1 /*
2 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
3 * Authors: Rusty Russell <rusty@rustcorp.com.au>
4 * Christoffer Dall <c.dall@virtualopensystems.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2, as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 */
19 #include <linux/mm.h>
20 #include <linux/kvm_host.h>
21 #include <linux/uaccess.h>
22 #include <asm/kvm_arm.h>
23 #include <asm/kvm_host.h>
24 #include <asm/kvm_emulate.h>
25 #include <asm/kvm_coproc.h>
26 #include <asm/kvm_mmu.h>
27 #include <asm/cacheflush.h>
28 #include <asm/cputype.h>
29 #include <trace/events/kvm.h>
30 #include <asm/vfp.h>
31 #include "../vfp/vfpinstr.h"
32
33 #include "trace.h"
34 #include "coproc.h"
35
36
37 /******************************************************************************
38 * Co-processor emulation
39 *****************************************************************************/
40
41 /* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
42 static u32 cache_levels;
43
44 /* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
45 #define CSSELR_MAX 12
46
47 /*
48 * kvm_vcpu_arch.cp15 holds cp15 registers as an array of u32, but some
49 * of cp15 registers can be viewed either as couple of two u32 registers
50 * or one u64 register. Current u64 register encoding is that least
51 * significant u32 word is followed by most significant u32 word.
52 */
vcpu_cp15_reg64_set(struct kvm_vcpu * vcpu,const struct coproc_reg * r,u64 val)53 static inline void vcpu_cp15_reg64_set(struct kvm_vcpu *vcpu,
54 const struct coproc_reg *r,
55 u64 val)
56 {
57 vcpu->arch.cp15[r->reg] = val & 0xffffffff;
58 vcpu->arch.cp15[r->reg + 1] = val >> 32;
59 }
60
vcpu_cp15_reg64_get(struct kvm_vcpu * vcpu,const struct coproc_reg * r)61 static inline u64 vcpu_cp15_reg64_get(struct kvm_vcpu *vcpu,
62 const struct coproc_reg *r)
63 {
64 u64 val;
65
66 val = vcpu->arch.cp15[r->reg + 1];
67 val = val << 32;
68 val = val | vcpu->arch.cp15[r->reg];
69 return val;
70 }
71
kvm_handle_cp10_id(struct kvm_vcpu * vcpu,struct kvm_run * run)72 int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run)
73 {
74 kvm_inject_undefined(vcpu);
75 return 1;
76 }
77
kvm_handle_cp_0_13_access(struct kvm_vcpu * vcpu,struct kvm_run * run)78 int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
79 {
80 /*
81 * We can get here, if the host has been built without VFPv3 support,
82 * but the guest attempted a floating point operation.
83 */
84 kvm_inject_undefined(vcpu);
85 return 1;
86 }
87
kvm_handle_cp14_load_store(struct kvm_vcpu * vcpu,struct kvm_run * run)88 int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
89 {
90 kvm_inject_undefined(vcpu);
91 return 1;
92 }
93
kvm_handle_cp14_access(struct kvm_vcpu * vcpu,struct kvm_run * run)94 int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
95 {
96 kvm_inject_undefined(vcpu);
97 return 1;
98 }
99
reset_mpidr(struct kvm_vcpu * vcpu,const struct coproc_reg * r)100 static void reset_mpidr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
101 {
102 /*
103 * Compute guest MPIDR. We build a virtual cluster out of the
104 * vcpu_id, but we read the 'U' bit from the underlying
105 * hardware directly.
106 */
107 vcpu->arch.cp15[c0_MPIDR] = ((read_cpuid_mpidr() & MPIDR_SMP_BITMASK) |
108 ((vcpu->vcpu_id >> 2) << MPIDR_LEVEL_BITS) |
109 (vcpu->vcpu_id & 3));
110 }
111
112 /* TRM entries A7:4.3.31 A15:4.3.28 - RO WI */
access_actlr(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)113 static bool access_actlr(struct kvm_vcpu *vcpu,
114 const struct coproc_params *p,
115 const struct coproc_reg *r)
116 {
117 if (p->is_write)
118 return ignore_write(vcpu, p);
119
120 *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c1_ACTLR];
121 return true;
122 }
123
124 /* TRM entries A7:4.3.56, A15:4.3.60 - R/O. */
access_cbar(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)125 static bool access_cbar(struct kvm_vcpu *vcpu,
126 const struct coproc_params *p,
127 const struct coproc_reg *r)
128 {
129 if (p->is_write)
130 return write_to_read_only(vcpu, p);
131 return read_zero(vcpu, p);
132 }
133
134 /* TRM entries A7:4.3.49, A15:4.3.48 - R/O WI */
access_l2ctlr(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)135 static bool access_l2ctlr(struct kvm_vcpu *vcpu,
136 const struct coproc_params *p,
137 const struct coproc_reg *r)
138 {
139 if (p->is_write)
140 return ignore_write(vcpu, p);
141
142 *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c9_L2CTLR];
143 return true;
144 }
145
reset_l2ctlr(struct kvm_vcpu * vcpu,const struct coproc_reg * r)146 static void reset_l2ctlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
147 {
148 u32 l2ctlr, ncores;
149
150 asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r" (l2ctlr));
151 l2ctlr &= ~(3 << 24);
152 ncores = atomic_read(&vcpu->kvm->online_vcpus) - 1;
153 /* How many cores in the current cluster and the next ones */
154 ncores -= (vcpu->vcpu_id & ~3);
155 /* Cap it to the maximum number of cores in a single cluster */
156 ncores = min(ncores, 3U);
157 l2ctlr |= (ncores & 3) << 24;
158
159 vcpu->arch.cp15[c9_L2CTLR] = l2ctlr;
160 }
161
reset_actlr(struct kvm_vcpu * vcpu,const struct coproc_reg * r)162 static void reset_actlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
163 {
164 u32 actlr;
165
166 /* ACTLR contains SMP bit: make sure you create all cpus first! */
167 asm volatile("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
168 /* Make the SMP bit consistent with the guest configuration */
169 if (atomic_read(&vcpu->kvm->online_vcpus) > 1)
170 actlr |= 1U << 6;
171 else
172 actlr &= ~(1U << 6);
173
174 vcpu->arch.cp15[c1_ACTLR] = actlr;
175 }
176
177 /*
178 * TRM entries: A7:4.3.50, A15:4.3.49
179 * R/O WI (even if NSACR.NS_L2ERR, a write of 1 is ignored).
