diff --git a/apply.c b/apply.c
index 6212ab3a1b..3da33bb88f 100644
--- a/apply.c
+++ b/apply.c
@@ -23,6 +23,7 @@
 #include "xdiff-interface.h"
 #include "ll-merge.h"
 #include "lockfile.h"
+#include "name-hash.h"
 #include "object-name.h"
 #include "object-file.h"
 #include "parse-options.h"
diff --git a/builtin/mv.c b/builtin/mv.c
index 665bd27448..e058b57465 100644
--- a/builtin/mv.c
+++ b/builtin/mv.c
@@ -11,6 +11,7 @@
 #include "config.h"
 #include "environment.h"
 #include "gettext.h"
+#include "name-hash.h"
 #include "object-file.h"
 #include "pathspec.h"
 #include "lockfile.h"
diff --git a/cache.h b/cache.h
index d31b151506..316904da39 100644
--- a/cache.h
+++ b/cache.h
@@ -245,12 +245,6 @@ struct index_state {
 void index_state_init(struct index_state *istate, struct repository *r);
 void release_index(struct index_state *istate);
 
-/* Name hashing */
-int test_lazy_init_name_hash(struct index_state *istate, int try_threaded);
-void add_name_hash(struct index_state *istate, struct cache_entry *ce);
-void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
-void free_name_hash(struct index_state *istate);
-
 /* Cache entry creation and cleanup */
 
 /*
@@ -377,9 +371,6 @@ int repo_index_has_changes(struct repository *repo,
 
 int verify_path(const char *path, unsigned mode);
 int strcmp_offset(const char *s1, const char *s2, size_t *first_change);
-int index_dir_exists(struct index_state *istate, const char *name, int namelen);
-void adjust_dirname_case(struct index_state *istate, char *name);
-struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
 
 /*
  * Searches for an entry defined by name and namelen in the given index.
diff --git a/dir.c b/dir.c
index a7469df3ac..029aab36fe 100644
--- a/dir.c
+++ b/dir.c
@@ -13,6 +13,7 @@
 #include "dir.h"
 #include "environment.h"
 #include "gettext.h"
+#include "name-hash.h"
 #include "object-file.h"
 #include "object-store.h"
 #include "attr.h"
diff --git a/entry.c b/entry.c
index 91a540bd29..7791cc999c 100644
--- a/entry.c
+++ b/entry.c
@@ -5,6 +5,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "hex.h"
+#include "name-hash.h"
 #include "streaming.h"
 #include "submodule.h"
 #include "symlinks.h"
diff --git a/merge-recursive.c b/merge-recursive.c
index 8e87b6386d..b341ba4f38 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -23,6 +23,7 @@
 #include "ll-merge.h"
 #include "lockfile.h"
 #include "match-trees.h"
+#include "name-hash.h"
 #include "object-file.h"
 #include "object-name.h"
 #include "object-store.h"
diff --git a/name-hash.c b/name-hash.c
index fb13716e43..52ce47ea39 100644
--- a/name-hash.c
+++ b/name-hash.c
@@ -8,6 +8,7 @@
 #include "cache.h"
 #include "environment.h"
 #include "gettext.h"
+#include "name-hash.h"
 #include "thread-utils.h"
 #include "trace.h"
 #include "trace2.h"
diff --git a/name-hash.h b/name-hash.h
new file mode 100644
index 0000000000..b1b4b0fb33
--- /dev/null
+++ b/name-hash.h
@@ -0,0 +1,16 @@
+#ifndef NAME_HASH_H
+#define NAME_HASH_H
+
+struct cache_entry;
+struct index_state;
+
+int index_dir_exists(struct index_state *istate, const char *name, int namelen);
+void adjust_dirname_case(struct index_state *istate, char *name);
+struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int igncase);
+
+int test_lazy_init_name_hash(struct index_state *istate, int try_threaded);
+void add_name_hash(struct index_state *istate, struct cache_entry *ce);
+void remove_name_hash(struct index_state *istate, struct cache_entry *ce);
+void free_name_hash(struct index_state *istate);
+
+#endif /* NAME_HASH_H */
diff --git a/read-cache.c b/read-cache.c
index b99dbfd16b..e1016ae031 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -25,6 +25,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "mem-pool.h"
+#include "name-hash.h"
 #include "object-name.h"
 #include "resolve-undo.h"
 #include "revision.h"
diff --git a/sparse-index.c b/sparse-index.c
index 886054729e..60451daae8 100644
--- a/sparse-index.c
+++ b/sparse-index.c
@@ -2,6 +2,7 @@
 #include "alloc.h"
 #include "environment.h"
 #include "gettext.h"
+#include "name-hash.h"
 #include "repository.h"
 #include "sparse-index.h"
 #include "tree.h"
diff --git a/t/helper/test-lazy-init-name-hash.c b/t/helper/test-lazy-init-name-hash.c
index b83a75d19f..6944b7e825 100644
--- a/t/helper/test-lazy-init-name-hash.c
+++ b/t/helper/test-lazy-init-name-hash.c
@@ -2,6 +2,7 @@
 #include "test-tool.h"
 #include "cache.h"
 #include "environment.h"
+#include "name-hash.h"
 #include "parse-options.h"
 #include "repository.h"
 #include "setup.h"
diff --git a/unpack-trees.c b/unpack-trees.c
index e8c32a40dc..078c53f7a1 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -7,6 +7,7 @@
 #include "environment.h"
 #include "gettext.h"
 #include "hex.h"
+#include "name-hash.h"
 #include "tree.h"
 #include "tree-walk.h"
 #include "cache-tree.h"