xref: /linux/arch/arm64/kvm/at.c (revision 02e5f74ef08d3e6afec438d571487d0d0cec3c48)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2017 - Linaro Ltd
4  * Author: Jintack Lim <jintack.lim@linaro.org>
5  */
6 
7 #include <linux/kvm_host.h>
8 
9 #include <asm/esr.h>
10 #include <asm/kvm_hyp.h>
11 #include <asm/kvm_mmu.h>
12 
fail_s1_walk(struct s1_walk_result * wr,u8 fst,bool s1ptw)13 static void fail_s1_walk(struct s1_walk_result *wr, u8 fst, bool s1ptw)
14 {
15 	wr->fst		= fst;
16 	wr->ptw		= s1ptw;
17 	wr->s2		= s1ptw;
18 	wr->failed	= true;
19 }
20 
21 #define S1_MMU_DISABLED		(-127)
22 
get_ia_size(struct s1_walk_info * wi)23 static int get_ia_size(struct s1_walk_info *wi)
24 {
25 	return 64 - wi->txsz;
26 }
27 
28 /* Return true if the IPA is out of the OA range */
check_output_size(u64 ipa,struct s1_walk_info * wi)29 static bool check_output_size(u64 ipa, struct s1_walk_info *wi)
30 {
31 	if (wi->pa52bit)
32 		return wi->max_oa_bits < 52 && (ipa & GENMASK_ULL(51, wi->max_oa_bits));
33 	return wi->max_oa_bits < 48 && (ipa & GENMASK_ULL(47, wi->max_oa_bits));
34 }
35 
has_52bit_pa(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,u64 tcr)36 static bool has_52bit_pa(struct kvm_vcpu *vcpu, struct s1_walk_info *wi, u64 tcr)
37 {
38 	switch (BIT(wi->pgshift)) {
39 	case SZ_64K:
40 	default:		/* IMPDEF: treat any other value as 64k */
41 		if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR0_EL1, PARANGE, 52))
42 			return false;
43 		return ((wi->regime == TR_EL2 ?
44 			 FIELD_GET(TCR_EL2_PS_MASK, tcr) :
45 			 FIELD_GET(TCR_IPS_MASK, tcr)) == 0b0110);
46 	case SZ_16K:
47 		if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR0_EL1, TGRAN16, 52_BIT))
48 			return false;
49 		break;
50 	case SZ_4K:
51 		if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR0_EL1, TGRAN4, 52_BIT))
52 			return false;
53 		break;
54 	}
55 
56 	return (tcr & (wi->regime == TR_EL2 ? TCR_EL2_DS : TCR_DS));
57 }
58 
desc_to_oa(struct s1_walk_info * wi,u64 desc)59 static u64 desc_to_oa(struct s1_walk_info *wi, u64 desc)
60 {
61 	u64 addr;
62 
63 	if (!wi->pa52bit)
64 		return desc & GENMASK_ULL(47, wi->pgshift);
65 
66 	switch (BIT(wi->pgshift)) {
67 	case SZ_4K:
68 	case SZ_16K:
69 		addr = desc & GENMASK_ULL(49, wi->pgshift);
70 		addr |= FIELD_GET(KVM_PTE_ADDR_51_50_LPA2, desc) << 50;
71 		break;
72 	case SZ_64K:
73 	default:	    /* IMPDEF: treat any other value as 64k */
74 		addr = desc & GENMASK_ULL(47, wi->pgshift);
75 		addr |= FIELD_GET(KVM_PTE_ADDR_51_48, desc) << 48;
76 		break;
77 	}
78 
79 	return addr;
80 }
81 
82 /* Return the translation regime that applies to an AT instruction */
compute_translation_regime(struct kvm_vcpu * vcpu,u32 op)83 static enum trans_regime compute_translation_regime(struct kvm_vcpu *vcpu, u32 op)
84 {
85 	/*
86 	 * We only get here from guest EL2, so the translation
87 	 * regime AT applies to is solely defined by {E2H,TGE}.
88 	 */
89 	switch (op) {
90 	case OP_AT_S1E2R:
91 	case OP_AT_S1E2W:
92 	case OP_AT_S1E2A:
93 		return vcpu_el2_e2h_is_set(vcpu) ? TR_EL20 : TR_EL2;
94 	default:
95 		return (vcpu_el2_e2h_is_set(vcpu) &&
96 			vcpu_el2_tge_is_set(vcpu)) ? TR_EL20 : TR_EL10;
97 	}
98 }
99 
effective_tcr2(struct kvm_vcpu * vcpu,enum trans_regime regime)100 static u64 effective_tcr2(struct kvm_vcpu *vcpu, enum trans_regime regime)
101 {
102 	if (regime == TR_EL10) {
103 		if (vcpu_has_nv(vcpu) &&
104 		    !(__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En))
105 			return 0;
106 
107 		return vcpu_read_sys_reg(vcpu, TCR2_EL1);
108 	}
109 
110 	return vcpu_read_sys_reg(vcpu, TCR2_EL2);
111 }
112 
s1pie_enabled(struct kvm_vcpu * vcpu,enum trans_regime regime)113 static bool s1pie_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime)
114 {
115 	if (!kvm_has_s1pie(vcpu->kvm))
116 		return false;
117 
118 	/* Abuse TCR2_EL1_PIE and use it for EL2 as well */
119 	return effective_tcr2(vcpu, regime) & TCR2_EL1_PIE;
120 }
121 
compute_s1poe(struct kvm_vcpu * vcpu,struct s1_walk_info * wi)122 static void compute_s1poe(struct kvm_vcpu *vcpu, struct s1_walk_info *wi)
123 {
124 	u64 val;
125 
126 	if (!kvm_has_s1poe(vcpu->kvm)) {
127 		wi->poe = wi->e0poe = false;
128 		return;
129 	}
130 
131 	val = effective_tcr2(vcpu, wi->regime);
132 
133 	/* Abuse TCR2_EL1_* for EL2 */
134 	wi->poe = val & TCR2_EL1_POE;
135 	wi->e0poe = (wi->regime != TR_EL2) && (val & TCR2_EL1_E0POE);
136 }
137 
setup_s1_walk(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr,u64 va)138 static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
139 			 struct s1_walk_result *wr, u64 va)
140 {
141 	u64 hcr, sctlr, tcr, tg, ps, ia_bits, ttbr;
142 	unsigned int stride, x;
143 	bool va55, tbi, lva;
144 
145 	va55 = va & BIT(55);
146 
147 	if (vcpu_has_nv(vcpu)) {
148 		hcr = __vcpu_sys_reg(vcpu, HCR_EL2);
149 		wi->s2 = wi->regime == TR_EL10 && (hcr & (HCR_VM | HCR_DC));
150 	} else {
151 		WARN_ON_ONCE(wi->regime != TR_EL10);
152 		wi->s2 = false;
153 		hcr = 0;
154 	}
155 
156 	switch (wi->regime) {
157 	case TR_EL10:
158 		sctlr	= vcpu_read_sys_reg(vcpu, SCTLR_EL1);
159 		tcr	= vcpu_read_sys_reg(vcpu, TCR_EL1);
160 		ttbr	= (va55 ?
161 			   vcpu_read_sys_reg(vcpu, TTBR1_EL1) :
162 			   vcpu_read_sys_reg(vcpu, TTBR0_EL1));
163 		break;
164 	case TR_EL2:
165 	case TR_EL20:
166 		sctlr	= vcpu_read_sys_reg(vcpu, SCTLR_EL2);
167 		tcr	= vcpu_read_sys_reg(vcpu, TCR_EL2);
168 		ttbr	= (va55 ?
