Merge commit 'v2.6.26-rc9' into sched/devel
[pandora-kernel.git] / drivers / md / dm-crypt.c
index c45bd0e..ab6a61d 100644 (file)
@@ -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
         */
@@ -123,7 +125,7 @@ struct crypt_config {
 
        char cipher[CRYPTO_MAX_ALG_NAME];
        char chainmode[CRYPTO_MAX_ALG_NAME];
-       struct crypto_blkcipher *tfm;
+       struct crypto_ablkcipher *tfm;
        unsigned long flags;
        unsigned int key_size;
        u8 key[0];
@@ -217,7 +219,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
                return PTR_ERR(essiv_tfm);
        }
        if (crypto_cipher_blocksize(essiv_tfm) !=
-           crypto_blkcipher_ivsize(cc->tfm)) {
+           crypto_ablkcipher_ivsize(cc->tfm)) {
                ti->error = "Block size of ESSIV cipher does "
                            "not match IV size of block cipher";
                crypto_free_cipher(essiv_tfm);
@@ -254,7 +256,7 @@ static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
                              const char *opts)
 {
-       unsigned int bs = crypto_blkcipher_blocksize(cc->tfm);
+       unsigned bs = crypto_ablkcipher_blocksize(cc->tfm);
        int log = ilog2(bs);
 
        /* we need to calculate how far we must shift the sector count
@@ -318,38 +320,6 @@ static struct crypt_iv_operations crypt_iv_null_ops = {
        .generator = crypt_iv_null_gen
 };
 
-static int
-crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out,
-                          struct scatterlist *in, unsigned int length,
-                          int write, sector_t sector)
-{
-       u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64))));
-       struct blkcipher_desc desc = {
-               .tfm = cc->tfm,
-               .info = iv,
-               .flags = CRYPTO_TFM_REQ_MAY_SLEEP,
-       };
-       int r;
-
-       if (cc->iv_gen_ops) {
-               r = cc->iv_gen_ops->generator(cc, iv, sector);
-               if (r < 0)
-                       return r;
-
-               if (write)
-                       r = crypto_blkcipher_encrypt_iv(&desc, out, in, length);
-               else
-                       r = crypto_blkcipher_decrypt_iv(&desc, out, in, length);
-       } else {
-               if (write)
-                       r = crypto_blkcipher_encrypt(&desc, out, in, length);
-               else
-                       r = crypto_blkcipher_decrypt(&desc, out, in, length);
-       }
-
-       return r;
-}
-
 static void crypt_convert_init(struct crypt_config *cc,
                               struct convert_context *ctx,
                               struct bio *bio_out, struct bio *bio_in,
@@ -363,29 +333,29 @@ 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,
-                              struct convert_context *ctx)
+                              struct convert_context *ctx,
+                              struct ablkcipher_request *req)
 {
        struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in);
        struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out);
-       struct dm_crypt_request dmreq;
+       struct dm_crypt_request *dmreq;
+       u8 *iv;
+       int r = 0;
+
+       dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
+       iv = (u8 *)ALIGN((unsigned long)(dmreq + 1),
+                        crypto_ablkcipher_alignmask(cc->tfm) + 1);
 
-       sg_init_table(&dmreq.sg_in, 1);
-       sg_set_page(&dmreq.sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
+       sg_init_table(&dmreq->sg_in, 1);
+       sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
                    bv_in->bv_offset + ctx->offset_in);
 
-       sg_init_table(&dmreq.sg_out, 1);
-       sg_set_page(&dmreq.sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT,
+       sg_init_table(&dmreq->sg_out, 1);
+       sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT,
                    bv_out->bv_offset + ctx->offset_out);
 
        ctx->offset_in += 1 << SECTOR_SHIFT;
@@ -400,10 +370,21 @@ static int crypt_convert_block(struct crypt_config *cc,
                ctx->idx_out++;
        }
 
