/*
   * Software async crypto daemon.
   *
   * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   *

   * Added AEAD support to cryptd.
   *    Authors: Tadeusz Struk (tadeusz.struk@intel.com)
   *             Adrian Hoban <adrian.hoban@intel.com>
   *             Gabriele Paoloni <gabriele.paoloni@intel.com>
   *             Aidan O'Mahony (aidan.o.mahony@intel.com)
   *    Copyright (c) 2010, Intel Corporation.
   *

   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License as published by the Free
   * Software Foundation; either version 2 of the License, or (at your option)
   * any later version.
   *
   */

  #include <crypto/internal/hash.h>

  #include <crypto/internal/aead.h>

  #include <crypto/internal/skcipher.h>

  #include <crypto/cryptd.h>

  #include <crypto/crypto_wq.h>

  #include <linux/atomic.h>

  #include <linux/err.h>
  #include <linux/init.h>
  #include <linux/kernel.h>

  #include <linux/list.h>
  #include <linux/module.h>

  #include <linux/scatterlist.h>
  #include <linux/sched.h>
  #include <linux/slab.h>

  #define CRYPTD_MAX_CPU_QLEN 1000

  struct cryptd_cpu_queue {

  	struct crypto_queue queue;

  	struct work_struct work;
  };
  
  struct cryptd_queue {

  	struct cryptd_cpu_queue __percpu *cpu_queue;

  };
  
  struct cryptd_instance_ctx {
  	struct crypto_spawn spawn;

  	struct cryptd_queue *queue;

  };

  struct skcipherd_instance_ctx {
  	struct crypto_skcipher_spawn spawn;
  	struct cryptd_queue *queue;
  };

  struct hashd_instance_ctx {
  	struct crypto_shash_spawn spawn;
  	struct cryptd_queue *queue;
  };

  struct aead_instance_ctx {
  	struct crypto_aead_spawn aead_spawn;
  	struct cryptd_queue *queue;
  };

  struct cryptd_blkcipher_ctx {

  	atomic_t refcnt;

  	struct crypto_blkcipher *child;
  };
  
  struct cryptd_blkcipher_request_ctx {
  	crypto_completion_t complete;
  };

  struct cryptd_skcipher_ctx {
  	atomic_t refcnt;
  	struct crypto_skcipher *child;
  };
  
  struct cryptd_skcipher_request_ctx {
  	crypto_completion_t complete;
  };

  struct cryptd_hash_ctx {

  	atomic_t refcnt;

  	struct crypto_shash *child;

  };
  
  struct cryptd_hash_request_ctx {
  	crypto_completion_t complete;

  	struct shash_desc desc;

  };

  struct cryptd_aead_ctx {

  	atomic_t refcnt;

  	struct crypto_aead *child;
  };
  
  struct cryptd_aead_request_ctx {
  	crypto_completion_t complete;
  };

  static void cryptd_queue_worker(struct work_struct *work);
  
  static int cryptd_init_queue(struct cryptd_queue *queue,
  			     unsigned int max_cpu_qlen)
  {
  	int cpu;
  	struct cryptd_cpu_queue *cpu_queue;
  
  	queue->cpu_queue = alloc_percpu(struct cryptd_cpu_queue);
  	if (!queue->cpu_queue)
  		return -ENOMEM;
  	for_each_possible_cpu(cpu) {
  		cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
  		crypto_init_queue(&cpu_queue->queue, max_cpu_qlen);
  		INIT_WORK(&cpu_queue->work, cryptd_queue_worker);
  	}
  	return 0;
  }
  
  static void cryptd_fini_queue(struct cryptd_queue *queue)
  {
  	int cpu;
  	struct cryptd_cpu_queue *cpu_queue;
  
  	for_each_possible_cpu(cpu) {
  		cpu_queue = per_cpu_ptr(queue->cpu_queue, cpu);
  		BUG_ON(cpu_queue->queue.qlen);
  	}
  	free_percpu(queue->cpu_queue);
  }
  
  static int cryptd_enqueue_request(struct cryptd_queue *queue,
  				  struct crypto_async_request *request)
  {
  	int cpu, err;
  	struct cryptd_cpu_queue *cpu_queue;

  	atomic_t *refcnt;
  	bool may_backlog;

  
  	cpu = get_cpu();

  	cpu_queue = this_cpu_ptr(queue->cpu_queue);

  	err = crypto_enqueue_request(&cpu_queue->queue, request);

  
  	refcnt = crypto_tfm_ctx(request->tfm);
  	may_backlog = request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG;
  
  	if (err == -EBUSY && !may_backlog)
  		goto out_put_cpu;

  	queue_work_on(cpu, kcrypto_wq, &cpu_queue->work);

  
  	if (!atomic_read(refcnt))
  		goto out_put_cpu;

  	atomic_inc(refcnt);
  
  out_put_cpu:

  	put_cpu();
  
  	return err;
  }
  
  /* Called in workqueue context, do one real cryption work (via
   * req->complete) and reschedule itself if there are more work to
   * do. */
  static void cryptd_queue_worker(struct work_struct *work)
  {
  	struct cryptd_cpu_queue *cpu_queue;
  	struct crypto_async_request *req, *backlog;
  
  	cpu_queue = container_of(work, struct cryptd_cpu_queue, work);

  	/*
  	 * Only handle one request at a time to avoid hogging crypto workqueue.
  	 * preempt_disable/enable is used to prevent being preempted by
  	 * cryptd_enqueue_request(). local_bh_disable/enable is used to prevent
  	 * cryptd_enqueue_request() being accessed from software interrupts.
  	 */
  	local_bh_disable();

  	preempt_disable();
  	backlog = crypto_get_backlog(&cpu_queue->queue);
  	req = crypto_dequeue_request(&cpu_queue->queue);
  	preempt_enable();

  	local_bh_enable();

  
  	if (!req)
  		return;
  
  	if (backlog)
  		backlog->complete(backlog, -EINPROGRESS);
  	req->complete(req, 0);
  
  	if (cpu_queue->queue.qlen)
  		queue_work(kcrypto_wq, &cpu_queue->work);
  }
  
  static inline struct cryptd_queue *cryptd_get_queue(struct crypto_tfm *tfm)

