xref: /openbmc/linux/arch/riscv/kvm/vcpu.c (revision 52ec4b695dbe0552bb994c4149e9122610a76668)
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/uaccess.h>
17 #include <linux/vmalloc.h>
18 #include <linux/sched/signal.h>
19 #include <linux/fs.h>
20 #include <linux/kvm_host.h>
21 #include <asm/csr.h>
22 #include <asm/cacheflush.h>
23 #include <asm/hwcap.h>
24 #include <asm/sbi.h>
25 
26 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
27 	KVM_GENERIC_VCPU_STATS(),
28 	STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
29 	STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
30 	STATS_DESC_COUNTER(VCPU, mmio_exit_user),
31 	STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
32 	STATS_DESC_COUNTER(VCPU, csr_exit_user),
33 	STATS_DESC_COUNTER(VCPU, csr_exit_kernel),
34 	STATS_DESC_COUNTER(VCPU, signal_exits),
35 	STATS_DESC_COUNTER(VCPU, exits)
36 };
37 
38 const struct kvm_stats_header kvm_vcpu_stats_header = {
39 	.name_size = KVM_STATS_NAME_SIZE,
40 	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
41 	.id_offset = sizeof(struct kvm_stats_header),
42 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
43 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
44 		       sizeof(kvm_vcpu_stats_desc),
45 };
46 
47 #define KVM_RISCV_BASE_ISA_MASK		GENMASK(25, 0)
48 
49 #define KVM_ISA_EXT_ARR(ext)		[KVM_RISCV_ISA_EXT_##ext] = RISCV_ISA_EXT_##ext
50 
51 /* Mapping between KVM ISA Extension ID & Host ISA extension ID */
52 static const unsigned long kvm_isa_ext_arr[] = {
53 	[KVM_RISCV_ISA_EXT_A] = RISCV_ISA_EXT_a,
54 	[KVM_RISCV_ISA_EXT_C] = RISCV_ISA_EXT_c,
55 	[KVM_RISCV_ISA_EXT_D] = RISCV_ISA_EXT_d,
56 	[KVM_RISCV_ISA_EXT_F] = RISCV_ISA_EXT_f,
57 	[KVM_RISCV_ISA_EXT_H] = RISCV_ISA_EXT_h,
58 	[KVM_RISCV_ISA_EXT_I] = RISCV_ISA_EXT_i,
59 	[KVM_RISCV_ISA_EXT_M] = RISCV_ISA_EXT_m,
60 
61 	KVM_ISA_EXT_ARR(SSTC),
62 	KVM_ISA_EXT_ARR(SVINVAL),
63 	KVM_ISA_EXT_ARR(SVPBMT),
64 	KVM_ISA_EXT_ARR(ZIHINTPAUSE),
65 	KVM_ISA_EXT_ARR(ZICBOM),
66 };
67 
68 static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext)
69 {
70 	unsigned long i;
71 
72 	for (i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) {
73 		if (kvm_isa_ext_arr[i] == base_ext)
74 			return i;
75 	}
76 
77 	return KVM_RISCV_ISA_EXT_MAX;
78 }
79 
80 static bool kvm_riscv_vcpu_isa_enable_allowed(unsigned long ext)
81 {
82 	switch (ext) {
83 	case KVM_RISCV_ISA_EXT_H:
84 		return false;
85 	default:
86 		break;
87 	}
88 
89 	return true;
90 }
91 
92 static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
93 {
94 	switch (ext) {
95 	case KVM_RISCV_ISA_EXT_A:
96 	case KVM_RISCV_ISA_EXT_C:
97 	case KVM_RISCV_ISA_EXT_I:
98 	case KVM_RISCV_ISA_EXT_M:
99 	case KVM_RISCV_ISA_EXT_SSTC:
100 	case KVM_RISCV_ISA_EXT_SVINVAL:
101 	case KVM_RISCV_ISA_EXT_ZIHINTPAUSE:
102 		return false;
103 	default:
104 		break;
105 	}
106 
107 	return true;
108 }
109 
110 static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
111 {
112 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
113 	struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
114 	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
115 	struct kvm_cpu_context *reset_cntx = &vcpu->arch.guest_reset_context;
116 	bool loaded;
117 
118 	/**
119 	 * The preemption should be disabled here because it races with
120 	 * kvm_sched_out/kvm_sched_in(called from preempt notifiers) which
121 	 * also calls vcpu_load/put.
