First working version :)

17 files changed, 601 insertions, 706 deletions

diff --git a/src/client/client.bak b/src/client/client.bak
deleted file mode 100644
index bacfa52..0000000
--- a/src/client/client.bak
+++ /dev/null
@@ -1,75 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <netdb.h>
-#include <arpa/inet.h>
-#include <unistd.h>
-
-#include <math.h>
-
-#include "../include/types.h"
-
-#define FILE_SIZE 721127424
-
-int main(int argc, char *argv[])
-{
-	struct sockaddr_in server;
-	unsigned long addr;
-	int sock;
-
-	// Create socket
-	sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-	if (sock < 0)
-	{
-		printf("ERROR: Socket failure\n");
-		return EXIT_FAILURE;
-	}
-
-	addr = inet_addr(HOST);
-	memcpy((char *) &server.sin_addr, &addr, sizeof(addr));
-	server.sin_family = AF_INET; // IPv4
-	server.sin_port = htons(PORT); // set port number
-
-	// Connect to server
-	if (connect(sock, (struct sockaddr*) &server, sizeof(server)) < 0)
-	{
-		printf("ERROR: Connect failure\n");
-		return EXIT_FAILURE;
-	}
-
-	// Set data
-	struct dnbd3_request request;
-	struct dnbd3_reply reply;
-	request.num = 0;
-
-	// Send to server
-	int i;
-	off_t blocks = FILE_SIZE / DNBD3_BLOCK_SIZE;
-	int e = log(DNBD3_BLOCK_SIZE) / log(2); // logarithmus dualis
-
-
-	for (i = 0; i < blocks; i++)
-	{
-		request.num = i << e; // multiplie by e
-		send(sock, (char *) &request, sizeof(request), 0);
-		recv(sock, &reply, DNBD3_BLOCK_SIZE, MSG_WAITALL);
-		write(STDOUT_FILENO, reply.data, DNBD3_BLOCK_SIZE);
-	}
-
-	/* Fetch "rest" bytes */
-	int rest = FILE_SIZE % DNBD3_BLOCK_SIZE;
-	if (rest != 0)
-	{
-		request.num = i * DNBD3_BLOCK_SIZE;
-		send(sock, (char *) &request, sizeof(request), 0);
-		recv(sock, &reply, sizeof(struct dnbd3_reply), MSG_WAITALL);
-		write(STDOUT_FILENO, reply.data, rest);
-	}
-
-	close(sock);
-	return EXIT_SUCCESS;
-}
diff --git a/src/client/client.c b/src/client/client.c
index 87f20d5..68b7f5c 100644
--- a/src/client/client.c
+++ b/src/client/client.c
@@ -1,3 +1,23 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <fcntl.h>
@@ -6,7 +26,7 @@
 #include <sys/ioctl.h>
 #include <netinet/in.h>
 
-#include "../include/types.h"
+#include "../types.h"
 #include "../version.h"
 
 void print_help(char* argv_0)
diff --git a/src/config.h b/src/config.h
index ec41da2..1d31f60 100644
--- a/src/config.h
+++ b/src/config.h
@@ -1,7 +1,7 @@
 #ifndef CONFIG_H_
 #define CONFIG_H_
 
