Staging: dst: remove from the tree

DST is dead, no one is using it and upstream
has abandoned it, so remove it from the tree because
it is not going anywhere.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

10 files changed, 0 insertions, 3963 deletions

diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index db0de940949..94eb86319ff 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -87,8 +87,6 @@ source "drivers/staging/frontier/Kconfig"
 
 source "drivers/staging/dream/Kconfig"
 
-source "drivers/staging/dst/Kconfig"
-
 source "drivers/staging/pohmelfs/Kconfig"
 
 source "drivers/staging/b3dfg/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index 73c6a71155e..b5e67b889f6 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -26,7 +26,6 @@ obj-$(CONFIG_RTL8192E)		+= rtl8192e/
 obj-$(CONFIG_INPUT_MIMIO)	+= mimio/
 obj-$(CONFIG_TRANZPORT)		+= frontier/
 obj-$(CONFIG_DREAM)		+= dream/
-obj-$(CONFIG_DST)		+= dst/
 obj-$(CONFIG_POHMELFS)		+= pohmelfs/
 obj-$(CONFIG_B3DFG)		+= b3dfg/
 obj-$(CONFIG_IDE_PHISON)	+= phison/
diff --git a/drivers/staging/dst/Kconfig b/drivers/staging/dst/Kconfig
deleted file mode 100644
index 448d342ac2a..00000000000
--- a/drivers/staging/dst/Kconfig
+++ /dev/null
@@ -1,67 +0,0 @@
-config DST
-	tristate "Distributed storage"
-	depends on NET && CRYPTO && SYSFS && BLK_DEV
-	select CONNECTOR
-	---help---
-	DST is a network block device storage, which can be used to organize
-	exported storage on the remote nodes into the local block device.
-
-	DST works on top of any network media and protocol; it is just a matter
-	of configuration utility to understand the correct addresses. The most
-	common example is TCP over IP, which allows to pass through firewalls and
-	create remote backup storage in a different datacenter. DST requires
-	single port to be enabled on the exporting node and outgoing connections
-	on the local node.
-
-	DST works with in-kernel client and server, which improves performance by
-	eliminating unneded data copies and by not depending on the version
-	of the external IO components. It requires userspace configuration utility
-	though.
-
-	DST uses transaction model, when each store has to be explicitly acked
-	from the remote node to be considered as successfully written. There
-	may be lots of in-flight transactions. When remote host does not ack
-	the transaction it will be resent predefined number of times with specified
-	timeouts between them. All those parameters are configurable. Transactions
-	are marked as failed after all resends complete unsuccessfully; having
-	long enough resend timeout and/or large number of resends allows not to
-	return error to the higher (FS usually) layer in case of short network
-	problems or remote node outages. In case of network RAID setup this means
-	that storage will not degrade until transactions are marked as failed, and
-	thus will not force checksum recalculation and data rebuild. In case of
-	connection failure DST will try to reconnect to the remote node automatically.
-	DST sends ping commands at idle time to detect if remote node is alive.
-
-	Because of transactional model it is possible to use zero-copy sending
-	without worry of data corruption (which in turn could be detected by the
-	strong checksums though).
-
-	DST may fully encrypt the data channel in case of untrusted channel and implement
-	strong checksum of the transferred data. It is possible to configure algorithms
-	and crypto keys; they should match on both sides of the network channel.
-	Crypto processing does not introduce noticeble performance overhead, since DST
-	uses configurable pool of threads to perform crypto processing.
-
-	DST utilizes memory pool model of all its transaction allocations (it is the
-	only additional allocation on the client) and server allocations (bio pools,
-	while pages are allocated from the slab).
-
-	At startup DST performs a simple negotiation with the export node to determine
-	access permissions and size of the exported storage. It can be extended if
-	new parameters should be autonegotiated.
-
-	DST carries block IO flags in the protocol, which allows to transparently implement
-	barriers and sync/flush operations. Those flags are used in the export node where
-	IO against the local storage is performed, which means that sync write will be sync
-	on the remote node too, which in turn improves data integrity and improved resistance
-	to errors and data corruption during power outages or storage damages.
-
-	Homepage: http://www.ioremap.net/projects/dst
-	Userspace configuration utility and the latest releases: http://www.ioremap.net/archive/dst/
-
-config DST_DEBUG
-	bool "DST debug"
-	depends on DST
-	---help---
-	This option will enable HEAVY debugging of the DST.
