x86/hyperv: Add new hvcall guest address host visibility support (810a5212) · Commits · EulixOS / Software / Kernel

arch/x86/hyperv/Makefile

+1 −1

Original line number	Diff line number	Diff line
		# SPDX-License-Identifier: GPL-2.0-only
		obj-y := hv_init.o mmu.o nested.o irqdomain.o
		obj-y := hv_init.o mmu.o nested.o irqdomain.o ivm.o
		obj-$(CONFIG_X86_64) += hv_apic.o hv_proc.o

		ifdef CONFIG_X86_64

arch/x86/hyperv/hv_init.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -603,6 +603,12 @@ EXPORT_SYMBOL_GPL(hv_get_isolation_type);

		bool hv_is_isolation_supported(void)
		{
		if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
		return false;

		if (!hypervisor_is_type(X86_HYPER_MS_HYPERV))
		return false;

		return hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE;
		}

arch/x86/hyperv/ivm.c

0 → 100644

+105 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/*
		* Hyper-V Isolation VM interface with paravisor and hypervisor
		*
		* Author:
		* Tianyu Lan <Tianyu.Lan@microsoft.com>
		*/

		#include <linux/hyperv.h>
		#include <linux/types.h>
		#include <linux/bitfield.h>
		#include <linux/slab.h>
		#include <asm/io.h>
		#include <asm/mshyperv.h>

		/*
		* hv_mark_gpa_visibility - Set pages visible to host via hvcall.
		*
		* In Isolation VM, all guest memory is encrypted from host and guest
		* needs to set memory visible to host via hvcall before sharing memory
		* with host.
		*/
		static int hv_mark_gpa_visibility(u16 count, const u64 pfn[],
		enum hv_mem_host_visibility visibility)
		{
		struct hv_gpa_range_for_visibility *input_pcpu, input;
		u16 pages_processed;
		u64 hv_status;
		unsigned long flags;

		/* no-op if partition isolation is not enabled */
		if (!hv_is_isolation_supported())
		return 0;

		if (count > HV_MAX_MODIFY_GPA_REP_COUNT) {
		pr_err("Hyper-V: GPA count:%d exceeds supported:%lu\n", count,
		HV_MAX_MODIFY_GPA_REP_COUNT);
		return -EINVAL;
		}

		local_irq_save(flags);
		input_pcpu = (struct hv_gpa_range_for_visibility **)
		this_cpu_ptr(hyperv_pcpu_input_arg);
		input = *input_pcpu;
		if (unlikely(!input)) {
		local_irq_restore(flags);
		return -EINVAL;
		}

		input->partition_id = HV_PARTITION_ID_SELF;
		input->host_visibility = visibility;
		input->reserved0 = 0;
		input->reserved1 = 0;
		memcpy((void )input->gpa_page_list, pfn, count sizeof(*pfn));
		hv_status = hv_do_rep_hypercall(
		HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY, count,
		0, input, &pages_processed);
		local_irq_restore(flags);

		if (hv_result_success(hv_status))
		return 0;
		else
		return -EFAULT;
		}

		/*
		* hv_set_mem_host_visibility - Set specified memory visible to host.
		*
		* In Isolation VM, all guest memory is encrypted from host and guest
		* needs to set memory visible to host via hvcall before sharing memory
		* with host. This function works as wrap of hv_mark_gpa_visibility()
		* with memory base and size.
		*/
		int hv_set_mem_host_visibility(unsigned long kbuffer, int pagecount, bool visible)
		{
		enum hv_mem_host_visibility visibility = visible ?
		VMBUS_PAGE_VISIBLE_READ_WRITE : VMBUS_PAGE_NOT_VISIBLE;
		u64 *pfn_array;
		int ret = 0;
		int i, pfn;

		if (!hv_is_isolation_supported() \|\| !hv_hypercall_pg)
		return 0;

		pfn_array = kmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL);
		if (!pfn_array)
		return -ENOMEM;

		for (i = 0, pfn = 0; i < pagecount; i++) {
		pfn_array[pfn] = virt_to_hvpfn((void )kbuffer + i HV_HYP_PAGE_SIZE);
		pfn++;

		if (pfn == HV_MAX_MODIFY_GPA_REP_COUNT \|\| i == pagecount - 1) {
		ret = hv_mark_gpa_visibility(pfn, pfn_array,
		visibility);
		if (ret)
		goto err_free_pfn_array;
		pfn = 0;
		}
		}

		err_free_pfn_array:
		kfree(pfn_array);
		return ret;
		}

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

+17 −0

Original line number	Diff line number	Diff line
		@@ -276,6 +276,23 @@ enum hv_isolation_type {
		#define HV_X64_MSR_TIME_REF_COUNT HV_REGISTER_TIME_REF_COUNT
		#define HV_X64_MSR_REFERENCE_TSC HV_REGISTER_REFERENCE_TSC

		/* Hyper-V memory host visibility */
		enum hv_mem_host_visibility {
		VMBUS_PAGE_NOT_VISIBLE = 0,
		VMBUS_PAGE_VISIBLE_READ_ONLY = 1,
		VMBUS_PAGE_VISIBLE_READ_WRITE = 3
		};

		/* HvCallModifySparseGpaPageHostVisibility hypercall */
		#define HV_MAX_MODIFY_GPA_REP_COUNT ((PAGE_SIZE / sizeof(u64)) - 2)
		struct hv_gpa_range_for_visibility {
		u64 partition_id;
		u32 host_visibility:2;
		u32 reserved0:30;
		u32 reserved1;
		u64 gpa_page_list[HV_MAX_MODIFY_GPA_REP_COUNT];
		} __packed;

		/*
		* Declare the MSR used to setup pages used to communicate with the hypervisor.
		*/

arch/x86/include/asm/mshyperv.h

+6 −1

Original line number	Diff line number	Diff line
		@@ -192,7 +192,7 @@ struct irq_domain *hv_create_pci_msi_domain(void);
		int hv_map_ioapic_interrupt(int ioapic_id, bool level, int vcpu, int vector,
		struct hv_interrupt_entry *entry);
		int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry);

		int hv_set_mem_host_visibility(unsigned long addr, int numpages, bool visible);
		#else /* CONFIG_HYPERV */
		static inline void hyperv_init(void) {}
		static inline void hyperv_setup_mmu_ops(void) {}
		@@ -209,6 +209,11 @@ static inline int hyperv_flush_guest_mapping_range(u64 as,
		{
		return -1;
		}
		static inline int hv_set_mem_host_visibility(unsigned long addr, int numpages,
		bool visible)
		{
		return -1;
		}
		#endif /* CONFIG_HYPERV */