From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59494) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XH7qQ-0002qV-RL for qemu-devel@nongnu.org; Tue, 12 Aug 2014 04:54:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XH7qM-0004dP-8E for qemu-devel@nongnu.org; Tue, 12 Aug 2014 04:54:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55577) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XH7qM-0004dJ-04 for qemu-devel@nongnu.org; Tue, 12 Aug 2014 04:54:10 -0400 Date: Tue, 12 Aug 2014 10:54:35 +0200 From: "Michael S. Tsirkin" Message-ID: <20140812085435.GA6440@redhat.com> References: <1407307835-9692-1-git-send-email-tiejun.chen@intel.com> <1407307835-9692-4-git-send-email-tiejun.chen@intel.com> <20140806094509.GB22307@redhat.com> <53E2009E.4080107@intel.com> <20140806210714.GD22307@redhat.com> <53E2D921.8040501@intel.com> <20140810202759.GA5199@redhat.com> <53E82F88.5020209@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53E82F88.5020209@intel.com> Subject: Re: [Qemu-devel] [v4][PATCH 3/5] I440FX_PCI_DEVICE: add pci_type to index List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Chen, Tiejun" Cc: pbonzini@redhat.com, xen-devel@lists.xensource.com, qemu-devel@nongnu.org, stefano.stabellini@eu.citrix.com On Mon, Aug 11, 2014 at 10:50:48AM +0800, Chen, Tiejun wrote: > On 2014/8/11 4:27, Michael S. Tsirkin wrote: > >On Thu, Aug 07, 2014 at 09:40:49AM +0800, Chen, Tiejun wrote: > >> > >> > >>On 2014/8/7 5:07, Michael S. Tsirkin wrote: > >>>On Wed, Aug 06, 2014 at 06:17:02PM +0800, Chen, Tiejun wrote: > >>>>On 2014/8/6 17:45, Michael S. Tsirkin wrote: > >>>>>On Wed, Aug 06, 2014 at 02:50:33PM +0800, Tiejun Chen wrote: > >>>>>>We need to use this index to reuse this macro later > >>>>>> > >>>>>>Signed-off-by: Tiejun Chen > >>>>> > >>>>>Which index? > >>>>>Most users don't need to change. > >>>>>Just open-code OBJECT_CHECK where necessary, or add > >>>>>a new wrapper. > >>>> > >>>>Okay so what about this? > >>>> > >>>> hw:pci-host:piix: define I440FX_PCI_DEVICE_FROM_TYPE > >>>> > >>>> We need to introduce I440FX_PCI_DEVICE_FROM_TYPE to get > >>>> object with type, then we can reuse i440fx_init() simply. > >>>> > >>>> Signed-off-by: Tiejun Chen > >>>> > >>>>diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c > >>>>index 0cd82b8..8c74653 100644 > >>>>--- a/hw/pci-host/piix.c > >>>>+++ b/hw/pci-host/piix.c > >>>>@@ -93,6 +93,9 @@ typedef struct PIIX3State { > >>>> #define I440FX_PCI_DEVICE(obj) \ > >>>> OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_PCI_DEVICE) > >>>> > >>>>+#define I440FX_PCI_DEVICE_FROM_TYPE(obj, type) \ > >>>>+ OBJECT_CHECK(PCII440FXState, (obj), type) > >>> > >>>This is just wrong. If you are casting to PCII440FXState, > >> > >>Why? We will have two different QOM typenames of PCII440FXStates. > >> > >>>there is no reason not to use TYPE_I440FX_PCI_DEVICE. > >> > >>As you know we already have this original, > >> > >>static const TypeInfo i440fx_info = { > >> .name = TYPE_I440FX_PCI_DEVICE, > >> .parent = TYPE_PCI_DEVICE, > >> .instance_size = sizeof(PCII440FXState), > >> .class_init = i440fx_class_init, > >>}; > >> > >>and in patch #4, we will register that new host bridge to IGD passthrough: > >> > >>static const TypeInfo xen_igd_passthrough_i440fx_info = { > >> .name = TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE, > >> .parent = TYPE_PCI_DEVICE, > >> .instance_size = sizeof(PCII440FXState), > >> .class_init = xen_igd_passthrough_i440fx_class_init, > >>}; > > > >My idea is to inherit TYPE_I440FX_PCI_DEVICE instead. > > So here, this mean xen_igd_passthrough_i440fx_info's parent should be > TYPE_I440FX_PCI_DEVICE, right? > > >Then you can reuse regular piix code which casts to > >TYPE_I440FX_PCI_DEVICE because > >TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE would > >be a subclass of TYPE_I440FX_PCI_DEVICE. > > > > So since then, we can reuse i440fx_initfn. > > As a summary, what we should do is like the following, > > xen:hw:pci-host:piix: create host bridge to passthrough > > Implement a pci host bridge specific to passthrough. Actually > this just inherits the standard one. > > This is based on http://patchwork.ozlabs.org/patch/363810/. > > Signed-off-by: Tiejun Chen > --- > hw/pci-host/piix.c | 28 ++++++++++++++++++++++++++++ > include/hw/i386/pc.h | 2 ++ > 2 files changed, 30 insertions(+) > > diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c > index 0cd82b8..2ccd9ee 100644 > --- a/hw/pci-host/piix.c > +++ b/hw/pci-host/piix.c > @@ -703,6 +703,33 @@ static const TypeInfo i440fx_info = { > .class_init = i440fx_class_init, > }; > > +static void xen_igd_passthrough_i440fx_class_init(ObjectClass *klass, void > *data) > +{ > + DeviceClass *dc = DEVICE_CLASS(klass); > + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); > + > + k->init = i440fx_initfn; > + k->vendor_id = PCI_VENDOR_ID_INTEL; > + k->device_id = PCI_DEVICE_ID_INTEL_82441; > + k->revision = 0x02; > + k->class_id = PCI_CLASS_BRIDGE_HOST; > + dc->desc = "IGD PT XEN Host bridge"; > + dc->vmsd = &vmstate_i440fx; > + /* > + * PCI-facing part of the host bridge, not usable without the > + * host-facing part, which can't be device_add'ed, yet. > + */ > + dc->cannot_instantiate_with_device_add_yet = true; > + dc->hotpluggable = false; > +} > + A bunch of code still duplicated here. Only override what you have to. > +static const TypeInfo xen_igd_passthrough_i440fx_info = { > + .name = TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE, > + .parent = TYPE_I440FX_PCI_DEVICE, > + .instance_size = sizeof(PCII440FXState), > + .class_init = xen_igd_passthrough_i440fx_class_init, > +}; > + > static const char *i440fx_pcihost_root_bus_path(PCIHostState *host_bridge, > PCIBus *rootbus) > { > @@ -744,6 +771,7 @@ static const TypeInfo i440fx_pcihost_info = { > static void i440fx_register_types(void) > { > type_register_static(&i440fx_info); > + type_register_static(&xen_igd_passthrough_i440fx_info); > type_register_static(&piix3_info); > type_register_static(&piix3_xen_info); > type_register_static(&i440fx_pcihost_info); > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h > index 11fb72f..de34aa6 100644 > --- a/include/hw/i386/pc.h > +++ b/include/hw/i386/pc.h > @@ -238,6 +238,8 @@ typedef struct PCII440FXState PCII440FXState; > #define TYPE_I440FX_PCI_HOST_BRIDGE "i440FX-pcihost" > #define TYPE_I440FX_PCI_DEVICE "i440FX" > > +#define TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE > "xen-igd-passthrough-i440FX" > + > PCIBus *i440fx_init(const char *host_type, const char *pci_type, > PCII440FXState **pi440fx_state, int *piix_devfn, > ISABus **isa_bus, qemu_irq *pic, > -- > 1.9.1 > > Thanks > Tiejun