169 			   vcpu_read_sys_reg(vcpu, TTBR1_EL2) :
170 			   vcpu_read_sys_reg(vcpu, TTBR0_EL2));
171 		break;
172 	default:
173 		BUG();
174 	}
175 
176 	/* Someone was silly enough to encode TG0/TG1 differently */
177 	if (va55 && wi->regime != TR_EL2) {
178 		wi->txsz = FIELD_GET(TCR_T1SZ_MASK, tcr);
179 		tg = FIELD_GET(TCR_TG1_MASK, tcr);
180 
181 		switch (tg << TCR_TG1_SHIFT) {
182 		case TCR_TG1_4K:
183 			wi->pgshift = 12;	 break;
184 		case TCR_TG1_16K:
185 			wi->pgshift = 14;	 break;
186 		case TCR_TG1_64K:
187 		default:	    /* IMPDEF: treat any other value as 64k */
188 			wi->pgshift = 16;	 break;
189 		}
190 	} else {
191 		wi->txsz = FIELD_GET(TCR_T0SZ_MASK, tcr);
192 		tg = FIELD_GET(TCR_TG0_MASK, tcr);
193 
194 		switch (tg << TCR_TG0_SHIFT) {
195 		case TCR_TG0_4K:
196 			wi->pgshift = 12;	 break;
197 		case TCR_TG0_16K:
198 			wi->pgshift = 14;	 break;
199 		case TCR_TG0_64K:
200 		default:	    /* IMPDEF: treat any other value as 64k */
201 			wi->pgshift = 16;	 break;
202 		}
203 	}
204 
205 	wi->pa52bit = has_52bit_pa(vcpu, wi, tcr);
206 
207 	ia_bits = get_ia_size(wi);
208 
209 	/* AArch64.S1StartLevel() */
210 	stride = wi->pgshift - 3;
211 	wi->sl = 3 - (((ia_bits - 1) - wi->pgshift) / stride);
212 
213 	if (wi->regime == TR_EL2 && va55)
214 		goto addrsz;
215 
216 	tbi = (wi->regime == TR_EL2 ?
217 	       FIELD_GET(TCR_EL2_TBI, tcr) :
218 	       (va55 ?
219 		FIELD_GET(TCR_TBI1, tcr) :
220 		FIELD_GET(TCR_TBI0, tcr)));
221 
222 	if (!tbi && (u64)sign_extend64(va, 55) != va)
223 		goto addrsz;
224 
225 	wi->sh = (wi->regime == TR_EL2 ?
226 		  FIELD_GET(TCR_EL2_SH0_MASK, tcr) :
227 		  (va55 ?
228 		   FIELD_GET(TCR_SH1_MASK, tcr) :
229 		   FIELD_GET(TCR_SH0_MASK, tcr)));
230 
231 	va = (u64)sign_extend64(va, 55);
232 
233 	/* Let's put the MMU disabled case aside immediately */
234 	switch (wi->regime) {
235 	case TR_EL10:
236 		/*
237 		 * If dealing with the EL1&0 translation regime, 3 things
238 		 * can disable the S1 translation:
239 		 *
240 		 * - HCR_EL2.DC = 1
241 		 * - HCR_EL2.{E2H,TGE} = {0,1}
242 		 * - SCTLR_EL1.M = 0
243 		 *
244 		 * The TGE part is interesting. If we have decided that this
245 		 * is EL1&0, then it means that either {E2H,TGE} == {1,0} or
246 		 * {0,x}, and we only need to test for TGE == 1.
247 		 */
248 		if (hcr & (HCR_DC | HCR_TGE)) {
249 			wr->level = S1_MMU_DISABLED;
250 			break;
251 		}
252 		fallthrough;
253 	case TR_EL2:
254 	case TR_EL20:
255 		if (!(sctlr & SCTLR_ELx_M))
256 			wr->level = S1_MMU_DISABLED;
257 		break;
258 	}
259 
260 	if (wr->level == S1_MMU_DISABLED) {
261 		if (va >= BIT(kvm_get_pa_bits(vcpu->kvm)))
262 			goto addrsz;
263 
264 		wr->pa = va;
265 		return 0;
266 	}
267 
268 	wi->be = sctlr & SCTLR_ELx_EE;
269 
270 	wi->hpd  = kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, HPDS, IMP);
271 	wi->hpd &= (wi->regime == TR_EL2 ?
272 		    FIELD_GET(TCR_EL2_HPD, tcr) :
273 		    (va55 ?
274 		     FIELD_GET(TCR_HPD1, tcr) :
275 		     FIELD_GET(TCR_HPD0, tcr)));
276 	/* R_JHSVW */
277 	wi->hpd |= s1pie_enabled(vcpu, wi->regime);
278 
279 	/* Do we have POE? */
280 	compute_s1poe(vcpu, wi);
281 
282 	/* R_BVXDG */
283 	wi->hpd |= (wi->poe || wi->e0poe);
284 
285 	/* R_PLCGL, R_YXNYW */
286 	if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR2_EL1, ST, 48_47)) {
287 		if (wi->txsz > 39)
288 			goto transfault;
289 	} else {
290 		if (wi->txsz > 48 || (BIT(wi->pgshift) == SZ_64K && wi->txsz > 47))
291 			goto transfault;
292 	}
293 
294 	/* R_GTJBY, R_SXWGM */
295 	switch (BIT(wi->pgshift)) {
296 	case SZ_4K:
297 	case SZ_16K:
298 		lva = wi->pa52bit;
299 		break;
300 	case SZ_64K:
301 		lva = kvm_has_feat(vcpu->kvm, ID_AA64MMFR2_EL1, VARange, 52);
302 		break;
303 	}
304 
305 	if ((lva && wi->txsz < 12) || (!lva && wi->txsz < 16))
306 		goto transfault;
307 
308 	/* R_YYVYV, I_THCZK */
309 	if ((!va55 && va > GENMASK(ia_bits - 1, 0)) ||
310 	    (va55 && va < GENMASK(63, ia_bits)))
311 		goto transfault;
312 
313 	/* I_ZFSYQ */
314 	if (wi->regime != TR_EL2 &&
315 	    (tcr & (va55 ? TCR_EPD1_MASK : TCR_EPD0_MASK)))
316 		goto transfault;
317 
318 	/* R_BNDVG and following statements */
319 	if (kvm_has_feat(vcpu->kvm, ID_AA64MMFR2_EL1, E0PD, IMP) &&
320 	    wi->as_el0 && (tcr & (va55 ? TCR_E0PD1 : TCR_E0PD0)))
321 		goto transfault;
322 
323 	ps = (wi->regime == TR_EL2 ?
324 	      FIELD_GET(TCR_EL2_PS_MASK, tcr) : FIELD_GET(TCR_IPS_MASK, tcr));
325 
326 	wi->max_oa_bits = min(get_kvm_ipa_limit(), ps_to_output_size(ps, wi->pa52bit));
327 
328 	/* Compute minimal alignment */
329 	x = 3 + ia_bits - ((3 - wi->sl) * stride + wi->pgshift);
330 
331 	wi->baddr = ttbr & TTBRx_EL1_BADDR;
332 	if (wi->pa52bit) {
333 		/*
334 		 * Force the alignment on 64 bytes for top-level tables
335 		 * smaller than 8 entries, since TTBR.BADDR[5:2] are used to
336 		 * store bits [51:48] of the first level of lookup.
337 		 */
338 		x = max(x, 6);
339 
340 		wi->baddr |= FIELD_GET(GENMASK_ULL(5, 2), ttbr) << 48;
341 	}
342 
343 	/* R_VPBBF */
344 	if (check_output_size(wi->baddr, wi))
345 		goto addrsz;
346 
347 	wi->baddr &= GENMASK_ULL(wi->max_oa_bits - 1, x);
348 
349 	return 0;
350 
351 addrsz:
352 	/*
353 	 * Address Size Fault level 0 to indicate it comes from TTBR.
354 	 * yes, this is an oddity.