122 	 */
123 	get_cpu();
124 	loaded = (vcpu->cpu != -1);
125 	if (loaded)
126 		kvm_arch_vcpu_put(vcpu);
127 
128 	vcpu->arch.last_exit_cpu = -1;
129 
130 	memcpy(csr, reset_csr, sizeof(*csr));
131 
132 	memcpy(cntx, reset_cntx, sizeof(*cntx));
133 
134 	kvm_riscv_vcpu_fp_reset(vcpu);
135 
136 	kvm_riscv_vcpu_timer_reset(vcpu);
137 
138 	WRITE_ONCE(vcpu->arch.irqs_pending, 0);
139 	WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
140 
141 	vcpu->arch.hfence_head = 0;
142 	vcpu->arch.hfence_tail = 0;
143 	memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue));
144 
145 	/* Reset the guest CSRs for hotplug usecase */
146 	if (loaded)
147 		kvm_arch_vcpu_load(vcpu, smp_processor_id());
148 	put_cpu();
149 }
150 
151 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
152 {
153 	return 0;
154 }
155 
156 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
157 {
158 	struct kvm_cpu_context *cntx;
159 	struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
160 	unsigned long host_isa, i;
161 
162 	/* Mark this VCPU never ran */
163 	vcpu->arch.ran_atleast_once = false;
164 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
165 	bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX);
166 
167 	/* Setup ISA features available to VCPU */
168 	for (i = 0; i < ARRAY_SIZE(kvm_isa_ext_arr); i++) {
169 		host_isa = kvm_isa_ext_arr[i];
170 		if (__riscv_isa_extension_available(NULL, host_isa) &&
171 		    kvm_riscv_vcpu_isa_enable_allowed(i))
172 			set_bit(host_isa, vcpu->arch.isa);
173 	}
174 
175 	/* Setup vendor, arch, and implementation details */
176 	vcpu->arch.mvendorid = sbi_get_mvendorid();
177 	vcpu->arch.marchid = sbi_get_marchid();
178 	vcpu->arch.mimpid = sbi_get_mimpid();
179 
180 	/* Setup VCPU hfence queue */
181 	spin_lock_init(&vcpu->arch.hfence_lock);
182 
183 	/* Setup reset state of shadow SSTATUS and HSTATUS CSRs */
184 	cntx = &vcpu->arch.guest_reset_context;
185 	cntx->sstatus = SR_SPP | SR_SPIE;
186 	cntx->hstatus = 0;
187 	cntx->hstatus |= HSTATUS_VTW;
188 	cntx->hstatus |= HSTATUS_SPVP;
189 	cntx->hstatus |= HSTATUS_SPV;
190 
191 	/* By default, make CY, TM, and IR counters accessible in VU mode */
192 	reset_csr->scounteren = 0x7;
193 
194 	/* Setup VCPU timer */
195 	kvm_riscv_vcpu_timer_init(vcpu);
196 
197 	/* Reset VCPU */
198 	kvm_riscv_reset_vcpu(vcpu);
199 
200 	return 0;
201 }
202 
203 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
204 {
205 	/**
206 	 * vcpu with id 0 is the designated boot cpu.
207 	 * Keep all vcpus with non-zero id in power-off state so that
208 	 * they can be brought up using SBI HSM extension.
209 	 */
210 	if (vcpu->vcpu_idx != 0)
211 		kvm_riscv_vcpu_power_off(vcpu);
212 }
213 
214 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
215 {
216 	/* Cleanup VCPU timer */
217 	kvm_riscv_vcpu_timer_deinit(vcpu);
218 
219 	/* Free unused pages pre-allocated for G-stage page table mappings */
220 	kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
221 }
222 
223 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
224 {
225 	return kvm_riscv_vcpu_timer_pending(vcpu);
226 }
227 
228 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
229 {
230 }
231 
232 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
233 {
234 }
235 
236 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
237 {
238 	return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) &&
239 		!vcpu->arch.power_off && !vcpu->arch.pause);
240 }
241 
242 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
243 {
244 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
245 }
246 
247 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
248 {
249 	return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false;
250 }
251 
252 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
253 {
254 	return VM_FAULT_SIGBUS;
255 }
256 
257 static int kvm_riscv_vcpu_get_reg_config(struct kvm_vcpu *vcpu,
258 					 const struct kvm_one_reg *reg)
259 {
260 	unsigned long __user *uaddr =
261 			(unsigned long __user *)(unsigned long)reg->addr;
262 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
263 					    KVM_REG_SIZE_MASK |
264 					    KVM_REG_RISCV_CONFIG);
265 	unsigned long reg_val;
266 
267 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
268 		return -EINVAL;
269 
270 	switch (reg_num) {
271 	case KVM_REG_RISCV_CONFIG_REG(isa):
272 		reg_val = vcpu->arch.isa[0] & KVM_RISCV_BASE_ISA_MASK;
273 		break;
274 	case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size):
275 		if (!riscv_isa_extension_available(vcpu->arch.isa, ZICBOM))
276 			return -EINVAL;
277 		reg_val = riscv_cbom_block_size;
278 		break;
279 	default:
280 		return -EINVAL;
281 	}
282 
283 	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
284 		return -EFAULT;
285 
286 	return 0;
287 }
288 
289 static int kvm_riscv_vcpu_set_reg_config(struct kvm_vcpu *vcpu,
290 					 const struct kvm_one_reg *reg)
291 {
292 	unsigned long __user *uaddr =
293 			(unsigned long __user *)(unsigned long)reg->addr;
294 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
295 					    KVM_REG_SIZE_MASK |
296 					    KVM_REG_RISCV_CONFIG);
297 	unsigned long i, isa_ext, reg_val;
298 
299 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
300 		return -EINVAL;
301 
302 	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
303 		return -EFAULT;
304 
305 	switch (reg_num) {
306 	case KVM_REG_RISCV_CONFIG_REG(isa):
307 		/*
308 		 * This ONE REG interface is only defined for
309 		 * single letter extensions.
