xref: /linux/arch/arm64/include/asm/kvm_emulate.h (revision 07f0148aafe8c95a3a76cd59e9e75b4d78d1d31d)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012,2013 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  *
6  * Derived from arch/arm/include/kvm_emulate.h
7  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
8  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
9  */
10 
11 #ifndef __ARM64_KVM_EMULATE_H__
12 #define __ARM64_KVM_EMULATE_H__
13 
14 #include <linux/kvm_host.h>
15 
16 #include <asm/debug-monitors.h>
17 #include <asm/esr.h>
18 #include <asm/kvm_arm.h>
19 #include <asm/kvm_hyp.h>
20 #include <asm/ptrace.h>
21 #include <asm/cputype.h>
22 #include <asm/virt.h>
23 
24 #define CURRENT_EL_SP_EL0_VECTOR	0x0
25 #define CURRENT_EL_SP_ELx_VECTOR	0x200
26 #define LOWER_EL_AArch64_VECTOR		0x400
27 #define LOWER_EL_AArch32_VECTOR		0x600
28 
29 enum exception_type {
30 	except_type_sync	= 0,
31 	except_type_irq		= 0x80,
32 	except_type_fiq		= 0x100,
33 	except_type_serror	= 0x180,
34 };
35 
36 bool kvm_condition_valid32(const struct kvm_vcpu *vcpu);
37 void kvm_skip_instr32(struct kvm_vcpu *vcpu);
38 
39 void kvm_inject_undefined(struct kvm_vcpu *vcpu);
40 void kvm_inject_vabt(struct kvm_vcpu *vcpu);
41 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
42 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
43 void kvm_inject_size_fault(struct kvm_vcpu *vcpu);
44 
45 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu);
46 
47 #if defined(__KVM_VHE_HYPERVISOR__) || defined(__KVM_NVHE_HYPERVISOR__)
48 static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
49 {
50 	return !(vcpu->arch.hcr_el2 & HCR_RW);
51 }
52 #else
53 static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
54 {
55 	struct kvm *kvm = vcpu->kvm;
56 
57 	WARN_ON_ONCE(!test_bit(KVM_ARCH_FLAG_REG_WIDTH_CONFIGURED,
58 			       &kvm->arch.flags));
59 
60 	return test_bit(KVM_ARCH_FLAG_EL1_32BIT, &kvm->arch.flags);
61 }
62 #endif
63 
64 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
65 {
66 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
67 	if (is_kernel_in_hyp_mode())
68 		vcpu->arch.hcr_el2 |= HCR_E2H;
69 	if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN)) {
70 		/* route synchronous external abort exceptions to EL2 */
71 		vcpu->arch.hcr_el2 |= HCR_TEA;
72 		/* trap error record accesses */
73 		vcpu->arch.hcr_el2 |= HCR_TERR;
74 	}
75 
76 	if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) {
77 		vcpu->arch.hcr_el2 |= HCR_FWB;
78 	} else {
79 		/*
80 		 * For non-FWB CPUs, we trap VM ops (HCR_EL2.TVM) until M+C
81 		 * get set in SCTLR_EL1 such that we can detect when the guest
82 		 * MMU gets turned on and do the necessary cache maintenance
83 		 * then.
