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Commit 9534d671 authored by Herbert Xu's avatar Herbert Xu
Browse files

drbd: Use shash and ahash 



This patch replaces uses of the long obsolete hash interface with
either shash (for non-SG users) or ahash.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 17bc1970

drivers/block/drbd/drbd_int.h

+8 −8
Original line number Diff line number Diff line
@@ -26,13 +26,13 @@ 
#ifndef _DRBD_INT_H

#define _DRBD_INT_H



#include <crypto/hash.h>

#include <linux/compiler.h>

#include <linux/types.h>

#include <linux/list.h>

#include <linux/sched.h>

#include <linux/bitops.h>

#include <linux/slab.h>

#include <linux/crypto.h>

#include <linux/ratelimit.h>

#include <linux/tcp.h>

#include <linux/mutex.h>
@@ -724,11 +724,11 @@ struct drbd_connection { 


	struct list_head transfer_log;	/* all requests not yet fully processed */



	struct crypto_hash *cram_hmac_tfm;

	struct crypto_hash *integrity_tfm;  /* checksums we compute, updates protected by connection->data->mutex */

	struct crypto_hash *peer_integrity_tfm;  /* checksums we verify, only accessed from receiver thread  */

	struct crypto_hash *csums_tfm;

	struct crypto_hash *verify_tfm;

	struct crypto_shash *cram_hmac_tfm;

	struct crypto_ahash *integrity_tfm;  /* checksums we compute, updates protected by connection->data->mutex */

	struct crypto_ahash *peer_integrity_tfm;  /* checksums we verify, only accessed from receiver thread  */

	struct crypto_ahash *csums_tfm;

	struct crypto_ahash *verify_tfm;

	void *int_dig_in;

	void *int_dig_vv;
@@ -1524,8 +1524,8 @@ static inline void ov_out_of_sync_print(struct drbd_device *device) 
}





extern void drbd_csum_bio(struct crypto_hash *, struct bio *, void *);

extern void drbd_csum_ee(struct crypto_hash *, struct drbd_peer_request *, void *);

extern void drbd_csum_bio(struct crypto_ahash *, struct bio *, void *);

extern void drbd_csum_ee(struct crypto_ahash *, struct drbd_peer_request *, void *);

/* worker callbacks */

extern int w_e_end_data_req(struct drbd_work *, int);

extern int w_e_end_rsdata_req(struct drbd_work *, int);

drivers/block/drbd/drbd_main.c

+8 −8
Original line number Diff line number Diff line
@@ -1340,7 +1340,7 @@ void drbd_send_ack_dp(struct drbd_peer_device *peer_device, enum drbd_packet cmd 
		      struct p_data *dp, int data_size)

{

	if (peer_device->connection->peer_integrity_tfm)

		data_size -= crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm);

		data_size -= crypto_ahash_digestsize(peer_device->connection->peer_integrity_tfm);

	_drbd_send_ack(peer_device, cmd, dp->sector, cpu_to_be32(data_size),

		       dp->block_id);

}
@@ -1629,7 +1629,7 @@ int drbd_send_dblock(struct drbd_peer_device *peer_device, struct drbd_request * 
	sock = &peer_device->connection->data;

	p = drbd_prepare_command(peer_device, sock);

	digest_size = peer_device->connection->integrity_tfm ?

		      crypto_hash_digestsize(peer_device->connection->integrity_tfm) : 0;

		      crypto_ahash_digestsize(peer_device->connection->integrity_tfm) : 0;



	if (!p)

		return -EIO;
@@ -1718,7 +1718,7 @@ int drbd_send_block(struct drbd_peer_device *peer_device, enum drbd_packet cmd, 
	p = drbd_prepare_command(peer_device, sock);



	digest_size = peer_device->connection->integrity_tfm ?

