Re: [PATCH 2/2] pci: hyperv: Move retarget related struct definitions into tlfs

From: Boqun Feng
Date: Thu Jan 23 2020 - 05:40:14 EST


On Tue, Jan 21, 2020 at 10:25:47AM +0100, Vitaly Kuznetsov wrote:
[...]
> >
> > +#if IS_ENABLED(CONFIG_PCI_HYPERV)
> > +#define hv_set_msi_address_from_desc(msi_entry, msi_desc) \
> > +do { \
> > + (msi_entry)->address = (msi_desc)->msg.address_lo; \
> > +} while (0)
> > +
> > +#endif /* CONFIG_PCI_HYPERV */
>
> It seems to be pointless to put defines under #if IS_ENABLED(): in case
> it is not enabled and used you'll get a compilation error, in case it is
> enabled and not used no code is going to be generated anyways.
>

OK I will remove the #if IS_ENABLED() in the next version.

> > +
> > #else /* CONFIG_HYPERV */
> > static inline void hyperv_init(void) {}
> > static inline void hyperv_setup_mmu_ops(void) {}
> > diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> > index aacfcc90d929..2240f2b3643e 100644
> > --- a/drivers/pci/controller/pci-hyperv.c
> > +++ b/drivers/pci/controller/pci-hyperv.c
> > @@ -406,36 +406,6 @@ struct pci_eject_response {
> >
> > static int pci_ring_size = (4 * PAGE_SIZE);
> >
> > -struct hv_interrupt_entry {
> > - u32 source; /* 1 for MSI(-X) */
> > - u32 reserved1;
> > - u32 address;
> > - u32 data;
> > -};
> > -
> > -/*
> > - * flags for hv_device_interrupt_target.flags
> > - */
> > -#define HV_DEVICE_INTERRUPT_TARGET_MULTICAST 1
> > -#define HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET 2
> > -
> > -struct hv_device_interrupt_target {
> > - u32 vector;
> > - u32 flags;
> > - union {
> > - u64 vp_mask;
> > - struct hv_vpset vp_set;
> > - };
> > -};
> > -
> > -struct retarget_msi_interrupt {
> > - u64 partition_id; /* use "self" */
> > - u64 device_id;
> > - struct hv_interrupt_entry int_entry;
> > - u64 reserved2;
> > - struct hv_device_interrupt_target int_target;
> > -} __packed __aligned(8);
> > -
> > /*
> > * Driver specific state.
> > */
> > @@ -482,7 +452,7 @@ struct hv_pcibus_device {
> > struct workqueue_struct *wq;
> >
> > /* hypercall arg, must not cross page boundary */
> > - struct retarget_msi_interrupt retarget_msi_interrupt_params;
> > + struct hv_retarget_device_interrupt retarget_msi_interrupt_params;
> >
> > /*
> > * Don't put anything here: retarget_msi_interrupt_params must be last
> > @@ -1178,7 +1148,7 @@ static void hv_irq_unmask(struct irq_data *data)
> > {
> > struct msi_desc *msi_desc = irq_data_get_msi_desc(data);
> > struct irq_cfg *cfg = irqd_cfg(data);
> > - struct retarget_msi_interrupt *params;
> > + struct hv_retarget_device_interrupt *params;
> > struct hv_pcibus_device *hbus;
> > struct cpumask *dest;
> > cpumask_var_t tmp;
> > @@ -1200,8 +1170,8 @@ static void hv_irq_unmask(struct irq_data *data)
> > memset(params, 0, sizeof(*params));
> > params->partition_id = HV_PARTITION_ID_SELF;
> > params->int_entry.source = 1; /* MSI(-X) */
> > - params->int_entry.address = msi_desc->msg.address_lo;
> > - params->int_entry.data = msi_desc->msg.data;
> > + hv_set_msi_address_from_desc(&params->int_entry.msi_entry, msi_desc);
>
> I don't quite see why this hv_set_msi_address_from_desc() is needed at
> all.
>

I will add some description in the next version, the reason that
hv_set_msi_address_from_desc() is arm64 and x86 have different
hv_interrupt_entry formats. So a generic interface is needed so that
archs can have different ways to set ->address field from msi_desc.

Regards,
Boqun

> > + params->int_entry.msi_entry.data = msi_desc->msg.data;
> > params->device_id = (hbus->hdev->dev_instance.b[5] << 24) |
> > (hbus->hdev->dev_instance.b[4] << 16) |
> > (hbus->hdev->dev_instance.b[7] << 8) |
>
> --
> Vitaly
>