1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2019 Arm Ltd.
3
4 #include <linux/arm-smccc.h>
5 #include <linux/kvm_host.h>
6
7 #include <asm/kvm_emulate.h>
8
9 #include <kvm/arm_hypercalls.h>
10 #include <kvm/arm_psci.h>
11
12 #define KVM_ARM_SMCCC_STD_FEATURES \
13 GENMASK(KVM_REG_ARM_STD_BMAP_BIT_COUNT - 1, 0)
14 #define KVM_ARM_SMCCC_STD_HYP_FEATURES \
15 GENMASK(KVM_REG_ARM_STD_HYP_BMAP_BIT_COUNT - 1, 0)
16 #define KVM_ARM_SMCCC_VENDOR_HYP_FEATURES \
17 GENMASK(KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_COUNT - 1, 0)
18
19 static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val)
20 {
21 struct system_time_snapshot systime_snapshot;
22 u64 cycles = ~0UL;
23 u32 feature;
24
25 /*
26 * system time and counter value must captured at the same
27 * time to keep consistency and precision.
28 */
29 ktime_get_snapshot(&systime_snapshot);
30
31 /*
32 * This is only valid if the current clocksource is the
33 * architected counter, as this is the only one the guest
34 * can see.
35 */
36 if (systime_snapshot.cs_id != CSID_ARM_ARCH_COUNTER)
37 return;
38
39 /*
40 * The guest selects one of the two reference counters
41 * (virtual or physical) with the first argument of the SMCCC
42 * call. In case the identifier is not supported, error out.
43 */
44 feature = smccc_get_arg1(vcpu);
45 switch (feature) {
46 case KVM_PTP_VIRT_COUNTER:
47 cycles = systime_snapshot.cycles - vcpu->kvm->arch.timer_data.voffset;
48 break;
49 case KVM_PTP_PHYS_COUNTER:
50 cycles = systime_snapshot.cycles - vcpu->kvm->arch.timer_data.poffset;
51 break;
52 default:
53 return;
54 }
55
56 /*
57 * This relies on the top bit of val[0] never being set for
58 * valid values of system time, because that is *really* far
59 * in the future (about 292 years from 1970, and at that stage
60 * nobody will give a damn about it).
61 */
62 val[0] = upper_32_bits(systime_snapshot.real);
63 val[1] = lower_32_bits(systime_snapshot.real);
64 val[2] = upper_32_bits(cycles);
65 val[3] = lower_32_bits(cycles);
66 }
67
68 static bool kvm_smccc_default_allowed(u32 func_id)
69 {
70 switch (func_id) {
71 /*
72 * List of function-ids that are not gated with the bitmapped
73 * feature firmware registers, and are to be allowed for
74 * servicing the call by default.
75 */
76 case ARM_SMCCC_VERSION_FUNC_ID:
77 case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:
78 return true;
79 default:
80 /* PSCI 0.2 and up is in the 0:0x1f range */
81 if (ARM_SMCCC_OWNER_NUM(func_id) == ARM_SMCCC_OWNER_STANDARD &&
82 ARM_SMCCC_FUNC_NUM(func_id) <= 0x1f)
83 return true;
84
85 /*
86 * KVM's PSCI 0.1 doesn't comply with SMCCC, and has
87 * its own function-id base and range
88 */
89 if (func_id >= KVM_PSCI_FN(0) && func_id <= KVM_PSCI_FN(3))
90 return true;
91
92 return false;
93 }
94 }
95
96 static bool kvm_smccc_test_fw_bmap(struct kvm_vcpu *vcpu, u32 func_id)
97 {
98 struct kvm_smccc_features *smccc_feat = &vcpu->kvm->arch.smccc_feat;
99
100 switch (func_id) {
101 case ARM_SMCCC_TRNG_VERSION:
102 case ARM_SMCCC_TRNG_FEATURES:
103 case ARM_SMCCC_TRNG_GET_UUID:
104 case ARM_SMCCC_TRNG_RND32:
105 case ARM_SMCCC_TRNG_RND64:
106 return test_bit(KVM_REG_ARM_STD_BIT_TRNG_V1_0,
107 &smccc_feat->std_bmap);
