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Merge feature/hyperv-arm64 (dbcb218)
* msft/feature/hyperv-arm64: Hyper-V: ARM64: Always use the Hyper-V hypercall interface Drivers: hv: Enable Hyper-V code to be built on ARM64 arm64: efi: Export screen_info arm64: hyperv: Initialize hypervisor on boot arm64: hyperv: Add kexec and panic handlers arm64: hyperv: Add Hyper-V clocksource/clockevent support arm64: hyperv: Add Hyper-V hypercall and register access utilities smccc: Add HVC call variant with result registers other than 0 thru 3 clocksource/drivers/hyper-v: Move handling of STIMER0 interrupts clocksource/drivers/hyper-v: Set clocksource rating based on Hyper-V feature clocksource/drivers/hyper-v: Handle sched_clock differences inline clocksource/drivers/hyper-v: Handle vDSO differences inline Drivers: hv: vmbus: Move handling of VMbus interrupts Drivers: hv: vmbus: Handle auto EOI quirk inline Drivers: hv: vmbus: Move hyperv_report_panic_msg to arch neutral code Drivers: hv: Redo Hyper-V synthetic MSR get/set functions x86/hyper-v: Move hv_message_type to architecture neutral module Drivers: hv: vmbus: Move Hyper-V page allocator to arch neutral code
2 parents 7a57795 + dbcb218 commit 13b2233

22 files changed

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‎MAINTAINERS‎

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@@ -8154,6 +8154,9 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git
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F: Documentation/ABI/stable/sysfs-bus-vmbus
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F: Documentation/ABI/testing/debugfs-hyperv
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F: Documentation/networking/device_drivers/ethernet/microsoft/netvsc.rst
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F: arch/arm64/hyperv
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F: arch/arm64/include/asm/hyperv-tlfs.h
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F: arch/arm64/include/asm/mshyperv.h
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F: arch/x86/hyperv
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F: arch/x86/include/asm/hyperv-tlfs.h
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F: arch/x86/include/asm/mshyperv.h

‎arch/arm64/Kbuild‎

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@@ -3,4 +3,5 @@ obj-y += kernel/ mm/
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obj-$(CONFIG_NET) += net/
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obj-$(CONFIG_KVM) += kvm/
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obj-$(CONFIG_XEN) += xen/
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obj-$(subst m,y,$(CONFIG_HYPERV)) += hyperv/
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obj-$(CONFIG_CRYPTO) += crypto/

‎arch/arm64/hyperv/Makefile‎

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# SPDX-License-Identifier: GPL-2.0
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obj-y := hv_core.o mshyperv.o hv_hvc.o

