blob: 23774970c9df66fb771210df9374bf10c0abbffa [file] [log] [blame]
/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <linux/bug.h>
#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/mman.h>
#include <linux/sched.h>
#include <linux/kvm.h>
#include <linux/kvm_irqfd.h>
#include <linux/irqbypass.h>
#include <linux/sched/stat.h>
#include <trace/events/kvm.h>
#include <kvm/arm_pmu.h>
#include <kvm/arm_psci.h>
#define CREATE_TRACE_POINTS
#include "trace.h"
#include <linux/uaccess.h>
#include <asm/ptrace.h>
#include <asm/mman.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
#include <asm/virt.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_coproc.h>
#include <asm/sections.h>
#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
#endif
DEFINE_PER_CPU(kvm_cpu_context_t, kvm_host_cpu_state);
static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
/* Per-CPU variable containing the currently running vcpu. */
static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
/* The VMID used in the VTTBR */
static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
static u32 kvm_next_vmid;
static unsigned int kvm_vmid_bits __read_mostly;
static DEFINE_RWLOCK(kvm_vmid_lock);
static bool vgic_present;
static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
{
__this_cpu_write(kvm_arm_running_vcpu, vcpu);
}
DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
/**
* kvm_arm_get_running_vcpu - get the vcpu running on the current CPU.
* Must be called from non-preemptible context
*/
struct kvm_vcpu *kvm_arm_get_running_vcpu(void)
{
return __this_cpu_read(kvm_arm_running_vcpu);
}
/**
* kvm_arm_get_running_vcpus - get the per-CPU array of currently running vcpus.
*/
struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
{
return &kvm_arm_running_vcpu;
}
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
{
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}
int kvm_arch_hardware_setup(void)
{
return 0;
}
void kvm_arch_check_processor_compat(void *rtn)
{
*(int *)rtn = 0;
}
/**
* kvm_arch_init_vm - initializes a VM data structure
* @kvm: pointer to the KVM struct
*/
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
int ret, cpu;
ret = kvm_arm_setup_stage2(kvm, type);
if (ret)
return ret;
kvm->arch.last_vcpu_ran = alloc_percpu(typeof(*kvm->arch.last_vcpu_ran));
if (!kvm->arch.last_vcpu_ran)
return -ENOMEM;
for_each_possible_cpu(cpu)
*per_cpu_ptr(kvm->arch.last_vcpu_ran, cpu) = -1;
ret = kvm_alloc_stage2_pgd(kvm);
if (ret)
goto out_fail_alloc;
ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP);
if (ret)
goto out_free_stage2_pgd;
kvm_vgic_early_init(kvm);
/* Mark the initial VMID generation invalid */
kvm->arch.vmid_gen = 0;
/* The maximum number of VCPUs is limited by the host's GIC model */
kvm->arch.max_vcpus = vgic_present ?
kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
return ret;
out_free_stage2_pgd:
kvm_free_stage2_pgd(kvm);
out_fail_alloc:
free_percpu(kvm->arch.last_vcpu_ran);
kvm->arch.last_vcpu_ran = NULL;
return ret;
}
bool kvm_arch_has_vcpu_debugfs(void)
{
return false;
}
int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
{
return 0;
}
vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
}
/**
* kvm_arch_destroy_vm - destroy the VM data structure
* @kvm: pointer to the KVM struct
*/
void kvm_arch_destroy_vm(struct kvm *kvm)
{
int i;
kvm_vgic_destroy(kvm);
free_percpu(kvm->arch.last_vcpu_ran);
kvm->arch.last_vcpu_ran = NULL;
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (kvm->vcpus[i]) {
kvm_arch_vcpu_free(kvm->vcpus[i]);
kvm->vcpus[i] = NULL;
}
}
atomic_set(&kvm->online_vcpus, 0);
}
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
switch (ext) {
case KVM_CAP_IRQCHIP:
r = vgic_present;
break;
case KVM_CAP_IOEVENTFD:
case KVM_CAP_DEVICE_CTRL:
case KVM_CAP_USER_MEMORY:
case KVM_CAP_SYNC_MMU:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_ONE_REG:
case KVM_CAP_ARM_PSCI:
case KVM_CAP_ARM_PSCI_0_2:
case KVM_CAP_READONLY_MEM:
case KVM_CAP_MP_STATE:
case KVM_CAP_IMMEDIATE_EXIT:
case KVM_CAP_VCPU_EVENTS:
r = 1;
break;
case KVM_CAP_ARM_SET_DEVICE_ADDR:
r = 1;
break;
case KVM_CAP_NR_VCPUS:
r = num_online_cpus();
break;
case KVM_CAP_MAX_VCPUS:
r = KVM_MAX_VCPUS;
break;
case KVM_CAP_NR_MEMSLOTS:
r = KVM_USER_MEM_SLOTS;
break;
case KVM_CAP_MSI_DEVID:
if (!kvm)
r = -EINVAL;
else
r = kvm->arch.vgic.msis_require_devid;
break;
case KVM_CAP_ARM_USER_IRQ:
/*
* 1: EL1_VTIMER, EL1_PTIMER, and PMU.
