[PATCH v3 06/11] hv: hyperv.h: Introduce some hvpfn helper functions

From: Boqun Feng
Date: Thu Sep 10 2020 - 10:41:02 EST


When a guest communicate with the hypervisor, it must use HV_HYP_PAGE to
calculate PFN, so introduce a few hvpfn helper functions as the
counterpart of the page helper functions. This is the preparation for
supporting guest whose PAGE_SIZE is not 4k.

Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
---
include/linux/hyperv.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 6f4831212979..00c09d2ff9ad 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1687,4 +1687,9 @@ static inline unsigned long virt_to_hvpfn(void *addr)
return paddr >> HV_HYP_PAGE_SHIFT;
}

+#define NR_HV_HYP_PAGES_IN_PAGE (PAGE_SIZE / HV_HYP_PAGE_SIZE)
+#define offset_in_hvpage(ptr) ((unsigned long)(ptr) & ~HV_HYP_PAGE_MASK)
+#define HVPFN_UP(x) (((x) + HV_HYP_PAGE_SIZE-1) >> HV_HYP_PAGE_SHIFT)
+#define page_to_hvpfn(page) (page_to_pfn(page) * NR_HV_HYP_PAGES_IN_PAGE)
+
#endif /* _HYPERV_H */
--
2.28.0