Commit 3860642e authored by Herbert Xu's avatar Herbert Xu
Browse files

crypto: api - Move alg destroy work from instance to template 



Commit 9ae4577b ("crypto: api - Use work queue in
crypto_destroy_instance") introduced a work struct to free an
instance after the last user goes away.

Move the delayed work from the instance into its template so that
when the template is unregistered it can ensure that all its
instances have been freed before returning.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 1ddaff40

crypto/algapi.c

+27 −8
Original line number Diff line number Diff line
@@ -71,12 +71,23 @@ static void crypto_free_instance(struct crypto_instance *inst) 


static void crypto_destroy_instance_workfn(struct work_struct *w)

{

	struct crypto_instance *inst = container_of(w, struct crypto_instance,

	struct crypto_template *tmpl = container_of(w, struct crypto_template,

						    free_work);

	struct crypto_template *tmpl = inst->tmpl;

	struct crypto_instance *inst;

	struct hlist_node *n;

	HLIST_HEAD(list);



	down_write(&crypto_alg_sem);

	hlist_for_each_entry_safe(inst, n, &tmpl->dead, list) {

		if (refcount_read(&inst->alg.cra_refcnt) != -1)

			continue;

		hlist_del(&inst->list);

		hlist_add_head(&inst->list, &list);

	}

	up_write(&crypto_alg_sem);



	hlist_for_each_entry_safe(inst, n, &list, list)

		crypto_free_instance(inst);

	crypto_tmpl_put(tmpl);

}



static void crypto_destroy_instance(struct crypto_alg *alg)
@@ -84,9 +95,10 @@ static void crypto_destroy_instance(struct crypto_alg *alg) 
	struct crypto_instance *inst = container_of(alg,

						    struct crypto_instance,

						    alg);

	struct crypto_template *tmpl = inst->tmpl;



	INIT_WORK(&inst->free_work, crypto_destroy_instance_workfn);

	schedule_work(&inst->free_work);

	refcount_set(&alg->cra_refcnt, -1);

	schedule_work(&tmpl->free_work);

}



/*
@@ -132,14 +144,17 @@ static void crypto_remove_instance(struct crypto_instance *inst, 


	inst->alg.cra_flags |= CRYPTO_ALG_DEAD;



	if (!tmpl || !crypto_tmpl_get(tmpl))

	if (!tmpl)

		return;



	list_move(&inst->alg.cra_list, list);

	list_del_init(&inst->alg.cra_list);

	hlist_del(&inst->list);

	hlist_add_head(&inst->list, &tmpl->dead);

	inst->alg.cra_destroy = crypto_destroy_instance;



	BUG_ON(!list_empty(&inst->alg.cra_users));



	crypto_alg_put(&inst->alg);

}



/*
@@ -504,6 +519,8 @@ int crypto_register_template(struct crypto_template *tmpl) 
	struct crypto_template *q;

	int err = -EEXIST;



	INIT_WORK(&tmpl->free_work, crypto_destroy_instance_workfn);



	down_write(&crypto_alg_sem);



	crypto_check_module_sig(tmpl->module);
@@ -565,6 +582,8 @@ void crypto_unregister_template(struct crypto_template *tmpl) 
		crypto_free_instance(inst);

	}

	crypto_remove_final(&users);



	flush_work(&tmpl->free_work);

}

EXPORT_SYMBOL_GPL(crypto_unregister_template);

include/crypto/algapi.h

+3 −2
Original line number Diff line number Diff line
@@ -68,16 +68,17 @@ struct crypto_instance { 
		struct crypto_spawn *spawns;

	};



	struct work_struct free_work;



	void *__ctx[] CRYPTO_MINALIGN_ATTR;

};



struct crypto_template {

	struct list_head list;

	struct hlist_head instances;

	struct hlist_head dead;

	struct module *module;



	struct work_struct free_work;



	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);



	char name[CRYPTO_MAX_ALG_NAME];