108 case ARM_SMCCC_HV_PV_TIME_FEATURES:
109 case ARM_SMCCC_HV_PV_TIME_ST:
110 return test_bit(KVM_REG_ARM_STD_HYP_BIT_PV_TIME,
111 &smccc_feat->std_hyp_bmap);
112 case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:
113 case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID:
114 return test_bit(KVM_REG_ARM_VENDOR_HYP_BIT_FUNC_FEAT,
115 &smccc_feat->vendor_hyp_bmap);
116 case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:
117 return test_bit(KVM_REG_ARM_VENDOR_HYP_BIT_PTP,
118 &smccc_feat->vendor_hyp_bmap);
119 default:
120 return false;
121 }
122 }
123
124 #define SMC32_ARCH_RANGE_BEGIN ARM_SMCCC_VERSION_FUNC_ID
125 #define SMC32_ARCH_RANGE_END ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
126 ARM_SMCCC_SMC_32, \
127 0, ARM_SMCCC_FUNC_MASK)
128
129 #define SMC64_ARCH_RANGE_BEGIN ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
130 ARM_SMCCC_SMC_64, \
131 0, 0)
132 #define SMC64_ARCH_RANGE_END ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
133 ARM_SMCCC_SMC_64, \
134 0, ARM_SMCCC_FUNC_MASK)
135
136 static int kvm_smccc_filter_insert_reserved(struct kvm *kvm)
137 {
138 int r;
139
140 /*
141 * Prevent userspace from handling any SMCCC calls in the architecture
142 * range, avoiding the risk of misrepresenting Spectre mitigation status
143 * to the guest.
144 */
145 r = mtree_insert_range(&kvm->arch.smccc_filter,
146 SMC32_ARCH_RANGE_BEGIN, SMC32_ARCH_RANGE_END,
147 xa_mk_value(KVM_SMCCC_FILTER_HANDLE),
148 GFP_KERNEL_ACCOUNT);
149 if (r)
150 goto out_destroy;
151
152 r = mtree_insert_range(&kvm->arch.smccc_filter,
153 SMC64_ARCH_RANGE_BEGIN, SMC64_ARCH_RANGE_END,
154 xa_mk_value(KVM_SMCCC_FILTER_HANDLE),
155 GFP_KERNEL_ACCOUNT);
156 if (r)
157 goto out_destroy;
158
159 return 0;
160 out_destroy:
161 mtree_destroy(&kvm->arch.smccc_filter);
162 return r;
163 }
164
165 static bool kvm_smccc_filter_configured(struct kvm *kvm)
166 {
167 return !mtree_empty(&kvm->arch.smccc_filter);
168 }
169
170 static int kvm_smccc_set_filter(struct kvm *kvm, struct kvm_smccc_filter __user *uaddr)
171 {
172 const void *zero_page = page_to_virt(ZERO_PAGE(0));
173 struct kvm_smccc_filter filter;
174 u32 start, end;
175 int r;
176
177 if (copy_from_user(&filter, uaddr, sizeof(filter)))
178 return -EFAULT;
179
180 if (memcmp(filter.pad, zero_page, sizeof(filter.pad)))
181 return -EINVAL;
182
183 start = filter.base;
184 end = start + filter.nr_functions - 1;
185
186 if (end < start || filter.action >= NR_SMCCC_FILTER_ACTIONS)
187 return -EINVAL;
188
189 mutex_lock(&kvm->arch.config_lock);
190
191 if (kvm_vm_has_ran_once(kvm)) {
192 r = -EBUSY;
193 goto out_unlock;
194 }
195
196 if (!kvm_smccc_filter_configured(kvm)) {
197 r = kvm_smccc_filter_insert_reserved(kvm);
198 if (WARN_ON_ONCE(r))
199 goto out_unlock;
200 }
201
202 r = mtree_insert_range(&kvm->arch.smccc_filter, start, end,
203 xa_mk_value(filter.action), GFP_KERNEL_ACCOUNT);
204 out_unlock:
205 mutex_unlock(&kvm->arch.config_lock);
206 return r;
207 }
208
209 static u8 kvm_smccc_filter_get_action(struct kvm *kvm, u32 func_id)
210 {
211 unsigned long idx = func_id;
212 void *val;
213
214 if (!kvm_smccc_filter_configured(kvm))
215 return KVM_SMCCC_FILTER_HANDLE;
216
217 /*
218 * But where's the error handling, you say?