-	Turn it on ONLY if you have to debug some really obscure problem.
diff --git a/drivers/staging/dst/Makefile b/drivers/staging/dst/Makefile
deleted file mode 100644
index 3a8b0cf9643..00000000000
--- a/drivers/staging/dst/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-obj-$(CONFIG_DST) += nst.o
-
-nst-y := dcore.o state.o export.o thread_pool.o crypto.o trans.o
diff --git a/drivers/staging/dst/crypto.c b/drivers/staging/dst/crypto.c
deleted file mode 100644
index 351295c97a4..00000000000
--- a/drivers/staging/dst/crypto.c
+++ /dev/null
@@ -1,733 +0,0 @@
-/*
- * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
- * All rights reserved.
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/bio.h>
-#include <linux/crypto.h>
-#include <linux/dst.h>
-#include <linux/kernel.h>
-#include <linux/scatterlist.h>
-#include <linux/slab.h>
-
-/*
- * Tricky bastard, but IV can be more complex with time...
- */
-static inline u64 dst_gen_iv(struct dst_trans *t)
-{
-	return t->gen;
-}
-
-/*
- * Crypto machinery: hash/cipher support for the given crypto controls.
- */
-static struct crypto_hash *dst_init_hash(struct dst_crypto_ctl *ctl, u8 *key)
-{
-	int err;
-	struct crypto_hash *hash;
-
-	hash = crypto_alloc_hash(ctl->hash_algo, 0, CRYPTO_ALG_ASYNC);
-	if (IS_ERR(hash)) {
-		err = PTR_ERR(hash);
-		dprintk("%s: failed to allocate hash '%s', err: %d.\n",
-				__func__, ctl->hash_algo, err);
-		goto err_out_exit;
-	}
-
-	ctl->crypto_attached_size = crypto_hash_digestsize(hash);
-
-	if (!ctl->hash_keysize)
-		return hash;
-
-	err = crypto_hash_setkey(hash, key, ctl->hash_keysize);
-	if (err) {
-		dprintk("%s: failed to set key for hash '%s', err: %d.\n",
-				__func__, ctl->hash_algo, err);
-		goto err_out_free;
-	}
-
-	return hash;
-
-err_out_free:
-	crypto_free_hash(hash);
-err_out_exit:
-	return ERR_PTR(err);
-}
-
-static struct crypto_ablkcipher *dst_init_cipher(struct dst_crypto_ctl *ctl,
-		u8 *key)
-{
-	int err = -EINVAL;
-	struct crypto_ablkcipher *cipher;
-
-	if (!ctl->cipher_keysize)
-		goto err_out_exit;
-
-	cipher = crypto_alloc_ablkcipher(ctl->cipher_algo, 0, 0);
-	if (IS_ERR(cipher)) {
-		err = PTR_ERR(cipher);
-		dprintk("%s: failed to allocate cipher '%s', err: %d.\n",
-				__func__, ctl->cipher_algo, err);
-		goto err_out_exit;
-	}
-
-	crypto_ablkcipher_clear_flags(cipher, ~0);
-
-	err = crypto_ablkcipher_setkey(cipher, key, ctl->cipher_keysize);
-	if (err) {
-		dprintk("%s: failed to set key for cipher '%s', err: %d.\n",
-				__func__, ctl->cipher_algo, err);
-		goto err_out_free;
-	}
-
-	return cipher;
-
-err_out_free:
-	crypto_free_ablkcipher(cipher);
-err_out_exit:
-	return ERR_PTR(err);
-}
-
-/*
- * Crypto engine has a pool of pages to encrypt data into before sending
- * it over the network. This pool is freed/allocated here.
- */
-static void dst_crypto_pages_free(struct dst_crypto_engine *e)
-{
-	unsigned int i;
-
-	for (i = 0; i < e->page_num; ++i)
-		__free_page(e->pages[i]);
-	kfree(e->pages);
-}
-
-static int dst_crypto_pages_alloc(struct dst_crypto_engine *e, int num)
-{
-	int i;
-
-	e->pages = kmalloc(num * sizeof(struct page **), GFP_KERNEL);
-	if (!e->pages)
-		return -ENOMEM;
-
-	for (i = 0; i < num; ++i) {
-		e->pages[i] = alloc_page(GFP_KERNEL);
-		if (!e->pages[i])
-			goto err_out_free_pages;
-	}
-
-	e->page_num = num;
-	return 0;
-
-err_out_free_pages:
-	while (--i >= 0)
-		__free_page(e->pages[i]);
-
-	kfree(e->pages);
-	return -ENOMEM;
-}
-
-/*
- * Initialize crypto engine for given node.
