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>

1 files changed, 0 insertions, 968 deletions

diff --git a/drivers/staging/dst/dcore.c b/drivers/staging/dst/dcore.c
deleted file mode 100644
index c83ca7e3d048..000000000000
--- 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;
-		}
-		buf += sprintf(buf, "\n");
-
-		return buf - buf_orig;
-	}
-	return 0;
-}
-
-static struct device_attribute dst_node_attrs[] = {
-	__ATTR(size, 0444, dst_show_size, NULL),
-	__ATTR(type, 0444, dst_show_type, NULL),
-	__ATTR(local, 0444, dst_show_local, NULL),
-};
-
-static int dst_create_node_attributes(struct dst_node *n)
-{
-	int err, i;
-
-	for (i = 0; i < ARRAY_SIZE(dst_node_attrs); ++i) {
-		err = device_create_file(&n->info->device,
-				&dst_node_attrs[i]);
-		if (err)
-			goto err_out_remove_all;
-	}
-	return 0;
-
-err_out_remove_all:
-	while (--i >= 0)
-		device_remove_file(&n->info->device,
-				&dst_node_attrs[i]);
-
-	return err;
-}
-
-static void dst_remove_node_attributes(struct dst_node *n)
-{
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(dst_node_attrs); ++i)
-		device_remove_file(&n->info->device,
-				&dst_node_attrs[i]);
-}
-
-/*
- * Sysfs cleanup and initialization.
- * Shows number of useful parameters.
- */
-static void dst_node_sysfs_exit(struct dst_node *n)
-{
-	if (n->info) {
-		dst_remove_node_attributes(n);
-		device_unregister(&n->info->device);
-		n->info = NULL;
-	}
-}
-
-static int dst_node_sysfs_init(struct dst_node *n)
-{
-	int err;
-
-	n->info = kzalloc(sizeof(struct dst_info), GFP_KERNEL);
-	if (!n->info)
-		return -ENOMEM;
-
-	memcpy(&n->info->device, &dst_node_dev, sizeof(struct device));
-	n->info->size = n->size;
-
-	dev_set_name(&n->info->device, "dst-%s", n->name);
-	err = device_register(&n->info->device);
-	if (err) {
-		dprintk(KERN_ERR "Failed to register node '%s', err: %d.\n",
-				n->name, err);
-		goto err_out_exit;
-	}
-
-	dst_create_node_attributes(n);
-
-	return 0;
-
-err_out_exit:
-	kfree(n->info);
-	n->info = NULL;
-	return err;
-}
-
-/*
- * DST node hash tables machinery.
- */
-static inline unsigned int dst_hash(char *str, unsigned int size)
-{
-	return jhash(str, size, 0) % dst_hashtable_size;
-}
-
-static void dst_node_remove(struct dst_node *n)
-{
-	mutex_lock(&dst_hash_lock);
-	list_del_init(&n->node_entry);
-	mutex_unlock(&dst_hash_lock);
-}
-
-static void dst_node_add(struct dst_node *n)
-{
-	unsigned hash = dst_hash(n->name, sizeof(n->name));
-
-	mutex_lock(&dst_hash_lock);
-	list_add_tail(&n->node_entry, &dst_hashtable[hash]);
-	mutex_unlock(&dst_hash_lock);
-}
-
-/*
- * Cleaning node when it is about to be freed.
- * There are still users of the socket though,
- * so connection cleanup should be protected.
- */
-static void dst_node_cleanup(struct dst_node *n)
-{
-	struct dst_state *st = n->state;
-
-	if (!st)
-		return;
-
-	if (n->queue) {
-		blk_cleanup_queue(n->queue);
-
-		mutex_lock(&dst_hash_lock);
-		idr_remove(&dst_index_idr, n->disk->first_minor);
-		mutex_unlock(&dst_hash_lock);
-
-		put_disk(n->disk);
-	}
-
-	if (n->bdev) {
-		sync_blockdev(n->bdev);
-		close_bdev_exclusive(n->bdev, FMODE_READ|FMODE_WRITE);
-	}
-
-	dst_state_lock(st);
-	st->need_exit = 1;
-	dst_state_exit_connected(st);
-	dst_state_unlock(st);
-
-	wake_up(&st->thread_wait);
-
-	dst_state_put(st);
-	n->state = NULL;
-}
-
-/*
- * Free security attributes attached to given node.