219 *
220 * mt_find() returns NULL if no entry was found, which just so happens
221 * to match KVM_SMCCC_FILTER_HANDLE.
222 */
223 val = mt_find(&kvm->arch.smccc_filter, &idx, idx);
224 return xa_to_value(val);
225 }
226
227 static u8 kvm_smccc_get_action(struct kvm_vcpu *vcpu, u32 func_id)
228 {
229 /*
230 * Intervening actions in the SMCCC filter take precedence over the
231 * pseudo-firmware register bitmaps.
232 */
233 u8 action = kvm_smccc_filter_get_action(vcpu->kvm, func_id);
234 if (action != KVM_SMCCC_FILTER_HANDLE)
235 return action;
236
237 if (kvm_smccc_test_fw_bmap(vcpu, func_id) ||
238 kvm_smccc_default_allowed(func_id))
239 return KVM_SMCCC_FILTER_HANDLE;
240
241 return KVM_SMCCC_FILTER_DENY;
242 }
243
244 static void kvm_prepare_hypercall_exit(struct kvm_vcpu *vcpu, u32 func_id)
245 {
246 u8 ec = ESR_ELx_EC(kvm_vcpu_get_esr(vcpu));
247 struct kvm_run *run = vcpu->run;
248 u64 flags = 0;
249
250 if (ec == ESR_ELx_EC_SMC32 || ec == ESR_ELx_EC_SMC64)
251 flags |= KVM_HYPERCALL_EXIT_SMC;
252
253 if (!kvm_vcpu_trap_il_is32bit(vcpu))
254 flags |= KVM_HYPERCALL_EXIT_16BIT;
255
256 run->exit_reason = KVM_EXIT_HYPERCALL;
257 run->hypercall = (typeof(run->hypercall)) {
258 .nr = func_id,
259 .flags = flags,
260 };
261 }
262
263 int kvm_smccc_call_handler(struct kvm_vcpu *vcpu)
264 {
265 struct kvm_smccc_features *smccc_feat = &vcpu->kvm->arch.smccc_feat;
266 u32 func_id = smccc_get_function(vcpu);
267 u64 val[4] = {SMCCC_RET_NOT_SUPPORTED};
268 u32 feature;
269 u8 action;
270 gpa_t gpa;
271
272 action = kvm_smccc_get_action(vcpu, func_id);
273 switch (action) {
274 case KVM_SMCCC_FILTER_HANDLE:
275 break;
276 case KVM_SMCCC_FILTER_DENY:
277 goto out;
278 case KVM_SMCCC_FILTER_FWD_TO_USER:
279 kvm_prepare_hypercall_exit(vcpu, func_id);
280 return 0;
281 default:
282 WARN_RATELIMIT(1, "Unhandled SMCCC filter action: %d\n", action);
283 goto out;
284 }
285
286 switch (func_id) {
287 case ARM_SMCCC_VERSION_FUNC_ID:
288 val[0] = ARM_SMCCC_VERSION_1_1;
289 break;
290 case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:
291 feature = smccc_get_arg1(vcpu);
292 switch (feature) {
293 case ARM_SMCCC_ARCH_WORKAROUND_1:
294 switch (arm64_get_spectre_v2_state()) {
295 case SPECTRE_VULNERABLE:
296 break;
297 case SPECTRE_MITIGATED:
298 val[0] = SMCCC_RET_SUCCESS;
299 break;
300 case SPECTRE_UNAFFECTED:
301 val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
302 break;
303 }
304 break;
305 case ARM_SMCCC_ARCH_WORKAROUND_2:
306 switch (arm64_get_spectre_v4_state()) {
307 case SPECTRE_VULNERABLE:
308 break;
309 case SPECTRE_MITIGATED:
310 /*
311 * SSBS everywhere: Indicate no firmware
312 * support, as the SSBS support will be
313 * indicated to the guest and the default is
314 * safe.
