fscrypt: add "fscrypt_" prefix to fname_encrypt()

fname_encrypt() is a global function, due to being used in both fname.c
and hooks.c.  So it should be prefixed with "fscrypt_", like all the
other global functions in fs/crypto/.

Link: https://lore.kernel.org/r/20200120071736.45915-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

fs/crypto/fname.c

@@ -28,15 +28,15 @@ static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
 }
 
 /**
- * fname_encrypt() - encrypt a filename
+ * fscrypt_fname_encrypt() - encrypt a filename
  *
  * The output buffer must be at least as large as the input buffer.
  * Any extra space is filled with NUL padding before encryption.
  *
  * Return: 0 on success, -errno on failure
  */
-int fname_encrypt(const struct inode *inode, const struct qstr *iname,
-		  u8 *out, unsigned int olen)
+int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
+			  u8 *out, unsigned int olen)
 {
 	struct skcipher_request *req = NULL;
 	DECLARE_CRYPTO_WAIT(wait);
@@ -343,8 +343,8 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
 		if (!fname->crypto_buf.name)
 			return -ENOMEM;
 
-		ret = fname_encrypt(dir, iname, fname->crypto_buf.name,
-				    fname->crypto_buf.len);
+		ret = fscrypt_fname_encrypt(dir, iname, fname->crypto_buf.name,
+					    fname->crypto_buf.len);
 		if (ret)
 			goto errout;
 		fname->disk_name.name = fname->crypto_buf.name;

fs/crypto/fscrypt_private.h

@@ -235,8 +235,9 @@ void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
 			 const struct fscrypt_info *ci);
 
 /* fname.c */
-extern int fname_encrypt(const struct inode *inode, const struct qstr *iname,
-			 u8 *out, unsigned int olen);
+extern int fscrypt_fname_encrypt(const struct inode *inode,
+				 const struct qstr *iname,
+				 u8 *out, unsigned int olen);
 extern bool fscrypt_fname_encrypted_size(const struct inode *inode,
 					 u32 orig_len, u32 max_len,
 					 u32 *encrypted_len_ret);

fs/crypto/hooks.c

@@ -187,7 +187,8 @@ int __fscrypt_encrypt_symlink(struct inode *inode, const char *target,
 	ciphertext_len = disk_link->len - sizeof(*sd);
 	sd->len = cpu_to_le16(ciphertext_len);
 
-	err = fname_encrypt(inode, &iname, sd->encrypted_path, ciphertext_len);
+	err = fscrypt_fname_encrypt(inode, &iname, sd->encrypted_path,
+				    ciphertext_len);
 	if (err)
 		goto err_free_sd;