84 		 */
85 		vcpu->arch.hcr_el2 |= HCR_TVM;
86 	}
87 
88 	if (vcpu_el1_is_32bit(vcpu))
89 		vcpu->arch.hcr_el2 &= ~HCR_RW;
90 
91 	if (cpus_have_const_cap(ARM64_MISMATCHED_CACHE_TYPE) ||
92 	    vcpu_el1_is_32bit(vcpu))
93 		vcpu->arch.hcr_el2 |= HCR_TID2;
94 
95 	if (kvm_has_mte(vcpu->kvm))
96 		vcpu->arch.hcr_el2 |= HCR_ATA;
97 }
98 
99 static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
100 {
101 	return (unsigned long *)&vcpu->arch.hcr_el2;
102 }
103 
104 static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
105 {
106 	vcpu->arch.hcr_el2 &= ~HCR_TWE;
107 	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
108 	    vcpu->kvm->arch.vgic.nassgireq)
109 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
110 	else
111 		vcpu->arch.hcr_el2 |= HCR_TWI;
112 }
113 
114 static inline void vcpu_set_wfx_traps(struct kvm_vcpu *vcpu)
115 {
116 	vcpu->arch.hcr_el2 |= HCR_TWE;
117 	vcpu->arch.hcr_el2 |= HCR_TWI;
118 }
119 
120 static inline void vcpu_ptrauth_enable(struct kvm_vcpu *vcpu)
121 {
122 	vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
123 }
124 
125 static inline void vcpu_ptrauth_disable(struct kvm_vcpu *vcpu)
126 {
127 	vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
128 }
129 
130 static inline unsigned long vcpu_get_vsesr(struct kvm_vcpu *vcpu)
131 {
132 	return vcpu->arch.vsesr_el2;
133 }
134 
135 static inline void vcpu_set_vsesr(struct kvm_vcpu *vcpu, u64 vsesr)
136 {
137 	vcpu->arch.vsesr_el2 = vsesr;
138 }
139 
140 static __always_inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
141 {
142 	return (unsigned long *)&vcpu_gp_regs(vcpu)->pc;
143 }
144 
145 static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
146 {
147 	return (unsigned long *)&vcpu_gp_regs(vcpu)->pstate;
148 }
149 
150 static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
151 {
152 	return !!(*vcpu_cpsr(vcpu) & PSR_MODE32_BIT);
153 }
154 
155 static __always_inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
156 {
157 	if (vcpu_mode_is_32bit(vcpu))
158 		return kvm_condition_valid32(vcpu);
159 
160 	return true;
161 }
162 
163 static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
164 {
165 	*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
166 }
167 
168 /*
169  * vcpu_get_reg and vcpu_set_reg should always be passed a register number
170  * coming from a read of ESR_EL2. Otherwise, it may give the wrong result on
171  * AArch32 with banked registers.
172  */
173 static __always_inline unsigned long vcpu_get_reg(const struct kvm_vcpu *vcpu,
174 					 u8 reg_num)
175 {
176 	return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)->regs[reg_num];
177 }
178 
179 static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
180 				unsigned long val)
181 {
182 	if (reg_num != 31)
183 		vcpu_gp_regs(vcpu)->regs[reg_num] = val;
184 }
185 
186 /*
187  * The layout of SPSR for an AArch32 state is different when observed from an
188  * AArch64 SPSR_ELx or an AArch32 SPSR_*. This function generates the AArch32
189  * view given an AArch64 view.
190  *
191  * In ARM DDI 0487E.a see:
192  *
193  * - The AArch64 view (SPSR_EL2) in section C5.2.18, page C5-426
194  * - The AArch32 view (SPSR_abt) in section G8.2.126, page G8-6256
195  * - The AArch32 view (SPSR_und) in section G8.2.132, page G8-6280
196  *
197  * Which show the following differences:
198  *
199  * | Bit | AA64 | AA32 | Notes                       |
200  * +-----+------+------+-----------------------------|
201  * | 24  | DIT  | J    | J is RES0 in ARMv8          |
202  * | 21  | SS   | DIT  | SS doesn't exist in AArch32 |
203  *
204  * ... and all other bits are (currently) common.
205  */
206 static inline unsigned long host_spsr_to_spsr32(unsigned long spsr)
207 {
208 	const unsigned long overlap = BIT(24) | BIT(21);
209 	unsigned long dit = !!(spsr & PSR_AA32_DIT_BIT);
210 
211 	spsr &= ~overlap;
212 
213 	spsr |= dit << 21;
214 
215 	return spsr;
216 }
217 
218 static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
219 {
220 	u32 mode;
221 
222 	if (vcpu_mode_is_32bit(vcpu)) {
223 		mode = *vcpu_cpsr(vcpu) & PSR_AA32_MODE_MASK;
224 		return mode > PSR_AA32_MODE_USR;
225 	}
226 
227 	mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
228 
229 	return mode != PSR_MODE_EL0t;
230 }
231 
232 static __always_inline u64 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
233 {
234 	return vcpu->arch.fault.esr_el2;
235 }
236 
237 static __always_inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