355 	 */
356 	fail_s1_walk(wr, ESR_ELx_FSC_ADDRSZ_L(0), false);
357 	return -EFAULT;
358 
359 transfault:
360 	/* Translation Fault on start level */
361 	fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(wi->sl), false);
362 	return -EFAULT;
363 }
364 
walk_s1(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr,u64 va)365 static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
366 		   struct s1_walk_result *wr, u64 va)
367 {
368 	u64 va_top, va_bottom, baddr, desc;
369 	int level, stride, ret;
370 
371 	level = wi->sl;
372 	stride = wi->pgshift - 3;
373 	baddr = wi->baddr;
374 
375 	va_top = get_ia_size(wi) - 1;
376 
377 	while (1) {
378 		u64 index, ipa;
379 
380 		va_bottom = (3 - level) * stride + wi->pgshift;
381 		index = (va & GENMASK_ULL(va_top, va_bottom)) >> (va_bottom - 3);
382 
383 		ipa = baddr | index;
384 
385 		if (wi->s2) {
386 			struct kvm_s2_trans s2_trans = {};
387 
388 			ret = kvm_walk_nested_s2(vcpu, ipa, &s2_trans);
389 			if (ret) {
390 				fail_s1_walk(wr,
391 					     (s2_trans.esr & ~ESR_ELx_FSC_LEVEL) | level,
392 					     true);
393 				return ret;
394 			}
395 
396 			if (!kvm_s2_trans_readable(&s2_trans)) {
397 				fail_s1_walk(wr, ESR_ELx_FSC_PERM_L(level),
398 					     true);
399 
400 				return -EPERM;
401 			}
402 
403 			ipa = kvm_s2_trans_output(&s2_trans);
404 		}
405 
406 		if (wi->filter) {
407 			ret = wi->filter->fn(&(struct s1_walk_context)
408 					     {
409 						     .wi	= wi,
410 						     .table_ipa	= baddr,
411 						     .level	= level,
412 					     }, wi->filter->priv);
413 			if (ret)
414 				return ret;
415 		}
416 
417 		ret = kvm_read_guest(vcpu->kvm, ipa, &desc, sizeof(desc));
418 		if (ret) {
419 			fail_s1_walk(wr, ESR_ELx_FSC_SEA_TTW(level), false);
420 			return ret;
421 		}
422 
423 		if (wi->be)
424 			desc = be64_to_cpu((__force __be64)desc);
425 		else
426 			desc = le64_to_cpu((__force __le64)desc);
427 
428 		/* Invalid descriptor */
429 		if (!(desc & BIT(0)))
430 			goto transfault;
431 
432 		/* Block mapping, check validity down the line */
433 		if (!(desc & BIT(1)))
434 			break;
435 
436 		/* Page mapping */
437 		if (level == 3)
438 			break;
439 
440 		/* Table handling */
441 		if (!wi->hpd) {
442 			wr->APTable  |= FIELD_GET(S1_TABLE_AP, desc);
443 			wr->UXNTable |= FIELD_GET(PMD_TABLE_UXN, desc);
444 			wr->PXNTable |= FIELD_GET(PMD_TABLE_PXN, desc);
445 		}
446 
447 		baddr = desc_to_oa(wi, desc);
448 
449 		/* Check for out-of-range OA */
450 		if (check_output_size(baddr, wi))
451 			goto addrsz;
452 
453 		/* Prepare for next round */
454 		va_top = va_bottom - 1;
455 		level++;
456 	}
457 
458 	/* Block mapping, check the validity of the level */
459 	if (!(desc & BIT(1))) {
460 		bool valid_block = false;
461 
462 		switch (BIT(wi->pgshift)) {
463 		case SZ_4K:
464 			valid_block = level == 1 || level == 2 || (wi->pa52bit && level == 0);
465 			break;
466 		case SZ_16K:
467 		case SZ_64K:
468 			valid_block = level == 2 || (wi->pa52bit && level == 1);
469 			break;
470 		}
471 
472 		if (!valid_block)
473 			goto transfault;
474 	}
475 
476 	baddr = desc_to_oa(wi, desc);
477 	if (check_output_size(baddr & GENMASK(52, va_bottom), wi))
478 		goto addrsz;
479 
480 	if (!(desc & PTE_AF)) {
481 		fail_s1_walk(wr, ESR_ELx_FSC_ACCESS_L(level), false);
482 		return -EACCES;
483 	}
484 
485 	va_bottom += contiguous_bit_shift(desc, wi, level);
486 
487 	wr->failed = false;
488 	wr->level = level;
489 	wr->desc = desc;
490 	wr->pa = baddr & GENMASK(52, va_bottom);
491 	wr->pa |= va & GENMASK_ULL(va_bottom - 1, 0);
492 
493 	wr->nG = (wi->regime != TR_EL2) && (desc & PTE_NG);
494 	if (wr->nG) {
495 		u64 asid_ttbr, tcr;
496 
497 		switch (wi->regime) {
498 		case TR_EL10:
499 			tcr = vcpu_read_sys_reg(vcpu, TCR_EL1);
500 			asid_ttbr = ((tcr & TCR_A1) ?
501 				     vcpu_read_sys_reg(vcpu, TTBR1_EL1) :
502 				     vcpu_read_sys_reg(vcpu, TTBR0_EL1));
503 			break;
504 		case TR_EL20:
505 			tcr = vcpu_read_sys_reg(vcpu, TCR_EL2);
506 			asid_ttbr = ((tcr & TCR_A1) ?
507 				     vcpu_read_sys_reg(vcpu, TTBR1_EL2) :
508 				     vcpu_read_sys_reg(vcpu, TTBR0_EL2));
509 			break;
510 		default:
511 			BUG();
512 		}
513 
514 		wr->asid = FIELD_GET(TTBR_ASID_MASK, asid_ttbr);
515 		if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR0_EL1, ASIDBITS, 16) ||
516 		    !(tcr & TCR_ASID16))
517 			wr->asid &= GENMASK(7, 0);
518 	}
519 
520 	return 0;
521 
522 addrsz:
523 	fail_s1_walk(wr, ESR_ELx_FSC_ADDRSZ_L(level), false);
524 	return -EINVAL;
525 transfault:
526 	fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(level), false);
527 	return -ENOENT;
528 }
529 
530 struct mmu_config {
531 	u64	ttbr0;
532 	u64	ttbr1;
533 	u64	tcr;
534 	u64	mair;
535 	u64	tcr2;
536 	u64	pir;
537 	u64	pire0;
538 	u64	por_el0;
539 	u64	por_el1;
540 	u64	sctlr;
541 	u64	vttbr;
542 	u64	vtcr;
543 };
544 
__mmu_config_save(struct mmu_config * config)545 static void __mmu_config_save(struct mmu_config *config)
546 {
547 	config->ttbr0	= read_sysreg_el1(SYS_TTBR0);
548 	config->ttbr1	= read_sysreg_el1(SYS_TTBR1);
549 	config->tcr	= read_sysreg_el1(SYS_TCR);
550 	config->mair	= read_sysreg_el1(SYS_MAIR);
551 	if (cpus_have_final_cap(ARM64_HAS_TCR2)) {
552 		config->tcr2	= read_sysreg_el1(SYS_TCR2);
553 		if (cpus_have_final_cap(ARM64_HAS_S1PIE)) {
554 			config->pir	= read_sysreg_el1(SYS_PIR);
555 			config->pire0	= read_sysreg_el1(SYS_PIRE0);
556 		}
557 		if (system_supports_poe()) {
558 			config->por_el1	= read_sysreg_el1(SYS_POR);
559 			config->por_el0	= read_sysreg_s(SYS_POR_EL0);
560 		}
561 	}
562 	config->sctlr	= read_sysreg_el1(SYS_SCTLR);
563 	config->vttbr	= read_sysreg(vttbr_el2);
564 	config->vtcr	= read_sysreg(vtcr_el2);
565 }
566 
__mmu_config_restore(struct mmu_config * config)567 static void __mmu_config_restore(struct mmu_config *config)
568 {
569 	/*
570 	 * ARM errata 1165522 and 1530923 require TGE to be 1 before
571 	 * we update the guest state.
