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 unsigned long *vcpu_reg32(const struct kvm_vcpu *vcpu, u8 reg_num);
25 unsigned long vcpu_read_spsr32(const struct kvm_vcpu *vcpu);
26 void vcpu_write_spsr32(struct kvm_vcpu *vcpu, unsigned long v);
27 
28 bool kvm_condition_valid32(const struct kvm_vcpu *vcpu);
29 void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr);
30 
31 void kvm_inject_undefined(struct kvm_vcpu *vcpu);
32 void kvm_inject_vabt(struct kvm_vcpu *vcpu);
33 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
34 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
35 void kvm_inject_undef32(struct kvm_vcpu *vcpu);
36 void kvm_inject_dabt32(struct kvm_vcpu *vcpu, unsigned long addr);
37 void kvm_inject_pabt32(struct kvm_vcpu *vcpu, unsigned long addr);
38 
39 static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
40 {
41 	return !(vcpu->arch.hcr_el2 & HCR_RW);
42 }
43 
44 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
45 {
46 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
47 	if (is_kernel_in_hyp_mode())
48 		vcpu->arch.hcr_el2 |= HCR_E2H;
49 	if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN)) {
50 		/* route synchronous external abort exceptions to EL2 */
51 		vcpu->arch.hcr_el2 |= HCR_TEA;
52 		/* trap error record accesses */
53 		vcpu->arch.hcr_el2 |= HCR_TERR;
54 	}
55 
56 	if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) {
57 		vcpu->arch.hcr_el2 |= HCR_FWB;
58 	} else {
59 		/*
60 		 * For non-FWB CPUs, we trap VM ops (HCR_EL2.TVM) until M+C
61 		 * get set in SCTLR_EL1 such that we can detect when the guest
62 		 * MMU gets turned on and do the necessary cache maintenance
63 		 * then.
64 		 */
65 		vcpu->arch.hcr_el2 |= HCR_TVM;
66 	}
67 
68 	if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features))
69 		vcpu->arch.hcr_el2 &= ~HCR_RW;
70 
71 	/*
72 	 * TID3: trap feature register accesses that we virtualise.
73 	 * For now this is conditional, since no AArch32 feature regs
74 	 * are currently virtualised.
75 	 */
76 	if (!vcpu_el1_is_32bit(vcpu))
77 		vcpu->arch.hcr_el2 |= HCR_TID3;
78 
79 	if (cpus_have_const_cap(ARM64_MISMATCHED_CACHE_TYPE) ||
80 	    vcpu_el1_is_32bit(vcpu))
81 		vcpu->arch.hcr_el2 |= HCR_TID2;
82 }
83 
84 static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
85 {
86 	return (unsigned long *)&vcpu->arch.hcr_el2;
87 }
88 
89 static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
90 {
91 	vcpu->arch.hcr_el2 &= ~HCR_TWE;
92 	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
93 	    vcpu->kvm->arch.vgic.nassgireq)
94 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
95 	else
96 		vcpu->arch.hcr_el2 |= HCR_TWI;
97 }
98 
99 static inline void vcpu_set_wfx_traps(struct kvm_vcpu *vcpu)
100 {
101 	vcpu->arch.hcr_el2 |= HCR_TWE;
102 	vcpu->arch.hcr_el2 |= HCR_TWI;
103 }
104 
105 static inline void vcpu_ptrauth_enable(struct kvm_vcpu *vcpu)
106 {
107 	vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
108 }
109 
110 static inline void vcpu_ptrauth_disable(struct kvm_vcpu *vcpu)
111 {
112 	vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
113 }
114 
115 static inline void vcpu_ptrauth_setup_lazy(struct kvm_vcpu *vcpu)
116 {
117 	if (vcpu_has_ptrauth(vcpu))
118 		vcpu_ptrauth_disable(vcpu);
119 }
120 
121 static inline unsigned long vcpu_get_vsesr(struct kvm_vcpu *vcpu)
122 {
123 	return vcpu->arch.vsesr_el2;
124 }
125 
126 static inline void vcpu_set_vsesr(struct kvm_vcpu *vcpu, u64 vsesr)
127 {