310 		 */
311 		if (fls(reg_val) >= RISCV_ISA_EXT_BASE)
312 			return -EINVAL;
313 
314 		if (!vcpu->arch.ran_atleast_once) {
315 			/* Ignore the enable/disable request for certain extensions */
316 			for (i = 0; i < RISCV_ISA_EXT_BASE; i++) {
317 				isa_ext = kvm_riscv_vcpu_base2isa_ext(i);
318 				if (isa_ext >= KVM_RISCV_ISA_EXT_MAX) {
319 					reg_val &= ~BIT(i);
320 					continue;
321 				}
322 				if (!kvm_riscv_vcpu_isa_enable_allowed(isa_ext))
323 					if (reg_val & BIT(i))
324 						reg_val &= ~BIT(i);
325 				if (!kvm_riscv_vcpu_isa_disable_allowed(isa_ext))
326 					if (!(reg_val & BIT(i)))
327 						reg_val |= BIT(i);
328 			}
329 			reg_val &= riscv_isa_extension_base(NULL);
330 			/* Do not modify anything beyond single letter extensions */
331 			reg_val = (vcpu->arch.isa[0] & ~KVM_RISCV_BASE_ISA_MASK) |
332 				  (reg_val & KVM_RISCV_BASE_ISA_MASK);
333 			vcpu->arch.isa[0] = reg_val;
334 			kvm_riscv_vcpu_fp_reset(vcpu);
335 		} else {
336 			return -EOPNOTSUPP;
337 		}
338 		break;
339 	case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size):
340 		return -EOPNOTSUPP;
341 	default:
342 		return -EINVAL;
343 	}
344 
345 	return 0;
346 }
347 
348 static int kvm_riscv_vcpu_get_reg_core(struct kvm_vcpu *vcpu,
349 				       const struct kvm_one_reg *reg)
350 {
351 	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
352 	unsigned long __user *uaddr =
353 			(unsigned long __user *)(unsigned long)reg->addr;
354 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
355 					    KVM_REG_SIZE_MASK |
356 					    KVM_REG_RISCV_CORE);
357 	unsigned long reg_val;
358 
359 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
360 		return -EINVAL;
361 	if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
362 		return -EINVAL;
363 
364 	if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
365 		reg_val = cntx->sepc;
366 	else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
367 		 reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
368 		reg_val = ((unsigned long *)cntx)[reg_num];
369 	else if (reg_num == KVM_REG_RISCV_CORE_REG(mode))
370 		reg_val = (cntx->sstatus & SR_SPP) ?
371 				KVM_RISCV_MODE_S : KVM_RISCV_MODE_U;
372 	else
373 		return -EINVAL;
374 
375 	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
376 		return -EFAULT;
377 
378 	return 0;
379 }
380 
381 static int kvm_riscv_vcpu_set_reg_core(struct kvm_vcpu *vcpu,
382 				       const struct kvm_one_reg *reg)
383 {
384 	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
385 	unsigned long __user *uaddr =
386 			(unsigned long __user *)(unsigned long)reg->addr;
387 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
388 					    KVM_REG_SIZE_MASK |
389 					    KVM_REG_RISCV_CORE);
390 	unsigned long reg_val;
391 
392 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
393 		return -EINVAL;
394 	if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
395 		return -EINVAL;
396 
397 	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
398 		return -EFAULT;
399 
400 	if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
401 		cntx->sepc = reg_val;
402 	else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
403 		 reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
404 		((unsigned long *)cntx)[reg_num] = reg_val;
405 	else if (reg_num == KVM_REG_RISCV_CORE_REG(mode)) {
406 		if (reg_val == KVM_RISCV_MODE_S)
407 			cntx->sstatus |= SR_SPP;
408 		else
409 			cntx->sstatus &= ~SR_SPP;
410 	} else
411 		return -EINVAL;
412 
413 	return 0;
414 }
415 
416 static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu,
417 				      const struct kvm_one_reg *reg)
418 {
419 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
420 	unsigned long __user *uaddr =
421 			(unsigned long __user *)(unsigned long)reg->addr;
