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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
5  */
6 
7 #include <linux/bug.h>
8 #include <linux/cpu_pm.h>
9 #include <linux/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/vmalloc.h>
15 #include <linux/fs.h>
16 #include <linux/mman.h>
17 #include <linux/sched.h>
18 #include <linux/kvm.h>
19 #include <linux/kvm_irqfd.h>
20 #include <linux/irqbypass.h>
21 #include <linux/sched/stat.h>
22 #include <trace/events/kvm.h>
23 #include <kvm/arm_pmu.h>
24 #include <kvm/arm_psci.h>
25 
26 #define CREATE_TRACE_POINTS
27 #include "trace.h"
28 
29 #include <linux/uaccess.h>
30 #include <asm/ptrace.h>
31 #include <asm/mman.h>
32 #include <asm/tlbflush.h>
33 #include <asm/cacheflush.h>
34 #include <asm/cpufeature.h>
35 #include <asm/virt.h>
36 #include <asm/kvm_arm.h>
37 #include <asm/kvm_asm.h>
38 #include <asm/kvm_mmu.h>
39 #include <asm/kvm_emulate.h>
40 #include <asm/kvm_coproc.h>
41 #include <asm/sections.h>
42 
43 #ifdef REQUIRES_VIRT
44 __asm__(".arch_extension	virt");
45 #endif
46 
47 DEFINE_PER_CPU(kvm_host_data_t, kvm_host_data);
48 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
49 
50 /* Per-CPU variable containing the currently running vcpu. */
51 static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
52 
53 /* The VMID used in the VTTBR */
54 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
55 static u32 kvm_next_vmid;
56 static DEFINE_SPINLOCK(kvm_vmid_lock);
57 
58 static bool vgic_present;
59 
60 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
61 
kvm_arm_set_running_vcpu(struct kvm_vcpu * vcpu)62 static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
63 {
64 	__this_cpu_write(kvm_arm_running_vcpu, vcpu);
65 }
66 
67 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
68 
69 /**
70  * kvm_arm_get_running_vcpu - get the vcpu running on the current CPU.
71  * Must be called from non-preemptible context
72  */
kvm_arm_get_running_vcpu(void)73 struct kvm_vcpu *kvm_arm_get_running_vcpu(void)
74 {
75 	return __this_cpu_read(kvm_arm_running_vcpu);
76 }
77 
78 /**
79  * kvm_arm_get_running_vcpus - get the per-CPU array of currently running vcpus.
80  */
kvm_get_running_vcpus(void)81 struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
82 {
83 	return &kvm_arm_running_vcpu;
84 }
85 
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)86 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
87 {
88 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
89 }
90 
kvm_arch_hardware_setup(void)91 int kvm_arch_hardware_setup(void)
92 {
93 	return 0;
94 }
95 
kvm_arch_check_processor_compat(void)96 int kvm_arch_check_processor_compat(void)
97 {
98 	return 0;
99 }
100 
101 
102 /**
103  * kvm_arch_init_vm - initializes a VM data structure
104  * @kvm:	pointer to the KVM struct
105  */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)106 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
107 {
108 	int ret, cpu;
109 
110 	ret = kvm_arm_setup_stage2(kvm, type);
111 	if (ret)
112 		return ret;
113 
114 	kvm->arch.last_vcpu_ran = alloc_percpu(typeof(*kvm->arch.last_vcpu_ran));
115 	if (!kvm->arch.last_vcpu_ran)
116 		return -ENOMEM;
117 
118 	for_each_possible_cpu(cpu)
119 		*per_cpu_ptr(kvm->arch.last_vcpu_ran, cpu) = -1;
120 
121 	ret = kvm_alloc_stage2_pgd(kvm);
122 	if (ret)
123 		goto out_fail_alloc;
124 
125 	ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP);
126 	if (ret)
127 		goto out_free_stage2_pgd;
128 
129 	kvm_vgic_early_init(kvm);
130 
131 	/* Mark the initial VMID generation invalid */
132 	kvm->arch.vmid.vmid_gen = 0;
133 
134 	/* The maximum number of VCPUs is limited by the host's GIC model */
135 	kvm->arch.max_vcpus = vgic_present ?
136 				kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
137 
138 	return ret;
139 out_free_stage2_pgd:
140 	kvm_free_stage2_pgd(kvm);
141 out_fail_alloc:
142 	free_percpu(kvm->arch.last_vcpu_ran);
143 	kvm->arch.last_vcpu_ran = NULL;
144 	return ret;
145 }
146 
kvm_arch_create_vcpu_debugfs(struct kvm_vcpu * vcpu)147 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
148 {
149 	return 0;
150 }
151 
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)152 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
153 {
154 	return VM_FAULT_SIGBUS;
155 }
156 
157 
158 /**
159  * kvm_arch_destroy_vm - destroy the VM data structure
160  * @kvm:	pointer to the KVM struct
161  */
kvm_arch_destroy_vm(struct kvm * kvm)162 void kvm_arch_destroy_vm(struct kvm *kvm)
163 {
164 	int i;
165 
166 	kvm_vgic_destroy(kvm);
167 
168 	free_percpu(kvm->arch.last_vcpu_ran);
169 	kvm->arch.last_vcpu_ran = NULL;
170 
171 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
172 		if (kvm->vcpus[i]) {
173 			kvm_arch_vcpu_free(kvm->vcpus[i]);
174 			kvm->vcpus[i] = NULL;
175 		}
176 	}
177 	atomic_set(&kvm->online_vcpus, 0);
178 }
179 
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)180 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
181 {
182 	int r;
183 	switch (ext) {
184 	case KVM_CAP_IRQCHIP:
185 		r = vgic_present;
186 		break;
187 	case KVM_CAP_IOEVENTFD:
188 	case KVM_CAP_DEVICE_CTRL:
189 	case KVM_CAP_USER_MEMORY:
190 	case KVM_CAP_SYNC_MMU:
191 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
192 	case KVM_CAP_ONE_REG:
193 	case KVM_CAP_ARM_PSCI:
194 	case KVM_CAP_ARM_PSCI_0_2:
195 	case KVM_CAP_READONLY_MEM:
196 	case KVM_CAP_MP_STATE:
197 	case KVM_CAP_IMMEDIATE_EXIT:
198 	case KVM_CAP_VCPU_EVENTS:
199 	case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
200 		r = 1;
201 		break;
202 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
203 		r = 1;
204 		break;
205 	case KVM_CAP_NR_VCPUS:
206 		r = num_online_cpus();
207 		break;
208 	case KVM_CAP_MAX_VCPUS:
209 		r = KVM_MAX_VCPUS;
210 		break;
211 	case KVM_CAP_MAX_VCPU_ID:
212 		r = KVM_MAX_VCPU_ID;
213 		break;
214 	case KVM_CAP_MSI_DEVID:
215 		if (!kvm)
216 			r = -EINVAL;
217 		else
218 			r = kvm->arch.vgic.msis_require_devid;
219 		break;
220 	case KVM_CAP_ARM_USER_IRQ:
221 		/*
222 		 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
223 		 * (bump this number if adding more devices)
224 		 */
225 		r = 1;
226 		break;
227 	default:
228 		r = kvm_arch_vm_ioctl_check_extension(kvm, ext);
229 		break;
230 	}
231 	return r;
232 }
233 
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)234 long kvm_arch_dev_ioctl(struct file *filp,
235 			unsigned int ioctl, unsigned long arg)
236 {
237 	return -EINVAL;
238 }
239 
kvm_arch_alloc_vm(void)240 struct kvm *kvm_arch_alloc_vm(void)
241 {
242 	if (!has_vhe())
243 		return kzalloc(sizeof(struct kvm), GFP_KERNEL);
244 
245 	return vzalloc(sizeof(struct kvm));
246 }
247 
kvm_arch_free_vm(struct kvm * kvm)248 void kvm_arch_free_vm(struct kvm *kvm)
249 {
250 	if (!has_vhe())
251 		kfree(kvm);
252 	else
253 		vfree(kvm);
254 }
255 
kvm_arch_vcpu_create(struct kvm * kvm,unsigned int id)256 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
257 {
258 	int err;
259 	struct kvm_vcpu *vcpu;
260 
261 	if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) {
262 		err = -EBUSY;
263 		goto out;
264 	}
265 
266 	if (id >= kvm->arch.max_vcpus) {
267 		err = -EINVAL;
268 		goto out;
269 	}
270 
271 	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
272 	if (!vcpu) {
273 		err = -ENOMEM;
274 		goto out;
275 	}
276 
277 	err = kvm_vcpu_init(vcpu, kvm, id);
278 	if (err)
279 		goto free_vcpu;
280 
281 	err = create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
282 	if (err)
283 		goto vcpu_uninit;
284 
285 	return vcpu;
286 vcpu_uninit:
287 	kvm_vcpu_uninit(vcpu);
288 free_vcpu:
289 	kmem_cache_free(kvm_vcpu_cache, vcpu);
290 out:
291 	return ERR_PTR(err);
292 }
293 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)294 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
295 {
296 }
297 
kvm_arch_vcpu_free(struct kvm_vcpu * vcpu)298 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
299 {
300 	if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm)))
301 		static_branch_dec(&userspace_irqchip_in_use);
302 
303 	kvm_mmu_free_memory_caches(vcpu);
304 	kvm_timer_vcpu_terminate(vcpu);
305 	kvm_pmu_vcpu_destroy(vcpu);
306 	kvm_vcpu_uninit(vcpu);
307 	kmem_cache_free(kvm_vcpu_cache, vcpu);
308 }
309 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)310 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
311 {
312 	kvm_arch_vcpu_free(vcpu);
313 }
314 
kvm_cpu_has_pending_timer(struct kvm_vcpu * vcpu)315 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
316 {
317 	return kvm_timer_is_pending(vcpu);
318 }
319 
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)320 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
321 {
322 	/*
323 	 * If we're about to block (most likely because we've just hit a
324 	 * WFI), we need to sync back the state of the GIC CPU interface
325 	 * so that we have the lastest PMR and group enables. This ensures
326 	 * that kvm_arch_vcpu_runnable has up-to-date data to decide
327 	 * whether we have pending interrupts.
328 	 */
329 	preempt_disable();
330 	kvm_vgic_vmcr_sync(vcpu);
331 	preempt_enable();
332 
333 	kvm_vgic_v4_enable_doorbell(vcpu);
334 }
335 
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)336 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
337 {
338 	kvm_vgic_v4_disable_doorbell(vcpu);
339 }
340 
kvm_arch_vcpu_init(struct kvm_vcpu * vcpu)341 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
342 {
343 	/* Force users to call KVM_ARM_VCPU_INIT */
344 	vcpu->arch.target = -1;
345 	bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
346 
347 	/* Set up the timer */
348 	kvm_timer_vcpu_init(vcpu);
349 
350 	kvm_pmu_vcpu_init(vcpu);
351 
352 	kvm_arm_reset_debug_ptr(vcpu);
353 
354 	return kvm_vgic_vcpu_init(vcpu);
355 }
356 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)357 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
358 {
359 	int *last_ran;
360 	kvm_host_data_t *cpu_data;
361 
362 	last_ran = this_cpu_ptr(vcpu->kvm->arch.last_vcpu_ran);
363 	cpu_data = this_cpu_ptr(&kvm_host_data);
364 
365 	/*
366 	 * We might get preempted before the vCPU actually runs, but
367 	 * over-invalidation doesn't affect correctness.
368 	 */
369 	if (*last_ran != vcpu->vcpu_id) {
370 		kvm_call_hyp(__kvm_tlb_flush_local_vmid, vcpu);
371 		*last_ran = vcpu->vcpu_id;
372 	}
373 
374 	vcpu->cpu = cpu;
375 	vcpu->arch.host_cpu_context = &cpu_data->host_ctxt;
376 
377 	kvm_arm_set_running_vcpu(vcpu);
378 	kvm_vgic_load(vcpu);
379 	kvm_timer_vcpu_load(vcpu);
380 	kvm_vcpu_load_sysregs(vcpu);
381 	kvm_arch_vcpu_load_fp(vcpu);
382 	kvm_vcpu_pmu_restore_guest(vcpu);
383 
384 	if (single_task_running())
385 		vcpu_clear_wfe_traps(vcpu);
386 	else
387 		vcpu_set_wfe_traps(vcpu);
388 
389 	vcpu_ptrauth_setup_lazy(vcpu);
390 }
391 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)392 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
393 {
394 	kvm_arch_vcpu_put_fp(vcpu);
395 	kvm_vcpu_put_sysregs(vcpu);
396 	kvm_timer_vcpu_put(vcpu);
397 	kvm_vgic_put(vcpu);
398 	kvm_vcpu_pmu_restore_host(vcpu);
399 
400 	vcpu->cpu = -1;
401 
402 	kvm_arm_set_running_vcpu(NULL);
403 }
404 
vcpu_power_off(struct kvm_vcpu * vcpu)405 static void vcpu_power_off(struct kvm_vcpu *vcpu)
406 {
407 	vcpu->arch.power_off = true;
408 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
409 	kvm_vcpu_kick(vcpu);
410 }
411 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)412 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
413 				    struct kvm_mp_state *mp_state)
414 {
415 	if (vcpu->arch.power_off)
416 		mp_state->mp_state = KVM_MP_STATE_STOPPED;
417 	else
418 		mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
419 
420 	return 0;
421 }
422 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)423 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
424 				    struct kvm_mp_state *mp_state)
425 {
426 	int ret = 0;
427 
428 	switch (mp_state->mp_state) {
429 	case KVM_MP_STATE_RUNNABLE:
430 		vcpu->arch.power_off = false;
431 		break;
432 	case KVM_MP_STATE_STOPPED:
433 		vcpu_power_off(vcpu);
434 		break;
435 	default:
436 		ret = -EINVAL;
437 	}
438 
439 	return ret;
440 }
441 
442 /**
443  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
444  * @v:		The VCPU pointer
445  *
446  * If the guest CPU is not waiting for interrupts or an interrupt line is
447  * asserted, the CPU is by definition runnable.