* (bump this number if adding more devices)
*/
r = 1;
break;
default:
r = kvm_arch_vm_ioctl_check_extension(kvm, ext);
break;
}
return r;
}
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
return -EINVAL;
}
struct kvm *kvm_arch_alloc_vm(void)
{
if (!has_vhe())
return kzalloc(sizeof(struct kvm), GFP_KERNEL);
return vzalloc(sizeof(struct kvm));
}
void kvm_arch_free_vm(struct kvm *kvm)
{
if (!has_vhe())
kfree(kvm);
else
vfree(kvm);
}
struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
{
int err;
struct kvm_vcpu *vcpu;
if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) {
err = -EBUSY;
goto out;
}
if (id >= kvm->arch.max_vcpus) {
err = -EINVAL;
goto out;
}
vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
if (!vcpu) {
err = -ENOMEM;
goto out;
}
err = kvm_vcpu_init(vcpu, kvm, id);
if (err)
goto free_vcpu;
err = create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
if (err)
goto vcpu_uninit;
return vcpu;
vcpu_uninit:
kvm_vcpu_uninit(vcpu);
free_vcpu:
kmem_cache_free(kvm_vcpu_cache, vcpu);
out:
return ERR_PTR(err);
}
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
}
void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
{
if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm)))
static_branch_dec(&userspace_irqchip_in_use);
kvm_mmu_free_memory_caches(vcpu);
kvm_timer_vcpu_terminate(vcpu);
kvm_pmu_vcpu_destroy(vcpu);
kvm_vcpu_uninit(vcpu);
kmem_cache_free(kvm_vcpu_cache, vcpu);
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
kvm_arch_vcpu_free(vcpu);
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
return kvm_timer_is_pending(vcpu);
}
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
kvm_timer_schedule(vcpu);
kvm_vgic_v4_enable_doorbell(vcpu);
}
void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
kvm_timer_unschedule(vcpu);
kvm_vgic_v4_disable_doorbell(vcpu);
}
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
/* Force users to call KVM_ARM_VCPU_INIT */
vcpu->arch.target = -1;
bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
/* Set up the timer */
kvm_timer_vcpu_init(vcpu);
kvm_arm_reset_debug_ptr(vcpu);
return kvm_vgic_vcpu_init(vcpu);
}
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
int *last_ran;
last_ran = this_cpu_ptr(vcpu->kvm->arch.last_vcpu_ran);
/*
* We might get preempted before the vCPU actually runs, but
* over-invalidation doesn't affect correctness.
*/
if (*last_ran != vcpu->vcpu_id) {
kvm_call_hyp(__kvm_tlb_flush_local_vmid, vcpu);
*last_ran = vcpu->vcpu_id;
}
vcpu->cpu = cpu;
vcpu->arch.host_cpu_context = this_cpu_ptr(&kvm_host_cpu_state);
kvm_arm_set_running_vcpu(vcpu);
kvm_vgic_load(vcpu);
kvm_timer_vcpu_load(vcpu);
kvm_vcpu_load_sysregs(vcpu);
kvm_arch_vcpu_load_fp(vcpu);
if (single_task_running())
vcpu_clear_wfe_traps(vcpu);
else
vcpu_set_wfe_traps(vcpu);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_arch_vcpu_put_fp(vcpu);
kvm_vcpu_put_sysregs(vcpu);
kvm_timer_vcpu_put(vcpu);
kvm_vgic_put(vcpu);
vcpu->cpu = -1;
kvm_arm_set_running_vcpu(NULL);
}
static void vcpu_power_off(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = true;
kvm_make_request(KVM_REQ_SLEEP, vcpu);
kvm_vcpu_kick(vcpu);
}
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
if (vcpu->arch.power_off)
mp_state->mp_state = KVM_MP_STATE_STOPPED;
else
mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
return 0;
}
int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
int ret = 0;
switch (mp_state->mp_state) {
case KVM_MP_STATE_RUNNABLE:
vcpu->arch.power_off = false;
break;
case KVM_MP_STATE_STOPPED:
vcpu_power_off(vcpu);
break;
default:
ret = -EINVAL;
}
return ret;
}
/**
* kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
* @v: The VCPU pointer
*
* If the guest CPU is not waiting for interrupts or an interrupt line is
* asserted, the CPU is by definition runnable.