422 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
423 					    KVM_REG_SIZE_MASK |
424 					    KVM_REG_RISCV_CSR);
425 	unsigned long reg_val;
426 
427 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
428 		return -EINVAL;
429 	if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
430 		return -EINVAL;
431 
432 	if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) {
433 		kvm_riscv_vcpu_flush_interrupts(vcpu);
434 		reg_val = (csr->hvip >> VSIP_TO_HVIP_SHIFT) & VSIP_VALID_MASK;
435 	} else
436 		reg_val = ((unsigned long *)csr)[reg_num];
437 
438 	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
439 		return -EFAULT;
440 
441 	return 0;
442 }
443 
444 static int kvm_riscv_vcpu_set_reg_csr(struct kvm_vcpu *vcpu,
445 				      const struct kvm_one_reg *reg)
446 {
447 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
448 	unsigned long __user *uaddr =
449 			(unsigned long __user *)(unsigned long)reg->addr;
450 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
451 					    KVM_REG_SIZE_MASK |
452 					    KVM_REG_RISCV_CSR);
453 	unsigned long reg_val;
454 
455 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
456 		return -EINVAL;
457 	if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
458 		return -EINVAL;
459 
460 	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
461 		return -EFAULT;
462 
463 	if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) {
464 		reg_val &= VSIP_VALID_MASK;
465 		reg_val <<= VSIP_TO_HVIP_SHIFT;
466 	}
467 
468 	((unsigned long *)csr)[reg_num] = reg_val;
469 
470 	if (reg_num == KVM_REG_RISCV_CSR_REG(sip))
471 		WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
472 
473 	return 0;
474 }
475 
476 static int kvm_riscv_vcpu_get_reg_isa_ext(struct kvm_vcpu *vcpu,
477 					  const struct kvm_one_reg *reg)
478 {
479 	unsigned long __user *uaddr =
480 			(unsigned long __user *)(unsigned long)reg->addr;
481 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
482 					    KVM_REG_SIZE_MASK |
483 					    KVM_REG_RISCV_ISA_EXT);
484 	unsigned long reg_val = 0;
485 	unsigned long host_isa_ext;
486 
487 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
488 		return -EINVAL;
489 
490 	if (reg_num >= KVM_RISCV_ISA_EXT_MAX ||
491 	    reg_num >= ARRAY_SIZE(kvm_isa_ext_arr))
492 		return -EINVAL;
493 
494 	host_isa_ext = kvm_isa_ext_arr[reg_num];
495 	if (__riscv_isa_extension_available(vcpu->arch.isa, host_isa_ext))
496 		reg_val = 1; /* Mark the given extension as available */
497 
498 	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
499 		return -EFAULT;
500 
501 	return 0;
502 }
503 
504 static int kvm_riscv_vcpu_set_reg_isa_ext(struct kvm_vcpu *vcpu,
505 					  const struct kvm_one_reg *reg)
506 {
507 	unsigned long __user *uaddr =
508 			(unsigned long __user *)(unsigned long)reg->addr;
509 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
510 					    KVM_REG_SIZE_MASK |
511 					    KVM_REG_RISCV_ISA_EXT);
512 	unsigned long reg_val;
513 	unsigned long host_isa_ext;
514 
515 	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
516 		return -EINVAL;
517 
518 	if (reg_num >= KVM_RISCV_ISA_EXT_MAX ||
519 	    reg_num >= ARRAY_SIZE(kvm_isa_ext_arr))
520 		return -EINVAL;
521 
522 	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
523 		return -EFAULT;
524 
525 	host_isa_ext = kvm_isa_ext_arr[reg_num];
526 	if (!__riscv_isa_extension_available(NULL, host_isa_ext))
527 		return	-EOPNOTSUPP;
528 
529 	if (!vcpu->arch.ran_atleast_once) {
530 		/*
531 		 * All multi-letter extension and a few single letter
532 		 * extension can be disabled
533 		 */
534 		if (reg_val == 1 &&
535 		    kvm_riscv_vcpu_isa_enable_allowed(reg_num))
536 			set_bit(host_isa_ext, vcpu->arch.isa);
537 		else if (!reg_val &&
538 			 kvm_riscv_vcpu_isa_disable_allowed(reg_num))
