summaryrefslogtreecommitdiff
path: root/arch/mips/kvm/kvm_trap_emul.c
blob: 466aeef044bd18c777ba6adff2dde1f4366b3fb3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
/*
* This file is subject to the terms and conditions of the GNU General Public
* License.  See the file "COPYING" in the main directory of this archive
* for more details.
*
* KVM/MIPS: Deliver/Emulate exceptions to the guest kernel
*
* Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
* Authors: Sanjay Lal <sanjayl@kymasys.com>
*/

#include <linux/errno.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/vmalloc.h>

#include <linux/kvm_host.h>

#include "kvm_mips_opcode.h"
#include "kvm_mips_int.h"

static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
{
	gpa_t gpa;
	uint32_t kseg = KSEGX(gva);

	if ((kseg == CKSEG0) || (kseg == CKSEG1))
		gpa = CPHYSADDR(gva);
	else {
		printk("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
		kvm_mips_dump_host_tlbs();
		gpa = KVM_INVALID_ADDR;
	}

#ifdef DEBUG
	kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
#endif

	return gpa;
}


static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
		er = kvm_mips_emulate_fpu_exc(cause, opc, run, vcpu);
	} else
		er = kvm_mips_emulate_inst(cause, opc, run, vcpu);

	switch (er) {
	case EMULATE_DONE:
		ret = RESUME_GUEST;
		break;

	case EMULATE_FAIL:
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
		break;

	case EMULATE_WAIT:
		run->exit_reason = KVM_EXIT_INTR;
		ret = RESUME_HOST;
		break;

	default:
		BUG();
	}
	return ret;
}

static int kvm_trap_emul_handle_tlb_mod(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
	    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
#ifdef DEBUG
		kvm_debug
		    ("USER/KSEG23 ADDR TLB MOD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
#endif
		er = kvm_mips_handle_tlbmod(cause, opc, run, vcpu);

		if (er == EMULATE_DONE)
			ret = RESUME_GUEST;
		else {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
		/* XXXKYMA: The guest kernel does not expect to get this fault when we are not
		 * using HIGHMEM. Need to address this in a HIGHMEM kernel
		 */
		printk
		    ("TLB MOD fault not handled, cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		kvm_mips_dump_host_tlbs();
		kvm_arch_vcpu_dump_regs(vcpu);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	} else {
		printk
		    ("Illegal TLB Mod fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		kvm_mips_dump_host_tlbs();
		kvm_arch_vcpu_dump_regs(vcpu);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
	    && KVM_GUEST_KERNEL_MODE(vcpu)) {
		if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
		   || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
#ifdef DEBUG
		kvm_debug
		    ("USER ADDR TLB LD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
#endif
		er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
		if (er == EMULATE_DONE)
			ret = RESUME_GUEST;
		else {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
		/* All KSEG0 faults are handled by KVM, as the guest kernel does not
		 * expect to ever get them
		 */
		if (kvm_mips_handle_kseg0_tlb_fault
		    (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else {
		kvm_err
		    ("Illegal TLB LD fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		kvm_mips_dump_host_tlbs();
		kvm_arch_vcpu_dump_regs(vcpu);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
	    && KVM_GUEST_KERNEL_MODE(vcpu)) {
		if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
		   || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
#ifdef DEBUG
		kvm_debug("USER ADDR TLB ST fault: PC: %#lx, BadVaddr: %#lx\n",
			  vcpu->arch.pc, badvaddr);
#endif

		/* User Address (UA) fault, this could happen if
		 * (1) TLB entry not present/valid in both Guest and shadow host TLBs, in this
		 *     case we pass on the fault to the guest kernel and let it handle it.
		 * (2) TLB entry is present in the Guest TLB but not in the shadow, in this
		 *     case we inject the TLB from the Guest TLB into the shadow host TLB
		 */

		er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
		if (er == EMULATE_DONE)
			ret = RESUME_GUEST;
		else {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
		if (kvm_mips_handle_kseg0_tlb_fault
		    (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		}
	} else {
		printk
		    ("Illegal TLB ST fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		kvm_mips_dump_host_tlbs();
		kvm_arch_vcpu_dump_regs(vcpu);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_addr_err_st(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (KVM_GUEST_KERNEL_MODE(vcpu)
	    && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
#ifdef DEBUG
		kvm_debug("Emulate Store to MMIO space\n");
#endif
		er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
		if (er == EMULATE_FAIL) {
			printk("Emulate Store to MMIO space failed\n");
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		} else {
			run->exit_reason = KVM_EXIT_MMIO;
			ret = RESUME_HOST;
		}
	} else {
		printk
		    ("Address Error (STORE): cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_addr_err_ld(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
#ifdef DEBUG
		kvm_debug("Emulate Load from MMIO space @ %#lx\n", badvaddr);
#endif
		er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
		if (er == EMULATE_FAIL) {
			printk("Emulate Load from MMIO space failed\n");
			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
			ret = RESUME_HOST;
		} else {
			run->exit_reason = KVM_EXIT_MMIO;
			ret = RESUME_HOST;
		}
	} else {
		printk
		    ("Address Error (LOAD): cause %#lx, PC: %p, BadVaddr: %#lx\n",
		     cause, opc, badvaddr);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
		er = EMULATE_FAIL;
	}
	return ret;
}

static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	er = kvm_mips_emulate_syscall(cause, opc, run, vcpu);
	if (er == EMULATE_DONE)
		ret = RESUME_GUEST;
	else {
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_res_inst(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	er = kvm_mips_handle_ri(cause, opc, run, vcpu);
	if (er == EMULATE_DONE)
		ret = RESUME_GUEST;
	else {
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int kvm_trap_emul_handle_break(struct kvm_vcpu *vcpu)
{
	struct kvm_run *run = vcpu->run;
	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
	unsigned long cause = vcpu->arch.host_cp0_cause;
	enum emulation_result er = EMULATE_DONE;
	int ret = RESUME_GUEST;

	er = kvm_mips_emulate_bp_exc(cause, opc, run, vcpu);
	if (er == EMULATE_DONE)
		ret = RESUME_GUEST;
	else {
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		ret = RESUME_HOST;
	}
	return ret;
}

static int
kvm_trap_emul_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	struct mips_coproc *cop0 = vcpu->arch.cop0;

	kvm_write_c0_guest_index(cop0, regs->cp0reg[MIPS_CP0_TLB_INDEX][0]);
	kvm_write_c0_guest_context(cop0, regs->cp0reg[MIPS_CP0_TLB_CONTEXT][0]);
	kvm_write_c0_guest_badvaddr(cop0, regs->cp0reg[MIPS_CP0_BAD_VADDR][0]);
	kvm_write_c0_guest_entryhi(cop0, regs->cp0reg[MIPS_CP0_TLB_HI][0]);
	kvm_write_c0_guest_epc(cop0, regs->cp0reg[MIPS_CP0_EXC_PC][0]);

	kvm_write_c0_guest_status(cop0, regs->cp0reg[MIPS_CP0_STATUS][0]);
	kvm_write_c0_guest_cause(cop0, regs->cp0reg[MIPS_CP0_CAUSE][0]);
	kvm_write_c0_guest_pagemask(cop0,
				    regs->cp0reg[MIPS_CP0_TLB_PG_MASK][0]);
	kvm_write_c0_guest_wired(cop0, regs->cp0reg[MIPS_CP0_TLB_WIRED][0]);
	kvm_write_c0_guest_errorepc(cop0, regs->cp0reg[MIPS_CP0_ERROR_PC][0]);

	return 0;
}

static int
kvm_trap_emul_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	struct mips_coproc *cop0 = vcpu->arch.cop0;

	regs->cp0reg[MIPS_CP0_TLB_INDEX][0] = kvm_read_c0_guest_index(cop0);
	regs->cp0reg[MIPS_CP0_TLB_CONTEXT][0] = kvm_read_c0_guest_context(cop0);
	regs->cp0reg[MIPS_CP0_BAD_VADDR][0] = kvm_read_c0_guest_badvaddr(cop0);
	regs->cp0reg[MIPS_CP0_TLB_HI][0] = kvm_read_c0_guest_entryhi(cop0);
	regs->cp0reg[MIPS_CP0_EXC_PC][0] = kvm_read_c0_guest_epc(cop0);

	regs->cp0reg[MIPS_CP0_STATUS][0] = kvm_read_c0_guest_status(cop0);
	regs->cp0reg[MIPS_CP0_CAUSE][0] = kvm_read_c0_guest_cause(cop0);
	regs->cp0reg[MIPS_CP0_TLB_PG_MASK][0] =
	    kvm_read_c0_guest_pagemask(cop0);
	regs->cp0reg[MIPS_CP0_TLB_WIRED][0] = kvm_read_c0_guest_wired(cop0);
	regs->cp0reg[MIPS_CP0_ERROR_PC][0] = kvm_read_c0_guest_errorepc(cop0);

	regs->cp0reg[MIPS_CP0_CONFIG][0] = kvm_read_c0_guest_config(cop0);
	regs->cp0reg[MIPS_CP0_CONFIG][1] = kvm_read_c0_guest_config1(cop0);
	regs->cp0reg[MIPS_CP0_CONFIG][2] = kvm_read_c0_guest_config2(cop0);
	regs->cp0reg[MIPS_CP0_CONFIG][3] = kvm_read_c0_guest_config3(cop0);
	regs->cp0reg[MIPS_CP0_CONFIG][7] = kvm_read_c0_guest_config7(cop0);

	return 0;
}

static int kvm_trap_emul_vm_init(struct kvm *kvm)
{
	return 0;
}

static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
{
	return 0;
}

static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
{
	struct mips_coproc *cop0 = vcpu->arch.cop0;
	uint32_t config1;
	int vcpu_id = vcpu->vcpu_id;

	/* Arch specific stuff, set up config registers properly so that the
	 * guest will come up as expected, for now we simulate a
	 * MIPS 24kc
	 */
	kvm_write_c0_guest_prid(cop0, 0x00019300);
	kvm_write_c0_guest_config(cop0,
				  MIPS_CONFIG0 | (0x1 << CP0C0_AR) |
				  (MMU_TYPE_R4000 << CP0C0_MT));

	/* Read the cache characteristics from the host Config1 Register */
	config1 = (read_c0_config1() & ~0x7f);

	/* Set up MMU size */
	config1 &= ~(0x3f << 25);
	config1 |= ((KVM_MIPS_GUEST_TLB_SIZE - 1) << 25);

	/* We unset some bits that we aren't emulating */
	config1 &=
	    ~((1 << CP0C1_C2) | (1 << CP0C1_MD) | (1 << CP0C1_PC) |
	      (1 << CP0C1_WR) | (1 << CP0C1_CA));
	kvm_write_c0_guest_config1(cop0, config1);

	kvm_write_c0_guest_config2(cop0, MIPS_CONFIG2);
	/* MIPS_CONFIG2 | (read_c0_config2() & 0xfff) */
	kvm_write_c0_guest_config3(cop0,
				   MIPS_CONFIG3 | (0 << CP0C3_VInt) | (1 <<
								       CP0C3_ULRI));

	/* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
	kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));

	/* Setup IntCtl defaults, compatibilty mode for timer interrupts (HW5) */
	kvm_write_c0_guest_intctl(cop0, 0xFC000000);

	/* Put in vcpu id as CPUNum into Ebase Reg to handle SMP Guests */
	kvm_write_c0_guest_ebase(cop0, KVM_GUEST_KSEG0 | (vcpu_id & 0xFF));

	return 0;
}

static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
	/* exit handlers */
	.handle_cop_unusable = kvm_trap_emul_handle_cop_unusable,
	.handle_tlb_mod = kvm_trap_emul_handle_tlb_mod,
	.handle_tlb_st_miss = kvm_trap_emul_handle_tlb_st_miss,
	.handle_tlb_ld_miss = kvm_trap_emul_handle_tlb_ld_miss,
	.handle_addr_err_st = kvm_trap_emul_handle_addr_err_st,
	.handle_addr_err_ld = kvm_trap_emul_handle_addr_err_ld,
	.handle_syscall = kvm_trap_emul_handle_syscall,
	.handle_res_inst = kvm_trap_emul_handle_res_inst,
	.handle_break = kvm_trap_emul_handle_break,

	.vm_init = kvm_trap_emul_vm_init,
	.vcpu_init = kvm_trap_emul_vcpu_init,
	.vcpu_setup = kvm_trap_emul_vcpu_setup,
	.gva_to_gpa = kvm_trap_emul_gva_to_gpa_cb,
	.queue_timer_int = kvm_mips_queue_timer_int_cb,
	.dequeue_timer_int = kvm_mips_dequeue_timer_int_cb,
	.queue_io_int = kvm_mips_queue_io_int_cb,
	.dequeue_io_int = kvm_mips_dequeue_io_int_cb,
	.irq_deliver = kvm_mips_irq_deliver_cb,
	.irq_clear = kvm_mips_irq_clear_cb,
	.vcpu_ioctl_get_regs = kvm_trap_emul_ioctl_get_regs,
	.vcpu_ioctl_set_regs = kvm_trap_emul_ioctl_set_regs,
};

int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
{
	*install_callbacks = &kvm_trap_emul_callbacks;
	return 0;
}