*/
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
&& !v->arch.power_off && !v->arch.pause);
}
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
return vcpu_mode_priv(vcpu);
}
/* Just ensure a guest exit from a particular CPU */
static void exit_vm_noop(void *info)
{
}
void force_vm_exit(const cpumask_t *mask)
{
preempt_disable();
smp_call_function_many(mask, exit_vm_noop, NULL, true);
preempt_enable();
}
/**
* need_new_vmid_gen - check that the VMID is still valid
* @kvm: The VM's VMID to check
*
* return true if there is a new generation of VMIDs being used
*
* The hardware supports only 256 values with the value zero reserved for the
* host, so we check if an assigned value belongs to a previous generation,
* which which requires us to assign a new value. If we're the first to use a
* VMID for the new generation, we must flush necessary caches and TLBs on all
* CPUs.
*/
static bool need_new_vmid_gen(struct kvm *kvm)
{
return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen));
}
/**
* update_vttbr - Update the VTTBR with a valid VMID before the guest runs
* @kvm The guest that we are about to run
*
* Called from kvm_arch_vcpu_ioctl_run before entering the guest to ensure the
* VM has a valid VMID, otherwise assigns a new one and flushes corresponding
* caches and TLBs.
*/
static void update_vttbr(struct kvm *kvm)
{
phys_addr_t pgd_phys;
u64 vmid, cnp = kvm_cpu_has_cnp() ? VTTBR_CNP_BIT : 0;
bool new_gen;
read_lock(&kvm_vmid_lock);
new_gen = need_new_vmid_gen(kvm);
read_unlock(&kvm_vmid_lock);
if (!new_gen)
return;
write_lock(&kvm_vmid_lock);
/*
* We need to re-check the vmid_gen here to ensure that if another vcpu
* already allocated a valid vmid for this vm, then this vcpu should
* use the same vmid.
*/
if (!need_new_vmid_gen(kvm)) {
write_unlock(&kvm_vmid_lock);
return;
}
/* First user of a new VMID generation? */
if (unlikely(kvm_next_vmid == 0)) {
atomic64_inc(&kvm_vmid_gen);
kvm_next_vmid = 1;
/*
* On SMP we know no other CPUs can use this CPU's or each
* other's VMID after force_vm_exit returns since the
* kvm_vmid_lock blocks them from reentry to the guest.
*/
force_vm_exit(cpu_all_mask);
/*
* Now broadcast TLB + ICACHE invalidation over the inner
* shareable domain to make sure all data structures are
* clean.
*/
kvm_call_hyp(__kvm_flush_vm_context);
}
kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen);
kvm->arch.vmid = kvm_next_vmid;
kvm_next_vmid++;
kvm_next_vmid &= (1 << kvm_vmid_bits) - 1;
/* update vttbr to be used with the new vmid */
pgd_phys = virt_to_phys(kvm->arch.pgd);
BUG_ON(pgd_phys & ~kvm_vttbr_baddr_mask(kvm));
vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK(kvm_vmid_bits);
kvm->arch.vttbr = kvm_phys_to_vttbr(pgd_phys) | vmid | cnp;
write_unlock(&kvm_vmid_lock);
}
static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
int ret = 0;
if (likely(vcpu->arch.has_run_once))
return 0;
vcpu->arch.has_run_once = true;
if (likely(irqchip_in_kernel(kvm))) {
/*
* Map the VGIC hardware resources before running a vcpu the
* first time on this VM.
*/
if (unlikely(!vgic_ready(kvm))) {
ret = kvm_vgic_map_resources(kvm);
if (ret)
return ret;
}
} else {
/*
* Tell the rest of the code that there are userspace irqchip
* VMs in the wild.
*/
static_branch_inc(&userspace_irqchip_in_use);
}
ret = kvm_timer_enable(vcpu);
if (ret)
return ret;
ret = kvm_arm_pmu_v3_enable(vcpu);
return ret;
}
bool kvm_arch_intc_initialized(struct kvm *kvm)
{
return vgic_initialized(kvm);
}
void kvm_arm_halt_guest(struct kvm *kvm)
{
int i;
struct kvm_vcpu *vcpu;
kvm_for_each_vcpu(i, vcpu, kvm)
vcpu->arch.pause = true;
kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
}
void kvm_arm_resume_guest(struct kvm *kvm)
{
int i;
struct kvm_vcpu *vcpu;
kvm_for_each_vcpu(i, vcpu, kvm) {
vcpu->arch.pause = false;
swake_up_one(kvm_arch_vcpu_wq(vcpu));
}
}
static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
{
struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
swait_event_interruptible_exclusive(*wq, ((!vcpu->arch.power_off) &&
(!vcpu->arch.pause)));
if (vcpu->arch.power_off || vcpu->arch.pause) {
/* Awaken to handle a signal, request we sleep again later. */
kvm_make_request(KVM_REQ_SLEEP, vcpu);
}
}
static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
{
return vcpu->arch.target >= 0;
}
static void check_vcpu_requests(struct kvm_vcpu *vcpu)
{
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
vcpu_req_sleep(vcpu);
/*
* Clear IRQ_PENDING requests that were made to guarantee
* that a VCPU sees new virtual interrupts.