539 			clear_bit(host_isa_ext, vcpu->arch.isa);
540 		else
541 			return -EINVAL;
542 		kvm_riscv_vcpu_fp_reset(vcpu);
543 	} else {
544 		return -EOPNOTSUPP;
545 	}
546 
547 	return 0;
548 }
549 
550 static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu,
551 				  const struct kvm_one_reg *reg)
552 {
553 	switch (reg->id & KVM_REG_RISCV_TYPE_MASK) {
554 	case KVM_REG_RISCV_CONFIG:
555 		return kvm_riscv_vcpu_set_reg_config(vcpu, reg);
556 	case KVM_REG_RISCV_CORE:
557 		return kvm_riscv_vcpu_set_reg_core(vcpu, reg);
558 	case KVM_REG_RISCV_CSR:
559 		return kvm_riscv_vcpu_set_reg_csr(vcpu, reg);
560 	case KVM_REG_RISCV_TIMER:
561 		return kvm_riscv_vcpu_set_reg_timer(vcpu, reg);
562 	case KVM_REG_RISCV_FP_F:
563 		return kvm_riscv_vcpu_set_reg_fp(vcpu, reg,
564 						 KVM_REG_RISCV_FP_F);
565 	case KVM_REG_RISCV_FP_D:
566 		return kvm_riscv_vcpu_set_reg_fp(vcpu, reg,
567 						 KVM_REG_RISCV_FP_D);
568 	case KVM_REG_RISCV_ISA_EXT:
569 		return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg);
570 	default:
571 		break;
572 	}
573 
574 	return -EINVAL;
575 }
576 
577 static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu,
578 				  const struct kvm_one_reg *reg)
579 {
580 	switch (reg->id & KVM_REG_RISCV_TYPE_MASK) {
581 	case KVM_REG_RISCV_CONFIG:
582 		return kvm_riscv_vcpu_get_reg_config(vcpu, reg);
583 	case KVM_REG_RISCV_CORE:
584 		return kvm_riscv_vcpu_get_reg_core(vcpu, reg);
585 	case KVM_REG_RISCV_CSR:
586 		return kvm_riscv_vcpu_get_reg_csr(vcpu, reg);
587 	case KVM_REG_RISCV_TIMER:
588 		return kvm_riscv_vcpu_get_reg_timer(vcpu, reg);
589 	case KVM_REG_RISCV_FP_F:
590 		return kvm_riscv_vcpu_get_reg_fp(vcpu, reg,
591 						 KVM_REG_RISCV_FP_F);
592 	case KVM_REG_RISCV_FP_D:
593 		return kvm_riscv_vcpu_get_reg_fp(vcpu, reg,
594 						 KVM_REG_RISCV_FP_D);
595 	case KVM_REG_RISCV_ISA_EXT:
596 		return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg);
597 	default:
598 		break;
599 	}
600 
601 	return -EINVAL;
602 }
603 
604 long kvm_arch_vcpu_async_ioctl(struct file *filp,
605 			       unsigned int ioctl, unsigned long arg)
606 {
607 	struct kvm_vcpu *vcpu = filp->private_data;
608 	void __user *argp = (void __user *)arg;
609 
610 	if (ioctl == KVM_INTERRUPT) {
611 		struct kvm_interrupt irq;
612 
613 		if (copy_from_user(&irq, argp, sizeof(irq)))
614 			return -EFAULT;
615 
616 		if (irq.irq == KVM_INTERRUPT_SET)
617 			return kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT);
618 		else
619 			return kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
620 	}
621 
622 	return -ENOIOCTLCMD;
623 }
624 
625 long kvm_arch_vcpu_ioctl(struct file *filp,
626 			 unsigned int ioctl, unsigned long arg)
627 {
628 	struct kvm_vcpu *vcpu = filp->private_data;
629 	void __user *argp = (void __user *)arg;
630 	long r = -EINVAL;
631 
632 	switch (ioctl) {
633 	case KVM_SET_ONE_REG:
634 	case KVM_GET_ONE_REG: {
635 		struct kvm_one_reg reg;
636 
637 		r = -EFAULT;
638 		if (copy_from_user(&reg, argp, sizeof(reg)))
639 			break;
640 
641 		if (ioctl == KVM_SET_ONE_REG)
642 			r = kvm_riscv_vcpu_set_reg(vcpu, &reg);
643 		else
644 			r = kvm_riscv_vcpu_get_reg(vcpu, &reg);
645 		break;
646 	}
647 	default:
648 		break;
649 	}
650 
651 	return r;
652 }
653 
654 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
655 				  struct kvm_sregs *sregs)
656 {
657 	return -EINVAL;
658 }
659 
660 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
661 				  struct kvm_sregs *sregs)
662 {
663 	return -EINVAL;
664 }
665 
666 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
667 {
668 	return -EINVAL;
669 }
670 
671 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
672 {
673 	return -EINVAL;
674 }
675 
676 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
677 				  struct kvm_translation *tr)
