e,
+				  void *data)
+{
+	struct strbuf path = STRBUF_INIT;
+	size_t base_len;
+	struct alternate_refs_data *cb = data;
+
+	if (!strbuf_realpath(&path, e->path, 0))
+		goto out;
+	if (!strbuf_strip_suffix(&path, "/objects"))
+		goto out;
+	base_len = path.len;
+
+	/* Is this a git repository with refs? */
+	strbuf_addstr(&path, "/refs");
+	if (!is_directory(path.buf))
+		goto out;
+	strbuf_setlen(&path, base_len);
+
+	read_alternate_refs(path.buf, cb->fn, cb->data);
+
+out:
+	strbuf_release(&path);
+	return 0;
+}
+
+void for_each_alternate_ref(alternate_ref_fn fn, void *data)
+{
+	struct alternate_refs_data cb;
+	cb.fn = fn;
+	cb.data = data;
+	foreach_alt_odb(refs_from_alternate_cb, &cb);
+}
+
+int foreach_alt_odb(alt_odb_fn fn, void *cb)
+{
+	struct object_directory *ent;
+	int r = 0;
+
+	prepare_alt_odb(the_repository);
+	for (ent = the_repository->objects->odb->next; ent; ent = ent->next) {
+		r = fn(ent, cb);
+		if (r)
+			break;
+	}
+	return r;
+}
+
+void prepare_alt_odb(struct repository *r)
+{
+	if (r->objects->loaded_alternates)
+		return;
+
+	link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
+
+	read_info_alternates(r, r->objects->odb->path, 0);
+	r->objects->loaded_alternates = 1;
+}
+
+int has_alt_odb(struct repository *r)
+{
+	prepare_alt_odb(r);
+	return !!r->objects->odb->next;
+}
+
+int obj_read_use_lock = 0;
+pthread_mutex_t obj_read_mutex;
+
+void enable_obj_read_lock(void)
+{
+	if (obj_read_use_lock)
+		return;
+
+	obj_read_use_lock = 1;
+	init_recursive_mutex(&obj_read_mutex);
+}
+
+void disable_obj_read_lock(void)
+{
+	if (!obj_read_use_lock)
+		return;
+
+	obj_read_use_lock = 0;
+	pthread_mutex_destroy(&obj_read_mutex);
+}
+
+int fetch_if_missing = 1;
+
+static int do_oid_object_info_extended(struct repository *r,
+				       const struct object_id *oid,
+				       struct object_info *oi, unsigned flags)
+{
+	static struct object_info blank_oi = OBJECT_INFO_INIT;
+	const struct cached_object *co;
+	struct pack_entry e;
+	int rtype;
+	const struct object_id *real = oid;
+	int already_retried = 0;
+
+
+	if (flags & OBJECT_INFO_LOOKUP_REPLACE)
+		real = lookup_replace_object(r, oid);
+
+	if (is_null_oid(real))
+		return -1;
+
+	if (!oi)
+		oi = &blank_oi;
+
+	co = find_cached_object(r->objects, real);
+	if (co) {
+		if (oi->typep)
+			*(oi->typep) = co->type;
+		if (oi->sizep)
+			*(oi->sizep) = co->size;
+		if (oi->disk_sizep)
+			*(oi->disk_sizep) = 0;
+		if (oi->delta_base_oid)
+			oidclr(oi->delta_base_oid, the_repository->hash_algo);
+		if (oi->type_name)
+			strbuf_addstr(oi->type_name, type_name(co->type));
+		if (oi->contentp)
+			*oi->contentp = xmemdupz(co->buf, co->size);
+		oi->whence = OI_CACHED;
+		return 0;
+	}
+
+	while (1) {
+		if (find_pack_entry(r, real, &e))
+			break;
+
+		/* Most likely it's a loose object. */
+		if (!loose_object_info(r, real, oi, flags))
+			return 0;
+
+		/* Not a loose object; someone else may have just packed it. */
+		if (!(flags & OBJECT_INFO_QUICK)) {
+			reprepare_packed_git(r);
+			if (find_pack_entry(r, real, &e))
+				break;
+		}
+
+		/*
+		 * If r is the_repository, this might be an attempt at
+		 * accessing a submodule object as if it were in the_repository
+		 * (having called add_submodule_odb() on that submodule's ODB).
+		 * If any such ODBs exist, register them and try again.
+		 */
+		if (r == the_repository &&
+		    register_all_submodule_odb_as_alternates())
+			/* We added some alternates; retry */
+			continue;
+
+		/* Check if it is a missing object */
+		if (fetch_if_missing && repo_has_promisor_remote(r) &&
+		    !already_retried &&
+		    !(flags & OBJECT_INFO_SKIP_FETCH_OBJECT)) {
+			promisor_remote_get_direct(r, real, 1);
+			already_retried = 1;
+			continue;
+		}
+
+		if (flags & OBJECT_INFO_DIE_IF_CORRUPT) {
+			const struct packed_git *p;
+			if ((flags & OBJECT_INFO_LOOKUP_REPLACE) && !oideq(real, oid))
+				die(_("replacement %s not found for %s"),
+				    oid_to_hex(real), oid_to_hex(oid));
+			if ((p = has_packed_and_bad(r, real)))
+				die(_("packed object %s (stored in %s) is corrupt"),
+				    oid_to_hex(real), p->pack_name);
+		}
+		return -1;
+	}
+
+	if (oi == &blank_oi)
+		/*
+		 * We know that the caller doesn't actually need the
+		 * information below, so return early.
+		 */
+		return 0;
+	rtype = packed_object_info(r, e.p, e.offset, oi);
+	if (rtype < 0) {
+		mark_bad_packed_object(e.p, real);
+		return do_oid_object_info_extended(r, real, oi, 0);
+	} else if (oi->whence == OI_PACKED) {
+		oi->u.packed.offset = e.offset;
+		oi->u.packed.pack = e.p;
+		oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
+					 rtype == OBJ_OFS_DELTA);
+	}
+
+	return 0;
+}
+
+static int oid_object_info_convert(struct repository *r,
+				   const struct object_id *input_oid,
+				   struct object_info *input_oi, unsigned flags)
+{
+	const struct git_hash_algo *input_algo = &hash_algos[input_oid->algo];
+	int do_die = flags & OBJECT_INFO_DIE_IF_CORRUPT;
+	struct strbuf type_name = STRBUF_INIT;
+	struct object_id oid, delta_base_oid;
+	struct object_info new_oi, *oi;
+	unsigned long size;
+	void *content;
+	int ret;
+
+	if (repo_oid_to_algop(r, input_oid, the_hash_algo, &oid)) {
+		if (do_die)
+			die(_("missing mapping of %s to %s"),
+			    oid_to_hex(input_oid), the_hash_algo->name);
+		return -1;
+	}
+
+	/* Is new_oi needed? */
+	oi = input_oi;
+	if (input_oi && (input_oi->delta_base_oid || input_oi->sizep ||
+			 input_oi->contentp)) {
+		new_oi = *input_oi;
+		/* Does delta_base_oid need to be converted? */
+		if (input_oi->delta_base_oid)
+			new_oi.delta_base_oid = &delta_base_oid;
+		/* Will the attributes differ when converted? */
+		if (input_oi->sizep || input_oi->contentp) {
+			new_oi.contentp = &content;
+			new_oi.sizep = &size;
+			new_oi.type_name = &type_name;
+		}
+		oi = &new_oi;
+	}
+
+	ret = oid_object_info_extended(r, &oid, oi, flags);
+	if (ret)
+		return -1;
+	if (oi == input_oi)
+		return ret;
+
+	if (new_oi.contentp) {
+		struct strbuf outbuf = STRBUF_INIT;
+		enum object_type type;
+
+		type = type_from_string_gently(type_name.buf, type_name.len,
+					       !do_die);
+		if (type == -1)
+			return -1;
+		if (type != OBJ_BLOB) {
+			ret = convert_object_file(the_repository, &outbuf,
+						  the_hash_algo, input_algo,
+						  content, size, type, !do_die);
+			free(content);
+			if (ret == -1)
+				return -1;
+			size = outbuf.len;
+			content = strbuf_detach(&outbuf, NULL);
+		}
+		if (input_oi->sizep)
+			*input_oi->sizep = size;
+		if (input_oi->contentp)
+			*input_oi->contentp = content;
+		else
+			free(content);
