v4.19.13 snapshot.
diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile
new file mode 100644
index 0000000..b21ee65
--- /dev/null
+++ b/arch/x86/hyperv/Makefile
@@ -0,0 +1,2 @@
+obj-y := hv_init.o mmu.o nested.o
+obj-$(CONFIG_X86_64) += hv_apic.o
diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
new file mode 100644
index 0000000..2c43e30
--- /dev/null
+++ b/arch/x86/hyperv/hv_apic.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Hyper-V specific APIC code.
+ *
+ * Copyright (C) 2018, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <kys@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/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/clockchips.h>
+#include <linux/hyperv.h>
+#include <linux/slab.h>
+#include <linux/cpuhotplug.h>
+#include <asm/hypervisor.h>
+#include <asm/mshyperv.h>
+#include <asm/apic.h>
+
+#include <asm/trace/hyperv.h>
+
+static struct apic orig_apic;
+
+static u64 hv_apic_icr_read(void)
+{
+ u64 reg_val;
+
+ rdmsrl(HV_X64_MSR_ICR, reg_val);
+ return reg_val;
+}
+
+static void hv_apic_icr_write(u32 low, u32 id)
+{
+ u64 reg_val;
+
+ reg_val = SET_APIC_DEST_FIELD(id);
+ reg_val = reg_val << 32;
+ reg_val |= low;
+
+ wrmsrl(HV_X64_MSR_ICR, reg_val);
+}
+
+static u32 hv_apic_read(u32 reg)
+{
+ u32 reg_val, hi;
+
+ switch (reg) {
+ case APIC_EOI:
+ rdmsr(HV_X64_MSR_EOI, reg_val, hi);
+ return reg_val;
+ case APIC_TASKPRI:
+ rdmsr(HV_X64_MSR_TPR, reg_val, hi);
+ return reg_val;
+
+ default:
+ return native_apic_mem_read(reg);
+ }
+}
+
+static void hv_apic_write(u32 reg, u32 val)
+{
+ switch (reg) {
+ case APIC_EOI:
+ wrmsr(HV_X64_MSR_EOI, val, 0);
+ break;
+ case APIC_TASKPRI:
+ wrmsr(HV_X64_MSR_TPR, val, 0);
+ break;
+ default:
+ native_apic_mem_write(reg, val);
+ }
+}
+
+static void hv_apic_eoi_write(u32 reg, u32 val)
+{
+ wrmsr(HV_X64_MSR_EOI, val, 0);
+}
+
+/*
+ * IPI implementation on Hyper-V.
+ */
+static bool __send_ipi_mask_ex(const struct cpumask *mask, int vector)
+{
+ struct hv_send_ipi_ex **arg;
+ struct hv_send_ipi_ex *ipi_arg;
+ unsigned long flags;
+ int nr_bank = 0;
+ int ret = 1;
+
+ if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
+ return false;
+
+ local_irq_save(flags);
+ arg = (struct hv_send_ipi_ex **)this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ ipi_arg = *arg;
+ if (unlikely(!ipi_arg))
+ goto ipi_mask_ex_done;
+
+ ipi_arg->vector = vector;
+ ipi_arg->reserved = 0;
+ ipi_arg->vp_set.valid_bank_mask = 0;
+
+ if (!cpumask_equal(mask, cpu_present_mask)) {
+ ipi_arg->vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ nr_bank = cpumask_to_vpset(&(ipi_arg->vp_set), mask);
+ }
+ if (nr_bank < 0)
+ goto ipi_mask_ex_done;
+ if (!nr_bank)
+ ipi_arg->vp_set.format = HV_GENERIC_SET_ALL;
+
+ ret = hv_do_rep_hypercall(HVCALL_SEND_IPI_EX, 0, nr_bank,
+ ipi_arg, NULL);
+
+ipi_mask_ex_done:
+ local_irq_restore(flags);
+ return ((ret == 0) ? true : false);
+}
+
+static bool __send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ int cur_cpu, vcpu;
+ struct hv_send_ipi ipi_arg;
+ int ret = 1;
+
+ trace_hyperv_send_ipi_mask(mask, vector);
+
+ if (cpumask_empty(mask))
+ return true;
+
+ if (!hv_hypercall_pg)
+ return false;
+
+ if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR))
+ return false;
+
+ /*
+ * From the supplied CPU set we need to figure out if we can get away
+ * with cheaper HVCALL_SEND_IPI hypercall. This is possible when the
+ * highest VP number in the set is < 64. As VP numbers are usually in
+ * ascending order and match Linux CPU ids, here is an optimization:
+ * we check the VP number for the highest bit in the supplied set first
+ * so we can quickly find out if using HVCALL_SEND_IPI_EX hypercall is
+ * a must. We will also check all VP numbers when walking the supplied
+ * CPU set to remain correct in all cases.
