/**
* Write the physical details regarding the block device to the store, and
* switch to Connected state.
*/
static void connect(struct backend_info *be)
{
xenbus_transaction_t xbt;
int err;
struct xenbus_device *dev = be->dev;
DPRINTK("%s", dev->otherend);
/* Supply the information about the device the frontend needs */
again:
err = xenbus_transaction_start(&xbt);
if (err) {
xenbus_dev_fatal(dev, err, "starting transaction");
return;
}
err = xenbus_printf(xbt, dev->nodename, "sectors", "%lu",
vbd_size(&be->blkif->vbd));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/sectors",
dev->nodename);
goto abort;
}
/* FIXME: use a typename instead */
err = xenbus_printf(xbt, dev->nodename, "info", "%u",
vbd_info(&be->blkif->vbd));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/info",
dev->nodename);
goto abort;
}
err = xenbus_printf(xbt, dev->nodename, "sector-size", "%lu",
vbd_secsize(&be->blkif->vbd));
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/sector-size",
dev->nodename);
goto abort;
}
err = xenbus_transaction_end(xbt, 0);
if (err == -EAGAIN)
goto again;
if (err)
xenbus_dev_fatal(dev, err, "ending transaction");
err = xenbus_switch_state(dev, XenbusStateConnected);
if (err)
xenbus_dev_fatal(dev, err, "switching to Connected state",
dev->nodename);
return;
abort:
xenbus_transaction_end(xbt, 1);
}
void vbd_resize(blkif_t *blkif)
{
struct vbd *vbd = &blkif->vbd;
struct xenbus_transaction xbt;
int err;
struct xenbus_device *dev = blkback_xenbus(blkif->be);
unsigned long long new_size = vbd_size(vbd);
printk(KERN_INFO "VBD Resize: new size %Lu\n", new_size);
vbd->size = new_size;
again:
err = xenbus_transaction_start(&xbt);
if (err) {
printk(KERN_WARNING "Error starting transaction");
return;
}
err = xenbus_printf(xbt, dev->nodename, "sectors", "%Lu",
vbd_size(vbd));
if (err) {
printk(KERN_WARNING "Error writing new size");
goto abort;
}
/*
* Write the current state; we will use this to synchronize
* the front-end. If the current state is "connected" the
* front-end will get the new size information online.
*/
err = xenbus_printf(xbt, dev->nodename, "state", "%d", dev->state);
if (err) {
printk(KERN_WARNING "Error writing the state");
goto abort;
}
err = xenbus_transaction_end(xbt, 0);
if (err == -EAGAIN)
goto again;
if (err)
printk(KERN_WARNING "Error ending transaction");
abort:
xenbus_transaction_end(xbt, 1);
}
int vbd_create(blkif_t *blkif, blkif_vdev_t handle, unsigned major,
unsigned minor, int readonly, int cdrom)
{
struct vbd *vbd;
struct block_device *bdev;
vbd = &blkif->vbd;
vbd->handle = handle;
vbd->readonly = readonly;
vbd->type = 0;
vbd->pdevice = MKDEV(major, minor);
bdev = open_by_devnum(vbd->pdevice,
vbd->readonly ? FMODE_READ : FMODE_WRITE);
if (IS_ERR(bdev)) {
DPRINTK("vbd_creat: device %08x could not be opened.\n",
vbd->pdevice);
return -ENOENT;
}
vbd->bdev = bdev;
vbd->size = vbd_size(vbd);
if (vbd->bdev->bd_disk == NULL) {
DPRINTK("vbd_creat: device %08x doesn't exist.\n",
vbd->pdevice);
vbd_free(vbd);
return -ENOENT;
}
if (vbd->bdev->bd_disk->flags & GENHD_FL_CD || cdrom)
vbd->type |= VDISK_CDROM;
if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
vbd->type |= VDISK_REMOVABLE;
DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
handle, blkif->domid);
return 0;
}