*/
kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
}
}
/**
* kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
* @vcpu: The VCPU pointer
* @run: The kvm_run structure pointer used for userspace state exchange
*
* This function is called through the VCPU_RUN ioctl called from user space. It
* will execute VM code in a loop until the time slice for the process is used
* or some emulation is needed from user space in which case the function will
* return with return value 0 and with the kvm_run structure filled in with the
* required data for the requested emulation.
*/
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
int ret;
if (unlikely(!kvm_vcpu_initialized(vcpu)))
return -ENOEXEC;
ret = kvm_vcpu_first_run_init(vcpu);
if (ret)
return ret;
if (run->exit_reason == KVM_EXIT_MMIO) {
ret = kvm_handle_mmio_return(vcpu, vcpu->run);
if (ret)
return ret;
if (kvm_arm_handle_step_debug(vcpu, vcpu->run))
return 0;
}
if (run->immediate_exit)
return -EINTR;
vcpu_load(vcpu);
kvm_sigset_activate(vcpu);
ret = 1;
run->exit_reason = KVM_EXIT_UNKNOWN;
while (ret > 0) {
/*
* Check conditions before entering the guest
*/
cond_resched();
update_vttbr(vcpu->kvm);
check_vcpu_requests(vcpu);
/*
* Preparing the interrupts to be injected also
* involves poking the GIC, which must be done in a
* non-preemptible context.
*/
preempt_disable();
kvm_pmu_flush_hwstate(vcpu);
local_irq_disable();
kvm_vgic_flush_hwstate(vcpu);
/*
* Exit if we have a signal pending so that we can deliver the
* signal to user space.
*/
if (signal_pending(current)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
/*
* If we're using a userspace irqchip, then check if we need
* to tell a userspace irqchip about timer or PMU level
* changes and if so, exit to userspace (the actual level
* state gets updated in kvm_timer_update_run and
* kvm_pmu_update_run below).
*/
if (static_branch_unlikely(&userspace_irqchip_in_use)) {
if (kvm_timer_should_notify_user(vcpu) ||
kvm_pmu_should_notify_user(vcpu)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
}
/*
* Ensure we set mode to IN_GUEST_MODE after we disable
* interrupts and before the final VCPU requests check.
* See the comment in kvm_vcpu_exiting_guest_mode() and
* Documentation/virtual/kvm/vcpu-requests.rst
*/
smp_store_mb(vcpu->mode, IN_GUEST_MODE);
if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) ||
kvm_request_pending(vcpu)) {
vcpu->mode = OUTSIDE_GUEST_MODE;
isb(); /* Ensure work in x_flush_hwstate is committed */
kvm_pmu_sync_hwstate(vcpu);
if (static_branch_unlikely(&userspace_irqchip_in_use))
kvm_timer_sync_hwstate(vcpu);
kvm_vgic_sync_hwstate(vcpu);
local_irq_enable();
preempt_enable();
continue;
}
kvm_arm_setup_debug(vcpu);
/**************************************************************
* Enter the guest
*/
trace_kvm_entry(*vcpu_pc(vcpu));
guest_enter_irqoff();
if (has_vhe()) {
kvm_arm_vhe_guest_enter();
ret = kvm_vcpu_run_vhe(vcpu);
kvm_arm_vhe_guest_exit();
} else {
ret = kvm_call_hyp(__kvm_vcpu_run_nvhe, vcpu);
}
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->stat.exits++;
/*
* Back from guest
*************************************************************/
kvm_arm_clear_debug(vcpu);
/*
* We must sync the PMU state before the vgic state so
* that the vgic can properly sample the updated state of the
* interrupt line.
*/
kvm_pmu_sync_hwstate(vcpu);
/*
* Sync the vgic state before syncing the timer state because
* the timer code needs to know if the virtual timer
* interrupts are active.
*/
kvm_vgic_sync_hwstate(vcpu);
/*
* Sync the timer hardware state before enabling interrupts as
* we don't want vtimer interrupts to race with syncing the
* timer virtual interrupt state.