  {
  	struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
  	struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);

  	return ictx->queue;

  }

  static inline void cryptd_check_internal(struct rtattr **tb, u32 *type,
  					 u32 *mask)
  {
  	struct crypto_attr_type *algt;
  
  	algt = crypto_get_attr_type(tb);
  	if (IS_ERR(algt))
  		return;

  	*type |= algt->type & CRYPTO_ALG_INTERNAL;
  	*mask |= algt->mask & CRYPTO_ALG_INTERNAL;

  }

  static int cryptd_blkcipher_setkey(struct crypto_ablkcipher *parent,
  				   const u8 *key, unsigned int keylen)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(parent);
  	struct crypto_blkcipher *child = ctx->child;
  	int err;
  
  	crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  	crypto_blkcipher_set_flags(child, crypto_ablkcipher_get_flags(parent) &
  					  CRYPTO_TFM_REQ_MASK);
  	err = crypto_blkcipher_setkey(child, key, keylen);
  	crypto_ablkcipher_set_flags(parent, crypto_blkcipher_get_flags(child) &
  					    CRYPTO_TFM_RES_MASK);
  	return err;
  }
  
  static void cryptd_blkcipher_crypt(struct ablkcipher_request *req,
  				   struct crypto_blkcipher *child,
  				   int err,
  				   int (*crypt)(struct blkcipher_desc *desc,
  						struct scatterlist *dst,
  						struct scatterlist *src,
  						unsigned int len))
  {
  	struct cryptd_blkcipher_request_ctx *rctx;

  	struct cryptd_blkcipher_ctx *ctx;
  	struct crypto_ablkcipher *tfm;

  	struct blkcipher_desc desc;

  	int refcnt;

  
  	rctx = ablkcipher_request_ctx(req);

  	if (unlikely(err == -EINPROGRESS))
  		goto out;

  
  	desc.tfm = child;
  	desc.info = req->info;
  	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
  
  	err = crypt(&desc, req->dst, req->src, req->nbytes);
  
  	req->base.complete = rctx->complete;

  out:

  	tfm = crypto_ablkcipher_reqtfm(req);
  	ctx = crypto_ablkcipher_ctx(tfm);
  	refcnt = atomic_read(&ctx->refcnt);

  	local_bh_disable();

  	rctx->complete(&req->base, err);

  	local_bh_enable();

  
  	if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_ablkcipher(tfm);

  }
  
  static void cryptd_blkcipher_encrypt(struct crypto_async_request *req, int err)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm);
  	struct crypto_blkcipher *child = ctx->child;
  
  	cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err,
  			       crypto_blkcipher_crt(child)->encrypt);
  }
  
  static void cryptd_blkcipher_decrypt(struct crypto_async_request *req, int err)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(req->tfm);
  	struct crypto_blkcipher *child = ctx->child;
  
  	cryptd_blkcipher_crypt(ablkcipher_request_cast(req), child, err,
  			       crypto_blkcipher_crt(child)->decrypt);
  }
  
  static int cryptd_blkcipher_enqueue(struct ablkcipher_request *req,

  				    crypto_completion_t compl)

  {
  	struct cryptd_blkcipher_request_ctx *rctx = ablkcipher_request_ctx(req);
  	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);

  	struct cryptd_queue *queue;

  	queue = cryptd_get_queue(crypto_ablkcipher_tfm(tfm));

  	rctx->complete = req->base.complete;

  	req->base.complete = compl;

  	return cryptd_enqueue_request(queue, &req->base);

  }
  
  static int cryptd_blkcipher_encrypt_enqueue(struct ablkcipher_request *req)
  {
  	return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_encrypt);
  }
  
  static int cryptd_blkcipher_decrypt_enqueue(struct ablkcipher_request *req)
  {
  	return cryptd_blkcipher_enqueue(req, cryptd_blkcipher_decrypt);
  }
  
  static int cryptd_blkcipher_init_tfm(struct crypto_tfm *tfm)
  {
  	struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
  	struct cryptd_instance_ctx *ictx = crypto_instance_ctx(inst);
  	struct crypto_spawn *spawn = &ictx->spawn;
  	struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
  	struct crypto_blkcipher *cipher;
  
  	cipher = crypto_spawn_blkcipher(spawn);
  	if (IS_ERR(cipher))
  		return PTR_ERR(cipher);
  
  	ctx->child = cipher;
  	tfm->crt_ablkcipher.reqsize =
  		sizeof(struct cryptd_blkcipher_request_ctx);
  	return 0;
  }
  
  static void cryptd_blkcipher_exit_tfm(struct crypto_tfm *tfm)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_tfm_ctx(tfm);

  
  	crypto_free_blkcipher(ctx->child);
  }

  static int cryptd_init_instance(struct crypto_instance *inst,
  				struct crypto_alg *alg)
  {
  	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
  		     "cryptd(%s)",
  		     alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
  		return -ENAMETOOLONG;
  
  	memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
  
  	inst->alg.cra_priority = alg->cra_priority + 50;
  	inst->alg.cra_blocksize = alg->cra_blocksize;
  	inst->alg.cra_alignmask = alg->cra_alignmask;
  
  	return 0;
  }

  static void *cryptd_alloc_instance(struct crypto_alg *alg, unsigned int head,
  				   unsigned int tail)