+ */
+ if (hv_cpu_number_to_vp_number(cpumask_last(mask)) >= 64)
+ goto do_ex_hypercall;
+
+ ipi_arg.vector = vector;
+ ipi_arg.cpu_mask = 0;
+
+ for_each_cpu(cur_cpu, mask) {
+ vcpu = hv_cpu_number_to_vp_number(cur_cpu);
+ if (vcpu == VP_INVAL)
+ return false;
+
+ /*
+ * This particular version of the IPI hypercall can
+ * only target upto 64 CPUs.
+ */
+ if (vcpu >= 64)
+ goto do_ex_hypercall;
+
+ __set_bit(vcpu, (unsigned long *)&ipi_arg.cpu_mask);
+ }
+
+ ret = hv_do_fast_hypercall16(HVCALL_SEND_IPI, ipi_arg.vector,
+ ipi_arg.cpu_mask);
+ return ((ret == 0) ? true : false);
+
+do_ex_hypercall:
+ return __send_ipi_mask_ex(mask, vector);
+}
+
+static bool __send_ipi_one(int cpu, int vector)
+{
+ struct cpumask mask = CPU_MASK_NONE;
+
+ cpumask_set_cpu(cpu, &mask);
+ return __send_ipi_mask(&mask, vector);
+}
+
+static void hv_send_ipi(int cpu, int vector)
+{
+ if (!__send_ipi_one(cpu, vector))
+ orig_apic.send_IPI(cpu, vector);
+}
+
+static void hv_send_ipi_mask(const struct cpumask *mask, int vector)
+{
+ if (!__send_ipi_mask(mask, vector))
+ orig_apic.send_IPI_mask(mask, vector);
+}
+
+static void hv_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
+{
+ unsigned int this_cpu = smp_processor_id();
+ struct cpumask new_mask;
+ const struct cpumask *local_mask;
+
+ cpumask_copy(&new_mask, mask);
+ cpumask_clear_cpu(this_cpu, &new_mask);
+ local_mask = &new_mask;
+ if (!__send_ipi_mask(local_mask, vector))
+ orig_apic.send_IPI_mask_allbutself(mask, vector);
+}
+
+static void hv_send_ipi_allbutself(int vector)
+{
+ hv_send_ipi_mask_allbutself(cpu_online_mask, vector);
+}
+
+static void hv_send_ipi_all(int vector)
+{
+ if (!__send_ipi_mask(cpu_online_mask, vector))
+ orig_apic.send_IPI_all(vector);
+}
+
+static void hv_send_ipi_self(int vector)
+{
+ if (!__send_ipi_one(smp_processor_id(), vector))
+ orig_apic.send_IPI_self(vector);
+}
+
+void __init hv_apic_init(void)
+{
+ if (ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) {
+ pr_info("Hyper-V: Using IPI hypercalls\n");
+ /*
+ * Set the IPI entry points.
+ */
+ orig_apic = *apic;
+
+ apic->send_IPI = hv_send_ipi;
+ apic->send_IPI_mask = hv_send_ipi_mask;
+ apic->send_IPI_mask_allbutself = hv_send_ipi_mask_allbutself;
+ apic->send_IPI_allbutself = hv_send_ipi_allbutself;
+ apic->send_IPI_all = hv_send_ipi_all;
+ apic->send_IPI_self = hv_send_ipi_self;
+ }
+
+ if (ms_hyperv.hints & HV_X64_APIC_ACCESS_RECOMMENDED) {
+ pr_info("Hyper-V: Using MSR based APIC access\n");
+ apic_set_eoi_write(hv_apic_eoi_write);
+ apic->read = hv_apic_read;
+ apic->write = hv_apic_write;
+ apic->icr_write = hv_apic_icr_write;
+ apic->icr_read = hv_apic_icr_read;
+ }
+}
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
new file mode 100644
index 0000000..20c876c
--- /dev/null
+++ b/arch/x86/hyperv/hv_init.c
@@ -0,0 +1,476 @@
+/*
+ * X86 specific Hyper-V initialization code.