678 {
679 	return -EINVAL;
680 }
681 
682 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
683 {
684 	return -EINVAL;
685 }
686 
687 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
688 {
689 	return -EINVAL;
690 }
691 
692 void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
693 {
694 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
695 	unsigned long mask, val;
696 
697 	if (READ_ONCE(vcpu->arch.irqs_pending_mask)) {
698 		mask = xchg_acquire(&vcpu->arch.irqs_pending_mask, 0);
699 		val = READ_ONCE(vcpu->arch.irqs_pending) & mask;
700 
701 		csr->hvip &= ~mask;
702 		csr->hvip |= val;
703 	}
704 }
705 
706 void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
707 {
708 	unsigned long hvip;
709 	struct kvm_vcpu_arch *v = &vcpu->arch;
710 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
711 
712 	/* Read current HVIP and VSIE CSRs */
713 	csr->vsie = csr_read(CSR_VSIE);
714 
715 	/* Sync-up HVIP.VSSIP bit changes does by Guest */
716 	hvip = csr_read(CSR_HVIP);
717 	if ((csr->hvip ^ hvip) & (1UL << IRQ_VS_SOFT)) {
718 		if (hvip & (1UL << IRQ_VS_SOFT)) {
719 			if (!test_and_set_bit(IRQ_VS_SOFT,
720 					      &v->irqs_pending_mask))
721 				set_bit(IRQ_VS_SOFT, &v->irqs_pending);
722 		} else {
723 			if (!test_and_set_bit(IRQ_VS_SOFT,
724 					      &v->irqs_pending_mask))
725 				clear_bit(IRQ_VS_SOFT, &v->irqs_pending);
726 		}
727 	}
728 
729 	/* Sync-up timer CSRs */
730 	kvm_riscv_vcpu_timer_sync(vcpu);
731 }
732 
733 int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
734 {
735 	if (irq != IRQ_VS_SOFT &&
736 	    irq != IRQ_VS_TIMER &&
737 	    irq != IRQ_VS_EXT)
738 		return -EINVAL;
739 
740 	set_bit(irq, &vcpu->arch.irqs_pending);
741 	smp_mb__before_atomic();
742 	set_bit(irq, &vcpu->arch.irqs_pending_mask);
743 
744 	kvm_vcpu_kick(vcpu);
745 
746 	return 0;
747 }
748 
749 int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
750 {
751 	if (irq != IRQ_VS_SOFT &&
752 	    irq != IRQ_VS_TIMER &&
753 	    irq != IRQ_VS_EXT)
754 		return -EINVAL;
755 
756 	clear_bit(irq, &vcpu->arch.irqs_pending);
757 	smp_mb__before_atomic();
758 	set_bit(irq, &vcpu->arch.irqs_pending_mask);
759 
760 	return 0;
761 }
762 
763 bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask)
764 {
765 	unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
766 			    << VSIP_TO_HVIP_SHIFT) & mask;
767 
768 	return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false;
769 }
770 
771 void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
772 {
773 	vcpu->arch.power_off = true;
774 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
775 	kvm_vcpu_kick(vcpu);
776 }
777 
778 void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu)
779 {
780 	vcpu->arch.power_off = false;
781 	kvm_vcpu_wake_up(vcpu);
782 }
783 
784 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
785 				    struct kvm_mp_state *mp_state)
786 {
787 	if (vcpu->arch.power_off)
788 		mp_state->mp_state = KVM_MP_STATE_STOPPED;
789 	else
790 		mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
791 
792 	return 0;
793 }
794 
795 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
796 				    struct kvm_mp_state *mp_state)
797 {
798 	int ret = 0;
799 
800 	switch (mp_state->mp_state) {
801 	case KVM_MP_STATE_RUNNABLE:
802 		vcpu->arch.power_off = false;
803 		break;
804 	case KVM_MP_STATE_STOPPED:
805 		kvm_riscv_vcpu_power_off(vcpu);
806 		break;
807 	default:
808 		ret = -EINVAL;
809 	}
810 
811 	return ret;
812 }
813 
814 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
815 					struct kvm_guest_debug *dbg)
816 {
817 	/* TODO; To be implemented later. */
818 	return -EINVAL;
819 }
820 
821 static void kvm_riscv_vcpu_update_config(const unsigned long *isa)
822 {
823 	u64 henvcfg = 0;
824 
