fscrypt: clean up comments in bio.c

The file comment in bio.c is almost completely irrelevant to the actual
contents of the file; it was originally copied from crypto.c.  Fix it
up, and also add a kerneldoc comment for fscrypt_decrypt_bio().

Link: https://lore.kernel.org/r/20210909190737.140841-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
This commit is contained in:
Eric Biggers 2021-09-09 12:07:37 -07:00
parent 4373b3dc92
commit f262ca7db7

View File

@ -1,23 +1,10 @@
// SPDX-License-Identifier: GPL-2.0
/*
* This contains encryption functions for per-file encryption.
* Utility functions for file contents encryption/decryption on
* block device-based filesystems.
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility
*
* Written by Michael Halcrow, 2014.
*
* Filename encryption additions
* Uday Savagaonkar, 2014
* Encryption policy handling additions
* Ildar Muslukhov, 2014
* Add fscrypt_pullback_bio_page()
* Jaegeuk Kim, 2015.
*
* This has not yet undergone a rigorous security audit.
*
* The usage of AES-XTS should conform to recommendations in NIST
* Special Publication 800-38E and IEEE P1619/D16.
*/
#include <linux/pagemap.h>
@ -26,6 +13,21 @@
#include <linux/namei.h>
#include "fscrypt_private.h"
/**
* fscrypt_decrypt_bio() - decrypt the contents of a bio
* @bio: the bio to decrypt
*
* Decrypt the contents of a "read" bio following successful completion of the
* underlying disk read. The bio must be reading a whole number of blocks of an
* encrypted file directly into the page cache. If the bio is reading the
* ciphertext into bounce pages instead of the page cache (for example, because
* the file is also compressed, so decompression is required after decryption),
* then this function isn't applicable. This function may sleep, so it must be
* called from a workqueue rather than from the bio's bi_end_io callback.
*
* This function sets PG_error on any pages that contain any blocks that failed
* to be decrypted. The filesystem must not mark such pages uptodate.
*/
void fscrypt_decrypt_bio(struct bio *bio)
{
struct bio_vec *bv;