+		if (input_oi->type_name)
+			*input_oi->type_name = type_name;
+		else
+			strbuf_release(&type_name);
+	}
+	if (new_oi.delta_base_oid == &delta_base_oid) {
+		if (repo_oid_to_algop(r, &delta_base_oid, input_algo,
+				 input_oi->delta_base_oid)) {
+			if (do_die)
+				die(_("missing mapping of %s to %s"),
+				    oid_to_hex(&delta_base_oid),
+				    input_algo->name);
+			return -1;
+		}
+	}
+	input_oi->whence = new_oi.whence;
+	input_oi->u = new_oi.u;
+	return ret;
+}
+
+int oid_object_info_extended(struct repository *r, const struct object_id *oid,
+			     struct object_info *oi, unsigned flags)
+{
+	int ret;
+
+	if (oid->algo && (hash_algo_by_ptr(r->hash_algo) != oid->algo))
+		return oid_object_info_convert(r, oid, oi, flags);
+
+	obj_read_lock();
+	ret = do_oid_object_info_extended(r, oid, oi, flags);
+	obj_read_unlock();
+	return ret;
+}
+
+
+/* returns enum object_type or negative */
+int oid_object_info(struct repository *r,
+		    const struct object_id *oid,
+		    unsigned long *sizep)
+{
+	enum object_type type;
+	struct object_info oi = OBJECT_INFO_INIT;
+
+	oi.typep = &type;
+	oi.sizep = sizep;
+	if (oid_object_info_extended(r, oid, &oi,
+				      OBJECT_INFO_LOOKUP_REPLACE) < 0)
+		return -1;
+	return type;
+}
+
+int pretend_object_file(struct repository *repo,
+			void *buf, unsigned long len, enum object_type type,
+			struct object_id *oid)
+{
+	struct cached_object_entry *co;
+	char *co_buf;
+
+	hash_object_file(repo->hash_algo, buf, len, type, oid);
+	if (repo_has_object_file_with_flags(repo, oid, OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT) ||
+	    find_cached_object(repo->objects, oid))
+		return 0;
+
+	ALLOC_GROW(repo->objects->cached_objects,
+		   repo->objects->cached_object_nr + 1, repo->objects->cached_object_alloc);
+	co = &repo->objects->cached_objects[repo->objects->cached_object_nr++];
+	co->value.size = len;
+	co->value.type = type;
+	co_buf = xmalloc(len);
+	memcpy(co_buf, buf, len);
+	co->value.buf = co_buf;
+	oidcpy(&co->oid, oid);
+	return 0;
+}
+
+/*
+ * This function dies on corrupt objects; the callers who want to
+ * deal with them should arrange to call oid_object_info_extended() and give
+ * error messages themselves.
+ */
+void *repo_read_object_file(struct repository *r,
+			    const struct object_id *oid,
+			    enum object_type *type,
+			    unsigned long *size)
+{
+	struct object_info oi = OBJECT_INFO_INIT;
+	unsigned flags = OBJECT_INFO_DIE_IF_CORRUPT | OBJECT_INFO_LOOKUP_REPLACE;
+	void *data;
+
+	oi.typep = type;
+	oi.sizep = size;
+	oi.contentp = &data;
+	if (oid_object_info_extended(r, oid, &oi, flags))
+		return NULL;
+
+	return data;
+}
+
+void *read_object_with_reference(struct repository *r,
+				 const struct object_id *oid,
+				 enum object_type required_type,
+				 unsigned long *size,
+				 struct object_id *actual_oid_return)
+{
+	enum object_type type;
+	void *buffer;
+	unsigned long isize;
+	struct object_id actual_oid;
+
+	oidcpy(&actual_oid, oid);
+	while (1) {
+		int ref_length = -1;
+		const char *ref_type = NULL;
+
+		buffer = repo_read_object_file(r, &actual_oid, &type, &isize);
+		if (!buffer)
+			return NULL;
+		if (type == required_type) {
+			*size = isize;
+			if (actual_oid_return)
+				oidcpy(actual_oid_return, &actual_oid);
+			return buffer;
+		}
+		/* Handle references */
+		else if (type == OBJ_COMMIT)
+			ref_type = "tree ";
+		else if (type == OBJ_TAG)
+			ref_type = "object ";
+		else {
+			free(buffer);
+			return NULL;
+		}
+		ref_length = strlen(ref_type);
+
+		if (ref_length + the_hash_algo->hexsz > isize ||
+		    memcmp(buffer, ref_type, ref_length) ||
+		    get_oid_hex((char *) buffer + ref_length, &actual_oid)) {
+			free(buffer);
+			return NULL;
+		}
+		free(buffer);
+		/* Now we have the ID of the referred-to object in
+		 * actual_oid.  Check again. */
+	}
+}
+
+int has_object(struct repository *r, const struct object_id *oid,
+	       unsigned flags)
+{
+	int quick = !(flags & HAS_OBJECT_RECHECK_PACKED);
+	unsigned object_info_flags = OBJECT_INFO_SKIP_FETCH_OBJECT |
+		(quick ? OBJECT_INFO_QUICK : 0);
+
+	if (!startup_info->have_repository)
+		return 0;
+	return oid_object_info_extended(r, oid, NULL, object_info_flags) >= 0;
+}
+
+int repo_has_object_file_with_flags(struct repository *r,
+				    const struct object_id *oid, int flags)
+{
+	if (!startup_info->have_repository)
+		return 0;
+	return oid_object_info_extended(r, oid, NULL, flags) >= 0;
+}
+
+int repo_has_object_file(struct repository *r,
+			 const struct object_id *oid)
+{
+	return repo_has_object_file_with_flags(r, oid, 0);
+}
+
+void assert_oid_type(const struct object_id *oid, enum object_type expect)
+{
+	enum object_type type = oid_object_info(the_repository, oid, NULL);
+	if (type < 0)
+		die(_("%s is not a valid object"), oid_to_hex(oid));
+	if (type != expect)
+		die(_("%s is not a valid '%s' object"), oid_to_hex(oid),
+		    type_name(expect));
+}
+
+struct raw_object_store *raw_object_store_new(void)
+{
+	struct raw_object_store *o = xmalloc(sizeof(*o));
+
+	memset(o, 0, sizeof(*o));
+	INIT_LIST_HEAD(&o->packed_git_mru);
+	hashmap_init(&o->pack_map, pack_map_entry_cmp, NULL, 0);
+	pthread_mutex_init(&o->replace_mutex, NULL);
+	return o;
+}
+
+static void free_object_directories(struct raw_object_store *o)
+{
+	while (o->odb) {
+		struct object_directory *next;
+
+		next = o->odb->next;
+		free_object_directory(o->odb);
+		o->odb = next;
+	}
+	kh_destroy_odb_path_map(o->odb_by_path);
+	o->odb_by_path = NULL;
+}
+
+void raw_object_store_clear(struct raw_object_store *o)
+{
+	FREE_AND_NULL(o->alternate_db);
+
+	oidmap_free(o->replace_map, 1);
+	FREE_AND_NULL(o->replace_map);
+	pthread_mutex_destroy(&o->replace_mutex);
+
+	free_commit_graph(o->commit_graph);
+	o->commit_graph = NULL;
+	o->commit_graph_attempted = 0;
+
+	free_object_directories(o);
+	o->odb_tail = NULL;
+	o->loaded_alternates = 0;
+
+	for (size_t i = 0; i < o->cached_object_nr; i++)
+		free((char *) o->cached_objects[i].value.buf);
+	FREE_AND_NULL(o->cached_objects);
+
+	INIT_LIST_HEAD(&o->packed_git_mru);
+	close_object_store(o);
+
+	/*
+	 * `close_object_store()` only closes the packfiles, but doesn't free
+	 * them. We thus have to do this manually.
+	 */
+	for (struct packed_git *p = o->packed_git, *next; p; p = next) {
+		next = p->next;
+		free(p);
+	}
+	o->packed_git = NULL;
+
+	hashmap_clear(&o->pack_map);
+}
diff --git a/object-store.h b/object-store.h
index 1b3e3d7d01..46961dc954 100644
--- a/object-store.h
+++ b/object-store.h
@@ -1,11 +1,517 @@
 #ifndef OBJECT_STORE_H
 #define OBJECT_STORE_H
 