*/
if (static_branch_unlikely(&userspace_irqchip_in_use))
kvm_timer_sync_hwstate(vcpu);
kvm_arch_vcpu_ctxsync_fp(vcpu);
/*
* We may have taken a host interrupt in HYP mode (ie
* while executing the guest). This interrupt is still
* pending, as we haven't serviced it yet!
*
* We're now back in SVC mode, with interrupts
* disabled. Enabling the interrupts now will have
* the effect of taking the interrupt again, in SVC
* mode this time.
*/
local_irq_enable();
/*
* We do local_irq_enable() before calling guest_exit() so
* that if a timer interrupt hits while running the guest we
* account that tick as being spent in the guest. We enable
* preemption after calling guest_exit() so that if we get
* preempted we make sure ticks after that is not counted as
* guest time.
*/
guest_exit();
trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
/* Exit types that need handling before we can be preempted */
handle_exit_early(vcpu, run, ret);
preempt_enable();
ret = handle_exit(vcpu, run, ret);
}
/* Tell userspace about in-kernel device output levels */
if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
kvm_timer_update_run(vcpu);
kvm_pmu_update_run(vcpu);
}
kvm_sigset_deactivate(vcpu);
vcpu_put(vcpu);
return ret;
}
static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
{
int bit_index;
bool set;
unsigned long *hcr;
if (number == KVM_ARM_IRQ_CPU_IRQ)
bit_index = __ffs(HCR_VI);
else /* KVM_ARM_IRQ_CPU_FIQ */
bit_index = __ffs(HCR_VF);
hcr = vcpu_hcr(vcpu);
if (level)
set = test_and_set_bit(bit_index, hcr);
else
set = test_and_clear_bit(bit_index, hcr);
/*
* If we didn't change anything, no need to wake up or kick other CPUs
*/
if (set == level)
return 0;
/*
* The vcpu irq_lines field was updated, wake up sleeping VCPUs and
* trigger a world-switch round on the running physical CPU to set the
* virtual IRQ/FIQ fields in the HCR appropriately.
*/
kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
kvm_vcpu_kick(vcpu);
return 0;
}
int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
bool line_status)
{
u32 irq = irq_level->irq;
unsigned int irq_type, vcpu_idx, irq_num;
int nrcpus = atomic_read(&kvm->online_vcpus);
struct kvm_vcpu *vcpu = NULL;
bool level = irq_level->level;
irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
switch (irq_type) {
case KVM_ARM_IRQ_TYPE_CPU:
if (irqchip_in_kernel(kvm))
return -ENXIO;
if (vcpu_idx >= nrcpus)
return -EINVAL;
vcpu = kvm_get_vcpu(kvm, vcpu_idx);
if (!vcpu)
return -EINVAL;
if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
return -EINVAL;
return vcpu_interrupt_line(vcpu, irq_num, level);
case KVM_ARM_IRQ_TYPE_PPI:
if (!irqchip_in_kernel(kvm))
return -ENXIO;
if (vcpu_idx >= nrcpus)
return -EINVAL;
vcpu = kvm_get_vcpu(kvm, vcpu_idx);
if (!vcpu)
return -EINVAL;
if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
return -EINVAL;
return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
case KVM_ARM_IRQ_TYPE_SPI:
if (!irqchip_in_kernel(kvm))
return -ENXIO;
if (irq_num < VGIC_NR_PRIVATE_IRQS)
return -EINVAL;
return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
}
return -EINVAL;
}
static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
const struct kvm_vcpu_init *init)
{
unsigned int i;
int phys_target = kvm_target_cpu();
if (init->target != phys_target)
return -EINVAL;
/*
* Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
* use the same target.
*/
if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
return -EINVAL;
/* -ENOENT for unknown features, -EINVAL for invalid combinations. */
for (i = 0; i < sizeof(init->features) * 8; i++) {
bool set = (init->features[i / 32] & (1 << (i % 32)));
if (set && i >= KVM_VCPU_MAX_FEATURES)
return -ENOENT;
/*
* Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
* use the same feature set.
*/
if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
test_bit(i, vcpu->arch.features) != set)
return -EINVAL;
if (set)
set_bit(i, vcpu->arch.features);
}
vcpu->arch.target = phys_target;
/* Now we know what it is, we can reset it. */
return kvm_reset_vcpu(vcpu);
}
static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
struct kvm_vcpu_init *init)
{
int ret;
ret = kvm_vcpu_set_target(vcpu, init);
if (ret)
return ret;
/*
* Ensure a rebooted VM will fault in RAM pages and detect if the
* guest MMU is turned off and flush the caches as needed.
*/
if (vcpu->arch.has_run_once)
stage2_unmap_vm(vcpu->kvm);
vcpu_reset_hcr(vcpu);
/*
* Handle the "start in power-off" case.