+ *
+ * Copyright (C) 2016, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <kys@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 <asm/apic.h>
+#include <asm/desc.h>
+#include <asm/hypervisor.h>
+#include <asm/hyperv-tlfs.h>
+#include <asm/mshyperv.h>
+#include <linux/version.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/clockchips.h>
+#include <linux/hyperv.h>
+#include <linux/slab.h>
+#include <linux/cpuhotplug.h>
+
+#ifdef CONFIG_HYPERV_TSCPAGE
+
+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_clock_tsc(struct clocksource *arg)
+{
+ u64 current_tick = hv_read_tsc_page(tsc_pg);
+
+ if (current_tick == U64_MAX)
+ rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
+
+ 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,
+};
+#endif
+
+static u64 read_hv_clock_msr(struct clocksource *arg)
+{
+ u64 current_tick;
+ /*
+ * Read the partition counter to get the current tick count. This count
+ * is set to 0 when the partition is created and is incremented in
+ * 100 nanosecond units.
+ */
+ rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
+ return current_tick;
+}
+
+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,
+};
+
+void *hv_hypercall_pg;
+EXPORT_SYMBOL_GPL(hv_hypercall_pg);
+struct clocksource *hyperv_cs;
+EXPORT_SYMBOL_GPL(hyperv_cs);
+
+u32 *hv_vp_index;
+EXPORT_SYMBOL_GPL(hv_vp_index);
+
+struct hv_vp_assist_page **hv_vp_assist_page;
+EXPORT_SYMBOL_GPL(hv_vp_assist_page);
+
+void __percpu **hyperv_pcpu_input_arg;
+EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
+
+u32 hv_max_vp_index;
+
+static int hv_cpu_init(unsigned int cpu)
+{
+ u64 msr_vp_index;
+ struct hv_vp_assist_page **hvp = &hv_vp_assist_page[smp_processor_id()];
+ void **input_arg;
+
+ input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
+ *input_arg = page_address(alloc_page(GFP_KERNEL));
+
+ 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;
+
+ if (!hv_vp_assist_page)
+ return 0;
+
+ if (!*hvp)
+ *hvp = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL);
+
+ if (*hvp) {
+ u64 val;
+
+ val = vmalloc_to_pfn(*hvp);
+ val = (val << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) |
+ HV_X64_MSR_VP_ASSIST_PAGE_ENABLE;
+
+ wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, val);
+ }
+
+ return 0;
+}
+
+static void (*hv_reenlightenment_cb)(void);
+
+static void hv_reenlightenment_notify(struct work_struct *dummy)
+{
+ struct hv_tsc_emulation_status emu_status;
+
+ rdmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status);
+
+ /* Don't issue the callback if TSC accesses are not emulated */
+ if (hv_reenlightenment_cb && emu_status.inprogress)
+ hv_reenlightenment_cb();
+}
+static DECLARE_DELAYED_WORK(hv_reenlightenment_work, hv_reenlightenment_notify);
+
+void hyperv_stop_tsc_emulation(void)
+{
+ u64 freq;
+ struct hv_tsc_emulation_status emu_status;
+
+ rdmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status);
+ emu_status.inprogress = 0;
+ wrmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status);
+
+ rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq);
+ tsc_khz = div64_u64(freq, 1000);
+}
+EXPORT_SYMBOL_GPL(hyperv_stop_tsc_emulation);
+
+static inline bool hv_reenlightenment_available(void)
+{
+ /*
+ * Check for required features and priviliges to make TSC frequency
+ * change notifications work.