572 	 */
573 	asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
574 
575 	write_sysreg_el1(config->ttbr0,	SYS_TTBR0);
576 	write_sysreg_el1(config->ttbr1,	SYS_TTBR1);
577 	write_sysreg_el1(config->tcr,	SYS_TCR);
578 	write_sysreg_el1(config->mair,	SYS_MAIR);
579 	if (cpus_have_final_cap(ARM64_HAS_TCR2)) {
580 		write_sysreg_el1(config->tcr2, SYS_TCR2);
581 		if (cpus_have_final_cap(ARM64_HAS_S1PIE)) {
582 			write_sysreg_el1(config->pir, SYS_PIR);
583 			write_sysreg_el1(config->pire0, SYS_PIRE0);
584 		}
585 		if (system_supports_poe()) {
586 			write_sysreg_el1(config->por_el1, SYS_POR);
587 			write_sysreg_s(config->por_el0, SYS_POR_EL0);
588 		}
589 	}
590 	write_sysreg_el1(config->sctlr,	SYS_SCTLR);
591 	write_sysreg(config->vttbr,	vttbr_el2);
592 	write_sysreg(config->vtcr,	vtcr_el2);
593 }
594 
at_s1e1p_fast(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)595 static bool at_s1e1p_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
596 {
597 	u64 host_pan;
598 	bool fail;
599 
600 	host_pan = read_sysreg_s(SYS_PSTATE_PAN);
601 	write_sysreg_s(*vcpu_cpsr(vcpu) & PSTATE_PAN, SYS_PSTATE_PAN);
602 
603 	switch (op) {
604 	case OP_AT_S1E1RP:
605 		fail = __kvm_at(OP_AT_S1E1RP, vaddr);
606 		break;
607 	case OP_AT_S1E1WP:
608 		fail = __kvm_at(OP_AT_S1E1WP, vaddr);
609 		break;
610 	}
611 
612 	write_sysreg_s(host_pan, SYS_PSTATE_PAN);
613 
614 	return fail;
615 }
616 
617 #define MEMATTR(ic, oc)		(MEMATTR_##oc << 4 | MEMATTR_##ic)
618 #define MEMATTR_NC		0b0100
619 #define MEMATTR_Wt		0b1000
620 #define MEMATTR_Wb		0b1100
621 #define MEMATTR_WbRaWa		0b1111
622 
623 #define MEMATTR_IS_DEVICE(m)	(((m) & GENMASK(7, 4)) == 0)
624 
s2_memattr_to_attr(u8 memattr)625 static u8 s2_memattr_to_attr(u8 memattr)
626 {
627 	memattr &= 0b1111;
628 
629 	switch (memattr) {
630 	case 0b0000:
631 	case 0b0001:
632 	case 0b0010:
633 	case 0b0011:
634 		return memattr << 2;
635 	case 0b0100:
636 		return MEMATTR(Wb, Wb);
637 	case 0b0101:
638 		return MEMATTR(NC, NC);
639 	case 0b0110:
640 		return MEMATTR(Wt, NC);
641 	case 0b0111:
642 		return MEMATTR(Wb, NC);
643 	case 0b1000:
644 		/* Reserved, assume NC */
645 		return MEMATTR(NC, NC);
646 	case 0b1001:
647 		return MEMATTR(NC, Wt);
648 	case 0b1010:
649 		return MEMATTR(Wt, Wt);
650 	case 0b1011:
651 		return MEMATTR(Wb, Wt);
652 	case 0b1100:
653 		/* Reserved, assume NC */
654 		return MEMATTR(NC, NC);
655 	case 0b1101:
656 		return MEMATTR(NC, Wb);
657 	case 0b1110:
658 		return MEMATTR(Wt, Wb);
659 	case 0b1111:
660 		return MEMATTR(Wb, Wb);
661 	default:
662 		unreachable();
663 	}
664 }
665 
combine_s1_s2_attr(u8 s1,u8 s2)666 static u8 combine_s1_s2_attr(u8 s1, u8 s2)
667 {
668 	bool transient;
669 	u8 final = 0;
670 
671 	/* Upgrade transient s1 to non-transient to simplify things */
672 	switch (s1) {
673 	case 0b0001 ... 0b0011:	/* Normal, Write-Through Transient */
674 		transient = true;
675 		s1 = MEMATTR_Wt | (s1 & GENMASK(1,0));
676 		break;
677 	case 0b0101 ... 0b0111:	/* Normal, Write-Back Transient */
678 		transient = true;
679 		s1 = MEMATTR_Wb | (s1 & GENMASK(1,0));
680 		break;
681 	default:
682 		transient = false;
683 	}
684 
685 	/* S2CombineS1AttrHints() */
686 	if ((s1 & GENMASK(3, 2)) == MEMATTR_NC ||
687 	    (s2 & GENMASK(3, 2)) == MEMATTR_NC)
688 		final = MEMATTR_NC;
689 	else if ((s1 & GENMASK(3, 2)) == MEMATTR_Wt ||
690 		 (s2 & GENMASK(3, 2)) == MEMATTR_Wt)
691 		final = MEMATTR_Wt;
692 	else
693 		final = MEMATTR_Wb;
694 
695 	if (final != MEMATTR_NC) {
696 		/* Inherit RaWa hints form S1 */
697 		if (transient) {
698 			switch (s1 & GENMASK(3, 2)) {
699 			case MEMATTR_Wt:
700 				final = 0;
701 				break;
702 			case MEMATTR_Wb:
703 				final = MEMATTR_NC;
704 				break;
705 			}
706 		}
707 
708 		final |= s1 & GENMASK(1, 0);
709 	}
710 
711 	return final;
712 }
713 
714 #define ATTR_NSH	0b00
715 #define ATTR_RSV	0b01
716 #define ATTR_OSH	0b10
717 #define ATTR_ISH	0b11
718 
compute_final_sh(u8 attr,u8 sh)719 static u8 compute_final_sh(u8 attr, u8 sh)
720 {
721 	/* Any form of device, as well as NC has SH[1:0]=0b10 */
722 	if (MEMATTR_IS_DEVICE(attr) || attr == MEMATTR(NC, NC))
723 		return ATTR_OSH;
724 
725 	if (sh == ATTR_RSV)		/* Reserved, mapped to NSH */
726 		sh = ATTR_NSH;
727 
728 	return sh;
729 }
730 
compute_s1_sh(struct s1_walk_info * wi,struct s1_walk_result * wr,u8 attr)731 static u8 compute_s1_sh(struct s1_walk_info *wi, struct s1_walk_result *wr,
732 			u8 attr)
733 {
734 	u8 sh;
735 
736 	/*
737 	 * non-52bit and LPA have their basic shareability described in the
738 	 * descriptor. LPA2 gets it from the corresponding field in TCR,
739 	 * conveniently recorded in the walk info.
740 	 */
741 	if (!wi->pa52bit || BIT(wi->pgshift) == SZ_64K)
742 		sh = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S1_SH, wr->desc);
743 	else
744 		sh = wi->sh;
745 
746 	return compute_final_sh(attr, sh);
747 }
748 
combine_sh(u8 s1_sh,u8 s2_sh)749 static u8 combine_sh(u8 s1_sh, u8 s2_sh)
750 {
751 	if (s1_sh == ATTR_OSH || s2_sh == ATTR_OSH)
752 		return ATTR_OSH;
753 	if (s1_sh == ATTR_ISH || s2_sh == ATTR_ISH)
754 		return ATTR_ISH;
755 
756 	return ATTR_NSH;
757 }
758 
compute_par_s12(struct kvm_vcpu * vcpu,u64 s1_par,struct kvm_s2_trans * tr)759 static u64 compute_par_s12(struct kvm_vcpu *vcpu, u64 s1_par,
760 			   struct kvm_s2_trans *tr)
761 {
762 	u8 s1_parattr, s2_memattr, final_attr, s2_sh;
763 	u64 par;
764 
765 	/* If S2 has failed to translate, report the damage */
766 	if (tr->esr) {
767 		par = SYS_PAR_EL1_RES1;
768 		par |= SYS_PAR_EL1_F;
769 		par |= SYS_PAR_EL1_S;
770 		par |= FIELD_PREP(SYS_PAR_EL1_FST, tr->esr);
771 		return par;
772 	}
773 
774 	s1_parattr = FIELD_GET(SYS_PAR_EL1_ATTR, s1_par);
775 	s2_memattr = FIELD_GET(GENMASK(5, 2), tr->desc);
776 
777 	if (__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_FWB) {
778 		if (!kvm_has_feat(vcpu->kvm, ID_AA64PFR2_EL1, MTEPERM, IMP))
779 			s2_memattr &= ~BIT(3);
780 
781 		/* Combination of R_VRJSW and R_RHWZM */
782 		switch (s2_memattr) {
783 		case 0b0101:
784 			if (MEMATTR_IS_DEVICE(s1_parattr))
785 				final_attr = s1_parattr;
786 			else
787 				final_attr = MEMATTR(NC, NC);
788 			break;
789 		case 0b0110:
790 		case 0b1110:
791 			final_attr = MEMATTR(WbRaWa, WbRaWa);
792 			break;
793 		case 0b0111:
794 		case 0b1111:
795 			/* Preserve S1 attribute */
796 			final_attr = s1_parattr;
797 			break;
798 		case 0b0100:
799 		case 0b1100:
800 		case 0b1101:
801 			/* Reserved, do something non-silly */
802 			final_attr = s1_parattr;
803 			break;
804 		default:
805 			/*
806 			 * MemAttr[2]=0, Device from S2.
807 			 *
808 			 * FWB does not influence the way that stage 1
809 			 * memory types and attributes are combined
810 			 * with stage 2 Device type and attributes.
