xref: /linux/arch/riscv/kvm/vcpu.c (revision 6093a688a07da07808f0122f9aa2a3eed250d853)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2019 Western Digital Corporation or its affiliates.
4  *
5  * Authors:
6  *     Anup Patel <anup.patel@wdc.com>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/entry-kvm.h>
11 #include <linux/errno.h>
12 #include <linux/err.h>
13 #include <linux/kdebug.h>
14 #include <linux/module.h>
15 #include <linux/percpu.h>
16 #include <linux/vmalloc.h>
17 #include <linux/sched/signal.h>
18 #include <linux/fs.h>
19 #include <linux/kvm_host.h>
20 #include <asm/cacheflush.h>
21 #include <asm/kvm_mmu.h>
22 #include <asm/kvm_nacl.h>
23 #include <asm/kvm_vcpu_vector.h>
24 
25 #define CREATE_TRACE_POINTS
26 #include "trace.h"
27 
28 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
29 	KVM_GENERIC_VCPU_STATS(),
30 	STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
31 	STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
32 	STATS_DESC_COUNTER(VCPU, wrs_exit_stat),
33 	STATS_DESC_COUNTER(VCPU, mmio_exit_user),
34 	STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
35 	STATS_DESC_COUNTER(VCPU, csr_exit_user),
36 	STATS_DESC_COUNTER(VCPU, csr_exit_kernel),
37 	STATS_DESC_COUNTER(VCPU, signal_exits),
38 	STATS_DESC_COUNTER(VCPU, exits),
39 	STATS_DESC_COUNTER(VCPU, instr_illegal_exits),
40 	STATS_DESC_COUNTER(VCPU, load_misaligned_exits),
41 	STATS_DESC_COUNTER(VCPU, store_misaligned_exits),
42 	STATS_DESC_COUNTER(VCPU, load_access_exits),
43 	STATS_DESC_COUNTER(VCPU, store_access_exits),
44 };
45 
46 const struct kvm_stats_header kvm_vcpu_stats_header = {
47 	.name_size = KVM_STATS_NAME_SIZE,
48 	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
49 	.id_offset = sizeof(struct kvm_stats_header),
50 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
51 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
52 		       sizeof(kvm_vcpu_stats_desc),
53 };
54 
55 static void kvm_riscv_vcpu_context_reset(struct kvm_vcpu *vcpu,
56 					 bool kvm_sbi_reset)
57 {
58 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
59 	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
60 	void *vector_datap = cntx->vector.datap;
61 
62 	memset(cntx, 0, sizeof(*cntx));
63 	memset(csr, 0, sizeof(*csr));
64 	memset(&vcpu->arch.smstateen_csr, 0, sizeof(vcpu->arch.smstateen_csr));
65 
66 	/* Restore datap as it's not a part of the guest context. */
67 	cntx->vector.datap = vector_datap;
68 
69 	if (kvm_sbi_reset)
70 		kvm_riscv_vcpu_sbi_load_reset_state(vcpu);
71 
72 	/* Setup reset state of shadow SSTATUS and HSTATUS CSRs */
73 	cntx->sstatus = SR_SPP | SR_SPIE;
74 
75 	cntx->hstatus |= HSTATUS_VTW;
76 	cntx->hstatus |= HSTATUS_SPVP;
77 	cntx->hstatus |= HSTATUS_SPV;
78 }
79 
80 static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu, bool kvm_sbi_reset)
81 {
82 	bool loaded;
83 
84 	/**
85 	 * The preemption should be disabled here because it races with
86 	 * kvm_sched_out/kvm_sched_in(called from preempt notifiers) which
87 	 * also calls vcpu_load/put.