- * Setup cipher/hash, keys, pool of threads and private data.
- */
-static int dst_crypto_engine_init(struct dst_crypto_engine *e,
-		struct dst_node *n)
-{
-	int err;
-	struct dst_crypto_ctl *ctl = &n->crypto;
-
-	err = dst_crypto_pages_alloc(e, n->max_pages);
-	if (err)
-		goto err_out_exit;
-
-	e->size = PAGE_SIZE;
-	e->data = kmalloc(e->size, GFP_KERNEL);
-	if (!e->data) {
-		err = -ENOMEM;
-		goto err_out_free_pages;
-	}
-
-	if (ctl->hash_algo[0]) {
-		e->hash = dst_init_hash(ctl, n->hash_key);
-		if (IS_ERR(e->hash)) {
-			err = PTR_ERR(e->hash);
-			e->hash = NULL;
-			goto err_out_free;
-		}
-	}
-
-	if (ctl->cipher_algo[0]) {
-		e->cipher = dst_init_cipher(ctl, n->cipher_key);
-		if (IS_ERR(e->cipher)) {
-			err = PTR_ERR(e->cipher);
-			e->cipher = NULL;
-			goto err_out_free_hash;
-		}
-	}
-
-	return 0;
-
-err_out_free_hash:
-	crypto_free_hash(e->hash);
-err_out_free:
-	kfree(e->data);
-err_out_free_pages:
-	dst_crypto_pages_free(e);
-err_out_exit:
-	return err;
-}
-
-static void dst_crypto_engine_exit(struct dst_crypto_engine *e)
-{
-	if (e->hash)
-		crypto_free_hash(e->hash);
-	if (e->cipher)
-		crypto_free_ablkcipher(e->cipher);
-	dst_crypto_pages_free(e);
-	kfree(e->data);
-}
-
-/*
- * Waiting for cipher processing to be completed.
- */
-struct dst_crypto_completion {
-	struct completion		complete;
-	int				error;
-};
-
-static void dst_crypto_complete(struct crypto_async_request *req, int err)
-{
-	struct dst_crypto_completion *c = req->data;
-
-	if (err == -EINPROGRESS)
-		return;
-
-	dprintk("%s: req: %p, err: %d.\n", __func__, req, err);
-	c->error = err;
-	complete(&c->complete);
-}
-
-static int dst_crypto_process(struct ablkcipher_request *req,
-		struct scatterlist *sg_dst, struct scatterlist *sg_src,
-		void *iv, int enc, unsigned long timeout)
-{
-	struct dst_crypto_completion c;
-	int err;
-
-	init_completion(&c.complete);
-	c.error = -EINPROGRESS;
-
-	ablkcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
-					dst_crypto_complete, &c);
-
-	ablkcipher_request_set_crypt(req, sg_src, sg_dst, sg_src->length, iv);
-
-	if (enc)
-		err = crypto_ablkcipher_encrypt(req);
-	else
-		err = crypto_ablkcipher_decrypt(req);
-
-	switch (err) {
-	case -EINPROGRESS:
-	case -EBUSY:
-		err = wait_for_completion_interruptible_timeout(&c.complete,
-				timeout);
-		if (!err)
-			err = -ETIMEDOUT;
-		else
-			err = c.error;
-		break;
-	default:
-		break;
-	}
-
-	return err;
-}
-
-/*
- * DST uses generic iteration approach for data crypto processing.
- * Single block IO request is switched into array of scatterlists,
- * which are submitted to the crypto processing iterator.
- *
- * Input and output iterator initialization are different, since
- * in output case we can not encrypt data in-place and need a
- * temporary storage, which is then being sent to the remote peer.