128 	vcpu->arch.vsesr_el2 = vsesr;
129 }
130 
131 static __always_inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
132 {
133 	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pc;
134 }
135 
136 static inline unsigned long *__vcpu_elr_el1(const struct kvm_vcpu *vcpu)
137 {
138 	return (unsigned long *)&vcpu_gp_regs(vcpu)->elr_el1;
139 }
140 
141 static inline unsigned long vcpu_read_elr_el1(const struct kvm_vcpu *vcpu)
142 {
143 	if (vcpu->arch.sysregs_loaded_on_cpu)
144 		return read_sysreg_el1(SYS_ELR);
145 	else
146 		return *__vcpu_elr_el1(vcpu);
147 }
148 
149 static inline void vcpu_write_elr_el1(const struct kvm_vcpu *vcpu, unsigned long v)
150 {
151 	if (vcpu->arch.sysregs_loaded_on_cpu)
152 		write_sysreg_el1(v, SYS_ELR);
153 	else
154 		*__vcpu_elr_el1(vcpu) = v;
155 }
156 
157 static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
158 {
159 	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pstate;
160 }
161 
162 static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
163 {
164 	return !!(*vcpu_cpsr(vcpu) & PSR_MODE32_BIT);
165 }
166 
167 static __always_inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
168 {
169 	if (vcpu_mode_is_32bit(vcpu))
170 		return kvm_condition_valid32(vcpu);
171 
172 	return true;
173 }
174 
175 static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
176 {
177 	*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
178 }
179 
180 /*
181  * vcpu_get_reg and vcpu_set_reg should always be passed a register number
182  * coming from a read of ESR_EL2. Otherwise, it may give the wrong result on
183  * AArch32 with banked registers.
184  */
185 static __always_inline unsigned long vcpu_get_reg(const struct kvm_vcpu *vcpu,
186 					 u8 reg_num)
187 {
188 	return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)->regs.regs[reg_num];
189 }
190 
191 static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
192 				unsigned long val)
193 {
194 	if (reg_num != 31)
195 		vcpu_gp_regs(vcpu)->regs.regs[reg_num] = val;
196 }
197 
198 static inline unsigned long vcpu_read_spsr(const struct kvm_vcpu *vcpu)
199 {
200 	if (vcpu_mode_is_32bit(vcpu))
201 		return vcpu_read_spsr32(vcpu);
202 
203 	if (vcpu->arch.sysregs_loaded_on_cpu)
204 		return read_sysreg_el1(SYS_SPSR);
205 	else
206 		return vcpu_gp_regs(vcpu)->spsr[KVM_SPSR_EL1];
207 }
208 
209 static inline void vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long v)
210 {
211 	if (vcpu_mode_is_32bit(vcpu)) {
212 		vcpu_write_spsr32(vcpu, v);
213 		return;
214 	}
215 
216 	if (vcpu->arch.sysregs_loaded_on_cpu)
217 		write_sysreg_el1(v, SYS_SPSR);
218 	else
219 		vcpu_gp_regs(vcpu)->spsr[KVM_SPSR_EL1] = v;
220 }
221 
222 /*
223  * The layout of SPSR for an AArch32 state is different when observed from an
224  * AArch64 SPSR_ELx or an AArch32 SPSR_*. This function generates the AArch32
225  * view given an AArch64 view.
226  *
227  * In ARM DDI 0487E.a see:
228  *
229  * - The AArch64 view (SPSR_EL2) in section C5.2.18, page C5-426
230  * - The AArch32 view (SPSR_abt) in section G8.2.126, page G8-6256
231  * - The AArch32 view (SPSR_und) in section G8.2.132, page G8-6280
232  *
233  * Which show the following differences:
234  *
235  * | Bit | AA64 | AA32 | Notes                       |
236  * +-----+------+------+-----------------------------|
237  * | 24  | DIT  | J    | J is RES0 in ARMv8          |
238  * | 21  | SS   | DIT  | SS doesn't exist in AArch32 |
239  *
240  * ... and all other bits are (currently) common.