88 	 */
89 	get_cpu();
90 	loaded = (vcpu->cpu != -1);
91 	if (loaded)
92 		kvm_arch_vcpu_put(vcpu);
93 
94 	vcpu->arch.last_exit_cpu = -1;
95 
96 	kvm_riscv_vcpu_context_reset(vcpu, kvm_sbi_reset);
97 
98 	kvm_riscv_vcpu_fp_reset(vcpu);
99 
100 	kvm_riscv_vcpu_vector_reset(vcpu);
101 
102 	kvm_riscv_vcpu_timer_reset(vcpu);
103 
104 	kvm_riscv_vcpu_aia_reset(vcpu);
105 
106 	bitmap_zero(vcpu->arch.irqs_pending, KVM_RISCV_VCPU_NR_IRQS);
107 	bitmap_zero(vcpu->arch.irqs_pending_mask, KVM_RISCV_VCPU_NR_IRQS);
108 
109 	kvm_riscv_vcpu_pmu_reset(vcpu);
110 
111 	vcpu->arch.hfence_head = 0;
112 	vcpu->arch.hfence_tail = 0;
113 	memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue));
114 
115 	kvm_riscv_vcpu_sbi_reset(vcpu);
116 
117 	/* Reset the guest CSRs for hotplug usecase */
118 	if (loaded)
119 		kvm_arch_vcpu_load(vcpu, smp_processor_id());
120 	put_cpu();
121 }
122 
123 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
124 {
125 	return 0;
126 }
127 
128 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
129 {
130 	int rc;
131 
132 	spin_lock_init(&vcpu->arch.mp_state_lock);
133 
134 	/* Mark this VCPU never ran */
135 	vcpu->arch.ran_atleast_once = false;
136 
137 	vcpu->arch.cfg.hedeleg = KVM_HEDELEG_DEFAULT;
138 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
139 	bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX);
140 
141 	/* Setup ISA features available to VCPU */
142 	kvm_riscv_vcpu_setup_isa(vcpu);
143 
144 	/* Setup vendor, arch, and implementation details */
145 	vcpu->arch.mvendorid = sbi_get_mvendorid();
146 	vcpu->arch.marchid = sbi_get_marchid();
147 	vcpu->arch.mimpid = sbi_get_mimpid();
148 
149 	/* Setup VCPU hfence queue */
150 	spin_lock_init(&vcpu->arch.hfence_lock);
151 
152 	spin_lock_init(&vcpu->arch.reset_state.lock);
153 
154 	rc = kvm_riscv_vcpu_alloc_vector_context(vcpu);
155 	if (rc)
156 		return rc;
157 
158 	/* Setup VCPU timer */
159 	kvm_riscv_vcpu_timer_init(vcpu);
160 
161 	/* setup performance monitoring */
162 	kvm_riscv_vcpu_pmu_init(vcpu);
163 
164 	/* Setup VCPU AIA */
165 	kvm_riscv_vcpu_aia_init(vcpu);
166 
167 	/*
168 	 * Setup SBI extensions
169 	 * NOTE: This must be the last thing to be initialized.
170 	 */
171 	kvm_riscv_vcpu_sbi_init(vcpu);
172 
173 	/* Reset VCPU */
174 	kvm_riscv_reset_vcpu(vcpu, false);
175 
176 	return 0;
177 }
178 
179 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
180 {
181 	/**
182 	 * vcpu with id 0 is the designated boot cpu.
183 	 * Keep all vcpus with non-zero id in power-off state so that
184 	 * they can be brought up using SBI HSM extension.
185 	 */
186 	if (vcpu->vcpu_idx != 0)
187 		kvm_riscv_vcpu_power_off(vcpu);
188 }
189 
190 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
191 {
192 	kvm_riscv_vcpu_sbi_deinit(vcpu);
193 
194 	/* Cleanup VCPU AIA context */
195 	kvm_riscv_vcpu_aia_deinit(vcpu);
196 
197 	/* Cleanup VCPU timer */
198 	kvm_riscv_vcpu_timer_deinit(vcpu);
199 
200 	kvm_riscv_vcpu_pmu_deinit(vcpu);
201 
202 	/* Free unused pages pre-allocated for G-stage page table mappings */
203 	kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
204 
205 	/* Free vector context space for host and guest kernel */
206 	kvm_riscv_vcpu_free_vector_context(vcpu);
207 }
208 
209 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
210 {
211 	return kvm_riscv_vcpu_timer_pending(vcpu);
212 }
213 
214 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
215 {
216 	return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) &&
217 		!kvm_riscv_vcpu_stopped(vcpu) && !vcpu->arch.pause);
218 }
219 
220 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
221 {
222 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
223 }
224 
225 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
226 {
227 	return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false;
228 }
229 
230 #ifdef CONFIG_GUEST_PERF_EVENTS
231 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
232 {
233 	return vcpu->arch.guest_context.sepc;
234 }
235 #endif
236 
237 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
238 {
239 	return VM_FAULT_SIGBUS;
240 }
241 
242 long kvm_arch_vcpu_async_ioctl(struct file *filp,
243 			       unsigned int ioctl, unsigned long arg)
244 {
245 	struct kvm_vcpu *vcpu = filp->private_data;
246 	void __user *argp = (void __user *)arg;