  {

  	char *p;

  	struct crypto_instance *inst;

  	int err;

  	p = kzalloc(head + sizeof(*inst) + tail, GFP_KERNEL);
  	if (!p)
  		return ERR_PTR(-ENOMEM);
  
  	inst = (void *)(p + head);

  	err = cryptd_init_instance(inst, alg);
  	if (err)

  		goto out_free_inst;

  out:

  	return p;

  
  out_free_inst:

  	kfree(p);
  	p = ERR_PTR(err);

  	goto out;
  }

  static int cryptd_create_blkcipher(struct crypto_template *tmpl,
  				   struct rtattr **tb,
  				   struct cryptd_queue *queue)

  {

  	struct cryptd_instance_ctx *ctx;

  	struct crypto_instance *inst;
  	struct crypto_alg *alg;

  	u32 type = CRYPTO_ALG_TYPE_BLKCIPHER;
  	u32 mask = CRYPTO_ALG_TYPE_MASK;

  	int err;

  	cryptd_check_internal(tb, &type, &mask);
  
  	alg = crypto_get_attr_alg(tb, type, mask);

  	if (IS_ERR(alg))

  		return PTR_ERR(alg);

  	inst = cryptd_alloc_instance(alg, 0, sizeof(*ctx));

  	err = PTR_ERR(inst);

  	if (IS_ERR(inst))
  		goto out_put_alg;

  	ctx = crypto_instance_ctx(inst);
  	ctx->queue = queue;
  
  	err = crypto_init_spawn(&ctx->spawn, alg, inst,
  				CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC);
  	if (err)
  		goto out_free_inst;

  	type = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC;
  	if (alg->cra_flags & CRYPTO_ALG_INTERNAL)
  		type |= CRYPTO_ALG_INTERNAL;
  	inst->alg.cra_flags = type;

  	inst->alg.cra_type = &crypto_ablkcipher_type;
  
  	inst->alg.cra_ablkcipher.ivsize = alg->cra_blkcipher.ivsize;
  	inst->alg.cra_ablkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
  	inst->alg.cra_ablkcipher.max_keysize = alg->cra_blkcipher.max_keysize;

  	inst->alg.cra_ablkcipher.geniv = alg->cra_blkcipher.geniv;

  	inst->alg.cra_ctxsize = sizeof(struct cryptd_blkcipher_ctx);
  
  	inst->alg.cra_init = cryptd_blkcipher_init_tfm;
  	inst->alg.cra_exit = cryptd_blkcipher_exit_tfm;
  
  	inst->alg.cra_ablkcipher.setkey = cryptd_blkcipher_setkey;
  	inst->alg.cra_ablkcipher.encrypt = cryptd_blkcipher_encrypt_enqueue;
  	inst->alg.cra_ablkcipher.decrypt = cryptd_blkcipher_decrypt_enqueue;

  	err = crypto_register_instance(tmpl, inst);
  	if (err) {
  		crypto_drop_spawn(&ctx->spawn);
  out_free_inst:
  		kfree(inst);
  	}

  out_put_alg:
  	crypto_mod_put(alg);

  	return err;

  }

  static int cryptd_skcipher_setkey(struct crypto_skcipher *parent,
  				  const u8 *key, unsigned int keylen)
  {
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(parent);
  	struct crypto_skcipher *child = ctx->child;
  	int err;
  
  	crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  	crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) &
  					 CRYPTO_TFM_REQ_MASK);
  	err = crypto_skcipher_setkey(child, key, keylen);
  	crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) &
  					  CRYPTO_TFM_RES_MASK);
  	return err;
  }
  
  static void cryptd_skcipher_complete(struct skcipher_request *req, int err)
  {
  	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  	struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
  	int refcnt = atomic_read(&ctx->refcnt);
  
  	local_bh_disable();
  	rctx->complete(&req->base, err);
  	local_bh_enable();
  
  	if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_skcipher(tfm);
  }
  
  static void cryptd_skcipher_encrypt(struct crypto_async_request *base,
  				    int err)
  {
  	struct skcipher_request *req = skcipher_request_cast(base);
  	struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
  	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  	struct crypto_skcipher *child = ctx->child;
  	SKCIPHER_REQUEST_ON_STACK(subreq, child);
  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;
  
  	skcipher_request_set_tfm(subreq, child);
  	skcipher_request_set_callback(subreq, CRYPTO_TFM_REQ_MAY_SLEEP,
  				      NULL, NULL);
  	skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
  				   req->iv);
  
  	err = crypto_skcipher_encrypt(subreq);
  	skcipher_request_zero(subreq);
  
  	req->base.complete = rctx->complete;
  
  out:
  	cryptd_skcipher_complete(req, err);
  }
  
  static void cryptd_skcipher_decrypt(struct crypto_async_request *base,
  				    int err)
  {
  	struct skcipher_request *req = skcipher_request_cast(base);
  	struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
  	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  	struct crypto_skcipher *child = ctx->child;
  	SKCIPHER_REQUEST_ON_STACK(subreq, child);
  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;
  
  	skcipher_request_set_tfm(subreq, child);
  	skcipher_request_set_callback(subreq, CRYPTO_TFM_REQ_MAY_SLEEP,
  				      NULL, NULL);
  	skcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
  				   req->iv);
  
  	err = crypto_skcipher_decrypt(subreq);
  	skcipher_request_zero(subreq);
  
  	req->base.complete = rctx->complete;
  
  out:
  	cryptd_skcipher_complete(req, err);
  }
  
  static int cryptd_skcipher_enqueue(struct skcipher_request *req,
  				   crypto_completion_t compl)
  {
  	struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
  	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  	struct cryptd_queue *queue;
  
  	queue = cryptd_get_queue(crypto_skcipher_tfm(tfm));
  	rctx->complete = req->base.complete;
  	req->base.complete = compl;
  
  	return cryptd_enqueue_request(queue, &req->base);
  }
  
  static int cryptd_skcipher_encrypt_enqueue(struct skcipher_request *req)
  {
  	return cryptd_skcipher_enqueue(req, cryptd_skcipher_encrypt);
  }
  
