From: Mike Snitzer Date: Thu, 9 Apr 2015 20:53:24 +0000 (-0400) Subject: dm crypt: leverage immutable biovecs when decrypting on read X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5977907937afa2b5584a874d44ba6c0f56aeaa9c;p=linux-beck.git dm crypt: leverage immutable biovecs when decrypting on read Commit 003b5c571 ("block: Convert drivers to immutable biovecs") stopped short of changing dm-crypt to leverage the fact that the biovec array of a bio will no longer be modified. Switch to using bio_clone_fast() when cloning bios for decryption after read. Signed-off-by: Mike Snitzer --- diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index ea09d5464a9f..aa1238facbeb 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1124,15 +1124,15 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone) static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) { struct crypt_config *cc = io->cc; - struct bio *base_bio = io->base_bio; struct bio *clone; /* - * The block layer might modify the bvec array, so always - * copy the required bvecs because we need the original - * one in order to decrypt the whole bio data *afterwards*. + * We need the original biovec array in order to decrypt + * the whole bio data *afterwards* -- thanks to immutable + * biovecs we don't need to worry about the block layer + * modifying the biovec array; so leverage bio_clone_fast(). */ - clone = bio_clone_bioset(base_bio, gfp, cc->bs); + clone = bio_clone_fast(io->base_bio, gfp, cc->bs); if (!clone) return 1;