811 			 */
812 			final_attr = min(s2_memattr_to_attr(s2_memattr),
813 					 s1_parattr);
814 		}
815 	} else {
816 		/* Combination of R_HMNDG, R_TNHFM and R_GQFSF */
817 		u8 s2_parattr = s2_memattr_to_attr(s2_memattr);
818 
819 		if (MEMATTR_IS_DEVICE(s1_parattr) ||
820 		    MEMATTR_IS_DEVICE(s2_parattr)) {
821 			final_attr = min(s1_parattr, s2_parattr);
822 		} else {
823 			/* At this stage, this is memory vs memory */
824 			final_attr  = combine_s1_s2_attr(s1_parattr & 0xf,
825 							 s2_parattr & 0xf);
826 			final_attr |= combine_s1_s2_attr(s1_parattr >> 4,
827 							 s2_parattr >> 4) << 4;
828 		}
829 	}
830 
831 	if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_CD) &&
832 	    !MEMATTR_IS_DEVICE(final_attr))
833 		final_attr = MEMATTR(NC, NC);
834 
835 	s2_sh = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S2_SH, tr->desc);
836 
837 	par  = FIELD_PREP(SYS_PAR_EL1_ATTR, final_attr);
838 	par |= tr->output & GENMASK(47, 12);
839 	par |= FIELD_PREP(SYS_PAR_EL1_SH,
840 			  combine_sh(FIELD_GET(SYS_PAR_EL1_SH, s1_par),
841 				     compute_final_sh(final_attr, s2_sh)));
842 
843 	return par;
844 }
845 
compute_par_s1(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)846 static u64 compute_par_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
847 			  struct s1_walk_result *wr)
848 {
849 	u64 par;
850 
851 	if (wr->failed) {
852 		par = SYS_PAR_EL1_RES1;
853 		par |= SYS_PAR_EL1_F;
854 		par |= FIELD_PREP(SYS_PAR_EL1_FST, wr->fst);
855 		par |= wr->ptw ? SYS_PAR_EL1_PTW : 0;
856 		par |= wr->s2 ? SYS_PAR_EL1_S : 0;
857 	} else if (wr->level == S1_MMU_DISABLED) {
858 		/* MMU off or HCR_EL2.DC == 1 */
859 		par  = SYS_PAR_EL1_NSE;
860 		par |= wr->pa & SYS_PAR_EL1_PA;
861 
862 		if (wi->regime == TR_EL10 && vcpu_has_nv(vcpu) &&
863 		    (__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_DC)) {
864 			par |= FIELD_PREP(SYS_PAR_EL1_ATTR,
865 					  MEMATTR(WbRaWa, WbRaWa));
866 			par |= FIELD_PREP(SYS_PAR_EL1_SH, ATTR_NSH);
867 		} else {
868 			par |= FIELD_PREP(SYS_PAR_EL1_ATTR, 0); /* nGnRnE */
869 			par |= FIELD_PREP(SYS_PAR_EL1_SH, ATTR_OSH);
870 		}
871 	} else {
872 		u64 mair, sctlr;
873 		u8 sh;
874 
875 		par  = SYS_PAR_EL1_NSE;
876 
877 		mair = (wi->regime == TR_EL10 ?
878 			vcpu_read_sys_reg(vcpu, MAIR_EL1) :
879 			vcpu_read_sys_reg(vcpu, MAIR_EL2));
880 
881 		mair >>= FIELD_GET(PTE_ATTRINDX_MASK, wr->desc) * 8;
882 		mair &= 0xff;
883 
884 		sctlr = (wi->regime == TR_EL10 ?
885 			 vcpu_read_sys_reg(vcpu, SCTLR_EL1) :
886 			 vcpu_read_sys_reg(vcpu, SCTLR_EL2));
887 
888 		/* Force NC for memory if SCTLR_ELx.C is clear */
889 		if (!(sctlr & SCTLR_EL1_C) && !MEMATTR_IS_DEVICE(mair))
890 			mair = MEMATTR(NC, NC);
891 
892 		par |= FIELD_PREP(SYS_PAR_EL1_ATTR, mair);
893 		par |= wr->pa & SYS_PAR_EL1_PA;
894 
895 		sh = compute_s1_sh(wi, wr, mair);
896 		par |= FIELD_PREP(SYS_PAR_EL1_SH, sh);
897 	}
898 
899 	return par;
900 }
901 
pan3_enabled(struct kvm_vcpu * vcpu,enum trans_regime regime)902 static bool pan3_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime)
903 {
904 	u64 sctlr;
905 
906 	if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, PAN, PAN3))
907 		return false;
908 
909 	if (s1pie_enabled(vcpu, regime))
910 		return true;
911 
912 	if (regime == TR_EL10)
913 		sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
914 	else
915 		sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL2);
916 
917 	return sctlr & SCTLR_EL1_EPAN;
918 }
919 
compute_s1_direct_permissions(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)920 static void compute_s1_direct_permissions(struct kvm_vcpu *vcpu,
921 					  struct s1_walk_info *wi,
922 					  struct s1_walk_result *wr)
923 {
924 	bool wxn;
925 
926 	/* Non-hierarchical part of AArch64.S1DirectBasePermissions() */
927 	if (wi->regime != TR_EL2) {
928 		switch (FIELD_GET(PTE_USER | PTE_RDONLY, wr->desc)) {
929 		case 0b00:
930 			wr->pr = wr->pw = true;
931 			wr->ur = wr->uw = false;
932 			break;
933 		case 0b01:
934 			wr->pr = wr->pw = wr->ur = wr->uw = true;
935 			break;
936 		case 0b10:
937 			wr->pr = true;
938 			wr->pw = wr->ur = wr->uw = false;
939 			break;
940 		case 0b11:
941 			wr->pr = wr->ur = true;
942 			wr->pw = wr->uw = false;
943 			break;
944 		}
945 
946 		/* We don't use px for anything yet, but hey... */
947 		wr->px = !((wr->desc & PTE_PXN) || wr->uw);
948 		wr->ux = !(wr->desc & PTE_UXN);
949 	} else {
950 		wr->ur = wr->uw = wr->ux = false;
951 
952 		if (!(wr->desc & PTE_RDONLY)) {
953 			wr->pr = wr->pw = true;
954 		} else {
955 			wr->pr = true;
956 			wr->pw = false;
957 		}
958 
959 		/* XN maps to UXN */
960 		wr->px = !(wr->desc & PTE_UXN);
961 	}
962 
963 	switch (wi->regime) {
964 	case TR_EL2:
965 	case TR_EL20:
966 		wxn = (vcpu_read_sys_reg(vcpu, SCTLR_EL2) & SCTLR_ELx_WXN);
967 		break;
968 	case TR_EL10:
969 		wxn = (vcpu_read_sys_reg(vcpu, SCTLR_EL1) & SCTLR_ELx_WXN);
970 		break;
971 	}
972 
973 	wr->pwxn = wr->uwxn = wxn;
974 	wr->pov = wi->poe;
975 	wr->uov = wi->e0poe;
976 }
977 
compute_s1_hierarchical_permissions(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)978 static void compute_s1_hierarchical_permissions(struct kvm_vcpu *vcpu,
979 						struct s1_walk_info *wi,
980 						struct s1_walk_result *wr)
981 {
982 	/* Hierarchical part of AArch64.S1DirectBasePermissions() */
983 	if (wi->regime != TR_EL2) {
984 		switch (wr->APTable) {
985 		case 0b00:
986 			break;
987 		case 0b01:
988 			wr->ur = wr->uw = false;
989 			break;
990 		case 0b10:
991 			wr->pw = wr->uw = false;
992 			break;
993 		case 0b11:
994 			wr->pw = wr->ur = wr->uw = false;
995 			break;
996 		}
997 
998 		wr->px &= !wr->PXNTable;
999 		wr->ux &= !wr->UXNTable;
1000 	} else {
1001 		if (wr->APTable & BIT(1))
1002 			wr->pw = false;
1003 
1004 		/* XN maps to UXN */
1005 		wr->px &= !wr->UXNTable;
1006 	}
1007 }
1008 
1009 #define perm_idx(v, r, i)	((vcpu_read_sys_reg((v), (r)) >> ((i) * 4)) & 0xf)
1010 
1011 #define set_priv_perms(wr, r, w, x)	\
1012 	do {				\
1013 		(wr)->pr = (r);		\
1014 		(wr)->pw = (w);		\
1015 		(wr)->px = (x);		\
1016 	} while (0)
1017 
1018 #define set_unpriv_perms(wr, r, w, x)	\
1019 	do {				\
1020 		(wr)->ur = (r);		\
1021 		(wr)->uw = (w);		\
1022 		(wr)->ux = (x);		\
1023 	} while (0)
1024 
1025 #define set_priv_wxn(wr, v)		\
1026 	do {				\
1027 		(wr)->pwxn = (v);	\
1028 	} while (0)
1029 
1030 #define set_unpriv_wxn(wr, v)		\
1031 	do {				\
1032 		(wr)->uwxn = (v);	\
1033 	} while (0)
1034 
1035 /* Similar to AArch64.S1IndirectBasePermissions(), without GCS  */
1036 #define set_perms(w, wr, ip)						\
1037 	do {								\
1038 		/* R_LLZDZ */						\
1039 		switch ((ip)) {						\
1040 		case 0b0000:						\
1041 			set_ ## w ## _perms((wr), false, false, false);	\
1042 			break;						\
1043 		case 0b0001:						\
1044 			set_ ## w ## _perms((wr), true , false, false);	\
1045 			break;						\
1046 		case 0b0010:						\