-#define PORT 5003 // TODO: make obsolete
+#define PORT 5003
 
 #define KERNEL_SECTOR_SIZE 512
 #define DNBD3_BLOCK_SIZE 4096
diff --git a/src/kernel/blk.c b/src/kernel/blk.c
new file mode 100644
index 0000000..bf7f4e8
--- /dev/null
+++ b/src/kernel/blk.c
@@ -0,0 +1,76 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "blk.h"
+#include "net.h"
+
+struct block_device_operations dnbd3_blk_ops =
+{ .owner = THIS_MODULE, .ioctl = dnbd3_blk_ioctl, };
+
+int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
+		unsigned long arg)
+{
+	switch (cmd)
+	{
+	case IOCTL_SET_HOST:
+		_host = (char *) arg;
+		break;
+
+	case IOCTL_SET_PORT:
+		_port = (char *) arg;
+		break;
+
+	case IOCTL_CONNECT:
+		dnbd3_net_connect();
+		break;
+	case BLKFLSBUF:
+		break;
+
+	default:
+		return -1;
+
+	}
+	return 0;
+}
+
+void dnbd3_blk_request(struct request_queue *q)
+{
+	struct request *req;
+
+	if (!_sock)
+		return;
+
+	while ((req = blk_fetch_request(q)) != NULL)
+	{
+		if (req->cmd_type != REQ_TYPE_FS)
+		{
+			__blk_end_request_all(req, 0);
+			continue;
+		}
+
+		if (rq_data_dir(req) == READ)
+		{
+			list_add_tail(&req->queuelist, &_request_queue_send);
+			spin_unlock_irq(q->queue_lock);
+			wake_up(&_process_queue_send);
+			spin_lock_irq(q->queue_lock);
+		}
+	}
+}
diff --git a/src/kernel/blk.h b/src/kernel/blk.h
new file mode 100644
index 0000000..d2e8162
--- /dev/null
+++ b/src/kernel/blk.h
@@ -0,0 +1,33 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef BLK_H_
+#define BLK_H_
+
+#include "dnbd3.h"
+
+extern struct block_device_operations dnbd3_blk_ops;
+
+int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
+		unsigned long arg);
+
+void dnbd3_blk_request(struct request_queue *q);
+
+#endif /* BLK_H_ */
diff --git a/src/kernel/core.c b/src/kernel/core.c
new file mode 100644
index 0000000..3b6ce54
--- /dev/null
+++ b/src/kernel/core.c
@@ -0,0 +1,94 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "dnbd3.h"
+#include "blk.h"
+
+// block
+int major;
+struct gendisk *disk;
+struct request_queue *dnbd3_queue;
+spinlock_t dnbd3_lock;
+
+// network
+char* _host;
+char* _port;
+struct socket *_sock;
+
+// process
+wait_queue_head_t _process_queue_send;
+wait_queue_head_t _process_queue_receive;
+struct list_head _request_queue_send;
+struct list_head _request_queue_receive;
+
+static int __init dnbd3_init(void)
+{
+	// initialize queues
+	init_waitqueue_head(&_process_queue_send);
+	init_waitqueue_head(&_process_queue_receive);
+	INIT_LIST_HEAD(&_request_queue_send);
+	INIT_LIST_HEAD(&_request_queue_receive);
+
+	// initialize block device
+	if ((major = register_blkdev(0, "dnbd")) == 0)
+	{
+		printk("ERROR: dnbd3 register_blkdev failed.\n");
+		return -EIO;
+	}
+	if (!(disk = alloc_disk(1)))
+	{
+		printk("ERROR: dnbd3 alloc_disk failed.\n");
+		return -EIO;
+	}
+	disk->major = major;
+	disk->first_minor = 0;
+	sprintf(disk->disk_name, "dnbd0");
+	set_capacity(disk, 0);
+	set_disk_ro(disk, 1);
+	disk->fops = &dnbd3_blk_ops;
+	spin_lock_init(&dnbd3_lock);
+	if ((dnbd3_queue = blk_init_queue(&dnbd3_blk_request, &dnbd3_lock)) == NULL)
+	{
+		printk("ERROR: dnbd3 blk_init_queue failed.\n");
+		return -EIO;
+	}
+	blk_queue_logical_block_size(dnbd3_queue, DNBD3_BLOCK_SIZE);
+	disk->queue = dnbd3_queue;
+
+	add_disk(disk); // must be last
+
+	printk("INFO: dnbd3 init successful.\n");
+	return 0;
+}
+
+static void __exit dnbd3_exit(void)
+{
+	if (_sock)
+		sock_release(_sock);
+	unregister_blkdev(major, "dnbd");
+	del_gendisk(disk);
+	put_disk(disk);
+	blk_cleanup_queue(dnbd3_queue);
+	printk("INFO: dnbd3 exit.\n");
+}
+
+module_init( dnbd3_init);
+module_exit( dnbd3_exit);
+MODULE_LICENSE("GPL");
diff --git a/src/kernel/dnbd3.h b/src/kernel/dnbd3.h
new file mode 100644
index 0000000..11eee48
--- /dev/null
+++ b/src/kernel/dnbd3.h
@@ -0,0 +1,47 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef DNBD_H_
+#define DNBD_H_
+
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <net/sock.h>
+
+#include "config.h"
+#include "types.h"
+
+// block
+extern struct gendisk *disk;
+extern spinlock_t dnbd3_lock;
+
+// network
+extern char* _host;
+extern char* _port;
+extern struct socket *_sock;