315 *
316 * Otherwise, expose a permanent mitigation
317 * to the guest, and hide SSBS so that the
318 * guest stays protected.
319 */
320 if (cpus_have_final_cap(ARM64_SSBS))
321 break;
322 fallthrough;
323 case SPECTRE_UNAFFECTED:
324 val[0] = SMCCC_RET_NOT_REQUIRED;
325 break;
326 }
327 break;
328 case ARM_SMCCC_ARCH_WORKAROUND_3:
329 switch (arm64_get_spectre_bhb_state()) {
330 case SPECTRE_VULNERABLE:
331 break;
332 case SPECTRE_MITIGATED:
333 val[0] = SMCCC_RET_SUCCESS;
334 break;
335 case SPECTRE_UNAFFECTED:
336 val[0] = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
337 break;
338 }
339 break;
340 case ARM_SMCCC_HV_PV_TIME_FEATURES:
341 if (test_bit(KVM_REG_ARM_STD_HYP_BIT_PV_TIME,
342 &smccc_feat->std_hyp_bmap))
343 val[0] = SMCCC_RET_SUCCESS;
344 break;
345 }
346 break;
347 case ARM_SMCCC_HV_PV_TIME_FEATURES:
348 val[0] = kvm_hypercall_pv_features(vcpu);
349 break;
350 case ARM_SMCCC_HV_PV_TIME_ST:
351 gpa = kvm_init_stolen_time(vcpu);
352 if (gpa != INVALID_GPA)
353 val[0] = gpa;
354 break;
355 case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID:
356 val[0] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0;
357 val[1] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1;
358 val[2] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2;
359 val[3] = ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3;
360 break;
361 case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:
362 val[0] = smccc_feat->vendor_hyp_bmap;
363 break;
364 case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:
365 kvm_ptp_get_time(vcpu, val);
366 break;
367 case ARM_SMCCC_TRNG_VERSION:
368 case ARM_SMCCC_TRNG_FEATURES:
369 case ARM_SMCCC_TRNG_GET_UUID:
370 case ARM_SMCCC_TRNG_RND32:
371 case ARM_SMCCC_TRNG_RND64:
372 return kvm_trng_call(vcpu);
373 default:
374 return kvm_psci_call(vcpu);
375 }
376
377 out:
378 smccc_set_retval(vcpu, val[0], val[1], val[2], val[3]);
379 return 1;
380 }
381
382 static const u64 kvm_arm_fw_reg_ids[] = {
383 KVM_REG_ARM_PSCI_VERSION,
384 KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1,
385 KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2,
386 KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3,
387 KVM_REG_ARM_STD_BMAP,
388 KVM_REG_ARM_STD_HYP_BMAP,
389 KVM_REG_ARM_VENDOR_HYP_BMAP,
390 };
391
392 void kvm_arm_init_hypercalls(struct kvm *kvm)
393 {
394 struct kvm_smccc_features *smccc_feat = &kvm->arch.smccc_feat;
395
396 smccc_feat->std_bmap = KVM_ARM_SMCCC_STD_FEATURES;
397 smccc_feat->std_hyp_bmap = KVM_ARM_SMCCC_STD_HYP_FEATURES;
398 smccc_feat->vendor_hyp_bmap = KVM_ARM_SMCCC_VENDOR_HYP_FEATURES;
399
400 mt_init(&kvm->arch.smccc_filter);
401 }
402
403 void kvm_arm_teardown_hypercalls(struct kvm *kvm)
404 {
405 mtree_destroy(&kvm->arch.smccc_filter);
406 }
407
408 int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
409 {
410 return ARRAY_SIZE(kvm_arm_fw_reg_ids);
411 }
412
413 int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
414 {
415 int i;
416
417 for (i = 0; i < ARRAY_SIZE(kvm_arm_fw_reg_ids); i++) {
418 if (put_user(kvm_arm_fw_reg_ids[i], uindices++))
419 return -EFAULT;
420 }
421
422 return 0;
423 }
424
425 #define KVM_REG_FEATURE_LEVEL_MASK GENMASK(3, 0)
426
427 /*
428 * Convert the workaround level into an easy-to-compare number, where higher
429 * values mean better protection.