		      crypto_hash_digestsize(peer_device->connection->integrity_tfm) : 0;

		      crypto_ahash_digestsize(peer_device->connection->integrity_tfm) : 0;



	if (!p)

		return -EIO;
@@ -2498,11 +2498,11 @@ void conn_free_crypto(struct drbd_connection *connection) 
{

	drbd_free_sock(connection);



	crypto_free_hash(connection->csums_tfm);

	crypto_free_hash(connection->verify_tfm);

	crypto_free_hash(connection->cram_hmac_tfm);

	crypto_free_hash(connection->integrity_tfm);

	crypto_free_hash(connection->peer_integrity_tfm);

	crypto_free_ahash(connection->csums_tfm);

	crypto_free_ahash(connection->verify_tfm);

	crypto_free_shash(connection->cram_hmac_tfm);

	crypto_free_ahash(connection->integrity_tfm);

	crypto_free_ahash(connection->peer_integrity_tfm);

	kfree(connection->int_dig_in);

	kfree(connection->int_dig_vv);

drivers/block/drbd/drbd_nl.c

+37 −22
Original line number Diff line number Diff line
@@ -2160,19 +2160,34 @@ check_net_options(struct drbd_connection *connection, struct net_conf *new_net_c 
}



struct crypto {

	struct crypto_hash *verify_tfm;

	struct crypto_hash *csums_tfm;

	struct crypto_hash *cram_hmac_tfm;

	struct crypto_hash *integrity_tfm;

	struct crypto_ahash *verify_tfm;

	struct crypto_ahash *csums_tfm;

	struct crypto_shash *cram_hmac_tfm;

	struct crypto_ahash *integrity_tfm;

};



static int

alloc_hash(struct crypto_hash **tfm, char *tfm_name, int err_alg)

alloc_shash(struct crypto_shash **tfm, char *tfm_name, int err_alg)

{

	if (!tfm_name[0])

		return NO_ERROR;



	*tfm = crypto_alloc_hash(tfm_name, 0, CRYPTO_ALG_ASYNC);

	*tfm = crypto_alloc_shash(tfm_name, 0, 0);

	if (IS_ERR(*tfm)) {

		*tfm = NULL;

		return err_alg;

	}



	return NO_ERROR;

}



static int

alloc_ahash(struct crypto_ahash **tfm, char *tfm_name, int err_alg)

{

	if (!tfm_name[0])

		return NO_ERROR;



	*tfm = crypto_alloc_ahash(tfm_name, 0, CRYPTO_ALG_ASYNC);

	if (IS_ERR(*tfm)) {

		*tfm = NULL;

		return err_alg;
@@ -2187,15 +2202,15 @@ alloc_crypto(struct crypto *crypto, struct net_conf *new_net_conf) 
	char hmac_name[CRYPTO_MAX_ALG_NAME];

	enum drbd_ret_code rv;



	rv = alloc_hash(&crypto->csums_tfm, new_net_conf->csums_alg,

	rv = alloc_ahash(&crypto->csums_tfm, new_net_conf->csums_alg,

			 ERR_CSUMS_ALG);

	if (rv != NO_ERROR)

		return rv;

	rv = alloc_hash(&crypto->verify_tfm, new_net_conf->verify_alg,

	rv = alloc_ahash(&crypto->verify_tfm, new_net_conf->verify_alg,

			 ERR_VERIFY_ALG);

	if (rv != NO_ERROR)

		return rv;

	rv = alloc_hash(&crypto->integrity_tfm, new_net_conf->integrity_alg,

	rv = alloc_ahash(&crypto->integrity_tfm, new_net_conf->integrity_alg,

			 ERR_INTEGRITY_ALG);

	if (rv != NO_ERROR)

		return rv;
@@ -2203,7 +2218,7 @@ alloc_crypto(struct crypto *crypto, struct net_conf *new_net_conf) 
		snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",

			 new_net_conf->cram_hmac_alg);



		rv = alloc_hash(&crypto->cram_hmac_tfm, hmac_name,

		rv = alloc_shash(&crypto->cram_hmac_tfm, hmac_name,

				 ERR_AUTH_ALG);

	}
@@ -2212,10 +2227,10 @@ alloc_crypto(struct crypto *crypto, struct net_conf *new_net_conf) 


static void free_crypto(struct crypto *crypto)

