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 unsigned long vcpu_get_vsesr(struct kvm_vcpu *vcpu)
116 {
117 	return vcpu->arch.vsesr_el2;
118 }
119 
120 static inline void vcpu_set_vsesr(struct kvm_vcpu *vcpu, u64 vsesr)
121 {
122 	vcpu->arch.vsesr_el2 = vsesr;
123 }
124 
125 static __always_inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
126 {
127 	return (unsigned long *)&vcpu_gp_regs(vcpu)->pc;
128 }
129 
130 static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
131 {
132 	return (unsigned long *)&vcpu_gp_regs(vcpu)->pstate;
133 }
134 
135 static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
136 {
137 	return !!(*vcpu_cpsr(vcpu) & PSR_MODE32_BIT);
138 }
139 
140 static __always_inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
141 {
142 	if (vcpu_mode_is_32bit(vcpu))
143 		return kvm_condition_valid32(vcpu);
144 
145 	return true;
146 }
147 
148 static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
149 {
150 	*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
151 }
152 
153 /*
154  * vcpu_get_reg and vcpu_set_reg should always be passed a register number
155  * coming from a read of ESR_EL2. Otherwise, it may give the wrong result on
156  * AArch32 with banked registers.
157  */
158 static __always_inline unsigned long vcpu_get_reg(const struct kvm_vcpu *vcpu,
159 					 u8 reg_num)
160 {
161 	return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)->regs[reg_num];
162 }
163 
164 static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
165 				unsigned long val)
166 {
167 	if (reg_num != 31)
168 		vcpu_gp_regs(vcpu)->regs[reg_num] = val;
169 }
170 
171 static inline unsigned long vcpu_read_spsr(const struct kvm_vcpu *vcpu)
172 {
173 	if (vcpu_mode_is_32bit(vcpu))
174 		return vcpu_read_spsr32(vcpu);
175 
176 	if (vcpu->arch.sysregs_loaded_on_cpu)
177 		return read_sysreg_el1(SYS_SPSR);
178 	else
179 		return __vcpu_sys_reg(vcpu, SPSR_EL1);
180 }
181 
182 static inline void vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long v)
183 {
184 	if (vcpu_mode_is_32bit(vcpu)) {
185 		vcpu_write_spsr32(vcpu, v);
186 		return;
187 	}
188 
189 	if (vcpu->arch.sysregs_loaded_on_cpu)
190 		write_sysreg_el1(v, SYS_SPSR);
191 	else
192 		__vcpu_sys_reg(vcpu, SPSR_EL1) = v;
193 }
194 
195 /*
196  * The layout of SPSR for an AArch32 state is different when observed from an
197  * AArch64 SPSR_ELx or an AArch32 SPSR_*. This function generates the AArch32
198  * view given an AArch64 view.
199  *
200  * In ARM DDI 0487E.a see:
201  *
202  * - The AArch64 view (SPSR_EL2) in section C5.2.18, page C5-426
203  * - The AArch32 view (SPSR_abt) in section G8.2.126, page G8-6256
204  * - The AArch32 view (SPSR_und) in section G8.2.132, page G8-6280
205  *
206  * Which show the following differences:
207  *
208  * | Bit | AA64 | AA32 | Notes                       |
209  * +-----+------+------+-----------------------------|
210  * | 24  | DIT  | J    | J is RES0 in ARMv8          |
211  * | 21  | SS   | DIT  | SS doesn't exist in AArch32 |
212  *
213  * ... and all other bits are (currently) common.