448  */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)449 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
450 {
451 	bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
452 	return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
453 		&& !v->arch.power_off && !v->arch.pause);
454 }
455 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)456 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
457 {
458 	return vcpu_mode_priv(vcpu);
459 }
460 
461 /* Just ensure a guest exit from a particular CPU */
exit_vm_noop(void * info)462 static void exit_vm_noop(void *info)
463 {
464 }
465 
force_vm_exit(const cpumask_t * mask)466 void force_vm_exit(const cpumask_t *mask)
467 {
468 	preempt_disable();
469 	smp_call_function_many(mask, exit_vm_noop, NULL, true);
470 	preempt_enable();
471 }
472 
473 /**
474  * need_new_vmid_gen - check that the VMID is still valid
475  * @vmid: The VMID to check
476  *
477  * return true if there is a new generation of VMIDs being used
478  *
479  * The hardware supports a limited set of values with the value zero reserved
480  * for the host, so we check if an assigned value belongs to a previous
481  * generation, which which requires us to assign a new value. If we're the
482  * first to use a VMID for the new generation, we must flush necessary caches
483  * and TLBs on all CPUs.
484  */
need_new_vmid_gen(struct kvm_vmid * vmid)485 static bool need_new_vmid_gen(struct kvm_vmid *vmid)
486 {
487 	u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
488 	smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
489 	return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
490 }
491 
492 /**
493  * update_vmid - Update the vmid with a valid VMID for the current generation
494  * @kvm: The guest that struct vmid belongs to
495  * @vmid: The stage-2 VMID information struct
496  */
update_vmid(struct kvm_vmid * vmid)497 static void update_vmid(struct kvm_vmid *vmid)
498 {
499 	if (!need_new_vmid_gen(vmid))
500 		return;
501 
502 	spin_lock(&kvm_vmid_lock);
503 
504 	/*
505 	 * We need to re-check the vmid_gen here to ensure that if another vcpu
506 	 * already allocated a valid vmid for this vm, then this vcpu should
507 	 * use the same vmid.
508 	 */
509 	if (!need_new_vmid_gen(vmid)) {
510 		spin_unlock(&kvm_vmid_lock);
511 		return;
512 	}
513 
514 	/* First user of a new VMID generation? */
515 	if (unlikely(kvm_next_vmid == 0)) {
516 		atomic64_inc(&kvm_vmid_gen);
517 		kvm_next_vmid = 1;
518 
519 		/*
520 		 * On SMP we know no other CPUs can use this CPU's or each
521 		 * other's VMID after force_vm_exit returns since the
522 		 * kvm_vmid_lock blocks them from reentry to the guest.
523 		 */
524 		force_vm_exit(cpu_all_mask);
525 		/*
526 		 * Now broadcast TLB + ICACHE invalidation over the inner
527 		 * shareable domain to make sure all data structures are
528 		 * clean.
529 		 */
530 		kvm_call_hyp(__kvm_flush_vm_context);
531 	}
532 
533 	vmid->vmid = kvm_next_vmid;
534 	kvm_next_vmid++;
535 	kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
536 
537 	smp_wmb();
538 	WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
539 
540 	spin_unlock(&kvm_vmid_lock);
541 }
542 
kvm_vcpu_first_run_init(struct kvm_vcpu * vcpu)543 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
544 {
545 	struct kvm *kvm = vcpu->kvm;
546 	int ret = 0;
547 
548 	if (likely(vcpu->arch.has_run_once))
549 		return 0;
550 
551 	if (!kvm_arm_vcpu_is_finalized(vcpu))
552 		return -EPERM;
553 
554 	vcpu->arch.has_run_once = true;
555 
556 	if (likely(irqchip_in_kernel(kvm))) {
557 		/*
558 		 * Map the VGIC hardware resources before running a vcpu the
559 		 * first time on this VM.
560 		 */
561 		if (unlikely(!vgic_ready(kvm))) {
562 			ret = kvm_vgic_map_resources(kvm);
563 			if (ret)
564 				return ret;
565 		}
566 	} else {
567 		/*
568 		 * Tell the rest of the code that there are userspace irqchip
569 		 * VMs in the wild.
570 		 */
571 		static_branch_inc(&userspace_irqchip_in_use);
572 	}
573 
574 	ret = kvm_timer_enable(vcpu);
575 	if (ret)
576 		return ret;
577 
578 	ret = kvm_arm_pmu_v3_enable(vcpu);
579 
580 	return ret;
581 }
582 
kvm_arch_intc_initialized(struct kvm * kvm)583 bool kvm_arch_intc_initialized(struct kvm *kvm)
584 {
585 	return vgic_initialized(kvm);
586 }
587 
kvm_arm_halt_guest(struct kvm * kvm)588 void kvm_arm_halt_guest(struct kvm *kvm)
589 {
590 	int i;
591 	struct kvm_vcpu *vcpu;
592 
593 	kvm_for_each_vcpu(i, vcpu, kvm)
594 		vcpu->arch.pause = true;
595 	kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
596 }
597 
kvm_arm_resume_guest(struct kvm * kvm)598 void kvm_arm_resume_guest(struct kvm *kvm)
599 {
600 	int i;
601 	struct kvm_vcpu *vcpu;
602 
603 	kvm_for_each_vcpu(i, vcpu, kvm) {
604 		vcpu->arch.pause = false;
605 		swake_up_one(kvm_arch_vcpu_wq(vcpu));
606 	}
607 }
608 
vcpu_req_sleep(struct kvm_vcpu * vcpu)609 static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
610 {
611 	struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
612 
613 	swait_event_interruptible_exclusive(*wq, ((!vcpu->arch.power_off) &&
614 				       (!vcpu->arch.pause)));
615 
616 	if (vcpu->arch.power_off || vcpu->arch.pause) {
617 		/* Awaken to handle a signal, request we sleep again later. */
618 		kvm_make_request(KVM_REQ_SLEEP, vcpu);
619 	}
620 
621 	/*
622 	 * Make sure we will observe a potential reset request if we've
623 	 * observed a change to the power state. Pairs with the smp_wmb() in
624 	 * kvm_psci_vcpu_on().
625 	 */
626 	smp_rmb();
627 }
628 
kvm_vcpu_initialized(struct kvm_vcpu * vcpu)629 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
630 {
631 	return vcpu->arch.target >= 0;
632 }
633 
check_vcpu_requests(struct kvm_vcpu * vcpu)634 static void check_vcpu_requests(struct kvm_vcpu *vcpu)
635 {
636 	if (kvm_request_pending(vcpu)) {
637 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
638 			vcpu_req_sleep(vcpu);
639 
640 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
641 			kvm_reset_vcpu(vcpu);
642 
643 		/*
644 		 * Clear IRQ_PENDING requests that were made to guarantee
645 		 * that a VCPU sees new virtual interrupts.