{

	crypto_free_hash(crypto->cram_hmac_tfm);

	crypto_free_hash(crypto->integrity_tfm);

	crypto_free_hash(crypto->csums_tfm);

	crypto_free_hash(crypto->verify_tfm);

	crypto_free_shash(crypto->cram_hmac_tfm);

	crypto_free_ahash(crypto->integrity_tfm);

	crypto_free_ahash(crypto->csums_tfm);

	crypto_free_ahash(crypto->verify_tfm);

}



int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
@@ -2292,23 +2307,23 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info) 
	rcu_assign_pointer(connection->net_conf, new_net_conf);



	if (!rsr) {

		crypto_free_hash(connection->csums_tfm);

		crypto_free_ahash(connection->csums_tfm);

		connection->csums_tfm = crypto.csums_tfm;

		crypto.csums_tfm = NULL;

	}

	if (!ovr) {

		crypto_free_hash(connection->verify_tfm);

		crypto_free_ahash(connection->verify_tfm);

		connection->verify_tfm = crypto.verify_tfm;

		crypto.verify_tfm = NULL;

	}



	crypto_free_hash(connection->integrity_tfm);

	crypto_free_ahash(connection->integrity_tfm);

	connection->integrity_tfm = crypto.integrity_tfm;

	if (connection->cstate >= C_WF_REPORT_PARAMS && connection->agreed_pro_version >= 100)

		/* Do this without trying to take connection->data.mutex again.  */

		__drbd_send_protocol(connection, P_PROTOCOL_UPDATE);



	crypto_free_hash(connection->cram_hmac_tfm);

	crypto_free_shash(connection->cram_hmac_tfm);

	connection->cram_hmac_tfm = crypto.cram_hmac_tfm;



	mutex_unlock(&connection->resource->conf_update);

drivers/block/drbd/drbd_receiver.c

+26 −30
Original line number Diff line number Diff line
@@ -1627,7 +1627,7 @@ read_in_block(struct drbd_peer_device *peer_device, u64 id, sector_t sector, 


	digest_size = 0;

	if (!trim && peer_device->connection->peer_integrity_tfm) {

		digest_size = crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm);

		digest_size = crypto_ahash_digestsize(peer_device->connection->peer_integrity_tfm);

		/*

		 * FIXME: Receive the incoming digest into the receive buffer

		 *	  here, together with its struct p_data?
@@ -1741,7 +1741,7 @@ static int recv_dless_read(struct drbd_peer_device *peer_device, struct drbd_req 


	digest_size = 0;

	if (peer_device->connection->peer_integrity_tfm) {

		digest_size = crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm);

		digest_size = crypto_ahash_digestsize(peer_device->connection->peer_integrity_tfm);

		err = drbd_recv_all_warn(peer_device->connection, dig_in, digest_size);

		if (err)

			return err;
@@ -3321,7 +3321,7 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in 
	int p_proto, p_discard_my_data, p_two_primaries, cf;

	struct net_conf *nc, *old_net_conf, *new_net_conf = NULL;

	char integrity_alg[SHARED_SECRET_MAX] = "";

	struct crypto_hash *peer_integrity_tfm = NULL;

	struct crypto_ahash *peer_integrity_tfm = NULL;

	void *int_dig_in = NULL, *int_dig_vv = NULL;



	p_proto		= be32_to_cpu(p->protocol);
@@ -3402,14 +3402,14 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in 
		 * change.

		 */



		peer_integrity_tfm = crypto_alloc_hash(integrity_alg, 0, CRYPTO_ALG_ASYNC);

		peer_integrity_tfm = crypto_alloc_ahash(integrity_alg, 0, CRYPTO_ALG_ASYNC);

		if (!peer_integrity_tfm) {

			drbd_err(connection, "peer data-integrity-alg %s not supported\n",

				 integrity_alg);

			goto disconnect;