180 */
access_l2ectlr(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)181 static bool access_l2ectlr(struct kvm_vcpu *vcpu,
182 const struct coproc_params *p,
183 const struct coproc_reg *r)
184 {
185 if (p->is_write)
186 return ignore_write(vcpu, p);
187
188 *vcpu_reg(vcpu, p->Rt1) = 0;
189 return true;
190 }
191
192 /*
193 * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
194 */
access_dcsw(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)195 static bool access_dcsw(struct kvm_vcpu *vcpu,
196 const struct coproc_params *p,
197 const struct coproc_reg *r)
198 {
199 if (!p->is_write)
200 return read_from_write_only(vcpu, p);
201
202 kvm_set_way_flush(vcpu);
203 return true;
204 }
205
206 /*
207 * Generic accessor for VM registers. Only called as long as HCR_TVM
208 * is set. If the guest enables the MMU, we stop trapping the VM
209 * sys_regs and leave it in complete control of the caches.
210 *
211 * Used by the cpu-specific code.
212 */
access_vm_reg(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)213 bool access_vm_reg(struct kvm_vcpu *vcpu,
214 const struct coproc_params *p,
215 const struct coproc_reg *r)
216 {
217 bool was_enabled = vcpu_has_cache_enabled(vcpu);
218
219 BUG_ON(!p->is_write);
220
221 vcpu->arch.cp15[r->reg] = *vcpu_reg(vcpu, p->Rt1);
222 if (p->is_64bit)
223 vcpu->arch.cp15[r->reg + 1] = *vcpu_reg(vcpu, p->Rt2);
224
225 kvm_toggle_cache(vcpu, was_enabled);
226 return true;
227 }
228
229 /*
230 * We could trap ID_DFR0 and tell the guest we don't support performance
231 * monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was
232 * NAKed, so it will read the PMCR anyway.
233 *
234 * Therefore we tell the guest we have 0 counters. Unfortunately, we
235 * must always support PMCCNTR (the cycle counter): we just RAZ/WI for
236 * all PM registers, which doesn't crash the guest kernel at least.
237 */
pm_fake(struct kvm_vcpu * vcpu,const struct coproc_params * p,const struct coproc_reg * r)238 static bool pm_fake(struct kvm_vcpu *vcpu,
239 const struct coproc_params *p,
240 const struct coproc_reg *r)
241 {
242 if (p->is_write)
243 return ignore_write(vcpu, p);
244 else
245 return read_zero(vcpu, p);
246 }
247
248 #define access_pmcr pm_fake
249 #define access_pmcntenset pm_fake
250 #define access_pmcntenclr pm_fake
251 #define access_pmovsr pm_fake
252 #define access_pmselr pm_fake
253 #define access_pmceid0 pm_fake
254 #define access_pmceid1 pm_fake
255 #define access_pmccntr pm_fake
256 #define access_pmxevtyper pm_fake
257 #define access_pmxevcntr pm_fake
258 #define access_pmuserenr pm_fake
259 #define access_pmintenset pm_fake
260 #define access_pmintenclr pm_fake
261
262 /* Architected CP15 registers.
263 * CRn denotes the primary register number, but is copied to the CRm in the
264 * user space API for 64-bit register access in line with the terminology used
265 * in the ARM ARM.
266 * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 and with 64-bit
267 * registers preceding 32-bit ones.
268 */
269 static const struct coproc_reg cp15_regs[] = {
270 /* MPIDR: we use VMPIDR for guest access. */
271 { CRn( 0), CRm( 0), Op1( 0), Op2( 5), is32,
272 NULL, reset_mpidr, c0_MPIDR },
273
274 /* CSSELR: swapped by interrupt.S. */
275 { CRn( 0), CRm( 0), Op1( 2), Op2( 0), is32,
276 NULL, reset_unknown, c0_CSSELR },
277
278 /* ACTLR: trapped by HCR.TAC bit. */
279 { CRn( 1), CRm( 0), Op1( 0), Op2( 1), is32,
280 access_actlr, reset_actlr, c1_ACTLR },
281
282 /* CPACR: swapped by interrupt.S. */
283 { CRn( 1), CRm( 0), Op1( 0), Op2( 2), is32,
284 NULL, reset_val, c1_CPACR, 0x00000000 },
285
286 /* TTBR0/TTBR1/TTBCR: swapped by interrupt.S. */
287 { CRm64( 2), Op1( 0), is64, access_vm_reg, reset_unknown64, c2_TTBR0 },
288 { CRn(2), CRm( 0), Op1( 0), Op2( 0), is32,
289 access_vm_reg, reset_unknown, c2_TTBR0 },
290 { CRn(2), CRm( 0), Op1( 0), Op2( 1), is32,
291 access_vm_reg, reset_unknown, c2_TTBR1 },
292 { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32,
293 access_vm_reg, reset_val, c2_TTBCR, 0x00000000 },
294 { CRm64( 2), Op1( 1), is64, access_vm_reg, reset_unknown64, c2_TTBR1 },
295
296
297 /* DACR: swapped by interrupt.S. */
298 { CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32,
299 access_vm_reg, reset_unknown, c3_DACR },
300
301 /* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */
302 { CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32,
303 access_vm_reg, reset_unknown, c5_DFSR },
304 { CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32,
305 access_vm_reg, reset_unknown, c5_IFSR },
306 { CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32,
307 access_vm_reg, reset_unknown, c5_ADFSR },
308 { CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32,
309 access_vm_reg, reset_unknown, c5_AIFSR },
310
311 /* DFAR/IFAR: swapped by interrupt.S. */
312 { CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32,
313 access_vm_reg, reset_unknown, c6_DFAR },
314 { CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32,
315 access_vm_reg, reset_unknown, c6_IFAR },
316
317 /* PAR swapped by interrupt.S */
318 { CRm64( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR },
319
320 /*
321 * DC{C,I,CI}SW operations:
322 */
323 { CRn( 7), CRm( 6), Op1( 0), Op2( 2), is32, access_dcsw},
324 { CRn( 7), CRm(10), Op1( 0), Op2( 2), is32, access_dcsw},
325 { CRn( 7), CRm(14), Op1( 0), Op2( 2), is32, access_dcsw},
326 /*
327 * L2CTLR access (guest wants to know #CPUs).
