diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/md/dm-crypt.c | 58 |
1 files changed, 30 insertions, 28 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index b04f98d..835def1 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1,7 +1,7 @@ /* * Copyright (C) 2003 Christophe Saout <christophe@saout.de> * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> - * Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved. + * Copyright (C) 2006-2008 Red Hat, Inc. All rights reserved. * * This file is released under the GPL. */ @@ -93,6 +93,8 @@ struct crypt_config { struct workqueue_struct *io_queue; struct workqueue_struct *crypt_queue; + wait_queue_head_t writeq; + /* * crypto related data */ @@ -331,14 +333,7 @@ static void crypt_convert_init(struct crypt_config *cc, ctx->idx_out = bio_out ? bio_out->bi_idx : 0; ctx->sector = sector + cc->iv_offset; init_completion(&ctx->restart); - /* - * Crypto operation can be asynchronous, - * ctx->pending is increased after request submission. - * We need to ensure that we don't call the crypt finish - * operation before pending got incremented - * (dependent on crypt submission return code). - */ - atomic_set(&ctx->pending, 2); + atomic_set(&ctx->pending, 1); } static int crypt_convert_block(struct crypt_config *cc, @@ -411,43 +406,42 @@ static void crypt_alloc_req(struct crypt_config *cc, static int crypt_convert(struct crypt_config *cc, struct convert_context *ctx) { - int r = 0; + int r; while(ctx->idx_in < ctx->bio_in->bi_vcnt && ctx->idx_out < ctx->bio_out->bi_vcnt) { crypt_alloc_req(cc, ctx); + atomic_inc(&ctx->pending); + r = crypt_convert_block(cc, ctx, cc->req); switch (r) { + /* async */ case -EBUSY: wait_for_completion(&ctx->restart); INIT_COMPLETION(ctx->restart); /* fall through*/ case -EINPROGRESS: - atomic_inc(&ctx->pending); cc->req = NULL; - r = 0; - /* fall through*/ + ctx->sector++; + continue; + + /* sync */ case 0: + atomic_dec(&ctx->pending); ctx->sector++; continue; - } - break; + /* error */ + default: + atomic_dec(&ctx->pending); + return r; + } } - /* - * If there are pending crypto operation run async - * code. Otherwise process return code synchronously. - * The step of 2 ensures that async finish doesn't - * call crypto finish too early. - */ - if (atomic_sub_return(2, &ctx->pending)) - return -EINPROGRESS; - - return r; + return 0; } static void dm_crypt_bio_destructor(struct bio *bio) @@ -624,8 +618,10 @@ static void kcryptd_io_read(struct dm_crypt_io *io) static void kcryptd_io_write(struct dm_crypt_io *io) { struct bio *clone = io->ctx.bio_out; + struct crypt_config *cc = io->target->private; generic_make_request(clone); + wake_up(&cc->writeq); } static void kcryptd_io(struct work_struct *work) @@ -698,7 +694,8 @@ static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) r = crypt_convert(cc, &io->ctx); - if (r != -EINPROGRESS) { + if (atomic_dec_and_test(&io->ctx.pending)) { + /* processed, no running async crypto */ kcryptd_crypt_write_io_submit(io, r, 0); if (unlikely(r < 0)) return; @@ -706,8 +703,12 @@ static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) atomic_inc(&io->pending); /* out of memory -> run queues */ - if (unlikely(remaining)) + if (unlikely(remaining)) { + /* wait for async crypto then reinitialize pending */ + wait_event(cc->writeq, !atomic_read(&io->ctx.pending)); + atomic_set(&io->ctx.pending, 1); congestion_wait(WRITE, HZ/100); + } } } @@ -746,7 +747,7 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) r = crypt_convert(cc, &io->ctx); - if (r != -EINPROGRESS) + if (atomic_dec_and_test(&io->ctx.pending)) kcryptd_crypt_read_done(io, r); crypt_dec_pending(io); @@ -1047,6 +1048,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) goto bad_crypt_queue; } + init_waitqueue_head(&cc->writeq); ti->private = cc; return 0; |