238 {
239 	u64 esr = kvm_vcpu_get_esr(vcpu);
240 
241 	if (esr & ESR_ELx_CV)
242 		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
243 
244 	return -1;
245 }
246 
247 static __always_inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
248 {
249 	return vcpu->arch.fault.far_el2;
250 }
251 
252 static __always_inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
253 {
254 	return ((phys_addr_t)vcpu->arch.fault.hpfar_el2 & HPFAR_MASK) << 8;
255 }
256 
257 static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
258 {
259 	return vcpu->arch.fault.disr_el1;
260 }
261 
262 static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
263 {
264 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_xVC_IMM_MASK;
265 }
266 
267 static __always_inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu)
268 {
269 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_ISV);
270 }
271 
272 static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu)
273 {
274 	return kvm_vcpu_get_esr(vcpu) & (ESR_ELx_CM | ESR_ELx_WNR | ESR_ELx_FSC);
275 }
276 
277 static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu)
278 {
279 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_SSE);
280 }
281 
282 static inline bool kvm_vcpu_dabt_issf(const struct kvm_vcpu *vcpu)
283 {
284 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_SF);
285 }
286 
287 static __always_inline int kvm_vcpu_dabt_get_rd(const struct kvm_vcpu *vcpu)
288 {
289 	return (kvm_vcpu_get_esr(vcpu) & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT;
290 }
291 
292 static __always_inline bool kvm_vcpu_abt_iss1tw(const struct kvm_vcpu *vcpu)
293 {
294 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_S1PTW);
295 }
296 
297 /* Always check for S1PTW *before* using this. */
298 static __always_inline bool kvm_vcpu_dabt_iswrite(const struct kvm_vcpu *vcpu)
299 {
300 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_WNR;
301 }
302 
303 static inline bool kvm_vcpu_dabt_is_cm(const struct kvm_vcpu *vcpu)
304 {
305 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_CM);
306 }
307 
308 static __always_inline unsigned int kvm_vcpu_dabt_get_as(const struct kvm_vcpu *vcpu)
309 {
310 	return 1 << ((kvm_vcpu_get_esr(vcpu) & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT);
311 }
312 
313 /* This one is not specific to Data Abort */
314 static __always_inline bool kvm_vcpu_trap_il_is32bit(const struct kvm_vcpu *vcpu)
315 {
316 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_IL);
317 }
318 
319 static __always_inline u8 kvm_vcpu_trap_get_class(const struct kvm_vcpu *vcpu)
320 {
321 	return ESR_ELx_EC(kvm_vcpu_get_esr(vcpu));
322 }
323 
324 static inline bool kvm_vcpu_trap_is_iabt(const struct kvm_vcpu *vcpu)
325 {
326 	return kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_IABT_LOW;
327 }
328 
329 static inline bool kvm_vcpu_trap_is_exec_fault(const struct kvm_vcpu *vcpu)
330 {
331 	return kvm_vcpu_trap_is_iabt(vcpu) && !kvm_vcpu_abt_iss1tw(vcpu);
332 }
333 
334 static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
335 {
336 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC;
337 }
338 
339 static __always_inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vcpu)
340 {
341 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC_TYPE;
342 }
343 
344 static __always_inline u8 kvm_vcpu_trap_get_fault_level(const struct kvm_vcpu *vcpu)
345 {
346 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC_LEVEL;
347 }
348 
349 static __always_inline bool kvm_vcpu_abt_issea(const struct kvm_vcpu *vcpu)
350 {
351 	switch (kvm_vcpu_trap_get_fault(vcpu)) {
352 	case ESR_ELx_FSC_EXTABT:
353 	case ESR_ELx_FSC_SEA_TTW0:
354 	case ESR_ELx_FSC_SEA_TTW1:
355 	case ESR_ELx_FSC_SEA_TTW2:
356 	case ESR_ELx_FSC_SEA_TTW3:
357 	case ESR_ELx_FSC_SECC:
358 	case ESR_ELx_FSC_SECC_TTW0:
359 	case ESR_ELx_FSC_SECC_TTW1:
360 	case ESR_ELx_FSC_SECC_TTW2:
361 	case ESR_ELx_FSC_SECC_TTW3:
362 		return true;
363 	default:
364 		return false;
365 	}
366 }
367 
368 static __always_inline int kvm_vcpu_sys_get_rt(struct kvm_vcpu *vcpu)
369 {
370 	u64 esr = kvm_vcpu_get_esr(vcpu);
371 	return ESR_ELx_SYS64_ISS_RT(esr);
372 }
373 
374 static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
375 {
376 	if (kvm_vcpu_abt_iss1tw(vcpu)) {
377 		/*
378 		 * Only a permission fault on a S1PTW should be
379 		 * considered as a write. Otherwise, page tables baked
380 		 * in a read-only memslot will result in an exception
381 		 * being delivered in the guest.
