From: Michael Kelley <mikel...@microsoft.com> Add ARM64-specific code to enable Hyper-V. This code includes: * Detecting Hyper-V and initializing the guest/Hyper-V interface * Setting up Hyper-V's synthetic clocks * Making hypercalls using the HVC instruction * Setting up VMbus and stimer0 interrupts * Setting up kexec and crash handlers This code is architecture dependent code and is mostly driven by architecture independent code in the VMbus driver in drivers/hv/hv.c and drivers/hv/vmbus_drv.c.
This code is built only when CONFIG_HYPERV is enabled. Signed-off-by: Michael Kelley <mikel...@microsoft.com> Signed-off-by: K. Y. Srinivasan <k...@microsoft.com> --- MAINTAINERS | 1 + arch/arm64/Makefile | 1 + arch/arm64/hyperv/Makefile | 2 + arch/arm64/hyperv/hv_hvc.S | 54 +++++ arch/arm64/hyperv/hv_init.c | 441 +++++++++++++++++++++++++++++++++++ arch/arm64/hyperv/mshyperv.c | 178 ++++++++++++++ 6 files changed, 677 insertions(+) create mode 100644 arch/arm64/hyperv/Makefile create mode 100644 arch/arm64/hyperv/hv_hvc.S create mode 100644 arch/arm64/hyperv/hv_init.c create mode 100644 arch/arm64/hyperv/mshyperv.c diff --git a/MAINTAINERS b/MAINTAINERS index 72f19cef4c48..326eeb32a0cd 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6837,6 +6837,7 @@ F: arch/x86/kernel/cpu/mshyperv.c F: arch/x86/hyperv F: arch/arm64/include/asm/hyperv-tlfs.h F: arch/arm64/include/asm/mshyperv.h +F: arch/arm64/hyperv F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/input/serio/hyperv-keyboard.c diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 6cb9fc7e9382..ad9ec0579553 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -106,6 +106,7 @@ core-y += arch/arm64/kernel/ arch/arm64/mm/ core-$(CONFIG_NET) += arch/arm64/net/ core-$(CONFIG_KVM) += arch/arm64/kvm/ core-$(CONFIG_XEN) += arch/arm64/xen/ +core-$(CONFIG_HYPERV) += arch/arm64/hyperv/ core-$(CONFIG_CRYPTO) += arch/arm64/crypto/ libs-y := arch/arm64/lib/ $(libs-y) core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile new file mode 100644 index 000000000000..988eda55330c --- /dev/null +++ b/arch/arm64/hyperv/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-y := hv_init.o hv_hvc.o mshyperv.o diff --git a/arch/arm64/hyperv/hv_hvc.S b/arch/arm64/hyperv/hv_hvc.S new file mode 100644 index 000000000000..82636969b4f2 --- /dev/null +++ b/arch/arm64/hyperv/hv_hvc.S @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Microsoft Hyper-V hypervisor invocation routines + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : Michael Kelley <mikel...@microsoft.com> + * + * 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 published + * 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 <linux/linkage.h> + + .text +/* + * Do the HVC instruction. For Hyper-V the argument is always 1. + * x0 contains the hypercall control value, while additional registers + * vary depending on the hypercall, and whether the hypercall arguments + * are in memory or in registers (a "fast" hypercall per the Hyper-V + * TLFS). When the arguments are in memory x1 is the guest physical + * address of the input arguments, and x2 is the guest physical + * address of the output arguments. When the arguments are in + * registers, the register values depends on the hypercall. Note + * that this version cannot return any values in registers. + */ +ENTRY(hv_do_hvc) + hvc #1 + ret +ENDPROC(hv_do_hvc) + +/* + * This variant of HVC invocation is for hv_get_vpreg and + * hv_get_vpreg_128. The input parameters are passed in registers + * along with a pointer in x4 to where the output result should + * be stored. The output is returned in x15 and x16. x18 is used as + * scratch space to avoid buildng a stack frame, as Hyper-V does + * not preserve registers x0-x17. + */ +ENTRY(hv_do_hvc_fast_get) + mov x18, x4 + hvc #1 + str x15,[x18] + str x16,[x18,#8] + ret +ENDPROC(hv_do_hvc_fast_get) diff --git a/arch/arm64/hyperv/hv_init.c b/arch/arm64/hyperv/hv_init.c new file mode 100644 index 000000000000..aa1a8c09d989 --- /dev/null +++ b/arch/arm64/hyperv/hv_init.