328 */
329 { CRn( 9), CRm( 0), Op1( 1), Op2( 2), is32,
330 access_l2ctlr, reset_l2ctlr, c9_L2CTLR },
331 { CRn( 9), CRm( 0), Op1( 1), Op2( 3), is32, access_l2ectlr},
332
333 /*
334 * Dummy performance monitor implementation.
335 */
336 { CRn( 9), CRm(12), Op1( 0), Op2( 0), is32, access_pmcr},
337 { CRn( 9), CRm(12), Op1( 0), Op2( 1), is32, access_pmcntenset},
338 { CRn( 9), CRm(12), Op1( 0), Op2( 2), is32, access_pmcntenclr},
339 { CRn( 9), CRm(12), Op1( 0), Op2( 3), is32, access_pmovsr},
340 { CRn( 9), CRm(12), Op1( 0), Op2( 5), is32, access_pmselr},
341 { CRn( 9), CRm(12), Op1( 0), Op2( 6), is32, access_pmceid0},
342 { CRn( 9), CRm(12), Op1( 0), Op2( 7), is32, access_pmceid1},
343 { CRn( 9), CRm(13), Op1( 0), Op2( 0), is32, access_pmccntr},
344 { CRn( 9), CRm(13), Op1( 0), Op2( 1), is32, access_pmxevtyper},
345 { CRn( 9), CRm(13), Op1( 0), Op2( 2), is32, access_pmxevcntr},
346 { CRn( 9), CRm(14), Op1( 0), Op2( 0), is32, access_pmuserenr},
347 { CRn( 9), CRm(14), Op1( 0), Op2( 1), is32, access_pmintenset},
348 { CRn( 9), CRm(14), Op1( 0), Op2( 2), is32, access_pmintenclr},
349
350 /* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */
351 { CRn(10), CRm( 2), Op1( 0), Op2( 0), is32,
352 access_vm_reg, reset_unknown, c10_PRRR},
353 { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32,
354 access_vm_reg, reset_unknown, c10_NMRR},
355
356 /* AMAIR0/AMAIR1: swapped by interrupt.S. */
357 { CRn(10), CRm( 3), Op1( 0), Op2( 0), is32,
358 access_vm_reg, reset_unknown, c10_AMAIR0},
359 { CRn(10), CRm( 3), Op1( 0), Op2( 1), is32,
360 access_vm_reg, reset_unknown, c10_AMAIR1},
361
362 /* VBAR: swapped by interrupt.S. */
363 { CRn(12), CRm( 0), Op1( 0), Op2( 0), is32,
364 NULL, reset_val, c12_VBAR, 0x00000000 },
365
366 /* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */
367 { CRn(13), CRm( 0), Op1( 0), Op2( 1), is32,
368 access_vm_reg, reset_val, c13_CID, 0x00000000 },
369 { CRn(13), CRm( 0), Op1( 0), Op2( 2), is32,
370 NULL, reset_unknown, c13_TID_URW },
371 { CRn(13), CRm( 0), Op1( 0), Op2( 3), is32,
372 NULL, reset_unknown, c13_TID_URO },
373 { CRn(13), CRm( 0), Op1( 0), Op2( 4), is32,
374 NULL, reset_unknown, c13_TID_PRIV },
375
376 /* CNTKCTL: swapped by interrupt.S. */
377 { CRn(14), CRm( 1), Op1( 0), Op2( 0), is32,
378 NULL, reset_val, c14_CNTKCTL, 0x00000000 },
379
380 /* The Configuration Base Address Register. */
381 { CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar},
382 };
383
384 /* Target specific emulation tables */
385 static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS];
386
kvm_register_target_coproc_table(struct kvm_coproc_target_table * table)387 void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table)
388 {
389 unsigned int i;
390
391 for (i = 1; i < table->num; i++)
392 BUG_ON(cmp_reg(&table->table[i-1],
393 &table->table[i]) >= 0);
394
395 target_tables[table->target] = table;
396 }
397
398 /* Get specific register table for this target. */
get_target_table(unsigned target,size_t * num)399 static const struct coproc_reg *get_target_table(unsigned target, size_t *num)
400 {
401 struct kvm_coproc_target_table *table;
402
403 table = target_tables[target];
404 *num = table->num;
405 return table->table;
406 }
407
find_reg(const struct coproc_params * params,const struct coproc_reg table[],unsigned int num)408 static const struct coproc_reg *find_reg(const struct coproc_params *params,
409 const struct coproc_reg table[],
410 unsigned int num)
411 {
412 unsigned int i;
413
414 for (i = 0; i < num; i++) {
415 const struct coproc_reg *r = &table[i];
416
417 if (params->is_64bit != r->is_64)
418 continue;
419 if (params->CRn != r->CRn)
420 continue;
421 if (params->CRm != r->CRm)
422 continue;
423 if (params->Op1 != r->Op1)
424 continue;
425 if (params->Op2 != r->Op2)
426 continue;
427
428 return r;
429 }
430 return NULL;
431 }
432
emulate_cp15(struct kvm_vcpu * vcpu,const struct coproc_params * params)433 static int emulate_cp15(struct kvm_vcpu *vcpu,
434 const struct coproc_params *params)
435 {
436 size_t num;
437 const struct coproc_reg *table, *r;
438
439 trace_kvm_emulate_cp15_imp(params->Op1, params->Rt1, params->CRn,
440 params->CRm, params->Op2, params->is_write);
441
442 table = get_target_table(vcpu->arch.target, &num);
443
444 /* Search target-specific then generic table. */
445 r = find_reg(params, table, num);
446 if (!r)
447 r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs));
448
449 if (likely(r)) {
450 /* If we don't have an accessor, we should never get here! */
451 BUG_ON(!r->access);
452
453 if (likely(r->access(vcpu, params, r))) {
454 /* Skip instruction, since it was emulated */
455 kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
456 return 1;
457 }
458 /* If access function fails, it should complain. */
459 } else {