214  */
215 static inline unsigned long host_spsr_to_spsr32(unsigned long spsr)
216 {
217 	const unsigned long overlap = BIT(24) | BIT(21);
218 	unsigned long dit = !!(spsr & PSR_AA32_DIT_BIT);
219 
220 	spsr &= ~overlap;
221 
222 	spsr |= dit << 21;
223 
224 	return spsr;
225 }
226 
227 static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
228 {
229 	u32 mode;
230 
231 	if (vcpu_mode_is_32bit(vcpu)) {
232 		mode = *vcpu_cpsr(vcpu) & PSR_AA32_MODE_MASK;
233 		return mode > PSR_AA32_MODE_USR;
234 	}
235 
236 	mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
237 
238 	return mode != PSR_MODE_EL0t;
239 }
240 
241 static __always_inline u32 kvm_vcpu_get_esr(const struct kvm_vcpu *vcpu)
242 {
243 	return vcpu->arch.fault.esr_el2;
244 }
245 
246 static __always_inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
247 {
248 	u32 esr = kvm_vcpu_get_esr(vcpu);
249 
250 	if (esr & ESR_ELx_CV)
251 		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
252 
253 	return -1;
254 }
255 
256 static __always_inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
257 {
258 	return vcpu->arch.fault.far_el2;
259 }
260 
261 static __always_inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
262 {
263 	return ((phys_addr_t)vcpu->arch.fault.hpfar_el2 & HPFAR_MASK) << 8;
264 }
265 
266 static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
267 {
268 	return vcpu->arch.fault.disr_el1;
269 }
270 
271 static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
272 {
273 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_xVC_IMM_MASK;
274 }
275 
276 static __always_inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu)
277 {
278 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_ISV);
279 }
280 
281 static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu)
282 {
283 	return kvm_vcpu_get_esr(vcpu) & (ESR_ELx_CM | ESR_ELx_WNR | ESR_ELx_FSC);
284 }
285 
286 static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu)
287 {
288 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_SSE);
289 }
290 
291 static inline bool kvm_vcpu_dabt_issf(const struct kvm_vcpu *vcpu)
292 {
293 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_SF);
294 }
295 
296 static __always_inline int kvm_vcpu_dabt_get_rd(const struct kvm_vcpu *vcpu)
297 {
298 	return (kvm_vcpu_get_esr(vcpu) & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT;
299 }
300 
301 static __always_inline bool kvm_vcpu_dabt_iss1tw(const struct kvm_vcpu *vcpu)
302 {
303 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_S1PTW);
304 }
305 
306 static __always_inline bool kvm_vcpu_dabt_iswrite(const struct kvm_vcpu *vcpu)
307 {
308 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_WNR) ||
309 		kvm_vcpu_dabt_iss1tw(vcpu); /* AF/DBM update */
310 }
311 
312 static inline bool kvm_vcpu_dabt_is_cm(const struct kvm_vcpu *vcpu)
313 {
314 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_CM);
315 }
316 
317 static __always_inline unsigned int kvm_vcpu_dabt_get_as(const struct kvm_vcpu *vcpu)
318 {
319 	return 1 << ((kvm_vcpu_get_esr(vcpu) & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT);
320 }
321 
322 /* This one is not specific to Data Abort */
323 static __always_inline bool kvm_vcpu_trap_il_is32bit(const struct kvm_vcpu *vcpu)
324 {
325 	return !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_IL);
326 }
327 
328 static __always_inline u8 kvm_vcpu_trap_get_class(const struct kvm_vcpu *vcpu)
329 {
330 	return ESR_ELx_EC(kvm_vcpu_get_esr(vcpu));
331 }
332 
333 static inline bool kvm_vcpu_trap_is_iabt(const struct kvm_vcpu *vcpu)
334 {
335 	return kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_IABT_LOW;
336 }
337 
338 static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
339 {
340 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC;
341 }
342 
343 static __always_inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vcpu)
344 {
345 	return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC_TYPE;
346 }
347 
348 static __always_inline bool kvm_vcpu_abt_issea(const struct kvm_vcpu *vcpu)
349 {
350 	switch (kvm_vcpu_trap_get_fault(vcpu)) {
351 	case FSC_SEA:
352 	case FSC_SEA_TTW0:
