On Wed, Oct 24, 2012 at 03:12:36PM +0200, Markus Armbruster wrote:
> Jason Baron <jba...@redhat.com> writes:
>
> > From: Jason Baron <jba...@redhat.com>
> >
> > The current QEMUMachine definition has a 'use_scsi' field to indicate if a
> > machine type should use scsi by default. However, Q35 wants to use ahci by
> > default. Thus, introdue a new field in the QEMUMachine defintion, mach_if.
>
> Even though q35's desire to default to IF_AHCI is driving this patch,
> generalizing the default interface type makes sense on its own. Even if
> we IF_AHCI should turn out to need more discussion.
>
> > This field should be initialized by the machine type to the default
> > interface
> > type which it wants to use (IF_SCSI, IF_AHCI, etc.). If no mach_if is
> > defined,
> > or it is set to 'IF_DEFAULT' or 'IF_NONE', we currently assume IF_IDE.
> >
> > Please use 'static inline int get_mach_if(int mach_if)', when accesssing the
> > new mach_if field.
> >
> > Reviewed-by: Paolo Bonzini <pbonz...@redhat.com>
> > Signed-off-by: Jason Baron <jba...@redhat.com>
> > ---
> > blockdev.c | 4 ++--
> > blockdev.h | 19 +++++++++++++++++++
> > hw/boards.h | 2 +-
> > hw/device-hotplug.c | 2 +-
> > hw/highbank.c | 2 +-
> > hw/leon3.c | 2 +-
> > hw/mips_jazz.c | 4 ++--
> > hw/pc_sysfw.c | 2 +-
> > hw/puv3.c | 2 +-
> > hw/realview.c | 6 +++---
> > hw/spapr.c | 2 +-
> > hw/sun4m.c | 24 ++++++++++++------------
> > hw/versatilepb.c | 4 ++--
> > hw/vexpress.c | 4 ++--
> > hw/xilinx_zynq.c | 2 +-
> > vl.c | 20 +++++++++++---------
> > 16 files changed, 61 insertions(+), 40 deletions(-)
> >
> > diff --git a/blockdev.c b/blockdev.c
> > index 99828ad..c9a49c8 100644
> > --- a/blockdev.c
> > +++ b/blockdev.c
> > @@ -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, int mach_if)
>
> BlockInterfaceType mach_if
>
> Suggest to rename mach_if to something more descriptive. Kevin's
> default_drive_if works for me.
>
ok.
>
> > {
> > 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 = get_mach_if(mach_if);
> > }
> >
> > max_devs = if_max_devs[type];
> > diff --git a/blockdev.h b/blockdev.h
> > index 5f27b64..8b126ad 100644
> > --- a/blockdev.h
> > +++ b/blockdev.h
> > @@ -40,6 +40,22 @@ struct DriveInfo {
> > int refcount;
> > };
> >
> > +/*
> > + * Each qemu machine type defines a mach_if field for its default
> > + * interface type. If its unspecified, we set it to IF_IDE.
> > + */
> > +static inline int get_mach_if(int mach_if)
>
> BlockInterfaceType mach_if, and return type.
>
> > +{
> > + assert(mach_if < IF_COUNT);
> > + assert(mach_if >= IF_DEFAULT);
> > +
> > + if ((mach_if == IF_NONE) || (mach_if == IF_DEFAULT)) {
> > + return IF_IDE;
> > + }
> > +
> > + return mach_if;
> > +}
> > +
>
> I'm not sure we should map IF_NONE to IF_IDE.
>
> get_mach_if() should return an interface type the board supports. In
> theory, we could have a board that doesn't define any controllers, but
> still lets the user define some with -device (say because the board
> sports a PCI bus). Then IF_NONE would be the only interface type that
> makes any sense, and therefore the only sensible value of get_mach_if().
>
Ok, but no boards use IF_NONE in that sense currently. But planning for
the future is good :)
> If we drop the magic mapping of IF_NONE, only IF_DEFAULT is left, and
> that one's clearly marked "for use with drive_add() only". No real need
> for magic mapping then. Could drop get_mach_if() and use mach_if
> directly.
Meaning explicity set mach_if or default_drive_if to IF_IDE for all
machine types that are currently either IF_NONE, IF_DEFAULT, or not
explicitly defined?
Thanks,
-Jason
