On Thu, Feb 13, 2020 at 04:17:34AM +0000, Dexuan Cui wrote:

quoted

From: linux-hyperv-owner@vger.kernel.org
[off-list ref] On Behalf Of Boqun Feng
Sent: Sunday, February 9, 2020 7:40 PM

Currently, retarget_msi_interrupt and other structures it relys on are
defined in pci-hyperv.c. However, those structures are actually defined
in Hypervisor Top-Level Functional Specification [1] and may be
different in sizes of fields or layout from architecture to
architecture. Let's move those definitions into x86's tlfs header file
to support virtual PCI on non-x86 architectures in the future. Note that
"__packed" attribute is added to these structures during the movement
for the same reason as we use the attribute for other TLFS structures in
the header file: make sure the structures meet the specification and
avoid anything unexpected from the compilers.

Additionally, rename struct retarget_msi_interrupt to
hv_retarget_msi_interrupt for the consistent naming convention, also
mirroring the name in TLFS.

diff --git a/arch/x86/include/asm/hyperv-tlfs.h

b/arch/x86/include/asm/hyperv-tlfs.h
+
+struct hv_device_interrupt_target {
+	u32 vector;
+	u32 flags;
+	union {
+		u64 vp_mask;
+		struct hv_vpset vp_set;
+	};
+} __packed;
+
+/* HvRetargetDeviceInterrupt hypercall */

Reviewed-by: Dexuan Cui <decui@microsoft.com>

Thanks!

Just a small thing: would it be slightly better if we change the name 
in the above line to HVCALL_RETARGET_INTERRUPT ? 

HVCALL_RETARGET_INTERRUPT is a define, so it may help to locate the
actual value of the define here. And, HVCALL_RETARGET_INTERRUPT is
used several times in the patchset so IMO we'd better always use
the same name.

This might be a good suggestion, however, throughout the TLFS header,
camel case is more commonly used for referencing hypercall. For example:

	/* HvCallSendSyntheticClusterIpi hypercall */

So I think it's better to let it as it is for this patch, and later on,
if we reach a consensus, we can convert the names all together.

Thoughts?

Regards,
Boqun