247 
248 	if (ioctl == KVM_INTERRUPT) {
249 		struct kvm_interrupt irq;
250 
251 		if (copy_from_user(&irq, argp, sizeof(irq)))
252 			return -EFAULT;
253 
254 		if (irq.irq == KVM_INTERRUPT_SET)
255 			return kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT);
256 		else
257 			return kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
258 	}
259 
260 	return -ENOIOCTLCMD;
261 }
262 
263 long kvm_arch_vcpu_ioctl(struct file *filp,
264 			 unsigned int ioctl, unsigned long arg)
265 {
266 	struct kvm_vcpu *vcpu = filp->private_data;
267 	void __user *argp = (void __user *)arg;
268 	long r = -EINVAL;
269 
270 	switch (ioctl) {
271 	case KVM_SET_ONE_REG:
272 	case KVM_GET_ONE_REG: {
273 		struct kvm_one_reg reg;
274 
275 		r = -EFAULT;
276 		if (copy_from_user(&reg, argp, sizeof(reg)))
277 			break;
278 
279 		if (ioctl == KVM_SET_ONE_REG)
280 			r = kvm_riscv_vcpu_set_reg(vcpu, &reg);
281 		else
282 			r = kvm_riscv_vcpu_get_reg(vcpu, &reg);
283 		break;
284 	}
285 	case KVM_GET_REG_LIST: {
286 		struct kvm_reg_list __user *user_list = argp;
287 		struct kvm_reg_list reg_list;
288 		unsigned int n;
289 
290 		r = -EFAULT;
291 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
292 			break;
293 		n = reg_list.n;
294 		reg_list.n = kvm_riscv_vcpu_num_regs(vcpu);
295 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
296 			break;
297 		r = -E2BIG;
298 		if (n < reg_list.n)
299 			break;
300 		r = kvm_riscv_vcpu_copy_reg_indices(vcpu, user_list->reg);
301 		break;
302 	}
303 	default:
304 		break;
305 	}
306 
307 	return r;
308 }
309 
310 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
311 				  struct kvm_sregs *sregs)
312 {
313 	return -EINVAL;
314 }
315 
316 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
317 				  struct kvm_sregs *sregs)
318 {
319 	return -EINVAL;
320 }
321 
322 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
323 {
324 	return -EINVAL;
325 }
326 
327 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
328 {
329 	return -EINVAL;
330 }
331 
332 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
333 				  struct kvm_translation *tr)
334 {
335 	return -EINVAL;
336 }
337 
338 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
339 {
340 	return -EINVAL;
341 }
342 
343 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
344 {
345 	return -EINVAL;
346 }
347 
348 void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
349 {
350 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
351 	unsigned long mask, val;
352 
353 	if (READ_ONCE(vcpu->arch.irqs_pending_mask[0])) {
354 		mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[0], 0);
355 		val = READ_ONCE(vcpu->arch.irqs_pending[0]) & mask;
356 
357 		csr->hvip &= ~mask;
358 		csr->hvip |= val;
359 	}
360 
361 	/* Flush AIA high interrupts */
362 	kvm_riscv_vcpu_aia_flush_interrupts(vcpu);
363 }
364 
365 void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
366 {
367 	unsigned long hvip;
368 	struct kvm_vcpu_arch *v = &vcpu->arch;
369 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
370 
371 	/* Read current HVIP and VSIE CSRs */
372 	csr->vsie = ncsr_read(CSR_VSIE);
373 
374 	/* Sync-up HVIP.VSSIP bit changes does by Guest */
375 	hvip = ncsr_read(CSR_HVIP);
376 	if ((csr->hvip ^ hvip) & (1UL << IRQ_VS_SOFT)) {
377 		if (hvip & (1UL << IRQ_VS_SOFT)) {
378 			if (!test_and_set_bit(IRQ_VS_SOFT,
379 					      v->irqs_pending_mask))
380 				set_bit(IRQ_VS_SOFT, v->irqs_pending);
381 		} else {
382 			if (!test_and_set_bit(IRQ_VS_SOFT,
383 					      v->irqs_pending_mask))
384 				clear_bit(IRQ_VS_SOFT, v->irqs_pending);
385 		}
386 	}
387 
388 	/* Sync up the HVIP.LCOFIP bit changes (only clear) by the guest */
389 	if ((csr->hvip ^ hvip) & (1UL << IRQ_PMU_OVF)) {
390 		if (!(hvip & (1UL << IRQ_PMU_OVF)) &&
391 		    !test_and_set_bit(IRQ_PMU_OVF, v->irqs_pending_mask))
392 			clear_bit(IRQ_PMU_OVF, v->irqs_pending);
393 	}
394 
395 	/* Sync-up AIA high interrupts */
396 	kvm_riscv_vcpu_aia_sync_interrupts(vcpu);
397 
398 	/* Sync-up timer CSRs */
399 	kvm_riscv_vcpu_timer_sync(vcpu);
400 }
401 
402 int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
403 {
404 	/*
405 	 * We only allow VS-mode software, timer, and external
406 	 * interrupts when irq is one of the local interrupts
407 	 * defined by RISC-V privilege specification.