+
+// process
+extern wait_queue_head_t _process_queue_send;
+extern wait_queue_head_t _process_queue_receive;
+extern struct list_head _request_queue_send;
+extern struct list_head _request_queue_receive;
+
+#endif /* DNBD_H_ */
diff --git a/src/kernel/main.c b/src/kernel/main.c
deleted file mode 100644
index 1802b5f..0000000
--- a/src/kernel/main.c
+++ /dev/null
@@ -1,216 +0,0 @@
-#include <linux/fs.h>
-#include <linux/module.h>
-#include <linux/blkdev.h>
-#include <net/sock.h>
-
-// Own
-#include "config.h"
-#include "include/types.h"
-
-static int major;
-static struct gendisk *disk;
-static struct request_queue *dnbd3_queue;
-
-DEFINE_SPINLOCK( dnbd3_lock);
-
-static struct socket *_sock;
-static struct dnbd3_request _dnbd3_request;
-static struct dnbd3_reply _dnbd3_reply;
-
-static char* host;
-static char* port;
-
-unsigned int inet_addr(char *str)
-{
-	int a, b, c, d;
-	char arr[4];
-	sscanf(str, "%d.%d.%d.%d", &a, &b, &c, &d);
-	arr[0] = a;
-	arr[1] = b;
-	arr[2] = c;
-	arr[3] = d;
-	return *(unsigned int*) arr;
-}
-
-void connect(void)
-{
-	if (!host || !port)
-	{
-		printk("ERROR: Host or port not set.");
-		return;
-	}
-
-	// initialize socket
-	struct sockaddr_in sin;
-	if (sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &_sock) < 0)
-	{
-		printk("ERROR: dnbd3 couldn't create socket.\n");
-		return;
-	}
-	sin.sin_family = AF_INET;
-	sin.sin_addr.s_addr = inet_addr(host);
-	sin.sin_port = htons(simple_strtol(port, NULL, 10));
-	if (kernel_connect(_sock, (struct sockaddr *) &sin, sizeof(sin), 0) < 0)
-	{
-		printk("ERROR: dnbd3 couldn't connect to given host.\n");
-		return;
-	}
-
-	// prepare message
-	struct msghdr msg;
-	struct kvec iov;
-	_sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-	msg.msg_name = NULL;
-	msg.msg_namelen = 0;
-	msg.msg_control = NULL;
-	msg.msg_controllen = 0;
-	msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
-	// send request
-	_dnbd3_request.cmd = CMD_GET_SIZE;
-	iov.iov_base = &_dnbd3_request;
-	iov.iov_len = sizeof(_dnbd3_request);
-	kernel_sendmsg(_sock, &msg, &iov, 1, sizeof(_dnbd3_request));
-
-	// receive replay
-	iov.iov_base = &_dnbd3_reply;
-	iov.iov_len = sizeof(_dnbd3_reply);
-	kernel_recvmsg(_sock, &msg, &iov, 1, sizeof(_dnbd3_reply), msg.msg_flags);
-
-	// set filesize
-	printk("INFO: dnbd3 filesize: %llu\n", _dnbd3_reply.filesize);
-	set_capacity(disk, _dnbd3_reply.filesize >> 9); /* 512 Byte blocks */
-}
-
-void dnbd3_request(struct request_queue *q)
-{
-	if (!_sock)
-		return;
-
-	struct request *req;
-	struct msghdr msg;
-	struct kvec iov;
-
-	_sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-	msg.msg_name = NULL;
-	msg.msg_namelen = 0;
-	msg.msg_control = NULL;
-	msg.msg_controllen = 0;
-	msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
-	while ((req = blk_fetch_request(q)) != NULL)
-	{
-		if (req->cmd_type != REQ_TYPE_FS)
-		{
-			if (!__blk_end_request_cur(req, 0))
-				req = blk_fetch_request(q);
-			continue;
-		}
-
-		spin_unlock_irq(q->queue_lock);
-		if (rq_data_dir(req) == READ)
-		{
-			_dnbd3_request.cmd = CMD_GET_BLOCK;
-			_dnbd3_request.offset = blk_rq_pos(req) << 9; // *512
-			_dnbd3_request.size = blk_rq_bytes(req); // blk_rq_bytes() Returns bytes left to complete in the entire request
-
-			// send request
-			iov.iov_base = &_dnbd3_request;
-			iov.iov_len = sizeof(_dnbd3_request);
-			kernel_sendmsg(_sock, &msg, &iov, 1, sizeof(_dnbd3_request));
-
-			// receive replay
-			struct req_iterator iter;
-			struct bio_vec *bvec;
-			rq_for_each_segment(bvec, req, iter)
-			{
-				iov.iov_base = kmap(bvec->bv_page) + bvec->bv_offset;
-				iov.iov_len = bvec->bv_len;
-				kernel_recvmsg(_sock, &msg, &iov, 1, bvec->bv_len, msg.msg_flags);
-				kunmap(bvec->bv_page);
-			}
-		}
-
-		spin_lock_irq(q->queue_lock);
-		__blk_end_request_all(req, 0);
-	}
-}
-
-int dnbd3_ioctl(struct block_device *bdev, fmode_t mode,
-		unsigned int cmd, unsigned long arg)
-{
-	switch (cmd)
-	{
-	case IOCTL_SET_HOST:
-		host = (char *) arg;
-		break;
-
-	case IOCTL_SET_PORT:
-		port = (char *) arg;
-		break;
-
-	case IOCTL_CONNECT:
-		connect();
-		break;
-	case BLKFLSBUF:
-		// TODO: if missing, hdparm tells "BLKFLSBUF failed: Operation not permitted". Figure out what this should do.
-		break;
-
-	default:
-		return -1;
-
-	}
-	return 0;
-}
-
-struct block_device_operations dnbd3_ops =
-{ .owner = THIS_MODULE, .ioctl = dnbd3_ioctl, };
-
-static int __init dnbd3_init(void)
-{
-	// Init blkdev
-	if ((major = register_blkdev(0, "dnbd")) == 0)
-	{
-		printk("ERROR: dnbd3 register_blkdev failed.\n");
-		return -EIO;
-	}
-	if (!(disk = alloc_disk(1)))
-	{
-		printk("ERROR: dnbd3 alloc_disk failed.\n");
-		return -EIO;
-	}
-	disk->major = major;
-	disk->first_minor = 0;
-	sprintf(disk->disk_name, "dnbd0");
-	set_capacity(disk, 0);
-	//set_disk_ro(disk, 1);
-	disk->fops = &dnbd3_ops;
-
-	if ((dnbd3_queue = blk_init_queue(&dnbd3_request, &dnbd3_lock)) == NULL)
-	{
-		printk("ERROR: dnbd3 blk_init_queue failed.\n");
-		return -EIO;
-	}
-
-	blk_queue_logical_block_size(dnbd3_queue, DNBD3_BLOCK_SIZE); // set logical block size for the queue
-	disk->queue = dnbd3_queue;
-
-	add_disk(disk);
-	printk("INFO: dnbd3 init successful.\n");
-	return 0;
-}
-
-static void __exit dnbd3_exit(void)
-{
-	if (_sock)
-		sock_release(_sock);
-	unregister_blkdev(major, "dnbd");
-	del_gendisk(disk);
-	put_disk(disk);
-	blk_cleanup_queue(dnbd3_queue);
-	printk("INFO: dnbd3 exit.\n");
-}
-
-module_init( dnbd3_init);
-module_exit( dnbd3_exit);
-MODULE_LICENSE("GPL");
diff --git a/src/kernel/main.c.bak b/src/kernel/main.c.bak
deleted file mode 100644
index 600ed3c..0000000
--- a/src/kernel/main.c.bak
+++ /dev/null
@@ -1,322 +0,0 @@
-#include <linux/fs.h>
-#include <linux/module.h>
-#include <linux/blkdev.h>
-
-// Own
-#include "config.h"
-#include "include/types.h"
-
-// Network
-#include <net/sock.h>
-//#include <linux/net.h>
-//#include <net/ip.h>
-
-static int major;
-static struct gendisk *disk;
-static struct request_queue *dnbd3_queue;
-
-DEFINE_SPINLOCK( dnbd3_lock);
-
-struct socket *sock;
-struct dnbd3_request r;
-struct dnbd3_reply rp;
-
-uint64_t filesize;
-
-char* host;
-char* port;
-
-// TODO: schauen obs nicht eine fertige gibt
-static unsigned int inet_addr(char *str)
-{
-	int a, b, c, d;
-	char arr[4];
-	sscanf(str, "%d.%d.%d.%d", &a, &b, &c, &d);
-	arr[0] = a;
-	arr[1] = b;
-	arr[2] = c;
-	arr[3] = d;
-	return *(unsigned int*) arr;
-}
-
-static void connect()
-{
-	if (!host || !port)
-	{
-		printk("ERROR: Host or port not set.");
-		return;
-	}
-
-	// Init kernel-socket
-//	static unsigned char address[4] =
-//	{ 132, 230, 4, 29 };
-
-	struct sockaddr_in sin;
-
-	if (sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &sock) < 0)
-	{
-		printk("DNBD3: Couldn't create socket.\n");
-	}
-	sin.sin_family = AF_INET;
-	//memcpy(&sin.sin_addr.s_addr, address, 4);
-	sin.sin_addr.s_addr = inet_addr(host);
-	sin.sin_port = htons(simple_strtol(port, NULL, 10));
-	if (kernel_connect(sock, (struct sockaddr *) &sin, sizeof(sin), 0) < 0)
-	{
-		printk("DNBD3: Couldn't connect.\n");
-		return;
-	}
-
-	// Ask for filesize
-	struct msghdr msg;
-	struct kvec iov;
-	int size, result;
-	void *buf = &r;
-	r.cmd = CMD_GET_SIZE;
-	size = sizeof(r);
-	do
-	{
-		sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-		iov.iov_base = (char *) buf;
-		iov.iov_len = size;
-		msg.msg_name = NULL;
-		msg.msg_namelen = 0;
-		msg.msg_control = NULL;
-		msg.msg_controllen = 0;
-		msg.msg_flags = MSG_NOSIGNAL; // No SIGPIPE
-
-		result = kernel_sendmsg(sock, &msg, &iov, 1, size);
-
-		if (result <= 0)
-		{
-			if (result == 0)
-				result = -EPIPE; /* short read */
-			break;
-		}
-		size -= result;
-		buf += result;
-	} while (size > 0);
-	buf = &rp;
-	size = sizeof(rp);
-	do
-	{
-		sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-		iov.iov_base = (char *) buf;
-		iov.iov_len = size;
-		msg.msg_name = NULL;
-		msg.msg_namelen = 0;
-		msg.msg_control = NULL;
-		msg.msg_controllen = 0;
-		msg.msg_flags = MSG_NOSIGNAL; // No SIGPIPE
-
-		result = kernel_recvmsg(sock, &msg, &iov, 1, size, msg.msg_flags);
-
-		if (result <= 0)
-		{
-			if (result == 0)
-				result = -EPIPE; /* short read */
-			break;
-		}
-		size -= result;
-		buf += result;
-	} while (size > 0);
-
-	filesize = rp.num;