*/
if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
vcpu_power_off(vcpu);
else
vcpu->arch.power_off = false;
return 0;
}
static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret = -ENXIO;
switch (attr->group) {
default:
ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
break;
}
return ret;
}
static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret = -ENXIO;
switch (attr->group) {
default:
ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
break;
}
return ret;
}
static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
int ret = -ENXIO;
switch (attr->group) {
default:
ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
break;
}
return ret;
}
static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events)
{
memset(events, 0, sizeof(*events));
return __kvm_arm_vcpu_get_events(vcpu, events);
}
static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events)
{
int i;
/* check whether the reserved field is zero */
for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
if (events->reserved[i])
return -EINVAL;
/* check whether the pad field is zero */
for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
if (events->exception.pad[i])
return -EINVAL;
return __kvm_arm_vcpu_set_events(vcpu, events);
}
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
struct kvm_device_attr attr;
long r;
switch (ioctl) {
case KVM_ARM_VCPU_INIT: {
struct kvm_vcpu_init init;
r = -EFAULT;
if (copy_from_user(&init, argp, sizeof(init)))
break;
r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
break;
}
case KVM_SET_ONE_REG:
case KVM_GET_ONE_REG: {
struct kvm_one_reg reg;
r = -ENOEXEC;
if (unlikely(!kvm_vcpu_initialized(vcpu)))
break;
r = -EFAULT;
if (copy_from_user(&reg, argp, sizeof(reg)))
break;
if (ioctl == KVM_SET_ONE_REG)
r = kvm_arm_set_reg(vcpu, &reg);
else
r = kvm_arm_get_reg(vcpu, &reg);
break;
}
case KVM_GET_REG_LIST: {
struct kvm_reg_list __user *user_list = argp;
struct kvm_reg_list reg_list;
unsigned n;
r = -ENOEXEC;
if (unlikely(!kvm_vcpu_initialized(vcpu)))
break;
r = -EFAULT;
if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
break;
n = reg_list.n;
reg_list.n = kvm_arm_num_regs(vcpu);
if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
break;
r = -E2BIG;
if (n < reg_list.n)
break;
r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
break;
}
case KVM_SET_DEVICE_ATTR: {
r = -EFAULT;
if (copy_from_user(&attr, argp, sizeof(attr)))
break;
r = kvm_arm_vcpu_set_attr(vcpu, &attr);
break;
}
case KVM_GET_DEVICE_ATTR: {
r = -EFAULT;
if (copy_from_user(&attr, argp, sizeof(attr)))
break;
r = kvm_arm_vcpu_get_attr(vcpu, &attr);
break;
}
case KVM_HAS_DEVICE_ATTR: {
r = -EFAULT;
if (copy_from_user(&attr, argp, sizeof(attr)))
break;
r = kvm_arm_vcpu_has_attr(vcpu, &attr);
break;
}
case KVM_GET_VCPU_EVENTS: {
struct kvm_vcpu_events events;
if (kvm_arm_vcpu_get_events(vcpu, &events))
return -EINVAL;
if (copy_to_user(argp, &events, sizeof(events)))
return -EFAULT;
return 0;
}
case KVM_SET_VCPU_EVENTS: {
struct kvm_vcpu_events events;
if (copy_from_user(&events, argp, sizeof(events)))
return -EFAULT;
return kvm_arm_vcpu_set_events(vcpu, &events);
}
default:
r = -EINVAL;
}
return r;
}
/**
* kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
* @kvm: kvm instance
* @log: slot id and address to which we copy the log
*
* Steps 1-4 below provide general overview of dirty page logging. See
* kvm_get_dirty_log_protect() function description for additional details.
*
* We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
* always flush the TLB (step 4) even if previous step failed and the dirty
* bitmap may be corrupt. Regardless of previous outcome the KVM logging API
* does not preclude user space subsequent dirty log read. Flushing TLB ensures
* writes will be marked dirty for next log read.
*
* 1. Take a snapshot of the bit and clear it if needed.
* 2. Write protect the corresponding page.
* 3. Copy the snapshot to the userspace.
* 4. Flush TLB's if needed.