  static int cryptd_skcipher_decrypt_enqueue(struct skcipher_request *req)
  {
  	return cryptd_skcipher_enqueue(req, cryptd_skcipher_decrypt);
  }
  
  static int cryptd_skcipher_init_tfm(struct crypto_skcipher *tfm)
  {
  	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
  	struct skcipherd_instance_ctx *ictx = skcipher_instance_ctx(inst);
  	struct crypto_skcipher_spawn *spawn = &ictx->spawn;
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  	struct crypto_skcipher *cipher;
  
  	cipher = crypto_spawn_skcipher(spawn);
  	if (IS_ERR(cipher))
  		return PTR_ERR(cipher);
  
  	ctx->child = cipher;
  	crypto_skcipher_set_reqsize(
  		tfm, sizeof(struct cryptd_skcipher_request_ctx));
  	return 0;
  }
  
  static void cryptd_skcipher_exit_tfm(struct crypto_skcipher *tfm)
  {
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
  
  	crypto_free_skcipher(ctx->child);
  }
  
  static void cryptd_skcipher_free(struct skcipher_instance *inst)
  {
  	struct skcipherd_instance_ctx *ctx = skcipher_instance_ctx(inst);
  
  	crypto_drop_skcipher(&ctx->spawn);
  }
  
  static int cryptd_create_skcipher(struct crypto_template *tmpl,
  				  struct rtattr **tb,
  				  struct cryptd_queue *queue)
  {
  	struct skcipherd_instance_ctx *ctx;
  	struct skcipher_instance *inst;
  	struct skcipher_alg *alg;
  	const char *name;
  	u32 type;
  	u32 mask;
  	int err;
  
  	type = 0;
  	mask = CRYPTO_ALG_ASYNC;
  
  	cryptd_check_internal(tb, &type, &mask);
  
  	name = crypto_attr_alg_name(tb[1]);
  	if (IS_ERR(name))
  		return PTR_ERR(name);
  
  	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
  	if (!inst)
  		return -ENOMEM;
  
  	ctx = skcipher_instance_ctx(inst);
  	ctx->queue = queue;
  
  	crypto_set_skcipher_spawn(&ctx->spawn, skcipher_crypto_instance(inst));
  	err = crypto_grab_skcipher(&ctx->spawn, name, type, mask);
  	if (err)
  		goto out_free_inst;
  
  	alg = crypto_spawn_skcipher_alg(&ctx->spawn);
  	err = cryptd_init_instance(skcipher_crypto_instance(inst), &alg->base);
  	if (err)
  		goto out_drop_skcipher;
  
  	inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC |
  				   (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);
  
  	inst->alg.ivsize = crypto_skcipher_alg_ivsize(alg);
  	inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg);
  	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg);
  	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg);
  
  	inst->alg.base.cra_ctxsize = sizeof(struct cryptd_skcipher_ctx);
  
  	inst->alg.init = cryptd_skcipher_init_tfm;
  	inst->alg.exit = cryptd_skcipher_exit_tfm;
  
  	inst->alg.setkey = cryptd_skcipher_setkey;
  	inst->alg.encrypt = cryptd_skcipher_encrypt_enqueue;
  	inst->alg.decrypt = cryptd_skcipher_decrypt_enqueue;
  
  	inst->free = cryptd_skcipher_free;
  
  	err = skcipher_register_instance(tmpl, inst);
  	if (err) {
  out_drop_skcipher:
  		crypto_drop_skcipher(&ctx->spawn);
  out_free_inst:
  		kfree(inst);
  	}
  	return err;
  }

  static int cryptd_hash_init_tfm(struct crypto_tfm *tfm)
  {
  	struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);

  	struct hashd_instance_ctx *ictx = crypto_instance_ctx(inst);
  	struct crypto_shash_spawn *spawn = &ictx->spawn;

  	struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(tfm);

  	struct crypto_shash *hash;

  	hash = crypto_spawn_shash(spawn);
  	if (IS_ERR(hash))
  		return PTR_ERR(hash);

  	ctx->child = hash;

  	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
  				 sizeof(struct cryptd_hash_request_ctx) +
  				 crypto_shash_descsize(hash));

  	return 0;
  }
  
  static void cryptd_hash_exit_tfm(struct crypto_tfm *tfm)
  {
  	struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(tfm);

  	crypto_free_shash(ctx->child);

  }
  
  static int cryptd_hash_setkey(struct crypto_ahash *parent,
  				   const u8 *key, unsigned int keylen)
  {
  	struct cryptd_hash_ctx *ctx   = crypto_ahash_ctx(parent);

  	struct crypto_shash *child = ctx->child;

  	int err;

  	crypto_shash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
  	crypto_shash_set_flags(child, crypto_ahash_get_flags(parent) &
  				      CRYPTO_TFM_REQ_MASK);
  	err = crypto_shash_setkey(child, key, keylen);
  	crypto_ahash_set_flags(parent, crypto_shash_get_flags(child) &
  				       CRYPTO_TFM_RES_MASK);

  	return err;
  }
  
  static int cryptd_hash_enqueue(struct ahash_request *req,

  				crypto_completion_t compl)

  {
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);

  	struct cryptd_queue *queue =
  		cryptd_get_queue(crypto_ahash_tfm(tfm));

  
  	rctx->complete = req->base.complete;

  	req->base.complete = compl;

  	return cryptd_enqueue_request(queue, &req->base);

  }

  static void cryptd_hash_complete(struct ahash_request *req, int err)
  {
  	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  	struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(tfm);
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  	int refcnt = atomic_read(&ctx->refcnt);
  
  	local_bh_disable();
  	rctx->complete(&req->base, err);
  	local_bh_enable();
  
  	if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_ahash(tfm);
  }

  static void cryptd_hash_init(struct crypto_async_request *req_async, int err)
  {

  	struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
  	struct crypto_shash *child = ctx->child;
  	struct ahash_request *req = ahash_request_cast(req_async);
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  	struct shash_desc *desc = &rctx->desc;