1047 			set_ ## w ## _perms((wr), false, false, true );	\
1048 			break;						\
1049 		case 0b0011:						\
1050 			set_ ## w ## _perms((wr), true , false, true );	\
1051 			break;						\
1052 		case 0b0100:						\
1053 			set_ ## w ## _perms((wr), false, false, false);	\
1054 			break;						\
1055 		case 0b0101:						\
1056 			set_ ## w ## _perms((wr), true , true , false);	\
1057 			break;						\
1058 		case 0b0110:						\
1059 			set_ ## w ## _perms((wr), true , true , true );	\
1060 			break;						\
1061 		case 0b0111:						\
1062 			set_ ## w ## _perms((wr), true , true , true );	\
1063 			break;						\
1064 		case 0b1000:						\
1065 			set_ ## w ## _perms((wr), true , false, false);	\
1066 			break;						\
1067 		case 0b1001:						\
1068 			set_ ## w ## _perms((wr), true , false, false);	\
1069 			break;						\
1070 		case 0b1010:						\
1071 			set_ ## w ## _perms((wr), true , false, true );	\
1072 			break;						\
1073 		case 0b1011:						\
1074 			set_ ## w ## _perms((wr), false, false, false);	\
1075 			break;						\
1076 		case 0b1100:						\
1077 			set_ ## w ## _perms((wr), true , true , false);	\
1078 			break;						\
1079 		case 0b1101:						\
1080 			set_ ## w ## _perms((wr), false, false, false);	\
1081 			break;						\
1082 		case 0b1110:						\
1083 			set_ ## w ## _perms((wr), true , true , true );	\
1084 			break;						\
1085 		case 0b1111:						\
1086 			set_ ## w ## _perms((wr), false, false, false);	\
1087 			break;						\
1088 		}							\
1089 									\
1090 		/* R_HJYGR */						\
1091 		set_ ## w ## _wxn((wr), ((ip) == 0b0110));		\
1092 									\
1093 	} while (0)
1094 
compute_s1_indirect_permissions(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)1095 static void compute_s1_indirect_permissions(struct kvm_vcpu *vcpu,
1096 					    struct s1_walk_info *wi,
1097 					    struct s1_walk_result *wr)
1098 {
1099 	u8 up, pp, idx;
1100 
1101 	idx = pte_pi_index(wr->desc);
1102 
1103 	switch (wi->regime) {
1104 	case TR_EL10:
1105 		pp = perm_idx(vcpu, PIR_EL1, idx);
1106 		up = perm_idx(vcpu, PIRE0_EL1, idx);
1107 		break;
1108 	case TR_EL20:
1109 		pp = perm_idx(vcpu, PIR_EL2, idx);
1110 		up = perm_idx(vcpu, PIRE0_EL2, idx);
1111 		break;
1112 	case TR_EL2:
1113 		pp = perm_idx(vcpu, PIR_EL2, idx);
1114 		up = 0;
1115 		break;
1116 	}
1117 
1118 	set_perms(priv, wr, pp);
1119 
1120 	if (wi->regime != TR_EL2)
1121 		set_perms(unpriv, wr, up);
1122 	else
1123 		set_unpriv_perms(wr, false, false, false);
1124 
1125 	wr->pov = wi->poe && !(pp & BIT(3));
1126 	wr->uov = wi->e0poe && !(up & BIT(3));
1127 
1128 	/* R_VFPJF */
1129 	if (wr->px && wr->uw) {
1130 		set_priv_perms(wr, false, false, false);
1131 		set_unpriv_perms(wr, false, false, false);
1132 	}
1133 }
1134 
compute_s1_overlay_permissions(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)1135 static void compute_s1_overlay_permissions(struct kvm_vcpu *vcpu,
1136 					   struct s1_walk_info *wi,
1137 					   struct s1_walk_result *wr)
1138 {
1139 	u8 idx, pov_perms, uov_perms;
1140 
1141 	idx = FIELD_GET(PTE_PO_IDX_MASK, wr->desc);
1142 
1143 	if (wr->pov) {
1144 		switch (wi->regime) {
1145 		case TR_EL10:
1146 			pov_perms = perm_idx(vcpu, POR_EL1, idx);
1147 			break;
1148 		case TR_EL20:
1149 			pov_perms = perm_idx(vcpu, POR_EL2, idx);
1150 			break;
1151 		case TR_EL2:
1152 			pov_perms = perm_idx(vcpu, POR_EL2, idx);
1153 			break;
1154 		}
1155 
1156 		if (pov_perms & ~POE_RWX)
1157 			pov_perms = POE_NONE;
1158 
1159 		/* R_QXXPC, S1PrivOverflow enabled */
1160 		if (wr->pwxn && (pov_perms & POE_X))
1161 			pov_perms &= ~POE_W;
1162 
1163 		wr->pr &= pov_perms & POE_R;
1164 		wr->pw &= pov_perms & POE_W;
1165 		wr->px &= pov_perms & POE_X;
1166 	}
1167 
1168 	if (wr->uov) {
1169 		switch (wi->regime) {
1170 		case TR_EL10:
1171 			uov_perms = perm_idx(vcpu, POR_EL0, idx);
1172 			break;
1173 		case TR_EL20:
1174 			uov_perms = perm_idx(vcpu, POR_EL0, idx);
1175 			break;
1176 		case TR_EL2:
1177 			uov_perms = 0;
1178 			break;
1179 		}
1180 
1181 		if (uov_perms & ~POE_RWX)
1182 			uov_perms = POE_NONE;
1183 
1184 		/* R_NPBXC, S1UnprivOverlay enabled */
1185 		if (wr->uwxn && (uov_perms & POE_X))
1186 			uov_perms &= ~POE_W;
1187 
1188 		wr->ur &= uov_perms & POE_R;
1189 		wr->uw &= uov_perms & POE_W;
1190 		wr->ux &= uov_perms & POE_X;
1191 	}
1192 }
1193 
compute_s1_permissions(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr)1194 static void compute_s1_permissions(struct kvm_vcpu *vcpu,
1195 				   struct s1_walk_info *wi,
1196 				   struct s1_walk_result *wr)
1197 {
1198 	bool pan;
1199 
1200 	if (!s1pie_enabled(vcpu, wi->regime))
1201 		compute_s1_direct_permissions(vcpu, wi, wr);
1202 	else
1203 		compute_s1_indirect_permissions(vcpu, wi, wr);
1204 
1205 	if (!wi->hpd)
1206 		compute_s1_hierarchical_permissions(vcpu, wi, wr);
1207 
1208 	compute_s1_overlay_permissions(vcpu, wi, wr);
1209 
1210 	/* R_QXXPC, S1PrivOverlay disabled */
1211 	if (!wr->pov)
1212 		wr->px &= !(wr->pwxn && wr->pw);
1213 
1214 	/* R_NPBXC, S1UnprivOverlay disabled */
1215 	if (!wr->uov)
1216 		wr->ux &= !(wr->uwxn && wr->uw);
1217 
1218 	pan = wi->pan && (wr->ur || wr->uw ||
1219 			  (pan3_enabled(vcpu, wi->regime) && wr->ux));
1220 	wr->pw &= !pan;
1221 	wr->pr &= !pan;
1222 }
1223 
handle_at_slow(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)1224 static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
1225 {
1226 	struct s1_walk_result wr = {};
1227 	struct s1_walk_info wi = {};
1228 	bool perm_fail = false;
1229 	int ret, idx;
1230 
1231 	wi.regime = compute_translation_regime(vcpu, op);
1232 	wi.as_el0 = (op == OP_AT_S1E0R || op == OP_AT_S1E0W);
1233 	wi.pan = (op == OP_AT_S1E1RP || op == OP_AT_S1E1WP) &&
1234 		 (*vcpu_cpsr(vcpu) & PSR_PAN_BIT);
1235 
1236 	ret = setup_s1_walk(vcpu, &wi, &wr, vaddr);
1237 	if (ret)
1238 		goto compute_par;
1239 
1240 	if (wr.level == S1_MMU_DISABLED)
1241 		goto compute_par;
1242 
1243 	idx = srcu_read_lock(&vcpu->kvm->srcu);
1244 
1245 	ret = walk_s1(vcpu, &wi, &wr, vaddr);
1246 
1247 	srcu_read_unlock(&vcpu->kvm->srcu, idx);
1248 
1249 	if (ret)
1250 		goto compute_par;
1251 
1252 	compute_s1_permissions(vcpu, &wi, &wr);
1253 
1254 	switch (op) {
1255 	case OP_AT_S1E1RP:
1256 	case OP_AT_S1E1R:
1257 	case OP_AT_S1E2R:
1258 		perm_fail = !wr.pr;
1259 		break;
1260 	case OP_AT_S1E1WP:
1261 	case OP_AT_S1E1W:
1262 	case OP_AT_S1E2W:
1263 		perm_fail = !wr.pw;
1264 		break;
1265 	case OP_AT_S1E0R:
1266 		perm_fail = !wr.ur;
1267 		break;
1268 	case OP_AT_S1E0W:
1269 		perm_fail = !wr.uw;
1270 		break;
1271 	case OP_AT_S1E1A:
1272 	case OP_AT_S1E2A:
1273 		break;
1274 	default:
1275 		BUG();
1276 	}
1277 
1278 	if (perm_fail)
1279 		fail_s1_walk(&wr, ESR_ELx_FSC_PERM_L(wr.level), false);
1280 
1281 compute_par:
1282 	return compute_par_s1(vcpu, &wi, &wr);
1283 }
1284 
1285 /*
1286  * Return the PAR_EL1 value as the result of a valid translation.
