On Wednesday, February 21, 2018 6:46:48 AM IST Eric Biggers wrote:
> 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);'.
>
You are right. I will fix that up in the next iteration of the patchset.
--
chandan
