[tip: x86/seves] KVM: SVM: Add GHCB Accessor functions

[tip-bot2 for Joerg Roedel]

The following commit has been merged into the x86/seves branch of tip:

Commit-ID:     3702c2f4eed2188440f65ecdfc89165106fe565d
Gitweb:        https://git.kernel.org/tip/3702c2f4eed2188440f65ecdfc89165106fe565d
Author:        Joerg Roedel <jroedel@xxxxxxx>
AuthorDate:    Mon, 07 Sep 2020 15:15:04 +02:00
Committer:     Borislav Petkov <bp@xxxxxxx>
CommitterDate: Mon, 07 Sep 2020 19:45:24 +02:00

KVM: SVM: Add GHCB Accessor functions

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>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20200907131613.12703-4-joro@xxxxxxxxxx
---
 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 acac55d..06e5258 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -345,4 +345,47 @@ 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