From eb914cfe72f4c948b2318b1381f6d2e08d43b63c Mon Sep 17 00:00:00 2001 From: Tianyu Lan Date: Thu, 19 Jul 2018 08:40:06 +0000 Subject: [PATCH] X86/Hyper-V: Add flush HvFlushGuestPhysicalAddressSpace hypercall support Hyper-V supports a pv hypercall HvFlushGuestPhysicalAddressSpace to flush nested VM address space mapping in l1 hypervisor and it's to reduce overhead of flushing ept tlb among vcpus. This patch is to implement it. Signed-off-by: Lan Tianyu Acked-by: K. Y. Srinivasan Signed-off-by: Paolo Bonzini --- arch/x86/hyperv/Makefile | 2 +- arch/x86/hyperv/nested.c | 53 ++++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/hyperv-tlfs.h | 8 ++++++ arch/x86/include/asm/mshyperv.h | 2 ++ 4 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 arch/x86/hyperv/nested.c diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile index b173d404e3df..b21ee65c4101 100644 --- a/arch/x86/hyperv/Makefile +++ b/arch/x86/hyperv/Makefile @@ -1,2 +1,2 @@ -obj-y := hv_init.o mmu.o +obj-y := hv_init.o mmu.o nested.o obj-$(CONFIG_X86_64) += hv_apic.o diff --git a/arch/x86/hyperv/nested.c b/arch/x86/hyperv/nested.c new file mode 100644 index 000000000000..08f914217518 --- /dev/null +++ b/arch/x86/hyperv/nested.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Hyper-V nested virtualization code. + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : Lan Tianyu + */ + + +#include +#include +#include +#include + +int hyperv_flush_guest_mapping(u64 as) +{ + struct hv_guest_mapping_flush **flush_pcpu; + struct hv_guest_mapping_flush *flush; + u64 status; + unsigned long flags; + int ret = -ENOTSUPP; + + if (!hv_hypercall_pg) + goto fault; + + local_irq_save(flags); + + flush_pcpu = (struct hv_guest_mapping_flush **) + this_cpu_ptr(hyperv_pcpu_input_arg); + + flush = *flush_pcpu; + + if (unlikely(!flush)) { + local_irq_restore(flags); + goto fault; + } + + flush->address_space = as; + flush->flags = 0; + + status = hv_do_hypercall(HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE, + flush, NULL); + local_irq_restore(flags); + + if (!(status & HV_HYPERCALL_RESULT_MASK)) + ret = 0; + +fault: + return ret; +} +EXPORT_SYMBOL_GPL(hyperv_flush_guest_mapping); diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h index b8c89265baf0..08e24f552030 100644 --- a/arch/x86/include/asm/hyperv-tlfs.h +++ b/arch/x86/include/asm/hyperv-tlfs.h @@ -309,6 +309,7 @@ struct ms_hyperv_tsc_page { #define HV_X64_MSR_REENLIGHTENMENT_CONTROL 0x40000106 /* Nested features (CPUID 0x4000000A) EAX */ +#define HV_X64_NESTED_GUEST_MAPPING_FLUSH BIT(18) #define HV_X64_NESTED_MSR_BITMAP BIT(19) struct hv_reenlightenment_control { @@ -350,6 +351,7 @@ struct hv_tsc_emulation_status { #define HVCALL_SEND_IPI_EX 0x0015 #define HVCALL_POST_MESSAGE 0x005c #define HVCALL_SIGNAL_EVENT 0x005d +#define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af #define HV_X64_MSR_VP_ASSIST_PAGE_ENABLE 0x00000001 #define HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT 12 @@ -741,6 +743,12 @@ struct ipi_arg_ex { struct hv_vpset vp_set; }; +/* HvFlushGuestPhysicalAddressSpace hypercalls */ +struct hv_guest_mapping_flush { + u64 address_space; + u64 flags; +}; + /* HvFlushVirtualAddressSpace, HvFlushVirtualAddressList hypercalls */ struct hv_tlb_flush { u64 address_space; diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 5a7375ed5f7c..2519f5de1e57 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -305,6 +305,7 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs); void set_hv_tscchange_cb(void (*cb)(void)); void clear_hv_tscchange_cb(void); void hyperv_stop_tsc_emulation(void); +int hyperv_flush_guest_mapping(u64 as); #ifdef CONFIG_X86_64 void hv_apic_init(void); @@ -324,6 +325,7 @@ static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu) { return NULL; } +static inline int hyperv_flush_guest_mapping(u64 as) { return -1; } #endif /* CONFIG_HYPERV */ #ifdef CONFIG_HYPERV_TSCPAGE -- 2.11.0