460 kvm_err("Unsupported guest CP15 access at: %08lx\n",
461 *vcpu_pc(vcpu));
462 print_cp_instr(params);
463 }
464 kvm_inject_undefined(vcpu);
465 return 1;
466 }
467
468 /**
469 * kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access
470 * @vcpu: The VCPU pointer
471 * @run: The kvm_run struct
472 */
kvm_handle_cp15_64(struct kvm_vcpu * vcpu,struct kvm_run * run)473 int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
474 {
475 struct coproc_params params;
476
477 params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
478 params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf;
479 params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0);
480 params.is_64bit = true;
481
482 params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 16) & 0xf;
483 params.Op2 = 0;
484 params.Rt2 = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
485 params.CRm = 0;
486
487 return emulate_cp15(vcpu, ¶ms);
488 }
489
reset_coproc_regs(struct kvm_vcpu * vcpu,const struct coproc_reg * table,size_t num)490 static void reset_coproc_regs(struct kvm_vcpu *vcpu,
491 const struct coproc_reg *table, size_t num)
492 {
493 unsigned long i;
494
495 for (i = 0; i < num; i++)
496 if (table[i].reset)
497 table[i].reset(vcpu, &table[i]);
498 }
499
500 /**
501 * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
502 * @vcpu: The VCPU pointer
503 * @run: The kvm_run struct
504 */
kvm_handle_cp15_32(struct kvm_vcpu * vcpu,struct kvm_run * run)505 int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
506 {
507 struct coproc_params params;
508
509 params.CRm = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
510 params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf;
511 params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0);
512 params.is_64bit = false;
513
514 params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
515 params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 14) & 0x7;
516 params.Op2 = (kvm_vcpu_get_hsr(vcpu) >> 17) & 0x7;
517 params.Rt2 = 0;
518
519 return emulate_cp15(vcpu, ¶ms);
520 }
521
522 /******************************************************************************
523 * Userspace API
524 *****************************************************************************/
525
index_to_params(u64 id,struct coproc_params * params)526 static bool index_to_params(u64 id, struct coproc_params *params)
527 {
528 switch (id & KVM_REG_SIZE_MASK) {
529 case KVM_REG_SIZE_U32:
530 /* Any unused index bits means it's not valid. */
531 if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
532 | KVM_REG_ARM_COPROC_MASK
533 | KVM_REG_ARM_32_CRN_MASK
534 | KVM_REG_ARM_CRM_MASK
535 | KVM_REG_ARM_OPC1_MASK
536 | KVM_REG_ARM_32_OPC2_MASK))
537 return false;
538
539 params->is_64bit = false;
540 params->CRn = ((id & KVM_REG_ARM_32_CRN_MASK)
541 >> KVM_REG_ARM_32_CRN_SHIFT);
542 params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
543 >> KVM_REG_ARM_CRM_SHIFT);
544 params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
545 >> KVM_REG_ARM_OPC1_SHIFT);
546 params->Op2 = ((id & KVM_REG_ARM_32_OPC2_MASK)
547 >> KVM_REG_ARM_32_OPC2_SHIFT);
548 return true;
549 case KVM_REG_SIZE_U64:
550 /* Any unused index bits means it's not valid. */
551 if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
552 | KVM_REG_ARM_COPROC_MASK
553 | KVM_REG_ARM_CRM_MASK
554 | KVM_REG_ARM_OPC1_MASK))
555 return false;
556 params->is_64bit = true;
557 /* CRm to CRn: see cp15_to_index for details */
558 params->CRn = ((id & KVM_REG_ARM_CRM_MASK)
559 >> KVM_REG_ARM_CRM_SHIFT);
560 params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
561 >> KVM_REG_ARM_OPC1_SHIFT);
562 params->Op2 = 0;
563 params->CRm = 0;
564 return true;
565 default:
566 return false;
567 }
568 }
569
570 /* Decode an index value, and find the cp15 coproc_reg entry. */
index_to_coproc_reg(struct kvm_vcpu * vcpu,u64 id)571 static const struct coproc_reg *index_to_coproc_reg(struct kvm_vcpu *vcpu,
572 u64 id)
573 {
574 size_t num;
575 const struct coproc_reg *table, *r;
576 struct coproc_params params;
577
578 /* We only do cp15 for now. */
579 if ((id & KVM_REG_ARM_COPROC_MASK) >> KVM_REG_ARM_COPROC_SHIFT != 15)
580 return NULL;
581
582 if (!index_to_params(id, ¶ms))
583 return NULL;
584
585 table = get_target_table(vcpu->arch.target, &num);
586 r = find_reg(¶ms, table, num);
587 if (!r)
588 r = find_reg(¶ms, cp15_regs, ARRAY_SIZE(cp15_regs));
589
590 /* Not saved in the cp15 array? */
591 if (r && !r->reg)
592 r = NULL;
593
594 return r;
595 }
596
597 /*
598 * These are the invariant cp15 registers: we let the guest see the host
599 * versions of these, so they're part of the guest state.
600 *
601 * A future CPU may provide a mechanism to present different values to
602 * the guest, or a future kvm may trap them.