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Initialization of the interface with Microsoft's Hyper-V hypervisor, + * and various low level utility routines for interacting with Hyper-V. + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : Michael Kelley <mikel...@microsoft.com> + * + * 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 published + * 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 <linux/types.h> +#include <linux/version.h> +#include <linux/export.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <linux/clocksource.h> +#include <linux/sched_clock.h> +#include <linux/acpi.h> +#include <linux/module.h> +#include <linux/hyperv.h> +#include <linux/slab.h> +#include <linux/cpuhotplug.h> +#include <linux/psci.h> +#include <asm-generic/bug.h> +#include <asm/hypervisor.h> +#include <asm/hyperv-tlfs.h> +#include <asm/mshyperv.h> +#include <asm/sysreg.h> +#include <clocksource/arm_arch_timer.h> + +static bool hyperv_initialized; +struct ms_hyperv_info ms_hyperv; +EXPORT_SYMBOL_GPL(ms_hyperv); + +static struct ms_hyperv_tsc_page *tsc_pg; + +struct ms_hyperv_tsc_page *hv_get_tsc_page(void) +{ + return tsc_pg; +} +EXPORT_SYMBOL_GPL(hv_get_tsc_page); + +static u64 read_hv_sched_clock_tsc(void) +{ + u64 current_tick = hv_read_tsc_page(tsc_pg); + + if (current_tick == U64_MAX) + current_tick = hv_get_vpreg(HV_REGISTER_TIME_REFCOUNT); + + return current_tick; +} + +static u64 read_hv_clock_tsc(struct clocksource *arg) +{ + u64 current_tick = hv_read_tsc_page(tsc_pg); + + if (current_tick == U64_MAX) + current_tick = hv_get_vpreg(HV_REGISTER_TIME_REFCOUNT); + + return current_tick; +} + +static struct clocksource hyperv_cs_tsc = { + .name = "hyperv_clocksource_tsc_page", + .rating = 400, + .read = read_hv_clock_tsc, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static u64 read_hv_sched_clock_msr(void) +{ + return hv_get_vpreg(HV_REGISTER_TIME_REFCOUNT); +} + +static u64 read_hv_clock_msr(struct clocksource *arg) +{ + return hv_get_vpreg(HV_REGISTER_TIME_REFCOUNT); +} + +static struct clocksource hyperv_cs_msr = { + .name = "hyperv_clocksource_msr", + .rating = 400, + .read = read_hv_clock_msr, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +struct clocksource *hyperv_cs; +EXPORT_SYMBOL_GPL(hyperv_cs); + +u32 *hv_vp_index; +EXPORT_SYMBOL_GPL(hv_vp_index); + +u32 hv_max_vp_index; + +static int hv_cpu_init(unsigned int cpu) +{ + u64 msr_vp_index; + + hv_get_vp_index(msr_vp_index); + + hv_vp_index[smp_processor_id()] = msr_vp_index; + + if (msr_vp_index > hv_max_vp_index) + hv_max_vp_index = msr_vp_index; + + return 0; +} + +/* + * This function is invoked via the ACPI clocksource probe mechanism. We + * don't actually use any values from the ACPI GTDT table, but we set up + * the Hyper-V synthetic clocksource and do other initialization for + * interacting with Hyper-V the first time. Using early_initcall to invoke + * this function is too late because interrupts are already enabled at that + * point, and sched_clock_register must run before interrupts are enabled. + * + * 1. Setup the guest ID. + * 2. Get features and hints info from Hyper-V + * 3. Setup per-cpu VP indices. + * 4. Register Hyper-V specific clocksource. + * 5. Register the scheduler clock. + */ + +static int __init hyperv_init(struct acpi_table_header *table) +{ + struct hv_get_vp_register_output result; + u32 a, b, c, d; + u64 guest_id; + int i; + + /* + * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will + * have the string "MsHyperV". + */ + if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) + return 1; + + /* Setup the guest ID */ + guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); + hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id); + + /* Get the features and hints from Hyper-V */ + hv_get_vpreg_128(HV_REGISTER_PRIVILEGES_AND_FEATURES, &result); + ms_hyperv.features = lower_32_bits(result.registervaluelow); + ms_hyperv.misc_features = upper_32_bits(result.registervaluehigh); + + hv_get_vpreg_128(HV_REGISTER_FEATURES, &result); + ms_hyperv.hints = lower_32_bits(result.registervaluelow); + + pr_info("Hyper-V: Features 0x%x, hints 0x%x\n", + ms_hyperv.features, ms_hyperv.hints); + + /* + * Direct mode is the only option for STIMERs provided Hyper-V + * on ARM64, so Hyper-V doesn't actually set the flag. But add the + * flag so the architecture independent code in drivers/hv/hv.c + * will correctly use that mode. + */ + ms_hyperv.misc_features |= HV_STIMER_DIRECT_MODE_AVAILABLE; + + /* + * Hyper-V on ARM64 doesn't support AutoEOI. Add the hint + * that tells architecture independent code not to use this + * feature. + */ + ms_hyperv.hints |= HV_DEPRECATING_AEOI_RECOMMENDED; + + /* Get information about the Hyper-V host version */ + hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result); + a = lower_32_bits(result.registervaluelow); + b = upper_32_bits(result.registervaluelow); + c = lower_32_bits(result.registervaluehigh); + d = upper_32_bits(result.registervaluehigh); + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", + b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24); + + /* Allocate percpu VP index */ + hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index), + GFP_KERNEL); + if (!hv_vp_index) + return 1; + + for (i = 0; i < num_possible_cpus(); i++) + hv_vp_index[i] = VP_INVAL; + + if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online", + hv_cpu_init, NULL) < 0) + goto free_vp_index; + + /* + * Try to set up what Hyper-V calls the "TSC reference page", which + * uses the ARM Generic Timer virtual counter with some scaling + * information to provide a fast and stable guest VM clocksource. + * If the TSC reference page can't be set up, fall back to reading + * the guest clock provided by Hyper-V's synthetic reference time + * register. + */ + if (ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE) { + + u64 tsc_msr; + phys_addr_t phys_addr; + + tsc_pg = __vmalloc(HV_HYP_PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); + if (tsc_pg) { + phys_addr = page_to_phys(vmalloc_to_page(tsc_pg)); + tsc_msr = hv_get_vpreg(HV_REGISTER_REFERENCE_TSC); + tsc_msr &= GENMASK_ULL(11, 0); + tsc_msr = tsc_msr | 0x1 | (u64)phys_addr; + hv_set_vpreg(HV_REGISTER_REFERENCE_TSC, tsc_msr); + hyperv_cs = &hyperv_cs_tsc; + sched_clock_register(read_hv_sched_clock_tsc, + 64, HV_CLOCK_HZ); + } + } + + if (!hyperv_cs && + (ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE)) { + hyperv_cs = &hyperv_cs_msr; + sched_clock_register(read_hv_sched_clock_msr, + 64, HV_CLOCK_HZ); + } + + if (hyperv_cs) { + hyperv_cs->archdata.vdso_direct = false; + clocksource_register_hz(hyperv_cs, HV_CLOCK_HZ); + } + + hyperv_initialized = true; + return 0; + +free_vp_index: + kfree(hv_vp_index); + hv_vp_index = NULL; + return 1; +} +TIMER_ACPI_DECLARE(hyperv, ACPI_SIG_GTDT, hyperv_init); + +/* + * This routine is called before kexec/kdump, it does the required cleanup. + */ +void hyperv_cleanup(void) +{ + /* Reset our OS id */ + hv_set_vpreg(HV_REGISTER_GUEST_OSID, 0); + +} +EXPORT_SYMBOL_GPL(hyperv_cleanup); + +/* + * hv_do_hypercall- Invoke the specified hypercall + */ +u64 hv_do_hypercall(u64 control, void *input, void *output) +{ + u64 input_address; + u64 output_address; + + input_address = input ? virt_to_phys(input) : 0; + output_address = output ? virt_to_phys(output) : 0; + return hv_do_hvc(control, input_address, output_address); +} +EXPORT_SYMBOL_GPL(hv_do_hypercall); + +/* + * hv_do_fast_hypercall8 -- Invoke the specified hypercall + * with arguments in registers instead of physical memory. + * Avoids the overhead of virt_to_phys for simple hypercalls. + */ + +u64 hv_do_fast_hypercall8(u16 code, u64 input) +{ + u64 control; + + control = (u64)code | HV_HYPERCALL_FAST_BIT; + return hv_do_hvc(control, input); +} +EXPORT_SYMBOL_GPL(hv_do_fast_hypercall8); + + +/* + * Set a single VP register to a 64-bit value. + */ +void hv_set_vpreg(u32 msr, u64 value) +{ + union hv_hypercall_status status; + + status.as_uint64 = hv_do_hvc( + HVCALL_SET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT | + HV_HYPERCALL_REP_COUNT_1, + HV_PARTITION_ID_SELF, + HV_VP_INDEX_SELF, + msr, + 0, + value, + 0); + + /* + * Something