diff mbox series

[v2,3/3] PCI: hv: Introduce hv_msi_entry

Message ID 20200203050313.69247-4-boqun.feng@gmail.com (mailing list archive)
State Superseded, archived
Headers show
Series PCI: hv: Generify pci-hyperv.c | expand

Commit Message

Boqun Feng Feb. 3, 2020, 5:03 a.m. UTC 
Add a new structure (hv_msi_entry), which is also defined int tlfs, to
describe the msi entry for HVCALL_RETARGET_INTERRUPT. The structure is
needed because its layout may be different from architecture to
architecture.

Also add a new generic interface hv_set_msi_address_from_desc() to allow
different archs to set the msi address from msi_desc.

No functional change, only preparation for the future support of virtual
PCI on non-x86 architectures.

Signed-off-by: Boqun Feng (Microsoft) <boqun.feng@gmail.com>
---
 arch/x86/include/asm/hyperv-tlfs.h  | 11 +++++++++--
 arch/x86/include/asm/mshyperv.h     |  5 +++++
 drivers/pci/controller/pci-hyperv.c |  4 ++--
 3 files changed, 16 insertions(+), 4 deletions(-)

Comments

Andrew Murray Feb. 3, 2020, 9:51 a.m. UTC | #1 
On Mon, Feb 03, 2020 at 01:03:13PM +0800, Boqun Feng wrote:
> Add a new structure (hv_msi_entry), which is also defined int tlfs, to

s/int/in the/ ?

> describe the msi entry for HVCALL_RETARGET_INTERRUPT. The structure is
> needed because its layout may be different from architecture to
> architecture.
> 
> Also add a new generic interface hv_set_msi_address_from_desc() to allow
> different archs to set the msi address from msi_desc.
> 
> No functional change, only preparation for the future support of virtual
> PCI on non-x86 architectures.
> 
> Signed-off-by: Boqun Feng (Microsoft) <boqun.feng@gmail.com>
> ---
>  arch/x86/include/asm/hyperv-tlfs.h  | 11 +++++++++--
>  arch/x86/include/asm/mshyperv.h     |  5 +++++
>  drivers/pci/controller/pci-hyperv.c |  4 ++--
>  3 files changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index 4a76e442481a..953b3ad38746 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -912,11 +912,18 @@ struct hv_partition_assist_pg {
>  	u32 tlb_lock_count;
>  };
>  
> +union hv_msi_entry {
> +	u64 as_uint64;
> +	struct {
> +		u32 address;
> +		u32 data;
> +	} __packed;
> +};
> +
>  struct hv_interrupt_entry {
>  	u32 source;			/* 1 for MSI(-X) */
>  	u32 reserved1;
> -	u32 address;
> -	u32 data;
> +	union hv_msi_entry msi_entry;
>  } __packed;
>  
>  /*
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 6b79515abb82..3bdaa3b6e68f 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -240,6 +240,11 @@ bool hv_vcpu_is_preempted(int vcpu);
>  static inline void hv_apic_init(void) {}
>  #endif
>  
> +#define hv_set_msi_address_from_desc(msi_entry, msi_desc)	\
> +do {								\
> +	(msi_entry)->address = (msi_desc)->msg.address_lo;	\
> +} while (0)

Given that this is a single statement, is there really a need for the do ; while(0) ?


> +
>  #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 0d9b74503577..2240f2b3643e 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -1170,8 +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);
> +	params->int_entry.msi_entry.data = msi_desc->msg.data;

If the layout may differ, then don't we also need a wrapper for data?

Thanks,

Andrew Murray

>  	params->device_id = (hbus->hdev->dev_instance.b[5] << 24) |
>  			   (hbus->hdev->dev_instance.b[4] << 16) |
>  			   (hbus->hdev->dev_instance.b[7] << 8) |
> -- 
> 2.24.1
>
Boqun Feng Feb. 3, 2020, 2:35 p.m. UTC | #2 
On Mon, Feb 03, 2020 at 09:51:40AM +0000, Andrew Murray wrote:
> On Mon, Feb 03, 2020 at 01:03:13PM +0800, Boqun Feng wrote:
> > Add a new structure (hv_msi_entry), which is also defined int tlfs, to
> 
> s/int/in the/ ?
> 

Good catch, will fix.

> > describe the msi entry for HVCALL_RETARGET_INTERRUPT. The structure is
> > needed because its layout may be different from architecture to
> > architecture.
> > 
> > Also add a new generic interface hv_set_msi_address_from_desc() to allow
> > different archs to set the msi address from msi_desc.
> > 
> > No functional change, only preparation for the future support of virtual
> > PCI on non-x86 architectures.
> > 
> > Signed-off-by: Boqun Feng (Microsoft) <boqun.feng@gmail.com>
> > ---
> >  arch/x86/include/asm/hyperv-tlfs.h  | 11 +++++++++--
> >  arch/x86/include/asm/mshyperv.h     |  5 +++++
> >  drivers/pci/controller/pci-hyperv.c |  4 ++--
> >  3 files changed, 16 insertions(+), 4 deletions(-)
> > 
> > diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> > index 4a76e442481a..953b3ad38746 100644
> > --- a/arch/x86/include/asm/hyperv-tlfs.h
> > +++ b/arch/x86/include/asm/hyperv-tlfs.h
> > @@ -912,11 +912,18 @@ struct hv_partition_assist_pg {
> >  	u32 tlb_lock_count;
> >  };
> >  
> > +union hv_msi_entry {
> > +	u64 as_uint64;
> > +	struct {
> > +		u32 address;
> > +		u32 data;
> > +	} __packed;
> > +};
> > +
> >  struct hv_interrupt_entry {
> >  	u32 source;			/* 1 for MSI(-X) */
> >  	u32 reserved1;
> > -	u32 address;
> > -	u32 data;
> > +	union hv_msi_entry msi_entry;
> >  } __packed;
> >  
> >  /*
> > diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> > index 6b79515abb82..3bdaa3b6e68f 100644
> > --- a/arch/x86/include/asm/mshyperv.h
> > +++ b/arch/x86/include/asm/mshyperv.h
> > @@ -240,6 +240,11 @@ bool hv_vcpu_is_preempted(int vcpu);
> >  static inline void hv_apic_init(void) {}
> >  #endif
> >  
> > +#define hv_set_msi_address_from_desc(msi_entry, msi_desc)	\
> > +do {								\
> > +	(msi_entry)->address = (msi_desc)->msg.address_lo;	\
> > +} while (0)
> 
> Given that this is a single statement, is there really a need for the do ; while(0) ?
> 