646 		 */
647 		kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
648 	}
649 }
650 
651 /**
652  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
653  * @vcpu:	The VCPU pointer
654  * @run:	The kvm_run structure pointer used for userspace state exchange
655  *
656  * This function is called through the VCPU_RUN ioctl called from user space. It
657  * will execute VM code in a loop until the time slice for the process is used
658  * or some emulation is needed from user space in which case the function will
659  * return with return value 0 and with the kvm_run structure filled in with the
660  * required data for the requested emulation.
661  */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu,struct kvm_run * run)662 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
663 {
664 	int ret;
665 
666 	if (unlikely(!kvm_vcpu_initialized(vcpu)))
667 		return -ENOEXEC;
668 
669 	ret = kvm_vcpu_first_run_init(vcpu);
670 	if (ret)
671 		return ret;
672 
673 	if (run->exit_reason == KVM_EXIT_MMIO) {
674 		ret = kvm_handle_mmio_return(vcpu, vcpu->run);
675 		if (ret)
676 			return ret;
677 	}
678 
679 	if (run->immediate_exit)
680 		return -EINTR;
681 
682 	vcpu_load(vcpu);
683 
684 	kvm_sigset_activate(vcpu);
685 
686 	ret = 1;
687 	run->exit_reason = KVM_EXIT_UNKNOWN;
688 	while (ret > 0) {
689 		/*
690 		 * Check conditions before entering the guest
691 		 */
692 		cond_resched();
693 
694 		update_vmid(&vcpu->kvm->arch.vmid);
695 
696 		check_vcpu_requests(vcpu);
697 
698 		/*
699 		 * Preparing the interrupts to be injected also
700 		 * involves poking the GIC, which must be done in a
701 		 * non-preemptible context.
702 		 */
703 		preempt_disable();
704 
705 		kvm_pmu_flush_hwstate(vcpu);
706 
707 		local_irq_disable();
708 
709 		kvm_vgic_flush_hwstate(vcpu);
710 
711 		/*
712 		 * Exit if we have a signal pending so that we can deliver the
713 		 * signal to user space.
714 		 */
715 		if (signal_pending(current)) {
716 			ret = -EINTR;
717 			run->exit_reason = KVM_EXIT_INTR;
718 		}
719 
720 		/*
721 		 * If we're using a userspace irqchip, then check if we need
722 		 * to tell a userspace irqchip about timer or PMU level
723 		 * changes and if so, exit to userspace (the actual level
724 		 * state gets updated in kvm_timer_update_run and
725 		 * kvm_pmu_update_run below).
726 		 */
727 		if (static_branch_unlikely(&userspace_irqchip_in_use)) {
728 			if (kvm_timer_should_notify_user(vcpu) ||
729 			    kvm_pmu_should_notify_user(vcpu)) {
730 				ret = -EINTR;
731 				run->exit_reason = KVM_EXIT_INTR;
732 			}
733 		}
734 
735 		/*
736 		 * Ensure we set mode to IN_GUEST_MODE after we disable
737 		 * interrupts and before the final VCPU requests check.
738 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
739 		 * Documentation/virt/kvm/vcpu-requests.rst
740 		 */
741 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
742 
743 		if (ret <= 0 || need_new_vmid_gen(&vcpu->kvm->arch.vmid) ||
744 		    kvm_request_pending(vcpu)) {
745 			vcpu->mode = OUTSIDE_GUEST_MODE;
746 			isb(); /* Ensure work in x_flush_hwstate is committed */
747 			kvm_pmu_sync_hwstate(vcpu);
748 			if (static_branch_unlikely(&userspace_irqchip_in_use))
749 				kvm_timer_sync_hwstate(vcpu);
750 			kvm_vgic_sync_hwstate(vcpu);
751 			local_irq_enable();
752 			preempt_enable();
753 			continue;
754 		}
755 
756 		kvm_arm_setup_debug(vcpu);
757 
758 		/**************************************************************
759 		 * Enter the guest
760 		 */
761 		trace_kvm_entry(*vcpu_pc(vcpu));
762 		guest_enter_irqoff();
763 
764 		if (has_vhe()) {
765 			kvm_arm_vhe_guest_enter();
766 			ret = kvm_vcpu_run_vhe(vcpu);
767 			kvm_arm_vhe_guest_exit();
768 		} else {
769 			ret = kvm_call_hyp_ret(__kvm_vcpu_run_nvhe, vcpu);
770 		}
771 
772 		vcpu->mode = OUTSIDE_GUEST_MODE;
773 		vcpu->stat.exits++;
774 		/*
775 		 * Back from guest
776 		 *************************************************************/
777 
778 		kvm_arm_clear_debug(vcpu);
779 
780 		/*
781 		 * We must sync the PMU state before the vgic state so
782 		 * that the vgic can properly sample the updated state of the
783 		 * interrupt line.
784 		 */
785 		kvm_pmu_sync_hwstate(vcpu);
786 
787 		/*
788 		 * Sync the vgic state before syncing the timer state because
789 		 * the timer code needs to know if the virtual timer
790 		 * interrupts are active.
791 		 */
792 		kvm_vgic_sync_hwstate(vcpu);
793 
794 		/*
795 		 * Sync the timer hardware state before enabling interrupts as
796 		 * we don't want vtimer interrupts to race with syncing the
797 		 * timer virtual interrupt state.
798 		 */
799 		if (static_branch_unlikely(&userspace_irqchip_in_use))
800 			kvm_timer_sync_hwstate(vcpu);
801 
802 		kvm_arch_vcpu_ctxsync_fp(vcpu);
803 
804 		/*
805 		 * We may have taken a host interrupt in HYP mode (ie
806 		 * while executing the guest). This interrupt is still
807 		 * pending, as we haven't serviced it yet!
808 		 *
809 		 * We're now back in SVC mode, with interrupts
810 		 * disabled.  Enabling the interrupts now will have
811 		 * the effect of taking the interrupt again, in SVC
812 		 * mode this time.
813 		 */
814 		local_irq_enable();
815 
816 		/*
817 		 * We do local_irq_enable() before calling guest_exit() so
818 		 * that if a timer interrupt hits while running the guest we
819 		 * account that tick as being spent in the guest.  We enable
820 		 * preemption after calling guest_exit() so that if we get
821 		 * preempted we make sure ticks after that is not counted as
822 		 * guest time.