1287  *
1288  * If the translation is unsuccessful, the value may only contain
1289  * PAR_EL1.F, and cannot be taken at face value. It isn't an
1290  * indication of the translation having failed, only that the fast
1291  * path did not succeed, *unless* it indicates a S1 permission or
1292  * access fault.
1293  */
__kvm_at_s1e01_fast(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)1294 static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
1295 {
1296 	struct mmu_config config;
1297 	struct kvm_s2_mmu *mmu;
1298 	bool fail, mmu_cs;
1299 	u64 par;
1300 
1301 	par = SYS_PAR_EL1_F;
1302 
1303 	/*
1304 	 * We've trapped, so everything is live on the CPU. As we will
1305 	 * be switching contexts behind everybody's back, disable
1306 	 * interrupts while holding the mmu lock.
1307 	 */
1308 	guard(write_lock_irqsave)(&vcpu->kvm->mmu_lock);
1309 
1310 	/*
1311 	 * If HCR_EL2.{E2H,TGE} == {1,1}, the MMU context is already
1312 	 * the right one (as we trapped from vEL2). If not, save the
1313 	 * full MMU context.
1314 	 *
1315 	 * We are also guaranteed to be in the correct context if
1316 	 * we're not in a nested VM.
1317 	 */
1318 	mmu_cs = (vcpu_has_nv(vcpu) &&
1319 		  !(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)));
1320 	if (!mmu_cs)
1321 		goto skip_mmu_switch;
1322 
1323 	/*
1324 	 * Obtaining the S2 MMU for a L2 is horribly racy, and we may not
1325 	 * find it (recycled by another vcpu, for example). When this
1326 	 * happens, admit defeat immediately and use the SW (slow) path.
1327 	 */
1328 	mmu = lookup_s2_mmu(vcpu);
1329 	if (!mmu)
1330 		return par;
1331 
1332 	__mmu_config_save(&config);
1333 
1334 	write_sysreg_el1(vcpu_read_sys_reg(vcpu, TTBR0_EL1),	SYS_TTBR0);
1335 	write_sysreg_el1(vcpu_read_sys_reg(vcpu, TTBR1_EL1),	SYS_TTBR1);
1336 	write_sysreg_el1(vcpu_read_sys_reg(vcpu, TCR_EL1),	SYS_TCR);
1337 	write_sysreg_el1(vcpu_read_sys_reg(vcpu, MAIR_EL1),	SYS_MAIR);
1338 	if (kvm_has_tcr2(vcpu->kvm)) {
1339 		write_sysreg_el1(vcpu_read_sys_reg(vcpu, TCR2_EL1), SYS_TCR2);
1340 		if (kvm_has_s1pie(vcpu->kvm)) {
1341 			write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIR_EL1), SYS_PIR);
1342 			write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIRE0_EL1), SYS_PIRE0);
1343 		}
1344 		if (kvm_has_s1poe(vcpu->kvm)) {
1345 			write_sysreg_el1(vcpu_read_sys_reg(vcpu, POR_EL1), SYS_POR);
1346 			write_sysreg_s(vcpu_read_sys_reg(vcpu, POR_EL0), SYS_POR_EL0);
1347 		}
1348 	}
1349 	write_sysreg_el1(vcpu_read_sys_reg(vcpu, SCTLR_EL1),	SYS_SCTLR);
1350 	__load_stage2(mmu, mmu->arch);
1351 
1352 skip_mmu_switch:
1353 	/* Temporarily switch back to guest context */
1354 	write_sysreg_hcr(vcpu->arch.hcr_el2);
1355 	isb();
1356 
1357 	switch (op) {
1358 	case OP_AT_S1E1RP:
1359 	case OP_AT_S1E1WP:
1360 		fail = at_s1e1p_fast(vcpu, op, vaddr);
1361 		break;
1362 	case OP_AT_S1E1R:
1363 		fail = __kvm_at(OP_AT_S1E1R, vaddr);
1364 		break;
1365 	case OP_AT_S1E1W:
1366 		fail = __kvm_at(OP_AT_S1E1W, vaddr);
1367 		break;
1368 	case OP_AT_S1E0R:
1369 		fail = __kvm_at(OP_AT_S1E0R, vaddr);
1370 		break;
1371 	case OP_AT_S1E0W:
1372 		fail = __kvm_at(OP_AT_S1E0W, vaddr);
1373 		break;
1374 	case OP_AT_S1E1A:
1375 		fail = __kvm_at(OP_AT_S1E1A, vaddr);
1376 		break;
1377 	default:
1378 		WARN_ON_ONCE(1);
1379 		fail = true;
1380 		break;
1381 	}
1382 
1383 	if (!fail)
1384 		par = read_sysreg_par();
1385 
1386 	write_sysreg_hcr(HCR_HOST_VHE_FLAGS);
1387 
1388 	if (mmu_cs)
1389 		__mmu_config_restore(&config);
1390 
1391 	return par;
1392 }
1393 
par_check_s1_perm_fault(u64 par)1394 static bool par_check_s1_perm_fault(u64 par)
1395 {
1396 	u8 fst = FIELD_GET(SYS_PAR_EL1_FST, par);
1397 
1398 	return  ((fst & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_PERM &&
1399 		 !(par & SYS_PAR_EL1_S));
1400 }
1401 
par_check_s1_access_fault(u64 par)1402 static bool par_check_s1_access_fault(u64 par)
1403 {
1404 	u8 fst = FIELD_GET(SYS_PAR_EL1_FST, par);
1405 
1406 	return  ((fst & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_ACCESS &&
1407 		 !(par & SYS_PAR_EL1_S));
1408 }
1409 
__kvm_at_s1e01(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)1410 void __kvm_at_s1e01(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
1411 {
1412 	u64 par = __kvm_at_s1e01_fast(vcpu, op, vaddr);
1413 
1414 	/*
1415 	 * If PAR_EL1 reports that AT failed on a S1 permission or access
1416 	 * fault, we know for sure that the PTW was able to walk the S1
1417 	 * tables and there's nothing else to do.
1418 	 *
1419 	 * If AT failed for any other reason, then we must walk the guest S1
1420 	 * to emulate the instruction.