241  */
242 static inline unsigned long host_spsr_to_spsr32(unsigned long spsr)
243 {
244 	const unsigned long overlap = BIT(24) | BIT(21);
245 	unsigned long dit = !!(spsr & PSR_AA32_DIT_BIT);
246 
247 	spsr &= ~overlap;
248 
249 	spsr |= dit << 21;
250 
251 	return spsr;
252 }
253 
254 static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
255 {
256 	u32 mode;
257 
258 	if (vcpu_mode_is_32bit(vcpu)) {
259 		mode = *vcpu_cpsr(vcpu) & PSR_AA32_MODE_MASK;
260 		return mode > PSR_AA32_MODE_USR;
261 	}
262 
263 	mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
264 
265 	return mode != PSR_MODE_EL0t;
266 }
267 
268 static __always_inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu)
269 {
270 	return vcpu->arch.fault.esr_el2;
271 }
272 
273 static __always_inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
274 {
275 	u32 esr = kvm_vcpu_get_hsr(vcpu);
276 
277 	if (esr & ESR_ELx_CV)
278 		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
279 
280 	return -1;
281 }
282 
283 static __always_inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
284 {
285 	return vcpu->arch.fault.far_el2;
286 }
287 
288 static __always_inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
289 {
290 	return ((phys_addr_t)vcpu->arch.fault.hpfar_el2 & HPFAR_MASK) << 8;
291 }
292 
293 static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
294 {
295 	return vcpu->arch.fault.disr_el1;
296 }
297 
298 static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
299 {
300 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_xVC_IMM_MASK;
301 }
302 
303 static __always_inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu)
304 {
305 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_ISV);
306 }
307 
308 static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu)
309 {
310 	return kvm_vcpu_get_hsr(vcpu) & (ESR_ELx_CM | ESR_ELx_WNR | ESR_ELx_FSC);
311 }
312 
313 static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu)
314 {
315 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SSE);
316 }
317 
318 static inline bool kvm_vcpu_dabt_issf(const struct kvm_vcpu *vcpu)
319 {
320 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SF);
321 }
322 
323 static __always_inline int kvm_vcpu_dabt_get_rd(const struct kvm_vcpu *vcpu)
324 {
325 	return (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT;
326 }
327 
328 static __always_inline bool kvm_vcpu_dabt_iss1tw(const struct kvm_vcpu *vcpu)
329 {
330 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_S1PTW);
331 }
332 
333 static __always_inline bool kvm_vcpu_dabt_iswrite(const struct kvm_vcpu *vcpu)
334 {
335 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WNR) ||
336 		kvm_vcpu_dabt_iss1tw(vcpu); /* AF/DBM update */
337 }
338 
339 static inline bool kvm_vcpu_dabt_is_cm(const struct kvm_vcpu *vcpu)
340 {
341 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_CM);
342 }
343 
344 static __always_inline unsigned int kvm_vcpu_dabt_get_as(const struct kvm_vcpu *vcpu)
345 {
346 	return 1 << ((kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT);
347 }
348 
349 /* This one is not specific to Data Abort */
350 static __always_inline bool kvm_vcpu_trap_il_is32bit(const struct kvm_vcpu *vcpu)
351 {
352 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_IL);
353 }
354 
355 static __always_inline u8 kvm_vcpu_trap_get_class(const struct kvm_vcpu *vcpu)
356 {
357 	return ESR_ELx_EC(kvm_vcpu_get_hsr(vcpu));
358 }
359 
360 static inline bool kvm_vcpu_trap_is_iabt(const struct kvm_vcpu *vcpu)
361 {
362 	return kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_IABT_LOW;
363 }
364 
365 static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
366 {
367 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_FSC;
368 }
369 
370 static __always_inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vcpu)
371 {
372 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_FSC_TYPE;
373 }
374 
375 static __always_inline bool kvm_vcpu_dabt_isextabt(const struct kvm_vcpu *vcpu)
376 {
377 	switch (kvm_vcpu_trap_get_fault(vcpu)) {
378 	case FSC_SEA:
379 	case FSC_SEA_TTW0:
380 	case FSC_SEA_TTW1:
381 	case FSC_SEA_TTW2:
382 	case FSC_SEA_TTW3:
383 	case FSC_SECC:
384 	case FSC_SECC_TTW0:
385 	case FSC_SECC_TTW1:
386 	case FSC_SECC_TTW2:
387 	case FSC_SECC_TTW3:
388 		return true;
389 	default:
390 		return false;
391 	}
392 }
393 
394 static __always_inline int kvm_vcpu_sys_get_rt(struct kvm_vcpu *vcpu)
395 {
396 	u32 esr = kvm_vcpu_get_hsr(vcpu);
397 	return ESR_ELx_SYS64_ISS_RT(esr);
398 }
399 
400 static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
401 {
402 	if (kvm_vcpu_trap_is_iabt(vcpu))
403 		return false;
404 
405 	return kvm_vcpu_dabt_iswrite(vcpu);
406 }
407 
408 static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
409 {
410 	return vcpu_read_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
411 }
412 
413 static inline bool kvm_arm_get_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu)
414 {
415 	return vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG;
416 }
417 
418 static inline void kvm_arm_set_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu,
419 						      bool flag)
420 {
421 	if (flag)
422 		vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
423 	else
424 		vcpu->arch.workaround_flags &= ~VCPU_WORKAROUND_2_FLAG;
425 }
426 
427 static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
428 {
429 	if (vcpu_mode_is_32bit(vcpu)) {
430 		*vcpu_cpsr(vcpu) |= PSR_AA32_E_BIT;
431 	} else {
432 		u64 sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
433 		sctlr |= (1 << 25);
434 		vcpu_write_sys_reg(vcpu, sctlr, SCTLR_EL1);
435 	}
436 }
437 
438 static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
439 {
440 	if (vcpu_mode_is_32bit(vcpu))
441 		return !!(*vcpu_cpsr(vcpu) & PSR_AA32_E_BIT);
442 
443 	return !!(vcpu_read_sys_reg(vcpu, SCTLR_EL1) & (1 << 25));
444 }
445 
446 static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
447 						    unsigned long data,
448 						    unsigned int len)
449 {
450 	if (kvm_vcpu_is_be(vcpu)) {
451 		switch (len) {
452 		case 1:
453 			return data & 0xff;
454 		case 2:
455 			return be16_to_cpu(data & 0xffff);
456 		case 4:
457 			return be32_to_cpu(data & 0xffffffff);
458 		default:
459 			return be64_to_cpu(data);
460 		}
461 	} else {
462 		switch (len) {
463 		case 1:
464 			return data & 0xff;
465 		case 2:
466 			return le16_to_cpu(data & 0xffff);
467 		case 4:
468 			return le32_to_cpu(data & 0xffffffff);
469 		default:
470 			return le64_to_cpu(data);
471 		}
472 	}
473 
474 	return data;		/* Leave LE untouched */
475 }
476 
477 static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
478 						    unsigned long data,
479 						    unsigned int len)
480 {
481 	if (kvm_vcpu_is_be(vcpu)) {
482 		switch (len) {
483 		case 1:
484 			return data & 0xff;
485 		case 2:
486 			return cpu_to_be16(data & 0xffff);
487 		case 4:
488 			return cpu_to_be32(data & 0xffffffff);
489 		default:
490 			return cpu_to_be64(data);
491 		}
492 	} else {
493 		switch (len) {
494 		case 1:
495 			return data & 0xff;
496 		case 2:
497 			return cpu_to_le16(data & 0xffff);
498 		case 4:
499 			return cpu_to_le32(data & 0xffffffff);
500 		default:
501 			return cpu_to_le64(data);
502 		}
503 	}
504 
505 	return data;		/* Leave LE untouched */
506 }
507 
508 static __always_inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
509 {
510 	if (vcpu_mode_is_32bit(vcpu))
511 		kvm_skip_instr32(vcpu, is_wide_instr);
512 	else
513 		*vcpu_pc(vcpu) += 4;
514 
515 	/* advance the singlestep state machine */
516 	*vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
517 }
518 
519 /*
520  * Skip an instruction which has been emulated at hyp while most guest sysregs
521  * are live.
522  */
523 static __always_inline void __hyp_text __kvm_skip_instr(struct kvm_vcpu *vcpu)
524 {
525 	*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
526 	vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(SYS_SPSR);
527 
528 	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
529 
530 	write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, SYS_SPSR);
531 	write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
532 }
533 
534 #endif /* __ARM64_KVM_EMULATE_H__ */
535