823 		 */
824 		guest_exit();
825 		trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
826 
827 		/* Exit types that need handling before we can be preempted */
828 		handle_exit_early(vcpu, run, ret);
829 
830 		preempt_enable();
831 
832 		ret = handle_exit(vcpu, run, ret);
833 	}
834 
835 	/* Tell userspace about in-kernel device output levels */
836 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
837 		kvm_timer_update_run(vcpu);
838 		kvm_pmu_update_run(vcpu);
839 	}
840 
841 	kvm_sigset_deactivate(vcpu);
842 
843 	vcpu_put(vcpu);
844 	return ret;
845 }
846 
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)847 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
848 {
849 	int bit_index;
850 	bool set;
851 	unsigned long *hcr;
852 
853 	if (number == KVM_ARM_IRQ_CPU_IRQ)
854 		bit_index = __ffs(HCR_VI);
855 	else /* KVM_ARM_IRQ_CPU_FIQ */
856 		bit_index = __ffs(HCR_VF);
857 
858 	hcr = vcpu_hcr(vcpu);
859 	if (level)
860 		set = test_and_set_bit(bit_index, hcr);
861 	else
862 		set = test_and_clear_bit(bit_index, hcr);
863 
864 	/*
865 	 * If we didn't change anything, no need to wake up or kick other CPUs
866 	 */
867 	if (set == level)
868 		return 0;
869 
870 	/*
871 	 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
872 	 * trigger a world-switch round on the running physical CPU to set the
873 	 * virtual IRQ/FIQ fields in the HCR appropriately.
874 	 */
875 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
876 	kvm_vcpu_kick(vcpu);
877 
878 	return 0;
879 }
880 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)881 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
882 			  bool line_status)
883 {
884 	u32 irq = irq_level->irq;
885 	unsigned int irq_type, vcpu_idx, irq_num;
886 	int nrcpus = atomic_read(&kvm->online_vcpus);
887 	struct kvm_vcpu *vcpu = NULL;
888 	bool level = irq_level->level;
889 
890 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
891 	vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
892 	vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
893 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
894 
895 	trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
896 
897 	switch (irq_type) {
898 	case KVM_ARM_IRQ_TYPE_CPU:
899 		if (irqchip_in_kernel(kvm))
900 			return -ENXIO;
901 
902 		if (vcpu_idx >= nrcpus)
903 			return -EINVAL;
904 
905 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
906 		if (!vcpu)
907 			return -EINVAL;
908 
909 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
910 			return -EINVAL;
911 
912 		return vcpu_interrupt_line(vcpu, irq_num, level);
913 	case KVM_ARM_IRQ_TYPE_PPI:
914 		if (!irqchip_in_kernel(kvm))
915 			return -ENXIO;
916 
917 		if (vcpu_idx >= nrcpus)
918 			return -EINVAL;
919 
920 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
921 		if (!vcpu)
922 			return -EINVAL;
923 
924 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
925 			return -EINVAL;
926 
927 		return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
928 	case KVM_ARM_IRQ_TYPE_SPI:
929 		if (!irqchip_in_kernel(kvm))
930 			return -ENXIO;
931 
932 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
933 			return -EINVAL;
934 
935 		return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
936 	}
937 
938 	return -EINVAL;
939 }
940 
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)941 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
942 			       const struct kvm_vcpu_init *init)
943 {
944 	unsigned int i, ret;
945 	int phys_target = kvm_target_cpu();
946 
947 	if (init->target != phys_target)
948 		return -EINVAL;
949 
950 	/*
951 	 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
952 	 * use the same target.
953 	 */
954 	if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
955 		return -EINVAL;
956 
957 	/* -ENOENT for unknown features, -EINVAL for invalid combinations. */
958 	for (i = 0; i < sizeof(init->features) * 8; i++) {
959 		bool set = (init->features[i / 32] & (1 << (i % 32)));
960 
961 		if (set && i >= KVM_VCPU_MAX_FEATURES)
962 			return -ENOENT;
963 
964 		/*
965 		 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
966 		 * use the same feature set.
967 		 */
968 		if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
969 		    test_bit(i, vcpu->arch.features) != set)
970 			return -EINVAL;
971 
972 		if (set)
973 			set_bit(i, vcpu->arch.features);
974 	}
975 
976 	vcpu->arch.target = phys_target;
977 
978 	/* Now we know what it is, we can reset it. */
979 	ret = kvm_reset_vcpu(vcpu);
980 	if (ret) {
981 		vcpu->arch.target = -1;
982 		bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
983 	}
984 
985 	return ret;
986 }
987 
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)988 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
989 					 struct kvm_vcpu_init *init)
990 {
991 	int ret;
992 
993 	ret = kvm_vcpu_set_target(vcpu, init);
994 	if (ret)
995 		return ret;
996 
997 	/*
998 	 * Ensure a rebooted VM will fault in RAM pages and detect if the
999 	 * guest MMU is turned off and flush the caches as needed.
1000 	 */
1001 	if (vcpu->arch.has_run_once)
1002 		stage2_unmap_vm(vcpu->kvm);
1003 
1004 	vcpu_reset_hcr(vcpu);
1005 
1006 	/*
1007 	 * Handle the "start in power-off" case.