  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;

  	desc->tfm = child;
  	desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;

  	err = crypto_shash_init(desc);

  
  	req->base.complete = rctx->complete;
  
  out:

  	cryptd_hash_complete(req, err);

  }
  
  static int cryptd_hash_init_enqueue(struct ahash_request *req)
  {
  	return cryptd_hash_enqueue(req, cryptd_hash_init);
  }
  
  static void cryptd_hash_update(struct crypto_async_request *req_async, int err)
  {

  	struct ahash_request *req = ahash_request_cast(req_async);

  	struct cryptd_hash_request_ctx *rctx;

  
  	rctx = ahash_request_ctx(req);
  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;

  	err = shash_ahash_update(req, &rctx->desc);

  
  	req->base.complete = rctx->complete;
  
  out:

  	cryptd_hash_complete(req, err);

  }
  
  static int cryptd_hash_update_enqueue(struct ahash_request *req)
  {
  	return cryptd_hash_enqueue(req, cryptd_hash_update);
  }
  
  static void cryptd_hash_final(struct crypto_async_request *req_async, int err)
  {

  	struct ahash_request *req = ahash_request_cast(req_async);
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);

  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;

  	err = crypto_shash_final(&rctx->desc, req->result);

  
  	req->base.complete = rctx->complete;
  
  out:

  	cryptd_hash_complete(req, err);

  }
  
  static int cryptd_hash_final_enqueue(struct ahash_request *req)
  {
  	return cryptd_hash_enqueue(req, cryptd_hash_final);
  }

  static void cryptd_hash_finup(struct crypto_async_request *req_async, int err)
  {
  	struct ahash_request *req = ahash_request_cast(req_async);
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;
  
  	err = shash_ahash_finup(req, &rctx->desc);
  
  	req->base.complete = rctx->complete;
  
  out:

  	cryptd_hash_complete(req, err);

  }
  
  static int cryptd_hash_finup_enqueue(struct ahash_request *req)
  {
  	return cryptd_hash_enqueue(req, cryptd_hash_finup);
  }

  static void cryptd_hash_digest(struct crypto_async_request *req_async, int err)
  {

  	struct cryptd_hash_ctx *ctx = crypto_tfm_ctx(req_async->tfm);
  	struct crypto_shash *child = ctx->child;
  	struct ahash_request *req = ahash_request_cast(req_async);
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  	struct shash_desc *desc = &rctx->desc;

  
  	if (unlikely(err == -EINPROGRESS))
  		goto out;

  	desc->tfm = child;
  	desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;

  	err = shash_ahash_digest(req, desc);

  
  	req->base.complete = rctx->complete;
  
  out:

  	cryptd_hash_complete(req, err);

  }
  
  static int cryptd_hash_digest_enqueue(struct ahash_request *req)
  {
  	return cryptd_hash_enqueue(req, cryptd_hash_digest);
  }

  static int cryptd_hash_export(struct ahash_request *req, void *out)
  {
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  
  	return crypto_shash_export(&rctx->desc, out);
  }
  
  static int cryptd_hash_import(struct ahash_request *req, const void *in)
  {

  	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  	struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(tfm);
  	struct shash_desc *desc = cryptd_shash_desc(req);
  
  	desc->tfm = ctx->child;
  	desc->flags = req->base.flags;

  	return crypto_shash_import(desc, in);

  }

  static int cryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
  			      struct cryptd_queue *queue)

  {

  	struct hashd_instance_ctx *ctx;

  	struct ahash_instance *inst;

  	struct shash_alg *salg;

  	struct crypto_alg *alg;

  	u32 type = 0;
  	u32 mask = 0;

  	int err;

  	cryptd_check_internal(tb, &type, &mask);
  
  	salg = shash_attr_alg(tb[1], type, mask);

  	if (IS_ERR(salg))

  		return PTR_ERR(salg);

  	alg = &salg->base;

  	inst = cryptd_alloc_instance(alg, ahash_instance_headroom(),
  				     sizeof(*ctx));

  	err = PTR_ERR(inst);

  	if (IS_ERR(inst))
  		goto out_put_alg;

  	ctx = ahash_instance_ctx(inst);

  	ctx->queue = queue;

  	err = crypto_init_shash_spawn(&ctx->spawn, salg,
  				      ahash_crypto_instance(inst));

  	if (err)
  		goto out_free_inst;

  	inst->alg.halg.base.cra_flags = CRYPTO_ALG_ASYNC |
  		(alg->cra_flags & (CRYPTO_ALG_INTERNAL |
  				   CRYPTO_ALG_OPTIONAL_KEY));

  	inst->alg.halg.digestsize = salg->digestsize;

  	inst->alg.halg.statesize = salg->statesize;

  	inst->alg.halg.base.cra_ctxsize = sizeof(struct cryptd_hash_ctx);

  	inst->alg.halg.base.cra_init = cryptd_hash_init_tfm;
  	inst->alg.halg.base.cra_exit = cryptd_hash_exit_tfm;

  	inst->alg.init   = cryptd_hash_init_enqueue;
  	inst->alg.update = cryptd_hash_update_enqueue;
  	inst->alg.final  = cryptd_hash_final_enqueue;

  	inst->alg.finup  = cryptd_hash_finup_enqueue;
  	inst->alg.export = cryptd_hash_export;
  	inst->alg.import = cryptd_hash_import;

  	if (crypto_shash_alg_has_setkey(salg))
  		inst->alg.setkey = cryptd_hash_setkey;

  	inst->alg.digest = cryptd_hash_digest_enqueue;

  	err = ahash_register_instance(tmpl, inst);

  	if (err) {
  		crypto_drop_shash(&ctx->spawn);
  out_free_inst:
  		kfree(inst);
  	}

  out_put_alg:
  	crypto_mod_put(alg);

  	return err;

