[PATCH 02/70] KVM: SVM: Add GHCB Accessor functions

Joerg Roedel
2020-03-19T09:21:03Z

From: Joerg Roedel <jroedel@suse.de>

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.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/include/asm/svm.h | 61 ++++++++++++++++++++++++++++++++++++++
1 file changed, 61 insertions(+)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index f36288c659b5..e4e9f6bacfaa 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -333,4 +333,65 @@ struct __attribute__ ((__packed__)) vmcb {

#define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP)

+/* GHCB Accessor functions */
+
+#define DEFINE_GHCB_INDICES(field) \
+ u16 idx = offsetof(struct vmcb_save_area, field) / 8; \
+ u16 byte_idx = idx / 8; \
+ u16 bit_idx = idx % 8; \
+ BUILD_BUG_ON(byte_idx > ARRAY_SIZE(ghcb->save.valid_bitmap));
+
+#define GHCB_SET_VALID(ghcb, field) \
+ { \
+ DEFINE_GHCB_INDICES(field) \
+ (ghcb)->save.valid_bitmap[byte_idx] |= BIT(bit_idx); \
+ }
+
+#define DEFINE_GHCB_SETTER(field) \
+ static inline void \
+ ghcb_set_##field(struct ghcb *ghcb, u64 value) \
+ { \
+ GHCB_SET_VALID(ghcb, field) \
+ (ghcb)->save.field = value; \
+ }
+
+#define DEFINE_GHCB_ACCESSORS(field) \
+ static inline bool ghcb_is_valid_##field(const struct ghcb *ghcb) \
+ { \
+ DEFINE_GHCB_INDICES(field) \
+ return !!((ghcb)->save.valid_bitmap[byte_idx] \
+ & BIT(bit_idx)); \
+ } \
+ \
+ static inline void \
+ ghcb_set_##field(struct ghcb *ghcb, u64 value) \
+ { \
+ GHCB_SET_VALID(ghcb, field) \
+ (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