825 	if (riscv_isa_extension_available(isa, SVPBMT))
826 		henvcfg |= ENVCFG_PBMTE;
827 
828 	if (riscv_isa_extension_available(isa, SSTC))
829 		henvcfg |= ENVCFG_STCE;
830 
831 	if (riscv_isa_extension_available(isa, ZICBOM))
832 		henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE);
833 
834 	csr_write(CSR_HENVCFG, henvcfg);
835 #ifdef CONFIG_32BIT
836 	csr_write(CSR_HENVCFGH, henvcfg >> 32);
837 #endif
838 }
839 
840 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
841 {
842 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
843 
844 	csr_write(CSR_VSSTATUS, csr->vsstatus);
845 	csr_write(CSR_VSIE, csr->vsie);
846 	csr_write(CSR_VSTVEC, csr->vstvec);
847 	csr_write(CSR_VSSCRATCH, csr->vsscratch);
848 	csr_write(CSR_VSEPC, csr->vsepc);
849 	csr_write(CSR_VSCAUSE, csr->vscause);
850 	csr_write(CSR_VSTVAL, csr->vstval);
851 	csr_write(CSR_HVIP, csr->hvip);
852 	csr_write(CSR_VSATP, csr->vsatp);
853 
854 	kvm_riscv_vcpu_update_config(vcpu->arch.isa);
855 
856 	kvm_riscv_gstage_update_hgatp(vcpu);
857 
858 	kvm_riscv_vcpu_timer_restore(vcpu);
859 
860 	kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context);
861 	kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
862 					vcpu->arch.isa);
863 
864 	vcpu->cpu = cpu;
865 }
866 
867 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
868 {
869 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
870 
871 	vcpu->cpu = -1;
872 
873 	kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
874 				     vcpu->arch.isa);
875 	kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
876 
877 	kvm_riscv_vcpu_timer_save(vcpu);
878 
879 	csr->vsstatus = csr_read(CSR_VSSTATUS);
880 	csr->vsie = csr_read(CSR_VSIE);
881 	csr->vstvec = csr_read(CSR_VSTVEC);
882 	csr->vsscratch = csr_read(CSR_VSSCRATCH);
883 	csr->vsepc = csr_read(CSR_VSEPC);
884 	csr->vscause = csr_read(CSR_VSCAUSE);
885 	csr->vstval = csr_read(CSR_VSTVAL);
886 	csr->hvip = csr_read(CSR_HVIP);
887 	csr->vsatp = csr_read(CSR_VSATP);
888 }
889 
890 static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu)
891 {
892 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
893 
894 	if (kvm_request_pending(vcpu)) {
895 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) {
896 			kvm_vcpu_srcu_read_unlock(vcpu);
897 			rcuwait_wait_event(wait,
898 				(!vcpu->arch.power_off) && (!vcpu->arch.pause),
899 				TASK_INTERRUPTIBLE);
900 			kvm_vcpu_srcu_read_lock(vcpu);
901 
902 			if (vcpu->arch.power_off || vcpu->arch.pause) {
903 				/*
904 				 * Awaken to handle a signal, request to
905 				 * sleep again later.
906 				 */
907 				kvm_make_request(KVM_REQ_SLEEP, vcpu);
908 			}
909 		}
910 
911 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
912 			kvm_riscv_reset_vcpu(vcpu);
913 
914 		if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu))
915 			kvm_riscv_gstage_update_hgatp(vcpu);
916 
917 		if (kvm_check_request(KVM_REQ_FENCE_I, vcpu))
918 			kvm_riscv_fence_i_process(vcpu);
919 
920 		/*
921 		 * The generic KVM_REQ_TLB_FLUSH is same as
922 		 * KVM_REQ_HFENCE_GVMA_VMID_ALL
923 		 */
924 		if (kvm_check_request(KVM_REQ_HFENCE_GVMA_VMID_ALL, vcpu))
925 			kvm_riscv_hfence_gvma_vmid_all_process(vcpu);
926 
927 		if (kvm_check_request(KVM_REQ_HFENCE_VVMA_ALL, vcpu))
928 			kvm_riscv_hfence_vvma_all_process(vcpu);
929 
930 		if (kvm_check_request(KVM_REQ_HFENCE, vcpu))
931 			kvm_riscv_hfence_process(vcpu);
932 	}
933 }
934 
935 static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
936 {
937 	struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
938 
939 	csr_write(CSR_HVIP, csr->hvip);
940 }
941 
942 /*
943  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
944  * the vCPU is running.
945  *
946  * This must be noinstr as instrumentation may make use of RCU, and this is not
947  * safe during the EQS.