  }

  static int cryptd_aead_setkey(struct crypto_aead *parent,
  			      const u8 *key, unsigned int keylen)
  {
  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(parent);
  	struct crypto_aead *child = ctx->child;
  
  	return crypto_aead_setkey(child, key, keylen);
  }
  
  static int cryptd_aead_setauthsize(struct crypto_aead *parent,
  				   unsigned int authsize)
  {
  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(parent);
  	struct crypto_aead *child = ctx->child;
  
  	return crypto_aead_setauthsize(child, authsize);
  }

  static void cryptd_aead_crypt(struct aead_request *req,
  			struct crypto_aead *child,
  			int err,
  			int (*crypt)(struct aead_request *req))
  {
  	struct cryptd_aead_request_ctx *rctx;

  	struct cryptd_aead_ctx *ctx;

  	crypto_completion_t compl;

  	struct crypto_aead *tfm;
  	int refcnt;

  	rctx = aead_request_ctx(req);

  	compl = rctx->complete;

  	tfm = crypto_aead_reqtfm(req);

  	if (unlikely(err == -EINPROGRESS))
  		goto out;
  	aead_request_set_tfm(req, child);
  	err = crypt( req );

  out:

  	ctx = crypto_aead_ctx(tfm);
  	refcnt = atomic_read(&ctx->refcnt);

  	local_bh_disable();

  	compl(&req->base, err);

  	local_bh_enable();

  
  	if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_aead(tfm);

  }
  
  static void cryptd_aead_encrypt(struct crypto_async_request *areq, int err)
  {
  	struct cryptd_aead_ctx *ctx = crypto_tfm_ctx(areq->tfm);
  	struct crypto_aead *child = ctx->child;
  	struct aead_request *req;
  
  	req = container_of(areq, struct aead_request, base);

  	cryptd_aead_crypt(req, child, err, crypto_aead_alg(child)->encrypt);

  }
  
  static void cryptd_aead_decrypt(struct crypto_async_request *areq, int err)
  {
  	struct cryptd_aead_ctx *ctx = crypto_tfm_ctx(areq->tfm);
  	struct crypto_aead *child = ctx->child;
  	struct aead_request *req;
  
  	req = container_of(areq, struct aead_request, base);

  	cryptd_aead_crypt(req, child, err, crypto_aead_alg(child)->decrypt);

  }
  
  static int cryptd_aead_enqueue(struct aead_request *req,

  				    crypto_completion_t compl)

  {
  	struct cryptd_aead_request_ctx *rctx = aead_request_ctx(req);
  	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
  	struct cryptd_queue *queue = cryptd_get_queue(crypto_aead_tfm(tfm));
  
  	rctx->complete = req->base.complete;

  	req->base.complete = compl;

  	return cryptd_enqueue_request(queue, &req->base);
  }
  
  static int cryptd_aead_encrypt_enqueue(struct aead_request *req)
  {
  	return cryptd_aead_enqueue(req, cryptd_aead_encrypt );
  }
  
  static int cryptd_aead_decrypt_enqueue(struct aead_request *req)
  {
  	return cryptd_aead_enqueue(req, cryptd_aead_decrypt );
  }

  static int cryptd_aead_init_tfm(struct crypto_aead *tfm)

  {

  	struct aead_instance *inst = aead_alg_instance(tfm);
  	struct aead_instance_ctx *ictx = aead_instance_ctx(inst);

  	struct crypto_aead_spawn *spawn = &ictx->aead_spawn;

  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(tfm);

  	struct crypto_aead *cipher;
  
  	cipher = crypto_spawn_aead(spawn);
  	if (IS_ERR(cipher))
  		return PTR_ERR(cipher);

  	ctx->child = cipher;

  	crypto_aead_set_reqsize(
  		tfm, max((unsigned)sizeof(struct cryptd_aead_request_ctx),
  			 crypto_aead_reqsize(cipher)));

  	return 0;
  }

  static void cryptd_aead_exit_tfm(struct crypto_aead *tfm)

  {

  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(tfm);

  	crypto_free_aead(ctx->child);
  }
  
  static int cryptd_create_aead(struct crypto_template *tmpl,
  		              struct rtattr **tb,
  			      struct cryptd_queue *queue)
  {
  	struct aead_instance_ctx *ctx;

  	struct aead_instance *inst;
  	struct aead_alg *alg;

  	const char *name;
  	u32 type = 0;

  	u32 mask = CRYPTO_ALG_ASYNC;

  	int err;

  	cryptd_check_internal(tb, &type, &mask);

  	name = crypto_attr_alg_name(tb[1]);
  	if (IS_ERR(name))
  		return PTR_ERR(name);

  	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
  	if (!inst)
  		return -ENOMEM;

  	ctx = aead_instance_ctx(inst);

  	ctx->queue = queue;

  	crypto_set_aead_spawn(&ctx->aead_spawn, aead_crypto_instance(inst));

  	err = crypto_grab_aead(&ctx->aead_spawn, name, type, mask);

  	if (err)
  		goto out_free_inst;

  	alg = crypto_spawn_aead_alg(&ctx->aead_spawn);
  	err = cryptd_init_instance(aead_crypto_instance(inst), &alg->base);

  	if (err)
  		goto out_drop_aead;

  	inst->alg.base.cra_flags = CRYPTO_ALG_ASYNC |

  				   (alg->base.cra_flags & CRYPTO_ALG_INTERNAL);

  	inst->alg.base.cra_ctxsize = sizeof(struct cryptd_aead_ctx);

  	inst->alg.ivsize = crypto_aead_alg_ivsize(alg);
  	inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
  
  	inst->alg.init = cryptd_aead_init_tfm;
  	inst->alg.exit = cryptd_aead_exit_tfm;
  	inst->alg.setkey = cryptd_aead_setkey;
  	inst->alg.setauthsize = cryptd_aead_setauthsize;
  	inst->alg.encrypt = cryptd_aead_encrypt_enqueue;
  	inst->alg.decrypt = cryptd_aead_decrypt_enqueue;
  
  	err = aead_register_instance(tmpl, inst);

  	if (err) {

  out_drop_aead:
  		crypto_drop_aead(&ctx->aead_spawn);

  out_free_inst:
  		kfree(inst);
  	}

  	return err;
  }

  static struct cryptd_queue queue;

  static int cryptd_create(struct crypto_template *tmpl, struct rtattr **tb)

