[RFC PATCH v2 03/33] KVM: SVM: Add GHCB accessor functions for retrieving fields

[Tom Lendacky]

From: Tom Lendacky <thomas.lendacky@xxxxxxx>

Update the GHCB accessor functions to add functions for retrieve GHCB
fields by name. Update existing code to use the new accessor functions.

Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
---
 arch/x86/include/asm/svm.h   | 10 ++++++++++
 arch/x86/kernel/cpu/vmware.c | 12 ++++++------
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 71d630bb5e08..1edf24f51b53 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -379,6 +379,16 @@ struct vmcb {
 				(unsigned long *)&ghcb->save.valid_bitmap);	\
 	}									\
 										\
+	static inline u64 ghcb_get_##field(struct ghcb *ghcb)			\
+	{									\
+		return ghcb->save.field;					\
+	}									\
+										\
+	static inline u64 ghcb_get_##field##_if_valid(struct ghcb *ghcb)	\
+	{									\
+		return ghcb_##field##_is_valid(ghcb) ? ghcb->save.field : 0;	\
+	}									\
+										\
 	static inline void ghcb_set_##field(struct ghcb *ghcb, u64 value)	\
 	{									\
 		__set_bit(GHCB_BITMAP_IDX(field),				\
diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
index 924571fe5864..c6ede3b3d302 100644
--- a/arch/x86/kernel/cpu/vmware.c
+++ b/arch/x86/kernel/cpu/vmware.c
@@ -501,12 +501,12 @@ static bool vmware_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
 	      ghcb_rbp_is_valid(ghcb)))
 		return false;
 
-	regs->bx = ghcb->save.rbx;
-	regs->cx = ghcb->save.rcx;
-	regs->dx = ghcb->save.rdx;
-	regs->si = ghcb->save.rsi;
-	regs->di = ghcb->save.rdi;
-	regs->bp = ghcb->save.rbp;
+	regs->bx = ghcb_get_rbx(ghcb);
+	regs->cx = ghcb_get_rcx(ghcb);
+	regs->dx = ghcb_get_rdx(ghcb);
+	regs->si = ghcb_get_rsi(ghcb);
+	regs->di = ghcb_get_rdi(ghcb);
+	regs->bp = ghcb_get_rbp(ghcb);
 
 	return true;
 }
-- 
2.28.0