I choose to use do ; while (0) because I don't want code like the
following to be able to compile:

	hv_set_msi_address_from_desc(...) /* semicolon is missing */
	a = b;

But now think more about this, I think it's probably better to define
this as a function..

> 
> > +
> >  #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 0d9b74503577..2240f2b3643e 100644
> > --- a/drivers/pci/controller/pci-hyperv.c
> > +++ b/drivers/pci/controller/pci-hyperv.c
> > @@ -1170,8 +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);
> > +	params->int_entry.msi_entry.data = msi_desc->msg.data;
> 
> If the layout may differ, then don't we also need a wrapper for data?
> 

On x86 hv_msi_entry is:

	{
		u32 address;
		u32 data;
	}

and on ARM64 it is:

	{
		u64 address;
		u32 data;
		u32 reserved;
	}

So currently, setting msi_entry.data doesn't need a wrapper for
different archs. But now you mention it, probably a better way is to
provide a wrapper hv_set_msi_entry_from_desc(), which sets both address
and data instead of hv_set_msi_address_from_desc().

Thanks for looking into the whole patchset!

Regards,
Boqun

> Thanks,
> 
> Andrew Murray
> 
> >  	params->device_id = (hbus->hdev->dev_instance.b[5] << 24) |
> >  			   (hbus->hdev->dev_instance.b[4] << 16) |
> >  			   (hbus->hdev->dev_instance.b[7] << 8) |
> > -- 
> > 2.24.1
> >
Thomas Gleixner Feb. 3, 2020, 2:41 p.m. UTC | #3 
Boqun Feng <boqun.feng@gmail.com> writes:
>  /*
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 6b79515abb82..3bdaa3b6e68f 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -240,6 +240,11 @@ bool hv_vcpu_is_preempted(int vcpu);
>  static inline void hv_apic_init(void) {}
>  #endif
>  
> +#define hv_set_msi_address_from_desc(msi_entry, msi_desc)	\
> +do {								\
> +	(msi_entry)->address = (msi_desc)->msg.address_lo;	\
> +} while (0)

Any reason why this needs to be a macro? inlines are preferrred. They
are typesafe and readable.

Thanks,

        tglx
Boqun Feng Feb. 4, 2020, 2:13 a.m. UTC | #4 
On Mon, Feb 03, 2020 at 03:41:52PM +0100, Thomas Gleixner wrote:
> Boqun Feng <boqun.feng@gmail.com> writes:
> >  /*
> > diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> > index 6b79515abb82..3bdaa3b6e68f 100644
> > --- a/arch/x86/include/asm/mshyperv.h
> > +++ b/arch/x86/include/asm/mshyperv.h
> > @@ -240,6 +240,11 @@ bool hv_vcpu_is_preempted(int vcpu);
> >  static inline void hv_apic_init(void) {}
> >  #endif
> >  
> > +#define hv_set_msi_address_from_desc(msi_entry, msi_desc)	\
> > +do {								\
> > +	(msi_entry)->address = (msi_desc)->msg.address_lo;	\
> > +} while (0)
> 
> Any reason why this needs to be a macro? inlines are preferrred. They

Making it an inline function will require #include <linux/msi.h> in
mshyperv.h, which I was trying to avoid. But now it seems pointless. I
will make it an inline in next version.

Regards,
Boqun

> are typesafe and readable.
> 
> Thanks,
> 
>         tglx
diff mbox series

Patch

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 4a76e442481a..953b3ad38746 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -912,11 +912,18 @@  struct hv_partition_assist_pg {
 	u32 tlb_lock_count;
 };
 
+union hv_msi_entry {
+	u64 as_uint64;
+	struct {
+		u32 address;
+		u32 data;
+	} __packed;
+};
+
 struct hv_interrupt_entry {
 	u32 source;			/* 1 for MSI(-X) */
 	u32 reserved1;
-	u32 address;
-	u32 data;
+	union hv_msi_entry msi_entry;
 } __packed;
 
 /*
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 6b79515abb82..3bdaa3b6e68f 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -240,6 +240,11 @@  bool hv_vcpu_is_preempted(int vcpu);
 static inline void hv_apic_init(void) {}
 #endif
 
+#define hv_set_msi_address_from_desc(msi_entry, msi_desc)	\
+do {								\
+	(msi_entry)->address = (msi_desc)->msg.address_lo;	\
+} while (0)
+
 #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 0d9b74503577..2240f2b3643e 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -1170,8 +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);
+	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) |