-	printk("Filesize: %llu\n", filesize);
-
-	//filesize = 721127424;
-	set_capacity(disk, filesize >> 9); /* 512 Byte blocks */
-
-}
-
-static void dnbd3_request(struct request_queue *q)
-{
-	if (!sock)
-		return;
-
-	struct request *req;
-	unsigned long start, to_copy;
-	int size, result;
-	void *buf;
-	struct msghdr msg;
-	struct kvec iov;
-
-	while ((req = blk_fetch_request(q)) != NULL)
-	{
-		if (req->cmd_type != REQ_TYPE_FS)
-		{
-			if (!__blk_end_request_cur(req, 0))
-				req = blk_fetch_request(q);
-			continue;
-		}
-		start = blk_rq_pos(req) << 9; // *512
-
-		//to_copy = blk_rq_cur_bytes(req);	// Returns bytes left to complete in the current segment
-		to_copy = blk_rq_bytes(req); // blk_rq_bytes() Returns bytes left to complete in the entire request
-
-		spin_unlock_irq(q->queue_lock);
-		if ((start + to_copy) <= filesize)
-		{
-			if (rq_data_dir(req) == READ)
-			{
-				// Send msg
-				//printk("Send...\n");
-				buf = &r;
-				r.cmd = CMD_GET_BLOCK;
-				r.num = start;
-				r.to_copy = to_copy;
-				size = sizeof(r);
-				do
-				{
-					sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-					iov.iov_base = (char *) buf;
-					iov.iov_len = size;
-					msg.msg_name = NULL;
-					msg.msg_namelen = 0;
-					msg.msg_control = NULL;
-					msg.msg_controllen = 0;
-					msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
-					result = kernel_sendmsg(sock, &msg, &iov, 1, size);
-
-					if (result <= 0)
-					{
-						if (result == 0)
-							result = -EPIPE; /* short read */
-						break;
-					}
-					size -= result;
-					buf += result;
-				} while (size > 0);
-
-				// Test - receive msg
-				struct req_iterator iter;
-				struct bio_vec *bvec;
-				rq_for_each_segment(bvec, req, iter)
-					{
-						void *kaddr = kmap(bvec->bv_page);
-						buf = kaddr + bvec->bv_offset;
-						size = bvec->bv_len;
-						do
-						{
-							sock->sk->sk_allocation = GFP_NOIO; // GFP_NOIO: blocking is possible, but no I/O will be performed.
-							iov.iov_base = buf;
-							iov.iov_len = size;
-							msg.msg_name = NULL;
-							msg.msg_namelen = 0;
-							msg.msg_control = NULL;
-							msg.msg_controllen = 0;
-							msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
-							result = kernel_recvmsg(sock, &msg, &iov, 1, size,
-									msg.msg_flags);
-
-							if (result <= 0)
-							{
-								if (result == 0)
-									result = -EPIPE; /* short read */
-								break;
-							}
-							size -= result;
-							buf += result;
-
-							if (size > 0)
-								printk("SIZE > 0\n");
-
-						} while (size > 0);
-
-						kunmap(bvec->bv_page);
-					}
-
-			}
-			else
-			{
-				printk("ERROR: Write not supported.");
-			}
-		}
-		else
-		{
-			printk("ERROR: %ld not in range...\n", start + to_copy);
-		}
-		spin_lock_irq(q->queue_lock);
-		__blk_end_request_all(req, 0);
-	}
-}
-
-static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode,
-		unsigned int cmd, unsigned long arg)
-{
-	switch (cmd)
-	{
-
-	case IOCTL_SET_HOST:
-		host = (char *) arg;
-		break;
-
-	case IOCTL_SET_PORT:
-		port = (char *) arg;
-		break;
-
-	case IOCTL_CONNECT:
-		connect();
-		break;
-
-	default:
-		return -1;
-
-	}
-	return 0;
-}
-
-static struct block_device_operations dnbd3_ops =
-{ .owner = THIS_MODULE, .ioctl = dnbd3_ioctl, };
-
-static int __init dnbd3_init(void)
-{
-
-	// Init blkdev
-	if ((major = register_blkdev(0, "dnbd")) == 0)
-	{
-		printk("dnbd3: can't get majornumber\n");
-		return -EIO;
-	}
-	printk("major: %d\n", major);
-	if (!(disk = alloc_disk(1)))
-	{
-		printk("alloc_disk failed ...\n");
-		goto out;
-	}
-	disk->major = major;
-	disk->first_minor = 0;
-	sprintf(disk->disk_name, "dnbd0");
-	//set_capacity(disk, filesize >> 9); /* 512 Byte blocks */
-	set_capacity(disk, 0);
-	disk->fops = &dnbd3_ops;
-
-	if ((dnbd3_queue = blk_init_queue(&dnbd3_request, &dnbd3_lock)) == NULL)
-		goto out;
-
-	blk_queue_logical_block_size(dnbd3_queue, DNBD3_BLOCK_SIZE); // set logical block size for the queue
-//	blk_queue_max_hw_sectors(dnbd3_queue, DNBD3_BLOCK_SIZE / KERNEL_SECTOR_SIZE); // set max sectors for a request for this queue, min 8