603 */
604 /* Unfortunately, there's no register-argument for mrc, so generate. */
605 #define FUNCTION_FOR32(crn, crm, op1, op2, name) \
606 static void get_##name(struct kvm_vcpu *v, \
607 const struct coproc_reg *r) \
608 { \
609 u32 val; \
610 \
611 asm volatile("mrc p15, " __stringify(op1) \
612 ", %0, c" __stringify(crn) \
613 ", c" __stringify(crm) \
614 ", " __stringify(op2) "\n" : "=r" (val)); \
615 ((struct coproc_reg *)r)->val = val; \
616 }
617
618 FUNCTION_FOR32(0, 0, 0, 0, MIDR)
619 FUNCTION_FOR32(0, 0, 0, 1, CTR)
620 FUNCTION_FOR32(0, 0, 0, 2, TCMTR)
621 FUNCTION_FOR32(0, 0, 0, 3, TLBTR)
622 FUNCTION_FOR32(0, 0, 0, 6, REVIDR)
623 FUNCTION_FOR32(0, 1, 0, 0, ID_PFR0)
624 FUNCTION_FOR32(0, 1, 0, 1, ID_PFR1)
625 FUNCTION_FOR32(0, 1, 0, 2, ID_DFR0)
626 FUNCTION_FOR32(0, 1, 0, 3, ID_AFR0)
627 FUNCTION_FOR32(0, 1, 0, 4, ID_MMFR0)
628 FUNCTION_FOR32(0, 1, 0, 5, ID_MMFR1)
629 FUNCTION_FOR32(0, 1, 0, 6, ID_MMFR2)
630 FUNCTION_FOR32(0, 1, 0, 7, ID_MMFR3)
631 FUNCTION_FOR32(0, 2, 0, 0, ID_ISAR0)
632 FUNCTION_FOR32(0, 2, 0, 1, ID_ISAR1)
633 FUNCTION_FOR32(0, 2, 0, 2, ID_ISAR2)
634 FUNCTION_FOR32(0, 2, 0, 3, ID_ISAR3)
635 FUNCTION_FOR32(0, 2, 0, 4, ID_ISAR4)
636 FUNCTION_FOR32(0, 2, 0, 5, ID_ISAR5)
637 FUNCTION_FOR32(0, 0, 1, 1, CLIDR)
638 FUNCTION_FOR32(0, 0, 1, 7, AIDR)
639
640 /* ->val is filled in by kvm_invariant_coproc_table_init() */
641 static struct coproc_reg invariant_cp15[] = {
642 { CRn( 0), CRm( 0), Op1( 0), Op2( 0), is32, NULL, get_MIDR },
643 { CRn( 0), CRm( 0), Op1( 0), Op2( 1), is32, NULL, get_CTR },
644 { CRn( 0), CRm( 0), Op1( 0), Op2( 2), is32, NULL, get_TCMTR },
645 { CRn( 0), CRm( 0), Op1( 0), Op2( 3), is32, NULL, get_TLBTR },
646 { CRn( 0), CRm( 0), Op1( 0), Op2( 6), is32, NULL, get_REVIDR },
647
648 { CRn( 0), CRm( 1), Op1( 0), Op2( 0), is32, NULL, get_ID_PFR0 },
649 { CRn( 0), CRm( 1), Op1( 0), Op2( 1), is32, NULL, get_ID_PFR1 },
650 { CRn( 0), CRm( 1), Op1( 0), Op2( 2), is32, NULL, get_ID_DFR0 },
651 { CRn( 0), CRm( 1), Op1( 0), Op2( 3), is32, NULL, get_ID_AFR0 },
652 { CRn( 0), CRm( 1), Op1( 0), Op2( 4), is32, NULL, get_ID_MMFR0 },
653 { CRn( 0), CRm( 1), Op1( 0), Op2( 5), is32, NULL, get_ID_MMFR1 },
654 { CRn( 0), CRm( 1), Op1( 0), Op2( 6), is32, NULL, get_ID_MMFR2 },
655 { CRn( 0), CRm( 1), Op1( 0), Op2( 7), is32, NULL, get_ID_MMFR3 },
656
657 { CRn( 0), CRm( 2), Op1( 0), Op2( 0), is32, NULL, get_ID_ISAR0 },
658 { CRn( 0), CRm( 2), Op1( 0), Op2( 1), is32, NULL, get_ID_ISAR1 },
659 { CRn( 0), CRm( 2), Op1( 0), Op2( 2), is32, NULL, get_ID_ISAR2 },
660 { CRn( 0), CRm( 2), Op1( 0), Op2( 3), is32, NULL, get_ID_ISAR3 },
661 { CRn( 0), CRm( 2), Op1( 0), Op2( 4), is32, NULL, get_ID_ISAR4 },
662 { CRn( 0), CRm( 2), Op1( 0), Op2( 5), is32, NULL, get_ID_ISAR5 },
663
664 { CRn( 0), CRm( 0), Op1( 1), Op2( 1), is32, NULL, get_CLIDR },
665 { CRn( 0), CRm( 0), Op1( 1), Op2( 7), is32, NULL, get_AIDR },
666 };
667
668 /*
669 * Reads a register value from a userspace address to a kernel
670 * variable. Make sure that register size matches sizeof(*__val).
671 */
reg_from_user(void * val,const void __user * uaddr,u64 id)672 static int reg_from_user(void *val, const void __user *uaddr, u64 id)
673 {
674 if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
675 return -EFAULT;
676 return 0;
677 }
678
679 /*
680 * Writes a register value to a userspace address from a kernel variable.
681 * Make sure that register size matches sizeof(*__val).
682 */
reg_to_user(void __user * uaddr,const void * val,u64 id)683 static int reg_to_user(void __user *uaddr, const void *val, u64 id)
684 {
685 if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
686 return -EFAULT;
687 return 0;
688 }
689
get_invariant_cp15(u64 id,void __user * uaddr)690 static int get_invariant_cp15(u64 id, void __user *uaddr)
691 {
692 struct coproc_params params;
693 const struct coproc_reg *r;
694 int ret;
695
696 if (!index_to_params(id, ¶ms))
697 return -ENOENT;
698
699 r = find_reg(¶ms, invariant_cp15, ARRAY_SIZE(invariant_cp15));
700 if (!r)
701 return -ENOENT;
702
703 ret = -ENOENT;
704 if (KVM_REG_SIZE(id) == 4) {
705 u32 val = r->val;
706
707 ret = reg_to_user(uaddr, &val, id);
708 } else if (KVM_REG_SIZE(id) == 8) {
709 ret = reg_to_user(uaddr, &r->val, id);
710 }
711 return ret;
712 }
713
set_invariant_cp15(u64 id,void __user * uaddr)714 static int set_invariant_cp15(u64 id, void __user *uaddr)
715 {
716 struct coproc_params params;
717 const struct coproc_reg *r;
718 int err;
719 u64 val;
720
721 if (!index_to_params(id, ¶ms))
722 return -ENOENT;
723 r = find_reg(¶ms, invariant_cp15, ARRAY_SIZE(invariant_cp15));
724 if (!r)
725 return -ENOENT;
726
727 err = -ENOENT;
728 if (KVM_REG_SIZE(id) == 4) {
729 u32 val32;
730
731 err = reg_from_user(&val32, uaddr, id);
732 if (!err)
733 val = val32;
734 } else if (KVM_REG_SIZE(id) == 8) {
735 err = reg_from_user(&val, uaddr, id);
736 }
737 if (err)
738 return err;
739
740 /* This is what we mean by invariant: you can't change it. */
741 if (r->val != val)
742 return -EINVAL;
743
744 return 0;
745 }
746
is_valid_cache(u32 val)747 static bool is_valid_cache(u32 val)
748 {
749 u32 level, ctype;
750
751 if (val >= CSSELR_MAX)
752 return false;
753