- */
-static int dst_trans_iter_out(struct bio *bio, struct dst_crypto_engine *e,
-		int (*iterator) (struct dst_crypto_engine *e,
-				  struct scatterlist *dst,
-				  struct scatterlist *src))
-{
-	struct bio_vec *bv;
-	int err, i;
-
-	sg_init_table(e->src, bio->bi_vcnt);
-	sg_init_table(e->dst, bio->bi_vcnt);
-
-	bio_for_each_segment(bv, bio, i) {
-		sg_set_page(&e->src[i], bv->bv_page, bv->bv_len, bv->bv_offset);
-		sg_set_page(&e->dst[i], e->pages[i], bv->bv_len, bv->bv_offset);
-
-		err = iterator(e, &e->dst[i], &e->src[i]);
-		if (err)
-			return err;
-	}
-
-	return 0;
-}
-
-static int dst_trans_iter_in(struct bio *bio, struct dst_crypto_engine *e,
-		int (*iterator) (struct dst_crypto_engine *e,
-				  struct scatterlist *dst,
-				  struct scatterlist *src))
-{
-	struct bio_vec *bv;
-	int err, i;
-
-	sg_init_table(e->src, bio->bi_vcnt);
-	sg_init_table(e->dst, bio->bi_vcnt);
-
-	bio_for_each_segment(bv, bio, i) {
-		sg_set_page(&e->src[i], bv->bv_page, bv->bv_len, bv->bv_offset);
-		sg_set_page(&e->dst[i], bv->bv_page, bv->bv_len, bv->bv_offset);
-
-		err = iterator(e, &e->dst[i], &e->src[i]);
-		if (err)
-			return err;
-	}
-
-	return 0;
-}
-
-static int dst_crypt_iterator(struct dst_crypto_engine *e,
-		struct scatterlist *sg_dst, struct scatterlist *sg_src)
-{
-	struct ablkcipher_request *req = e->data;
-	u8 iv[32];
-
-	memset(iv, 0, sizeof(iv));
-
-	memcpy(iv, &e->iv, sizeof(e->iv));
-
-	return dst_crypto_process(req, sg_dst, sg_src, iv, e->enc, e->timeout);
-}
-
-static int dst_crypt(struct dst_crypto_engine *e, struct bio *bio)
-{
-	struct ablkcipher_request *req = e->data;
-
-	memset(req, 0, sizeof(struct ablkcipher_request));
-	ablkcipher_request_set_tfm(req, e->cipher);
-
-	if (e->enc)
-		return dst_trans_iter_out(bio, e, dst_crypt_iterator);
-	else
-		return dst_trans_iter_in(bio, e, dst_crypt_iterator);
-}
-
-static int dst_hash_iterator(struct dst_crypto_engine *e,
-		struct scatterlist *sg_dst, struct scatterlist *sg_src)
-{
-	return crypto_hash_update(e->data, sg_src, sg_src->length);
-}
-
-static int dst_hash(struct dst_crypto_engine *e, struct bio *bio, void *dst)
-{
-	struct hash_desc *desc = e->data;
-	int err;
-
-	desc->tfm = e->hash;
-	desc->flags = 0;
-
-	err = crypto_hash_init(desc);
-	if (err)
-		return err;
-
-	err = dst_trans_iter_in(bio, e, dst_hash_iterator);
-	if (err)
-		return err;
-
-	err = crypto_hash_final(desc, dst);
-	if (err)
-		return err;
-
-	return 0;
-}
-
-/*
- * Initialize/cleanup a crypto thread. The only thing it should
- * do is to allocate a pool of pages as temporary storage.
- * And to setup cipher and/or hash.
- */
-static void *dst_crypto_thread_init(void *data)
-{
-	struct dst_node *n = data;
-	struct dst_crypto_engine *e;
-	int err = -ENOMEM;
-
-	e = kzalloc(sizeof(struct dst_crypto_engine), GFP_KERNEL);
-	if (!e)
-		goto err_out_exit;
-	e->src = kcalloc(2 * n->max_pages, sizeof(struct scatterlist),
-			GFP_KERNEL);
-	if (!e->src)
-		goto err_out_free;
-
-	e->dst = e->src + n->max_pages;
-
-	err = dst_crypto_engine_init(e, n);
-	if (err)
-		goto err_out_free_all;
-
-	return e;
-
-err_out_free_all:
-	kfree(e->src);
-err_out_free:
-	kfree(e);
-err_out_exit:
-	return ERR_PTR(err);
-}
-
-static void dst_crypto_thread_cleanup(void *private)
-{
-	struct dst_crypto_engine *e = private;
-
-	dst_crypto_engine_exit(e);
-	kfree(e->src);
-	kfree(e);
-}
-
-/*
- * Initialize crypto engine for given node: store keys, create pool
- * of threads, initialize each one.
- *
- * Each thread has unique ID, but 0 and 1 are reserved for receiving and
- * accepting threads (if export node), so IDs could start from 2, but starting
- * them from 10 allows easily understand what this thread is for.