  {
  	struct crypto_attr_type *algt;
  
  	algt = crypto_get_attr_type(tb);
  	if (IS_ERR(algt))

  		return PTR_ERR(algt);

  
  	switch (algt->type & algt->mask & CRYPTO_ALG_TYPE_MASK) {
  	case CRYPTO_ALG_TYPE_BLKCIPHER:

  		if ((algt->type & CRYPTO_ALG_TYPE_MASK) ==
  		    CRYPTO_ALG_TYPE_BLKCIPHER)
  			return cryptd_create_blkcipher(tmpl, tb, &queue);
  
  		return cryptd_create_skcipher(tmpl, tb, &queue);

  	case CRYPTO_ALG_TYPE_DIGEST:

  		return cryptd_create_hash(tmpl, tb, &queue);

  	case CRYPTO_ALG_TYPE_AEAD:
  		return cryptd_create_aead(tmpl, tb, &queue);

  	}

  	return -EINVAL;

  }
  
  static void cryptd_free(struct crypto_instance *inst)
  {
  	struct cryptd_instance_ctx *ctx = crypto_instance_ctx(inst);

  	struct hashd_instance_ctx *hctx = crypto_instance_ctx(inst);

  	struct aead_instance_ctx *aead_ctx = crypto_instance_ctx(inst);

  
  	switch (inst->alg.cra_flags & CRYPTO_ALG_TYPE_MASK) {
  	case CRYPTO_ALG_TYPE_AHASH:
  		crypto_drop_shash(&hctx->spawn);
  		kfree(ahash_instance(inst));
  		return;

  	case CRYPTO_ALG_TYPE_AEAD:

  		crypto_drop_aead(&aead_ctx->aead_spawn);
  		kfree(aead_instance(inst));

  		return;
  	default:
  		crypto_drop_spawn(&ctx->spawn);
  		kfree(inst);

  	}

  }
  
  static struct crypto_template cryptd_tmpl = {
  	.name = "cryptd",

  	.create = cryptd_create,

  	.free = cryptd_free,
  	.module = THIS_MODULE,
  };

  struct cryptd_ablkcipher *cryptd_alloc_ablkcipher(const char *alg_name,
  						  u32 type, u32 mask)
  {
  	char cryptd_alg_name[CRYPTO_MAX_ALG_NAME];

  	struct cryptd_blkcipher_ctx *ctx;

  	struct crypto_tfm *tfm;

  
  	if (snprintf(cryptd_alg_name, CRYPTO_MAX_ALG_NAME,
  		     "cryptd(%s)", alg_name) >= CRYPTO_MAX_ALG_NAME)
  		return ERR_PTR(-EINVAL);

  	type = crypto_skcipher_type(type);

  	mask &= ~CRYPTO_ALG_TYPE_MASK;
  	mask |= (CRYPTO_ALG_GENIV | CRYPTO_ALG_TYPE_BLKCIPHER_MASK);
  	tfm = crypto_alloc_base(cryptd_alg_name, type, mask);

  	if (IS_ERR(tfm))
  		return ERR_CAST(tfm);

  	if (tfm->__crt_alg->cra_module != THIS_MODULE) {
  		crypto_free_tfm(tfm);

  		return ERR_PTR(-EINVAL);
  	}

  	ctx = crypto_tfm_ctx(tfm);
  	atomic_set(&ctx->refcnt, 1);

  	return __cryptd_ablkcipher_cast(__crypto_ablkcipher_cast(tfm));

  }
  EXPORT_SYMBOL_GPL(cryptd_alloc_ablkcipher);
  
  struct crypto_blkcipher *cryptd_ablkcipher_child(struct cryptd_ablkcipher *tfm)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(&tfm->base);
  	return ctx->child;
  }
  EXPORT_SYMBOL_GPL(cryptd_ablkcipher_child);

  bool cryptd_ablkcipher_queued(struct cryptd_ablkcipher *tfm)
  {
  	struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(&tfm->base);
  
  	return atomic_read(&ctx->refcnt) - 1;
  }
  EXPORT_SYMBOL_GPL(cryptd_ablkcipher_queued);

  void cryptd_free_ablkcipher(struct cryptd_ablkcipher *tfm)
  {

  	struct cryptd_blkcipher_ctx *ctx = crypto_ablkcipher_ctx(&tfm->base);
  
  	if (atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_ablkcipher(&tfm->base);

  }
  EXPORT_SYMBOL_GPL(cryptd_free_ablkcipher);

  struct cryptd_skcipher *cryptd_alloc_skcipher(const char *alg_name,
  					      u32 type, u32 mask)
  {
  	char cryptd_alg_name[CRYPTO_MAX_ALG_NAME];
  	struct cryptd_skcipher_ctx *ctx;
  	struct crypto_skcipher *tfm;
  
  	if (snprintf(cryptd_alg_name, CRYPTO_MAX_ALG_NAME,
  		     "cryptd(%s)", alg_name) >= CRYPTO_MAX_ALG_NAME)
  		return ERR_PTR(-EINVAL);
  
  	tfm = crypto_alloc_skcipher(cryptd_alg_name, type, mask);
  	if (IS_ERR(tfm))
  		return ERR_CAST(tfm);
  
  	if (tfm->base.__crt_alg->cra_module != THIS_MODULE) {
  		crypto_free_skcipher(tfm);
  		return ERR_PTR(-EINVAL);
  	}
  
  	ctx = crypto_skcipher_ctx(tfm);
  	atomic_set(&ctx->refcnt, 1);
  
