Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit eb914cfe authored by Tianyu Lan's avatar Tianyu Lan Committed by Paolo Bonzini
Browse files

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: default avatarLan Tianyu <Tianyu.Lan@microsoft.com>
Acked-by: default avatarK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 3553ae56

arch/x86/hyperv/Makefile

+1 −1
Original line number Diff line number Diff line 
obj-y			:= hv_init.o mmu.o

obj-y			:= hv_init.o mmu.o nested.o

obj-$(CONFIG_X86_64)	+= hv_apic.o

arch/x86/hyperv/nested.c

0 → 100644
+53 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



/*

 * Hyper-V nested virtualization code.

 *

 * Copyright (C) 2018, Microsoft, Inc.

 *

 * Author : Lan Tianyu <Tianyu.Lan@microsoft.com>

 */





#include <linux/types.h>

#include <asm/hyperv-tlfs.h>

#include <asm/mshyperv.h>

#include <asm/tlbflush.h>



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);

arch/x86/include/asm/hyperv-tlfs.h

+8 −0
Original line number Diff line number Diff line
@@ -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;

arch/x86/include/asm/mshyperv.h

+2 −0
Original line number Diff line number Diff line
@@ -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