1421 	 */
1422 	if ((par & SYS_PAR_EL1_F) &&
1423 	    !par_check_s1_perm_fault(par) &&
1424 	    !par_check_s1_access_fault(par))
1425 		par = handle_at_slow(vcpu, op, vaddr);
1426 
1427 	vcpu_write_sys_reg(vcpu, par, PAR_EL1);
1428 }
1429 
__kvm_at_s1e2(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)1430 void __kvm_at_s1e2(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
1431 {
1432 	u64 par;
1433 
1434 	/*
1435 	 * We've trapped, so everything is live on the CPU. As we will be
1436 	 * switching context behind everybody's back, disable interrupts...
1437 	 */
1438 	scoped_guard(write_lock_irqsave, &vcpu->kvm->mmu_lock) {
1439 		u64 val, hcr;
1440 		bool fail;
1441 
1442 		val = hcr = read_sysreg(hcr_el2);
1443 		val &= ~HCR_TGE;
1444 		val |= HCR_VM;
1445 
1446 		if (!vcpu_el2_e2h_is_set(vcpu))
1447 			val |= HCR_NV | HCR_NV1;
1448 
1449 		write_sysreg_hcr(val);
1450 		isb();
1451 
1452 		par = SYS_PAR_EL1_F;
1453 
1454 		switch (op) {
1455 		case OP_AT_S1E2R:
1456 			fail = __kvm_at(OP_AT_S1E1R, vaddr);
1457 			break;
1458 		case OP_AT_S1E2W:
1459 			fail = __kvm_at(OP_AT_S1E1W, vaddr);
1460 			break;
1461 		case OP_AT_S1E2A:
1462 			fail = __kvm_at(OP_AT_S1E1A, vaddr);
1463 			break;
1464 		default:
1465 			WARN_ON_ONCE(1);
1466 			fail = true;
1467 		}
1468 
1469 		isb();
1470 
1471 		if (!fail)
1472 			par = read_sysreg_par();
1473 
1474 		write_sysreg_hcr(hcr);
1475 		isb();
1476 	}
1477 
1478 	/* We failed the translation, let's replay it in slow motion */
1479 	if ((par & SYS_PAR_EL1_F) && !par_check_s1_perm_fault(par))
1480 		par = handle_at_slow(vcpu, op, vaddr);
1481 
1482 	vcpu_write_sys_reg(vcpu, par, PAR_EL1);
1483 }
1484 
__kvm_at_s12(struct kvm_vcpu * vcpu,u32 op,u64 vaddr)1485 void __kvm_at_s12(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
1486 {
1487 	struct kvm_s2_trans out = {};
1488 	u64 ipa, par;
1489 	bool write;
1490 	int ret;
1491 
1492 	/* Do the stage-1 translation */
1493 	switch (op) {
1494 	case OP_AT_S12E1R:
1495 		op = OP_AT_S1E1R;
1496 		write = false;
1497 		break;
1498 	case OP_AT_S12E1W:
1499 		op = OP_AT_S1E1W;
1500 		write = true;
1501 		break;
1502 	case OP_AT_S12E0R:
1503 		op = OP_AT_S1E0R;
1504 		write = false;
1505 		break;
1506 	case OP_AT_S12E0W:
1507 		op = OP_AT_S1E0W;
1508 		write = true;
1509 		break;
1510 	default:
1511 		WARN_ON_ONCE(1);
1512 		return;
1513 	}
1514 
1515 	__kvm_at_s1e01(vcpu, op, vaddr);
1516 	par = vcpu_read_sys_reg(vcpu, PAR_EL1);
1517 	if (par & SYS_PAR_EL1_F)
1518 		return;
1519 
1520 	/*
1521 	 * If we only have a single stage of translation (EL2&0), exit
1522 	 * early. Same thing if {VM,DC}=={0,0}.
1523 	 */
1524 	if (compute_translation_regime(vcpu, op) == TR_EL20 ||
1525 	    !(vcpu_read_sys_reg(vcpu, HCR_EL2) & (HCR_VM | HCR_DC)))
1526 		return;
1527 
1528 	/* Do the stage-2 translation */
1529 	ipa = (par & GENMASK_ULL(47, 12)) | (vaddr & GENMASK_ULL(11, 0));
1530 	out.esr = 0;
1531 	ret = kvm_walk_nested_s2(vcpu, ipa, &out);
1532 	if (ret < 0)
1533 		return;
1534 
1535 	/* Check the access permission */
1536 	if (!out.esr &&
1537 	    ((!write && !out.readable) || (write && !out.writable)))
1538 		out.esr = ESR_ELx_FSC_PERM_L(out.level & 0x3);
1539 
1540 	par = compute_par_s12(vcpu, par, &out);
1541 	vcpu_write_sys_reg(vcpu, par, PAR_EL1);
1542 }
1543 
1544 /*
1545  * Translate a VA for a given EL in a given translation regime, with
1546  * or without PAN. This requires wi->{regime, as_el0, pan} to be
1547  * set. The rest of the wi and wr should be 0-initialised.
1548  */
__kvm_translate_va(struct kvm_vcpu * vcpu,struct s1_walk_info * wi,struct s1_walk_result * wr,u64 va)1549 int __kvm_translate_va(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
1550 		       struct s1_walk_result *wr, u64 va)
1551 {
1552 	int ret;
1553 
1554 	ret = setup_s1_walk(vcpu, wi, wr, va);
1555 	if (ret)
1556 		return ret;
1557 
1558 	if (wr->level == S1_MMU_DISABLED) {
1559 		wr->ur = wr->uw = wr->ux = true;
1560 		wr->pr = wr->pw = wr->px = true;
1561 	} else {
1562 		ret = walk_s1(vcpu, wi, wr, va);
1563 		if (ret)
1564 			return ret;
1565 
1566 		compute_s1_permissions(vcpu, wi, wr);
1567 	}
1568 
1569 	return 0;
1570 }
1571 
1572 struct desc_match {
1573 	u64	ipa;
1574 	int	level;
1575 };
1576 
match_s1_desc(struct s1_walk_context * ctxt,void * priv)1577 static int match_s1_desc(struct s1_walk_context *ctxt, void *priv)
1578 {
1579 	struct desc_match *dm = priv;
1580 	u64 ipa = dm->ipa;
1581 
1582 	/* Use S1 granule alignment */
1583 	ipa &= GENMASK(51, ctxt->wi->pgshift);
1584 
1585 	/* Not the IPA we're looking for? Continue. */
1586 	if (ipa != ctxt->table_ipa)
1587 		return 0;
1588 
1589 	/* Note the level and interrupt the walk */
1590 	dm->level = ctxt->level;
1591 	return -EINTR;
1592 }
1593 
__kvm_find_s1_desc_level(struct kvm_vcpu * vcpu,u64 va,u64 ipa,int * level)1594 int __kvm_find_s1_desc_level(struct kvm_vcpu *vcpu, u64 va, u64 ipa, int *level)
1595 {
1596 	struct desc_match dm = {
1597 		.ipa	= ipa,
1598 	};
1599 	struct s1_walk_info wi = {
1600 		.filter	= &(struct s1_walk_filter){
1601 			.fn	= match_s1_desc,
1602 			.priv	= &dm,
1603 		},
1604 		.as_el0	= false,
1605 		.pan	= false,
1606 	};
1607 	struct s1_walk_result wr = {};
1608 	int ret;
1609 
1610 	if (is_hyp_ctxt(vcpu))
1611 		wi.regime = vcpu_el2_e2h_is_set(vcpu) ? TR_EL20 : TR_EL2;
1612 	else
1613 		wi.regime = TR_EL10;
1614 
1615 	ret = setup_s1_walk(vcpu, &wi, &wr, va);
1616 	if (ret)
1617 		return ret;
1618 
1619 	/* We really expect the S1 MMU to be on here... */
1620 	if (WARN_ON_ONCE(wr.level == S1_MMU_DISABLED)) {
1621 		*level = 0;
1622 		return 0;
1623 	}
1624 
1625 	/* Walk the guest's PT, looking for a match along the way */
1626 	ret = walk_s1(vcpu, &wi, &wr, va);
1627 	switch (ret) {
1628 	case -EINTR:
1629 		/* We interrupted the walk on a match, return the level */
1630 		*level = dm.level;
1631 		return 0;
1632 	case 0:
1633 		/* The walk completed, we failed to find the entry */
1634 		return -ENOENT;
1635 	default:
1636 		/* Any other error... */
1637 		return ret;
1638 	}
1639 }
1640