		}



		hash_size = crypto_hash_digestsize(peer_integrity_tfm);

		hash_size = crypto_ahash_digestsize(peer_integrity_tfm);

		int_dig_in = kmalloc(hash_size, GFP_KERNEL);

		int_dig_vv = kmalloc(hash_size, GFP_KERNEL);

		if (!(int_dig_in && int_dig_vv)) {
@@ -3439,7 +3439,7 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in 
	mutex_unlock(&connection->resource->conf_update);

	mutex_unlock(&connection->data.mutex);



	crypto_free_hash(connection->peer_integrity_tfm);

	crypto_free_ahash(connection->peer_integrity_tfm);

	kfree(connection->int_dig_in);

	kfree(connection->int_dig_vv);

	connection->peer_integrity_tfm = peer_integrity_tfm;
@@ -3457,7 +3457,7 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in 
disconnect_rcu_unlock:

	rcu_read_unlock();

disconnect:

	crypto_free_hash(peer_integrity_tfm);

	crypto_free_ahash(peer_integrity_tfm);

	kfree(int_dig_in);

	kfree(int_dig_vv);

	conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
@@ -3469,15 +3469,15 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in 
 * return: NULL (alg name was "")

 *         ERR_PTR(error) if something goes wrong

 *         or the crypto hash ptr, if it worked out ok. */

static struct crypto_hash *drbd_crypto_alloc_digest_safe(const struct drbd_device *device,

static struct crypto_ahash *drbd_crypto_alloc_digest_safe(const struct drbd_device *device,

		const char *alg, const char *name)

{

	struct crypto_hash *tfm;

	struct crypto_ahash *tfm;



	if (!alg[0])

		return NULL;



	tfm = crypto_alloc_hash(alg, 0, CRYPTO_ALG_ASYNC);

	tfm = crypto_alloc_ahash(alg, 0, CRYPTO_ALG_ASYNC);

	if (IS_ERR(tfm)) {

		drbd_err(device, "Can not allocate \"%s\" as %s (reason: %ld)\n",

			alg, name, PTR_ERR(tfm));
@@ -3530,8 +3530,8 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i 
	struct drbd_device *device;

	struct p_rs_param_95 *p;

	unsigned int header_size, data_size, exp_max_sz;

	struct crypto_hash *verify_tfm = NULL;

	struct crypto_hash *csums_tfm = NULL;

	struct crypto_ahash *verify_tfm = NULL;

	struct crypto_ahash *csums_tfm = NULL;

	struct net_conf *old_net_conf, *new_net_conf = NULL;

	struct disk_conf *old_disk_conf = NULL, *new_disk_conf = NULL;

	const int apv = connection->agreed_pro_version;
@@ -3678,14 +3678,14 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i 
			if (verify_tfm) {

				strcpy(new_net_conf->verify_alg, p->verify_alg);

				new_net_conf->verify_alg_len = strlen(p->verify_alg) + 1;

				crypto_free_hash(peer_device->connection->verify_tfm);

				crypto_free_ahash(peer_device->connection->verify_tfm);

				peer_device->connection->verify_tfm = verify_tfm;

				drbd_info(device, "using verify-alg: \"%s\"\n", p->verify_alg);

			}

			if (csums_tfm) {

				strcpy(new_net_conf->csums_alg, p->csums_alg);

				new_net_conf->csums_alg_len = strlen(p->csums_alg) + 1;

				crypto_free_hash(peer_device->connection->csums_tfm);

				crypto_free_ahash(peer_device->connection->csums_tfm);

				peer_device->connection->csums_tfm = csums_tfm;

				drbd_info(device, "using csums-alg: \"%s\"\n", p->csums_alg);

			}
@@ -3729,9 +3729,9 @@ static int receive_SyncParam(struct drbd_connection *connection, struct packet_i 
	mutex_unlock(&connection->resource->conf_update);

	/* just for completeness: actually not needed,

	 * as this is not reached if csums_tfm was ok. */

	crypto_free_hash(csums_tfm);

	crypto_free_ahash(csums_tfm);

	/* but free the verify_tfm again, if csums_tfm did not work out */

	crypto_free_hash(verify_tfm);

	crypto_free_ahash(verify_tfm);

	conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);

	return -EIO;

