From mboxrd@z Thu Jan 1 00:00:00 1970 From: yakui.zhao@intel.com (Zhao Yakui) Date: Fri, 16 Aug 2019 10:25:44 +0800 Subject: [RFC PATCH 03/15] x86/acrn: Add hypercall for ACRN guest In-Reply-To: <1565922356-4488-1-git-send-email-yakui.zhao@intel.com> References: <1565922356-4488-1-git-send-email-yakui.zhao@intel.com> Message-ID: <1565922356-4488-4-git-send-email-yakui.zhao@intel.com> List-Id: Linux Driver Project Developer List When ACRN hypervisor is detected, the hypercall is needed so that the ACRN guest can query/config some settings. For example: it can be used to query the resources in hypervisor and manage the CPU/memory/device/ interrupt for guest operating system. On x86 it is implemented with the VMCALL instruction. Co-developed-by: Jason Chen CJ Signed-off-by: Jason Chen CJ Signed-off-by: Zhao Yakui --- 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 857e6244..ab97c3d 100644 --- a/arch/x86/include/asm/acrn.h +++ b/arch/x86/include/asm/acrn.h @@ -11,4 +11,58 @@ extern void acrn_hv_vector_handler(struct pt_regs *regs); extern void acrn_setup_intr_irq(void (*handler)(void)); extern void acrn_remove_intr_irq(void); + +/* + * Hypercalls for ACRN guest + * + * Hypercall number is passed in R8 register. + * Up to 2 arguments are passed in RDI, RSI. + * Return value will be placed in RAX. + */ +static inline long acrn_hypercall0(unsigned long hcall_id) +{ + long result; + + /* the hypercall is implemented with the VMCALL instruction. + * volatile qualifier is added to avoid that it is dropped + * because of compiler optimization. + */ + asm volatile("movq %[hcall_id], %%r8\n\t" + "vmcall\n\t" + : "=a" (result) + : [hcall_id] "g" (hcall_id) + : "r8"); + + return result; +} + +static inline long acrn_hypercall1(unsigned long hcall_id, + unsigned long param1) +{ + long result; + + asm volatile("movq %[hcall_id], %%r8\n\t" + "vmcall\n\t" + : "=a" (result) + : [hcall_id] "g" (hcall_id), "D" (param1) + : "r8"); + + return result; +} + +static inline long acrn_hypercall2(unsigned long hcall_id, + unsigned long param1, + unsigned long param2) +{ + long result; + + asm volatile("movq %[hcall_id], %%r8\n\t" + "vmcall\n\t" + : "=a" (result) + : [hcall_id] "g" (hcall_id), "D" (param1), "S" (param2) + : "r8"); + + return result; +} + #endif /* _ASM_X86_ACRN_H */ -- 2.7.4