*/
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
{
bool is_dirty = false;
int r;
mutex_lock(&kvm->slots_lock);
r = kvm_get_dirty_log_protect(kvm, log, &is_dirty);
if (is_dirty)
kvm_flush_remote_tlbs(kvm);
mutex_unlock(&kvm->slots_lock);
return r;
}
static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
struct kvm_arm_device_addr *dev_addr)
{
unsigned long dev_id, type;
dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
KVM_ARM_DEVICE_ID_SHIFT;
type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
KVM_ARM_DEVICE_TYPE_SHIFT;
switch (dev_id) {
case KVM_ARM_DEVICE_VGIC_V2:
if (!vgic_present)
return -ENXIO;
return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
default:
return -ENODEV;
}
}
long kvm_arch_vm_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm *kvm = filp->private_data;
void __user *argp = (void __user *)arg;
switch (ioctl) {
case KVM_CREATE_IRQCHIP: {
int ret;
if (!vgic_present)
return -ENXIO;
mutex_lock(&kvm->lock);
ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
mutex_unlock(&kvm->lock);
return ret;
}
case KVM_ARM_SET_DEVICE_ADDR: {
struct kvm_arm_device_addr dev_addr;
if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
return -EFAULT;
return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
}
case KVM_ARM_PREFERRED_TARGET: {
int err;
struct kvm_vcpu_init init;
err = kvm_vcpu_preferred_target(&init);
if (err)
return err;
if (copy_to_user(argp, &init, sizeof(init)))
return -EFAULT;
return 0;
}
default:
return -EINVAL;
}
}
static void cpu_init_hyp_mode(void *dummy)
{
phys_addr_t pgd_ptr;
unsigned long hyp_stack_ptr;
unsigned long stack_page;
unsigned long vector_ptr;
/* Switch from the HYP stub to our own HYP init vector */
__hyp_set_vectors(kvm_get_idmap_vector());
pgd_ptr = kvm_mmu_get_httbr();
stack_page = __this_cpu_read(kvm_arm_hyp_stack_page);
hyp_stack_ptr = stack_page + PAGE_SIZE;
vector_ptr = (unsigned long)kvm_get_hyp_vector();
__cpu_init_hyp_mode(pgd_ptr, hyp_stack_ptr, vector_ptr);
__cpu_init_stage2();
}
static void cpu_hyp_reset(void)
{
if (!is_kernel_in_hyp_mode())
__hyp_reset_vectors();
}
static void cpu_hyp_reinit(void)
{
cpu_hyp_reset();
if (is_kernel_in_hyp_mode())
kvm_timer_init_vhe();
else
cpu_init_hyp_mode(NULL);
kvm_arm_init_debug();
if (vgic_present)
kvm_vgic_init_cpu_hardware();
}
static void _kvm_arch_hardware_enable(void *discard)
{
if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
cpu_hyp_reinit();
__this_cpu_write(kvm_arm_hardware_enabled, 1);
}
}
int kvm_arch_hardware_enable(void)
{
_kvm_arch_hardware_enable(NULL);
return 0;
}
static void _kvm_arch_hardware_disable(void *discard)
{
if (__this_cpu_read(kvm_arm_hardware_enabled)) {
cpu_hyp_reset();
__this_cpu_write(kvm_arm_hardware_enabled, 0);
}
}
void kvm_arch_hardware_disable(void)
{
_kvm_arch_hardware_disable(NULL);
}
#ifdef CONFIG_CPU_PM
static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
unsigned long cmd,
void *v)
{
/*
* kvm_arm_hardware_enabled is left with its old value over
* PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
* re-enable hyp.
*/
switch (cmd) {
case CPU_PM_ENTER:
if (__this_cpu_read(kvm_arm_hardware_enabled))
/*
* don't update kvm_arm_hardware_enabled here
* so that the hardware will be re-enabled
* when we resume. See below.
*/
cpu_hyp_reset();
return NOTIFY_OK;
case CPU_PM_ENTER_FAILED:
case CPU_PM_EXIT:
if (__this_cpu_read(kvm_arm_hardware_enabled))
/* The hardware was enabled before suspend. */
cpu_hyp_reinit();
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
}
static struct notifier_block hyp_init_cpu_pm_nb = {
.notifier_call = hyp_init_cpu_pm_notifier,
};
static void __init hyp_cpu_pm_init(void)
{
cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
}
static void __init hyp_cpu_pm_exit(void)
{
cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
}
#else
static inline void hyp_cpu_pm_init(void)
{
}
static inline void hyp_cpu_pm_exit(void)
{
}
#endif
static int init_common_resources(void)
{
/* set size of VMID supported by CPU */
kvm_vmid_bits = kvm_get_vmid_bits();
kvm_info("%d-bit VMID\n", kvm_vmid_bits);
kvm_set_ipa_limit();
return 0;
}
static int init_subsystems(void)
{
int err = 0;
/*
* Enable hardware so that subsystem initialisation can access EL2.
