From: Shuo Liu <shuo.a....@intel.com>
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 <yakui.z...@intel.com>
Signed-off-by: Shuo Liu <shuo.a....@intel.com>
Reviewed-by: Reinette Chatre <reinette.cha...@intel.com>
Reviewed-by: Nick Desaulniers <ndesaulni...@google.com>
Acked-by: Borislav Petkov <b...@suse.de>
Cc: Dave Hansen <dave.han...@intel.com>
Cc: Sean Christopherson <sean.j.christopher...@intel.com>
Cc: Dan Williams <dan.j.willi...@intel.com>
Cc: Fengwei Yin <fengwei....@intel.com>
Cc: Zhi Wang <zhi.a.w...@intel.com>
Cc: Zhenyu Wang <zhen...@linux.intel.com>
Cc: Yu Wang <yu1.w...@intel.com>
Cc: Reinette Chatre <reinette.cha...@intel.com>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Arvind Sankar <nived...@alum.mit.edu>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Nick Desaulniers <ndesaulni...@google.com>
Cc: Segher Boessenkool <seg...@kernel.crashing.org>
---
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