+ */
+ return ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
+ ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE &&
+ ms_hyperv.features & HV_X64_ACCESS_REENLIGHTENMENT;
+}
+
+__visible void __irq_entry hyperv_reenlightenment_intr(struct pt_regs *regs)
+{
+ entering_ack_irq();
+
+ inc_irq_stat(irq_hv_reenlightenment_count);
+
+ schedule_delayed_work(&hv_reenlightenment_work, HZ/10);
+
+ exiting_irq();
+}
+
+void set_hv_tscchange_cb(void (*cb)(void))
+{
+ struct hv_reenlightenment_control re_ctrl = {
+ .vector = HYPERV_REENLIGHTENMENT_VECTOR,
+ .enabled = 1,
+ .target_vp = hv_vp_index[smp_processor_id()]
+ };
+ struct hv_tsc_emulation_control emu_ctrl = {.enabled = 1};
+
+ if (!hv_reenlightenment_available()) {
+ pr_warn("Hyper-V: reenlightenment support is unavailable\n");
+ return;
+ }
+
+ hv_reenlightenment_cb = cb;
+
+ /* Make sure callback is registered before we write to MSRs */
+ wmb();
+
+ wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl));
+ wrmsrl(HV_X64_MSR_TSC_EMULATION_CONTROL, *((u64 *)&emu_ctrl));
+}
+EXPORT_SYMBOL_GPL(set_hv_tscchange_cb);
+
+void clear_hv_tscchange_cb(void)
+{
+ struct hv_reenlightenment_control re_ctrl;
+
+ if (!hv_reenlightenment_available())
+ return;
+
+ rdmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *(u64 *)&re_ctrl);
+ re_ctrl.enabled = 0;
+ wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *(u64 *)&re_ctrl);
+
+ hv_reenlightenment_cb = NULL;
+}
+EXPORT_SYMBOL_GPL(clear_hv_tscchange_cb);
+
+static int hv_cpu_die(unsigned int cpu)
+{
+ struct hv_reenlightenment_control re_ctrl;
+ unsigned int new_cpu;
+ unsigned long flags;
+ void **input_arg;
+ void *input_pg = NULL;
+
+ local_irq_save(flags);
+ input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
+ input_pg = *input_arg;
+ *input_arg = NULL;
+ local_irq_restore(flags);
+ free_page((unsigned long)input_pg);
+
+ if (hv_vp_assist_page && hv_vp_assist_page[cpu])
+ wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, 0);
+
+ if (hv_reenlightenment_cb == NULL)
+ return 0;
+
+ rdmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl));
+ if (re_ctrl.target_vp == hv_vp_index[cpu]) {
+ /* Reassign to some other online CPU */
+ new_cpu = cpumask_any_but(cpu_online_mask, cpu);
+
+ re_ctrl.target_vp = hv_vp_index[new_cpu];
+ wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl));
+ }
+
+ return 0;
+}
+
+/*
+ * This function is to be invoked early in the boot sequence after the
+ * hypervisor has been detected.
+ *
+ * 1. Setup the hypercall page.
+ * 2. Register Hyper-V specific clocksource.
+ * 3. Setup Hyper-V specific APIC entry points.
+ */
+void __init hyperv_init(void)
+{
+ u64 guest_id, required_msrs;
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+ int cpuhp, i;
+
+ if (x86_hyper_type != X86_HYPER_MS_HYPERV)
+ return;
+
+ /* Absolutely required MSRs */
+ required_msrs = HV_X64_MSR_HYPERCALL_AVAILABLE |
+ HV_X64_MSR_VP_INDEX_AVAILABLE;
+
+ if ((ms_hyperv.features & required_msrs) != required_msrs)
+ return;
+
+ /*
+ * Allocate the per-CPU state for the hypercall input arg.
+ * If this allocation fails, we will not be able to setup
+ * (per-CPU) hypercall input page and thus this failure is
+ * fatal on Hyper-V.
+ */
+ hyperv_pcpu_input_arg = alloc_percpu(void *);
+
+ BUG_ON(hyperv_pcpu_input_arg == NULL);
+
+ /* Allocate percpu VP index */
+ hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index),
+ GFP_KERNEL);
+ if (!hv_vp_index)
+ return;
+
+ for (i = 0; i < num_possible_cpus(); i++)
+ hv_vp_index[i] = VP_INVAL;
+
+ hv_vp_assist_page = kcalloc(num_possible_cpus(),
+ sizeof(*hv_vp_assist_page), GFP_KERNEL);
+ if (!hv_vp_assist_page) {
+ ms_hyperv.hints &= ~HV_X64_ENLIGHTENED_VMCS_RECOMMENDED;
+ goto free_vp_index;
+ }
+
+ cpuhp = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/hyperv_init:online",
+ hv_cpu_init, hv_cpu_die);
+ if (cpuhp < 0)
+ goto free_vp_assist_page;
+
+ /*
+ * Setup the hypercall page and enable hypercalls.
