On Mon, Feb 12, 2018 at 03:13:43PM +0530, Chandan Rajendra wrote:
> For block size < page size, This commit adds code to encrypt all zeroed
> out blocks of a page.
>
> Signed-off-by: Chandan Rajendra <chandan@xxxxxxxxxxxxxxxxxx>
> ---
> fs/crypto/bio.c | 38 +++++++++++++++++++++++++-------------
> 1 file changed, 25 insertions(+), 13 deletions(-)
>
> diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
> index 378df08..4d0d14f 100644
> --- a/fs/crypto/bio.c
> +++ b/fs/crypto/bio.c
> @@ -104,10 +104,12 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
> {
> struct fscrypt_ctx *ctx;
> struct page *ciphertext_page = NULL;
> + unsigned int page_nr_blks;
> + unsigned int offset;
> + unsigned int page_io_len;
> struct bio *bio;
> int ret, err = 0;
> -
> - BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
> + int i;
>
> ctx = fscrypt_get_ctx(inode, GFP_NOFS);
> if (IS_ERR(ctx))
> @@ -119,12 +121,23 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
> goto errout;
> }
>
> - while (len--) {
> - err = fscrypt_do_block_crypto(inode, FS_ENCRYPT, lblk,
> - ZERO_PAGE(0), ciphertext_page,
> - PAGE_SIZE, 0, GFP_NOFS);
> - if (err)
> - goto errout;
> + page_nr_blks = 1 << (PAGE_SHIFT - inode->i_blkbits);
> +
> + while (len) {
> + page_nr_blks = min_t(unsigned int, page_nr_blks, len);
> + page_io_len = page_nr_blks << inode->i_blkbits;
> + offset = 0;
The 'page_io_len' variable isn't needed, since 'offset == page_io_len' after the
encryption loop. You can do 'bio_add_page(bio, ciphertext_page, offset, 0);'.
Eric
