bool blkconf_apply_backend_options(BlockConf *conf, bool readonly,
bool resizable, Error **errp)
{
BlockBackend *blk = conf->blk;
BlockdevOnError rerror, werror;
uint64_t perm, shared_perm;
bool wce;
int ret;
perm = BLK_PERM_CONSISTENT_READ;
if (!readonly) {
perm |= BLK_PERM_WRITE;
}
shared_perm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
BLK_PERM_GRAPH_MOD;
if (resizable) {
shared_perm |= BLK_PERM_RESIZE;
}
if (conf->share_rw) {
shared_perm |= BLK_PERM_WRITE;
}
ret = blk_set_perm(blk, perm, shared_perm, errp);
if (ret < 0) {
return false;
}
switch (conf->wce) {
case ON_OFF_AUTO_ON: wce = true; break;
case ON_OFF_AUTO_OFF: wce = false; break;
case ON_OFF_AUTO_AUTO: wce = blk_enable_write_cache(blk); break;
default:
abort();
}
rerror = conf->rerror;
if (rerror == BLOCKDEV_ON_ERROR_AUTO) {
rerror = blk_get_on_error(blk, true);
}
werror = conf->werror;
if (werror == BLOCKDEV_ON_ERROR_AUTO) {
werror = blk_get_on_error(blk, false);
}
blk_set_enable_write_cache(blk, wce);
blk_set_on_error(blk, rerror, werror);
return true;
}
static void scsi_generic_realize(SCSIDevice *s, Error **errp)
{
int rc;
int sg_version;
struct sg_scsi_id scsiid;
if (!s->conf.blk) {
error_setg(errp, "drive property not set");
return;
}
if (blk_get_on_error(s->conf.blk, 0) != BLOCKDEV_ON_ERROR_ENOSPC) {
error_setg(errp, "Device doesn't support drive option werror");
return;
}
if (blk_get_on_error(s->conf.blk, 1) != BLOCKDEV_ON_ERROR_REPORT) {
error_setg(errp, "Device doesn't support drive option rerror");
return;
}
/* check we are using a driver managing SG_IO (version 3 and after */
rc = blk_ioctl(s->conf.blk, SG_GET_VERSION_NUM, &sg_version);
if (rc < 0) {
error_setg(errp, "cannot get SG_IO version number: %s. "
"Is this a SCSI device?",
strerror(-rc));
return;
}
if (sg_version < 30000) {
error_setg(errp, "scsi generic interface too old");
return;
}
/* get LUN of the /dev/sg? */
if (blk_ioctl(s->conf.blk, SG_GET_SCSI_ID, &scsiid)) {
error_setg(errp, "SG_GET_SCSI_ID ioctl failed");
return;
}
/* define device state */
s->type = scsiid.scsi_type;
DPRINTF("device type %d\n", s->type);
switch (s->type) {
case TYPE_TAPE:
s->blocksize = get_stream_blocksize(s->conf.blk);
if (s->blocksize == -1) {
s->blocksize = 0;
}
break;
/* Make a guess for block devices, we'll fix it when the guest sends.
* READ CAPACITY. If they don't, they likely would assume these sizes
* anyway. (TODO: they could also send MODE SENSE).
*/
case TYPE_ROM:
case TYPE_WORM:
s->blocksize = 2048;
break;
default:
s->blocksize = 512;
break;
}
DPRINTF("block size %d\n", s->blocksize);
}
