Support default block interfaces per QEMUMachine

There are QEMUMachines that have neither IF_IDE nor IF_SCSI as a
default/standard interface to their block devices / drives. Therefore,
this patch introduces a new field default_block_type per QEMUMachine
struct. The prior use_scsi field becomes thereby obsolete and is
replaced through .default_block_type = IF_SCSI.

This patch also changes the default for s390x to IF_VIRTIO and
removes an early hack that converts IF_IDE drives.
Other parties have already claimed interest (e.g. IF_SD for exynos)

To create a sane default, for machines that dont specify a
default_block_type, this patch makes IF_IDE = 0 and IF_NONE = 1.
I checked all users of IF_NONE (blockdev.c and ww/device-hotplug.c)
as well as IF_IDE and it seems that it is ok to change the defines -
in other words, I found no obvious (to me) assumption in the code
regarding IF_NONE==0. IF_NONE is only set if there is an
explicit if=none. Without if=* the interface becomes IF_DEFAULT.

I would suggest to have some additional care, e.g. by letting
this patch sit some days in the block tree.

Based on an initial patch from Einar Lueck <elelueck@de.ibm.com>

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: Igor Mitsyanko <i.mitsyanko@samsung.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Acked-by: Igor Mitsyanko <i.mitsyanko@samsung.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Christian Borntraeger 2012-11-20 15:30:34 +01:00 committed by Kevin Wolf
parent c208e8c2d8
commit 2d0d2837dc
17 changed files with 51 additions and 57 deletions

View file

@ -275,7 +275,7 @@ static bool do_check_io_limits(BlockIOLimit *io_limits)
return true;
}
DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
DriveInfo *drive_init(QemuOpts *opts, BlockInterfaceType block_default_type)
{
const char *buf;
const char *file = NULL;
@ -325,7 +325,7 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
return NULL;
}
} else {
type = default_to_scsi ? IF_SCSI : IF_IDE;
type = block_default_type;
}
max_devs = if_max_devs[type];