-#include "khash.h"
-#include "dir.h"
-#include "object-store-ll.h"
+#include "hashmap.h"
+#include "object.h"
+#include "list.h"
+#include "oidset.h"
+#include "thread-utils.h"
 
-KHASH_INIT(odb_path_map, const char * /* key: odb_path */,
-	struct object_directory *, 1, fspathhash, fspatheq)
+struct oidmap;
+struct oidtree;
+struct strbuf;
+struct repository;
+
+struct object_directory {
+	struct object_directory *next;
+
+	/*
+	 * Used to store the results of readdir(3) calls when we are OK
+	 * sacrificing accuracy due to races for speed. That includes
+	 * object existence with OBJECT_INFO_QUICK, as well as
+	 * our search for unique abbreviated hashes. Don't use it for tasks
+	 * requiring greater accuracy!
+	 *
+	 * Be sure to call odb_load_loose_cache() before using.
+	 */
+	uint32_t loose_objects_subdir_seen[8]; /* 256 bits */
+	struct oidtree *loose_objects_cache;
+
+	/* Map between object IDs for loose objects. */
+	struct loose_object_map *loose_map;
+
+	/*
+	 * This is a temporary object store created by the tmp_objdir
+	 * facility. Disable ref updates since the objects in the store
+	 * might be discarded on rollback.
+	 */
+	int disable_ref_updates;
+
+	/*
+	 * This object store is ephemeral, so there is no need to fsync.
+	 */
+	int will_destroy;
+
+	/*
+	 * Path to the alternative object store. If this is a relative path,
+	 * it is relative to the current working directory.
+	 */
+	char *path;
+};
+
+void prepare_alt_odb(struct repository *r);
+int has_alt_odb(struct repository *r);
+char *compute_alternate_path(const char *path, struct strbuf *err);
+struct object_directory *find_odb(struct repository *r, const char *obj_dir);
+typedef int alt_odb_fn(struct object_directory *, void *);
+int foreach_alt_odb(alt_odb_fn, void*);
+typedef void alternate_ref_fn(const struct object_id *oid, void *);
+void for_each_alternate_ref(alternate_ref_fn, void *);
+
+/*
+ * Add the directory to the on-disk alternates file; the new entry will also
+ * take effect in the current process.
+ */
+void add_to_alternates_file(const char *dir);
+
+/*
+ * Add the directory to the in-memory list of alternates (along with any
+ * recursive alternates it points to), but do not modify the on-disk alternates
+ * file.
+ */
+void add_to_alternates_memory(const char *dir);
+
+/*
+ * Replace the current writable object directory with the specified temporary
+ * object directory; returns the former primary object directory.
+ */
+struct object_directory *set_temporary_primary_odb(const char *dir, int will_destroy);
+
+/*
+ * Restore a previous ODB replaced by set_temporary_main_odb.
+ */
+void restore_primary_odb(struct object_directory *restore_odb, const char *old_path);
+
+/*
+ * Populate and return the loose object cache array corresponding to the
+ * given object ID.
+ */
+struct oidtree *odb_loose_cache(struct object_directory *odb,
+				  const struct object_id *oid);
+
+/* Empty the loose object cache for the specified object directory. */
+void odb_clear_loose_cache(struct object_directory *odb);
+
+struct packed_git {
+	struct hashmap_entry packmap_ent;
+	struct packed_git *next;
+	struct list_head mru;
+	struct pack_window *windows;
+	off_t pack_size;
+	const void *index_data;
+	size_t index_size;
+	uint32_t num_objects;
+	size_t crc_offset;
+	struct oidset bad_objects;
+	int index_version;
+	time_t mtime;
+	int pack_fd;
+	int index;              /* for builtin/pack-objects.c */
+	unsigned pack_local:1,
+		 pack_keep:1,
+		 pack_keep_in_core:1,
+		 freshened:1,
+		 do_not_close:1,
+		 pack_promisor:1,
+		 multi_pack_index:1,
+		 is_cruft:1;
+	unsigned char hash[GIT_MAX_RAWSZ];
+	struct revindex_entry *revindex;
+	const uint32_t *revindex_data;
+	const uint32_t *revindex_map;
+	size_t revindex_size;
+	/*
+	 * mtimes_map points at the beginning of the memory mapped region of
+	 * this pack's corresponding .mtimes file, and mtimes_size is the size
+	 * of that .mtimes file
+	 */
+	const uint32_t *mtimes_map;
+	size_t mtimes_size;
+
+	/* repo denotes the repository this packfile belongs to */
+	struct repository *repo;
+
+	/* something like ".git/objects/pack/xxxxx.pack" */
+	char pack_name[FLEX_ARRAY]; /* more */
+};
+
+struct multi_pack_index;
+
+static inline int pack_map_entry_cmp(const void *cmp_data UNUSED,
+				     const struct hashmap_entry *entry,
+				     const struct hashmap_entry *entry2,
+				     const void *keydata)
+{
+	const char *key = keydata;
+	const struct packed_git *pg1, *pg2;
+
+	pg1 = container_of(entry, const struct packed_git, packmap_ent);
+	pg2 = container_of(entry2, const struct packed_git, packmap_ent);
+
+	return strcmp(pg1->pack_name, key ? key : pg2->pack_name);
+}
+
+struct cached_object_entry;
+
+struct raw_object_store {
+	/*
+	 * Set of all object directories; the main directory is first (and
+	 * cannot be NULL after initialization). Subsequent directories are
+	 * alternates.
+	 */
+	struct object_directory *odb;
+	struct object_directory **odb_tail;
+	struct kh_odb_path_map *odb_by_path;
+
+	int loaded_alternates;
+
+	/*
+	 * A list of alternate object directories loaded from the environment;
+	 * this should not generally need to be accessed directly, but will
+	 * populate the "odb" list when prepare_alt_odb() is run.
+	 */
+	char *alternate_db;
+
+	/*
+	 * Objects that should be substituted by other objects
+	 * (see git-replace(1)).
+	 */
+	struct oidmap *replace_map;
+	unsigned replace_map_initialized : 1;
+	pthread_mutex_t replace_mutex; /* protect object replace functions */
+
+	struct commit_graph *commit_graph;
+	unsigned commit_graph_attempted : 1; /* if loading has been attempted */
+
+	/*
+	 * private data
+	 *
+	 * should only be accessed directly by packfile.c and midx.c
+	 */
+	struct multi_pack_index *multi_pack_index;
+
+	/*
+	 * private data
+	 *
+	 * should only be accessed directly by packfile.c
+	 */
+
+	struct packed_git *packed_git;
+	/* A most-recently-used ordered version of the packed_git list. */
+	struct list_head packed_git_mru;
+
+	struct {
+		struct packed_git **packs;
+		unsigned flags;
+	} kept_pack_cache;
+
+	/*
+	 * This is meant to hold a *small* number of objects that you would
+	 * want repo_read_object_file() to be able to return, but yet you do not want
+	 * to write them into the object store (e.g. a browse-only
+	 * application).
+	 */
+	struct cached_object_entry *cached_objects;
+	size_t cached_object_nr, cached_object_alloc;
+
+	/*
+	 * A map of packfiles to packed_git structs for tracking which
+	 * packs have been loaded already.
+	 */
+	struct hashmap pack_map;
+
+	/*
+	 * A fast, rough count of the number of objects in the repository.
+	 * These two fields are not meant for direct access. Use
+	 * repo_approximate_object_count() instead.
+	 */
+	unsigned long approximate_object_count;
+	unsigned approximate_object_count_valid : 1;
+
+	/*
+	 * Whether packed_git has already been populated with this repository's
+	 * packs.
+	 */
+	unsigned packed_git_initialized : 1;
+};
+
+struct raw_object_store *raw_object_store_new(void);
+void raw_object_store_clear(struct raw_object_store *o);
+
+/*
+ * Create a temporary file rooted in the object database directory, or
+ * die on failure. The filename is taken from "pattern", which should have the
+ * usual "XXXXXX" trailer, and the resulting filename is written into the
+ * "template" buffer. Returns the open descriptor.
+ */
+int odb_mkstemp(struct strbuf *temp_filename, const char *pattern);
+
+/*
+ * Create a pack .keep file named "name" (which should generally be the output
+ * of odb_pack_name). Returns a file descriptor opened for writing, or -1 on
+ * error.
+ */
+int odb_pack_keep(const char *name);
+
+/*
+ * Put in `buf` the name of the file in the local object database that
+ * would be used to store a loose object with the specified oid.
+ */
+const char *loose_object_path(struct repository *r, struct strbuf *buf,
+			      const struct object_id *oid);
+
+void *map_loose_object(struct repository *r, const struct object_id *oid,
+		       unsigned long *size);
+
+void *repo_read_object_file(struct repository *r,
+			    const struct object_id *oid,
+			    enum object_type *type,
+			    unsigned long *size);
+
+/* Read and unpack an object file into memory, write memory to an object file */
+int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
+
+void hash_object_file(const struct git_hash_algo *algo, const void *buf,
+		      unsigned long len, enum object_type type,