- */
-int dst_node_crypto_init(struct dst_node *n, struct dst_crypto_ctl *ctl)
-{
-	void *key = (ctl + 1);
-	int err = -ENOMEM, i;
-	char name[32];
-
-	if (ctl->hash_keysize) {
-		n->hash_key = kmalloc(ctl->hash_keysize, GFP_KERNEL);
-		if (!n->hash_key)
-			goto err_out_exit;
-		memcpy(n->hash_key, key, ctl->hash_keysize);
-	}
-
-	if (ctl->cipher_keysize) {
-		n->cipher_key = kmalloc(ctl->cipher_keysize, GFP_KERNEL);
-		if (!n->cipher_key)
-			goto err_out_free_hash;
-		memcpy(n->cipher_key, key, ctl->cipher_keysize);
-	}
-	memcpy(&n->crypto, ctl, sizeof(struct dst_crypto_ctl));
-
-	for (i = 0; i < ctl->thread_num; ++i) {
-		snprintf(name, sizeof(name), "%s-crypto-%d", n->name, i);
-		/* Unique ids... */
-		err = thread_pool_add_worker(n->pool, name, i + 10,
-			dst_crypto_thread_init, dst_crypto_thread_cleanup, n);
-		if (err)
-			goto err_out_free_threads;
-	}
-
-	return 0;
-
-err_out_free_threads:
-	while (--i >= 0)
-		thread_pool_del_worker_id(n->pool, i+10);
-
-	if (ctl->cipher_keysize)
-		kfree(n->cipher_key);
-	ctl->cipher_keysize = 0;
-err_out_free_hash:
-	if (ctl->hash_keysize)
-		kfree(n->hash_key);
-	ctl->hash_keysize = 0;
-err_out_exit:
-	return err;
-}
-
-void dst_node_crypto_exit(struct dst_node *n)
-{
-	struct dst_crypto_ctl *ctl = &n->crypto;
-
-	if (ctl->cipher_algo[0] || ctl->hash_algo[0]) {
-		kfree(n->hash_key);
-		kfree(n->cipher_key);
-	}
-}
-
-/*
- * Thrad pool setup callback. Just stores a transaction in private data.
- */
-static int dst_trans_crypto_setup(void *crypto_engine, void *trans)
-{
-	struct dst_crypto_engine *e = crypto_engine;
-
-	e->private = trans;
-	return 0;
-}
-
-#if 0
-static void dst_dump_bio(struct bio *bio)
-{
-	u8 *p;
-	struct bio_vec *bv;
-	int i;
-
-	bio_for_each_segment(bv, bio, i) {
-		dprintk("%s: %llu/%u: size: %u, offset: %u, data: ",
-				__func__, bio->bi_sector, bio->bi_size,
-				bv->bv_len, bv->bv_offset);
-
-		p = kmap(bv->bv_page) + bv->bv_offset;
-		for (i = 0; i < bv->bv_len; ++i)
-			printk(KERN_DEBUG "%02x ", p[i]);
-		kunmap(bv->bv_page);
-		printk("\n");
-	}
-}
-#endif
-
-/*
- * Encrypt/hash data and send it to the network.
- */
-static int dst_crypto_process_sending(struct dst_crypto_engine *e,
-		struct bio *bio, u8 *hash)
-{
-	int err;
-
-	if (e->cipher) {
-		err = dst_crypt(e, bio);
-		if (err)
-			goto err_out_exit;
-	}
-
-	if (e->hash) {
-		err = dst_hash(e, bio, hash);
-		if (err)
-			goto err_out_exit;
-
-#ifdef CONFIG_DST_DEBUG
-		{
-			unsigned int i;
-
-			/* dst_dump_bio(bio); */
-
-			printk(KERN_DEBUG "%s: bio: %llu/%u, rw: %lu, hash: ",
-				__func__, (u64)bio->bi_sector,
-				bio->bi_size, bio_data_dir(bio));
-			for (i = 0; i < crypto_hash_digestsize(e->hash); ++i)
-					printk("%02x ", hash[i]);
-			printk("\n");
-		}
-#endif
-	}
-
-	return 0;
-
-err_out_exit:
-	return err;
-}
-
-/*
- * Check if received data is valid. Decipher if it is.