430 */
431 static int get_kernel_wa_level(u64 regid)
432 {
433 switch (regid) {
434 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
435 switch (arm64_get_spectre_v2_state()) {
436 case SPECTRE_VULNERABLE:
437 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL;
438 case SPECTRE_MITIGATED:
439 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL;
440 case SPECTRE_UNAFFECTED:
441 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED;
442 }
443 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL;
444 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2:
445 switch (arm64_get_spectre_v4_state()) {
446 case SPECTRE_MITIGATED:
447 /*
448 * As for the hypercall discovery, we pretend we
449 * don't have any FW mitigation if SSBS is there at
450 * all times.
451 */
452 if (cpus_have_final_cap(ARM64_SSBS))
453 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL;
454 fallthrough;
455 case SPECTRE_UNAFFECTED:
456 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED;
457 case SPECTRE_VULNERABLE:
458 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL;
459 }
460 break;
461 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
462 switch (arm64_get_spectre_bhb_state()) {
463 case SPECTRE_VULNERABLE:
464 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_AVAIL;
465 case SPECTRE_MITIGATED:
466 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_AVAIL;
467 case SPECTRE_UNAFFECTED:
468 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_REQUIRED;
469 }
470 return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_AVAIL;
471 }
472
473 return -EINVAL;
474 }
475
476 int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
477 {
478 struct kvm_smccc_features *smccc_feat = &vcpu->kvm->arch.smccc_feat;
479 void __user *uaddr = (void __user *)(long)reg->addr;
480 u64 val;
481
482 switch (reg->id) {
483 case KVM_REG_ARM_PSCI_VERSION:
484 val = kvm_psci_version(vcpu);
485 break;
486 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
487 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2:
488 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
489 val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK;
490 break;
491 case KVM_REG_ARM_STD_BMAP:
492 val = READ_ONCE(smccc_feat->std_bmap);
493 break;
494 case KVM_REG_ARM_STD_HYP_BMAP:
495 val = READ_ONCE(smccc_feat->std_hyp_bmap);
496 break;
497 case KVM_REG_ARM_VENDOR_HYP_BMAP:
498 val = READ_ONCE(smccc_feat->vendor_hyp_bmap);
499 break;
500 default:
501 return -ENOENT;
502 }
503
504 if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)))
505 return -EFAULT;
506
507 return 0;
508 }
509
510 static int kvm_arm_set_fw_reg_bmap(struct kvm_vcpu *vcpu, u64 reg_id, u64 val)
511 {
512 int ret = 0;
513 struct kvm *kvm = vcpu->kvm;
514 struct kvm_smccc_features *smccc_feat = &kvm->arch.smccc_feat;
515 unsigned long *fw_reg_bmap, fw_reg_features;
516
517 switch (reg_id) {
518 case KVM_REG_ARM_STD_BMAP:
519 fw_reg_bmap = &smccc_feat->std_bmap;
520 fw_reg_features = KVM_ARM_SMCCC_STD_FEATURES;
521 break;
522 case KVM_REG_ARM_STD_HYP_BMAP:
523 fw_reg_bmap = &smccc_feat->std_hyp_bmap;
524 fw_reg_features = KVM_ARM_SMCCC_STD_HYP_FEATURES;
525 break;
526 case KVM_REG_ARM_VENDOR_HYP_BMAP:
527 fw_reg_bmap = &smccc_feat->vendor_hyp_bmap;
528 fw_reg_features = KVM_ARM_SMCCC_VENDOR_HYP_FEATURES;
529 break;
530 default:
531 return -ENOENT;
532 }
533
534 /* Check for unsupported bit */
