fscrypt: move fscrypt_is_dot_dotdot() to fs/crypto/fname.c

Only fs/crypto/fname.c cares about treating the "." and ".." filenames
specially with regards to encryption, so move fscrypt_is_dot_dotdot()
from fscrypt.h to there.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/crypto/fname.c

@@ -15,6 +15,17 @@
 #include <linux/ratelimit.h>
 #include "fscrypt_private.h"
 
+static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
+{
+	if (str->len == 1 && str->name[0] == '.')
+		return true;
+
+	if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
+		return true;
+
+	return false;
+}
+
 /**
  * fname_encrypt() - encrypt a filename
  *

include/linux/fscrypt.h

@@ -57,17 +57,6 @@ struct fscrypt_name {
 /* Maximum value for the third parameter of fscrypt_operations.set_context(). */
 #define FSCRYPT_SET_CONTEXT_MAX_SIZE	28
 
-static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
-{
-	if (str->len == 1 && str->name[0] == '.')
-		return true;
-
-	if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
-		return true;
-
-	return false;
-}
-
 #if __FS_HAS_ENCRYPTION
 #include <linux/fscrypt_supp.h>
 #else