408 	 */
409 	if (irq < IRQ_LOCAL_MAX &&
410 	    irq != IRQ_VS_SOFT &&
411 	    irq != IRQ_VS_TIMER &&
412 	    irq != IRQ_VS_EXT &&
413 	    irq != IRQ_PMU_OVF)
414 		return -EINVAL;
415 
416 	set_bit(irq, vcpu->arch.irqs_pending);
417 	smp_mb__before_atomic();
418 	set_bit(irq, vcpu->arch.irqs_pending_mask);
419 
420 	kvm_vcpu_kick(vcpu);
421 
422 	return 0;
423 }
424 
425 int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
426 {
427 	/*
428 	 * We only allow VS-mode software, timer, counter overflow and external
429 	 * interrupts when irq is one of the local interrupts
430 	 * defined by RISC-V privilege specification.
431 	 */
432 	if (irq < IRQ_LOCAL_MAX &&
433 	    irq != IRQ_VS_SOFT &&
434 	    irq != IRQ_VS_TIMER &&
435 	    irq != IRQ_VS_EXT &&
436 	    irq != IRQ_PMU_OVF)
437 		return -EINVAL;
438 
439 	clear_bit(irq, vcpu->arch.irqs_pending);
440 	smp_mb__before_atomic();
441 	set_bit(irq, vcpu->arch.irqs_pending_mask);
442 
443 	return 0;
444 }
445 
446 bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, u64 mask)
447 {
448 	unsigned long ie;
449 
450 	ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
451 		<< VSIP_TO_HVIP_SHIFT) & (unsigned long)mask;
452 	ie |= vcpu->arch.guest_csr.vsie & ~IRQ_LOCAL_MASK &
453 		(unsigned long)mask;
454 	if (READ_ONCE(vcpu->arch.irqs_pending[0]) & ie)
455 		return true;
456 
457 	/* Check AIA high interrupts */
458 	return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask);
459 }
460 
461 void __kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
462 {
463 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
464 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
465 	kvm_vcpu_kick(vcpu);
466 }
467 
468 void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
469 {
470 	spin_lock(&vcpu->arch.mp_state_lock);
471 	__kvm_riscv_vcpu_power_off(vcpu);
472 	spin_unlock(&vcpu->arch.mp_state_lock);
473 }
474 
475 void __kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu)
476 {
477 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
478 	kvm_vcpu_wake_up(vcpu);
479 }
480 
481 void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu)
482 {
483 	spin_lock(&vcpu->arch.mp_state_lock);
484 	__kvm_riscv_vcpu_power_on(vcpu);
485 	spin_unlock(&vcpu->arch.mp_state_lock);
486 }
487 
488 bool kvm_riscv_vcpu_stopped(struct kvm_vcpu *vcpu)
489 {
490 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
491 }
492 
493 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
494 				    struct kvm_mp_state *mp_state)
495 {
496 	*mp_state = READ_ONCE(vcpu->arch.mp_state);
497 
498 	return 0;
499 }
500 
501 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
502 				    struct kvm_mp_state *mp_state)
503 {
504 	int ret = 0;
505 
506 	spin_lock(&vcpu->arch.mp_state_lock);
507 
508 	switch (mp_state->mp_state) {
509 	case KVM_MP_STATE_RUNNABLE:
510 		WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
511 		break;
512 	case KVM_MP_STATE_STOPPED:
513 		__kvm_riscv_vcpu_power_off(vcpu);
514 		break;
515 	case KVM_MP_STATE_INIT_RECEIVED:
516 		if (vcpu->kvm->arch.mp_state_reset)
517 			kvm_riscv_reset_vcpu(vcpu, false);
518 		else
519 			ret = -EINVAL;
520 		break;
521 	default:
522 		ret = -EINVAL;
523 	}
524 
525 	spin_unlock(&vcpu->arch.mp_state_lock);
526 
527 	return ret;
528 }
529 
530 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
531 					struct kvm_guest_debug *dbg)
532 {
533 	if (dbg->control & KVM_GUESTDBG_ENABLE) {
534 		vcpu->guest_debug = dbg->control;
535 		vcpu->arch.cfg.hedeleg &= ~BIT(EXC_BREAKPOINT);
536 	} else {
537 		vcpu->guest_debug = 0;
538 		vcpu->arch.cfg.hedeleg |= BIT(EXC_BREAKPOINT);
539 	}
540 
541 	return 0;
542 }
543 
544 static void kvm_riscv_vcpu_setup_config(struct kvm_vcpu *vcpu)
545 {
546 	const unsigned long *isa = vcpu->arch.isa;
547 	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
548 
549 	if (riscv_isa_extension_available(isa, SVPBMT))
550 		cfg->henvcfg |= ENVCFG_PBMTE;
551 
552 	if (riscv_isa_extension_available(isa, SSTC))
553 		cfg->henvcfg |= ENVCFG_STCE;
554 
555 	if (riscv_isa_extension_available(isa, ZICBOM))