+ * 1. Register the guest ID
+ * 2. Enable the hypercall and register the hypercall page
+ */
+ guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
+
+ hv_hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX);
+ if (hv_hypercall_pg == NULL) {
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
+ goto remove_cpuhp_state;
+ }
+
+ rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ hypercall_msr.enable = 1;
+ hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ hv_apic_init();
+
+ /*
+ * Register Hyper-V specific clocksource.
+ */
+#ifdef CONFIG_HYPERV_TSCPAGE
+ if (ms_hyperv.features & HV_MSR_REFERENCE_TSC_AVAILABLE) {
+ union hv_x64_msr_hypercall_contents tsc_msr;
+
+ tsc_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL);
+ if (!tsc_pg)
+ goto register_msr_cs;
+
+ hyperv_cs = &hyperv_cs_tsc;
+
+ rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64);
+
+ tsc_msr.enable = 1;
+ tsc_msr.guest_physical_address = vmalloc_to_pfn(tsc_pg);
+
+ wrmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64);
+
+ hyperv_cs_tsc.archdata.vclock_mode = VCLOCK_HVCLOCK;
+
+ clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
+ return;
+ }
+register_msr_cs:
+#endif
+ /*
+ * For 32 bit guests just use the MSR based mechanism for reading
+ * the partition counter.
+ */
+
+ hyperv_cs = &hyperv_cs_msr;
+ if (ms_hyperv.features & HV_MSR_TIME_REF_COUNT_AVAILABLE)
+ clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100);
+
+ return;
+
+remove_cpuhp_state:
+ cpuhp_remove_state(cpuhp);
+free_vp_assist_page:
+ kfree(hv_vp_assist_page);
+ hv_vp_assist_page = NULL;
+free_vp_index:
+ kfree(hv_vp_index);
+ hv_vp_index = NULL;
+}
+
+/*
+ * This routine is called before kexec/kdump, it does the required cleanup.
+ */
+void hyperv_cleanup(void)
+{
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+
+ /* Reset our OS id */
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
+
+ /* Reset the hypercall page */
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ /* Reset the TSC page */
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_REFERENCE_TSC, hypercall_msr.as_uint64);
+}
+EXPORT_SYMBOL_GPL(hyperv_cleanup);
+
+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;
+
+ rdmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
+
+ wrmsrl(HV_X64_MSR_CRASH_P0, err);
+ wrmsrl(HV_X64_MSR_CRASH_P1, guest_id);
+ wrmsrl(HV_X64_MSR_CRASH_P2, regs->ip);
+ wrmsrl(HV_X64_MSR_CRASH_P3, regs->ax);
+ wrmsrl(HV_X64_MSR_CRASH_P4, regs->sp);
+
+ /*
+ * Let Hyper-V know there is crash data available
+ */
+ wrmsrl(HV_X64_MSR_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.
+ */
+ wrmsrl(HV_X64_MSR_CRASH_P0, 0);
+ wrmsrl(HV_X64_MSR_CRASH_P1, 0);
+ wrmsrl(HV_X64_MSR_CRASH_P2, 0);
+ wrmsrl(HV_X64_MSR_CRASH_P3, pa);
+ wrmsrl(HV_X64_MSR_CRASH_P4, size);
+
+ /*
+ * Let Hyper-V know there is crash data available along with
+ * the panic message.