is fundamentally broken in the hypervisor if + * setting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(status.status != HV_STATUS_SUCCESS); +} +EXPORT_SYMBOL_GPL(hv_set_vpreg); + + +/* + * Get the value of a single VP register, and only the low order 64 bits. + */ +u64 hv_get_vpreg(u32 msr) +{ + union hv_hypercall_status status; + struct hv_get_vp_register_output output; + + status.as_uint64 = hv_do_hvc_fast_get( + HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT | + HV_HYPERCALL_REP_COUNT_1, + HV_PARTITION_ID_SELF, + HV_VP_INDEX_SELF, + msr, + &output); + + /* + * Something is fundamentally broken in the hypervisor if + * getting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(status.status != HV_STATUS_SUCCESS); + + return output.registervaluelow; +} +EXPORT_SYMBOL_GPL(hv_get_vpreg); + +/* + * Get the value of a single VP register that is 128 bits in size. This is a + * separate call in order to avoid complicating the calling sequence for + * the much more frequently used 64-bit version. + */ +void hv_get_vpreg_128(u32 msr, struct hv_get_vp_register_output *result) +{ + union hv_hypercall_status status; + + status.as_uint64 = hv_do_hvc_fast_get( + HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_FAST_BIT | + HV_HYPERCALL_REP_COUNT_1, + HV_PARTITION_ID_SELF, + HV_VP_INDEX_SELF, + msr, + result); + + /* + * Something is fundamentally broken in the hypervisor if + * getting a VP register fails. There's really no way to + * continue as a guest VM, so panic. + */ + BUG_ON(status.status != HV_STATUS_SUCCESS); + + return; + +} +EXPORT_SYMBOL_GPL(hv_get_vpreg_128); + +void hyperv_report_panic(struct pt_regs *regs, long err) +{ + static bool panic_reported; + u64 guest_id; + + /* + * We prefer to report panic on 'die' chain as we have proper + * registers to report, but if we miss it (e.g. on BUG()) we need + * to report it on 'panic'. + */ + if (panic_reported) + return; + panic_reported = true; + + guest_id = hv_get_vpreg(HV_REGISTER_GUEST_OSID); + + /* + * Hyper-V provides the ability to store only 5 values. + * Pick the passed in error value, the guest_id, and the PC. + * The first two general registers are added arbitrarily. + */ + hv_set_vpreg(HV_REGISTER_CRASH_P0, err); + hv_set_vpreg(HV_REGISTER_CRASH_P1, guest_id); + hv_set_vpreg(HV_REGISTER_CRASH_P2, regs->pc); + hv_set_vpreg(HV_REGISTER_CRASH_P3, regs->regs[0]); + hv_set_vpreg(HV_REGISTER_CRASH_P4, regs->regs[1]); + + /* + * Let Hyper-V know there is crash data available + */ + hv_set_vpreg(HV_REGISTER_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY); +} +EXPORT_SYMBOL_GPL(hyperv_report_panic); + +/* + * hyperv_report_panic_msg - report panic message to Hyper-V + * @pa: physical address of the panic page containing the message + * @size: size of the message in the page + */ +void hyperv_report_panic_msg(phys_addr_t pa, size_t size) +{ + /* + * P3 to contain the physical address of the panic page & P4 to + * contain the size of the panic data in that page. Rest of the + * registers are no-op when the NOTIFY_MSG flag is set. + */ + hv_set_vpreg(HV_REGISTER_CRASH_P0, 0); + hv_set_vpreg(HV_REGISTER_CRASH_P1, 0); + hv_set_vpreg(HV_REGISTER_CRASH_P2, 0); + hv_set_vpreg(HV_REGISTER_CRASH_P3, pa); + hv_set_vpreg(HV_REGISTER_CRASH_P4, size); + + /* + * Let Hyper-V know there is crash data available along with + * the panic message. + */ + hv_set_vpreg(HV_REGISTER_CRASH_CTL, + (HV_CRASH_CTL_CRASH_NOTIFY | HV_CRASH_CTL_CRASH_NOTIFY_MSG)); +} +EXPORT_SYMBOL_GPL(hyperv_report_panic_msg); + +bool hv_is_hyperv_initialized(void) +{ + return hyperv_initialized; +} +EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c new file mode 100644 index 000000000000..3ef055599412 --- /dev/null +++ b/arch/arm64/hyperv/mshyperv.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Core routines for interacting with Microsoft's Hyper-V hypervisor, + * including setting up VMbus and STIMER interrupts, and handling + * crashes and kexecs. These interactions are through a set of + * static "handler" variables set by the architecture independent + * VMbus and STIMER drivers. This design is used to meet x86/x64 + * requirements for avoiding direct linkages and allowing the VMbus + * and STIMER drivers to be unloaded and reloaded. + * + * Copyright (C) 2018, Microsoft, Inc. + * + * Author : Michael Kelley <mikel...