948  */
949 static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu)
950 {
951 	guest_state_enter_irqoff();
952 	__kvm_riscv_switch_to(&vcpu->arch);
953 	vcpu->arch.last_exit_cpu = vcpu->cpu;
954 	guest_state_exit_irqoff();
955 }
956 
957 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
958 {
959 	int ret;
960 	struct kvm_cpu_trap trap;
961 	struct kvm_run *run = vcpu->run;
962 
963 	/* Mark this VCPU ran at least once */
964 	vcpu->arch.ran_atleast_once = true;
965 
966 	kvm_vcpu_srcu_read_lock(vcpu);
967 
968 	switch (run->exit_reason) {
969 	case KVM_EXIT_MMIO:
970 		/* Process MMIO value returned from user-space */
971 		ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run);
972 		break;
973 	case KVM_EXIT_RISCV_SBI:
974 		/* Process SBI value returned from user-space */
975 		ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run);
976 		break;
977 	case KVM_EXIT_RISCV_CSR:
978 		/* Process CSR value returned from user-space */
979 		ret = kvm_riscv_vcpu_csr_return(vcpu, vcpu->run);
980 		break;
981 	default:
982 		ret = 0;
983 		break;
984 	}
985 	if (ret) {
986 		kvm_vcpu_srcu_read_unlock(vcpu);
987 		return ret;
988 	}
989 
990 	if (run->immediate_exit) {
991 		kvm_vcpu_srcu_read_unlock(vcpu);
992 		return -EINTR;
993 	}
994 
995 	vcpu_load(vcpu);
996 
997 	kvm_sigset_activate(vcpu);
998 
999 	ret = 1;
1000 	run->exit_reason = KVM_EXIT_UNKNOWN;
1001 	while (ret > 0) {
1002 		/* Check conditions before entering the guest */
1003 		ret = xfer_to_guest_mode_handle_work(vcpu);
1004 		if (ret)
1005 			continue;
1006 		ret = 1;
1007 
1008 		kvm_riscv_gstage_vmid_update(vcpu);
1009 
1010 		kvm_riscv_check_vcpu_requests(vcpu);
1011 
1012 		local_irq_disable();
1013 
1014 		/*
1015 		 * Ensure we set mode to IN_GUEST_MODE after we disable
1016 		 * interrupts and before the final VCPU requests check.
1017 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
1018 		 * Documentation/virt/kvm/vcpu-requests.rst
1019 		 */
1020 		vcpu->mode = IN_GUEST_MODE;
1021 
1022 		kvm_vcpu_srcu_read_unlock(vcpu);
1023 		smp_mb__after_srcu_read_unlock();
1024 
1025 		/*
1026 		 * We might have got VCPU interrupts updated asynchronously
1027 		 * so update it in HW.
1028 		 */
1029 		kvm_riscv_vcpu_flush_interrupts(vcpu);
1030 
1031 		/* Update HVIP CSR for current CPU */
1032 		kvm_riscv_update_hvip(vcpu);
1033 
1034 		if (ret <= 0 ||
1035 		    kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) ||
1036 		    kvm_request_pending(vcpu) ||
1037 		    xfer_to_guest_mode_work_pending()) {
1038 			vcpu->mode = OUTSIDE_GUEST_MODE;
1039 			local_irq_enable();
1040 			kvm_vcpu_srcu_read_lock(vcpu);
1041 			continue;
1042 		}
1043 
1044 		/*
1045 		 * Cleanup stale TLB enteries
1046 		 *
1047 		 * Note: This should be done after G-stage VMID has been
1048 		 * updated using kvm_riscv_gstage_vmid_ver_changed()
1049 		 */
1050 		kvm_riscv_local_tlb_sanitize(vcpu);
1051 
1052 		guest_timing_enter_irqoff();
1053 
1054 		kvm_riscv_vcpu_enter_exit(vcpu);
1055 
1056 		vcpu->mode = OUTSIDE_GUEST_MODE;
1057 		vcpu->stat.exits++;
1058 
1059 		/*
1060 		 * Save SCAUSE, STVAL, HTVAL, and HTINST because we might
1061 		 * get an interrupt between __kvm_riscv_switch_to() and
1062 		 * local_irq_enable() which can potentially change CSRs.
1063 		 */
1064 		trap.sepc = vcpu->arch.guest_context.sepc;
1065 		trap.scause = csr_read(CSR_SCAUSE);
1066 		trap.stval = csr_read(CSR_STVAL);
1067 		trap.htval = csr_read(CSR_HTVAL);
1068 		trap.htinst = csr_read(CSR_HTINST);
1069 
1070 		/* Syncup interrupts state with HW */
1071 		kvm_riscv_vcpu_sync_interrupts(vcpu);
1072 
1073 		preempt_disable();
1074 
1075 		/*
1076 		 * We must ensure that any pending interrupts are taken before
1077 		 * we exit guest timing so that timer ticks are accounted as
1078 		 * guest time. Transiently unmask interrupts so that any
1079 		 * pending interrupts are taken.
1080 		 *
1081 		 * There's no barrier which ensures that pending interrupts are
1082 		 * recognised, so we just hope that the CPU takes any pending
1083 		 * interrupts between the enable and disable.
1084 		 */
1085 		local_irq_enable();
1086 		local_irq_disable();
1087 
1088 		guest_timing_exit_irqoff();
1089 
1090 		local_irq_enable();
1091 
1092 		preempt_enable();
1093 
1094 		kvm_vcpu_srcu_read_lock(vcpu);
1095 
1096 		ret = kvm_riscv_vcpu_exit(vcpu, run, &trap);
1097 	}
1098 
1099 	kvm_sigset_deactivate(vcpu);
1100 
1101 	vcpu_put(vcpu);
1102 
1103 	kvm_vcpu_srcu_read_unlock(vcpu);
1104 
1105 	return ret;
1106 }
1107