mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
4e4cbee93d
Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
146 lines
3.3 KiB
C
146 lines
3.3 KiB
C
/*
|
|
* 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 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>
|
|
#include <linux/module.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/namei.h>
|
|
#include "fscrypt_private.h"
|
|
|
|
/*
|
|
* Call fscrypt_decrypt_page on every single page, reusing the encryption
|
|
* context.
|
|
*/
|
|
static void completion_pages(struct work_struct *work)
|
|
{
|
|
struct fscrypt_ctx *ctx =
|
|
container_of(work, struct fscrypt_ctx, r.work);
|
|
struct bio *bio = ctx->r.bio;
|
|
struct bio_vec *bv;
|
|
int i;
|
|
|
|
bio_for_each_segment_all(bv, bio, i) {
|
|
struct page *page = bv->bv_page;
|
|
int ret = fscrypt_decrypt_page(page->mapping->host, page,
|
|
PAGE_SIZE, 0, page->index);
|
|
|
|
if (ret) {
|
|
WARN_ON_ONCE(1);
|
|
SetPageError(page);
|
|
} else {
|
|
SetPageUptodate(page);
|
|
}
|
|
unlock_page(page);
|
|
}
|
|
fscrypt_release_ctx(ctx);
|
|
bio_put(bio);
|
|
}
|
|
|
|
void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
|
|
{
|
|
INIT_WORK(&ctx->r.work, completion_pages);
|
|
ctx->r.bio = bio;
|
|
queue_work(fscrypt_read_workqueue, &ctx->r.work);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
|
|
|
|
void fscrypt_pullback_bio_page(struct page **page, bool restore)
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
struct page *bounce_page;
|
|
|
|
/* The bounce data pages are unmapped. */
|
|
if ((*page)->mapping)
|
|
return;
|
|
|
|
/* The bounce data page is unmapped. */
|
|
bounce_page = *page;
|
|
ctx = (struct fscrypt_ctx *)page_private(bounce_page);
|
|
|
|
/* restore control page */
|
|
*page = ctx->w.control_page;
|
|
|
|
if (restore)
|
|
fscrypt_restore_control_page(bounce_page);
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_pullback_bio_page);
|
|
|
|
int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
|
|
sector_t pblk, unsigned int len)
|
|
{
|
|
struct fscrypt_ctx *ctx;
|
|
struct page *ciphertext_page = NULL;
|
|
struct bio *bio;
|
|
int ret, err = 0;
|
|
|
|
BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
|
|
|
|
ctx = fscrypt_get_ctx(inode, GFP_NOFS);
|
|
if (IS_ERR(ctx))
|
|
return PTR_ERR(ctx);
|
|
|
|
ciphertext_page = fscrypt_alloc_bounce_page(ctx, GFP_NOWAIT);
|
|
if (IS_ERR(ciphertext_page)) {
|
|
err = PTR_ERR(ciphertext_page);
|
|
goto errout;
|
|
}
|
|
|
|
while (len--) {
|
|
err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk,
|
|
ZERO_PAGE(0), ciphertext_page,
|
|
PAGE_SIZE, 0, GFP_NOFS);
|
|
if (err)
|
|
goto errout;
|
|
|
|
bio = bio_alloc(GFP_NOWAIT, 1);
|
|
if (!bio) {
|
|
err = -ENOMEM;
|
|
goto errout;
|
|
}
|
|
bio->bi_bdev = inode->i_sb->s_bdev;
|
|
bio->bi_iter.bi_sector =
|
|
pblk << (inode->i_sb->s_blocksize_bits - 9);
|
|
bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
|
|
ret = bio_add_page(bio, ciphertext_page,
|
|
inode->i_sb->s_blocksize, 0);
|
|
if (ret != inode->i_sb->s_blocksize) {
|
|
/* should never happen! */
|
|
WARN_ON(1);
|
|
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:
|
|
fscrypt_release_ctx(ctx);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(fscrypt_zeroout_range);
|