1008 	 */
1009 	if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1010 		vcpu_power_off(vcpu);
1011 	else
1012 		vcpu->arch.power_off = false;
1013 
1014 	return 0;
1015 }
1016 
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1017 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1018 				 struct kvm_device_attr *attr)
1019 {
1020 	int ret = -ENXIO;
1021 
1022 	switch (attr->group) {
1023 	default:
1024 		ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1025 		break;
1026 	}
1027 
1028 	return ret;
1029 }
1030 
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1031 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1032 				 struct kvm_device_attr *attr)
1033 {
1034 	int ret = -ENXIO;
1035 
1036 	switch (attr->group) {
1037 	default:
1038 		ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1039 		break;
1040 	}
1041 
1042 	return ret;
1043 }
1044 
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1045 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1046 				 struct kvm_device_attr *attr)
1047 {
1048 	int ret = -ENXIO;
1049 
1050 	switch (attr->group) {
1051 	default:
1052 		ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1053 		break;
1054 	}
1055 
1056 	return ret;
1057 }
1058 
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1059 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1060 				   struct kvm_vcpu_events *events)
1061 {
1062 	memset(events, 0, sizeof(*events));
1063 
1064 	return __kvm_arm_vcpu_get_events(vcpu, events);
1065 }
1066 
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1067 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1068 				   struct kvm_vcpu_events *events)
1069 {
1070 	int i;
1071 
1072 	/* check whether the reserved field is zero */
1073 	for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1074 		if (events->reserved[i])
1075 			return -EINVAL;
1076 
1077 	/* check whether the pad field is zero */
1078 	for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1079 		if (events->exception.pad[i])
1080 			return -EINVAL;
1081 
1082 	return __kvm_arm_vcpu_set_events(vcpu, events);
1083 }
1084 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1085 long kvm_arch_vcpu_ioctl(struct file *filp,
1086 			 unsigned int ioctl, unsigned long arg)
1087 {
1088 	struct kvm_vcpu *vcpu = filp->private_data;
1089 	void __user *argp = (void __user *)arg;
1090 	struct kvm_device_attr attr;
1091 	long r;
1092 
1093 	switch (ioctl) {
1094 	case KVM_ARM_VCPU_INIT: {
1095 		struct kvm_vcpu_init init;
1096 
1097 		r = -EFAULT;
1098 		if (copy_from_user(&init, argp, sizeof(init)))
1099 			break;
1100 
1101 		r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1102 		break;
1103 	}
1104 	case KVM_SET_ONE_REG:
1105 	case KVM_GET_ONE_REG: {
1106 		struct kvm_one_reg reg;
1107 
1108 		r = -ENOEXEC;
1109 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1110 			break;
1111 
1112 		r = -EFAULT;
1113 		if (copy_from_user(&reg, argp, sizeof(reg)))
1114 			break;
1115 
1116 		if (ioctl == KVM_SET_ONE_REG)
1117 			r = kvm_arm_set_reg(vcpu, &reg);
1118 		else
1119 			r = kvm_arm_get_reg(vcpu, &reg);
1120 		break;
1121 	}
1122 	case KVM_GET_REG_LIST: {
1123 		struct kvm_reg_list __user *user_list = argp;
1124 		struct kvm_reg_list reg_list;
1125 		unsigned n;
1126 
1127 		r = -ENOEXEC;
1128 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1129 			break;
1130 
1131 		r = -EPERM;
1132 		if (!kvm_arm_vcpu_is_finalized(vcpu))
1133 			break;
1134 
1135 		r = -EFAULT;
1136 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1137 			break;
1138 		n = reg_list.n;
1139 		reg_list.n = kvm_arm_num_regs(vcpu);
1140 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1141 			break;
1142 		r = -E2BIG;
1143 		if (n < reg_list.n)
1144 			break;
1145 		r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1146 		break;
1147 	}
1148 	case KVM_SET_DEVICE_ATTR: {
1149 		r = -EFAULT;
1150 		if (copy_from_user(&attr, argp, sizeof(attr)))
1151 			break;
1152 		r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1153 		break;
1154 	}
1155 	case KVM_GET_DEVICE_ATTR: {
1156 		r = -EFAULT;
1157 		if (copy_from_user(&attr, argp, sizeof(attr)))
1158 			break;
1159 		r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1160 		break;
1161 	}
1162 	case KVM_HAS_DEVICE_ATTR: {
1163 		r = -EFAULT;
1164 		if (copy_from_user(&attr, argp, sizeof(attr)))
1165 			break;
1166 		r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1167 		break;
1168 	}
1169 	case KVM_GET_VCPU_EVENTS: {
1170 		struct kvm_vcpu_events events;
1171 
1172 		if (kvm_arm_vcpu_get_events(vcpu, &events))
1173 			return -EINVAL;
1174 
1175 		if (copy_to_user(argp, &events, sizeof(events)))
1176 			return -EFAULT;
1177 
1178 		return 0;
1179 	}
1180 	case KVM_SET_VCPU_EVENTS: {
1181 		struct kvm_vcpu_events events;
1182 
1183 		if (copy_from_user(&events, argp, sizeof(events)))
1184 			return -EFAULT;
1185 
1186 		return kvm_arm_vcpu_set_events(vcpu, &events);
1187 	}
1188 	case KVM_ARM_VCPU_FINALIZE: {
1189 		int what;
1190 
1191 		if (!kvm_vcpu_initialized(vcpu))
1192 			return -ENOEXEC;
1193 
1194 		if (get_user(what, (const int __user *)argp))
1195 			return -EFAULT;
1196 
1197 		return kvm_arm_vcpu_finalize(vcpu, what);
1198 	}
1199 	default:
1200 		r = -EINVAL;
1201 	}
1202 
1203 	return r;
1204 }
1205 
1206 /**
1207  * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
1208  * @kvm: kvm instance
1209  * @log: slot id and address to which we copy the log
1210  *
1211  * Steps 1-4 below provide general overview of dirty page logging. See
1212  * kvm_get_dirty_log_protect() function description for additional details.
1213  *
1214  * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
1215  * always flush the TLB (step 4) even if previous step failed  and the dirty
1216  * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
1217  * does not preclude user space subsequent dirty log read. Flushing TLB ensures
1218  * writes will be marked dirty for next log read.
1219  *
1220  *   1. Take a snapshot of the bit and clear it if needed.
1221  *   2. Write protect the corresponding page.
1222  *   3. Copy the snapshot to the userspace.
1223  *   4. Flush TLB's if needed.
1224  */
kvm_vm_ioctl_get_dirty_log(struct kvm * kvm,struct kvm_dirty_log * log)1225 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
