From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tianyu Lan Subject: [PATCH V2 1/5] X86/Hyper-V: Add flush HvFlushGuestPhysicalAddressSpace hypercall support Date: Mon, 9 Jul 2018 09:02:34 +0000 Message-ID: <20180709090218.15342-2-Tianyu.Lan@microsoft.com> References: <20180709090218.15342-1-Tianyu.Lan@microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Cc: Tianyu Lan , KY Srinivasan , Haiyang Zhang , Stephen Hemminger , "tglx@linutronix.de" , "mingo@redhat.com" , "hpa@zytor.com" , "x86@kernel.org" , "pbonzini@redhat.com" , "rkrcmar@redhat.com" , "devel@linuxdriverproject.org" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "Michael Kelley (EOSG)" , "vkuznets@redhat.com" To: unlisted-recipients:; (no To-header on input) Return-path: In-Reply-To: <20180709090218.15342-1-Tianyu.Lan@microsoft.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org 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 --- arch/x86/hyperv/Makefile | 2 +- arch/x86/hyperv/nested.c | 64 ++++++++++++++++++++++++++++++++++= ++++ arch/x86/include/asm/hyperv-tlfs.h | 8 +++++ arch/x86/include/asm/mshyperv.h | 2 ++ 4 files changed, 75 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 :=3D hv_init.o mmu.o +obj-y :=3D hv_init.o mmu.o nested.o obj-$(CONFIG_X86_64) +=3D hv_apic.o diff --git a/arch/x86/hyperv/nested.c b/arch/x86/hyperv/nested.c new file mode 100644 index 000000000000..74dd38b5221d --- /dev/null +++ b/arch/x86/hyperv/nested.c @@ -0,0 +1,64 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Hyper-V nested virtualization code. + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : Lan Tianyu + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as publishe= d + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + * + */ + + +#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 =3D -EFAULT; + + if (!hv_hypercall_pg) + goto fault; + + local_irq_save(flags); + + flush_pcpu =3D (struct hv_guest_mapping_flush **) + this_cpu_ptr(hyperv_pcpu_input_arg); + + flush =3D *flush_pcpu; + + if (unlikely(!flush)) { + local_irq_restore(flags); + goto fault; + } + + flush->address_space =3D as; + flush->flags =3D 0; + + status =3D hv_do_hypercall(HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE, + flush, NULL); + local_irq_restore(flags); + + if (!(status & HV_HYPERCALL_RESULT_MASK)) + ret =3D 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/hype= rv-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 =20 /* Nested features (CPUID 0x4000000A) EAX */ +#define HV_X64_NESTED_GUEST_MAPPING_FLUSH BIT(18) #define HV_X64_NESTED_MSR_BITMAP BIT(19) =20 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 =20 #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; }; =20 +/* 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/mshyper= v.h index 3cd14311edfa..a6a615b49876 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -302,6 +302,7 @@ 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); =20 #ifdef CONFIG_X86_64 void hv_apic_init(void); @@ -321,6 +322,7 @@ static inline struct hv_vp_assist_page *hv_get_vp_assis= t_page(unsigned int cpu) { return NULL; } +static inline int hyperv_flush_guest_mapping(u64 as) { return -1; } #endif /* CONFIG_HYPERV */ =20 #ifdef CONFIG_HYPERV_TSCPAGE --=20 2.14.3