754 /* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
755 level = (val >> 1);
756 ctype = (cache_levels >> (level * 3)) & 7;
757
758 switch (ctype) {
759 case 0: /* No cache */
760 return false;
761 case 1: /* Instruction cache only */
762 return (val & 1);
763 case 2: /* Data cache only */
764 case 4: /* Unified cache */
765 return !(val & 1);
766 case 3: /* Separate instruction and data caches */
767 return true;
768 default: /* Reserved: we can't know instruction or data. */
769 return false;
770 }
771 }
772
773 /* Which cache CCSIDR represents depends on CSSELR value. */
get_ccsidr(u32 csselr)774 static u32 get_ccsidr(u32 csselr)
775 {
776 u32 ccsidr;
777
778 /* Make sure noone else changes CSSELR during this! */
779 local_irq_disable();
780 /* Put value into CSSELR */
781 asm volatile("mcr p15, 2, %0, c0, c0, 0" : : "r" (csselr));
782 isb();
783 /* Read result out of CCSIDR */
784 asm volatile("mrc p15, 1, %0, c0, c0, 0" : "=r" (ccsidr));
785 local_irq_enable();
786
787 return ccsidr;
788 }
789
demux_c15_get(u64 id,void __user * uaddr)790 static int demux_c15_get(u64 id, void __user *uaddr)
791 {
792 u32 val;
793 u32 __user *uval = uaddr;
794
795 /* Fail if we have unknown bits set. */
796 if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
797 | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
798 return -ENOENT;
799
800 switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
801 case KVM_REG_ARM_DEMUX_ID_CCSIDR:
802 if (KVM_REG_SIZE(id) != 4)
803 return -ENOENT;
804 val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
805 >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
806 if (!is_valid_cache(val))
807 return -ENOENT;
808
809 return put_user(get_ccsidr(val), uval);
810 default:
811 return -ENOENT;
812 }
813 }
814
demux_c15_set(u64 id,void __user * uaddr)815 static int demux_c15_set(u64 id, void __user *uaddr)
816 {
817 u32 val, newval;
818 u32 __user *uval = uaddr;
819
820 /* Fail if we have unknown bits set. */
821 if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
822 | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
823 return -ENOENT;
824
825 switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
826 case KVM_REG_ARM_DEMUX_ID_CCSIDR:
827 if (KVM_REG_SIZE(id) != 4)
828 return -ENOENT;
829 val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
830 >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
831 if (!is_valid_cache(val))
832 return -ENOENT;
833
834 if (get_user(newval, uval))
835 return -EFAULT;
836
837 /* This is also invariant: you can't change it. */
838 if (newval != get_ccsidr(val))
839 return -EINVAL;
840 return 0;
841 default:
842 return -ENOENT;
843 }
844 }
845
846 #ifdef CONFIG_VFPv3
847 static const int vfp_sysregs[] = { KVM_REG_ARM_VFP_FPEXC,
848 KVM_REG_ARM_VFP_FPSCR,
849 KVM_REG_ARM_VFP_FPINST,
850 KVM_REG_ARM_VFP_FPINST2,
851 KVM_REG_ARM_VFP_MVFR0,
852 KVM_REG_ARM_VFP_MVFR1,
853 KVM_REG_ARM_VFP_FPSID };
854
num_fp_regs(void)855 static unsigned int num_fp_regs(void)
856 {
857 if (((fmrx(MVFR0) & MVFR0_A_SIMD_MASK) >> MVFR0_A_SIMD_BIT) == 2)
858 return 32;
859 else
860 return 16;
861 }
862
num_vfp_regs(void)863 static unsigned int num_vfp_regs(void)
864 {
865 /* Normal FP regs + control regs. */
866 return num_fp_regs() + ARRAY_SIZE(vfp_sysregs);
867 }
868
copy_vfp_regids(u64 __user * uindices)869 static int copy_vfp_regids(u64 __user *uindices)
870 {
871 unsigned int i;
872 const u64 u32reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP;
873 const u64 u64reg = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
874
875 for (i = 0; i < num_fp_regs(); i++) {
876 if (put_user((u64reg | KVM_REG_ARM_VFP_BASE_REG) + i,
877 uindices))
878 return -EFAULT;
879 uindices++;
880 }
881
882 for (i = 0; i < ARRAY_SIZE(vfp_sysregs); i++) {
883 if (put_user(u32reg | vfp_sysregs[i], uindices))
884 return -EFAULT;
885 uindices++;
886 }
887
888 return num_vfp_regs();
889 }
890
vfp_get_reg(const struct kvm_vcpu * vcpu,u64 id,void __user * uaddr)891 static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)
892 {
893 u32 vfpid = (id & KVM_REG_ARM_VFP_MASK);
894 u32 val;
895
896 /* Fail if we have unknown bits set. */
897 if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
898 | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
899 return -ENOENT;
900
901 if (vfpid < num_fp_regs()) {
902 if (KVM_REG_SIZE(id) != 8)
903 return -ENOENT;
904 return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpregs[vfpid],
905 id);
906 }
907
908 /* FP control registers are all 32 bit. */
909 if (KVM_REG_SIZE(id) != 4)
910 return -ENOENT;
911
912 switch (vfpid) {
913 case KVM_REG_ARM_VFP_FPEXC:
914 return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpexc, id);
915 case KVM_REG_ARM_VFP_FPSCR:
916 return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpscr, id);
917 case KVM_REG_ARM_VFP_FPINST:
918 return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst, id);
919 case KVM_REG_ARM_VFP_FPINST2:
920 return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst2, id);
921 case KVM_REG_ARM_VFP_MVFR0:
922 val = fmrx(MVFR0);
923 return reg_to_user(uaddr, &val, id);
924 case KVM_REG_ARM_VFP_MVFR1:
925 val = fmrx(MVFR1);
926 return reg_to_user(uaddr, &val, id);
