From patchwork Mon Nov 29 22:53:07 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Milan Broz X-Patchwork-Id: 365562 X-Patchwork-Delegate: agk@redhat.com Received: from mx3-phx2.redhat.com (mx3-phx2.redhat.com [209.132.183.24]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id oATMuPJM013209 for ; Mon, 29 Nov 2010 22:56:45 GMT Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by mx3-phx2.redhat.com (8.13.8/8.13.8) with ESMTP id oATMrt5x022952; Mon, 29 Nov 2010 17:53:56 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id oATMrcKf004411 for ; Mon, 29 Nov 2010 17:53:38 -0500 Received: from tawny.mazyland.cz (vpn1-7-138.ams2.redhat.com [10.36.7.138]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id oATMrEnY017289; Mon, 29 Nov 2010 17:53:32 -0500 From: Milan Broz To: dm-devel@redhat.com Date: Mon, 29 Nov 2010 23:53:07 +0100 Message-Id: <1291071187-6231-3-git-send-email-mbroz@redhat.com> In-Reply-To: <1291071187-6231-1-git-send-email-mbroz@redhat.com> References: <1291071187-6231-1-git-send-email-mbroz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-loop: dm-devel@redhat.com Cc: Milan Broz Subject: [dm-devel] [PATCH] dm crypt: use IO thread for reads only if mempool is exhausted X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk Reply-To: device-mapper development List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Mon, 29 Nov 2010 22:56:45 +0000 (UTC) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index b4dac68..98a7ad0 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -785,26 +785,30 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone) clone->bi_destructor = dm_crypt_bio_destructor; } -static void kcryptd_io_read(struct dm_crypt_io *io) +static void kcryptd_unplug(struct crypt_config *cc) +{ + blk_unplug(bdev_get_queue(cc->dev->bdev)); +} + +static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) { struct crypt_config *cc = io->target->private; struct bio *base_bio = io->base_bio; struct bio *clone; - crypt_inc_pending(io); - /* * 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*. */ - clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); - if (unlikely(!clone)) { - io->error = -ENOMEM; - crypt_dec_pending(io); - return; + clone = bio_alloc_bioset(gfp, bio_segments(base_bio), cc->bs); + if (!clone) { + kcryptd_unplug(cc); + return 1; } + crypt_inc_pending(io); + clone_init(io, clone); clone->bi_idx = 0; clone->bi_vcnt = bio_segments(base_bio); @@ -814,6 +818,7 @@ static void kcryptd_io_read(struct dm_crypt_io *io) sizeof(struct bio_vec) * clone->bi_vcnt); generic_make_request(clone); + return 0; } static void kcryptd_io_write(struct dm_crypt_io *io) @@ -826,9 +831,12 @@ static void kcryptd_io(struct work_struct *work) { struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); - if (bio_data_dir(io->base_bio) == READ) - kcryptd_io_read(io); - else + if (bio_data_dir(io->base_bio) == READ) { + crypt_inc_pending(io); + if (kcryptd_io_read(io, GFP_NOIO)) + io->error = -ENOMEM; + crypt_dec_pending(io); + } else kcryptd_io_write(io); } @@ -1446,9 +1454,10 @@ static int crypt_map(struct dm_target *ti, struct bio *bio, io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector)); - if (bio_data_dir(io->base_bio) == READ) - kcryptd_queue_io(io); - else + if (bio_data_dir(io->base_bio) == READ) { + if (kcryptd_io_read(io, GFP_NOWAIT)) + kcryptd_queue_io(io); + } else kcryptd_queue_crypt(io); return DM_MAPIO_SUBMITTED;