‎arch/arm64/hyperv/hv_core.c‎

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// SPDX-License-Identifier: GPL-2.0
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/*
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* Low level utility routines for interacting with Hyper-V.
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*
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* Copyright (C) 2021, Microsoft, Inc.
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*
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* Author : Michael Kelley <mikelley@microsoft.com>
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*/
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#include <linux/types.h>
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#include <linux/export.h>
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#include <linux/mm.h>
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#include <linux/hyperv.h>
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#include <linux/arm-smccc.h>
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#include <linux/module.h>
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#include <asm-generic/bug.h>
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#include <asm/hyperv-tlfs.h>
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#include <asm/mshyperv.h>
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/*
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* hv_do_hypercall- Invoke the specified hypercall
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*/
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u64 hv_do_hypercall(u64 control, void *input, void *output)
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{
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u64 input_address;
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u64 output_address;
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input_address = input ? virt_to_phys(input) : 0;
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output_address = output ? virt_to_phys(output) : 0;
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return hv_do_hvc(control, input_address, output_address);
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}
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EXPORT_SYMBOL_GPL(hv_do_hypercall);
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/*
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* hv_do_fast_hypercall8 -- Invoke the specified hypercall
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* with arguments in registers instead of physical memory.
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* Avoids the overhead of virt_to_phys for simple hypercalls.
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*/
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u64 hv_do_fast_hypercall8(u16 code, u64 input)
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{
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u64 control;
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control = (u64)code | HV_HYPERCALL_FAST_BIT;
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return hv_do_hvc(control, input);
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}
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EXPORT_SYMBOL_GPL(hv_do_fast_hypercall8);
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union hv_hypercall_status {
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u64 as_uint64;
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struct {
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u16 status;
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u16 reserved;
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u16 reps_completed; /* Low 12 bits */
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u16 reserved2;
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};
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};
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/*
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* Set a single VP register to a 64-bit value.
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*/
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void hv_set_vpreg(u32 msr, u64 value)
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{
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union hv_hypercall_status status;
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status.as_uint64 = hv_do_hvc(
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HVCALL_SET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT |
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HV_HYPERCALL_REP_COMP_1,
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HV_PARTITION_ID_SELF,
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HV_VP_INDEX_SELF,
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msr,
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0,
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value,
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0);
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/*
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* Something is fundamentally broken in the hypervisor if
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* setting a VP register fails. There's really no way to
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* continue as a guest VM, so panic.
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*/
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BUG_ON(status.status != HV_STATUS_SUCCESS);
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}
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EXPORT_SYMBOL_GPL(hv_set_vpreg);
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/*
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* Get the value of a single VP register. One version
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* returns just 64 bits and another returns the full 128 bits.
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* The two versions are separate to avoid complicating the
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* calling sequence for the more frequently used 64 bit version.
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*/
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void hv_get_vpreg_128(u32 msr, struct hv_get_vp_registers_output *result)
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{
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u64 status;
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status = hv_do_hvc_fast_get(
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HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT |
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HV_HYPERCALL_REP_COMP_1,
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HV_PARTITION_ID_SELF,
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HV_VP_INDEX_SELF,
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msr,
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result);
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/*
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* Something is fundamentally broken in the hypervisor if
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* getting a VP register fails. There's really no way to
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* continue as a guest VM, so panic.
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*/
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BUG_ON((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS);
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}
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EXPORT_SYMBOL_GPL(hv_get_vpreg_128);
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u64 hv_get_vpreg(u32 msr)
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{
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struct hv_get_vp_registers_output output;
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hv_get_vpreg_128(msr, &output);
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return output.as64.low;
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}
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EXPORT_SYMBOL_GPL(hv_get_vpreg);
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/*
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* hyperv_report_panic - report a panic to Hyper-V. This function uses
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* the older version of the Hyper-V interface that admittedly doesn't
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* pass enough information to be useful beyond just recording the
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* occurrence of a panic. The parallel hv_kmsg_dump() uses the
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* new interface that allows reporting 4 Kbytes of data, which is much
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* more useful. Hyper-V on ARM64 always supports the newer interface, but
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* we retain support for the older version because the sysadmin is allowed
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* to disable the newer version via sysctl in case of information security
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* concerns about the more verbose version.
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*/
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void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die)
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{
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static bool panic_reported;
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u64 guest_id;
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/* Don't report a panic to Hyper-V if we're not going to panic */
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if (in_die && !panic_on_oops)
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return;
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/*
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* We prefer to report panic on 'die' chain as we have proper
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* registers to report, but if we miss it (e.g. on BUG()) we need
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* to report it on 'panic'.
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*
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* Calling code in the 'die' and 'panic' paths ensures that only
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* one CPU is running this code, so no atomicity is needed.
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*/
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if (panic_reported)
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return;
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panic_reported = true;
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guest_id = hv_get_vpreg(HV_REGISTER_GUEST_OSID);
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/*
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* Hyper-V provides the ability to store only 5 values.
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* Pick the passed in error value, the guest_id, and the PC.
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* The first two general registers are added arbitrarily.
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*/
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hv_set_vpreg(HV_REGISTER_CRASH_P0, err);
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hv_set_vpreg(HV_REGISTER_CRASH_P1, guest_id);
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hv_set_vpreg(HV_REGISTER_CRASH_P2, regs->pc);
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hv_set_vpreg(HV_REGISTER_CRASH_P3, regs->regs[0]);
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hv_set_vpreg(HV_REGISTER_CRASH_P4, regs->regs[1]);
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/*
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* Let Hyper-V know there is crash data available
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*/
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hv_set_vpreg(HV_REGISTER_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY);
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}
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EXPORT_SYMBOL_GPL(hyperv_report_panic);

‎arch/arm64/hyperv/hv_hvc.S‎

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/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Microsoft Hyper-V hypervisor invocation routines
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*
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* Copyright (C) 2018, Microsoft, Inc.
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*
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* Author : Michael Kelley <mikelley@microsoft.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published
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* by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
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* NON INFRINGEMENT. See the GNU General Public License for more
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* details.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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.text
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/*
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* Do the HVC instruction. For Hyper-V the argument is always 1.
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* x0 contains the hypercall control value, while additional registers
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* vary depending on the hypercall, and whether the hypercall arguments
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* are in memory or in registers (a "fast" hypercall per the Hyper-V
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* TLFS). When the arguments are in memory x1 is the guest physical
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* address of the input arguments, and x2 is the guest physical
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* address of the output arguments. When the arguments are in
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* registers, the register values depends on the hypercall. Note
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* that this version cannot return any values in registers.
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*/
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SYM_FUNC_START(hv_do_hvc)
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hvc #1
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ret
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SYM_FUNC_END(hv_do_hvc)
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/*
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* This variant of HVC invocation is for hv_get_vpreg and
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* hv_get_vpreg_128. The input parameters are passed in registers
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* along with a pointer in x4 to where the output result should
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* be stored. The output is returned in x15 and x16. x19 is used as
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* scratch space to avoid buildng a stack frame, as Hyper-V does
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* not preserve registers x0-x17.
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*/
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SYM_FUNC_START(hv_do_hvc_fast_get)
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/*
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* Stash away x19 register so that it can be used as a scratch
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* register and pop it at the end.
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*/
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str x19, [sp, #-16]!
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mov x19, x4
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hvc #1
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str x15,[x19]
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str x16,[x19,#8]
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ldr x19, [sp], #16
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ret
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SYM_FUNC_END(hv_do_hvc_fast_get)

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