-       return crypt_convert_scatterlist(cc, &dmreq.sg_out, &dmreq.sg_in,
-                                        dmreq.sg_in.length,
-                                        bio_data_dir(ctx->bio_in) == WRITE,
-                                        ctx->sector);
+       if (cc->iv_gen_ops) {
+               r = cc->iv_gen_ops->generator(cc, iv, ctx->sector);
+               if (r < 0)
+                       return r;
+       }
+
+       ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
+                                    1 << SECTOR_SHIFT, iv);
+
+       if (bio_data_dir(ctx->bio_in) == WRITE)
+               r = crypto_ablkcipher_encrypt(req);
+       else
+               r = crypto_ablkcipher_decrypt(req);
+
+       return r;
 }
 
 static void kcryptd_async_done(struct crypto_async_request *async_req,
@@ -425,27 +406,43 @@ 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) {
-               r = crypt_convert_block(cc, ctx);
-               if (r < 0)
-                       break;
 
-               ctx->sector++;
+               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:
+                       cc->req = NULL;
+                       ctx->sector++;
+                       continue;
+
+               /* sync */
+               case 0:
+                       atomic_dec(&ctx->pending);
+                       ctx->sector++;
+                       cond_resched();
+                       continue;
+
+               /* 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)
@@ -622,8 +619,10 @@ 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)
@@ -696,13 +695,21 @@ 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, 0);
-               if (unlikely(r < 0))
-                       return;
+               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;
+               } else
+                       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);
+               }
        }
 }
 
@@ -734,12 +741,17 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
        struct crypt_config *cc = io->target->private;
        int r = 0;
 
+       atomic_inc(&io->pending);
+
        crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
                           io->sector);
 
        r = crypt_convert(cc, &io->ctx);
 
-       kcryptd_crypt_read_done(io, r);
+       if (atomic_dec_and_test(&io->ctx.pending))
+               kcryptd_crypt_read_done(io, r);
+
+       crypt_dec_pending(io);
 }
 
 static void kcryptd_async_done(struct crypto_async_request *async_req,
@@ -856,7 +868,7 @@ static int crypt_wipe_key(struct crypt_config *cc)
 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 {
        struct crypt_config *cc;
-       struct crypto_blkcipher *tfm;
+       struct crypto_ablkcipher *tfm;
        char *tmp;
        char *cipher;
        char *chainmode;
@@ -910,7 +922,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                goto bad_cipher;
        }
 
-       tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
+       tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0);
        if (IS_ERR(tfm)) {
                ti->error = "Error allocating crypto tfm";
                goto bad_cipher;
@@ -944,7 +956,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
            cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0)
                goto bad_ivmode;
 
-       cc->iv_size = crypto_blkcipher_ivsize(tfm);
+       cc->iv_size = crypto_ablkcipher_ivsize(tfm);
        if (cc->iv_size)
                /* at least a 64 bit sector number should fit in our buffer */
                cc->iv_size = max(cc->iv_size,
@@ -965,7 +977,10 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
        }
 
        cc->dmreq_start = sizeof(struct ablkcipher_request);
+       cc->dmreq_start += crypto_ablkcipher_reqsize(tfm);
        cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
+       cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) &
+                          ~(crypto_tfm_ctx_alignment() - 1);
 
        cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
                        sizeof(struct dm_crypt_request) + cc->iv_size);
@@ -987,7 +1002,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                goto bad_bs;
        }
 
-       if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) {
+       if (crypto_ablkcipher_setkey(tfm, cc->key, key_size) < 0) {
                ti->error = "Error setting key";
                goto bad_device;
        }
@@ -1034,6 +1049,7 @@ 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;
 
@@ -1055,7 +1071,7 @@ bad_slab_pool:
        if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
                cc->iv_gen_ops->dtr(cc);
 bad_ivmode:
-       crypto_free_blkcipher(tfm);
+       crypto_free_ablkcipher(tfm);
 bad_cipher:
        /* Must zero key material before freeing */
        memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8));
@@ -1081,7 +1097,7 @@ static void crypt_dtr(struct dm_target *ti)
        kfree(cc->iv_mode);
        if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
                cc->iv_gen_ops->dtr(cc);
-       crypto_free_blkcipher(cc->tfm);
+       crypto_free_ablkcipher(cc->tfm);
        dm_put_device(ti, cc->dev);
 
        /* Must zero key material before freeing */