From e11a4eba4faaa91076699fade557a5f2f38b05b3 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Fri, 24 Jul 2020 18:44:56 +0000 Subject: [PATCH] FROMLIST: direct-io: add support for fscrypt using blk-crypto Set bio crypt contexts on bios by calling into fscrypt when required, and explicitly check for DUN continuity when adding pages to the bio. (While DUN continuity is usually implied by logical block contiguity, this is not the case when using certain fscrypt IV generation methods like IV_INO_LBLK_32). Signed-off-by: Eric Biggers Co-developed-by: Satya Tangirala Signed-off-by: Satya Tangirala Reviewed-by: Jaegeuk Kim Bug: 162255927 Link: https://lore.kernel.org/r/20200724184501.1651378-3-satyat@google.com Change-Id: I57ff74185004371c01ec35d806b0749583375c58 Signed-off-by: Eric Biggers --- fs/direct-io.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/direct-io.c b/fs/direct-io.c index d53fa92a1ab6..f6672c4030e3 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -392,6 +393,7 @@ dio_bio_alloc(struct dio *dio, struct dio_submit *sdio, sector_t first_sector, int nr_vecs) { struct bio *bio; + struct inode *inode = dio->inode; /* * bio_alloc() is guaranteed to return a bio when allowed to sleep and @@ -399,6 +401,9 @@ dio_bio_alloc(struct dio *dio, struct dio_submit *sdio, */ bio = bio_alloc(GFP_KERNEL, nr_vecs); + fscrypt_set_bio_crypt_ctx(bio, inode, + sdio->cur_page_fs_offset >> inode->i_blkbits, + GFP_KERNEL); bio_set_dev(bio, bdev); bio->bi_iter.bi_sector = first_sector; bio_set_op_attrs(bio, dio->op, dio->op_flags); @@ -763,9 +768,17 @@ static inline int dio_send_cur_page(struct dio *dio, struct dio_submit *sdio, * current logical offset in the file does not equal what would * be the next logical offset in the bio, submit the bio we * have. + * + * When fscrypt inline encryption is used, data unit number + * (DUN) contiguity is also required. Normally that's implied + * by logical contiguity. However, certain IV generation + * methods (e.g. IV_INO_LBLK_32) don't guarantee it. So, we + * must explicitly check fscrypt_mergeable_bio() too. */ if (sdio->final_block_in_bio != sdio->cur_page_block || - cur_offset != bio_next_offset) + cur_offset != bio_next_offset || + !fscrypt_mergeable_bio(sdio->bio, dio->inode, + cur_offset >> dio->inode->i_blkbits)) dio_bio_submit(dio, sdio); }