xref: /linux/arch/arm64/kvm/sys_regs.c (revision a8fe58cec351c25e09c393bf46117c0c47b5a17c)
1 /*
2  * Copyright (C) 2012,2013 - ARM Ltd
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * Derived from arch/arm/kvm/coproc.c:
6  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
7  * Authors: Rusty Russell <rusty@rustcorp.com.au>
8  *          Christoffer Dall <c.dall@virtualopensystems.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License, version 2, as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include <linux/kvm_host.h>
24 #include <linux/mm.h>
25 #include <linux/uaccess.h>
26 
27 #include <asm/cacheflush.h>
28 #include <asm/cputype.h>
29 #include <asm/debug-monitors.h>
30 #include <asm/esr.h>
31 #include <asm/kvm_arm.h>
32 #include <asm/kvm_asm.h>
33 #include <asm/kvm_coproc.h>
34 #include <asm/kvm_emulate.h>
35 #include <asm/kvm_host.h>
36 #include <asm/kvm_mmu.h>
37 
38 #include <trace/events/kvm.h>
39 
40 #include "sys_regs.h"
41 
42 #include "trace.h"
43 
44 /*
45  * All of this file is extremly similar to the ARM coproc.c, but the
46  * types are different. My gut feeling is that it should be pretty
47  * easy to merge, but that would be an ABI breakage -- again. VFP
48  * would also need to be abstracted.
49  *
50  * For AArch32, we only take care of what is being trapped. Anything
51  * that has to do with init and userspace access has to go via the
52  * 64bit interface.
53  */
54 
55 /* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
56 static u32 cache_levels;
57 
58 /* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
59 #define CSSELR_MAX 12
60 
61 /* Which cache CCSIDR represents depends on CSSELR value. */
62 static u32 get_ccsidr(u32 csselr)
63 {
64 	u32 ccsidr;
65 
66 	/* Make sure noone else changes CSSELR during this! */
67 	local_irq_disable();
68 	/* Put value into CSSELR */
69 	asm volatile("msr csselr_el1, %x0" : : "r" (csselr));
70 	isb();
71 	/* Read result out of CCSIDR */
72 	asm volatile("mrs %0, ccsidr_el1" : "=r" (ccsidr));
73 	local_irq_enable();
74 
75 	return ccsidr;
76 }
77 
78 /*
79  * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
80  */
81 static bool access_dcsw(struct kvm_vcpu *vcpu,
82 			struct sys_reg_params *p,
83 			const struct sys_reg_desc *r)
84 {
85 	if (!p->is_write)
86 		return read_from_write_only(vcpu, p);
87 
88 	kvm_set_way_flush(vcpu);
89 	return true;
90 }
91 
92 /*
93  * Generic accessor for VM registers. Only called as long as HCR_TVM
94  * is set. If the guest enables the MMU, we stop trapping the VM
95  * sys_regs and leave it in complete control of the caches.
96  */
97 static bool access_vm_reg(struct kvm_vcpu *vcpu,
98 			  struct sys_reg_params *p,
99 			  const struct sys_reg_desc *r)
100 {
101 	bool was_enabled = vcpu_has_cache_enabled(vcpu);
102 
103 	BUG_ON(!p->is_write);
104 
105 	if (!p->is_aarch32) {
106 		vcpu_sys_reg(vcpu, r->reg) = p->regval;
107 	} else {
108 		if (!p->is_32bit)
109 			vcpu_cp15_64_high(vcpu, r->reg) = upper_32_bits(p->regval);
110 		vcpu_cp15_64_low(vcpu, r->reg) = lower_32_bits(p->regval);
111 	}
112 
113 	kvm_toggle_cache(vcpu, was_enabled);
114 	return true;
115 }
116 
117 /*
118  * Trap handler for the GICv3 SGI generation system register.
119  * Forward the request to the VGIC emulation.
120  * The cp15_64 code makes sure this automatically works
121  * for both AArch64 and AArch32 accesses.
122  */
123 static bool access_gic_sgi(struct kvm_vcpu *vcpu,
124 			   struct sys_reg_params *p,
125 			   const struct sys_reg_desc *r)
126 {
127 	if (!p->is_write)
128 		return read_from_write_only(vcpu, p);
129 
130 	vgic_v3_dispatch_sgi(vcpu, p->regval);
131 
132 	return true;
133 }
134 
135 static bool trap_raz_wi(struct kvm_vcpu *vcpu,
136 			struct sys_reg_params *p,
137 			const struct sys_reg_desc *r)
138 {
139 	if (p->is_write)
140 		return ignore_write(vcpu, p);
141 	else
142 		return read_zero(vcpu, p);
143 }
144 
145 static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
146 			   struct sys_reg_params *p,
147 			   const struct sys_reg_desc *r)
148 {
149 	if (p->is_write) {
150 		return ignore_write(vcpu, p);
151 	} else {
152 		p->regval = (1 << 3);
153 		return true;
154 	}
155 }
156 
157 static bool trap_dbgauthstatus_el1(struct kvm_vcpu *vcpu,
158 				   struct sys_reg_params *p,
159 				   const struct sys_reg_desc *r)
160 {
161 	if (p->is_write) {
162 		return ignore_write(vcpu, p);
163 	} else {
164 		u32 val;
165 		asm volatile("mrs %0, dbgauthstatus_el1" : "=r" (val));
166 		p->regval = val;
167 		return true;
168 	}
169 }
170 
171 /*
172  * We want to avoid world-switching all the DBG registers all the
173  * time:
174  *
175  * - If we've touched any debug register, it is likely that we're
176  *   going to touch more of them. It then makes sense to disable the
177  *   traps and start doing the save/restore dance
178  * - If debug is active (DBG_MDSCR_KDE or DBG_MDSCR_MDE set), it is
179  *   then mandatory to save/restore the registers, as the guest
180  *   depends on them.
181  *
182  * For this, we use a DIRTY bit, indicating the guest has modified the
183  * debug registers, used as follow:
184  *
185  * On guest entry:
186  * - If the dirty bit is set (because we're coming back from trapping),
187  *   disable the traps, save host registers, restore guest registers.
188  * - If debug is actively in use (DBG_MDSCR_KDE or DBG_MDSCR_MDE set),
189  *   set the dirty bit, disable the traps, save host registers,
190  *   restore guest registers.
191  * - Otherwise, enable the traps
192  *
193  * On guest exit:
194  * - If the dirty bit is set, save guest registers, restore host
195  *   registers and clear the dirty bit. This ensure that the host can
196  *   now use the debug registers.
197  */
198 static bool trap_debug_regs(struct kvm_vcpu *vcpu,
199 			    struct sys_reg_params *p,
200 			    const struct sys_reg_desc *r)
201 {
202 	if (p->is_write) {
203 		vcpu_sys_reg(vcpu, r->reg) = p->regval;
204 		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
205 	} else {
206 		p->regval = vcpu_sys_reg(vcpu, r->reg);
207 	}
208 
209 	trace_trap_reg(__func__, r->reg, p->is_write, p->regval);
210 
211 	return true;
212 }
213 
214 /*
215  * reg_to_dbg/dbg_to_reg
216  *
217  * A 32 bit write to a debug register leave top bits alone
218  * A 32 bit read from a debug register only returns the bottom bits
219  *
220  * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the
221  * hyp.S code switches between host and guest values in future.
222  */
223 static void reg_to_dbg(struct kvm_vcpu *vcpu,
224 		       struct sys_reg_params *p,
225 		       u64 *dbg_reg)
226 {
227 	u64 val = p->regval;
228 
229 	if (p->is_32bit) {
230 		val &= 0xffffffffUL;
231 		val |= ((*dbg_reg >> 32) << 32);
232 	}
233 
234 	*dbg_reg = val;
235 	vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
236 }
237 
238 static void dbg_to_reg(struct kvm_vcpu *vcpu,
239 		       struct sys_reg_params *p,
240 		       u64 *dbg_reg)
241 {
242 	p->regval = *dbg_reg;
243 	if (p->is_32bit)
244 		p->regval &= 0xffffffffUL;
245 }
246 
247 static bool trap_bvr(struct kvm_vcpu *vcpu,
248 		     struct sys_reg_params *p,
249 		     const struct sys_reg_desc *rd)
250 {
251 	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
252 
253 	if (p->is_write)
254 		reg_to_dbg(vcpu, p, dbg_reg);
255 	else
256 		dbg_to_reg(vcpu, p, dbg_reg);
257 
258 	trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg);
259 
260 	return true;
261 }
262 
263 static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
264 		const struct kvm_one_reg *reg, void __user *uaddr)
265 {
266 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
267 
268 	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
269 		return -EFAULT;
270 	return 0;
271 }
272 
273 static int get_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
274 	const struct kvm_one_reg *reg, void __user *uaddr)
275 {
276 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
277 
278 	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
279 		return -EFAULT;
280 	return 0;
281 }
282 
283 static void reset_bvr(struct kvm_vcpu *vcpu,
284 		      const struct sys_reg_desc *rd)
285 {
286 	vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg] = rd->val;
287 }
288 
289 static bool trap_bcr(struct kvm_vcpu *vcpu,
290 		     struct sys_reg_params *p,
291 		     const struct sys_reg_desc *rd)
292 {
293 	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg];
294 
295 	if (p->is_write)
296 		reg_to_dbg(vcpu, p, dbg_reg);
297 	else
298 		dbg_to_reg(vcpu, p, dbg_reg);
299 
300 	trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg);
301 
302 	return true;
303 }
304 
305 static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
306 		const struct kvm_one_reg *reg, void __user *uaddr)
307 {
308 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg];
309 
310 	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
311 		return -EFAULT;
312 
313 	return 0;
314 }
315 
316 static int get_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
317 	const struct kvm_one_reg *reg, void __user *uaddr)
318 {
319 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg];
320 
321 	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
322 		return -EFAULT;
323 	return 0;
324 }
325 
326 static void reset_bcr(struct kvm_vcpu *vcpu,
327 		      const struct sys_reg_desc *rd)
328 {
329 	vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg] = rd->val;
330 }
331 
332 static bool trap_wvr(struct kvm_vcpu *vcpu,
333 		     struct sys_reg_params *p,
334 		     const struct sys_reg_desc *rd)
335 {
336 	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg];
337 
338 	if (p->is_write)
339 		reg_to_dbg(vcpu, p, dbg_reg);
340 	else
341 		dbg_to_reg(vcpu, p, dbg_reg);
342 
343 	trace_trap_reg(__func__, rd->reg, p->is_write,
344 		vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]);
345 
346 	return true;
347 }
348 
349 static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
350 		const struct kvm_one_reg *reg, void __user *uaddr)
351 {
352 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg];
353 
354 	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
355 		return -EFAULT;
356 	return 0;
357 }
358 
359 static int get_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
360 	const struct kvm_one_reg *reg, void __user *uaddr)
361 {
362 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg];
363 
364 	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
365 		return -EFAULT;
366 	return 0;
367 }
368 
369 static void reset_wvr(struct kvm_vcpu *vcpu,
370 		      const struct sys_reg_desc *rd)
371 {
372 	vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg] = rd->val;
373 }
374 
375 static bool trap_wcr(struct kvm_vcpu *vcpu,
376 		     struct sys_reg_params *p,
377 		     const struct sys_reg_desc *rd)
378 {
379 	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg];
380 
381 	if (p->is_write)
382 		reg_to_dbg(vcpu, p, dbg_reg);
383 	else
384 		dbg_to_reg(vcpu, p, dbg_reg);
385 
386 	trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg);
387 
388 	return true;
389 }
390 
391 static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
392 		const struct kvm_one_reg *reg, void __user *uaddr)
393 {
394 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg];
395 
396 	if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0)
397 		return -EFAULT;
398 	return 0;
399 }
400 
401 static int get_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
402 	const struct kvm_one_reg *reg, void __user *uaddr)
403 {
404 	__u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg];
405 
406 	if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0)
407 		return -EFAULT;
408 	return 0;
409 }
410 
411 static void reset_wcr(struct kvm_vcpu *vcpu,
412 		      const struct sys_reg_desc *rd)
413 {
414 	vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg] = rd->val;
415 }
416 
417 static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
418 {
419 	u64 amair;
420 
421 	asm volatile("mrs %0, amair_el1\n" : "=r" (amair));
422 	vcpu_sys_reg(vcpu, AMAIR_EL1) = amair;
423 }
424 
425 static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
426 {
427 	u64 mpidr;
428 
429 	/*
430 	 * Map the vcpu_id into the first three affinity level fields of
431 	 * the MPIDR. We limit the number of VCPUs in level 0 due to a
432 	 * limitation to 16 CPUs in that level in the ICC_SGIxR registers
433 	 * of the GICv3 to be able to address each CPU directly when
434 	 * sending IPIs.
435 	 */
436 	mpidr = (vcpu->vcpu_id & 0x0f) << MPIDR_LEVEL_SHIFT(0);
437 	mpidr |= ((vcpu->vcpu_id >> 4) & 0xff) << MPIDR_LEVEL_SHIFT(1);
438 	mpidr |= ((vcpu->vcpu_id >> 12) & 0xff) << MPIDR_LEVEL_SHIFT(2);
439 	vcpu_sys_reg(vcpu, MPIDR_EL1) = (1ULL << 31) | mpidr;
440 }
441 
442 /* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
443 #define DBG_BCR_BVR_WCR_WVR_EL1(n)					\
444 	/* DBGBVRn_EL1 */						\
445 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b100),	\
446 	  trap_bvr, reset_bvr, n, 0, get_bvr, set_bvr },		\
447 	/* DBGBCRn_EL1 */						\
448 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b101),	\
449 	  trap_bcr, reset_bcr, n, 0, get_bcr, set_bcr },		\
450 	/* DBGWVRn_EL1 */						\
451 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b110),	\
452 	  trap_wvr, reset_wvr, n, 0,  get_wvr, set_wvr },		\
453 	/* DBGWCRn_EL1 */						\
454 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111),	\
455 	  trap_wcr, reset_wcr, n, 0,  get_wcr, set_wcr }
456 
457 /*
458  * Architected system registers.
459  * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
460  *
461  * We could trap ID_DFR0 and tell the guest we don't support performance
462  * monitoring.  Unfortunately the patch to make the kernel check ID_DFR0 was
463  * NAKed, so it will read the PMCR anyway.
464  *
465  * Therefore we tell the guest we have 0 counters.  Unfortunately, we
466  * must always support PMCCNTR (the cycle counter): we just RAZ/WI for
467  * all PM registers, which doesn't crash the guest kernel at least.
468  *
469  * Debug handling: We do trap most, if not all debug related system
470  * registers. The implementation is good enough to ensure that a guest
471  * can use these with minimal performance degradation. The drawback is
472  * that we don't implement any of the external debug, none of the
473  * OSlock protocol. This should be revisited if we ever encounter a
474  * more demanding guest...
475  */
476 static const struct sys_reg_desc sys_reg_descs[] = {
477 	/* DC ISW */
478 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b0110), Op2(0b010),
479 	  access_dcsw },
480 	/* DC CSW */
481 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1010), Op2(0b010),
482 	  access_dcsw },
483 	/* DC CISW */
484 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b010),
485 	  access_dcsw },
486 
487 	DBG_BCR_BVR_WCR_WVR_EL1(0),
488 	DBG_BCR_BVR_WCR_WVR_EL1(1),
489 	/* MDCCINT_EL1 */
490 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b000),
491 	  trap_debug_regs, reset_val, MDCCINT_EL1, 0 },
492 	/* MDSCR_EL1 */
493 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b010),
494 	  trap_debug_regs, reset_val, MDSCR_EL1, 0 },
495 	DBG_BCR_BVR_WCR_WVR_EL1(2),
496 	DBG_BCR_BVR_WCR_WVR_EL1(3),
497 	DBG_BCR_BVR_WCR_WVR_EL1(4),
498 	DBG_BCR_BVR_WCR_WVR_EL1(5),
499 	DBG_BCR_BVR_WCR_WVR_EL1(6),
500 	DBG_BCR_BVR_WCR_WVR_EL1(7),
501 	DBG_BCR_BVR_WCR_WVR_EL1(8),
502 	DBG_BCR_BVR_WCR_WVR_EL1(9),
503 	DBG_BCR_BVR_WCR_WVR_EL1(10),
504 	DBG_BCR_BVR_WCR_WVR_EL1(11),
505 	DBG_BCR_BVR_WCR_WVR_EL1(12),
506 	DBG_BCR_BVR_WCR_WVR_EL1(13),
507 	DBG_BCR_BVR_WCR_WVR_EL1(14),
508 	DBG_BCR_BVR_WCR_WVR_EL1(15),
509 
510 	/* MDRAR_EL1 */
511 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
512 	  trap_raz_wi },
513 	/* OSLAR_EL1 */
514 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b100),
515 	  trap_raz_wi },
516 	/* OSLSR_EL1 */
517 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0001), Op2(0b100),
518 	  trap_oslsr_el1 },
519 	/* OSDLR_EL1 */
520 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0011), Op2(0b100),
521 	  trap_raz_wi },
522 	/* DBGPRCR_EL1 */
523 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0100), Op2(0b100),
524 	  trap_raz_wi },
525 	/* DBGCLAIMSET_EL1 */
526 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1000), Op2(0b110),
527 	  trap_raz_wi },
528 	/* DBGCLAIMCLR_EL1 */
529 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1001), Op2(0b110),
530 	  trap_raz_wi },
531 	/* DBGAUTHSTATUS_EL1 */
532 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b110),
533 	  trap_dbgauthstatus_el1 },
534 
535 	/* MDCCSR_EL1 */
536 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0001), Op2(0b000),
537 	  trap_raz_wi },
538 	/* DBGDTR_EL0 */
539 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0100), Op2(0b000),
540 	  trap_raz_wi },
541 	/* DBGDTR[TR]X_EL0 */
542 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0101), Op2(0b000),
543 	  trap_raz_wi },
544 
545 	/* DBGVCR32_EL2 */
546 	{ Op0(0b10), Op1(0b100), CRn(0b0000), CRm(0b0111), Op2(0b000),
547 	  NULL, reset_val, DBGVCR32_EL2, 0 },
548 
549 	/* MPIDR_EL1 */
550 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b101),
551 	  NULL, reset_mpidr, MPIDR_EL1 },
552 	/* SCTLR_EL1 */
553 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
554 	  access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 },
555 	/* CPACR_EL1 */
556 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b010),
557 	  NULL, reset_val, CPACR_EL1, 0 },
558 	/* TTBR0_EL1 */
559 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b000),
560 	  access_vm_reg, reset_unknown, TTBR0_EL1 },
561 	/* TTBR1_EL1 */
562 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b001),
563 	  access_vm_reg, reset_unknown, TTBR1_EL1 },
564 	/* TCR_EL1 */
565 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b010),
566 	  access_vm_reg, reset_val, TCR_EL1, 0 },
567 
568 	/* AFSR0_EL1 */
569 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b000),
570 	  access_vm_reg, reset_unknown, AFSR0_EL1 },
571 	/* AFSR1_EL1 */
572 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b001),
573 	  access_vm_reg, reset_unknown, AFSR1_EL1 },
574 	/* ESR_EL1 */
575 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0010), Op2(0b000),
576 	  access_vm_reg, reset_unknown, ESR_EL1 },
577 	/* FAR_EL1 */
578 	{ Op0(0b11), Op1(0b000), CRn(0b0110), CRm(0b0000), Op2(0b000),
579 	  access_vm_reg, reset_unknown, FAR_EL1 },
580 	/* PAR_EL1 */
581 	{ Op0(0b11), Op1(0b000), CRn(0b0111), CRm(0b0100), Op2(0b000),
582 	  NULL, reset_unknown, PAR_EL1 },
583 
584 	/* PMINTENSET_EL1 */
585 	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b001),
586 	  trap_raz_wi },
587 	/* PMINTENCLR_EL1 */
588 	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b010),
589 	  trap_raz_wi },
590 
591 	/* MAIR_EL1 */
592 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0010), Op2(0b000),
593 	  access_vm_reg, reset_unknown, MAIR_EL1 },
594 	/* AMAIR_EL1 */
595 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0011), Op2(0b000),
596 	  access_vm_reg, reset_amair_el1, AMAIR_EL1 },
597 
598 	/* VBAR_EL1 */
599 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b0000), Op2(0b000),
600 	  NULL, reset_val, VBAR_EL1, 0 },
601 
602 	/* ICC_SGI1R_EL1 */
603 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b1011), Op2(0b101),
604 	  access_gic_sgi },
605 	/* ICC_SRE_EL1 */
606 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b1100), Op2(0b101),
607 	  trap_raz_wi },
608 
609 	/* CONTEXTIDR_EL1 */
610 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b001),
611 	  access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
612 	/* TPIDR_EL1 */
613 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b100),
614 	  NULL, reset_unknown, TPIDR_EL1 },
615 
616 	/* CNTKCTL_EL1 */
617 	{ Op0(0b11), Op1(0b000), CRn(0b1110), CRm(0b0001), Op2(0b000),
618 	  NULL, reset_val, CNTKCTL_EL1, 0},
619 
620 	/* CSSELR_EL1 */
621 	{ Op0(0b11), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
622 	  NULL, reset_unknown, CSSELR_EL1 },
623 
624 	/* PMCR_EL0 */
625 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b000),
626 	  trap_raz_wi },
627 	/* PMCNTENSET_EL0 */
628 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b001),
629 	  trap_raz_wi },
630 	/* PMCNTENCLR_EL0 */
631 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b010),
632 	  trap_raz_wi },
633 	/* PMOVSCLR_EL0 */
634 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
635 	  trap_raz_wi },
636 	/* PMSWINC_EL0 */
637 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
638 	  trap_raz_wi },
639 	/* PMSELR_EL0 */
640 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b101),
641 	  trap_raz_wi },
642 	/* PMCEID0_EL0 */
643 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b110),
644 	  trap_raz_wi },
645 	/* PMCEID1_EL0 */
646 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b111),
647 	  trap_raz_wi },
648 	/* PMCCNTR_EL0 */
649 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
650 	  trap_raz_wi },
651 	/* PMXEVTYPER_EL0 */
652 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
653 	  trap_raz_wi },
654 	/* PMXEVCNTR_EL0 */
655 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
656 	  trap_raz_wi },
657 	/* PMUSERENR_EL0 */
658 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b000),
659 	  trap_raz_wi },
660 	/* PMOVSSET_EL0 */
661 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b011),
662 	  trap_raz_wi },
663 
664 	/* TPIDR_EL0 */
665 	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
666 	  NULL, reset_unknown, TPIDR_EL0 },
667 	/* TPIDRRO_EL0 */
668 	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
669 	  NULL, reset_unknown, TPIDRRO_EL0 },
670 
671 	/* DACR32_EL2 */
672 	{ Op0(0b11), Op1(0b100), CRn(0b0011), CRm(0b0000), Op2(0b000),
673 	  NULL, reset_unknown, DACR32_EL2 },
674 	/* IFSR32_EL2 */
675 	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0000), Op2(0b001),
676 	  NULL, reset_unknown, IFSR32_EL2 },
677 	/* FPEXC32_EL2 */
678 	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0011), Op2(0b000),
679 	  NULL, reset_val, FPEXC32_EL2, 0x70 },
680 };
681 
682 static bool trap_dbgidr(struct kvm_vcpu *vcpu,
683 			struct sys_reg_params *p,
684 			const struct sys_reg_desc *r)
685 {
686 	if (p->is_write) {
687 		return ignore_write(vcpu, p);
688 	} else {
689 		u64 dfr = read_system_reg(SYS_ID_AA64DFR0_EL1);
690 		u64 pfr = read_system_reg(SYS_ID_AA64PFR0_EL1);
691 		u32 el3 = !!cpuid_feature_extract_field(pfr, ID_AA64PFR0_EL3_SHIFT);
692 
693 		p->regval = ((((dfr >> ID_AA64DFR0_WRPS_SHIFT) & 0xf) << 28) |
694 			     (((dfr >> ID_AA64DFR0_BRPS_SHIFT) & 0xf) << 24) |
695 			     (((dfr >> ID_AA64DFR0_CTX_CMPS_SHIFT) & 0xf) << 20)
696 			     | (6 << 16) | (el3 << 14) | (el3 << 12));
697 		return true;
698 	}
699 }
700 
701 static bool trap_debug32(struct kvm_vcpu *vcpu,
702 			 struct sys_reg_params *p,
703 			 const struct sys_reg_desc *r)
704 {
705 	if (p->is_write) {
706 		vcpu_cp14(vcpu, r->reg) = p->regval;
707 		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
708 	} else {
709 		p->regval = vcpu_cp14(vcpu, r->reg);
710 	}
711 
712 	return true;
713 }
714 
715 /* AArch32 debug register mappings
716  *
717  * AArch32 DBGBVRn is mapped to DBGBVRn_EL1[31:0]
718  * AArch32 DBGBXVRn is mapped to DBGBVRn_EL1[63:32]
719  *
720  * All control registers and watchpoint value registers are mapped to
721  * the lower 32 bits of their AArch64 equivalents. We share the trap
722  * handlers with the above AArch64 code which checks what mode the
723  * system is in.
724  */
725 
726 static bool trap_xvr(struct kvm_vcpu *vcpu,
727 		     struct sys_reg_params *p,
728 		     const struct sys_reg_desc *rd)
729 {
730 	u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg];
731 
732 	if (p->is_write) {
733 		u64 val = *dbg_reg;
734 
735 		val &= 0xffffffffUL;
736 		val |= p->regval << 32;
737 		*dbg_reg = val;
738 
739 		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
740 	} else {
741 		p->regval = *dbg_reg >> 32;
742 	}
743 
744 	trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg);
745 
746 	return true;
747 }
748 
749 #define DBG_BCR_BVR_WCR_WVR(n)						\
750 	/* DBGBVRn */							\
751 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_bvr, NULL, n }, 	\
752 	/* DBGBCRn */							\
753 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_bcr, NULL, n },	\
754 	/* DBGWVRn */							\
755 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_wvr, NULL, n },	\
756 	/* DBGWCRn */							\
757 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_wcr, NULL, n }
758 
759 #define DBGBXVR(n)							\
760 	{ Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_xvr, NULL, n }
761 
762 /*
763  * Trapped cp14 registers. We generally ignore most of the external
764  * debug, on the principle that they don't really make sense to a
765  * guest. Revisit this one day, would this principle change.
766  */
767 static const struct sys_reg_desc cp14_regs[] = {
768 	/* DBGIDR */
769 	{ Op1( 0), CRn( 0), CRm( 0), Op2( 0), trap_dbgidr },
770 	/* DBGDTRRXext */
771 	{ Op1( 0), CRn( 0), CRm( 0), Op2( 2), trap_raz_wi },
772 
773 	DBG_BCR_BVR_WCR_WVR(0),
774 	/* DBGDSCRint */
775 	{ Op1( 0), CRn( 0), CRm( 1), Op2( 0), trap_raz_wi },
776 	DBG_BCR_BVR_WCR_WVR(1),
777 	/* DBGDCCINT */
778 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), trap_debug32 },
779 	/* DBGDSCRext */
780 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 2), trap_debug32 },
781 	DBG_BCR_BVR_WCR_WVR(2),
782 	/* DBGDTR[RT]Xint */
783 	{ Op1( 0), CRn( 0), CRm( 3), Op2( 0), trap_raz_wi },
784 	/* DBGDTR[RT]Xext */
785 	{ Op1( 0), CRn( 0), CRm( 3), Op2( 2), trap_raz_wi },
786 	DBG_BCR_BVR_WCR_WVR(3),
787 	DBG_BCR_BVR_WCR_WVR(4),
788 	DBG_BCR_BVR_WCR_WVR(5),
789 	/* DBGWFAR */
790 	{ Op1( 0), CRn( 0), CRm( 6), Op2( 0), trap_raz_wi },
791 	/* DBGOSECCR */
792 	{ Op1( 0), CRn( 0), CRm( 6), Op2( 2), trap_raz_wi },
793 	DBG_BCR_BVR_WCR_WVR(6),
794 	/* DBGVCR */
795 	{ Op1( 0), CRn( 0), CRm( 7), Op2( 0), trap_debug32 },
796 	DBG_BCR_BVR_WCR_WVR(7),
797 	DBG_BCR_BVR_WCR_WVR(8),
798 	DBG_BCR_BVR_WCR_WVR(9),
799 	DBG_BCR_BVR_WCR_WVR(10),
800 	DBG_BCR_BVR_WCR_WVR(11),
801 	DBG_BCR_BVR_WCR_WVR(12),
802 	DBG_BCR_BVR_WCR_WVR(13),
803 	DBG_BCR_BVR_WCR_WVR(14),
804 	DBG_BCR_BVR_WCR_WVR(15),
805 
806 	/* DBGDRAR (32bit) */
807 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), trap_raz_wi },
808 
809 	DBGBXVR(0),
810 	/* DBGOSLAR */
811 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 4), trap_raz_wi },
812 	DBGBXVR(1),
813 	/* DBGOSLSR */
814 	{ Op1( 0), CRn( 1), CRm( 1), Op2( 4), trap_oslsr_el1 },
815 	DBGBXVR(2),
816 	DBGBXVR(3),
817 	/* DBGOSDLR */
818 	{ Op1( 0), CRn( 1), CRm( 3), Op2( 4), trap_raz_wi },
819 	DBGBXVR(4),
820 	/* DBGPRCR */
821 	{ Op1( 0), CRn( 1), CRm( 4), Op2( 4), trap_raz_wi },
822 	DBGBXVR(5),
823 	DBGBXVR(6),
824 	DBGBXVR(7),
825 	DBGBXVR(8),
826 	DBGBXVR(9),
827 	DBGBXVR(10),
828 	DBGBXVR(11),
829 	DBGBXVR(12),
830 	DBGBXVR(13),
831 	DBGBXVR(14),
832 	DBGBXVR(15),
833 
834 	/* DBGDSAR (32bit) */
835 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), trap_raz_wi },
836 
837 	/* DBGDEVID2 */
838 	{ Op1( 0), CRn( 7), CRm( 0), Op2( 7), trap_raz_wi },
839 	/* DBGDEVID1 */
840 	{ Op1( 0), CRn( 7), CRm( 1), Op2( 7), trap_raz_wi },
841 	/* DBGDEVID */
842 	{ Op1( 0), CRn( 7), CRm( 2), Op2( 7), trap_raz_wi },
843 	/* DBGCLAIMSET */
844 	{ Op1( 0), CRn( 7), CRm( 8), Op2( 6), trap_raz_wi },
845 	/* DBGCLAIMCLR */
846 	{ Op1( 0), CRn( 7), CRm( 9), Op2( 6), trap_raz_wi },
847 	/* DBGAUTHSTATUS */
848 	{ Op1( 0), CRn( 7), CRm(14), Op2( 6), trap_dbgauthstatus_el1 },
849 };
850 
851 /* Trapped cp14 64bit registers */
852 static const struct sys_reg_desc cp14_64_regs[] = {
853 	/* DBGDRAR (64bit) */
854 	{ Op1( 0), CRm( 1), .access = trap_raz_wi },
855 
856 	/* DBGDSAR (64bit) */
857 	{ Op1( 0), CRm( 2), .access = trap_raz_wi },
858 };
859 
860 /*
861  * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
862  * depending on the way they are accessed (as a 32bit or a 64bit
863  * register).
864  */
865 static const struct sys_reg_desc cp15_regs[] = {
866 	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
867 
868 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_vm_reg, NULL, c1_SCTLR },
869 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
870 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
871 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
872 	{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
873 	{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
874 	{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },
875 	{ Op1( 0), CRn( 5), CRm( 1), Op2( 0), access_vm_reg, NULL, c5_ADFSR },
876 	{ Op1( 0), CRn( 5), CRm( 1), Op2( 1), access_vm_reg, NULL, c5_AIFSR },
877 	{ Op1( 0), CRn( 6), CRm( 0), Op2( 0), access_vm_reg, NULL, c6_DFAR },
878 	{ Op1( 0), CRn( 6), CRm( 0), Op2( 2), access_vm_reg, NULL, c6_IFAR },
879 
880 	/*
881 	 * DC{C,I,CI}SW operations:
882 	 */
883 	{ Op1( 0), CRn( 7), CRm( 6), Op2( 2), access_dcsw },
884 	{ Op1( 0), CRn( 7), CRm(10), Op2( 2), access_dcsw },
885 	{ Op1( 0), CRn( 7), CRm(14), Op2( 2), access_dcsw },
886 
887 	/* PMU */
888 	{ Op1( 0), CRn( 9), CRm(12), Op2( 0), trap_raz_wi },
889 	{ Op1( 0), CRn( 9), CRm(12), Op2( 1), trap_raz_wi },
890 	{ Op1( 0), CRn( 9), CRm(12), Op2( 2), trap_raz_wi },
891 	{ Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
892 	{ Op1( 0), CRn( 9), CRm(12), Op2( 5), trap_raz_wi },
893 	{ Op1( 0), CRn( 9), CRm(12), Op2( 6), trap_raz_wi },
894 	{ Op1( 0), CRn( 9), CRm(12), Op2( 7), trap_raz_wi },
895 	{ Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
896 	{ Op1( 0), CRn( 9), CRm(13), Op2( 1), trap_raz_wi },
897 	{ Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
898 	{ Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
899 	{ Op1( 0), CRn( 9), CRm(14), Op2( 1), trap_raz_wi },
900 	{ Op1( 0), CRn( 9), CRm(14), Op2( 2), trap_raz_wi },
901 
902 	{ Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
903 	{ Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
904 	{ Op1( 0), CRn(10), CRm( 3), Op2( 0), access_vm_reg, NULL, c10_AMAIR0 },
905 	{ Op1( 0), CRn(10), CRm( 3), Op2( 1), access_vm_reg, NULL, c10_AMAIR1 },
906 
907 	/* ICC_SRE */
908 	{ Op1( 0), CRn(12), CRm(12), Op2( 5), trap_raz_wi },
909 
910 	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
911 };
912 
913 static const struct sys_reg_desc cp15_64_regs[] = {
914 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
915 	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
916 	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
917 };
918 
919 /* Target specific emulation tables */
920 static struct kvm_sys_reg_target_table *target_tables[KVM_ARM_NUM_TARGETS];
921 
922 void kvm_register_target_sys_reg_table(unsigned int target,
923 				       struct kvm_sys_reg_target_table *table)
924 {
925 	target_tables[target] = table;
926 }
927 
928 /* Get specific register table for this target. */
929 static const struct sys_reg_desc *get_target_table(unsigned target,
930 						   bool mode_is_64,
931 						   size_t *num)
932 {
933 	struct kvm_sys_reg_target_table *table;
934 
935 	table = target_tables[target];
936 	if (mode_is_64) {
937 		*num = table->table64.num;
938 		return table->table64.table;
939 	} else {
940 		*num = table->table32.num;
941 		return table->table32.table;
942 	}
943 }
944 
945 static const struct sys_reg_desc *find_reg(const struct sys_reg_params *params,
946 					 const struct sys_reg_desc table[],
947 					 unsigned int num)
948 {
949 	unsigned int i;
950 
951 	for (i = 0; i < num; i++) {
952 		const struct sys_reg_desc *r = &table[i];
953 
954 		if (params->Op0 != r->Op0)
955 			continue;
956 		if (params->Op1 != r->Op1)
957 			continue;
958 		if (params->CRn != r->CRn)
959 			continue;
960 		if (params->CRm != r->CRm)
961 			continue;
962 		if (params->Op2 != r->Op2)
963 			continue;
964 
965 		return r;
966 	}
967 	return NULL;
968 }
969 
970 int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
971 {
972 	kvm_inject_undefined(vcpu);
973 	return 1;
974 }
975 
976 /*
977  * emulate_cp --  tries to match a sys_reg access in a handling table, and
978  *                call the corresponding trap handler.
979  *
980  * @params: pointer to the descriptor of the access
981  * @table: array of trap descriptors
982  * @num: size of the trap descriptor array
983  *
984  * Return 0 if the access has been handled, and -1 if not.
985  */
986 static int emulate_cp(struct kvm_vcpu *vcpu,
987 		      struct sys_reg_params *params,
988 		      const struct sys_reg_desc *table,
989 		      size_t num)
990 {
991 	const struct sys_reg_desc *r;
992 
993 	if (!table)
994 		return -1;	/* Not handled */
995 
996 	r = find_reg(params, table, num);
997 
998 	if (r) {
999 		/*
1000 		 * Not having an accessor means that we have
1001 		 * configured a trap that we don't know how to
1002 		 * handle. This certainly qualifies as a gross bug
1003 		 * that should be fixed right away.
1004 		 */
1005 		BUG_ON(!r->access);
1006 
1007 		if (likely(r->access(vcpu, params, r))) {
1008 			/* Skip instruction, since it was emulated */
1009 			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
1010 		}
1011 
1012 		/* Handled */
1013 		return 0;
1014 	}
1015 
1016 	/* Not handled */
1017 	return -1;
1018 }
1019 
1020 static void unhandled_cp_access(struct kvm_vcpu *vcpu,
1021 				struct sys_reg_params *params)
1022 {
1023 	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
1024 	int cp;
1025 
1026 	switch(hsr_ec) {
1027 	case ESR_ELx_EC_CP15_32:
1028 	case ESR_ELx_EC_CP15_64:
1029 		cp = 15;
1030 		break;
1031 	case ESR_ELx_EC_CP14_MR:
1032 	case ESR_ELx_EC_CP14_64:
1033 		cp = 14;
1034 		break;
1035 	default:
1036 		WARN_ON((cp = -1));
1037 	}
1038 
1039 	kvm_err("Unsupported guest CP%d access at: %08lx\n",
1040 		cp, *vcpu_pc(vcpu));
1041 	print_sys_reg_instr(params);
1042 	kvm_inject_undefined(vcpu);
1043 }
1044 
1045 /**
1046  * kvm_handle_cp_64 -- handles a mrrc/mcrr trap on a guest CP15 access
1047  * @vcpu: The VCPU pointer
1048  * @run:  The kvm_run struct
1049  */
1050 static int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
1051 			    const struct sys_reg_desc *global,
1052 			    size_t nr_global,
1053 			    const struct sys_reg_desc *target_specific,
1054 			    size_t nr_specific)
1055 {
1056 	struct sys_reg_params params;
1057 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
1058 	int Rt = (hsr >> 5) & 0xf;
1059 	int Rt2 = (hsr >> 10) & 0xf;
1060 
1061 	params.is_aarch32 = true;
1062 	params.is_32bit = false;
1063 	params.CRm = (hsr >> 1) & 0xf;
1064 	params.is_write = ((hsr & 1) == 0);
1065 
1066 	params.Op0 = 0;
1067 	params.Op1 = (hsr >> 16) & 0xf;
1068 	params.Op2 = 0;
1069 	params.CRn = 0;
1070 
1071 	/*
1072 	 * Make a 64-bit value out of Rt and Rt2. As we use the same trap
1073 	 * backends between AArch32 and AArch64, we get away with it.
1074 	 */
1075 	if (params.is_write) {
1076 		params.regval = vcpu_get_reg(vcpu, Rt) & 0xffffffff;
1077 		params.regval |= vcpu_get_reg(vcpu, Rt2) << 32;
1078 	}
1079 
1080 	if (!emulate_cp(vcpu, &params, target_specific, nr_specific))
1081 		goto out;
1082 	if (!emulate_cp(vcpu, &params, global, nr_global))
1083 		goto out;
1084 
1085 	unhandled_cp_access(vcpu, &params);
1086 
1087 out:
1088 	/* Split up the value between registers for the read side */
1089 	if (!params.is_write) {
1090 		vcpu_set_reg(vcpu, Rt, lower_32_bits(params.regval));
1091 		vcpu_set_reg(vcpu, Rt2, upper_32_bits(params.regval));
1092 	}
1093 
1094 	return 1;
1095 }
1096 
1097 /**
1098  * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
1099  * @vcpu: The VCPU pointer
1100  * @run:  The kvm_run struct
1101  */
1102 static int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
1103 			    const struct sys_reg_desc *global,
1104 			    size_t nr_global,
1105 			    const struct sys_reg_desc *target_specific,
1106 			    size_t nr_specific)
1107 {
1108 	struct sys_reg_params params;
1109 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
1110 	int Rt  = (hsr >> 5) & 0xf;
1111 
1112 	params.is_aarch32 = true;
1113 	params.is_32bit = true;
1114 	params.CRm = (hsr >> 1) & 0xf;
1115 	params.regval = vcpu_get_reg(vcpu, Rt);
1116 	params.is_write = ((hsr & 1) == 0);
1117 	params.CRn = (hsr >> 10) & 0xf;
1118 	params.Op0 = 0;
1119 	params.Op1 = (hsr >> 14) & 0x7;
1120 	params.Op2 = (hsr >> 17) & 0x7;
1121 
1122 	if (!emulate_cp(vcpu, &params, target_specific, nr_specific) ||
1123 	    !emulate_cp(vcpu, &params, global, nr_global)) {
1124 		if (!params.is_write)
1125 			vcpu_set_reg(vcpu, Rt, params.regval);
1126 		return 1;
1127 	}
1128 
1129 	unhandled_cp_access(vcpu, &params);
1130 	return 1;
1131 }
1132 
1133 int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
1134 {
1135 	const struct sys_reg_desc *target_specific;
1136 	size_t num;
1137 
1138 	target_specific = get_target_table(vcpu->arch.target, false, &num);
1139 	return kvm_handle_cp_64(vcpu,
1140 				cp15_64_regs, ARRAY_SIZE(cp15_64_regs),
1141 				target_specific, num);
1142 }
1143 
1144 int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
1145 {
1146 	const struct sys_reg_desc *target_specific;
1147 	size_t num;
1148 
1149 	target_specific = get_target_table(vcpu->arch.target, false, &num);
1150 	return kvm_handle_cp_32(vcpu,
1151 				cp15_regs, ARRAY_SIZE(cp15_regs),
1152 				target_specific, num);
1153 }
1154 
1155 int kvm_handle_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
1156 {
1157 	return kvm_handle_cp_64(vcpu,
1158 				cp14_64_regs, ARRAY_SIZE(cp14_64_regs),
1159 				NULL, 0);
1160 }
1161 
1162 int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
1163 {
1164 	return kvm_handle_cp_32(vcpu,
1165 				cp14_regs, ARRAY_SIZE(cp14_regs),
1166 				NULL, 0);
1167 }
1168 
1169 static int emulate_sys_reg(struct kvm_vcpu *vcpu,
1170 			   struct sys_reg_params *params)
1171 {
1172 	size_t num;
1173 	const struct sys_reg_desc *table, *r;
1174 
1175 	table = get_target_table(vcpu->arch.target, true, &num);
1176 
1177 	/* Search target-specific then generic table. */
1178 	r = find_reg(params, table, num);
1179 	if (!r)
1180 		r = find_reg(params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
1181 
1182 	if (likely(r)) {
1183 		/*
1184 		 * Not having an accessor means that we have
1185 		 * configured a trap that we don't know how to
1186 		 * handle. This certainly qualifies as a gross bug
1187 		 * that should be fixed right away.
1188 		 */
1189 		BUG_ON(!r->access);
1190 
1191 		if (likely(r->access(vcpu, params, r))) {
1192 			/* Skip instruction, since it was emulated */
1193 			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
1194 			return 1;
1195 		}
1196 		/* If access function fails, it should complain. */
1197 	} else {
1198 		kvm_err("Unsupported guest sys_reg access at: %lx\n",
1199 			*vcpu_pc(vcpu));
1200 		print_sys_reg_instr(params);
1201 	}
1202 	kvm_inject_undefined(vcpu);
1203 	return 1;
1204 }
1205 
1206 static void reset_sys_reg_descs(struct kvm_vcpu *vcpu,
1207 			      const struct sys_reg_desc *table, size_t num)
1208 {
1209 	unsigned long i;
1210 
1211 	for (i = 0; i < num; i++)
1212 		if (table[i].reset)
1213 			table[i].reset(vcpu, &table[i]);
1214 }
1215 
1216 /**
1217  * kvm_handle_sys_reg -- handles a mrs/msr trap on a guest sys_reg access
1218  * @vcpu: The VCPU pointer
1219  * @run:  The kvm_run struct
1220  */
1221 int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run)
1222 {
1223 	struct sys_reg_params params;
1224 	unsigned long esr = kvm_vcpu_get_hsr(vcpu);
1225 	int Rt = (esr >> 5) & 0x1f;
1226 	int ret;
1227 
1228 	trace_kvm_handle_sys_reg(esr);
1229 
1230 	params.is_aarch32 = false;
1231 	params.is_32bit = false;
1232 	params.Op0 = (esr >> 20) & 3;
1233 	params.Op1 = (esr >> 14) & 0x7;
1234 	params.CRn = (esr >> 10) & 0xf;
1235 	params.CRm = (esr >> 1) & 0xf;
1236 	params.Op2 = (esr >> 17) & 0x7;
1237 	params.regval = vcpu_get_reg(vcpu, Rt);
1238 	params.is_write = !(esr & 1);
1239 
1240 	ret = emulate_sys_reg(vcpu, &params);
1241 
1242 	if (!params.is_write)
1243 		vcpu_set_reg(vcpu, Rt, params.regval);
1244 	return ret;
1245 }
1246 
1247 /******************************************************************************
1248  * Userspace API
1249  *****************************************************************************/
1250 
1251 static bool index_to_params(u64 id, struct sys_reg_params *params)
1252 {
1253 	switch (id & KVM_REG_SIZE_MASK) {
1254 	case KVM_REG_SIZE_U64:
1255 		/* Any unused index bits means it's not valid. */
1256 		if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
1257 			      | KVM_REG_ARM_COPROC_MASK
1258 			      | KVM_REG_ARM64_SYSREG_OP0_MASK
1259 			      | KVM_REG_ARM64_SYSREG_OP1_MASK
1260 			      | KVM_REG_ARM64_SYSREG_CRN_MASK
1261 			      | KVM_REG_ARM64_SYSREG_CRM_MASK
1262 			      | KVM_REG_ARM64_SYSREG_OP2_MASK))
1263 			return false;
1264 		params->Op0 = ((id & KVM_REG_ARM64_SYSREG_OP0_MASK)
1265 			       >> KVM_REG_ARM64_SYSREG_OP0_SHIFT);
1266 		params->Op1 = ((id & KVM_REG_ARM64_SYSREG_OP1_MASK)
1267 			       >> KVM_REG_ARM64_SYSREG_OP1_SHIFT);
1268 		params->CRn = ((id & KVM_REG_ARM64_SYSREG_CRN_MASK)
1269 			       >> KVM_REG_ARM64_SYSREG_CRN_SHIFT);
1270 		params->CRm = ((id & KVM_REG_ARM64_SYSREG_CRM_MASK)
1271 			       >> KVM_REG_ARM64_SYSREG_CRM_SHIFT);
1272 		params->Op2 = ((id & KVM_REG_ARM64_SYSREG_OP2_MASK)
1273 			       >> KVM_REG_ARM64_SYSREG_OP2_SHIFT);
1274 		return true;
1275 	default:
1276 		return false;
1277 	}
1278 }
1279 
1280 /* Decode an index value, and find the sys_reg_desc entry. */
1281 static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
1282 						    u64 id)
1283 {
1284 	size_t num;
1285 	const struct sys_reg_desc *table, *r;
1286 	struct sys_reg_params params;
1287 
1288 	/* We only do sys_reg for now. */
1289 	if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG)
1290 		return NULL;
1291 
1292 	if (!index_to_params(id, &params))
1293 		return NULL;
1294 
1295 	table = get_target_table(vcpu->arch.target, true, &num);
1296 	r = find_reg(&params, table, num);
1297 	if (!r)
1298 		r = find_reg(&params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
1299 
1300 	/* Not saved in the sys_reg array? */
1301 	if (r && !r->reg)
1302 		r = NULL;
1303 
1304 	return r;
1305 }
1306 
1307 /*
1308  * These are the invariant sys_reg registers: we let the guest see the
1309  * host versions of these, so they're part of the guest state.
1310  *
1311  * A future CPU may provide a mechanism to present different values to
1312  * the guest, or a future kvm may trap them.
1313  */
1314 
1315 #define FUNCTION_INVARIANT(reg)						\
1316 	static void get_##reg(struct kvm_vcpu *v,			\
1317 			      const struct sys_reg_desc *r)		\
1318 	{								\
1319 		u64 val;						\
1320 									\
1321 		asm volatile("mrs %0, " __stringify(reg) "\n"		\
1322 			     : "=r" (val));				\
1323 		((struct sys_reg_desc *)r)->val = val;			\
1324 	}
1325 
1326 FUNCTION_INVARIANT(midr_el1)
1327 FUNCTION_INVARIANT(ctr_el0)
1328 FUNCTION_INVARIANT(revidr_el1)
1329 FUNCTION_INVARIANT(id_pfr0_el1)
1330 FUNCTION_INVARIANT(id_pfr1_el1)
1331 FUNCTION_INVARIANT(id_dfr0_el1)
1332 FUNCTION_INVARIANT(id_afr0_el1)
1333 FUNCTION_INVARIANT(id_mmfr0_el1)
1334 FUNCTION_INVARIANT(id_mmfr1_el1)
1335 FUNCTION_INVARIANT(id_mmfr2_el1)
1336 FUNCTION_INVARIANT(id_mmfr3_el1)
1337 FUNCTION_INVARIANT(id_isar0_el1)
1338 FUNCTION_INVARIANT(id_isar1_el1)
1339 FUNCTION_INVARIANT(id_isar2_el1)
1340 FUNCTION_INVARIANT(id_isar3_el1)
1341 FUNCTION_INVARIANT(id_isar4_el1)
1342 FUNCTION_INVARIANT(id_isar5_el1)
1343 FUNCTION_INVARIANT(clidr_el1)
1344 FUNCTION_INVARIANT(aidr_el1)
1345 
1346 /* ->val is filled in by kvm_sys_reg_table_init() */
1347 static struct sys_reg_desc invariant_sys_regs[] = {
1348 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b000),
1349 	  NULL, get_midr_el1 },
1350 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b110),
1351 	  NULL, get_revidr_el1 },
1352 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b000),
1353 	  NULL, get_id_pfr0_el1 },
1354 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b001),
1355 	  NULL, get_id_pfr1_el1 },
1356 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b010),
1357 	  NULL, get_id_dfr0_el1 },
1358 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b011),
1359 	  NULL, get_id_afr0_el1 },
1360 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b100),
1361 	  NULL, get_id_mmfr0_el1 },
1362 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b101),
1363 	  NULL, get_id_mmfr1_el1 },
1364 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b110),
1365 	  NULL, get_id_mmfr2_el1 },
1366 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b111),
1367 	  NULL, get_id_mmfr3_el1 },
1368 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b000),
1369 	  NULL, get_id_isar0_el1 },
1370 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b001),
1371 	  NULL, get_id_isar1_el1 },
1372 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b010),
1373 	  NULL, get_id_isar2_el1 },
1374 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b011),
1375 	  NULL, get_id_isar3_el1 },
1376 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b100),
1377 	  NULL, get_id_isar4_el1 },
1378 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b101),
1379 	  NULL, get_id_isar5_el1 },
1380 	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b001),
1381 	  NULL, get_clidr_el1 },
1382 	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b111),
1383 	  NULL, get_aidr_el1 },
1384 	{ Op0(0b11), Op1(0b011), CRn(0b0000), CRm(0b0000), Op2(0b001),
1385 	  NULL, get_ctr_el0 },
1386 };
1387 
1388 static int reg_from_user(u64 *val, const void __user *uaddr, u64 id)
1389 {
1390 	if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
1391 		return -EFAULT;
1392 	return 0;
1393 }
1394 
1395 static int reg_to_user(void __user *uaddr, const u64 *val, u64 id)
1396 {
1397 	if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
1398 		return -EFAULT;
1399 	return 0;
1400 }
1401 
1402 static int get_invariant_sys_reg(u64 id, void __user *uaddr)
1403 {
1404 	struct sys_reg_params params;
1405 	const struct sys_reg_desc *r;
1406 
1407 	if (!index_to_params(id, &params))
1408 		return -ENOENT;
1409 
1410 	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
1411 	if (!r)
1412 		return -ENOENT;
1413 
1414 	return reg_to_user(uaddr, &r->val, id);
1415 }
1416 
1417 static int set_invariant_sys_reg(u64 id, void __user *uaddr)
1418 {
1419 	struct sys_reg_params params;
1420 	const struct sys_reg_desc *r;
1421 	int err;
1422 	u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */
1423 
1424 	if (!index_to_params(id, &params))
1425 		return -ENOENT;
1426 	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
1427 	if (!r)
1428 		return -ENOENT;
1429 
1430 	err = reg_from_user(&val, uaddr, id);
1431 	if (err)
1432 		return err;
1433 
1434 	/* This is what we mean by invariant: you can't change it. */
1435 	if (r->val != val)
1436 		return -EINVAL;
1437 
1438 	return 0;
1439 }
1440 
1441 static bool is_valid_cache(u32 val)
1442 {
1443 	u32 level, ctype;
1444 
1445 	if (val >= CSSELR_MAX)
1446 		return false;
1447 
1448 	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
1449 	level = (val >> 1);
1450 	ctype = (cache_levels >> (level * 3)) & 7;
1451 
1452 	switch (ctype) {
1453 	case 0: /* No cache */
1454 		return false;
1455 	case 1: /* Instruction cache only */
1456 		return (val & 1);
1457 	case 2: /* Data cache only */
1458 	case 4: /* Unified cache */
1459 		return !(val & 1);
1460 	case 3: /* Separate instruction and data caches */
1461 		return true;
1462 	default: /* Reserved: we can't know instruction or data. */
1463 		return false;
1464 	}
1465 }
1466 
1467 static int demux_c15_get(u64 id, void __user *uaddr)
1468 {
1469 	u32 val;
1470 	u32 __user *uval = uaddr;
1471 
1472 	/* Fail if we have unknown bits set. */
1473 	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
1474 		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
1475 		return -ENOENT;
1476 
1477 	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
1478 	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
1479 		if (KVM_REG_SIZE(id) != 4)
1480 			return -ENOENT;
1481 		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
1482 			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
1483 		if (!is_valid_cache(val))
1484 			return -ENOENT;
1485 
1486 		return put_user(get_ccsidr(val), uval);
1487 	default:
1488 		return -ENOENT;
1489 	}
1490 }
1491 
1492 static int demux_c15_set(u64 id, void __user *uaddr)
1493 {
1494 	u32 val, newval;
1495 	u32 __user *uval = uaddr;
1496 
1497 	/* Fail if we have unknown bits set. */
1498 	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
1499 		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
1500 		return -ENOENT;
1501 
1502 	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
1503 	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
1504 		if (KVM_REG_SIZE(id) != 4)
1505 			return -ENOENT;
1506 		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
1507 			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
1508 		if (!is_valid_cache(val))
1509 			return -ENOENT;
1510 
1511 		if (get_user(newval, uval))
1512 			return -EFAULT;
1513 
1514 		/* This is also invariant: you can't change it. */
1515 		if (newval != get_ccsidr(val))
1516 			return -EINVAL;
1517 		return 0;
1518 	default:
1519 		return -ENOENT;
1520 	}
1521 }
1522 
1523 int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1524 {
1525 	const struct sys_reg_desc *r;
1526 	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
1527 
1528 	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1529 		return demux_c15_get(reg->id, uaddr);
1530 
1531 	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
1532 		return -ENOENT;
1533 
1534 	r = index_to_sys_reg_desc(vcpu, reg->id);
1535 	if (!r)
1536 		return get_invariant_sys_reg(reg->id, uaddr);
1537 
1538 	if (r->get_user)
1539 		return (r->get_user)(vcpu, r, reg, uaddr);
1540 
1541 	return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id);
1542 }
1543 
1544 int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1545 {
1546 	const struct sys_reg_desc *r;
1547 	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
1548 
1549 	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1550 		return demux_c15_set(reg->id, uaddr);
1551 
1552 	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
1553 		return -ENOENT;
1554 
1555 	r = index_to_sys_reg_desc(vcpu, reg->id);
1556 	if (!r)
1557 		return set_invariant_sys_reg(reg->id, uaddr);
1558 
1559 	if (r->set_user)
1560 		return (r->set_user)(vcpu, r, reg, uaddr);
1561 
1562 	return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id);
1563 }
1564 
1565 static unsigned int num_demux_regs(void)
1566 {
1567 	unsigned int i, count = 0;
1568 
1569 	for (i = 0; i < CSSELR_MAX; i++)
1570 		if (is_valid_cache(i))
1571 			count++;
1572 
1573 	return count;
1574 }
1575 
1576 static int write_demux_regids(u64 __user *uindices)
1577 {
1578 	u64 val = KVM_REG_ARM64 | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
1579 	unsigned int i;
1580 
1581 	val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
1582 	for (i = 0; i < CSSELR_MAX; i++) {
1583 		if (!is_valid_cache(i))
1584 			continue;
1585 		if (put_user(val | i, uindices))
1586 			return -EFAULT;
1587 		uindices++;
1588 	}
1589 	return 0;
1590 }
1591 
1592 static u64 sys_reg_to_index(const struct sys_reg_desc *reg)
1593 {
1594 	return (KVM_REG_ARM64 | KVM_REG_SIZE_U64 |
1595 		KVM_REG_ARM64_SYSREG |
1596 		(reg->Op0 << KVM_REG_ARM64_SYSREG_OP0_SHIFT) |
1597 		(reg->Op1 << KVM_REG_ARM64_SYSREG_OP1_SHIFT) |
1598 		(reg->CRn << KVM_REG_ARM64_SYSREG_CRN_SHIFT) |
1599 		(reg->CRm << KVM_REG_ARM64_SYSREG_CRM_SHIFT) |
1600 		(reg->Op2 << KVM_REG_ARM64_SYSREG_OP2_SHIFT));
1601 }
1602 
1603 static bool copy_reg_to_user(const struct sys_reg_desc *reg, u64 __user **uind)
1604 {
1605 	if (!*uind)
1606 		return true;
1607 
1608 	if (put_user(sys_reg_to_index(reg), *uind))
1609 		return false;
1610 
1611 	(*uind)++;
1612 	return true;
1613 }
1614 
1615 /* Assumed ordered tables, see kvm_sys_reg_table_init. */
1616 static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
1617 {
1618 	const struct sys_reg_desc *i1, *i2, *end1, *end2;
1619 	unsigned int total = 0;
1620 	size_t num;
1621 
1622 	/* We check for duplicates here, to allow arch-specific overrides. */
1623 	i1 = get_target_table(vcpu->arch.target, true, &num);
1624 	end1 = i1 + num;
1625 	i2 = sys_reg_descs;
1626 	end2 = sys_reg_descs + ARRAY_SIZE(sys_reg_descs);
1627 
1628 	BUG_ON(i1 == end1 || i2 == end2);
1629 
1630 	/* Walk carefully, as both tables may refer to the same register. */
1631 	while (i1 || i2) {
1632 		int cmp = cmp_sys_reg(i1, i2);
1633 		/* target-specific overrides generic entry. */
1634 		if (cmp <= 0) {
1635 			/* Ignore registers we trap but don't save. */
1636 			if (i1->reg) {
1637 				if (!copy_reg_to_user(i1, &uind))
1638 					return -EFAULT;
1639 				total++;
1640 			}
1641 		} else {
1642 			/* Ignore registers we trap but don't save. */
1643 			if (i2->reg) {
1644 				if (!copy_reg_to_user(i2, &uind))
1645 					return -EFAULT;
1646 				total++;
1647 			}
1648 		}
1649 
1650 		if (cmp <= 0 && ++i1 == end1)
1651 			i1 = NULL;
1652 		if (cmp >= 0 && ++i2 == end2)
1653 			i2 = NULL;
1654 	}
1655 	return total;
1656 }
1657 
1658 unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu)
1659 {
1660 	return ARRAY_SIZE(invariant_sys_regs)
1661 		+ num_demux_regs()
1662 		+ walk_sys_regs(vcpu, (u64 __user *)NULL);
1663 }
1664 
1665 int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
1666 {
1667 	unsigned int i;
1668 	int err;
1669 
1670 	/* Then give them all the invariant registers' indices. */
1671 	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++) {
1672 		if (put_user(sys_reg_to_index(&invariant_sys_regs[i]), uindices))
1673 			return -EFAULT;
1674 		uindices++;
1675 	}
1676 
1677 	err = walk_sys_regs(vcpu, uindices);
1678 	if (err < 0)
1679 		return err;
1680 	uindices += err;
1681 
1682 	return write_demux_regids(uindices);
1683 }
1684 
1685 static int check_sysreg_table(const struct sys_reg_desc *table, unsigned int n)
1686 {
1687 	unsigned int i;
1688 
1689 	for (i = 1; i < n; i++) {
1690 		if (cmp_sys_reg(&table[i-1], &table[i]) >= 0) {
1691 			kvm_err("sys_reg table %p out of order (%d)\n", table, i - 1);
1692 			return 1;
1693 		}
1694 	}
1695 
1696 	return 0;
1697 }
1698 
1699 void kvm_sys_reg_table_init(void)
1700 {
1701 	unsigned int i;
1702 	struct sys_reg_desc clidr;
1703 
1704 	/* Make sure tables are unique and in order. */
1705 	BUG_ON(check_sysreg_table(sys_reg_descs, ARRAY_SIZE(sys_reg_descs)));
1706 	BUG_ON(check_sysreg_table(cp14_regs, ARRAY_SIZE(cp14_regs)));
1707 	BUG_ON(check_sysreg_table(cp14_64_regs, ARRAY_SIZE(cp14_64_regs)));
1708 	BUG_ON(check_sysreg_table(cp15_regs, ARRAY_SIZE(cp15_regs)));
1709 	BUG_ON(check_sysreg_table(cp15_64_regs, ARRAY_SIZE(cp15_64_regs)));
1710 	BUG_ON(check_sysreg_table(invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs)));
1711 
1712 	/* We abuse the reset function to overwrite the table itself. */
1713 	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++)
1714 		invariant_sys_regs[i].reset(NULL, &invariant_sys_regs[i]);
1715 
1716 	/*
1717 	 * CLIDR format is awkward, so clean it up.  See ARM B4.1.20:
1718 	 *
1719 	 *   If software reads the Cache Type fields from Ctype1
1720 	 *   upwards, once it has seen a value of 0b000, no caches
1721 	 *   exist at further-out levels of the hierarchy. So, for
1722 	 *   example, if Ctype3 is the first Cache Type field with a
1723 	 *   value of 0b000, the values of Ctype4 to Ctype7 must be
1724 	 *   ignored.
1725 	 */
1726 	get_clidr_el1(NULL, &clidr); /* Ugly... */
1727 	cache_levels = clidr.val;
1728 	for (i = 0; i < 7; i++)
1729 		if (((cache_levels >> (i*3)) & 7) == 0)
1730 			break;
1731 	/* Clear all higher bits. */
1732 	cache_levels &= (1 << (i*3))-1;
1733 }
1734 
1735 /**
1736  * kvm_reset_sys_regs - sets system registers to reset value
1737  * @vcpu: The VCPU pointer
1738  *
1739  * This function finds the right table above and sets the registers on the
1740  * virtual CPU struct to their architecturally defined reset values.
1741  */
1742 void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
1743 {
1744 	size_t num;
1745 	const struct sys_reg_desc *table;
1746 
1747 	/* Catch someone adding a register without putting in reset entry. */
1748 	memset(&vcpu->arch.ctxt.sys_regs, 0x42, sizeof(vcpu->arch.ctxt.sys_regs));
1749 
1750 	/* Generic chip reset first (so target could override). */
1751 	reset_sys_reg_descs(vcpu, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
1752 
1753 	table = get_target_table(vcpu->arch.target, true, &num);
1754 	reset_sys_reg_descs(vcpu, table, num);
1755 
1756 	for (num = 1; num < NR_SYS_REGS; num++)
1757 		if (vcpu_sys_reg(vcpu, num) == 0x4242424242424242)
1758 			panic("Didn't reset vcpu_sys_reg(%zi)", num);
1759 }
1760