Boqun Feng <boqun.feng@xxxxxxxxx> writes:
> For future support of virtual PCI on non-x86 architecture.
>
> Signed-off-by: Boqun Feng (Microsoft) <boqun.feng@xxxxxxxxx>
> ---
> arch/x86/include/asm/hyperv-tlfs.h | 38 +++++++++++++++++++++++++++++
> arch/x86/include/asm/mshyperv.h | 8 ++++++
> drivers/pci/controller/pci-hyperv.c | 38 +++--------------------------
> 3 files changed, 50 insertions(+), 34 deletions(-)
>
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index b9ebc20b2385..debe017ae748 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -912,4 +912,42 @@ struct hv_tlb_flush_ex {
> struct hv_partition_assist_pg {
> u32 tlb_lock_count;
> };
> +
> +union hv_msi_entry {
> + u64 as_uint64;
> + struct {
> + u32 address;
> + u32 data;
> + } __packed;
> +};
While Hyper-V code is full of this, I was once told that 'Union aliasing
is UB. Avoid it for good.' Maybe we should start getting rid of it
instead of adding more?
> +
> +struct hv_interrupt_entry {
> + u32 source; /* 1 for MSI(-X) */
> + u32 reserved1;
> + union hv_msi_entry msi_entry;
> +} __packed;
> +
> +/*
> + * 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;
> + };
> +} __packed;
> +
> +/* HvRetargetDeviceInterrupt hypercall */
> +struct hv_retarget_device_interrupt {
> + u64 partition_id;
> + u64 device_id;
> + struct hv_interrupt_entry int_entry;
> + u64 reserved2;
> + struct hv_device_interrupt_target int_target;
> +} __packed __aligned(8);
> #endif
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 6b79515abb82..d13319d82f6b 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -240,6 +240,14 @@ bool hv_vcpu_is_preempted(int vcpu);
> static inline void hv_apic_init(void) {}
> #endif
>
> +#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.
> +
> #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(¶ms->int_entry.msi_entry, msi_desc);
I don't quite see why this hv_set_msi_address_from_desc() is needed at
all.
> + 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