+		      struct object_id *oid);
+
+/*
+ * Add an object file to the in-memory object store, without writing it
+ * to disk.
+ *
+ * Callers are responsible for calling write_object_file to record the
+ * object in persistent storage before writing any other new objects
+ * that reference it.
+ */
+int pretend_object_file(struct repository *repo,
+			void *buf, unsigned long len, enum object_type type,
+			struct object_id *oid);
+
+struct object_info {
+	/* Request */
+	enum object_type *typep;
+	unsigned long *sizep;
+	off_t *disk_sizep;
+	struct object_id *delta_base_oid;
+	struct strbuf *type_name;
+	void **contentp;
+
+	/* Response */
+	enum {
+		OI_CACHED,
+		OI_LOOSE,
+		OI_PACKED,
+		OI_DBCACHED
+	} whence;
+	union {
+		/*
+		 * struct {
+		 * 	... Nothing to expose in this case
+		 * } cached;
+		 * struct {
+		 * 	... Nothing to expose in this case
+		 * } loose;
+		 */
+		struct {
+			struct packed_git *pack;
+			off_t offset;
+			unsigned int is_delta;
+		} packed;
+	} u;
+};
+
+/*
+ * Initializer for a "struct object_info" that wants no items. You may
+ * also memset() the memory to all-zeroes.
+ */
+#define OBJECT_INFO_INIT { 0 }
+
+/* Invoke lookup_replace_object() on the given hash */
+#define OBJECT_INFO_LOOKUP_REPLACE 1
+/* Allow reading from a loose object file of unknown/bogus type */
+#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
+/* Do not retry packed storage after checking packed and loose storage */
+#define OBJECT_INFO_QUICK 8
+/*
+ * Do not attempt to fetch the object if missing (even if fetch_is_missing is
+ * nonzero).
+ */
+#define OBJECT_INFO_SKIP_FETCH_OBJECT 16
+/*
+ * This is meant for bulk prefetching of missing blobs in a partial
+ * clone. Implies OBJECT_INFO_SKIP_FETCH_OBJECT and OBJECT_INFO_QUICK
+ */
+#define OBJECT_INFO_FOR_PREFETCH (OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK)
+
+/* Die if object corruption (not just an object being missing) was detected. */
+#define OBJECT_INFO_DIE_IF_CORRUPT 32
+
+int oid_object_info_extended(struct repository *r,
+			     const struct object_id *,
+			     struct object_info *, unsigned flags);
+
+/* Retry packed storage after checking packed and loose storage */
+#define HAS_OBJECT_RECHECK_PACKED 1
+
+/*
+ * Returns 1 if the object exists. This function will not lazily fetch objects
+ * in a partial clone.
+ */
+int has_object(struct repository *r, const struct object_id *oid,
+	       unsigned flags);
+
+/*
+ * These macros and functions are deprecated. If checking existence for an
+ * object that is likely to be missing and/or whose absence is relatively
+ * inconsequential (or is consequential but the caller is prepared to handle
+ * it), use has_object(), which has better defaults (no lazy fetch in a partial
+ * clone and no rechecking of packed storage). In the unlikely event that a
+ * caller needs to assert existence of an object that it fully expects to
+ * exist, and wants to trigger a lazy fetch in a partial clone, use
+ * oid_object_info_extended() with a NULL struct object_info.
+ *
+ * These functions can be removed once all callers have migrated to
+ * has_object() and/or oid_object_info_extended().
+ */
+int repo_has_object_file(struct repository *r, const struct object_id *oid);
+int repo_has_object_file_with_flags(struct repository *r,
+				    const struct object_id *oid, int flags);
+
+void assert_oid_type(const struct object_id *oid, enum object_type expect);
+
+/*
+ * Enabling the object read lock allows multiple threads to safely call the
+ * following functions in parallel: repo_read_object_file(),
+ * read_object_with_reference(), oid_object_info() and oid_object_info_extended().
+ *
+ * obj_read_lock() and obj_read_unlock() may also be used to protect other
+ * section which cannot execute in parallel with object reading. Since the used
+ * lock is a recursive mutex, these sections can even contain calls to object
+ * reading functions. However, beware that in these cases zlib inflation won't
+ * be performed in parallel, losing performance.
+ *
+ * TODO: oid_object_info_extended()'s call stack has a recursive behavior. If
+ * any of its callees end up calling it, this recursive call won't benefit from
+ * parallel inflation.
+ */
+void enable_obj_read_lock(void);
+void disable_obj_read_lock(void);
+
+extern int obj_read_use_lock;
+extern pthread_mutex_t obj_read_mutex;
+
+static inline void obj_read_lock(void)
+{
+	if(obj_read_use_lock)
+		pthread_mutex_lock(&obj_read_mutex);
+}
+
+static inline void obj_read_unlock(void)
+{
+	if(obj_read_use_lock)
+		pthread_mutex_unlock(&obj_read_mutex);
+}
+
+/*
+ * Iterate over the files in the loose-object parts of the object
+ * directory "path", triggering the following callbacks:
+ *
+ *  - loose_object is called for each loose object we find.
+ *
+ *  - loose_cruft is called for any files that do not appear to be
+ *    loose objects. Note that we only look in the loose object
+ *    directories "objects/[0-9a-f]{2}/", so we will not report
+ *    "objects/foobar" as cruft.
+ *
+ *  - loose_subdir is called for each top-level hashed subdirectory
+ *    of the object directory (e.g., "$OBJDIR/f0"). It is called
+ *    after the objects in the directory are processed.
+ *
+ * Any callback that is NULL will be ignored. Callbacks returning non-zero
+ * will end the iteration.
+ *
+ * In the "buf" variant, "path" is a strbuf which will also be used as a
+ * scratch buffer, but restored to its original contents before
+ * the function returns.
+ */
+typedef int each_loose_object_fn(const struct object_id *oid,
+				 const char *path,
+				 void *data);
+typedef int each_loose_cruft_fn(const char *basename,
+				const char *path,
+				void *data);
+typedef int each_loose_subdir_fn(unsigned int nr,
+				 const char *path,
+				 void *data);
+int for_each_file_in_obj_subdir(unsigned int subdir_nr,
+				struct strbuf *path,
+				each_loose_object_fn obj_cb,
+				each_loose_cruft_fn cruft_cb,
+				each_loose_subdir_fn subdir_cb,
+				void *data);
+int for_each_loose_file_in_objdir(const char *path,
+				  each_loose_object_fn obj_cb,
+				  each_loose_cruft_fn cruft_cb,
+				  each_loose_subdir_fn subdir_cb,
+				  void *data);
+int for_each_loose_file_in_objdir_buf(struct strbuf *path,
+				      each_loose_object_fn obj_cb,
+				      each_loose_cruft_fn cruft_cb,
+				      each_loose_subdir_fn subdir_cb,
+				      void *data);
+
+/* Flags for for_each_*_object() below. */
+enum for_each_object_flags {
+	/* Iterate only over local objects, not alternates. */
+	FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
+
+	/* Only iterate over packs obtained from the promisor remote. */
+	FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
+
+	/*
+	 * Visit objects within a pack in packfile order rather than .idx order
+	 */
+	FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
+
+	/* Only iterate over packs that are not marked as kept in-core. */
+	FOR_EACH_OBJECT_SKIP_IN_CORE_KEPT_PACKS = (1<<3),
+
+	/* Only iterate over packs that do not have .keep files. */
+	FOR_EACH_OBJECT_SKIP_ON_DISK_KEPT_PACKS = (1<<4),
+};
+
+/*
+ * Iterate over all accessible loose objects without respect to
+ * reachability. By default, this includes both local and alternate objects.
+ * The order in which objects are visited is unspecified.
+ *
+ * Any flags specific to packs are ignored.
+ */
+int for_each_loose_object(each_loose_object_fn, void *,
+			  enum for_each_object_flags flags);
+
+/*
+ * Iterate over all accessible packed objects without respect to reachability.
+ * By default, this includes both local and alternate packs.
+ *
+ * Note that some objects may appear twice if they are found in multiple packs.
+ * Each pack is visited in an unspecified order. By default, objects within a
+ * pack are visited in pack-idx order (i.e., sorted by oid).
+ */
+typedef int each_packed_object_fn(const struct object_id *oid,
+				  struct packed_git *pack,
+				  uint32_t pos,
+				  void *data);
+int for_each_object_in_pack(struct packed_git *p,
+			    each_packed_object_fn, void *data,
+			    enum for_each_object_flags flags);
+int for_each_packed_object(struct repository *repo, each_packed_object_fn cb,
+			   void *data, enum for_each_object_flags flags);
+
+void *read_object_with_reference(struct repository *r,
+				 const struct object_id *oid,
+				 enum object_type required_type,
+				 unsigned long *size,
+				 struct object_id *oid_ret);
 