  	return container_of(tfm, struct cryptd_skcipher, base);
  }
  EXPORT_SYMBOL_GPL(cryptd_alloc_skcipher);
  
  struct crypto_skcipher *cryptd_skcipher_child(struct cryptd_skcipher *tfm)
  {
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base);
  
  	return ctx->child;
  }
  EXPORT_SYMBOL_GPL(cryptd_skcipher_child);
  
  bool cryptd_skcipher_queued(struct cryptd_skcipher *tfm)
  {
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base);
  
  	return atomic_read(&ctx->refcnt) - 1;
  }
  EXPORT_SYMBOL_GPL(cryptd_skcipher_queued);
  
  void cryptd_free_skcipher(struct cryptd_skcipher *tfm)
  {
  	struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(&tfm->base);
  
  	if (atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_skcipher(&tfm->base);
  }
  EXPORT_SYMBOL_GPL(cryptd_free_skcipher);

  struct cryptd_ahash *cryptd_alloc_ahash(const char *alg_name,
  					u32 type, u32 mask)
  {
  	char cryptd_alg_name[CRYPTO_MAX_ALG_NAME];

  	struct cryptd_hash_ctx *ctx;

  	struct crypto_ahash *tfm;
  
  	if (snprintf(cryptd_alg_name, CRYPTO_MAX_ALG_NAME,
  		     "cryptd(%s)", alg_name) >= CRYPTO_MAX_ALG_NAME)
  		return ERR_PTR(-EINVAL);
  	tfm = crypto_alloc_ahash(cryptd_alg_name, type, mask);
  	if (IS_ERR(tfm))
  		return ERR_CAST(tfm);
  	if (tfm->base.__crt_alg->cra_module != THIS_MODULE) {
  		crypto_free_ahash(tfm);
  		return ERR_PTR(-EINVAL);
  	}

  	ctx = crypto_ahash_ctx(tfm);
  	atomic_set(&ctx->refcnt, 1);

  	return __cryptd_ahash_cast(tfm);
  }
  EXPORT_SYMBOL_GPL(cryptd_alloc_ahash);
  
  struct crypto_shash *cryptd_ahash_child(struct cryptd_ahash *tfm)
  {
  	struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base);
  
  	return ctx->child;
  }
  EXPORT_SYMBOL_GPL(cryptd_ahash_child);

  struct shash_desc *cryptd_shash_desc(struct ahash_request *req)
  {
  	struct cryptd_hash_request_ctx *rctx = ahash_request_ctx(req);
  	return &rctx->desc;
  }
  EXPORT_SYMBOL_GPL(cryptd_shash_desc);

  bool cryptd_ahash_queued(struct cryptd_ahash *tfm)
  {
  	struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base);
  
  	return atomic_read(&ctx->refcnt) - 1;
  }
  EXPORT_SYMBOL_GPL(cryptd_ahash_queued);

  void cryptd_free_ahash(struct cryptd_ahash *tfm)
  {

  	struct cryptd_hash_ctx *ctx = crypto_ahash_ctx(&tfm->base);
  
  	if (atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_ahash(&tfm->base);

  }
  EXPORT_SYMBOL_GPL(cryptd_free_ahash);

  struct cryptd_aead *cryptd_alloc_aead(const char *alg_name,
  						  u32 type, u32 mask)
  {
  	char cryptd_alg_name[CRYPTO_MAX_ALG_NAME];

  	struct cryptd_aead_ctx *ctx;

  	struct crypto_aead *tfm;
  
  	if (snprintf(cryptd_alg_name, CRYPTO_MAX_ALG_NAME,
  		     "cryptd(%s)", alg_name) >= CRYPTO_MAX_ALG_NAME)
  		return ERR_PTR(-EINVAL);
  	tfm = crypto_alloc_aead(cryptd_alg_name, type, mask);
  	if (IS_ERR(tfm))
  		return ERR_CAST(tfm);
  	if (tfm->base.__crt_alg->cra_module != THIS_MODULE) {
  		crypto_free_aead(tfm);
  		return ERR_PTR(-EINVAL);
  	}

  
  	ctx = crypto_aead_ctx(tfm);
  	atomic_set(&ctx->refcnt, 1);

  	return __cryptd_aead_cast(tfm);
  }
  EXPORT_SYMBOL_GPL(cryptd_alloc_aead);
  
  struct crypto_aead *cryptd_aead_child(struct cryptd_aead *tfm)
  {
  	struct cryptd_aead_ctx *ctx;
  	ctx = crypto_aead_ctx(&tfm->base);
  	return ctx->child;
  }
  EXPORT_SYMBOL_GPL(cryptd_aead_child);

  bool cryptd_aead_queued(struct cryptd_aead *tfm)
  {
  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base);
  
  	return atomic_read(&ctx->refcnt) - 1;
  }
  EXPORT_SYMBOL_GPL(cryptd_aead_queued);

  void cryptd_free_aead(struct cryptd_aead *tfm)
  {

  	struct cryptd_aead_ctx *ctx = crypto_aead_ctx(&tfm->base);
  
  	if (atomic_dec_and_test(&ctx->refcnt))
  		crypto_free_aead(&tfm->base);

  }
  EXPORT_SYMBOL_GPL(cryptd_free_aead);

  static int __init cryptd_init(void)
  {
  	int err;

  	err = cryptd_init_queue(&queue, CRYPTD_MAX_CPU_QLEN);

  	if (err)
  		return err;
  
  	err = crypto_register_template(&cryptd_tmpl);
  	if (err)

  		cryptd_fini_queue(&queue);

  
  	return err;
  }
  
  static void __exit cryptd_exit(void)
  {

  	cryptd_fini_queue(&queue);

  	crypto_unregister_template(&cryptd_tmpl);
  }

  subsys_initcall(cryptd_init);

  module_exit(cryptd_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Software async crypto daemon");

  MODULE_ALIAS_CRYPTO("cryptd");