382 		 *
383 		 * The drawback is that we end-up faulting twice if the
384 		 * guest is using any of HW AF/DB: a translation fault
385 		 * to map the page containing the PT (read only at
386 		 * first), then a permission fault to allow the flags
387 		 * to be set.
388 		 */
389 		switch (kvm_vcpu_trap_get_fault_type(vcpu)) {
390 		case ESR_ELx_FSC_PERM:
391 			return true;
392 		default:
393 			return false;
394 		}
395 	}
396 
397 	if (kvm_vcpu_trap_is_iabt(vcpu))
398 		return false;
399 
400 	return kvm_vcpu_dabt_iswrite(vcpu);
401 }
402 
403 static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
404 {
405 	return vcpu_read_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
406 }
407 
408 static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
409 {
410 	if (vcpu_mode_is_32bit(vcpu)) {
411 		*vcpu_cpsr(vcpu) |= PSR_AA32_E_BIT;
412 	} else {
413 		u64 sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
414 		sctlr |= SCTLR_ELx_EE;
415 		vcpu_write_sys_reg(vcpu, sctlr, SCTLR_EL1);
416 	}
417 }
418 
419 static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
420 {
421 	if (vcpu_mode_is_32bit(vcpu))
422 		return !!(*vcpu_cpsr(vcpu) & PSR_AA32_E_BIT);
423 
424 	if (vcpu_mode_priv(vcpu))
425 		return !!(vcpu_read_sys_reg(vcpu, SCTLR_EL1) & SCTLR_ELx_EE);
426 	else
427 		return !!(vcpu_read_sys_reg(vcpu, SCTLR_EL1) & SCTLR_EL1_E0E);
428 }
429 
430 static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
431 						    unsigned long data,
432 						    unsigned int len)
433 {
434 	if (kvm_vcpu_is_be(vcpu)) {
435 		switch (len) {
436 		case 1:
437 			return data & 0xff;
438 		case 2:
439 			return be16_to_cpu(data & 0xffff);
440 		case 4:
441 			return be32_to_cpu(data & 0xffffffff);
442 		default:
443 			return be64_to_cpu(data);
444 		}
445 	} else {
446 		switch (len) {
447 		case 1:
448 			return data & 0xff;
449 		case 2:
450 			return le16_to_cpu(data & 0xffff);
451 		case 4:
452 			return le32_to_cpu(data & 0xffffffff);
453 		default:
454 			return le64_to_cpu(data);
455 		}
456 	}
457 
458 	return data;		/* Leave LE untouched */
459 }
460 
461 static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
462 						    unsigned long data,
463 						    unsigned int len)
464 {
465 	if (kvm_vcpu_is_be(vcpu)) {
466 		switch (len) {
467 		case 1:
468 			return data & 0xff;
469 		case 2:
470 			return cpu_to_be16(data & 0xffff);
471 		case 4:
472 			return cpu_to_be32(data & 0xffffffff);
473 		default:
474 			return cpu_to_be64(data);
475 		}
476 	} else {
477 		switch (len) {
478 		case 1:
479 			return data & 0xff;
480 		case 2:
481 			return cpu_to_le16(data & 0xffff);
482 		case 4:
483 			return cpu_to_le32(data & 0xffffffff);
484 		default:
485 			return cpu_to_le64(data);
486 		}
487 	}
488 
489 	return data;		/* Leave LE untouched */
490 }
491 
492 static __always_inline void kvm_incr_pc(struct kvm_vcpu *vcpu)
493 {
494 	WARN_ON(vcpu_get_flag(vcpu, PENDING_EXCEPTION));
495 	vcpu_set_flag(vcpu, INCREMENT_PC);
496 }
497 
498 #define kvm_pend_exception(v, e)					\
499 	do {								\
500 		WARN_ON(vcpu_get_flag((v), INCREMENT_PC));		\
501 		vcpu_set_flag((v), PENDING_EXCEPTION);			\
502 		vcpu_set_flag((v), e);					\
503 	} while (0)
504 
505 
506 static inline bool vcpu_has_feature(struct kvm_vcpu *vcpu, int feature)
507 {
508 	return test_bit(feature, vcpu->arch.features);
509 }
510 
511 #endif /* __ARM64_KVM_EMULATE_H__ */
512