}
@@ -4925,14 +4925,13 @@ static int drbd_do_auth(struct drbd_connection *connection) 
{

	struct drbd_socket *sock;

	char my_challenge[CHALLENGE_LEN];  /* 64 Bytes... */

	struct scatterlist sg;

	char *response = NULL;

	char *right_response = NULL;

	char *peers_ch = NULL;

	unsigned int key_len;

	char secret[SHARED_SECRET_MAX]; /* 64 byte */

	unsigned int resp_size;

	struct hash_desc desc;

	SHASH_DESC_ON_STACK(desc, connection->cram_hmac_tfm);

	struct packet_info pi;

	struct net_conf *nc;

	int err, rv;
@@ -4945,12 +4944,12 @@ static int drbd_do_auth(struct drbd_connection *connection) 
	memcpy(secret, nc->shared_secret, key_len);

	rcu_read_unlock();



	desc.tfm = connection->cram_hmac_tfm;

	desc.flags = 0;

	desc->tfm = connection->cram_hmac_tfm;

	desc->flags = 0;



	rv = crypto_hash_setkey(connection->cram_hmac_tfm, (u8 *)secret, key_len);

	rv = crypto_shash_setkey(connection->cram_hmac_tfm, (u8 *)secret, key_len);

	if (rv) {

		drbd_err(connection, "crypto_hash_setkey() failed with %d\n", rv);

		drbd_err(connection, "crypto_shash_setkey() failed with %d\n", rv);

		rv = -1;

		goto fail;

	}
@@ -5011,7 +5010,7 @@ static int drbd_do_auth(struct drbd_connection *connection) 
		goto fail;

	}



	resp_size = crypto_hash_digestsize(connection->cram_hmac_tfm);

	resp_size = crypto_shash_digestsize(connection->cram_hmac_tfm);

	response = kmalloc(resp_size, GFP_NOIO);

	if (response == NULL) {

		drbd_err(connection, "kmalloc of response failed\n");
@@ -5019,10 +5018,7 @@ static int drbd_do_auth(struct drbd_connection *connection) 
		goto fail;

	}



	sg_init_table(&sg, 1);

	sg_set_buf(&sg, peers_ch, pi.size);



	rv = crypto_hash_digest(&desc, &sg, sg.length, response);

	rv = crypto_shash_digest(desc, peers_ch, pi.size, response);

	if (rv) {

		drbd_err(connection, "crypto_hash_digest() failed with %d\n", rv);

		rv = -1;
@@ -5070,9 +5066,8 @@ static int drbd_do_auth(struct drbd_connection *connection) 
		goto fail;

	}



	sg_set_buf(&sg, my_challenge, CHALLENGE_LEN);



	rv = crypto_hash_digest(&desc, &sg, sg.length, right_response);

	rv = crypto_shash_digest(desc, my_challenge, CHALLENGE_LEN,

				 right_response);

	if (rv) {

		drbd_err(connection, "crypto_hash_digest() failed with %d\n", rv);

		rv = -1;
@@ -5091,6 +5086,7 @@ static int drbd_do_auth(struct drbd_connection *connection) 
	kfree(peers_ch);

	kfree(response);

	kfree(right_response);

	shash_desc_zero(desc);



	return rv;

}

drivers/block/drbd/drbd_worker.c

+24 −19
Original line number Diff line number Diff line
@@ -274,51 +274,56 @@ void drbd_request_endio(struct bio *bio) 
		complete_master_bio(device, &m);

}



void drbd_csum_ee(struct crypto_hash *tfm, struct drbd_peer_request *peer_req, void *digest)

void drbd_csum_ee(struct crypto_ahash *tfm, struct drbd_peer_request *peer_req, void *digest)

{

	struct hash_desc desc;

	AHASH_REQUEST_ON_STACK(req, tfm);

	struct scatterlist sg;

	struct page *page = peer_req->pages;

	struct page *tmp;

	unsigned len;



	desc.tfm = tfm;

	desc.flags = 0;

	ahash_request_set_tfm(req, tfm);

	ahash_request_set_callback(req, 0, NULL, NULL);



	sg_init_table(&sg, 1);

	crypto_hash_init(&desc);

	crypto_ahash_init(req);



	while ((tmp = page_chain_next(page))) {

		/* all but the last page will be fully used */

		sg_set_page(&sg, page, PAGE_SIZE, 0);

		crypto_hash_update(&desc, &sg, sg.length);

		ahash_request_set_crypt(req, &sg, NULL, sg.length);

		crypto_ahash_update(req);

		page = tmp;