- */
-static void dst_security_exit(struct dst_node *n)
-{
-	struct dst_secure *s, *tmp;
-
-	list_for_each_entry_safe(s, tmp, &n->security_list, sec_entry) {
-		list_del(&s->sec_entry);
-		kfree(s);
-	}
-}
-
-/*
- * Free node when there are no more users.
- * Actually node has to be freed on behalf od userspace process,
- * since there are number of threads, which are embedded in the
- * node, so they can not exit and free node from there, that is
- * why there is a wakeup if reference counter is not equal to zero.
- */
-void dst_node_put(struct dst_node *n)
-{
-	if (unlikely(!n))
-		return;
-
-	dprintk("%s: n: %p, refcnt: %d.\n",
-			__func__, n, atomic_read(&n->refcnt));
-
-	if (atomic_dec_and_test(&n->refcnt)) {
-		dst_node_remove(n);
-		n->trans_scan_timeout = 0;
-		dst_node_cleanup(n);
-		thread_pool_destroy(n->pool);
-		dst_node_sysfs_exit(n);
-		dst_node_crypto_exit(n);
-		dst_security_exit(n);
-		dst_node_trans_exit(n);
-
-		kfree(n);
-
-		dprintk("%s: freed n: %p.\n", __func__, n);
-	} else {
-		wake_up(&n->wait);
-	}
-}
-
-/*
- * Setting up export device: lookup by the name, get its size
- * and setup listening socket, which will accept clients, which
- * will submit IO for given storage.
- */
-static int dst_setup_export(struct dst_node *n, struct dst_ctl *ctl,
-		struct dst_export_ctl *le)
-{
-	int err;
-
-	snprintf(n->info->local, sizeof(n->info->local), "%s", le->device);
-
-	n->bdev = open_bdev_exclusive(le->device, FMODE_READ|FMODE_WRITE, NULL);
-	if (IS_ERR(n->bdev))
-		return PTR_ERR(n->bdev);
-
-	if (n->size != 0)
-		n->size = min_t(loff_t, n->bdev->bd_inode->i_size, n->size);
-	else
-		n->size = n->bdev->bd_inode->i_size;
-
-	n->info->size = n->size;
-	err = dst_node_init_listened(n, le);
-	if (err)
-		goto err_out_cleanup;
-
-	return 0;
-
-err_out_cleanup:
-	close_bdev_exclusive(n->bdev, FMODE_READ|FMODE_WRITE);
-	n->bdev = NULL;
-
-	return err;
-}
-
-/* Empty thread pool callbacks for the network processing threads. */
-static inline void *dst_thread_network_init(void *data)
-{
-	dprintk("%s: data: %p.\n", __func__, data);
-	return data;
-}
-
-static inline void dst_thread_network_cleanup(void *data)
-{
-	dprintk("%s: data: %p.\n", __func__, data);
-}
-
-/*
- * Allocate DST node and initialize some of its parameters.
- */
-static struct dst_node *dst_alloc_node(struct dst_ctl *ctl,
-		int (*start)(struct dst_node *),
-		int num)
-{
-	struct dst_node *n;
-	int err;
-
-	n = kzalloc(sizeof(struct dst_node), GFP_KERNEL);
-	if (!n)
-		return NULL;
-
-	INIT_LIST_HEAD(&n->node_entry);
-
-	INIT_LIST_HEAD(&n->security_list);
-	mutex_init(&n->security_lock);
-
-	init_waitqueue_head(&n->wait);
-
-	n->trans_scan_timeout = msecs_to_jiffies(ctl->trans_scan_timeout);
-	if (!n->trans_scan_timeout)
-		n->trans_scan_timeout = HZ;
-
-	n->trans_max_retries = ctl->trans_max_retries;
-	if (!n->trans_max_retries)
-		n->trans_max_retries = 10;
-
-	/*
-	 * Pretty much arbitrary default numbers.
