-// SPDX-License-Identifier: GPL-2.0
-/*
- * This contains encryption functions for per-file encryption.
- *
- * 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 llcrypt_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.
- */
-/*
- * Linux commit 219d54332a09
- * tags/v5.4
- */
-
-#include <linux/pagemap.h>
-#include <linux/module.h>
-#include <linux/bio.h>
-#include <linux/namei.h>
-#include <lustre_compat.h>
-#include "llcrypt_private.h"
-
-static void __llcrypt_decrypt_bio(struct bio *bio, bool done)
-{
- struct bio_vec *bv;
-#ifdef HAVE_BVEC_ITER_ALL
- struct bvec_iter_all iter_all;
-#else
- int iter_all;
-#endif
-
- bio_for_each_segment_all(bv, bio, iter_all) {
- struct page *page = bv->bv_page;
- int ret = llcrypt_decrypt_pagecache_blocks(page, bv->bv_len,
- bv->bv_offset);
- if (ret)
- SetPageError(page);
- else if (done)
- SetPageUptodate(page);
- if (done)
- unlock_page(page);
- }
-}
-
-void llcrypt_decrypt_bio(struct bio *bio)
-{
- __llcrypt_decrypt_bio(bio, false);
-}
-EXPORT_SYMBOL(llcrypt_decrypt_bio);
-
-static void completion_pages(struct work_struct *work)
-{
- struct llcrypt_ctx *ctx = container_of(work, struct llcrypt_ctx, work);
- struct bio *bio = ctx->bio;
-
- __llcrypt_decrypt_bio(bio, true);
- llcrypt_release_ctx(ctx);
- bio_put(bio);
-}
-
-void llcrypt_enqueue_decrypt_bio(struct llcrypt_ctx *ctx, struct bio *bio)
-{
- INIT_WORK(&ctx->work, completion_pages);
- ctx->bio = bio;
- llcrypt_enqueue_decrypt_work(&ctx->work);
-}
-EXPORT_SYMBOL(llcrypt_enqueue_decrypt_bio);
-
-int llcrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
- sector_t pblk, unsigned int len)
-{
- const unsigned int blockbits = inode->i_blkbits;
- const unsigned int blocksize = 1 << blockbits;
- struct page *ciphertext_page;
- struct bio *bio;
- int ret, err = 0;
-
- ciphertext_page = llcrypt_alloc_bounce_page(GFP_NOWAIT);
- if (!ciphertext_page)
- return -ENOMEM;
-
- while (len--) {
- err = llcrypt_crypt_block(inode, FS_ENCRYPT, lblk,
- ZERO_PAGE(0), ciphertext_page,
- blocksize, 0, GFP_NOFS);
- if (err)
- goto errout;
-
- bio = cfs_bio_alloc(inode->i_sb->s_bdev, 1, REQ_OP_WRITE,
- GFP_NOWAIT);
- if (!bio) {
- err = -ENOMEM;
- goto errout;
- }
- bio->bi_iter.bi_sector = pblk << (blockbits - 9);
- ret = bio_add_page(bio, ciphertext_page, blocksize, 0);
- if (WARN_ON(ret != blocksize)) {
- /* should never happen! */
- bio_put(bio);
- err = -EIO;
- goto errout;
- }
- err = submit_bio_wait(bio);
- if (err == 0 && bio->bi_status)
- err = -EIO;
- bio_put(bio);
- if (err)
- goto errout;
- lblk++;
- pblk++;
- }
- err = 0;
-errout:
- llcrypt_free_bounce_page(ciphertext_page);
- return err;
-}
-EXPORT_SYMBOL(llcrypt_zeroout_range);