 #endif /* OBJECT_STORE_H */
diff --git a/object.c b/object.c
index d054e7f0d0..3b15469139 100644
--- a/object.c
+++ b/object.c
@@ -6,16 +6,13 @@
 #include "object.h"
 #include "replace-object.h"
 #include "object-file.h"
-#include "object-store.h"
 #include "blob.h"
 #include "statinfo.h"
 #include "tree.h"
 #include "commit.h"
 #include "tag.h"
 #include "alloc.h"
-#include "packfile.h"
 #include "commit-graph.h"
-#include "loose.h"
 
 unsigned int get_max_object_index(const struct repository *repo)
 {
@@ -534,70 +531,6 @@ struct parsed_object_pool *parsed_object_pool_new(struct repository *repo)
 	return o;
 }
 
-struct raw_object_store *raw_object_store_new(void)
-{
-	struct raw_object_store *o = xmalloc(sizeof(*o));
-
-	memset(o, 0, sizeof(*o));
-	INIT_LIST_HEAD(&o->packed_git_mru);
-	hashmap_init(&o->pack_map, pack_map_entry_cmp, NULL, 0);
-	pthread_mutex_init(&o->replace_mutex, NULL);
-	return o;
-}
-
-void free_object_directory(struct object_directory *odb)
-{
-	free(odb->path);
-	odb_clear_loose_cache(odb);
-	loose_object_map_clear(&odb->loose_map);
-	free(odb);
-}
-
-static void free_object_directories(struct raw_object_store *o)
-{
-	while (o->odb) {
-		struct object_directory *next;
-
-		next = o->odb->next;
-		free_object_directory(o->odb);
-		o->odb = next;
-	}
-	kh_destroy_odb_path_map(o->odb_by_path);
-	o->odb_by_path = NULL;
-}
-
-void raw_object_store_clear(struct raw_object_store *o)
-{
-	FREE_AND_NULL(o->alternate_db);
-
-	oidmap_free(o->replace_map, 1);
-	FREE_AND_NULL(o->replace_map);
-	pthread_mutex_destroy(&o->replace_mutex);
-
-	free_commit_graph(o->commit_graph);
-	o->commit_graph = NULL;
-	o->commit_graph_attempted = 0;
-
-	free_object_directories(o);
-	o->odb_tail = NULL;
-	o->loaded_alternates = 0;
-
-	INIT_LIST_HEAD(&o->packed_git_mru);
-	close_object_store(o);
-
-	/*
-	 * `close_object_store()` only closes the packfiles, but doesn't free
-	 * them. We thus have to do this manually.
-	 */
-	for (struct packed_git *p = o->packed_git, *next; p; p = next) {
-		next = p->next;
-		free(p);
-	}
-	o->packed_git = NULL;
-
-	hashmap_clear(&o->pack_map);
-}
-
 void parsed_object_pool_reset_commit_grafts(struct parsed_object_pool *o)
 {
 	for (int i = 0; i < o->grafts_nr; i++) {
diff --git a/oss-fuzz/fuzz-pack-idx.c b/oss-fuzz/fuzz-pack-idx.c
index 3e190214d1..609a343ee3 100644
--- a/oss-fuzz/fuzz-pack-idx.c
+++ b/oss-fuzz/fuzz-pack-idx.c
@@ -1,5 +1,5 @@
 #include "git-compat-util.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c
index 02051c6e71..7f400ee012 100644
--- a/pack-bitmap-write.c
+++ b/pack-bitmap-write.c
@@ -4,7 +4,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "diff.h"
 #include "revision.h"
diff --git a/pack-bitmap.c b/pack-bitmap.c
index 5299f49d59..b9f1d86604 100644
--- a/pack-bitmap.c
+++ b/pack-bitmap.c
@@ -17,8 +17,7 @@
 #include "packfile.h"
 #include "repository.h"
 #include "trace2.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "list-objects-filter-options.h"
 #include "midx.h"
 #include "config.h"
diff --git a/pack-check.c b/pack-check.c
index 95dcbbe985..874897d6cb 100644
--- a/pack-check.c
+++ b/pack-check.c
@@ -8,7 +8,7 @@
 #include "progress.h"
 #include "packfile.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 struct idx_entry {
 	off_t                offset;
diff --git a/pack-mtimes.c b/pack-mtimes.c
index cdf30b8d2b..20900ca88d 100644
--- a/pack-mtimes.c
+++ b/pack-mtimes.c
@@ -1,8 +1,7 @@
 #include "git-compat-util.h"
 #include "gettext.h"
 #include "pack-mtimes.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "strbuf.h"
 
diff --git a/pack-objects.h b/pack-objects.h
index d73e3843c9..d1c4ae7f9b 100644
--- a/pack-objects.h
+++ b/pack-objects.h
@@ -1,7 +1,7 @@
 #ifndef PACK_OBJECTS_H
 #define PACK_OBJECTS_H
 