1226 {
1227 	bool flush = false;
1228 	int r;
1229 
1230 	mutex_lock(&kvm->slots_lock);
1231 
1232 	r = kvm_get_dirty_log_protect(kvm, log, &flush);
1233 
1234 	if (flush)
1235 		kvm_flush_remote_tlbs(kvm);
1236 
1237 	mutex_unlock(&kvm->slots_lock);
1238 	return r;
1239 }
1240 
kvm_vm_ioctl_clear_dirty_log(struct kvm * kvm,struct kvm_clear_dirty_log * log)1241 int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
1242 {
1243 	bool flush = false;
1244 	int r;
1245 
1246 	mutex_lock(&kvm->slots_lock);
1247 
1248 	r = kvm_clear_dirty_log_protect(kvm, log, &flush);
1249 
1250 	if (flush)
1251 		kvm_flush_remote_tlbs(kvm);
1252 
1253 	mutex_unlock(&kvm->slots_lock);
1254 	return r;
1255 }
1256 
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1257 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1258 					struct kvm_arm_device_addr *dev_addr)
1259 {
1260 	unsigned long dev_id, type;
1261 
1262 	dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
1263 		KVM_ARM_DEVICE_ID_SHIFT;
1264 	type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
1265 		KVM_ARM_DEVICE_TYPE_SHIFT;
1266 
1267 	switch (dev_id) {
1268 	case KVM_ARM_DEVICE_VGIC_V2:
1269 		if (!vgic_present)
1270 			return -ENXIO;
1271 		return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
1272 	default:
1273 		return -ENODEV;
1274 	}
1275 }
1276 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1277 long kvm_arch_vm_ioctl(struct file *filp,
1278 		       unsigned int ioctl, unsigned long arg)
1279 {
1280 	struct kvm *kvm = filp->private_data;
1281 	void __user *argp = (void __user *)arg;
1282 
1283 	switch (ioctl) {
1284 	case KVM_CREATE_IRQCHIP: {
1285 		int ret;
1286 		if (!vgic_present)
1287 			return -ENXIO;
1288 		mutex_lock(&kvm->lock);
1289 		ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1290 		mutex_unlock(&kvm->lock);
1291 		return ret;
1292 	}
1293 	case KVM_ARM_SET_DEVICE_ADDR: {
1294 		struct kvm_arm_device_addr dev_addr;
1295 
1296 		if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1297 			return -EFAULT;
1298 		return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1299 	}
1300 	case KVM_ARM_PREFERRED_TARGET: {
1301 		int err;
1302 		struct kvm_vcpu_init init;
1303 
1304 		err = kvm_vcpu_preferred_target(&init);
1305 		if (err)
1306 			return err;
1307 
1308 		if (copy_to_user(argp, &init, sizeof(init)))
1309 			return -EFAULT;
1310 
1311 		return 0;
1312 	}
1313 	default:
1314 		return -EINVAL;
1315 	}
1316 }
1317 
cpu_init_hyp_mode(void * dummy)1318 static void cpu_init_hyp_mode(void *dummy)
1319 {
1320 	phys_addr_t pgd_ptr;
1321 	unsigned long hyp_stack_ptr;
1322 	unsigned long stack_page;
1323 	unsigned long vector_ptr;
1324 
1325 	/* Switch from the HYP stub to our own HYP init vector */
1326 	__hyp_set_vectors(kvm_get_idmap_vector());
1327 
1328 	pgd_ptr = kvm_mmu_get_httbr();
1329 	stack_page = __this_cpu_read(kvm_arm_hyp_stack_page);
1330 	hyp_stack_ptr = stack_page + PAGE_SIZE;
1331 	vector_ptr = (unsigned long)kvm_get_hyp_vector();
1332 
1333 	__cpu_init_hyp_mode(pgd_ptr, hyp_stack_ptr, vector_ptr);
1334 	__cpu_init_stage2();
1335 }
1336 
cpu_hyp_reset(void)1337 static void cpu_hyp_reset(void)
1338 {
1339 	if (!is_kernel_in_hyp_mode())
1340 		__hyp_reset_vectors();
1341 }
1342 
cpu_hyp_reinit(void)1343 static void cpu_hyp_reinit(void)
1344 {
1345 	kvm_init_host_cpu_context(&this_cpu_ptr(&kvm_host_data)->host_ctxt);
1346 
1347 	cpu_hyp_reset();
1348 
1349 	if (is_kernel_in_hyp_mode())
1350 		kvm_timer_init_vhe();
1351 	else
1352 		cpu_init_hyp_mode(NULL);
1353 
1354 	kvm_arm_init_debug();
1355 
1356 	if (vgic_present)
1357 		kvm_vgic_init_cpu_hardware();
1358 }
1359 
_kvm_arch_hardware_enable(void * discard)1360 static void _kvm_arch_hardware_enable(void *discard)
1361 {
1362 	if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1363 		cpu_hyp_reinit();
1364 		__this_cpu_write(kvm_arm_hardware_enabled, 1);
1365 	}
1366 }
1367 
kvm_arch_hardware_enable(void)1368 int kvm_arch_hardware_enable(void)
1369 {
1370 	_kvm_arch_hardware_enable(NULL);
1371 	return 0;
1372 }
1373 
_kvm_arch_hardware_disable(void * discard)1374 static void _kvm_arch_hardware_disable(void *discard)
1375 {
1376 	if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1377 		cpu_hyp_reset();
1378 		__this_cpu_write(kvm_arm_hardware_enabled, 0);
1379 	}
1380 }
1381 
kvm_arch_hardware_disable(void)1382 void kvm_arch_hardware_disable(void)
1383 {
1384 	_kvm_arch_hardware_disable(NULL);
1385 }
1386 
1387 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)1388 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1389 				    unsigned long cmd,
1390 				    void *v)
1391 {
1392 	/*
1393 	 * kvm_arm_hardware_enabled is left with its old value over
1394 	 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1395 	 * re-enable hyp.
1396 	 */
1397 	switch (cmd) {
1398 	case CPU_PM_ENTER:
1399 		if (__this_cpu_read(kvm_arm_hardware_enabled))
1400 			/*
1401 			 * don't update kvm_arm_hardware_enabled here
1402 			 * so that the hardware will be re-enabled
1403 			 * when we resume. See below.
1404 			 */
1405 			cpu_hyp_reset();
1406 
1407 		return NOTIFY_OK;
1408 	case CPU_PM_ENTER_FAILED:
1409 	case CPU_PM_EXIT:
1410 		if (__this_cpu_read(kvm_arm_hardware_enabled))
1411 			/* The hardware was enabled before suspend. */
1412 			cpu_hyp_reinit();
1413 
1414 		return NOTIFY_OK;
1415 
1416 	default:
1417 		return NOTIFY_DONE;
1418 	}
1419 }
1420 
1421 static struct notifier_block hyp_init_cpu_pm_nb = {
1422 	.notifier_call = hyp_init_cpu_pm_notifier,
1423 };
1424 
hyp_cpu_pm_init(void)1425 static void __init hyp_cpu_pm_init(void)
1426 {
1427 	cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1428 }
hyp_cpu_pm_exit(void)1429 static void __init hyp_cpu_pm_exit(void)
1430 {
1431 	cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1432 }
1433 #else
hyp_cpu_pm_init(void)1434 static inline void hyp_cpu_pm_init(void)
1435 {
1436 }
hyp_cpu_pm_exit(void)1437 static inline void hyp_cpu_pm_exit(void)
1438 {
1439 }
1440 #endif
1441 
init_common_resources(void)1442 static int init_common_resources(void)
1443 {
1444 	kvm_set_ipa_limit();
1445 
1446 	return 0;
1447 }
1448 
init_subsystems(void)1449 static int init_subsystems(void)
1450 {
1451 	int err = 0;
1452 
1453 	/*
1454 	 * Enable hardware so that subsystem initialisation can access EL2.