- */
-static int dst_crypto_process_receiving(struct dst_crypto_engine *e,
-		struct bio *bio, u8 *hash, u8 *recv_hash)
-{
-	int err;
-
-	if (e->hash) {
-		int mismatch;
-
-		err = dst_hash(e, bio, hash);
-		if (err)
-			goto err_out_exit;
-
-		mismatch = !!memcmp(recv_hash, hash,
-				crypto_hash_digestsize(e->hash));
-#ifdef CONFIG_DST_DEBUG
-		/* dst_dump_bio(bio); */
-
-		printk(KERN_DEBUG "%s: bio: %llu/%u, rw: %lu, hash mismatch: %d",
-			__func__, (u64)bio->bi_sector, bio->bi_size,
-			bio_data_dir(bio), mismatch);
-		if (mismatch) {
-			unsigned int i;
-
-			printk(", recv/calc: ");
-			for (i = 0; i < crypto_hash_digestsize(e->hash); ++i)
-				printk("%02x/%02x ", recv_hash[i], hash[i]);
-
-		}
-		printk("\n");
-#endif
-		err = -1;
-		if (mismatch)
-			goto err_out_exit;
-	}
-
-	if (e->cipher) {
-		err = dst_crypt(e, bio);
-		if (err)
-			goto err_out_exit;
-	}
-
-	return 0;
-
-err_out_exit:
-	return err;
-}
-
-/*
- * Thread pool callback to encrypt data and send it to the netowork.
- */
-static int dst_trans_crypto_action(void *crypto_engine, void *schedule_data)
-{
-	struct dst_crypto_engine *e = crypto_engine;
-	struct dst_trans *t = schedule_data;
-	struct bio *bio = t->bio;
-	int err;
-
-	dprintk("%s: t: %p, gen: %llu, cipher: %p, hash: %p.\n",
-			__func__, t, t->gen, e->cipher, e->hash);
-
-	e->enc = t->enc;
-	e->iv = dst_gen_iv(t);
-
-	if (bio_data_dir(bio) == WRITE) {
-		err = dst_crypto_process_sending(e, bio, t->cmd.hash);
-		if (err)
-			goto err_out_exit;
-
-		if (e->hash) {
-			t->cmd.csize = crypto_hash_digestsize(e->hash);
-			t->cmd.size += t->cmd.csize;
-		}
-
-		return dst_trans_send(t);
-	} else {
-		u8 *hash = e->data + e->size/2;
-
-		err = dst_crypto_process_receiving(e, bio, hash, t->cmd.hash);
-		if (err)
-			goto err_out_exit;
-
-		dst_trans_remove(t);
-		dst_trans_put(t);
-	}
-
-	return 0;
-
-err_out_exit:
-	t->error = err;
-	dst_trans_put(t);
-	return err;
-}
-
-/*
- * Schedule crypto processing for given transaction.
- */
-int dst_trans_crypto(struct dst_trans *t)
-{
-	struct dst_node *n = t->n;
-	int err;
-
-	err = thread_pool_schedule(n->pool,
-		dst_trans_crypto_setup, dst_trans_crypto_action,
-		t, MAX_SCHEDULE_TIMEOUT);
-	if (err)
-		goto err_out_exit;
-
-	return 0;
-
-err_out_exit:
-	dst_trans_put(t);
-	return err;
-}
-
-/*
- * Crypto machinery for the export node.
- */
-static int dst_export_crypto_setup(void *crypto_engine, void *bio)
-{
-	struct dst_crypto_engine *e = crypto_engine;
-
-	e->private = bio;
-	return 0;
-}
-
-static int dst_export_crypto_action(void *crypto_engine, void *schedule_data)
-{
-	struct dst_crypto_engine *e = crypto_engine;
-	struct bio *bio = schedule_data;
-	struct dst_export_priv *p = bio->bi_private;
-	int err;
-
-	dprintk("%s: e: %p, data: %p, bio: %llu/%u, dir: %lu.\n",
-			__func__, e, e->data, (u64)bio->bi_sector,
-			bio->bi_size, bio_data_dir(bio));
-
-	e->enc = (bio_data_dir(bio) == READ);
-	e->iv = p->cmd.id;
-
-	if (bio_data_dir(bio) == WRITE) {
-		u8 *hash = e->data + e->size/2;
-
-		err = dst_crypto_process_receiving(e, bio, hash, p->cmd.hash);
-		if (err)
-			goto err_out_exit;
-
-		generic_make_request(bio);
-	} else {
-		err = dst_crypto_process_sending(e, bio, p->cmd.hash);
-		if (err)
-			goto err_out_exit;
-
-		if (e->hash) {
-			p->cmd.csize = crypto_hash_digestsize(e->hash);
-			p->cmd.size += p->cmd.csize;
-		}
-
-		err = dst_export_send_bio(bio);
-	}
-	return 0;
-
-err_out_exit:
-	bio_put(bio);
-	return err;
-}
-
-int dst_export_crypto(struct dst_node *n, struct bio *bio)
-{
-	int err;
-
-	err = thread_pool_schedule(n->pool,
-		dst_export_crypto_setup, dst_export_crypto_action,
-		bio, MAX_SCHEDULE_TIMEOUT);
-	if (err)
-		goto err_out_exit;
-
-	return 0;
-
-err_out_exit:
-	bio_put(bio);
-	return err;
-}
diff --git a/drivers/staging/dst/dcore.c b/drivers/staging/dst/dcore.c
deleted file mode 100644
index c83ca7e3d04..00000000000
--- a/drivers/staging/dst/dcore.c
+++ /dev/null
@@ -1,968 +0,0 @@
-/*
- * 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
- * All rights reserved.