353 	case FSC_SEA_TTW1:
354 	case FSC_SEA_TTW2:
355 	case FSC_SEA_TTW3:
356 	case FSC_SECC:
357 	case FSC_SECC_TTW0:
358 	case FSC_SECC_TTW1:
359 	case FSC_SECC_TTW2:
360 	case FSC_SECC_TTW3:
361 		return true;
362 	default:
363 		return false;
364 	}
365 }
366 
367 static __always_inline int kvm_vcpu_sys_get_rt(struct kvm_vcpu *vcpu)
368 {
369 	u32 esr = kvm_vcpu_get_esr(vcpu);
370 	return ESR_ELx_SYS64_ISS_RT(esr);
371 }
372 
373 static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
374 {
375 	if (kvm_vcpu_trap_is_iabt(vcpu))
376 		return false;
377 
378 	return kvm_vcpu_dabt_iswrite(vcpu);
379 }
380 
381 static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
382 {
383 	return vcpu_read_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
384 }
385 
386 static inline bool kvm_arm_get_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu)
387 {
388 	return vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG;
389 }
390 
391 static inline void kvm_arm_set_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu,
392 						      bool flag)
393 {
394 	if (flag)
395 		vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
396 	else
397 		vcpu->arch.workaround_flags &= ~VCPU_WORKAROUND_2_FLAG;
398 }
399 
400 static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
401 {
402 	if (vcpu_mode_is_32bit(vcpu)) {
403 		*vcpu_cpsr(vcpu) |= PSR_AA32_E_BIT;
404 	} else {
405 		u64 sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
406 		sctlr |= (1 << 25);
407 		vcpu_write_sys_reg(vcpu, sctlr, SCTLR_EL1);
408 	}
409 }
410 
411 static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
412 {
413 	if (vcpu_mode_is_32bit(vcpu))
414 		return !!(*vcpu_cpsr(vcpu) & PSR_AA32_E_BIT);
415 
416 	return !!(vcpu_read_sys_reg(vcpu, SCTLR_EL1) & (1 << 25));
417 }
418 
419 static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
420 						    unsigned long data,
421 						    unsigned int len)
422 {
423 	if (kvm_vcpu_is_be(vcpu)) {
424 		switch (len) {
425 		case 1:
426 			return data & 0xff;
427 		case 2:
428 			return be16_to_cpu(data & 0xffff);
429 		case 4:
430 			return be32_to_cpu(data & 0xffffffff);
431 		default:
432 			return be64_to_cpu(data);
433 		}
434 	} else {
435 		switch (len) {
436 		case 1:
437 			return data & 0xff;
438 		case 2:
439 			return le16_to_cpu(data & 0xffff);
440 		case 4:
441 			return le32_to_cpu(data & 0xffffffff);
442 		default:
443 			return le64_to_cpu(data);
444 		}
445 	}
446 
447 	return data;		/* Leave LE untouched */
448 }
449 
450 static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
451 						    unsigned long data,
452 						    unsigned int len)
453 {
454 	if (kvm_vcpu_is_be(vcpu)) {
455 		switch (len) {
456 		case 1:
457 			return data & 0xff;
458 		case 2:
459 			return cpu_to_be16(data & 0xffff);
460 		case 4:
461 			return cpu_to_be32(data & 0xffffffff);
462 		default:
463 			return cpu_to_be64(data);
464 		}
465 	} else {
466 		switch (len) {
467 		case 1:
468 			return data & 0xff;
469 		case 2:
470 			return cpu_to_le16(data & 0xffff);
471 		case 4:
472 			return cpu_to_le32(data & 0xffffffff);
473 		default:
474 			return cpu_to_le64(data);
475 		}
476 	}
477 
478 	return data;		/* Leave LE untouched */
479 }
480 
481 static __always_inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
482 {
483 	if (vcpu_mode_is_32bit(vcpu)) {
484 		kvm_skip_instr32(vcpu, is_wide_instr);
485 	} else {
486 		*vcpu_pc(vcpu) += 4;
487 		*vcpu_cpsr(vcpu) &= ~PSR_BTYPE_MASK;
488 	}
489 
490 	/* advance the singlestep state machine */
491 	*vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
492 }
493 
494 /*
495  * Skip an instruction which has been emulated at hyp while most guest sysregs
496  * are live.
497  */
498 static __always_inline void __kvm_skip_instr(struct kvm_vcpu *vcpu)
499 {
500 	*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
501 	vcpu_gp_regs(vcpu)->pstate = read_sysreg_el2(SYS_SPSR);
502 
503 	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
504 
505 	write_sysreg_el2(vcpu_gp_regs(vcpu)->pstate, SYS_SPSR);
506 	write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
507 }
508 
509 #endif /* __ARM64_KVM_EMULATE_H__ */
510