556 		cfg->henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE);
557 
558 	if (riscv_isa_extension_available(isa, ZICBOZ))
559 		cfg->henvcfg |= ENVCFG_CBZE;
560 
561 	if (riscv_isa_extension_available(isa, SVADU) &&
562 	    !riscv_isa_extension_available(isa, SVADE))
563 		cfg->henvcfg |= ENVCFG_ADUE;
564 
565 	if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) {
566 		cfg->hstateen0 |= SMSTATEEN0_HSENVCFG;
567 		if (riscv_isa_extension_available(isa, SSAIA))
568 			cfg->hstateen0 |= SMSTATEEN0_AIA_IMSIC |
569 					  SMSTATEEN0_AIA |
570 					  SMSTATEEN0_AIA_ISEL;
571 		if (riscv_isa_extension_available(isa, SMSTATEEN))
572 			cfg->hstateen0 |= SMSTATEEN0_SSTATEEN0;
573 	}
574 
575 	if (vcpu->guest_debug)
576 		cfg->hedeleg &= ~BIT(EXC_BREAKPOINT);
577 }
578 
579 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
580 {
581 	void *nsh;
582 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
583 	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
584 
585 	if (kvm_riscv_nacl_sync_csr_available()) {
586 		nsh = nacl_shmem();
587 		nacl_csr_write(nsh, CSR_VSSTATUS, csr->vsstatus);
588 		nacl_csr_write(nsh, CSR_VSIE, csr->vsie);
589 		nacl_csr_write(nsh, CSR_VSTVEC, csr->vstvec);
590 		nacl_csr_write(nsh, CSR_VSSCRATCH, csr->vsscratch);
591 		nacl_csr_write(nsh, CSR_VSEPC, csr->vsepc);
592 		nacl_csr_write(nsh, CSR_VSCAUSE, csr->vscause);
593 		nacl_csr_write(nsh, CSR_VSTVAL, csr->vstval);
594 		nacl_csr_write(nsh, CSR_HEDELEG, cfg->hedeleg);
595 		nacl_csr_write(nsh, CSR_HVIP, csr->hvip);
596 		nacl_csr_write(nsh, CSR_VSATP, csr->vsatp);
597 		nacl_csr_write(nsh, CSR_HENVCFG, cfg->henvcfg);
598 		if (IS_ENABLED(CONFIG_32BIT))
599 			nacl_csr_write(nsh, CSR_HENVCFGH, cfg->henvcfg >> 32);
600 		if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) {
601 			nacl_csr_write(nsh, CSR_HSTATEEN0, cfg->hstateen0);
602 			if (IS_ENABLED(CONFIG_32BIT))
603 				nacl_csr_write(nsh, CSR_HSTATEEN0H, cfg->hstateen0 >> 32);
604 		}
605 	} else {
606 		csr_write(CSR_VSSTATUS, csr->vsstatus);
607 		csr_write(CSR_VSIE, csr->vsie);
608 		csr_write(CSR_VSTVEC, csr->vstvec);
609 		csr_write(CSR_VSSCRATCH, csr->vsscratch);
610 		csr_write(CSR_VSEPC, csr->vsepc);
611 		csr_write(CSR_VSCAUSE, csr->vscause);
612 		csr_write(CSR_VSTVAL, csr->vstval);
613 		csr_write(CSR_HEDELEG, cfg->hedeleg);
614 		csr_write(CSR_HVIP, csr->hvip);
615 		csr_write(CSR_VSATP, csr->vsatp);
616 		csr_write(CSR_HENVCFG, cfg->henvcfg);
617 		if (IS_ENABLED(CONFIG_32BIT))
618 			csr_write(CSR_HENVCFGH, cfg->henvcfg >> 32);
619 		if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) {
620 			csr_write(CSR_HSTATEEN0, cfg->hstateen0);
621 			if (IS_ENABLED(CONFIG_32BIT))
622 				csr_write(CSR_HSTATEEN0H, cfg->hstateen0 >> 32);
623 		}
624 	}
625 
626 	kvm_riscv_mmu_update_hgatp(vcpu);
627 
628 	kvm_riscv_vcpu_timer_restore(vcpu);
629 
630 	kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context);
631 	kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
632 					vcpu->arch.isa);
633 	kvm_riscv_vcpu_host_vector_save(&vcpu->arch.host_context);
634 	kvm_riscv_vcpu_guest_vector_restore(&vcpu->arch.guest_context,
635 					    vcpu->arch.isa);
636 
637 	kvm_riscv_vcpu_aia_load(vcpu, cpu);
638 
639 	kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu);
640 
641 	vcpu->cpu = cpu;
642 }
643 
644 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
645 {
646 	void *nsh;
647 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
648 
649 	vcpu->cpu = -1;
650 
651 	kvm_riscv_vcpu_aia_put(vcpu);
652 
653 	kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
654 				     vcpu->arch.isa);
655 	kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
656 
657 	kvm_riscv_vcpu_timer_save(vcpu);
658 	kvm_riscv_vcpu_guest_vector_save(&vcpu->arch.guest_context,
659 					 vcpu->arch.isa);
660 	kvm_riscv_vcpu_host_vector_restore(&vcpu->arch.host_context);
661 
662 	if (kvm_riscv_nacl_available()) {
663 		nsh = nacl_shmem();
664 		csr->vsstatus = nacl_csr_read(nsh, CSR_VSSTATUS);
665 		csr->vsie = nacl_csr_read(nsh, CSR_VSIE);
666 		csr->vstvec = nacl_csr_read(nsh, CSR_VSTVEC);