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/blkdev.h>
-#include <linux/bio.h>
-#include <linux/buffer_head.h>
-#include <linux/connector.h>
-#include <linux/dst.h>
-#include <linux/device.h>
-#include <linux/jhash.h>
-#include <linux/idr.h>
-#include <linux/init.h>
-#include <linux/namei.h>
-#include <linux/slab.h>
-#include <linux/socket.h>
-
-#include <linux/in.h>
-#include <linux/in6.h>
-
-#include <net/sock.h>
-
-static int dst_major;
-
-static DEFINE_MUTEX(dst_hash_lock);
-static struct list_head *dst_hashtable;
-static unsigned int dst_hashtable_size = 128;
-module_param(dst_hashtable_size, uint, 0644);
-
-static char dst_name[] = "Dementianting goldfish";
-
-static DEFINE_IDR(dst_index_idr);
-static struct cb_id cn_dst_id = { CN_DST_IDX, CN_DST_VAL };
-
-/*
- * DST sysfs tree for device called 'storage':
- *
- * /sys/bus/dst/devices/storage/
- * /sys/bus/dst/devices/storage/type : 192.168.4.80:1025
- * /sys/bus/dst/devices/storage/size : 800
- * /sys/bus/dst/devices/storage/name : storage
- */
-
-static int dst_dev_match(struct device *dev, struct device_driver *drv)
-{
-	return 1;
-}
-
-static struct bus_type dst_dev_bus_type = {
-	.name 		= "dst",
-	.match 		= &dst_dev_match,
-};
-
-static void dst_node_release(struct device *dev)
-{
-	struct dst_info *info = container_of(dev, struct dst_info, device);
-
-	kfree(info);
-}
-
-static struct device dst_node_dev = {
-	.bus 		= &dst_dev_bus_type,
-	.release 	= &dst_node_release
-};
-
-/*
- * Setting size of the node after it was changed.
- */
-static void dst_node_set_size(struct dst_node *n)
-{
-	struct block_device *bdev;
-
-	set_capacity(n->disk, n->size >> 9);
-
-	bdev = bdget_disk(n->disk, 0);
-	if (bdev) {
-		mutex_lock(&bdev->bd_inode->i_mutex);
-		i_size_write(bdev->bd_inode, n->size);
-		mutex_unlock(&bdev->bd_inode->i_mutex);
-		bdput(bdev);
-	}
-}
-
-/*
- * Distributed storage request processing function.
- */
-static int dst_request(struct request_queue *q, struct bio *bio)
-{
-	struct dst_node *n = q->queuedata;
-	int err = -EIO;
-
-	if (bio_empty_barrier(bio) && !blk_queue_discard(q)) {
-		/*
-		 * This is a dirty^Wnice hack, but if we complete this
-		 * operation with -EOPNOTSUPP like intended, XFS
-		 * will stuck and freeze the machine. This may be
-		 * not particulary XFS problem though, but it is the
-		 * only FS which sends empty barrier at umount time
-		 * I worked with.
-		 *
-		 * Empty barriers are not allowed anyway, see 51fd77bd9f512
-		 * for example, although later it was changed to
-		 * bio_rw_flagged(bio, BIO_RW_DISCARD) only, which does not
-		 * work in this case.
-		 */
-		/* err = -EOPNOTSUPP; */
-		err = 0;
-		goto end_io;
-	}
-
-	bio_get(bio);
-
-	return dst_process_bio(n, bio);
-
-end_io:
-	bio_endio(bio, err);
-	return err;
-}
-
-/*
- * Open/close callbacks for appropriate block device.