-//	blk_queue_max_segments(dnbd3_queue, 1); // set max hw segments for a request for this queue
-//	blk_queue_max_segment_size(dnbd3_queue, DNBD3_BLOCK_SIZE); // set max segment size for blk_rq_map_sg, min 4096
-	disk->queue = dnbd3_queue;
-
-	add_disk(disk);
-	return 0;
-	out: return -EIO;
-}
-
-static void __exit dnbd3_exit(void)
-{
-	if (sock)
-		sock_release(sock);
-	unregister_blkdev(major, "dnbd");
-	del_gendisk(disk);
-	put_disk(disk);
-	blk_cleanup_queue(dnbd3_queue);
-}
-
-module_init( dnbd3_init);
-module_exit( dnbd3_exit);
-MODULE_LICENSE("GPL");
diff --git a/src/kernel/net.c b/src/kernel/net.c
new file mode 100644
index 0000000..0e7a871
--- /dev/null
+++ b/src/kernel/net.c
@@ -0,0 +1,206 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "net.h"
+#include "utils.h"
+
+void dnbd3_net_connect(void)
+{
+	struct sockaddr_in sin;
+	struct msghdr msg;
+	struct kvec iov;
+	struct dnbd3_request dnbd3_request;
+	struct dnbd3_reply dnbd3_reply;
+	struct task_struct *thread_send;
+	struct task_struct *thread_receive;
+
+	if (!_host || !_port)
+	{
+		printk("ERROR: Host or port not set.");
+		return;
+	}
+
+	// initialize socket
+	if (sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &_sock) < 0)
+	{
+		printk("ERROR: dnbd3 couldn't create socket.\n");
+		return;
+	}
+	_sock->sk->sk_allocation = GFP_NOIO;
+	sin.sin_family = AF_INET;
+	sin.sin_addr.s_addr = inet_addr(_host);
+	sin.sin_port = htons(simple_strtol(_port, NULL, 10));
+	if (kernel_connect(_sock, (struct sockaddr *) &sin, sizeof(sin), 0) < 0)
+	{
+		printk("ERROR: dnbd3 couldn't connect to given host.\n");
+		return;
+	}
+
+	// prepare message and send request
+	dnbd3_request.cmd = CMD_GET_SIZE;
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
+
+	iov.iov_base = &dnbd3_request;
+	iov.iov_len = sizeof(dnbd3_request);
+	kernel_sendmsg(_sock, &msg, &iov, 1, sizeof(dnbd3_request));
+
+	// receive replay
+	iov.iov_base = &dnbd3_reply;
+	iov.iov_len = sizeof(dnbd3_reply);
+	kernel_recvmsg(_sock, &msg, &iov, 1, sizeof(dnbd3_reply), msg.msg_flags);
+
+	// set filesize
+	// FIXME: files > 4GB
+	printk("INFO: dnbd3 filesize: %llu\n", dnbd3_reply.filesize);
+	set_capacity(disk, dnbd3_reply.filesize >> 9); /* 512 Byte blocks */
+
+	// start sending thread
+	thread_send = kthread_create(dnbd3_net_send, NULL, "none");
+	wake_up_process(thread_send);
+
+	// start receiving thread
+	thread_receive = kthread_create(dnbd3_net_receive, NULL, "none");
+	wake_up_process(thread_receive);
+}
+
+int dnbd3_net_send(void *data)
+{
+	struct dnbd3_request dnbd3_request;
+	struct request *blk_request;
+	struct msghdr msg;
+	struct kvec iov;
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
+
+	set_user_nice(current, -20);
+
+	while (!kthread_should_stop() || !list_empty(&_request_queue_send))
+	{
+		wait_event_interruptible(_process_queue_send,
+				kthread_should_stop() || !list_empty(&_request_queue_send));
+
+		if (list_empty(&_request_queue_send))
+			continue;
+
+		// extract block request
+		spin_lock_irq(&dnbd3_lock);
+		blk_request = list_entry(_request_queue_send.next, struct request, queuelist);
+		list_del_init(&blk_request->queuelist);
+		spin_unlock_irq(&dnbd3_lock);
+
+		// prepare net request
+		dnbd3_request.cmd = CMD_GET_BLOCK;
+		dnbd3_request.offset = blk_rq_pos(blk_request) << 9; // *512
+		dnbd3_request.size = blk_rq_bytes(blk_request); // blk_rq_bytes() Returns bytes left to complete in the entire request
+		memcpy(dnbd3_request.handle, &blk_request, sizeof(blk_request));
+		iov.iov_base = &dnbd3_request;
+		iov.iov_len = sizeof(dnbd3_request);
+
+		// send net request
+		if (kernel_sendmsg(_sock, &msg, &iov, 1, sizeof(dnbd3_request)) <= 0)
+			printk("ERROR: kernel_sendmsg\n");
+
+		spin_lock_irq(&dnbd3_lock);
+		list_add_tail(&blk_request->queuelist, &_request_queue_receive);
+		spin_unlock_irq(&dnbd3_lock);
+		wake_up(&_process_queue_receive);
+	}
+	return 0;
+}
+
+int dnbd3_net_receive(void *data)
+{
+	struct dnbd3_reply dnbd3_reply;
+	struct request *blk_request;
+	struct msghdr msg;
+	struct kvec iov;
+	struct req_iterator iter;
+	struct bio_vec *bvec;
+	unsigned long flags;
+	sigset_t blocked, oldset;
+	struct request *tmp_request, *received_request;
