Re: [Xen-devel] [v4][PATCH 3/5] I440FX_PCI_DEVICE: add pci_type to index

["Chen, Tiejun" <tiejun.chen@xxxxxxxxx>]

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 <tiejun.chen@xxxxxxxxx>
> > > 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 <tiejun.chen@xxxxxxxxx>
> >
> > 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,
};

After that, we have two different QOM typenames of PCII440FXStates, 
TYPE_I440FX_PCI_DEVICE and TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE, 
right? So if you think we still should use this original,
#define I440FX_PCI_DEVICE(obj) \
        OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_PCI_DEVICE)

I really don't understand how to distinguish TYPE_I440FX_PCI_DEVICE and 
TYPE_XEN_IGD_PASSTHROUGH_I440FX_PCI_DEVICE just with I440FX_PCI_DEVICE(obj).
This should involve two places:

#1: static int i440fx_initfn(PCIDevice *dev)
{
    PCII440FXState *d = I440FX_PCI_DEVICE(dev);
    ...

#2: PCIBus *i440fx_init(const char *host_type, const char *pci_type,
                    PCII440FXState **pi440fx_state,
                    int *piix3_devfn,
                    ISABus **isa_bus, qemu_irq *pic,
                    MemoryRegion *address_space_mem,
                    MemoryRegion *address_space_io,
                    ram_addr_t ram_size,
                    ram_addr_t below_4g_mem_size,
                    ram_addr_t above_4g_mem_size,
                    MemoryRegion *pci_address_space,
                    MemoryRegion *ram_memory)
{
    ...
    PCIDevice *d;
    ...
    *pi440fx_state = I440FX_PCI_DEVICE(d);
    ...

So if you think I'm wrong please show me how to do just with 
I440FX_PCI_DEVICE() to work all scenarios from your point of view, then 
I'd like to followup yours to validate.
Thanks
Tiejun

> > +
> >   struct PCII440FXState {
> >       /*< private >*/
> >       PCIDevice parent_obj;
> > @@ -333,7 +336,7 @@ PCIBus *i440fx_init(const char *host_type, const char
> > *pci_type,
> >       qdev_init_nofail(dev);
> >
> >       d = pci_create_simple(b, 0, pci_type);
> > -    *pi440fx_state = I440FX_PCI_DEVICE(d);
> > +    *pi440fx_state = I440FX_PCI_DEVICE_FROM_TYPE(d, pci_type);
> >       f = *pi440fx_state;
> >       f->system_memory = address_space_mem;
> >       f->pci_address_space = pci_address_space;
> >
> >
> > Thanks
> > Tiejun
> >
> > > > ---
> > > >   hw/pci-host/piix.c | 10 +++++-----
> > > >   1 file changed, 5 insertions(+), 5 deletions(-)
> > > >
> > > > v4:
> > > >
> > > > * New patch to extend I440FX_PCI_DEVICE
> > > >
> > > > diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
> > > > index 0cd82b8..4330599 100644
> > > > --- a/hw/pci-host/piix.c
> > > > +++ b/hw/pci-host/piix.c
> > > > @@ -90,8 +90,8 @@ typedef struct PIIX3State {
> > > >       MemoryRegion rcr_mem;
> > > >   } PIIX3State;
> > > >
> > > > -#define I440FX_PCI_DEVICE(obj) \
> > > > -    OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_PCI_DEVICE)
> > > > +#define I440FX_PCI_DEVICE(obj, type) \
> > > > +    OBJECT_CHECK(PCII440FXState, (obj), type)
> > > >
> > > >   struct PCII440FXState {
> > > >       /*< private >*/
> > > > @@ -155,7 +155,7 @@ static void i440fx_set_smm(int val, void *arg)
> > > >   static void i440fx_write_config(PCIDevice *dev,
> > > >                                   uint32_t address, uint32_t val, int len)
> > > >   {
> > > > -    PCII440FXState *d = I440FX_PCI_DEVICE(dev);
> > > > +    PCII440FXState *d = I440FX_PCI_DEVICE(dev, TYPE_I440FX_PCI_DEVICE);
> > > >
> > > >       /* XXX: implement SMRAM.D_LOCK */
> > > >       pci_default_write_config(dev, address, val, len);
> > > > @@ -295,7 +295,7 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error 
> > > > **errp)
> > > >
> > > >   static int i440fx_initfn(PCIDevice *dev)
> > > >   {
> > > > -    PCII440FXState *d = I440FX_PCI_DEVICE(dev);
> > > > +    PCII440FXState *d = I440FX_PCI_DEVICE(dev, TYPE_I440FX_PCI_DEVICE);
> > > >
> > > >       dev->config[I440FX_SMRAM] = 0x02;
> > > >
> > > > @@ -333,7 +333,7 @@ PCIBus *i440fx_init(const char *host_type, const char 
> > > > *pci_type,
> > > >       qdev_init_nofail(dev);
> > > >
> > > >       d = pci_create_simple(b, 0, pci_type);
> > > > -    *pi440fx_state = I440FX_PCI_DEVICE(d);
> > > > +    *pi440fx_state = I440FX_PCI_DEVICE(d, pci_type);
> > > >       f = *pi440fx_state;
> > > >       f->system_memory = address_space_mem;
> > > >       f->pci_address_space = pci_address_space;
> > > > --
> > > > 1.9.1
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel