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)->regs.pc;
128 }
129 
130 static inline unsigned long *__vcpu_elr_el1(const struct kvm_vcpu *vcpu)
131 {
132 	return (unsigned long *)&vcpu_gp_regs(vcpu)->elr_el1;
133 }
134 
135 static inline unsigned long vcpu_read_elr_el1(const struct kvm_vcpu *vcpu)
136 {
137 	if (vcpu->arch.sysregs_loaded_on_cpu)
138 		return read_sysreg_el1(SYS_ELR);
139 	else
140 		return *__vcpu_elr_el1(vcpu);
141 }
142 
143 static inline void vcpu_write_elr_el1(const struct kvm_vcpu *vcpu, unsigned long v)
144 {
145 	if (vcpu->arch.sysregs_loaded_on_cpu)
146 		write_sysreg_el1(v, SYS_ELR);
147 	else
148 		*__vcpu_elr_el1(vcpu) = v;
149 }
150 
151 static __always_inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
152 {
153 	return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pstate;
154 }
155 
156 static __always_inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
157 {
158 	return !!(*vcpu_cpsr(vcpu) & PSR_MODE32_BIT);
159 }
160 
161 static __always_inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
162 {
163 	if (vcpu_mode_is_32bit(vcpu))
164 		return kvm_condition_valid32(vcpu);
165 
166 	return true;
167 }
168 
169 static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
170 {
171 	*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
172 }
173 
174 /*
175  * vcpu_get_reg and vcpu_set_reg should always be passed a register number
176  * coming from a read of ESR_EL2. Otherwise, it may give the wrong result on
177  * AArch32 with banked registers.
178  */
179 static __always_inline unsigned long vcpu_get_reg(const struct kvm_vcpu *vcpu,
180 					 u8 reg_num)
181 {
182 	return (reg_num == 31) ? 0 : vcpu_gp_regs(vcpu)->regs.regs[reg_num];
183 }
184 
185 static __always_inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
186 				unsigned long val)
187 {
188 	if (reg_num != 31)
189 		vcpu_gp_regs(vcpu)->regs.regs[reg_num] = val;
190 }
191 
192 static inline unsigned long vcpu_read_spsr(const struct kvm_vcpu *vcpu)
193 {
194 	if (vcpu_mode_is_32bit(vcpu))
195 		return vcpu_read_spsr32(vcpu);
196 
197 	if (vcpu->arch.sysregs_loaded_on_cpu)
198 		return read_sysreg_el1(SYS_SPSR);
199 	else
200 		return vcpu_gp_regs(vcpu)->spsr[KVM_SPSR_EL1];
201 }
202 
203 static inline void vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long v)
204 {
205 	if (vcpu_mode_is_32bit(vcpu)) {
206 		vcpu_write_spsr32(vcpu, v);
207 		return;
208 	}
209 
210 	if (vcpu->arch.sysregs_loaded_on_cpu)
211 		write_sysreg_el1(v, SYS_SPSR);
212 	else
213 		vcpu_gp_regs(vcpu)->spsr[KVM_SPSR_EL1] = v;
214 }
215 
216 /*
217  * The layout of SPSR for an AArch32 state is different when observed from an
218  * AArch64 SPSR_ELx or an AArch32 SPSR_*. This function generates the AArch32
219  * view given an AArch64 view.
220  *
221  * In ARM DDI 0487E.a see:
222  *
223  * - The AArch64 view (SPSR_EL2) in section C5.2.18, page C5-426
224  * - The AArch32 view (SPSR_abt) in section G8.2.126, page G8-6256
225  * - The AArch32 view (SPSR_und) in section G8.2.132, page G8-6280
226  *
227  * Which show the following differences:
228  *
229  * | Bit | AA64 | AA32 | Notes                       |
230  * +-----+------+------+-----------------------------|
231  * | 24  | DIT  | J    | J is RES0 in ARMv8          |
232  * | 21  | SS   | DIT  | SS doesn't exist in AArch32 |
233  *
234  * ... and all other bits are (currently) common.
235  */
236 static inline unsigned long host_spsr_to_spsr32(unsigned long spsr)
237 {
238 	const unsigned long overlap = BIT(24) | BIT(21);
239 	unsigned long dit = !!(spsr & PSR_AA32_DIT_BIT);
240 
241 	spsr &= ~overlap;
242 
243 	spsr |= dit << 21;
244 
245 	return spsr;
246 }
247 
248 static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu)
249 {
250 	u32 mode;
251 
252 	if (vcpu_mode_is_32bit(vcpu)) {
253 		mode = *vcpu_cpsr(vcpu) & PSR_AA32_MODE_MASK;
254 		return mode > PSR_AA32_MODE_USR;
255 	}
256 
257 	mode = *vcpu_cpsr(vcpu) & PSR_MODE_MASK;
258 
259 	return mode != PSR_MODE_EL0t;
260 }
261 
262 static __always_inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu)
263 {
264 	return vcpu->arch.fault.esr_el2;
265 }
266 
267 static __always_inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
268 {
269 	u32 esr = kvm_vcpu_get_hsr(vcpu);
270 
271 	if (esr & ESR_ELx_CV)
272 		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
273 
274 	return -1;
275 }
276 
277 static __always_inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
278 {
279 	return vcpu->arch.fault.far_el2;
280 }
281 
282 static __always_inline phys_addr_t kvm_vcpu_get_fault_ipa(const struct kvm_vcpu *vcpu)
283 {
284 	return ((phys_addr_t)vcpu->arch.fault.hpfar_el2 & HPFAR_MASK) << 8;
285 }
286 
287 static inline u64 kvm_vcpu_get_disr(const struct kvm_vcpu *vcpu)
288 {
289 	return vcpu->arch.fault.disr_el1;
290 }
291 
292 static inline u32 kvm_vcpu_hvc_get_imm(const struct kvm_vcpu *vcpu)
293 {
294 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_xVC_IMM_MASK;
295 }
296 
297 static __always_inline bool kvm_vcpu_dabt_isvalid(const struct kvm_vcpu *vcpu)
298 {
299 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_ISV);
300 }
301 
302 static inline unsigned long kvm_vcpu_dabt_iss_nisv_sanitized(const struct kvm_vcpu *vcpu)
303 {
304 	return kvm_vcpu_get_hsr(vcpu) & (ESR_ELx_CM | ESR_ELx_WNR | ESR_ELx_FSC);
305 }
306 
307 static inline bool kvm_vcpu_dabt_issext(const struct kvm_vcpu *vcpu)
308 {
309 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SSE);
310 }
311 
312 static inline bool kvm_vcpu_dabt_issf(const struct kvm_vcpu *vcpu)
313 {
314 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SF);
315 }
316 
317 static __always_inline int kvm_vcpu_dabt_get_rd(const struct kvm_vcpu *vcpu)
318 {
319 	return (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT;
320 }
321 
322 static __always_inline bool kvm_vcpu_dabt_iss1tw(const struct kvm_vcpu *vcpu)
323 {
324 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_S1PTW);
325 }
326 
327 static __always_inline bool kvm_vcpu_dabt_iswrite(const struct kvm_vcpu *vcpu)
328 {
329 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WNR) ||
330 		kvm_vcpu_dabt_iss1tw(vcpu); /* AF/DBM update */
331 }
332 
333 static inline bool kvm_vcpu_dabt_is_cm(const struct kvm_vcpu *vcpu)
334 {
335 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_CM);
336 }
337 
338 static __always_inline unsigned int kvm_vcpu_dabt_get_as(const struct kvm_vcpu *vcpu)
339 {
340 	return 1 << ((kvm_vcpu_get_hsr(vcpu) & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT);
341 }
342 
343 /* This one is not specific to Data Abort */
344 static __always_inline bool kvm_vcpu_trap_il_is32bit(const struct kvm_vcpu *vcpu)
345 {
346 	return !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_IL);
347 }
348 
349 static __always_inline u8 kvm_vcpu_trap_get_class(const struct kvm_vcpu *vcpu)
350 {
351 	return ESR_ELx_EC(kvm_vcpu_get_hsr(vcpu));
352 }
353 
354 static inline bool kvm_vcpu_trap_is_iabt(const struct kvm_vcpu *vcpu)
355 {
356 	return kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_IABT_LOW;
357 }
358 
359 static __always_inline u8 kvm_vcpu_trap_get_fault(const struct kvm_vcpu *vcpu)
360 {
361 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_FSC;
362 }
363 
364 static __always_inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vcpu)
365 {
366 	return kvm_vcpu_get_hsr(vcpu) & ESR_ELx_FSC_TYPE;
367 }
368 
369 static __always_inline bool kvm_vcpu_dabt_isextabt(const struct kvm_vcpu *vcpu)
370 {
371 	switch (kvm_vcpu_trap_get_fault(vcpu)) {
372 	case FSC_SEA:
373 	case FSC_SEA_TTW0:
374 	case FSC_SEA_TTW1:
375 	case FSC_SEA_TTW2:
376 	case FSC_SEA_TTW3:
377 	case FSC_SECC:
378 	case FSC_SECC_TTW0:
379 	case FSC_SECC_TTW1:
380 	case FSC_SECC_TTW2:
381 	case FSC_SECC_TTW3:
382 		return true;
383 	default:
384 		return false;
385 	}
386 }
387 
388 static __always_inline int kvm_vcpu_sys_get_rt(struct kvm_vcpu *vcpu)
389 {
390 	u32 esr = kvm_vcpu_get_hsr(vcpu);
391 	return ESR_ELx_SYS64_ISS_RT(esr);
392 }
393 
394 static inline bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
395 {
396 	if (kvm_vcpu_trap_is_iabt(vcpu))
397 		return false;
398 
399 	return kvm_vcpu_dabt_iswrite(vcpu);
400 }
401 
402 static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
403 {
404 	return vcpu_read_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
405 }
406 
407 static inline bool kvm_arm_get_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu)
408 {
409 	return vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG;
410 }
411 
412 static inline void kvm_arm_set_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu,
413 						      bool flag)
414 {
415 	if (flag)
416 		vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
417 	else
418 		vcpu->arch.workaround_flags &= ~VCPU_WORKAROUND_2_FLAG;
419 }
420 
421 static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
422 {
423 	if (vcpu_mode_is_32bit(vcpu)) {
424 		*vcpu_cpsr(vcpu) |= PSR_AA32_E_BIT;
425 	} else {
426 		u64 sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
427 		sctlr |= (1 << 25);
428 		vcpu_write_sys_reg(vcpu, sctlr, SCTLR_EL1);
429 	}
430 }
431 
432 static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
433 {
434 	if (vcpu_mode_is_32bit(vcpu))
435 		return !!(*vcpu_cpsr(vcpu) & PSR_AA32_E_BIT);
436 
437 	return !!(vcpu_read_sys_reg(vcpu, SCTLR_EL1) & (1 << 25));
438 }
439 
440 static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
441 						    unsigned long data,
442 						    unsigned int len)
443 {
444 	if (kvm_vcpu_is_be(vcpu)) {
445 		switch (len) {
446 		case 1:
447 			return data & 0xff;
448 		case 2:
449 			return be16_to_cpu(data & 0xffff);
450 		case 4:
451 			return be32_to_cpu(data & 0xffffffff);
452 		default:
453 			return be64_to_cpu(data);
454 		}
455 	} else {
456 		switch (len) {
457 		case 1:
458 			return data & 0xff;
459 		case 2:
460 			return le16_to_cpu(data & 0xffff);
461 		case 4:
462 			return le32_to_cpu(data & 0xffffffff);
463 		default:
464 			return le64_to_cpu(data);
465 		}
466 	}
467 
468 	return data;		/* Leave LE untouched */
469 }
470 
471 static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
472 						    unsigned long data,
473 						    unsigned int len)
474 {
475 	if (kvm_vcpu_is_be(vcpu)) {
476 		switch (len) {
477 		case 1:
478 			return data & 0xff;
479 		case 2:
480 			return cpu_to_be16(data & 0xffff);
481 		case 4:
482 			return cpu_to_be32(data & 0xffffffff);
483 		default:
484 			return cpu_to_be64(data);
485 		}
486 	} else {
487 		switch (len) {
488 		case 1:
489 			return data & 0xff;
490 		case 2:
491 			return cpu_to_le16(data & 0xffff);
492 		case 4:
493 			return cpu_to_le32(data & 0xffffffff);
494 		default:
495 			return cpu_to_le64(data);
496 		}
497 	}
498 
499 	return data;		/* Leave LE untouched */
500 }
501 
502 static __always_inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
503 {
504 	if (vcpu_mode_is_32bit(vcpu)) {
505 		kvm_skip_instr32(vcpu, is_wide_instr);
506 	} else {
507 		*vcpu_pc(vcpu) += 4;
508 		*vcpu_cpsr(vcpu) &= ~PSR_BTYPE_MASK;
509 	}
510 
511 	/* advance the singlestep state machine */
512 	*vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
513 }
514 
515 /*
516  * Skip an instruction which has been emulated at hyp while most guest sysregs
517  * are live.
518  */
519 static __always_inline void __hyp_text __kvm_skip_instr(struct kvm_vcpu *vcpu)
520 {
521 	*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
522 	vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(SYS_SPSR);
523 
524 	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
525 
526 	write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, SYS_SPSR);
527 	write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
528 }
529 
530 #endif /* __ARM64_KVM_EMULATE_H__ */
531