From: Shuo Liu <[email protected]> The Service VM communicates with the hypervisor via conventional hypercalls. VMCALL instruction is used to make the hypercalls.
ACRN hypercall ABI: * Hypercall number is in R8 register. * Up to 2 parameters are in RDI and RSI registers. * Return value is in RAX register. Introduce the ACRN hypercall interfaces. Because GCC doesn't support R8 register as direct register constraints, use supported constraint as input with a explicit MOV to R8 in beginning of asm. Originally-by: Yakui Zhao <[email protected]> Signed-off-by: Shuo Liu <[email protected]> Reviewed-by: Reinette Chatre <[email protected]> Reviewed-by: Nick Desaulniers <[email protected]> Acked-by: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Dan Williams <[email protected]> Cc: Fengwei Yin <[email protected]> Cc: Zhi Wang <[email protected]> Cc: Zhenyu Wang <[email protected]> Cc: Yu Wang <[email protected]> Cc: Reinette Chatre <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Arvind Sankar <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Nick Desaulniers <[email protected]> Cc: Segher Boessenkool <[email protected]> --- arch/x86/include/asm/acrn.h | 54 +++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) diff --git a/arch/x86/include/asm/acrn.h b/arch/x86/include/asm/acrn.h index 127f20672c5d..e003a01b7c67 100644 --- a/arch/x86/include/asm/acrn.h +++ b/arch/x86/include/asm/acrn.h @@ -21,4 +21,58 @@ static inline u32 acrn_cpuid_base(void) return 0; } +/* + * Hypercalls for ACRN + * + * - VMCALL instruction is used to implement ACRN hypercalls. + * - ACRN hypercall ABI: + * - Hypercall number is passed in R8 register. + * - Up to 2 arguments are passed in RDI, RSI. + * - Return value will be placed in RAX. + * + * Because GCC doesn't support R8 register as direct register constraints, use + * supported constraint as input with a explicit MOV to R8 in beginning of asm. + */ +static inline long acrn_hypercall0(unsigned long hcall_id) +{ + long result; + + asm volatile("movl %1, %%r8d\n\t" + "vmcall\n\t" + : "=a" (result) + : "g" (hcall_id) + : "r8", "memory"); + + return result; +} + +static inline long acrn_hypercall1(unsigned long hcall_id, + unsigned long param1) +{ + long result; + + asm volatile("movl %1, %%r8d\n\t" + "vmcall\n\t" + : "=a" (result) + : "g" (hcall_id), "D" (param1) + : "r8", "memory"); + + return result; +} + +static inline long acrn_hypercall2(unsigned long hcall_id, + unsigned long param1, + unsigned long param2) +{ + long result; + + asm volatile("movl %1, %%r8d\n\t" + "vmcall\n\t" + : "=a" (result) + : "g" (hcall_id), "D" (param1), "S" (param2) + : "r8", "memory"); + + return result; +} + #endif /* _ASM_X86_ACRN_H */ -- 2.28.0