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "thread-utils.h"
 #include "pack.h"
 
diff --git a/pack-revindex.c b/pack-revindex.c
index f035a33a5a..ffcde48870 100644
--- a/pack-revindex.c
+++ b/pack-revindex.c
@@ -1,8 +1,7 @@
 #include "git-compat-util.h"
 #include "gettext.h"
 #include "pack-revindex.h"
-#include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "strbuf.h"
 #include "trace2.h"
diff --git a/packfile.c b/packfile.c
index 9d09f8bc72..d91016f1c7 100644
--- a/packfile.c
+++ b/packfile.c
@@ -19,7 +19,7 @@
 #include "tree-walk.h"
 #include "tree.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "midx.h"
 #include "commit-graph.h"
 #include "pack-revindex.h"
diff --git a/path.c b/path.c
index 910756c8b3..4505bb78e8 100644
--- a/path.c
+++ b/path.c
@@ -15,7 +15,7 @@
 #include "submodule-config.h"
 #include "path.h"
 #include "packfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "lockfile.h"
 #include "exec-cmd.h"
 
@@ -902,6 +902,115 @@ void safe_create_dir(struct repository *repo, const char *dir, int share)
 		die(_("Could not make %s writable by group"), dir);
 }
 
+int safe_create_dir_in_gitdir(struct repository *repo, const char *path)
+{
+	if (mkdir(path, 0777)) {
+		int saved_errno = errno;
+		struct stat st;
+		struct strbuf sb = STRBUF_INIT;
+
+		if (errno != EEXIST)
+			return -1;
+		/*
+		 * Are we looking at a path in a symlinked worktree
+		 * whose original repository does not yet have it?
+		 * e.g. .git/rr-cache pointing at its original
+		 * repository in which the user hasn't performed any
+		 * conflict resolution yet?
+		 */
+		if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
+		    strbuf_readlink(&sb, path, st.st_size) ||
+		    !is_absolute_path(sb.buf) ||
+		    mkdir(sb.buf, 0777)) {
+			strbuf_release(&sb);
+			errno = saved_errno;
+			return -1;
+		}
+		strbuf_release(&sb);
+	}
+	return adjust_shared_perm(repo, path);
+}
+
+static enum scld_error safe_create_leading_directories_1(struct repository *repo,
+							 char *path)
+{
+	char *next_component = path + offset_1st_component(path);
+	enum scld_error ret = SCLD_OK;
+
+	while (ret == SCLD_OK && next_component) {
+		struct stat st;
+		char *slash = next_component, slash_character;
+
+		while (*slash && !is_dir_sep(*slash))
+			slash++;
+
+		if (!*slash)
+			break;
+
+		next_component = slash + 1;
+		while (is_dir_sep(*next_component))
+			next_component++;
+		if (!*next_component)
+			break;
+
+		slash_character = *slash;
+		*slash = '\0';
+		if (!stat(path, &st)) {
+			/* path exists */
+			if (!S_ISDIR(st.st_mode)) {
+				errno = ENOTDIR;
+				ret = SCLD_EXISTS;
+			}
+		} else if (mkdir(path, 0777)) {
+			if (errno == EEXIST &&
+			    !stat(path, &st) && S_ISDIR(st.st_mode))
+				; /* somebody created it since we checked */
+			else if (errno == ENOENT)
+				/*
+				 * Either mkdir() failed because
+				 * somebody just pruned the containing
+				 * directory, or stat() failed because
+				 * the file that was in our way was
+				 * just removed.  Either way, inform
+				 * the caller that it might be worth
+				 * trying again:
+				 */
+				ret = SCLD_VANISHED;
+			else
+				ret = SCLD_FAILED;
+		} else if (repo && adjust_shared_perm(repo, path)) {
+			ret = SCLD_PERMS;
+		}
+		*slash = slash_character;
+	}
+	return ret;
+}
+
+enum scld_error safe_create_leading_directories(struct repository *repo,
+						char *path)
+{
+	return safe_create_leading_directories_1(repo, path);
+}
+
+enum scld_error safe_create_leading_directories_no_share(char *path)
+{
+	return safe_create_leading_directories_1(NULL, path);
+}
+
+enum scld_error safe_create_leading_directories_const(struct repository *repo,
+						      const char *path)
+{
+	int save_errno;
+	/* path points to cache entries, so xstrdup before messing with it */
+	char *buf = xstrdup(path);
+	enum scld_error result = safe_create_leading_directories(repo, buf);
+
+	save_errno = errno;
+	free(buf);
+	errno = save_errno;
+	return result;
+}
+
 static int have_same_root(const char *path1, const char *path2)
 {
 	int is_abs1, is_abs2;
diff --git a/path.h b/path.h
index 65fe968a13..fd1a194b06 100644
--- a/path.h
+++ b/path.h
@@ -221,6 +221,51 @@ char *xdg_cache_home(const char *filename);
  */
 void safe_create_dir(struct repository *repo, const char *dir, int share);
 
+/*
+ * Similar to `safe_create_dir()`, but with two differences:
+ *
+ *   - It knows to resolve gitlink files for symlinked worktrees.
+ *
+ *   - It always adjusts shared permissions.
+ *
+ * Returns a negative erorr code on error, 0 on success.
+ */
+int safe_create_dir_in_gitdir(struct repository *repo, const char *path);
+
+/*
+ * Create the directory containing the named path, using care to be
+ * somewhat safe against races. Return one of the scld_error values to
+ * indicate success/failure. On error, set errno to describe the
+ * problem.
+ *
+ * SCLD_VANISHED indicates that one of the ancestor directories of the
+ * path existed at one point during the function call and then
+ * suddenly vanished, probably because another process pruned the
+ * directory while we were working.  To be robust against this kind of
+ * race, callers might want to try invoking the function again when it
+ * returns SCLD_VANISHED.
+ *
+ * safe_create_leading_directories() temporarily changes path while it
+ * is working but restores it before returning.
+ * safe_create_leading_directories_const() doesn't modify path, even
+ * temporarily. Both these variants adjust the permissions of the
+ * created directories to honor core.sharedRepository, so they are best
+ * suited for files inside the git dir. For working tree files, use
+ * safe_create_leading_directories_no_share() instead, as it ignores
+ * the core.sharedRepository setting.
+ */
+enum scld_error {
+	SCLD_OK = 0,
+	SCLD_FAILED = -1,
+	SCLD_PERMS = -2,
+	SCLD_EXISTS = -3,
+	SCLD_VANISHED = -4
+};
+enum scld_error safe_create_leading_directories(struct repository *repo, char *path);
+enum scld_error safe_create_leading_directories_const(struct repository *repo,
+						      const char *path);
+enum scld_error safe_create_leading_directories_no_share(char *path);
+
 # ifdef USE_THE_REPOSITORY_VARIABLE
 #  include "strbuf.h"
 #  include "repository.h"
diff --git a/promisor-remote.c b/promisor-remote.c
index 5801ebfd9b..9d058586df 100644
--- a/promisor-remote.c
+++ b/promisor-remote.c
@@ -3,7 +3,7 @@
 #include "git-compat-util.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "promisor-remote.h"
 #include "config.h"
 #include "trace2.h"
diff --git a/protocol-caps.c b/protocol-caps.c
index 855f279c2f..9b8db37a21 100644
--- a/protocol-caps.c
+++ b/protocol-caps.c
@@ -6,7 +6,7 @@
 #include "hash.h"
 #include "hex.h"
 #include "object.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "repository.h"
 #include "string-list.h"
 #include "strbuf.h"
diff --git a/prune-packed.c b/prune-packed.c
index 7dad2fc0c1..c1d95a519d 100644
--- a/prune-packed.c
+++ b/prune-packed.c
@@ -2,7 +2,7 @@
 