-	 * 32 matches maximum number of pages in bio originated from ext3 (31).
-	 */
-	n->max_pages = ctl->max_pages;
-	if (!n->max_pages)
-		n->max_pages = 32;
-
-	if (n->max_pages > 1024)
-		n->max_pages = 1024;
-
-	n->start = start;
-	n->size = ctl->size;
-
-	atomic_set(&n->refcnt, 1);
-	atomic_long_set(&n->gen, 0);
-	snprintf(n->name, sizeof(n->name), "%s", ctl->name);
-
-	err = dst_node_sysfs_init(n);
-	if (err)
-		goto err_out_free;
-
-	n->pool = thread_pool_create(num, n->name, dst_thread_network_init,
-			dst_thread_network_cleanup, n);
-	if (IS_ERR(n->pool)) {
-		err = PTR_ERR(n->pool);
-		goto err_out_sysfs_exit;
-	}
-
-	dprintk("%s: n: %p, name: %s.\n", __func__, n, n->name);
-
-	return n;
-
-err_out_sysfs_exit:
-	dst_node_sysfs_exit(n);
-err_out_free:
-	kfree(n);
-	return NULL;
-}
-
-/*
- * Starting a node, connected to the remote server:
- * register block device and initialize transaction mechanism.
- * In revers order though.
- *
- * It will autonegotiate some parameters with the remote node
- * and update local if needed.
- *
- * Transaction initialization should be the last thing before
- * starting the node, since transaction should include not only
- * block IO, but also crypto related data (if any), which are
- * initialized separately.
- */
-static int dst_start_remote(struct dst_node *n)
-{
-	int err;
-
-	err = dst_node_trans_init(n, sizeof(struct dst_trans));
-	if (err)
-		return err;
-
-	err = dst_node_create_disk(n);
-	if (err)
-		return err;
-
-	dst_node_set_size(n);
-	add_disk(n->disk);
-
-	dprintk("DST: started remote node '%s', minor: %d.\n",
-			n->name, n->disk->first_minor);
-
-	return 0;
-}
-
-/*
- * Adding remote node and initialize connection.
- */
-static int dst_add_remote(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	int err;
-	struct dst_network_ctl *rctl = data;
-
-	if (n)
-		return -EEXIST;
-
-	if (size != sizeof(struct dst_network_ctl))
-		return -EINVAL;
-
-	n = dst_alloc_node(ctl, dst_start_remote, 1);
-	if (!n)
-		return -ENOMEM;
-
-	memcpy(&n->info->net, rctl, sizeof(struct dst_network_ctl));
-	err = dst_node_init_connected(n, rctl);
-	if (err)
-		goto err_out_free;
-
-	dst_node_add(n);
-
-	return 0;
-
-err_out_free:
-	dst_node_put(n);
-	return err;
-}
-
-/*
- * Adding export node: initializing block device and listening socket.
- */
-static int dst_add_export(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	int err;
-	struct dst_export_ctl *le = data;
-
-	if (n)
-		return -EEXIST;
-
-	if (size != sizeof(struct dst_export_ctl))
-		return -EINVAL;
-
-	n = dst_alloc_node(ctl, dst_start_export, 2);
-	if (!n)
-		return -EINVAL;
-
-	err = dst_setup_export(n, ctl, le);
-	if (err)
-		goto err_out_free;
-
-	dst_node_add(n);
-
-	return 0;
-
-err_out_free:
-	dst_node_put(n);
-	return err;
-}
-
-static int dst_node_remove_unload(struct dst_node *n)
-{
-	printk(KERN_INFO "STOPPED name: '%s', size: %llu.\n",
-			n->name, n->size);
-
-	if (n->disk)
-		del_gendisk(n->disk);
-
-	dst_node_remove(n);
-	dst_node_sysfs_exit(n);
-
-	/*
-	 * This is not a hack. Really.
