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/*
* 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"
int dnbd3_blk_add_device(dnbd3_device_t *dev, int minor)
{
struct gendisk *disk;
struct request_queue *blk_queue;
init_waitqueue_head(&dev->process_queue_send);
init_waitqueue_head(&dev->process_queue_receive);
INIT_LIST_HEAD(&dev->request_queue_send);
INIT_LIST_HEAD(&dev->request_queue_receive);
dev->vid = 0;
dev->rid = 0;
dev->sock = NULL;
dev->num_servers = 0;
dev->thread_send = NULL;
dev->thread_receive = NULL;
if (!(disk = alloc_disk(1)))
{
printk("ERROR: dnbd3 alloc_disk failed.\n");
return -EIO;
}
disk->major = major;
disk->first_minor = minor;
sprintf(disk->disk_name, "dnbd%d", minor);
set_capacity(disk, 0);
set_disk_ro(disk, 1);
disk->fops = &dnbd3_blk_ops;
spin_lock_init(&dev->blk_lock);
if ((blk_queue = blk_init_queue(&dnbd3_blk_request, &dev->blk_lock)) == NULL)
{
printk("ERROR: dnbd3 blk_init_queue failed.\n");
return -EIO;
}
blk_queue_logical_block_size(blk_queue, DNBD3_BLOCK_SIZE);
disk->queue = blk_queue;
disk->private_data = dev;
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, disk->queue);
dev->disk = disk;
add_disk(disk); // must be last
return 0;
}
int dnbd3_blk_del_device(dnbd3_device_t *dev)
{
if (dev->sock)
{
sock_release(dev->sock);
dev->sock = NULL;
}
if (&dev->hb_timer)
del_timer(&dev->hb_timer);
del_gendisk(dev->disk);
put_disk(dev->disk);
blk_cleanup_queue(dev->disk->queue);
return 0;
}
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)
{
dnbd3_device_t *dev = bdev->bd_disk->private_data;
int minor = dev->disk->first_minor;
dnbd3_ioctl_t *msg = kmalloc(sizeof(dnbd3_ioctl_t), GFP_KERNEL);
copy_from_user((char *)msg, (char *)arg, sizeof(*msg));
switch (cmd)
{
case IOCTL_OPEN:
strcpy(dev->host, msg->host);
strcpy(dev->port, msg->port);
dev->vid = msg->vid;
dev->rid = msg->rid;
dnbd3_net_connect(dev);
break;
case IOCTL_CLOSE:
dnbd3_net_disconnect(dev);
dnbd3_blk_del_device(dev);
dnbd3_blk_add_device(dev, minor);
break;
case IOCTL_SWITCH:
dnbd3_net_disconnect(dev);
strcpy(dev->host, msg->host);
dnbd3_net_connect(dev);
break;
case BLKFLSBUF:
break;
default:
kfree(msg);
return -1;
}
kfree(msg);
return 0;
}
void dnbd3_blk_request(struct request_queue *q)
{
struct request *req;
dnbd3_device_t *dev;
while ((req = blk_fetch_request(q)) != NULL)
{
dev = req->rq_disk->private_data;
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, &dev->request_queue_send);
spin_unlock_irq(q->queue_lock);
wake_up(&dev->process_queue_send);
spin_lock_irq(q->queue_lock);
}
}
}
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