@microsoft.com> + * + * 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 published + * 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 <linux/types.h> +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/kexec.h> +#include <linux/acpi.h> +#include <linux/ptrace.h> +#include <asm/hyperv-tlfs.h> +#include <asm/mshyperv.h> + +static void (*vmbus_handler)(void); +static void (*hv_stimer0_handler)(void); +static void (*hv_kexec_handler)(void); +static void (*hv_crash_handler)(struct pt_regs *regs); + +static int vmbus_irq; +static long __percpu *vmbus_evt; +static long __percpu *stimer0_evt; + +irqreturn_t hyperv_vector_handler(int irq, void *dev_id) +{ + if (vmbus_handler) + vmbus_handler(); + return IRQ_HANDLED; +} + +/* Must be done just once */ +void hv_setup_vmbus_irq(void (*handler)(void)) +{ + int result; + + vmbus_handler = handler; + vmbus_irq = acpi_register_gsi(NULL, HYPERVISOR_CALLBACK_VECTOR, + ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH); + if (vmbus_irq <= 0) { + pr_err("Can't register Hyper-V VMBus GSI. Error %d", + vmbus_irq); + vmbus_irq = 0; + return; + } + vmbus_evt = alloc_percpu(long); + result = request_percpu_irq(vmbus_irq, hyperv_vector_handler, + "Hyper-V VMbus", vmbus_evt); + if (result) { + pr_err("Can't request Hyper-V VMBus IRQ %d. Error %d", + vmbus_irq, result); + free_percpu(vmbus_evt); + acpi_unregister_gsi(vmbus_irq); + vmbus_irq = 0; + } +} +EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq); + +/* Must be done just once */ +void hv_remove_vmbus_irq(void) +{ + if (vmbus_irq) { + free_percpu_irq(vmbus_irq, vmbus_evt); + free_percpu(vmbus_evt); + acpi_unregister_gsi(vmbus_irq); + } +} +EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq); + +/* Must be done by each CPU */ +void hv_enable_vmbus_irq(void) +{ + enable_percpu_irq(vmbus_irq, 0); +} +EXPORT_SYMBOL_GPL(hv_enable_vmbus_irq); + +/* Must be done by each CPU */ +void hv_disable_vmbus_irq(void) +{ + disable_percpu_irq(vmbus_irq); +} +EXPORT_SYMBOL_GPL(hv_disable_vmbus_irq); + +/* Routines to do per-architecture handling of STIMER0 when in Direct Mode */ + +static irqreturn_t hv_stimer0_vector_handler(int irq, void *dev_id) +{ + if (hv_stimer0_handler) + hv_stimer0_handler(); + return IRQ_HANDLED; +} + +int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void)) +{ + int localirq; + int result; + + localirq = acpi_register_gsi(NULL, HV_STIMER0_IRQNR, + ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH); + if (localirq <= 0) { + pr_err("Can't register Hyper-V stimer0 GSI. Error %d", + localirq); + *irq = 0; + return -1; + } + stimer0_evt = alloc_percpu(long); + result = request_percpu_irq(localirq, hv_stimer0_vector_handler, + "Hyper-V stimer0", stimer0_evt); + if (result) { + pr_err("Can't request Hyper-V stimer0 IRQ %d. Error %d", + localirq, result); + free_percpu(stimer0_evt); + acpi_unregister_gsi(localirq); + *irq = 0; + return -1; + } + + hv_stimer0_handler = handler; + *vector = HV_STIMER0_IRQNR; + *irq = localirq; + return 0; +} +EXPORT_SYMBOL_GPL(hv_setup_stimer0_irq); + +void hv_remove_stimer0_irq(int irq) +{ + hv_stimer0_handler = NULL; + if (irq) { + free_percpu_irq(irq, stimer0_evt); + free_percpu(stimer0_evt); + acpi_unregister_gsi(irq); + } +} +EXPORT_SYMBOL_GPL(hv_remove_stimer0_irq); + +void hv_setup_kexec_handler(void (*handler)(void)) +{ + hv_kexec_handler = handler; +} +EXPORT_SYMBOL_GPL(hv_setup_kexec_handler); + +void hv_remove_kexec_handler(void) +{ + hv_kexec_handler = NULL; +} +EXPORT_SYMBOL_GPL(hv_remove_kexec_handler); + +void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)) +{ + hv_crash_handler = handler; +} +EXPORT_SYMBOL_GPL(hv_setup_crash_handler); + +void hv_remove_crash_handler(void) +{ + hv_crash_handler = NULL; +} +EXPORT_SYMBOL_GPL(hv_remove_crash_handler); -- 2.19.1