535 if (val & ~fw_reg_features)
536 return -EINVAL;
537
538 mutex_lock(&kvm->arch.config_lock);
539
540 if (kvm_vm_has_ran_once(kvm) && val != *fw_reg_bmap) {
541 ret = -EBUSY;
542 goto out;
543 }
544
545 WRITE_ONCE(*fw_reg_bmap, val);
546 out:
547 mutex_unlock(&kvm->arch.config_lock);
548 return ret;
549 }
550
551 int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
552 {
553 void __user *uaddr = (void __user *)(long)reg->addr;
554 u64 val;
555 int wa_level;
556
557 if (KVM_REG_SIZE(reg->id) != sizeof(val))
558 return -ENOENT;
559 if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id)))
560 return -EFAULT;
561
562 switch (reg->id) {
563 case KVM_REG_ARM_PSCI_VERSION:
564 {
565 bool wants_02;
566
567 wants_02 = vcpu_has_feature(vcpu, KVM_ARM_VCPU_PSCI_0_2);
568
569 switch (val) {
570 case KVM_ARM_PSCI_0_1:
571 if (wants_02)
572 return -EINVAL;
573 vcpu->kvm->arch.psci_version = val;
574 return 0;
575 case KVM_ARM_PSCI_0_2:
576 case KVM_ARM_PSCI_1_0:
577 case KVM_ARM_PSCI_1_1:
578 if (!wants_02)
579 return -EINVAL;
580 vcpu->kvm->arch.psci_version = val;
581 return 0;
582 }
583 break;
584 }
585
586 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
587 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
588 if (val & ~KVM_REG_FEATURE_LEVEL_MASK)
589 return -EINVAL;
590
591 if (get_kernel_wa_level(reg->id) < val)
592 return -EINVAL;
593
594 return 0;
595
596 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2:
597 if (val & ~(KVM_REG_FEATURE_LEVEL_MASK |
598 KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED))
599 return -EINVAL;
600
601 /* The enabled bit must not be set unless the level is AVAIL. */
602 if ((val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED) &&
603 (val & KVM_REG_FEATURE_LEVEL_MASK) != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL)
604 return -EINVAL;
605
606 /*
607 * Map all the possible incoming states to the only two we
608 * really want to deal with.
609 */
610 switch (val & KVM_REG_FEATURE_LEVEL_MASK) {
611 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL:
612 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN:
613 wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL;
614 break;
615 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL:
616 case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED:
617 wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED;
618 break;
619 default:
620 return -EINVAL;
621 }
622
623 /*
624 * We can deal with NOT_AVAIL on NOT_REQUIRED, but not the
625 * other way around.
626 */
627 if (get_kernel_wa_level(reg->id) < wa_level)
628 return -EINVAL;
629
630 return 0;
631 case KVM_REG_ARM_STD_BMAP:
632 case KVM_REG_ARM_STD_HYP_BMAP:
633 case KVM_REG_ARM_VENDOR_HYP_BMAP:
634 return kvm_arm_set_fw_reg_bmap(vcpu, reg->id, val);
635 default:
636 return -ENOENT;
637 }
638
639 return -EINVAL;
640 }
641
642 int kvm_vm_smccc_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
643 {
644 switch (attr->attr) {
645 case KVM_ARM_VM_SMCCC_FILTER:
646 return 0;
647 default:
648 return -ENXIO;
649 }
650 }
651
652 int kvm_vm_smccc_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
653 {
654 void __user *uaddr = (void __user *)attr->addr;
655
656 switch (attr->attr) {
657 case KVM_ARM_VM_SMCCC_FILTER:
658 return kvm_smccc_set_filter(kvm, uaddr);
659 default:
660 return -ENXIO;
661 }
662 }
663
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