- */
-static int dst_bdev_open(struct block_device *bdev, fmode_t mode)
-{
-	struct dst_node *n = bdev->bd_disk->private_data;
-
-	dst_node_get(n);
-	return 0;
-}
-
-static int dst_bdev_release(struct gendisk *disk, fmode_t mode)
-{
-	struct dst_node *n = disk->private_data;
-
-	dst_node_put(n);
-	return 0;
-}
-
-static struct block_device_operations dst_blk_ops = {
-	.open		= dst_bdev_open,
-	.release	= dst_bdev_release,
-	.owner		= THIS_MODULE,
-};
-
-/*
- * Block layer binding - disk is created when array is fully configured
- * by userspace request.
- */
-static int dst_node_create_disk(struct dst_node *n)
-{
-	int err = -ENOMEM;
-	u32 index = 0;
-
-	n->queue = blk_init_queue(NULL, NULL);
-	if (!n->queue)
-		goto err_out_exit;
-
-	n->queue->queuedata = n;
-	blk_queue_make_request(n->queue, dst_request);
-	blk_queue_max_phys_segments(n->queue, n->max_pages);
-	blk_queue_max_hw_segments(n->queue, n->max_pages);
-
-	err = -ENOMEM;
-	n->disk = alloc_disk(1);
-	if (!n->disk)
-		goto err_out_free_queue;
-
-	if (!(n->state->permissions & DST_PERM_WRITE)) {
-		printk(KERN_INFO "DST node %s attached read-only.\n", n->name);
-		set_disk_ro(n->disk, 1);
-	}
-
-	if (!idr_pre_get(&dst_index_idr, GFP_KERNEL))
-		goto err_out_put;
-
-	mutex_lock(&dst_hash_lock);
-	err = idr_get_new(&dst_index_idr, NULL, &index);
-	mutex_unlock(&dst_hash_lock);
-	if (err)
-		goto err_out_put;
-
-	n->disk->major = dst_major;
-	n->disk->first_minor = index;
-	n->disk->fops = &dst_blk_ops;
-	n->disk->queue = n->queue;
-	n->disk->private_data = n;
-	snprintf(n->disk->disk_name, sizeof(n->disk->disk_name),
-			"dst-%s", n->name);
-
-	return 0;
-
-err_out_put:
-	put_disk(n->disk);
-err_out_free_queue:
-	blk_cleanup_queue(n->queue);
-err_out_exit:
-	return err;
-}
-
-/*
- * Sysfs machinery: show device's size.
- */
-static ssize_t dst_show_size(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct dst_info *info = container_of(dev, struct dst_info, device);
-
-	return sprintf(buf, "%llu\n", info->size);
-}
-
-/*
- * Show local exported device.
- */
-static ssize_t dst_show_local(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct dst_info *info = container_of(dev, struct dst_info, device);
-
-	return sprintf(buf, "%s\n", info->local);
-}
-
-/*
- * Shows type of the remote node - device major/minor number
- * for local nodes and address (af_inet ipv4/ipv6 only) for remote nodes.
- */
-static ssize_t dst_show_type(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct dst_info *info = container_of(dev, struct dst_info, device);
-	int family = info->net.addr.sa_family;
-
-	if (family == AF_INET) {
-		struct sockaddr_in *sin = (struct sockaddr_in *)&info->net.addr;
-		return sprintf(buf, "%u.%u.%u.%u:%d\n",
-			NIPQUAD(sin->sin_addr.s_addr), ntohs(sin->sin_port));
-	} else if (family == AF_INET6) {
-		struct sockaddr_in6 *sin = (struct sockaddr_in6 *)
-				&info->net.addr;
-		return sprintf(buf,
-			"%pi6:%d\n",
-			&sin->sin6_addr, ntohs(sin->sin6_port));
-	} else {
-		int i, sz = PAGE_SIZE - 2; /* 0 symbol and '\n' below */
-		int size, addrlen = info->net.addr.sa_data_len;
-		unsigned char *a = (unsigned char *)&info->net.addr.sa_data;
-		char *buf_orig = buf;
-
-		size = snprintf(buf, sz, "family: %d, addrlen: %u, addr: ",
-				family, addrlen);
-		sz -= size;
-		buf += size;
-
-		for (i = 0; i < addrlen; ++i) {
-			if (sz < 3)
-				break;
-
-			size = snprintf(buf, sz, "%02x ", a[i]);
-			sz -= size;
-			buf += size;