+	void *kaddr;
+	int size;
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
+
+	set_user_nice(current, -20);
+
+	while (!kthread_should_stop() || !list_empty(&_request_queue_receive))
+	{
+		wait_event_interruptible(_process_queue_receive,
+				kthread_should_stop() || !list_empty(&_request_queue_receive));
+
+		// receive net replay
+		iov.iov_base = &dnbd3_reply;
+		iov.iov_len = sizeof(dnbd3_reply);
+		kernel_recvmsg(_sock, &msg, &iov, 1, sizeof(dnbd3_reply),
+				msg.msg_flags);
+
+		// search for replied request in queue
+		received_request = *(struct request **) dnbd3_reply.handle;
+		spin_lock_irq(&dnbd3_lock);
+		list_for_each_entry_safe(blk_request, tmp_request,
+				&_request_queue_receive, queuelist)
+		{
+			if (blk_request != received_request)
+				continue;
+
+			list_del_init(&blk_request->queuelist);
+			break;
+		}
+		spin_unlock_irq(&dnbd3_lock);
+
+		// receive data and answer to block layer
+		rq_for_each_segment(bvec, blk_request, iter)
+			{
+				siginitsetinv(&blocked, sigmask(SIGKILL));
+				sigprocmask(SIG_SETMASK, &blocked, &oldset);
+
+				kaddr = kmap(bvec->bv_page) + bvec->bv_offset;
+				size = bvec->bv_len;
+				iov.iov_base = kaddr;
+				iov.iov_len = size;
+				kernel_recvmsg(_sock, &msg, &iov, 1, size, msg.msg_flags);
+				kunmap(bvec->bv_page);
+
+				sigprocmask(SIG_SETMASK, &oldset, NULL);
+			}
+
+		spin_lock_irqsave(&dnbd3_lock, flags);
+		__blk_end_request_all(blk_request, 0);
+		spin_unlock_irqrestore(&dnbd3_lock, flags);
+	}
+
+	return 0;
+}
+
diff --git a/src/kernel/net.h b/src/kernel/net.h
new file mode 100644
index 0000000..22c0cbd
--- /dev/null
+++ b/src/kernel/net.h
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef NET_H_
+#define NET_H_
+
+#include "dnbd3.h"
+
+void dnbd3_net_connect(void);
+
+int dnbd3_net_send(void *data);
+
+int dnbd3_net_receive(void *data);
+
+#endif /* NET_H_ */
diff --git a/src/kernel/utils.c b/src/kernel/utils.c
new file mode 100644
index 0000000..423ceb9
--- /dev/null
+++ b/src/kernel/utils.c
@@ -0,0 +1,33 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include <linux/kernel.h>
+
+unsigned int inet_addr(char *str)
+{
+	int a, b, c, d;
+	char arr[4];
+	sscanf(str, "%d.%d.%d.%d", &a, &b, &c, &d);
+	arr[0] = a;
+	arr[1] = b;
+	arr[2] = c;
+	arr[3] = d;
+	return *(unsigned int*) arr;
+}
diff --git a/src/kernel/utils.h b/src/kernel/utils.h
new file mode 100644
index 0000000..6b7fcee
--- /dev/null
+++ b/src/kernel/utils.h
@@ -0,0 +1,26 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef UTILS_H_
+#define UTILS_H_
+
+unsigned int inet_addr(char *str);
+
+#endif /* UTILS_H_ */
diff --git a/src/server/file.c b/src/server/file.c
deleted file mode 100644
index c53ca15..0000000
--- a/src/server/file.c
+++ /dev/null
@@ -1,58 +0,0 @@
-#include <fcntl.h>
-#include <errno.h>
-#include "file.h"
-
-int file_open(char *filename)
-{
-	int fd = open(filename, O_RDONLY);
-	if (fd == -1)
-		return -1;
-
-	struct stat st;
-	if (fstat(fd, &st) == -1)
-		return -1;
-
-	return fd;
-}
-
-int file_getsize(int fd, off_t *size)
-{
-	*size = lseek64(fd, 0, SEEK_END);
-
-	if (*size == -1)
-		return -1;
-
-	return 0;
-}
-
-int file_read(int fd, void *buf, size_t size, off_t pos)
-{
-	off_t newpos = lseek(fd, pos, SEEK_SET);
-
-	if (newpos == -1)
-		return -1;
-
-	size_t nleft = size;
-	ssize_t nread;
-	char *ptr = buf;
-
-	while (nleft > 0)
-	{
-		if ((nread = read(fd, ptr, nleft)) < 0)
-		{
-			if (errno == EINTR)
-				continue;
-
-			return -1;
-		}
-		if (nread == 0)
-		{
-			break;
-		}
-
-		nleft -= nread;
-		ptr += nread;
-	}
-
-	return 0;
-}
diff --git a/src/server/file.h b/src/server/file.h
deleted file mode 100644
index e61849a..0000000
--- a/src/server/file.h
+++ /dev/null
@@ -1,7 +0,0 @@
-#include <unistd.h>
-
-int file_open(char *filename);
-
-int file_getsize(int fd, off_t *size);
-
-int file_read(int fd, void *buf, size_t size, off_t pos);
diff --git a/src/server/server.c b/src/server/server.c
index e38a0e3..dfa53d7 100644
--- a/src/server/server.c
+++ b/src/server/server.c
@@ -12,12 +12,12 @@
 #include <getopt.h>
 #include <netinet/in.h>
 #include <sys/sendfile.h>
+#include <sys/stat.h>
 