667 		csr->vsscratch = nacl_csr_read(nsh, CSR_VSSCRATCH);
668 		csr->vsepc = nacl_csr_read(nsh, CSR_VSEPC);
669 		csr->vscause = nacl_csr_read(nsh, CSR_VSCAUSE);
670 		csr->vstval = nacl_csr_read(nsh, CSR_VSTVAL);
671 		csr->hvip = nacl_csr_read(nsh, CSR_HVIP);
672 		csr->vsatp = nacl_csr_read(nsh, CSR_VSATP);
673 	} else {
674 		csr->vsstatus = csr_read(CSR_VSSTATUS);
675 		csr->vsie = csr_read(CSR_VSIE);
676 		csr->vstvec = csr_read(CSR_VSTVEC);
677 		csr->vsscratch = csr_read(CSR_VSSCRATCH);
678 		csr->vsepc = csr_read(CSR_VSEPC);
679 		csr->vscause = csr_read(CSR_VSCAUSE);
680 		csr->vstval = csr_read(CSR_VSTVAL);
681 		csr->hvip = csr_read(CSR_HVIP);
682 		csr->vsatp = csr_read(CSR_VSATP);
683 	}
684 }
685 
686 /**
687  * kvm_riscv_check_vcpu_requests - check and handle pending vCPU requests
688  * @vcpu:	the VCPU pointer
689  *
690  * Return: 1 if we should enter the guest
691  *	    0 if we should exit to userspace
692  */
693 static int kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu)
694 {
695 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
696 
697 	if (kvm_request_pending(vcpu)) {
698 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) {
699 			kvm_vcpu_srcu_read_unlock(vcpu);
700 			rcuwait_wait_event(wait,
701 				(!kvm_riscv_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
702 				TASK_INTERRUPTIBLE);
703 			kvm_vcpu_srcu_read_lock(vcpu);
704 
705 			if (kvm_riscv_vcpu_stopped(vcpu) || vcpu->arch.pause) {
706 				/*
707 				 * Awaken to handle a signal, request to
708 				 * sleep again later.
709 				 */
710 				kvm_make_request(KVM_REQ_SLEEP, vcpu);
711 			}
712 		}
713 
714 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
715 			kvm_riscv_reset_vcpu(vcpu, true);
716 
717 		if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu))
718 			kvm_riscv_mmu_update_hgatp(vcpu);
719 
720 		if (kvm_check_request(KVM_REQ_FENCE_I, vcpu))
721 			kvm_riscv_fence_i_process(vcpu);
722 
723 		if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
724 			kvm_riscv_tlb_flush_process(vcpu);
725 
726 		if (kvm_check_request(KVM_REQ_HFENCE_VVMA_ALL, vcpu))
727 			kvm_riscv_hfence_vvma_all_process(vcpu);
728 
729 		if (kvm_check_request(KVM_REQ_HFENCE, vcpu))
730 			kvm_riscv_hfence_process(vcpu);
731 
732 		if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu))
733 			kvm_riscv_vcpu_record_steal_time(vcpu);
734 
735 		if (kvm_dirty_ring_check_request(vcpu))
736 			return 0;
737 	}
738 
739 	return 1;
740 }
741 
742 static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
743 {
744 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
745 
746 	ncsr_write(CSR_HVIP, csr->hvip);
747 	kvm_riscv_vcpu_aia_update_hvip(vcpu);
748 }
749 
750 static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu *vcpu)
751 {
752 	struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr;
753 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
754 	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
755 
756 	vcpu->arch.host_scounteren = csr_swap(CSR_SCOUNTEREN, csr->scounteren);
757 	vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg);
758 	if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) &&
759 	    (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0))
760 		vcpu->arch.host_sstateen0 = csr_swap(CSR_SSTATEEN0,
761 						     smcsr->sstateen0);
762 }
763 
764 static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *vcpu)
765 {
766 	struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr;
767 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
768 	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
769 
770 	csr->scounteren = csr_swap(CSR_SCOUNTEREN, vcpu->arch.host_scounteren);
771 	csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg);
772 	if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) &&
773 	    (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0))
774 		smcsr->sstateen0 = csr_swap(CSR_SSTATEEN0,
775 					    vcpu->arch.host_sstateen0);
776 }
777 
778 /*
779  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
780  * the vCPU is running.