+ */
+ wrmsrl(HV_X64_MSR_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)
+{
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+
+ /*
+ * Ensure that we're really on Hyper-V, and not a KVM or Xen
+ * emulation of Hyper-V
+ */
+ if (x86_hyper_type != X86_HYPER_MS_HYPERV)
+ return false;
+
+ /*
+ * Verify that earlier initialization succeeded by checking
+ * that the hypercall page is setup
+ */
+ hypercall_msr.as_uint64 = 0;
+ rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ return hypercall_msr.enable;
+}
+EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized);
diff --git a/arch/x86/hyperv/mmu.c b/arch/x86/hyperv/mmu.c
new file mode 100644
index 0000000..ef5f29f
--- /dev/null
+++ b/arch/x86/hyperv/mmu.c
@@ -0,0 +1,236 @@
+#define pr_fmt(fmt) "Hyper-V: " fmt
+
+#include <linux/hyperv.h>
+#include <linux/log2.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <asm/fpu/api.h>
+#include <asm/mshyperv.h>
+#include <asm/msr.h>
+#include <asm/tlbflush.h>
+#include <asm/tlb.h>
+
+#define CREATE_TRACE_POINTS
+#include <asm/trace/hyperv.h>
+
+/* Each gva in gva_list encodes up to 4096 pages to flush */
+#define HV_TLB_FLUSH_UNIT (4096 * PAGE_SIZE)
+
+static u64 hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
+ const struct flush_tlb_info *info);
+
+/*
+ * Fills in gva_list starting from offset. Returns the number of items added.
+ */
+static inline int fill_gva_list(u64 gva_list[], int offset,
+ unsigned long start, unsigned long end)
+{
+ int gva_n = offset;
+ unsigned long cur = start, diff;
+
+ do {
+ diff = end > cur ? end - cur : 0;
+
+ gva_list[gva_n] = cur & PAGE_MASK;
+ /*
+ * Lower 12 bits encode the number of additional
+ * pages to flush (in addition to the 'cur' page).
+ */
+ if (diff >= HV_TLB_FLUSH_UNIT)
+ gva_list[gva_n] |= ~PAGE_MASK;
+ else if (diff)
+ gva_list[gva_n] |= (diff - 1) >> PAGE_SHIFT;
+
+ cur += HV_TLB_FLUSH_UNIT;
+ gva_n++;
+
+ } while (cur < end);
+
+ return gva_n - offset;
+}
+
+static void hyperv_flush_tlb_others(const struct cpumask *cpus,
+ const struct flush_tlb_info *info)
+{
+ int cpu, vcpu, gva_n, max_gvas;
+ struct hv_tlb_flush **flush_pcpu;
+ struct hv_tlb_flush *flush;
+ u64 status = U64_MAX;
+ unsigned long flags;
+
+ trace_hyperv_mmu_flush_tlb_others(cpus, info);
+
+ if (!hv_hypercall_pg)
+ goto do_native;
+
+ if (cpumask_empty(cpus))
+ return;
+
+ local_irq_save(flags);
+
+ flush_pcpu = (struct hv_tlb_flush **)
+ this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ flush = *flush_pcpu;
+
+ if (unlikely(!flush)) {
+ local_irq_restore(flags);
+ goto do_native;
+ }
+
+ if (info->mm) {
+ /*
+ * AddressSpace argument must match the CR3 with PCID bits
+ * stripped out.
+ */
+ flush->address_space = virt_to_phys(info->mm->pgd);
+ flush->address_space &= CR3_ADDR_MASK;
+ flush->flags = 0;
+ } else {
+ flush->address_space = 0;
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ }
+
+ flush->processor_mask = 0;
+ if (cpumask_equal(cpus, cpu_present_mask)) {
+ flush->flags |= HV_FLUSH_ALL_PROCESSORS;
+ } else {
+ /*
+ * From the supplied CPU set we need to figure out if we can get
+ * away with cheaper HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}
+ * hypercalls. This is possible when the highest VP number in
+ * the set is < 64. As VP numbers are usually in ascending order
+ * and match Linux CPU ids, here is an optimization: we check
+ * the VP number for the highest bit in the supplied set first
+ * so we can quickly find out if using *_EX hypercalls is a
+ * must. We will also check all VP numbers when walking the
+ * supplied CPU set to remain correct in all cases.
+ */
+ if (hv_cpu_number_to_vp_number(cpumask_last(cpus)) >= 64)
+ goto do_ex_hypercall;
+
+ for_each_cpu(cpu, cpus) {
+ vcpu = hv_cpu_number_to_vp_number(cpu);
+ if (vcpu == VP_INVAL) {
+ local_irq_restore(flags);
+ goto do_native;
+ }
+
+ if (vcpu >= 64)
+ goto do_ex_hypercall;
+
+ __set_bit(vcpu, (unsigned long *)
+ &flush->processor_mask);
+ }
+ }
+
+ /*
+ * We can flush not more than max_gvas with one hypercall. Flush the
+ * whole address space if we were asked to do more.