 #include "git-compat-util.h"
 #include "gettext.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "progress.h"
 #include "prune-packed.h"
diff --git a/reachable.c b/reachable.c
index 299e129249..e5f56f4018 100644
--- a/reachable.c
+++ b/reachable.c
@@ -14,7 +14,7 @@
 #include "list-objects.h"
 #include "packfile.h"
 #include "worktree.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pack-bitmap.h"
 #include "pack-mtimes.h"
 #include "config.h"
diff --git a/read-cache.c b/read-cache.c
index 4cdc7bb661..73f83a7e7a 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -20,7 +20,7 @@
 #include "refs.h"
 #include "dir.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "tree.h"
 #include "commit.h"
@@ -706,11 +706,11 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 	int intent_only = flags & ADD_CACHE_INTENT;
 	int add_option = (ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE|
 			  (intent_only ? ADD_CACHE_NEW_ONLY : 0));
-	unsigned hash_flags = pretend ? 0 : HASH_WRITE_OBJECT;
+	unsigned hash_flags = pretend ? 0 : INDEX_WRITE_OBJECT;
 	struct object_id oid;
 
 	if (flags & ADD_CACHE_RENORMALIZE)
-		hash_flags |= HASH_RENORMALIZE;
+		hash_flags |= INDEX_RENORMALIZE;
 
 	if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
 		return error(_("%s: can only add regular files, symbolic links or git-directories"), path);
diff --git a/ref-filter.c b/ref-filter.c
index 6da8d4c03b..7a274633cf 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -12,7 +12,7 @@
 #include "refs.h"
 #include "wildmatch.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "repo-settings.h"
 #include "repository.h"
diff --git a/reflog.c b/reflog.c
index 642b162ef7..12f7a02e34 100644
--- a/reflog.c
+++ b/reflog.c
@@ -4,8 +4,8 @@
 #include "git-compat-util.h"
 #include "config.h"
 #include "gettext.h"
-#include "object-store-ll.h"
 #include "parse-options.h"
+#include "object-store.h"
 #include "reflog.h"
 #include "refs.h"
 #include "revision.h"
diff --git a/refs.c b/refs.c
index 6720c3da28..6559db3789 100644
--- a/refs.c
+++ b/refs.c
@@ -19,7 +19,7 @@
 #include "run-command.h"
 #include "hook.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "object.h"
 #include "path.h"
 #include "submodule.h"
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 5057dd02ed..4d1f65a57a 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -708,7 +708,7 @@ static enum ref_transaction_error lock_raw_ref(struct files_ref_store *refs,
 	files_ref_path(refs, &ref_file, refname);
 
 retry:
-	switch (safe_create_leading_directories(ref_file.buf)) {
+	switch (safe_create_leading_directories(the_repository, ref_file.buf)) {
 	case SCLD_OK:
 		break; /* success */
 	case SCLD_EXISTS:
@@ -1119,7 +1119,7 @@ retry_fn:
 			strbuf_addstr(&path_copy, path);
 
 		do {
-			scld_result = safe_create_leading_directories(path_copy.buf);
+			scld_result = safe_create_leading_directories(the_repository, path_copy.buf);
 			if (scld_result == SCLD_OK)
 				goto retry_fn;
 		} while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
diff --git a/remote.c b/remote.c
index e7e10c7f4b..9fa3614e7a 100644
--- a/remote.c
+++ b/remote.c
@@ -12,7 +12,7 @@
 #include "refs.h"
 #include "refspec.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "commit.h"
 #include "diff.h"
diff --git a/replace-object.c b/replace-object.c
index 9a3cdd809a..7b8a09b5cb 100644
--- a/replace-object.c
+++ b/replace-object.c
@@ -2,7 +2,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "oidmap.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "refs.h"
 #include "repository.h"
diff --git a/replace-object.h b/replace-object.h
index 66c41b938b..ba478eb30c 100644
--- a/replace-object.h
+++ b/replace-object.h
@@ -3,7 +3,7 @@
 
 #include "oidmap.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 
 struct replace_object {
 	struct oidmap_entry original;
diff --git a/repository.c b/repository.c
index 6cbaf2e3da..9b3d6665fc 100644
--- a/repository.c
+++ b/repository.c
@@ -1,7 +1,7 @@
 #include "git-compat-util.h"
 #include "abspath.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "config.h"
 #include "object.h"
 #include "lockfile.h"
diff --git a/rerere.c b/rerere.c
index 740e8ad1a0..3cd37c5f0a 100644
--- a/rerere.c
+++ b/rerere.c
@@ -18,7 +18,7 @@
 #include "path.h"
 #include "pathspec.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strmap.h"
 
 #define RESOLVED 0
@@ -860,7 +860,7 @@ static int do_plain_rerere(struct repository *r,
 		string_list_insert(rr, path)->util = id;
 
 		/* Ensure that the directory exists. */
-		mkdir_in_gitdir(rerere_path(&buf, id, NULL));
+		safe_create_dir_in_gitdir(the_repository, rerere_path(&buf, id, NULL));
 	}
 
 	for (i = 0; i < rr->nr; i++)
@@ -895,7 +895,8 @@ static int is_rerere_enabled(void)
 	if (rerere_enabled < 0)
 		return rr_cache_exists;
 
-	if (!rr_cache_exists && mkdir_in_gitdir(git_path_rr_cache()))
+	if (!rr_cache_exists &&
+	    safe_create_dir_in_gitdir(the_repository, git_path_rr_cache()))
 		die(_("could not create directory '%s'"), git_path_rr_cache());
 	return 1;
 }
diff --git a/revision.c b/revision.c
index 550453ab70..2c36a9c179 100644
--- a/revision.c
+++ b/revision.c
@@ -8,7 +8,7 @@
 #include "hex.h"
 #include "object-name.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oidset.h"
 #include "tag.h"
 #include "blob.h"
diff --git a/send-pack.c b/send-pack.c
index 856a65d5f5..5005689cb5 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -4,7 +4,7 @@
 #include "date.h"
 #include "gettext.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pkt-line.h"
 #include "sideband.h"
 #include "run-command.h"
diff --git a/sequencer.c b/sequencer.c
index 9ea678364d..b5c4043757 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -13,7 +13,7 @@
 #include "dir.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "object.h"
 #include "pager.h"
 #include "commit.h"
@@ -4395,7 +4395,7 @@ static int write_update_refs_state(struct string_list *refs_to_oids)
 		goto cleanup;
 	}
 
-	if (safe_create_leading_directories(path)) {
+	if (safe_create_leading_directories(the_repository, path)) {
 		result = error(_("unable to create leading directories of %s"),
 			       path);
 		goto cleanup;
@@ -4661,7 +4661,7 @@ static void create_autostash_internal(struct repository *r,
 		strbuf_add_unique_abbrev(&buf, &oid, DEFAULT_ABBREV);
 
 		if (path) {
-			if (safe_create_leading_directories_const(path))
+			if (safe_create_leading_directories_const(the_repository, path))
 				die(_("Could not create directory for '%s'"),
 				    path);
 			write_file(path, "%s", oid_to_hex(&oid));
diff --git a/server-info.c b/server-info.c
index 1ca0e00d51..d6cd20a39d 100644
--- a/server-info.c
+++ b/server-info.c
@@ -11,7 +11,7 @@
 #include "packfile.h"
 #include "path.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "server-info.h"
 #include "strbuf.h"
 #include "tempfile.h"
@@ -88,7 +88,7 @@ static int update_info_file(struct repository *r, char *path,
 		.old_sb = STRBUF_INIT
 	};
 