781  *
782  * This must be noinstr as instrumentation may make use of RCU, and this is not
783  * safe during the EQS.
784  */
785 static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu,
786 					      struct kvm_cpu_trap *trap)
787 {
788 	void *nsh;
789 	struct kvm_cpu_context *gcntx = &vcpu->arch.guest_context;
790 	struct kvm_cpu_context *hcntx = &vcpu->arch.host_context;
791 
792 	/*
793 	 * We save trap CSRs (such as SEPC, SCAUSE, STVAL, HTVAL, and
794 	 * HTINST) here because we do local_irq_enable() after this
795 	 * function in kvm_arch_vcpu_ioctl_run() which can result in
796 	 * an interrupt immediately after local_irq_enable() and can
797 	 * potentially change trap CSRs.
798 	 */
799 
800 	kvm_riscv_vcpu_swap_in_guest_state(vcpu);
801 	guest_state_enter_irqoff();
802 
803 	if (kvm_riscv_nacl_sync_sret_available()) {
804 		nsh = nacl_shmem();
805 
806 		if (kvm_riscv_nacl_autoswap_csr_available()) {
807 			hcntx->hstatus =
808 				nacl_csr_read(nsh, CSR_HSTATUS);
809 			nacl_scratch_write_long(nsh,
810 						SBI_NACL_SHMEM_AUTOSWAP_OFFSET +
811 						SBI_NACL_SHMEM_AUTOSWAP_HSTATUS,
812 						gcntx->hstatus);
813 			nacl_scratch_write_long(nsh,
814 						SBI_NACL_SHMEM_AUTOSWAP_OFFSET,
815 						SBI_NACL_SHMEM_AUTOSWAP_FLAG_HSTATUS);
816 		} else if (kvm_riscv_nacl_sync_csr_available()) {
817 			hcntx->hstatus = nacl_csr_swap(nsh,
818 						       CSR_HSTATUS, gcntx->hstatus);
819 		} else {
820 			hcntx->hstatus = csr_swap(CSR_HSTATUS, gcntx->hstatus);
821 		}
822 
823 		nacl_scratch_write_longs(nsh,
824 					 SBI_NACL_SHMEM_SRET_OFFSET +
825 					 SBI_NACL_SHMEM_SRET_X(1),
826 					 &gcntx->ra,
827 					 SBI_NACL_SHMEM_SRET_X_LAST);
828 
829 		__kvm_riscv_nacl_switch_to(&vcpu->arch, SBI_EXT_NACL,
830 					   SBI_EXT_NACL_SYNC_SRET);
831 
832 		if (kvm_riscv_nacl_autoswap_csr_available()) {
833 			nacl_scratch_write_long(nsh,
834 						SBI_NACL_SHMEM_AUTOSWAP_OFFSET,
835 						0);
836 			gcntx->hstatus = nacl_scratch_read_long(nsh,
837 								SBI_NACL_SHMEM_AUTOSWAP_OFFSET +
838 								SBI_NACL_SHMEM_AUTOSWAP_HSTATUS);
839 		} else {
840 			gcntx->hstatus = csr_swap(CSR_HSTATUS, hcntx->hstatus);
841 		}
842 
843 		trap->htval = nacl_csr_read(nsh, CSR_HTVAL);
844 		trap->htinst = nacl_csr_read(nsh, CSR_HTINST);
845 	} else {
846 		hcntx->hstatus = csr_swap(CSR_HSTATUS, gcntx->hstatus);
847 
848 		__kvm_riscv_switch_to(&vcpu->arch);
849 
850 		gcntx->hstatus = csr_swap(CSR_HSTATUS, hcntx->hstatus);
851 
852 		trap->htval = csr_read(CSR_HTVAL);
853 		trap->htinst = csr_read(CSR_HTINST);
854 	}
855 
856 	trap->sepc = gcntx->sepc;
857 	trap->scause = csr_read(CSR_SCAUSE);
858 	trap->stval = csr_read(CSR_STVAL);
859 
860 	vcpu->arch.last_exit_cpu = vcpu->cpu;
861 	guest_state_exit_irqoff();
862 	kvm_riscv_vcpu_swap_in_host_state(vcpu);
863 }
864 
865 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
866 {
867 	int ret;
868 	struct kvm_cpu_trap trap;
869 	struct kvm_run *run = vcpu->run;
870 
871 	if (!vcpu->arch.ran_atleast_once)
872 		kvm_riscv_vcpu_setup_config(vcpu);
873 
874 	/* Mark this VCPU ran at least once */
875 	vcpu->arch.ran_atleast_once = true;
876 
877 	kvm_vcpu_srcu_read_lock(vcpu);
878 
879 	switch (run->exit_reason) {
880 	case KVM_EXIT_MMIO:
881 		/* Process MMIO value returned from user-space */
882 		ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run);
883 		break;
884 	case KVM_EXIT_RISCV_SBI:
885 		/* Process SBI value returned from user-space */
886 		ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run);