1455 	 */
1456 	on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1457 
1458 	/*
1459 	 * Register CPU lower-power notifier
1460 	 */
1461 	hyp_cpu_pm_init();
1462 
1463 	/*
1464 	 * Init HYP view of VGIC
1465 	 */
1466 	err = kvm_vgic_hyp_init();
1467 	switch (err) {
1468 	case 0:
1469 		vgic_present = true;
1470 		break;
1471 	case -ENODEV:
1472 	case -ENXIO:
1473 		vgic_present = false;
1474 		err = 0;
1475 		break;
1476 	default:
1477 		goto out;
1478 	}
1479 
1480 	/*
1481 	 * Init HYP architected timer support
1482 	 */
1483 	err = kvm_timer_hyp_init(vgic_present);
1484 	if (err)
1485 		goto out;
1486 
1487 	kvm_perf_init();
1488 	kvm_coproc_table_init();
1489 
1490 out:
1491 	on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1492 
1493 	return err;
1494 }
1495 
teardown_hyp_mode(void)1496 static void teardown_hyp_mode(void)
1497 {
1498 	int cpu;
1499 
1500 	free_hyp_pgds();
1501 	for_each_possible_cpu(cpu)
1502 		free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1503 	hyp_cpu_pm_exit();
1504 }
1505 
1506 /**
1507  * Inits Hyp-mode on all online CPUs
1508  */
init_hyp_mode(void)1509 static int init_hyp_mode(void)
1510 {
1511 	int cpu;
1512 	int err = 0;
1513 
1514 	/*
1515 	 * Allocate Hyp PGD and setup Hyp identity mapping
1516 	 */
1517 	err = kvm_mmu_init();
1518 	if (err)
1519 		goto out_err;
1520 
1521 	/*
1522 	 * Allocate stack pages for Hypervisor-mode
1523 	 */
1524 	for_each_possible_cpu(cpu) {
1525 		unsigned long stack_page;
1526 
1527 		stack_page = __get_free_page(GFP_KERNEL);
1528 		if (!stack_page) {
1529 			err = -ENOMEM;
1530 			goto out_err;
1531 		}
1532 
1533 		per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1534 	}
1535 
1536 	/*
1537 	 * Map the Hyp-code called directly from the host
1538 	 */
1539 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
1540 				  kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
1541 	if (err) {
1542 		kvm_err("Cannot map world-switch code\n");
1543 		goto out_err;
1544 	}
1545 
1546 	err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
1547 				  kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
1548 	if (err) {
1549 		kvm_err("Cannot map rodata section\n");
1550 		goto out_err;
1551 	}
1552 
1553 	err = create_hyp_mappings(kvm_ksym_ref(__bss_start),
1554 				  kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
1555 	if (err) {
1556 		kvm_err("Cannot map bss section\n");
1557 		goto out_err;
1558 	}
1559 
1560 	err = kvm_map_vectors();
1561 	if (err) {
1562 		kvm_err("Cannot map vectors\n");
1563 		goto out_err;
1564 	}
1565 
1566 	/*
1567 	 * Map the Hyp stack pages
1568 	 */
1569 	for_each_possible_cpu(cpu) {
1570 		char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
1571 		err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
1572 					  PAGE_HYP);
1573 
1574 		if (err) {
1575 			kvm_err("Cannot map hyp stack\n");
1576 			goto out_err;
1577 		}
1578 	}
1579 
1580 	for_each_possible_cpu(cpu) {
1581 		kvm_host_data_t *cpu_data;
1582 
1583 		cpu_data = per_cpu_ptr(&kvm_host_data, cpu);
1584 		err = create_hyp_mappings(cpu_data, cpu_data + 1, PAGE_HYP);
1585 
1586 		if (err) {
1587 			kvm_err("Cannot map host CPU state: %d\n", err);
1588 			goto out_err;
1589 		}
1590 	}
1591 
1592 	err = hyp_map_aux_data();
1593 	if (err)
1594 		kvm_err("Cannot map host auxiliary data: %d\n", err);
1595 
1596 	return 0;
1597 
1598 out_err:
1599 	teardown_hyp_mode();
1600 	kvm_err("error initializing Hyp mode: %d\n", err);
1601 	return err;
1602 }
1603 
check_kvm_target_cpu(void * ret)1604 static void check_kvm_target_cpu(void *ret)
1605 {
1606 	*(int *)ret = kvm_target_cpu();
1607 }
1608 
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)1609 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
1610 {
1611 	struct kvm_vcpu *vcpu;
1612 	int i;
1613 
1614 	mpidr &= MPIDR_HWID_BITMASK;
1615 	kvm_for_each_vcpu(i, vcpu, kvm) {
1616 		if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
1617 			return vcpu;
1618 	}
1619 	return NULL;
1620 }
1621 
kvm_arch_has_irq_bypass(void)1622 bool kvm_arch_has_irq_bypass(void)
1623 {
1624 	return true;
1625 }
1626 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)1627 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
1628 				      struct irq_bypass_producer *prod)
1629 {
1630 	struct kvm_kernel_irqfd *irqfd =
1631 		container_of(cons, struct kvm_kernel_irqfd, consumer);
1632 
1633 	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
1634 					  &irqfd->irq_entry);
1635 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)1636 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
1637 				      struct irq_bypass_producer *prod)
1638 {
1639 	struct kvm_kernel_irqfd *irqfd =
1640 		container_of(cons, struct kvm_kernel_irqfd, consumer);
1641 
1642 	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
1643 				     &irqfd->irq_entry);
1644 }
1645 
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)1646 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
1647 {
1648 	struct kvm_kernel_irqfd *irqfd =
1649 		container_of(cons, struct kvm_kernel_irqfd, consumer);
1650 
1651 	kvm_arm_halt_guest(irqfd->kvm);
1652 }
1653 
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)1654 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
1655 {
1656 	struct kvm_kernel_irqfd *irqfd =
1657 		container_of(cons, struct kvm_kernel_irqfd, consumer);
1658 
1659 	kvm_arm_resume_guest(irqfd->kvm);
1660 }
1661 
1662 /**
1663  * Initialize Hyp-mode and memory mappings on all CPUs.
1664  */
kvm_arch_init(void * opaque)1665 int kvm_arch_init(void *opaque)
1666 {
1667 	int err;
1668 	int ret, cpu;
1669 	bool in_hyp_mode;
1670 
1671 	if (!is_hyp_mode_available()) {
1672 		kvm_info("HYP mode not available\n");
1673 		return -ENODEV;
1674 	}
1675 
1676 	in_hyp_mode = is_kernel_in_hyp_mode();
1677 
1678 	if (!in_hyp_mode && kvm_arch_requires_vhe()) {
1679 		kvm_pr_unimpl("CPU unsupported in non-VHE mode, not initializing\n");
1680 		return -ENODEV;
1681 	}
1682 
1683 	for_each_online_cpu(cpu) {
1684 		smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1);
1685 		if (ret < 0) {
1686 			kvm_err("Error, CPU %d not supported!\n", cpu);
1687 			return -ENODEV;
1688 		}
1689 	}
1690 
1691 	err = init_common_resources();
1692 	if (err)
1693 		return err;
1694 
1695 	err = kvm_arm_init_sve();
1696 	if (err)
1697 		return err;
1698 
1699 	if (!in_hyp_mode) {
1700 		err = init_hyp_mode();
1701 		if (err)
1702 			goto out_err;
1703 	}
1704 
1705 	err = init_subsystems();
1706 	if (err)
1707 		goto out_hyp;
1708 
1709 	if (in_hyp_mode)
1710 		kvm_info("VHE mode initialized successfully\n");
1711 	else
1712 		kvm_info("Hyp mode initialized successfully\n");
1713 
1714 	return 0;
1715 
1716 out_hyp:
1717 	if (!in_hyp_mode)
1718 		teardown_hyp_mode();
1719 out_err:
1720 	return err;
1721 }
1722 
1723 /* NOP: Compiling as a module not supported */
kvm_arch_exit(void)1724 void kvm_arch_exit(void)
1725 {
1726 	kvm_perf_teardown();
1727 }
1728 
arm_init(void)1729 static int arm_init(void)
1730 {
1731 	int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1732 	return rc;
1733 }
1734 
1735 module_init(arm_init);
1736