diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index fb91833e76..1da44a3d6d 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -517,6 +517,32 @@ static int refname_contains_nul(struct strbuf *refname)
 
 #define SMALL_FILE_SIZE (32*1024)
 
+static int allocate_snapshot_buffer(struct snapshot *snapshot, int fd, struct stat *st)
+{
+	ssize_t bytes_read;
+	size_t size;
+
+	size = xsize_t(st->st_size);
+	if (!size)
+		return 0;
+
+	if (mmap_strategy == MMAP_NONE || size <= SMALL_FILE_SIZE) {
+		snapshot->buf = xmalloc(size);
+		bytes_read = read_in_full(fd, snapshot->buf, size);
+		if (bytes_read < 0 || bytes_read != size)
+			die_errno("couldn't read %s", snapshot->refs->path);
+		snapshot->mmapped = 0;
+	} else {
+		snapshot->buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+		snapshot->mmapped = 1;
+	}
+
+	snapshot->start = snapshot->buf;
+	snapshot->eof = snapshot->buf + size;
+
+	return 1;
+}
+
 /*
  * Depending on `mmap_strategy`, either mmap or read the contents of
  * the `packed-refs` file into the snapshot. Return 1 if the file
@@ -525,10 +551,9 @@ static int refname_contains_nul(struct strbuf *refname)
  */
 static int load_contents(struct snapshot *snapshot)
 {
-	int fd;
 	struct stat st;
-	size_t size;
-	ssize_t bytes_read;
+	int ret;
+	int fd;
 
 	fd = open(snapshot->refs->path, O_RDONLY);
 	if (fd < 0) {
@@ -550,27 +575,11 @@ static int load_contents(struct snapshot *snapshot)
 
 	if (fstat(fd, &st) < 0)
 		die_errno("couldn't stat %s", snapshot->refs->path);
-	size = xsize_t(st.st_size);
 
-	if (!size) {
-		close(fd);
-		return 0;
-	} else if (mmap_strategy == MMAP_NONE || size <= SMALL_FILE_SIZE) {
-		snapshot->buf = xmalloc(size);
-		bytes_read = read_in_full(fd, snapshot->buf, size);
-		if (bytes_read < 0 || bytes_read != size)
-			die_errno("couldn't read %s", snapshot->refs->path);
-		snapshot->mmapped = 0;
-	} else {
-		snapshot->buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
-		snapshot->mmapped = 1;
-	}
+	ret = allocate_snapshot_buffer(snapshot, fd, &st);
+
 	close(fd);
-
-	snapshot->start = snapshot->buf;
-	snapshot->eof = snapshot->buf + size;
-
-	return 1;
+	return ret;
 }
 
 static const char *find_reference_location_1(struct snapshot *snapshot,