887 		break;
888 	case KVM_EXIT_RISCV_CSR:
889 		/* Process CSR value returned from user-space */
890 		ret = kvm_riscv_vcpu_csr_return(vcpu, vcpu->run);
891 		break;
892 	default:
893 		ret = 0;
894 		break;
895 	}
896 	if (ret) {
897 		kvm_vcpu_srcu_read_unlock(vcpu);
898 		return ret;
899 	}
900 
901 	if (!vcpu->wants_to_run) {
902 		kvm_vcpu_srcu_read_unlock(vcpu);
903 		return -EINTR;
904 	}
905 
906 	vcpu_load(vcpu);
907 
908 	kvm_sigset_activate(vcpu);
909 
910 	ret = 1;
911 	run->exit_reason = KVM_EXIT_UNKNOWN;
912 	while (ret > 0) {
913 		/* Check conditions before entering the guest */
914 		ret = xfer_to_guest_mode_handle_work(vcpu);
915 		if (ret)
916 			continue;
917 		ret = 1;
918 
919 		kvm_riscv_gstage_vmid_update(vcpu);
920 
921 		ret = kvm_riscv_check_vcpu_requests(vcpu);
922 		if (ret <= 0)
923 			continue;
924 
925 		preempt_disable();
926 
927 		/* Update AIA HW state before entering guest */
928 		ret = kvm_riscv_vcpu_aia_update(vcpu);
929 		if (ret <= 0) {
930 			preempt_enable();
931 			continue;
932 		}
933 
934 		local_irq_disable();
935 
936 		/*
937 		 * Ensure we set mode to IN_GUEST_MODE after we disable
938 		 * interrupts and before the final VCPU requests check.
939 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
940 		 * Documentation/virt/kvm/vcpu-requests.rst
941 		 */
942 		vcpu->mode = IN_GUEST_MODE;
943 
944 		kvm_vcpu_srcu_read_unlock(vcpu);
945 		smp_mb__after_srcu_read_unlock();
946 
947 		/*
948 		 * We might have got VCPU interrupts updated asynchronously
949 		 * so update it in HW.
950 		 */
951 		kvm_riscv_vcpu_flush_interrupts(vcpu);
952 
953 		/* Update HVIP CSR for current CPU */
954 		kvm_riscv_update_hvip(vcpu);
955 
956 		if (kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) ||
957 		    kvm_request_pending(vcpu) ||
958 		    xfer_to_guest_mode_work_pending()) {
959 			vcpu->mode = OUTSIDE_GUEST_MODE;
960 			local_irq_enable();
961 			preempt_enable();
962 			kvm_vcpu_srcu_read_lock(vcpu);
963 			continue;
964 		}
965 
966 		/*
967 		 * Sanitize VMID mappings cached (TLB) on current CPU
968 		 *
969 		 * Note: This should be done after G-stage VMID has been
970 		 * updated using kvm_riscv_gstage_vmid_ver_changed()
971 		 */
972 		kvm_riscv_gstage_vmid_sanitize(vcpu);
973 
974 		trace_kvm_entry(vcpu);
975 
976 		guest_timing_enter_irqoff();
977 
978 		kvm_riscv_vcpu_enter_exit(vcpu, &trap);
979 
980 		vcpu->mode = OUTSIDE_GUEST_MODE;
981 		vcpu->stat.exits++;
982 
983 		/* Syncup interrupts state with HW */
984 		kvm_riscv_vcpu_sync_interrupts(vcpu);
985 
986 		/*
987 		 * We must ensure that any pending interrupts are taken before
988 		 * we exit guest timing so that timer ticks are accounted as
989 		 * guest time. Transiently unmask interrupts so that any
990 		 * pending interrupts are taken.
991 		 *
992 		 * There's no barrier which ensures that pending interrupts are
993 		 * recognised, so we just hope that the CPU takes any pending
994 		 * interrupts between the enable and disable.
995 		 */
996 		local_irq_enable();
997 		local_irq_disable();
998 
999 		guest_timing_exit_irqoff();
1000 
1001 		local_irq_enable();
1002 
1003 		trace_kvm_exit(&trap);
1004 
1005 		preempt_enable();
1006 
1007 		kvm_vcpu_srcu_read_lock(vcpu);
1008 
1009 		ret = kvm_riscv_vcpu_exit(vcpu, run, &trap);
1010 	}
1011 
1012 	kvm_sigset_deactivate(vcpu);
1013 
1014 	vcpu_put(vcpu);
1015 
1016 	kvm_vcpu_srcu_read_unlock(vcpu);
1017 
1018 	return ret;
1019 }
1020