*/
on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
/*
* Register CPU lower-power notifier
*/
hyp_cpu_pm_init();
/*
* Init HYP view of VGIC
*/
err = kvm_vgic_hyp_init();
switch (err) {
case 0:
vgic_present = true;
break;
case -ENODEV:
case -ENXIO:
vgic_present = false;
err = 0;
break;
default:
goto out;
}
/*
* Init HYP architected timer support
*/
err = kvm_timer_hyp_init(vgic_present);
if (err)
goto out;
kvm_perf_init();
kvm_coproc_table_init();
out:
on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
return err;
}
static void teardown_hyp_mode(void)
{
int cpu;
free_hyp_pgds();
for_each_possible_cpu(cpu)
free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
hyp_cpu_pm_exit();
}
/**
* Inits Hyp-mode on all online CPUs
*/
static int init_hyp_mode(void)
{
int cpu;
int err = 0;
/*
* Allocate Hyp PGD and setup Hyp identity mapping
*/
err = kvm_mmu_init();
if (err)
goto out_err;
/*
* Allocate stack pages for Hypervisor-mode
*/
for_each_possible_cpu(cpu) {
unsigned long stack_page;
stack_page = __get_free_page(GFP_KERNEL);
if (!stack_page) {
err = -ENOMEM;
goto out_err;
}
per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
}
/*
* Map the Hyp-code called directly from the host
*/
err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
if (err) {
kvm_err("Cannot map world-switch code\n");
goto out_err;
}
err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
if (err) {
kvm_err("Cannot map rodata section\n");
goto out_err;
}
err = create_hyp_mappings(kvm_ksym_ref(__bss_start),
kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
if (err) {
kvm_err("Cannot map bss section\n");
goto out_err;
}
err = kvm_map_vectors();
if (err) {
kvm_err("Cannot map vectors\n");
goto out_err;
}
/*
* Map the Hyp stack pages
*/
for_each_possible_cpu(cpu) {
char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
PAGE_HYP);
if (err) {
kvm_err("Cannot map hyp stack\n");
goto out_err;
}
}
for_each_possible_cpu(cpu) {
kvm_cpu_context_t *cpu_ctxt;
cpu_ctxt = per_cpu_ptr(&kvm_host_cpu_state, cpu);
err = create_hyp_mappings(cpu_ctxt, cpu_ctxt + 1, PAGE_HYP);
if (err) {
kvm_err("Cannot map host CPU state: %d\n", err);
goto out_err;
}
}
err = hyp_map_aux_data();
if (err)
kvm_err("Cannot map host auxilary data: %d\n", err);
return 0;
out_err:
teardown_hyp_mode();
kvm_err("error initializing Hyp mode: %d\n", err);
return err;
}
static void check_kvm_target_cpu(void *ret)
{
*(int *)ret = kvm_target_cpu();
}
struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
{
struct kvm_vcpu *vcpu;
int i;
mpidr &= MPIDR_HWID_BITMASK;
kvm_for_each_vcpu(i, vcpu, kvm) {
if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
return vcpu;
}
return NULL;
}
bool kvm_arch_has_irq_bypass(void)
{
return true;
}
int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
struct irq_bypass_producer *prod)
{
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
&irqfd->irq_entry);
}
void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
struct irq_bypass_producer *prod)
{
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
&irqfd->irq_entry);
}
void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
{
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
kvm_arm_halt_guest(irqfd->kvm);
}
void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
{
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
kvm_arm_resume_guest(irqfd->kvm);
}
/**
* Initialize Hyp-mode and memory mappings on all CPUs.
*/
int kvm_arch_init(void *opaque)
{
int err;
int ret, cpu;
bool in_hyp_mode;
if (!is_hyp_mode_available()) {
kvm_info("HYP mode not available\n");
return -ENODEV;
}
if (!kvm_arch_check_sve_has_vhe()) {
kvm_pr_unimpl("SVE system without VHE unsupported. Broken cpu?");
return -ENODEV;
}
for_each_online_cpu(cpu) {
smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
if (ret < 0) {
kvm_err("Error, CPU %d not supported!\n", cpu);
return -ENODEV;
}
}
err = init_common_resources();
if (err)
return err;
in_hyp_mode = is_kernel_in_hyp_mode();
if (!in_hyp_mode) {
err = init_hyp_mode();
if (err)
goto out_err;
}
err = init_subsystems();
if (err)
goto out_hyp;
if (in_hyp_mode)
kvm_info("VHE mode initialized successfully\n");
else
kvm_info("Hyp mode initialized successfully\n");
return 0;
out_hyp:
if (!in_hyp_mode)
teardown_hyp_mode();
out_err:
return err;
}
/* NOP: Compiling as a module not supported */
void kvm_arch_exit(void)
{
kvm_perf_teardown();
}
static int arm_init(void)
{
int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
return rc;
}
module_init(arm_init);