-	safe_create_leading_directories(path);
+	safe_create_leading_directories(r, path);
 	f = mks_tempfile_m(tmp, 0666);
 	if (!f)
 		goto out;
diff --git a/shallow.c b/shallow.c
index 06c3266a3e..2f82ebd6e3 100644
--- a/shallow.c
+++ b/shallow.c
@@ -5,7 +5,7 @@
 #include "repository.h"
 #include "tempfile.h"
 #include "lockfile.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "tag.h"
 #include "pkt-line.h"
diff --git a/streaming.c b/streaming.c
index 018b794d25..127d6b5d6a 100644
--- a/streaming.c
+++ b/streaming.c
@@ -10,7 +10,7 @@
 #include "streaming.h"
 #include "repository.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "replace-object.h"
 #include "packfile.h"
 
diff --git a/submodule-config.c b/submodule-config.c
index d82b404b73..8630e27947 100644
--- a/submodule-config.c
+++ b/submodule-config.c
@@ -13,7 +13,7 @@
 #include "submodule.h"
 #include "strbuf.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "parse-options.h"
 #include "thread-utils.h"
 #include "tree-walk.h"
diff --git a/submodule.c b/submodule.c
index 0821507eca..ead3fb5dad 100644
--- a/submodule.c
+++ b/submodule.c
@@ -27,7 +27,7 @@
 #include "parse-options.h"
 #include "object-file.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit-reach.h"
 #include "read-cache-ll.h"
 #include "setup.h"
@@ -2384,7 +2384,7 @@ static void relocate_single_git_dir_into_superproject(const char *path,
 	if (validate_submodule_git_dir(new_gitdir.buf, sub->name) < 0)
 		die(_("refusing to move '%s' into an existing git dir"),
 		    real_old_git_dir);
-	if (safe_create_leading_directories_const(new_gitdir.buf) < 0)
+	if (safe_create_leading_directories_const(the_repository, new_gitdir.buf) < 0)
 		die(_("could not create directory '%s'"), new_gitdir.buf);
 	real_new_git_dir = real_pathdup(new_gitdir.buf, 1);
 
diff --git a/t/helper/test-pack-mtimes.c b/t/helper/test-pack-mtimes.c
index f8f9afbb5b..50f5941bff 100644
--- a/t/helper/test-pack-mtimes.c
+++ b/t/helper/test-pack-mtimes.c
@@ -3,7 +3,7 @@
 #include "test-tool.h"
 #include "hex.h"
 #include "strbuf.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "packfile.h"
 #include "pack-mtimes.h"
 #include "setup.h"
diff --git a/t/helper/test-partial-clone.c b/t/helper/test-partial-clone.c
index a1af9710c3..34f1aee558 100644
--- a/t/helper/test-partial-clone.c
+++ b/t/helper/test-partial-clone.c
@@ -1,7 +1,7 @@
 #include "test-tool.h"
 #include "hex.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "setup.h"
 
 /*
diff --git a/t/helper/test-read-graph.c b/t/helper/test-read-graph.c
index 811dde1cb3..8b413b644b 100644
--- a/t/helper/test-read-graph.c
+++ b/t/helper/test-read-graph.c
@@ -3,7 +3,7 @@
 #include "test-tool.h"
 #include "commit-graph.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "bloom.h"
 #include "setup.h"
 
diff --git a/t/helper/test-read-midx.c b/t/helper/test-read-midx.c
index fc63236961..ac81390899 100644
--- a/t/helper/test-read-midx.c
+++ b/t/helper/test-read-midx.c
@@ -4,7 +4,7 @@
 #include "hex.h"
 #include "midx.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "pack-bitmap.h"
 #include "packfile.h"
 #include "setup.h"
diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c
index 2ff67c067a..4cfc7c90b5 100644
--- a/t/helper/test-ref-store.c
+++ b/t/helper/test-ref-store.c
@@ -5,7 +5,7 @@
 #include "refs.h"
 #include "setup.h"
 #include "worktree.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "path.h"
 #include "repository.h"
 #include "strbuf.h"
diff --git a/tag.c b/tag.c
index 8d9e9e2930..05be39067c 100644
--- a/tag.c
+++ b/tag.c
@@ -5,7 +5,7 @@
 #include "environment.h"
 #include "tag.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "tree.h"
 #include "blob.h"
diff --git a/tmp-objdir.c b/tmp-objdir.c
index 31d16a4c2c..c38fbeb5e8 100644
--- a/tmp-objdir.c
+++ b/tmp-objdir.c
@@ -10,7 +10,7 @@
 #include "strbuf.h"
 #include "strvec.h"
 #include "quote.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "repository.h"
 
 struct tmp_objdir {
diff --git a/tree-walk.c b/tree-walk.c
index a033397965..90655d5237 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -6,7 +6,7 @@
 #include "gettext.h"
 #include "hex.h"
 #include "object-file.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "trace2.h"
 #include "tree.h"
 #include "pathspec.h"
diff --git a/tree.c b/tree.c
index ad86ad1ba9..b85f56267f 100644
--- a/tree.c
+++ b/tree.c
@@ -4,7 +4,7 @@
 #include "hex.h"
 #include "tree.h"
 #include "object-name.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "alloc.h"
 #include "tree-walk.h"
diff --git a/unpack-trees.c b/unpack-trees.c
index cf5b73c84b..471837f032 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -26,7 +26,7 @@
 #include "symlinks.h"
 #include "trace2.h"
 #include "fsmonitor.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "promisor-remote.h"
 #include "entry.h"
 #include "parallel-checkout.h"
diff --git a/upload-pack.c b/upload-pack.c
index 02ce633602..30e4630f3a 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -10,7 +10,7 @@
 #include "pkt-line.h"
 #include "sideband.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "oid-array.h"
 #include "object.h"
 #include "commit.h"
diff --git a/walker.c b/walker.c
index 1cf3da0219..4fedc19f34 100644
--- a/walker.c
+++ b/walker.c
@@ -5,7 +5,7 @@
 #include "hex.h"
 #include "walker.h"
 #include "repository.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "commit.h"
 #include "strbuf.h"
 #include "tree.h"
diff --git a/wrapper.c b/wrapper.c
index 8b98593149..3c79778055 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -829,3 +829,51 @@ uint32_t git_rand(unsigned flags)
 
 	return result;
 }
+
+static void mmap_limit_check(size_t length)
+{
+	static size_t limit = 0;
+	if (!limit) {
+		limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
+		if (!limit)
+			limit = SIZE_MAX;
+	}
+	if (length > limit)
+		die(_("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX),
+		    (uintmax_t)length, (uintmax_t)limit);
+}
+
+void *xmmap_gently(void *start, size_t length,
+		  int prot, int flags, int fd, off_t offset)
+{
+	void *ret;
+
+	mmap_limit_check(length);
+	ret = mmap(start, length, prot, flags, fd, offset);
+	if (ret == MAP_FAILED && !length)
+		ret = NULL;
+	return ret;
+}
+
+const char *mmap_os_err(void)
+{
+	static const char blank[] = "";
+#if defined(__linux__)
+	if (errno == ENOMEM) {
+		/* this continues an existing error message: */
+		static const char enomem[] =
+", check sys.vm.max_map_count and/or RLIMIT_DATA";
+		return enomem;
+	}
+#endif /* OS-specific bits */
+	return blank;
+}
+
+void *xmmap(void *start, size_t length,
+	int prot, int flags, int fd, off_t offset)
+{
+	void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
+	if (ret == MAP_FAILED)
+		die_errno(_("mmap failed%s"), mmap_os_err());
+	return ret;
+}
diff --git a/xdiff-interface.c b/xdiff-interface.c
index 77712811ff..1edcd319e6 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -5,7 +5,7 @@
 #include "gettext.h"
 #include "config.h"
 #include "hex.h"
-#include "object-store-ll.h"
+#include "object-store.h"
 #include "strbuf.h"
 #include "xdiff-interface.h"
 #include "xdiff/xtypes.h"