From: Maya Nakamura <m.maya.nakamura@gmail.com>
Date: Fri, 12 Jul 2019 08:14:47 +0000
Patch-mainline: v5.4-rc1
Subject: x86/hyperv: Create and use Hyper-V page definitions
Git-commit: fcd3f6222a4ece735d0b3ffb93f646eff693aa69
References: git-fixes

Define HV_HYP_PAGE_SHIFT, HV_HYP_PAGE_SIZE, and HV_HYP_PAGE_MASK because
the Linux guest page size and hypervisor page size concepts are different,
even though they happen to be the same value on x86.

Also, replace PAGE_SIZE with HV_HYP_PAGE_SIZE.

Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lkml.kernel.org/r/e95111629abf65d016e983f72494cbf110ce605f.1562916939.git.m.maya.nakamura@gmail.com
Acked-by: Olaf Hering <ohering@suse.de>
---
 arch/x86/include/asm/hyperv-tlfs.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -12,6 +12,16 @@
 #include <linux/types.h>
 #include <asm/page.h>
 
+/*
+ * While not explicitly listed in the TLFS, Hyper-V always runs with a page size
+ * of 4096. These definitions are used when communicating with Hyper-V using
+ * guest physical pages and guest physical page addresses, since the guest page
+ * size may not be 4096 on all architectures.
+ */
+#define HV_HYP_PAGE_SHIFT      12
+#define HV_HYP_PAGE_SIZE       BIT(HV_HYP_PAGE_SHIFT)
+#define HV_HYP_PAGE_MASK       (~(HV_HYP_PAGE_SIZE - 1))
+
 /*
  * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
  * is set by CPUID(HvCpuIdFunctionVersionAndFeatures).