fscrypt: remove fscrypt_fname_usr_to_disk()

fscrypt_fname_usr_to_disk() sounded very generic but was actually only
used to encrypt symlinks.  Remove it now that all filesystems have been
switched over to fscrypt_encrypt_symlink().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/crypto/fname.c

@@ -311,35 +311,6 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
 }
 EXPORT_SYMBOL(fscrypt_fname_disk_to_usr);
 
-/**
- * fscrypt_fname_usr_to_disk() - converts a filename from user space to disk
- * space
- *
- * The caller must have allocated sufficient memory for the @oname string.
- *
- * Return: 0 on success, -errno on failure
- */
-int fscrypt_fname_usr_to_disk(struct inode *inode,
-			const struct qstr *iname,
-			struct fscrypt_str *oname)
-{
-	if (fscrypt_is_dot_dotdot(iname)) {
-		oname->name[0] = '.';
-		oname->name[iname->len - 1] = '.';
-		oname->len = iname->len;
-		return 0;
-	}
-	if (inode->i_crypt_info)
-		return fname_encrypt(inode, iname, oname);
-	/*
-	 * Without a proper key, a user is not allowed to modify the filenames
-	 * in a directory. Consequently, a user space name cannot be mapped to
-	 * a disk-space name
-	 */
-	return -ENOKEY;
-}
-EXPORT_SYMBOL(fscrypt_fname_usr_to_disk);
-
 /**
  * fscrypt_setup_filename() - prepare to search a possibly encrypted directory
  * @dir: the directory that will be searched

include/linux/fscrypt_notsupp.h

@@ -159,13 +159,6 @@ static inline int fscrypt_fname_disk_to_usr(struct inode *inode,
 	return -EOPNOTSUPP;
 }
 
-static inline int fscrypt_fname_usr_to_disk(struct inode *inode,
-					    const struct qstr *iname,
-					    struct fscrypt_str *oname)
-{
-	return -EOPNOTSUPP;
-}
-
 static inline bool fscrypt_match_name(const struct fscrypt_name *fname,
 				      const u8 *de_name, u32 de_name_len)
 {

include/linux/fscrypt_supp.h

@@ -113,8 +113,6 @@ extern int fscrypt_fname_alloc_buffer(const struct inode *, u32,
 extern void fscrypt_fname_free_buffer(struct fscrypt_str *);
 extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32,
 			const struct fscrypt_str *, struct fscrypt_str *);
-extern int fscrypt_fname_usr_to_disk(struct inode *, const struct qstr *,
-			struct fscrypt_str *);
 
 #define FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE	32