[PATCH v3 3/4] KVM: SVM: Add GHCB Accessor functions

From: Joerg Roedel
Date: Mon Aug 03 2020 - 08:45:37 EST


From: Joerg Roedel <jroedel@xxxxxxx>

Building a correct GHCB for the hypervisor requires setting valid bits
in the GHCB. Simplify that process by providing accessor functions to
set values and to update the valid bitmap and to check the valid bitmap
in KVM.

Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
arch/x86/include/asm/svm.h | 43 ++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 9a3e0b802716..71a308f1fbc8 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -341,4 +341,47 @@ struct __attribute__ ((__packed__)) vmcb {

#define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP)

+/* GHCB Accessor functions */
+
+#define GHCB_BITMAP_IDX(field) \
+ (offsetof(struct vmcb_save_area, field) / sizeof(u64))
+
+#define DEFINE_GHCB_ACCESSORS(field) \
+ static inline bool ghcb_##field##_is_valid(const struct ghcb *ghcb) \
+ { \
+ return test_bit(GHCB_BITMAP_IDX(field), \
+ (unsigned long *)&(ghcb)->save.valid_bitmap); \
+ } \
+ \
+ static inline void ghcb_set_##field(struct ghcb *ghcb, u64 value) \
+ { \
+ __set_bit(GHCB_BITMAP_IDX(field), \
+ (unsigned long *)&(ghcb)->save.valid_bitmap); \
+ ghcb->save.field = value; \
+ }
+
+DEFINE_GHCB_ACCESSORS(cpl)
+DEFINE_GHCB_ACCESSORS(rip)
+DEFINE_GHCB_ACCESSORS(rsp)
+DEFINE_GHCB_ACCESSORS(rax)
+DEFINE_GHCB_ACCESSORS(rcx)
+DEFINE_GHCB_ACCESSORS(rdx)
+DEFINE_GHCB_ACCESSORS(rbx)
+DEFINE_GHCB_ACCESSORS(rbp)
+DEFINE_GHCB_ACCESSORS(rsi)
+DEFINE_GHCB_ACCESSORS(rdi)
+DEFINE_GHCB_ACCESSORS(r8)
+DEFINE_GHCB_ACCESSORS(r9)
+DEFINE_GHCB_ACCESSORS(r10)
+DEFINE_GHCB_ACCESSORS(r11)
+DEFINE_GHCB_ACCESSORS(r12)
+DEFINE_GHCB_ACCESSORS(r13)
+DEFINE_GHCB_ACCESSORS(r14)
+DEFINE_GHCB_ACCESSORS(r15)
+DEFINE_GHCB_ACCESSORS(sw_exit_code)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_1)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_2)
+DEFINE_GHCB_ACCESSORS(sw_scratch)
+DEFINE_GHCB_ACCESSORS(xcr0)
+
#endif
--
2.17.1