-	 * Node's reference counter allows to implement fine grained
-	 * node freeing, but since all transactions (which hold node's
-	 * reference counter) are processed in the dedicated thread,
-	 * it is possible that reference will hit zero in that thread,
-	 * so we will not be able to exit thread and cleanup the node.
-	 *
-	 * So, we remove disk, so no new activity is possible, and
-	 * wait until all pending transaction are completed (either
-	 * in receiving thread or by timeout in workqueue), in this
-	 * case reference counter will be less or equal to 2 (once set in
-	 * dst_alloc_node() and then in connector message parser;
-	 * or when we force module unloading, and connector message
-	 * parser does not hold a reference, in this case reference
-	 * counter will be equal to 1),
-	 * and subsequent dst_node_put() calls will free the node.
-	 */
-	dprintk("%s: going to sleep with %d refcnt.\n",
-			__func__, atomic_read(&n->refcnt));
-	wait_event(n->wait, atomic_read(&n->refcnt) <= 2);
-
-	dst_node_put(n);
-	return 0;
-}
-
-/*
- * Remove node from the hash table.
- */
-static int dst_del_node(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	if (!n)
-		return -ENODEV;
-
-	return dst_node_remove_unload(n);
-}
-
-/*
- * Initialize crypto processing for given node.
- */
-static int dst_crypto_init(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	struct dst_crypto_ctl *crypto = data;
-
-	if (!n)
-		return -ENODEV;
-
-	if (size != sizeof(struct dst_crypto_ctl) + crypto->hash_keysize +
-			crypto->cipher_keysize)
-		return -EINVAL;
-
-	if (n->trans_cache)
-		return -EEXIST;
-
-	return dst_node_crypto_init(n, crypto);
-}
-
-/*
- * Security attributes for given node.
- */
-static int dst_security_init(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	struct dst_secure *s;
-
-	if (!n)
-		return -ENODEV;
-
-	if (size != sizeof(struct dst_secure_user))
-		return -EINVAL;
-
-	s = kmalloc(sizeof(struct dst_secure), GFP_KERNEL);
-	if (!s)
-		return -ENOMEM;
-
-	memcpy(&s->sec, data, size);
-
-	mutex_lock(&n->security_lock);
-	list_add_tail(&s->sec_entry, &n->security_list);
-	mutex_unlock(&n->security_lock);
-
-	return 0;
-}
-
-/*
- * Kill'em all!
- */
-static int dst_start_node(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size)
-{
-	int err;
-
-	if (!n)
-		return -ENODEV;
-
-	if (n->trans_cache)
-		return 0;
-
-	err = n->start(n);
-	if (err)
-		return err;
-
-	printk(KERN_INFO "STARTED name: '%s', size: %llu.\n", n->name, n->size);
-	return 0;
-}
-
-typedef int (*dst_command_func)(struct dst_node *n, struct dst_ctl *ctl,
-		void *data, unsigned int size);
-
-/*
- * List of userspace commands.
- */
-static dst_command_func dst_commands[] = {
-	[DST_ADD_REMOTE] = &dst_add_remote,
-	[DST_ADD_EXPORT] = &dst_add_export,
-	[DST_DEL_NODE] = &dst_del_node,
-	[DST_CRYPTO] = &dst_crypto_init,
-	[DST_SECURITY] = &dst_security_init,
-	[DST_START] = &dst_start_node,
-};
-
-/*
- * Configuration parser.
