2020-07-30 15:44:22

by Joerg Roedel

Subject: [PATCH v2 3/4] KVM: SVM: Add GHCB Accessor functions

From: Joerg Roedel <[email protected]>

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 <[email protected]>
---
arch/x86/include/asm/svm.h | 46 ++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 9a3e0b802716..8744817358bf 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -341,4 +341,50 @@ struct __attribute__ ((__packed__)) vmcb {

#define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP)

+/* GHCB Accessor functions */
+
+#define GHB_BITMAP_IDX(field) \
+ (offsetof(struct vmcb_save_area, field) / sizeof(u64))
+
+#define GHCB_SET_VALID(ghcb, field) \
+ __set_bit(GHB_BITMAP_IDX(field), (unsigned long *)&(ghcb)->save.valid_bitmap); \
+
+#define DEFINE_GHCB_ACCESSORS(field) \
+ static inline bool ghcb_##field##_is_valid(const struct ghcb *ghcb) \
+ { \
+ int idx = offsetof(struct vmcb_save_area, field) / sizeof(u64); \
+ return test_bit(idx, (unsigned long *)&(ghcb)->save.valid_bitmap); \
+ } \
+ \
+ 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

2020-07-31 15:21:48

by Sean Christopherson

Subject: Re: [PATCH v2 3/4] KVM: SVM: Add GHCB Accessor functions

On Thu, Jul 30, 2020 at 05:43:39PM +0200, Joerg Roedel wrote:
> From: Joerg Roedel <[email protected]>
>
> 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 <[email protected]>
> ---
> arch/x86/include/asm/svm.h | 46 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 46 insertions(+)
>
> diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
> index 9a3e0b802716..8744817358bf 100644
> --- a/arch/x86/include/asm/svm.h
> +++ b/arch/x86/include/asm/svm.h
> @@ -341,4 +341,50 @@ struct __attribute__ ((__packed__)) vmcb {
>
> #define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP)
>
> +/* GHCB Accessor functions */
> +
> +#define GHB_BITMAP_IDX(field) \
> + (offsetof(struct vmcb_save_area, field) / sizeof(u64))
> +
> +#define GHCB_SET_VALID(ghcb, field) \
> + __set_bit(GHB_BITMAP_IDX(field), (unsigned long *)&(ghcb)->save.valid_bitmap); \
> +
> +#define DEFINE_GHCB_ACCESSORS(field) \
> + static inline bool ghcb_##field##_is_valid(const struct ghcb *ghcb) \
> + { \
> + int idx = offsetof(struct vmcb_save_area, field) / sizeof(u64); \

This should also use GHB_BITMAP_IDX.

> + return test_bit(idx, (unsigned long *)&(ghcb)->save.valid_bitmap); \
> + } \
> + \
> + 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
>