	}

	/* and now the last, possibly only partially used page */

	len = peer_req->i.size & (PAGE_SIZE - 1);

	sg_set_page(&sg, page, len ?: PAGE_SIZE, 0);

	crypto_hash_update(&desc, &sg, sg.length);

	crypto_hash_final(&desc, digest);

	ahash_request_set_crypt(req, &sg, digest, sg.length);

	crypto_ahash_finup(req);

	ahash_request_zero(req);

}



void drbd_csum_bio(struct crypto_hash *tfm, struct bio *bio, void *digest)

void drbd_csum_bio(struct crypto_ahash *tfm, struct bio *bio, void *digest)

{

	struct hash_desc desc;

	AHASH_REQUEST_ON_STACK(req, tfm);

	struct scatterlist sg;

	struct bio_vec bvec;

	struct bvec_iter iter;



	desc.tfm = tfm;

	desc.flags = 0;

	ahash_request_set_tfm(req, tfm);

	ahash_request_set_callback(req, 0, NULL, NULL);



	sg_init_table(&sg, 1);

	crypto_hash_init(&desc);

	crypto_ahash_init(req);



	bio_for_each_segment(bvec, bio, iter) {

		sg_set_page(&sg, bvec.bv_page, bvec.bv_len, bvec.bv_offset);

		crypto_hash_update(&desc, &sg, sg.length);

		ahash_request_set_crypt(req, &sg, NULL, sg.length);

		crypto_ahash_update(req);

	}

	crypto_hash_final(&desc, digest);

	ahash_request_set_crypt(req, NULL, digest, 0);

	crypto_ahash_final(req);

	ahash_request_zero(req);

}



/* MAYBE merge common code with w_e_end_ov_req */
@@ -337,7 +342,7 @@ static int w_e_send_csum(struct drbd_work *w, int cancel) 
	if (unlikely((peer_req->flags & EE_WAS_ERROR) != 0))

		goto out;



	digest_size = crypto_hash_digestsize(peer_device->connection->csums_tfm);

	digest_size = crypto_ahash_digestsize(peer_device->connection->csums_tfm);

	digest = kmalloc(digest_size, GFP_NOIO);

	if (digest) {

		sector_t sector = peer_req->i.sector;
@@ -1113,7 +1118,7 @@ int w_e_end_csum_rs_req(struct drbd_work *w, int cancel) 
		 * a real fix would be much more involved,

		 * introducing more locking mechanisms */

		if (peer_device->connection->csums_tfm) {

			digest_size = crypto_hash_digestsize(peer_device->connection->csums_tfm);

			digest_size = crypto_ahash_digestsize(peer_device->connection->csums_tfm);

			D_ASSERT(device, digest_size == di->digest_size);

			digest = kmalloc(digest_size, GFP_NOIO);

		}
@@ -1163,7 +1168,7 @@ int w_e_end_ov_req(struct drbd_work *w, int cancel) 
	if (unlikely(cancel))

		goto out;



	digest_size = crypto_hash_digestsize(peer_device->connection->verify_tfm);

	digest_size = crypto_ahash_digestsize(peer_device->connection->verify_tfm);

	digest = kmalloc(digest_size, GFP_NOIO);

	if (!digest) {

		err = 1;	/* terminate the connection in case the allocation failed */
@@ -1235,7 +1240,7 @@ int w_e_end_ov_reply(struct drbd_work *w, int cancel) 
	di = peer_req->digest;



	if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {

		digest_size = crypto_hash_digestsize(peer_device->connection->verify_tfm);

		digest_size = crypto_ahash_digestsize(peer_device->connection->verify_tfm);

		digest = kmalloc(digest_size, GFP_NOIO);

		if (digest) {

			drbd_csum_ee(peer_device->connection->verify_tfm, peer_req, digest);