dm crypt: prepare async callback fn

dm-crypt: Use crypto ablkcipher interface

Prepare callback function for async crypto operation.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 41 insertions, 4 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 2ea3eb99c91f..c45bd0e59dcc 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -406,11 +406,17 @@ static int crypt_convert_block(struct crypt_config *cc,
                                          ctx->sector);
 }
 
+static void kcryptd_async_done(struct crypto_async_request *async_req,
+                               int error);
 static void crypt_alloc_req(struct crypt_config *cc,
                             struct convert_context *ctx)
 {
         if (!cc->req)
                 cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
+        ablkcipher_request_set_tfm(cc->req, cc->tfm);
+        ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+                                             CRYPTO_TFM_REQ_MAY_SLEEP,
+                                             kcryptd_async_done, ctx);
 }
 
 /*
@@ -615,6 +621,9 @@ 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;
+
+        generic_make_request(clone);
 }
 
 static void kcryptd_io(struct work_struct *work)
@@ -635,7 +644,8 @@ static void kcryptd_queue_io(struct dm_crypt_io *io)
         queue_work(cc->io_queue, &io->work);
 }
 
-static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error)
+static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
+                                          int error, int async)
 {
         struct bio *clone = io->ctx.bio_out;
         struct crypt_config *cc = io->target->private;
@@ -653,8 +663,12 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error)
         clone->bi_sector = cc->start + io->sector;
         io->sector += bio_sectors(clone);
 
-        atomic_inc(&io->pending);
-        generic_make_request(clone);
+        if (async)
+                kcryptd_queue_io(io);
+        else {
+                atomic_inc(&io->pending);
+                generic_make_request(clone);
+        }
 }
 
 static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
@@ -682,7 +696,7 @@ static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
 
                 r = crypt_convert(cc, &io->ctx);
 
-                kcryptd_crypt_write_io_submit(io, r);
+                kcryptd_crypt_write_io_submit(io, r, 0);
                 if (unlikely(r < 0))
                         return;
 
@@ -728,6 +742,29 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
         kcryptd_crypt_read_done(io, r);
 }
 
+static void kcryptd_async_done(struct crypto_async_request *async_req,
+                               int error)
+{
+        struct convert_context *ctx = async_req->data;
+        struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
+        struct crypt_config *cc = io->target->private;
+
+        if (error == -EINPROGRESS) {
+                complete(&ctx->restart);
+                return;
+        }
+
+        mempool_free(ablkcipher_request_cast(async_req), cc->req_pool);
+
+        if (!atomic_dec_and_test(&ctx->pending))
+                return;
+
+        if (bio_data_dir(io->base_bio) == READ)
+                kcryptd_crypt_read_done(io, error);
+        else
+                kcryptd_crypt_write_io_submit(io, error, 1);
+}
+
 static void kcryptd_crypt(struct work_struct *work)
 {
         struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);