 #include <pthread.h>
 
-#include "../include/types.h"
+#include "../types.h"
 #include "../version.h"
-#include "file.h"
 
 int file;
 
@@ -40,40 +40,44 @@ void print_version()
 
 void handle_sigpipe(int signum)
 {
-	printf("Program received signal SIGPIPE, Broken pipe (errno: %i)\n", errno);
+	printf("ERROR: Received signal SIGPIPE, Broken pipe (errno: %i)\n", errno);
 	return;
 }
 
-void *echo(void *client_socket)
+void *handle_query(void *client_socket)
 {
 	int sock = (int) client_socket;
 	struct dnbd3_request request;
 	struct dnbd3_reply reply;
 	uint16_t cmd;
 	off_t filesize;
+	struct stat st;
+	fstat(file, &st);
+	filesize = st.st_size;
 
 	while (recv(sock, &request, sizeof(struct dnbd3_request), MSG_WAITALL) > 0)
 	{
 		cmd = request.cmd;
-//		char buf[request.size];
 		switch (cmd)
 		{
 		case CMD_GET_SIZE:
 			reply.cmd = request.cmd;
-			file_getsize(file, &filesize);
 			reply.filesize = filesize;
 			send(sock, (char *) &reply, sizeof(struct dnbd3_reply), 0);
 			break;
 
 		case CMD_GET_BLOCK:
-//			printf("CMD: %i, Byte: %llu, Size: %llu\n",request.cmd, request.offset, request.size);
-//			file_read(file, buf, request.size, request.offset);
-//			send(sock, (char *) buf, request.size, 0);
-			sendfile(sock, file, (off_t *) &request.offset, request.size);
+			reply.cmd = request.cmd;
+			memcpy(reply.handle, request.handle, sizeof(request.handle));
+			send(sock, (char *) &reply, sizeof(struct dnbd3_reply), 0);
+
+			if (sendfile(sock, file, (off_t *) &request.offset, request.size) <0)
+				printf("ERROR: sendfile returned -1\n");
+
 			break;
 
 		default:
-			;
+			printf("ERROR: Unknown command\n");
 		}
 
 	}
@@ -102,7 +106,7 @@ int main(int argc, char* argv[])
 		switch (opt)
 		{
 		case 'f':
-			file = file_open(optarg);
+			file = open(optarg, O_RDONLY);
 			break;
 		case 'h':
 			print_help(argv[0]);
@@ -119,11 +123,9 @@ int main(int argc, char* argv[])
 	signal(SIGPIPE, handle_sigpipe);
 
 	struct sockaddr_in server;
-	struct sockaddr_in client[50];
+	struct sockaddr_in client;
 	int sock, fd;
 	unsigned int len;
-	pthread_t thread[50];
-	int i=1;
 
 	// Create socket
 	sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
@@ -154,20 +156,21 @@ int main(int argc, char* argv[])
 
 	printf("INFO: Server is ready...\n");
 
-	// TODO: dyn threads
 	while (1)
 	{
 		len = sizeof(client);
-		fd = accept(sock, (struct sockaddr*) &client[i], &len);
+		fd = accept(sock, (struct sockaddr*) &client, &len);
 		if (fd < 0)
 		{
 			printf("ERROR: Accept failure\n");
 			exit(EXIT_FAILURE);
 		}
+		printf("INFO: Client: %s connected\n", inet_ntoa(client.sin_addr));
 
-		printf("INFO: Client: %s connected\n", inet_ntoa(client[i].sin_addr));
-		pthread_create(&(thread[i]), NULL, echo, (void *) fd);
-		pthread_detach(thread[i++]);
+		// FIXME: catch SIGKILL/SIGTERM and close all socket before exit
+		pthread_t thread;
+		pthread_create(&(thread), NULL, handle_query, (void *) fd);
+		pthread_detach(thread);
 	}
 	return EXIT_SUCCESS;
 }
diff --git a/src/include/types.h b/src/types.h
index ea34616..3005f62 100644
--- a/src/include/types.h
+++ b/src/types.h
@@ -1,22 +1,24 @@
 #ifndef TYPES_H_
 #define TYPES_H_
 
-#include "../config.h"
-
-#define DNBD_MAGIC  'd'
-
-#define CMD_GET_BLOCK   1
-#define CMD_GET_SIZE    2
+#include "config.h"
 
+// ioctl
+#define DNBD3_MAGIC  'd'
 #define IOCTL_SET_HOST	_IO(0xab, 1)
 #define IOCTL_SET_PORT	_IO(0xab, 2)
 #define IOCTL_CONNECT	_IO(0xab, 3)
 
+// network
+#define CMD_GET_BLOCK   1
+#define CMD_GET_SIZE    2
+
 #pragma pack(1)
 typedef struct dnbd3_request {
 	uint16_t cmd;
 	uint64_t offset;
 	uint64_t size;
+	char handle[8];
 } dnbd3_request_t;
 #pragma pack(0)
 
@@ -24,6 +26,7 @@ typedef struct dnbd3_request {
 typedef struct dnbd3_reply {
 	uint16_t cmd;
 	uint64_t filesize;
+	char handle[8];
 } dnbd3_reply_t;
 #pragma pack(0)