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/* SPDX-License-Identifier: GPL-2.0 */
/*
* 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/version.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/blk-mq.h>
#include <linux/mutex.h>
#include <net/sock.h>
#include <dnbd3/config.h>
#include <dnbd3/types.h>
#include <dnbd3/shared/serialize.h>
extern int major;
typedef struct {
unsigned long rtts[4]; // Last four round trip time measurements in µs
uint16_t protocol_version; // dnbd3 protocol version of this server
uint8_t failures; // How many times the server was unreachable
uint8_t best_count; // Number of times server measured best
struct sockaddr_storage host; // Address of server
} dnbd3_alt_server_t;
typedef struct {
// block
struct gendisk *disk;
struct blk_mq_tag_set tag_set;
struct request_queue *queue;
spinlock_t blk_lock;
// sysfs
struct kobject kobj;
// network
struct mutex alt_servers_lock;
char *imgname;
struct socket *sock;
struct {
unsigned long rtt;
struct sockaddr_storage host;
uint16_t protocol_version;
} cur_server;
serialized_buffer_t payload_buffer;
dnbd3_alt_server_t alt_servers[NUMBER_SERVERS]; // array of alt servers, protected by alt_servers_lock
uint8_t discover, panic, update_available, panic_count;
atomic_t connection_lock;
uint8_t use_server_provided_alts;
uint16_t rid;
uint32_t heartbeat_count;
uint64_t reported_size;
// server switch
struct socket *better_sock;
// process
struct task_struct *thread_send;
struct task_struct *thread_receive;
struct task_struct *thread_discover;
struct timer_list hb_timer;
wait_queue_head_t process_queue_send;
wait_queue_head_t process_queue_discover;
struct list_head request_queue_send;
struct list_head request_queue_receive;
} dnbd3_device_t;
extern inline struct device *dnbd3_device_to_dev(dnbd3_device_t *dev);
extern inline int is_same_server(const struct sockaddr_storage *const x, const struct sockaddr_storage *const y);
extern int dnbd3_host_to_sockaddr(const dnbd3_host_t *host, struct sockaddr_storage *dest);
extern dnbd3_alt_server_t *get_existing_alt_from_host(const dnbd3_host_t *const host, dnbd3_device_t *const dev);
extern dnbd3_alt_server_t *get_existing_alt_from_addr(const struct sockaddr_storage *const addr,
dnbd3_device_t *const dev);
extern int dnbd3_add_server(dnbd3_device_t *dev, dnbd3_host_t *host);
extern int dnbd3_rem_server(dnbd3_device_t *dev, dnbd3_host_t *host);
#endif /* DNBD_H_ */
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