+ */
+ max_gvas = (PAGE_SIZE - sizeof(*flush)) / sizeof(flush->gva_list[0]);
+
+ if (info->end == TLB_FLUSH_ALL) {
+ flush->flags |= HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY;
+ status = hv_do_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE,
+ flush, NULL);
+ } else if (info->end &&
+ ((info->end - info->start)/HV_TLB_FLUSH_UNIT) > max_gvas) {
+ status = hv_do_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE,
+ flush, NULL);
+ } else {
+ gva_n = fill_gva_list(flush->gva_list, 0,
+ info->start, info->end);
+ status = hv_do_rep_hypercall(HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST,
+ gva_n, 0, flush, NULL);
+ }
+ goto check_status;
+
+do_ex_hypercall:
+ status = hyperv_flush_tlb_others_ex(cpus, info);
+
+check_status:
+ local_irq_restore(flags);
+
+ if (!(status & HV_HYPERCALL_RESULT_MASK))
+ return;
+do_native:
+ native_flush_tlb_others(cpus, info);
+}
+
+static u64 hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
+ const struct flush_tlb_info *info)
+{
+ int nr_bank = 0, max_gvas, gva_n;
+ struct hv_tlb_flush_ex **flush_pcpu;
+ struct hv_tlb_flush_ex *flush;
+ u64 status;
+
+ if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
+ return U64_MAX;
+
+ flush_pcpu = (struct hv_tlb_flush_ex **)
+ this_cpu_ptr(hyperv_pcpu_input_arg);
+
+ flush = *flush_pcpu;
+
+ if (info->mm) {
+ /*
+ * AddressSpace argument must match the CR3 with PCID bits
+ * stripped out.
+ */
+ flush->address_space = virt_to_phys(info->mm->pgd);
+ flush->address_space &= CR3_ADDR_MASK;
+ flush->flags = 0;
+ } else {
+ flush->address_space = 0;
+ flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
+ }
+
+ flush->hv_vp_set.valid_bank_mask = 0;
+
+ flush->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
+ nr_bank = cpumask_to_vpset(&(flush->hv_vp_set), cpus);
+ if (nr_bank < 0)
+ return U64_MAX;
+
+ /*
+ * We can flush not more than max_gvas with one hypercall. Flush the
+ * whole address space if we were asked to do more.
+ */
+ max_gvas =
+ (PAGE_SIZE - sizeof(*flush) - nr_bank *
+ sizeof(flush->hv_vp_set.bank_contents[0])) /
+ sizeof(flush->gva_list[0]);
+
+ if (info->end == TLB_FLUSH_ALL) {
+ flush->flags |= HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY;
+ status = hv_do_rep_hypercall(
+ HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX,
+ 0, nr_bank, flush, NULL);
+ } else if (info->end &&
+ ((info->end - info->start)/HV_TLB_FLUSH_UNIT) > max_gvas) {
+ status = hv_do_rep_hypercall(
+ HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX,
+ 0, nr_bank, flush, NULL);
+ } else {
+ gva_n = fill_gva_list(flush->gva_list, nr_bank,
+ info->start, info->end);
+ status = hv_do_rep_hypercall(
+ HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX,
+ gva_n, nr_bank, flush, NULL);
+ }
+
+ return status;
+}
+
+void hyperv_setup_mmu_ops(void)
+{
+ if (!(ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED))
+ return;
+
+ pr_info("Using hypercall for remote TLB flush\n");
+ pv_mmu_ops.flush_tlb_others = hyperv_flush_tlb_others;
+ pv_mmu_ops.tlb_remove_table = tlb_remove_table;
+}
diff --git a/arch/x86/hyperv/nested.c b/arch/x86/hyperv/nested.c
new file mode 100644
index 0000000..b8e60cc
--- /dev/null
+++ b/arch/x86/hyperv/nested.c
@@ -0,0 +1,56 @@
+// 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>
+
+#include <asm/trace/hyperv.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:
+ trace_hyperv_nested_flush_guest_mapping(as, ret);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(hyperv_flush_guest_mapping);