927 case KVM_REG_ARM_VFP_FPSID:
928 val = fmrx(FPSID);
929 return reg_to_user(uaddr, &val, id);
930 default:
931 return -ENOENT;
932 }
933 }
934
vfp_set_reg(struct kvm_vcpu * vcpu,u64 id,const void __user * uaddr)935 static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)
936 {
937 u32 vfpid = (id & KVM_REG_ARM_VFP_MASK);
938 u32 val;
939
940 /* Fail if we have unknown bits set. */
941 if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
942 | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
943 return -ENOENT;
944
945 if (vfpid < num_fp_regs()) {
946 if (KVM_REG_SIZE(id) != 8)
947 return -ENOENT;
948 return reg_from_user(&vcpu->arch.vfp_guest.fpregs[vfpid],
949 uaddr, id);
950 }
951
952 /* FP control registers are all 32 bit. */
953 if (KVM_REG_SIZE(id) != 4)
954 return -ENOENT;
955
956 switch (vfpid) {
957 case KVM_REG_ARM_VFP_FPEXC:
958 return reg_from_user(&vcpu->arch.vfp_guest.fpexc, uaddr, id);
959 case KVM_REG_ARM_VFP_FPSCR:
960 return reg_from_user(&vcpu->arch.vfp_guest.fpscr, uaddr, id);
961 case KVM_REG_ARM_VFP_FPINST:
962 return reg_from_user(&vcpu->arch.vfp_guest.fpinst, uaddr, id);
963 case KVM_REG_ARM_VFP_FPINST2:
964 return reg_from_user(&vcpu->arch.vfp_guest.fpinst2, uaddr, id);
965 /* These are invariant. */
966 case KVM_REG_ARM_VFP_MVFR0:
967 if (reg_from_user(&val, uaddr, id))
968 return -EFAULT;
969 if (val != fmrx(MVFR0))
970 return -EINVAL;
971 return 0;
972 case KVM_REG_ARM_VFP_MVFR1:
973 if (reg_from_user(&val, uaddr, id))
974 return -EFAULT;
975 if (val != fmrx(MVFR1))
976 return -EINVAL;
977 return 0;
978 case KVM_REG_ARM_VFP_FPSID:
979 if (reg_from_user(&val, uaddr, id))
980 return -EFAULT;
981 if (val != fmrx(FPSID))
982 return -EINVAL;
983 return 0;
984 default:
985 return -ENOENT;
986 }
987 }
988 #else /* !CONFIG_VFPv3 */
num_vfp_regs(void)989 static unsigned int num_vfp_regs(void)
990 {
991 return 0;
992 }
993
copy_vfp_regids(u64 __user * uindices)994 static int copy_vfp_regids(u64 __user *uindices)
995 {
996 return 0;
997 }
998
vfp_get_reg(const struct kvm_vcpu * vcpu,u64 id,void __user * uaddr)999 static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)
1000 {
1001 return -ENOENT;
1002 }
1003
vfp_set_reg(struct kvm_vcpu * vcpu,u64 id,const void __user * uaddr)1004 static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)
1005 {
1006 return -ENOENT;
1007 }
1008 #endif /* !CONFIG_VFPv3 */
1009
kvm_arm_coproc_get_reg(struct kvm_vcpu * vcpu,const struct kvm_one_reg * reg)1010 int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1011 {
1012 const struct coproc_reg *r;
1013 void __user *uaddr = (void __user *)(long)reg->addr;
1014 int ret;
1015
1016 if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1017 return demux_c15_get(reg->id, uaddr);
1018
1019 if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_VFP)
1020 return vfp_get_reg(vcpu, reg->id, uaddr);
1021
1022 r = index_to_coproc_reg(vcpu, reg->id);
1023 if (!r)
1024 return get_invariant_cp15(reg->id, uaddr);
1025
1026 ret = -ENOENT;
1027 if (KVM_REG_SIZE(reg->id) == 8) {
1028 u64 val;
1029
1030 val = vcpu_cp15_reg64_get(vcpu, r);
1031 ret = reg_to_user(uaddr, &val, reg->id);
1032 } else if (KVM_REG_SIZE(reg->id) == 4) {
1033 ret = reg_to_user(uaddr, &vcpu->arch.cp15[r->reg], reg->id);
1034 }
1035
1036 return ret;
1037 }
1038
kvm_arm_coproc_set_reg(struct kvm_vcpu * vcpu,const struct kvm_one_reg * reg)1039 int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1040 {
1041 const struct coproc_reg *r;
1042 void __user *uaddr = (void __user *)(long)reg->addr;
1043 int ret;
1044
1045 if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1046 return demux_c15_set(reg->id, uaddr);
1047
1048 if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_VFP)
1049 return vfp_set_reg(vcpu, reg->id, uaddr);
1050
1051 r = index_to_coproc_reg(vcpu, reg->id);
1052 if (!r)
1053 return set_invariant_cp15(reg->id, uaddr);
1054
1055 ret = -ENOENT;
1056 if (KVM_REG_SIZE(reg->id) == 8) {
1057 u64 val;
1058
1059 ret = reg_from_user(&val, uaddr, reg->id);
1060 if (!ret)
1061 vcpu_cp15_reg64_set(vcpu, r, val);
1062 } else if (KVM_REG_SIZE(reg->id) == 4) {
1063 ret = reg_from_user(&vcpu->arch.cp15[r->reg], uaddr, reg->id);
1064 }
1065
1066 return ret;
1067 }
1068
num_demux_regs(void)1069 static unsigned int num_demux_regs(void)
1070 {
1071 unsigned int i, count = 0;
1072
1073 for (i = 0; i < CSSELR_MAX; i++)
1074 if (is_valid_cache(i))
1075 count++;
1076
1077 return count;
1078 }
1079
write_demux_regids(u64 __user * uindices)1080 static int write_demux_regids(u64 __user *uindices)
1081 {
1082 u64 val = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
1083 unsigned int i;
1084
1085 val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
1086 for (i = 0; i < CSSELR_MAX; i++) {
1087 if (!is_valid_cache(i))
1088 continue;
1089 if (put_user(val | i, uindices))
1090 return -EFAULT;
1091 uindices++;
1092 }
1093 return 0;
1094 }
1095
cp15_to_index(const struct coproc_reg * reg)1096 static u64 cp15_to_index(const struct coproc_reg *reg)
1097 {
1098 u64 val = KVM_REG_ARM | (15 << KVM_REG_ARM_COPROC_SHIFT);
1099 if (reg->is_64) {
1100 val |= KVM_REG_SIZE_U64;
1101 val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
1102 /*
1103 * CRn always denotes the primary coproc. reg. nr. for the
1104 * in-kernel representation, but the user space API uses the
1105 * CRm for the encoding, because it is modelled after the
1106 * MRRC/MCRR instructions: see the ARM ARM rev. c page
1107 * B3-1445
1108 */
1109 val |= (reg->CRn << KVM_REG_ARM_CRM_SHIFT);
1110 } else {
1111 val |= KVM_REG_SIZE_U32;
1112 val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
1113 val |= (reg->Op2 << KVM_REG_ARM_32_OPC2_SHIFT);
1114 val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
1115 val |= (reg->CRn << KVM_REG_ARM_32_CRN_SHIFT);
1116 }
1117 return val;
1118 }
1119
copy_reg_to_user(const struct coproc_reg * reg,u64 __user ** uind)1120 static bool copy_reg_to_user(const struct coproc_reg *reg, u64 __user **uind)
1121 {
1122 if (!*uind)
1123 return true;
1124
1125 if (put_user(cp15_to_index(reg), *uind))
1126 return false;
1127
1128 (*uind)++;
1129 return true;
1130 }
1131
1132 /* Assumed ordered tables, see kvm_coproc_table_init. */
walk_cp15(struct kvm_vcpu * vcpu,u64 __user * uind)1133 static int walk_cp15(struct kvm_vcpu *vcpu, u64 __user *uind)
1134 {
1135 const struct coproc_reg *i1, *i2, *end1, *end2;
1136 unsigned int total = 0;
1137 size_t num;
1138
1139 /* We check for duplicates here, to allow arch-specific overrides. */
1140 i1 = get_target_table(vcpu->arch.target, &num);
1141 end1 = i1 + num;
1142 i2 = cp15_regs;
1143 end2 = cp15_regs + ARRAY_SIZE(cp15_regs);
1144
1145 BUG_ON(i1 == end1 || i2 == end2);
1146
1147 /* Walk carefully, as both tables may refer to the same register. */
1148 while (i1 || i2) {
1149 int cmp = cmp_reg(i1, i2);
1150 /* target-specific overrides generic entry. */
1151 if (cmp <= 0) {
1152 /* Ignore registers we trap but don't save. */
1153 if (i1->reg) {
1154 if (!copy_reg_to_user(i1, &uind))
1155 return -EFAULT;
1156 total++;
1157 }
1158 } else {
1159 /* Ignore registers we trap but don't save. */
1160 if (i2->reg) {
1161 if (!copy_reg_to_user(i2, &uind))
1162 return -EFAULT;
1163 total++;
1164 }
1165 }
1166
1167 if (cmp <= 0 && ++i1 == end1)
1168 i1 = NULL;
1169 if (cmp >= 0 && ++i2 == end2)
1170 i2 = NULL;
1171 }
1172 return total;
1173 }
1174
kvm_arm_num_coproc_regs(struct kvm_vcpu * vcpu)1175 unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
1176 {
1177 return ARRAY_SIZE(invariant_cp15)
1178 + num_demux_regs()
1179 + num_vfp_regs()
1180 + walk_cp15(vcpu, (u64 __user *)NULL);
1181 }
1182
kvm_arm_copy_coproc_indices(struct kvm_vcpu * vcpu,u64 __user * uindices)1183 int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
1184 {
1185 unsigned int i;
1186 int err;
1187
1188 /* Then give them all the invariant registers' indices. */
1189 for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++) {
1190 if (put_user(cp15_to_index(&invariant_cp15[i]), uindices))
1191 return -EFAULT;
1192 uindices++;
1193 }
1194
1195 err = walk_cp15(vcpu, uindices);
1196 if (err < 0)
1197 return err;
1198 uindices += err;
1199
1200 err = copy_vfp_regids(uindices);
1201 if (err < 0)
1202 return err;
1203 uindices += err;
1204
1205 return write_demux_regids(uindices);
1206 }
1207
kvm_coproc_table_init(void)1208 void kvm_coproc_table_init(void)
1209 {
1210 unsigned int i;
1211
1212 /* Make sure tables are unique and in order. */
1213 for (i = 1; i < ARRAY_SIZE(cp15_regs); i++)
1214 BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0);
1215
1216 /* We abuse the reset function to overwrite the table itself. */
1217 for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++)
1218 invariant_cp15[i].reset(NULL, &invariant_cp15[i]);
1219
1220 /*
1221 * CLIDR format is awkward, so clean it up. See ARM B4.1.20:
1222 *
1223 * If software reads the Cache Type fields from Ctype1
1224 * upwards, once it has seen a value of 0b000, no caches
1225 * exist at further-out levels of the hierarchy. So, for
1226 * example, if Ctype3 is the first Cache Type field with a
1227 * value of 0b000, the values of Ctype4 to Ctype7 must be
1228 * ignored.
1229 */
1230 asm volatile("mrc p15, 1, %0, c0, c0, 1" : "=r" (cache_levels));
1231 for (i = 0; i < 7; i++)
1232 if (((cache_levels >> (i*3)) & 7) == 0)
1233 break;
1234 /* Clear all higher bits. */
1235 cache_levels &= (1 << (i*3))-1;
1236 }
1237
1238 /**
1239 * kvm_reset_coprocs - sets cp15 registers to reset value
1240 * @vcpu: The VCPU pointer
1241 *
1242 * This function finds the right table above and sets the registers on the
1243 * virtual CPU struct to their architecturally defined reset values.
1244 */
kvm_reset_coprocs(struct kvm_vcpu * vcpu)1245 void kvm_reset_coprocs(struct kvm_vcpu *vcpu)
1246 {
1247 size_t num;
1248 const struct coproc_reg *table;
1249
1250 /* Catch someone adding a register without putting in reset entry. */
1251 memset(vcpu->arch.cp15, 0x42, sizeof(vcpu->arch.cp15));
1252
1253 /* Generic chip reset first (so target could override). */
1254 reset_coproc_regs(vcpu, cp15_regs, ARRAY_SIZE(cp15_regs));
1255
1256 table = get_target_table(vcpu->arch.target, &num);
1257 reset_coproc_regs(vcpu, table, num);
1258
1259 for (num = 1; num < NR_CP15_REGS; num++)
1260 if (vcpu->arch.cp15[num] == 0x42424242)
1261 panic("Didn't reset vcpu->arch.cp15[%zi]", num);
1262 }
1263