- */
-static void cn_dst_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
-{
-	struct dst_ctl *ctl;
-	int err;
-	struct dst_ctl_ack ack;
-	struct dst_node *n = NULL, *tmp;
-	unsigned int hash;
-
-	if (!cap_raised(nsp->eff_cap, CAP_SYS_ADMIN)) {
-		err = -EPERM;
-		goto out;
-	}
-
-	if (msg->len < sizeof(struct dst_ctl)) {
-		err = -EBADMSG;
-		goto out;
-	}
-
-	ctl = (struct dst_ctl *)msg->data;
-
-	if (ctl->cmd >= DST_CMD_MAX) {
-		err = -EINVAL;
-		goto out;
-	}
-	hash = dst_hash(ctl->name, sizeof(ctl->name));
-
-	mutex_lock(&dst_hash_lock);
-	list_for_each_entry(tmp, &dst_hashtable[hash], node_entry) {
-		if (!memcmp(tmp->name, ctl->name, sizeof(tmp->name))) {
-			n = tmp;
-			dst_node_get(n);
-			break;
-		}
-	}
-	mutex_unlock(&dst_hash_lock);
-
-	err = dst_commands[ctl->cmd](n, ctl, msg->data + sizeof(struct dst_ctl),
-			msg->len - sizeof(struct dst_ctl));
-
-	dst_node_put(n);
-out:
-	memcpy(&ack.msg, msg, sizeof(struct cn_msg));
-
-	ack.msg.ack = msg->ack + 1;
-	ack.msg.len = sizeof(struct dst_ctl_ack) - sizeof(struct cn_msg);
-
-	ack.error = err;
-
-	cn_netlink_send(&ack.msg, 0, GFP_KERNEL);
-}
-
-/*
- * Global initialization: sysfs, hash table, block device registration,
- * connector and various caches.
- */
-static int __init dst_sysfs_init(void)
-{
-	return bus_register(&dst_dev_bus_type);
-}
-
-static void dst_sysfs_exit(void)
-{
-	bus_unregister(&dst_dev_bus_type);
-}
-
-static int __init dst_hashtable_init(void)
-{
-	unsigned int i;
-
-	dst_hashtable = kcalloc(dst_hashtable_size, sizeof(struct list_head),
-			GFP_KERNEL);
-	if (!dst_hashtable)
-		return -ENOMEM;
-
-	for (i = 0; i < dst_hashtable_size; ++i)
-		INIT_LIST_HEAD(&dst_hashtable[i]);
-
-	return 0;
-}
-
-static void dst_hashtable_exit(void)
-{
-	unsigned int i;
-	struct dst_node *n, *tmp;
-
-	for (i = 0; i < dst_hashtable_size; ++i) {
-		list_for_each_entry_safe(n, tmp, &dst_hashtable[i], node_entry) {
-			dst_node_remove_unload(n);
-		}
-	}
-
-	kfree(dst_hashtable);
-}
-
-static int __init dst_sys_init(void)
-{
-	int err = -ENOMEM;
-
-	err = dst_hashtable_init();
-	if (err)
-		goto err_out_exit;
-
-	err = dst_export_init();
-	if (err)
-		goto err_out_hashtable_exit;
-
-	err = register_blkdev(dst_major, DST_NAME);
-	if (err < 0)
-		goto err_out_export_exit;
-	if (err)
-		dst_major = err;
-
-	err = dst_sysfs_init();
-	if (err)
-		goto err_out_unregister;
-
-	err = cn_add_callback(&cn_dst_id, "DST", cn_dst_callback);
-	if (err)
-		goto err_out_sysfs_exit;
-
-	printk(KERN_INFO "Distributed storage, '%s' release.\n", dst_name);
-
-	return 0;
-
-err_out_sysfs_exit:
-	dst_sysfs_exit();
-err_out_unregister:
-	unregister_blkdev(dst_major, DST_NAME);
-err_out_export_exit:
-	dst_export_exit();
-err_out_hashtable_exit:
-	dst_hashtable_exit();
-err_out_exit:
-	return err;
-}
-
-static void __exit dst_sys_exit(void)
-{
-	cn_del_callback(&cn_dst_id);
-	unregister_blkdev(dst_major, DST_NAME);
-	dst_hashtable_exit();
-	dst_sysfs_exit();
-	dst_export_exit();
-}
-
-module_init(dst_sys_init);
-module_exit(dst_sys_exit);
-
-MODULE_DESCRIPTION("Distributed storage");
-MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
-MODULE_LICENSE("GPL");