xref: /openbmc/linux/arch/powerpc/kvm/powerpc.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License, version 2, as
4  * published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9  * GNU General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with this program; if not, write to the Free Software
13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
14  *
15  * Copyright IBM Corp. 2007
16  *
17  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
18  *          Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
19  */
20 
21 #include <linux/errno.h>
22 #include <linux/err.h>
23 #include <linux/kvm_host.h>
24 #include <linux/module.h>
25 #include <linux/vmalloc.h>
26 #include <linux/hrtimer.h>
27 #include <linux/fs.h>
28 #include <linux/slab.h>
29 #include <asm/cputable.h>
30 #include <asm/uaccess.h>
31 #include <asm/kvm_ppc.h>
32 #include <asm/tlbflush.h>
33 #include "timing.h"
34 #include "../mm/mmu_decl.h"
35 
36 #define CREATE_TRACE_POINTS
37 #include "trace.h"
38 
39 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
40 {
41 	return !(v->arch.shared->msr & MSR_WE) ||
42 	       !!(v->arch.pending_exceptions);
43 }
44 
45 int kvmppc_kvm_pv(struct kvm_vcpu *vcpu)
46 {
47 	int nr = kvmppc_get_gpr(vcpu, 11);
48 	int r;
49 	unsigned long __maybe_unused param1 = kvmppc_get_gpr(vcpu, 3);
50 	unsigned long __maybe_unused param2 = kvmppc_get_gpr(vcpu, 4);
51 	unsigned long __maybe_unused param3 = kvmppc_get_gpr(vcpu, 5);
52 	unsigned long __maybe_unused param4 = kvmppc_get_gpr(vcpu, 6);
53 	unsigned long r2 = 0;
54 
55 	if (!(vcpu->arch.shared->msr & MSR_SF)) {
56 		/* 32 bit mode */
57 		param1 &= 0xffffffff;
58 		param2 &= 0xffffffff;
59 		param3 &= 0xffffffff;
60 		param4 &= 0xffffffff;
61 	}
62 
63 	switch (nr) {
64 	case HC_VENDOR_KVM | KVM_HC_PPC_MAP_MAGIC_PAGE:
65 	{
66 		vcpu->arch.magic_page_pa = param1;
67 		vcpu->arch.magic_page_ea = param2;
68 
69 		r2 = KVM_MAGIC_FEAT_SR;
70 
71 		r = HC_EV_SUCCESS;
72 		break;
73 	}
74 	case HC_VENDOR_KVM | KVM_HC_FEATURES:
75 		r = HC_EV_SUCCESS;
76 #if defined(CONFIG_PPC_BOOK3S) /* XXX Missing magic page on BookE */
77 		r2 |= (1 << KVM_FEATURE_MAGIC_PAGE);
78 #endif
79 
80 		/* Second return value is in r4 */
81 		break;
82 	default:
83 		r = HC_EV_UNIMPLEMENTED;
84 		break;
85 	}
86 
87 	kvmppc_set_gpr(vcpu, 4, r2);
88 
89 	return r;
90 }
91 
92 int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
93 {
94 	enum emulation_result er;
95 	int r;
96 
97 	er = kvmppc_emulate_instruction(run, vcpu);
98 	switch (er) {
99 	case EMULATE_DONE:
100 		/* Future optimization: only reload non-volatiles if they were
101 		 * actually modified. */
102 		r = RESUME_GUEST_NV;
103 		break;
104 	case EMULATE_DO_MMIO:
105 		run->exit_reason = KVM_EXIT_MMIO;
106 		/* We must reload nonvolatiles because "update" load/store
107 		 * instructions modify register state. */
108 		/* Future optimization: only reload non-volatiles if they were
109 		 * actually modified. */
110 		r = RESUME_HOST_NV;
111 		break;
112 	case EMULATE_FAIL:
113 		/* XXX Deliver Program interrupt to guest. */
114 		printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
115 		       kvmppc_get_last_inst(vcpu));
116 		r = RESUME_HOST;
117 		break;
118 	default:
119 		BUG();
120 	}
121 
122 	return r;
123 }
124 
125 int kvm_arch_hardware_enable(void *garbage)
126 {
127 	return 0;
128 }
129 
130 void kvm_arch_hardware_disable(void *garbage)
131 {
132 }
133 
134 int kvm_arch_hardware_setup(void)
135 {
136 	return 0;
137 }
138 
139 void kvm_arch_hardware_unsetup(void)
140 {
141 }
142 
143 void kvm_arch_check_processor_compat(void *rtn)
144 {
145 	*(int *)rtn = kvmppc_core_check_processor_compat();
146 }
147 
148 struct kvm *kvm_arch_create_vm(void)
149 {
150 	struct kvm *kvm;
151 
152 	kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
153 	if (!kvm)
154 		return ERR_PTR(-ENOMEM);
155 
156 	return kvm;
157 }
158 
159 static void kvmppc_free_vcpus(struct kvm *kvm)
160 {
161 	unsigned int i;
162 	struct kvm_vcpu *vcpu;
163 
164 	kvm_for_each_vcpu(i, vcpu, kvm)
165 		kvm_arch_vcpu_free(vcpu);
166 
167 	mutex_lock(&kvm->lock);
168 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
169 		kvm->vcpus[i] = NULL;
170 
171 	atomic_set(&kvm->online_vcpus, 0);
172 	mutex_unlock(&kvm->lock);
173 }
174 
175 void kvm_arch_sync_events(struct kvm *kvm)
176 {
177 }
178 
179 void kvm_arch_destroy_vm(struct kvm *kvm)
180 {
181 	kvmppc_free_vcpus(kvm);
182 	kvm_free_physmem(kvm);
183 	cleanup_srcu_struct(&kvm->srcu);
184 	kfree(kvm);
185 }
186 
187 int kvm_dev_ioctl_check_extension(long ext)
188 {
189 	int r;
190 
191 	switch (ext) {
192 	case KVM_CAP_PPC_SEGSTATE:
193 	case KVM_CAP_PPC_PAIRED_SINGLES:
194 	case KVM_CAP_PPC_UNSET_IRQ:
195 	case KVM_CAP_PPC_IRQ_LEVEL:
196 	case KVM_CAP_ENABLE_CAP:
197 	case KVM_CAP_PPC_OSI:
198 	case KVM_CAP_PPC_GET_PVINFO:
199 		r = 1;
200 		break;
201 	case KVM_CAP_COALESCED_MMIO:
202 		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
203 		break;
204 	default:
205 		r = 0;
206 		break;
207 	}
208 	return r;
209 
210 }
211 
212 long kvm_arch_dev_ioctl(struct file *filp,
213                         unsigned int ioctl, unsigned long arg)
214 {
215 	return -EINVAL;
216 }
217 
218 int kvm_arch_prepare_memory_region(struct kvm *kvm,
219                                    struct kvm_memory_slot *memslot,
220                                    struct kvm_memory_slot old,
221                                    struct kvm_userspace_memory_region *mem,
222                                    int user_alloc)
223 {
224 	return 0;
225 }
226 
227 void kvm_arch_commit_memory_region(struct kvm *kvm,
228                struct kvm_userspace_memory_region *mem,
229                struct kvm_memory_slot old,
230                int user_alloc)
231 {
232        return;
233 }
234 
235 
236 void kvm_arch_flush_shadow(struct kvm *kvm)
237 {
238 }
239 
240 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
241 {
242 	struct kvm_vcpu *vcpu;
243 	vcpu = kvmppc_core_vcpu_create(kvm, id);
244 	if (!IS_ERR(vcpu))
245 		kvmppc_create_vcpu_debugfs(vcpu, id);
246 	return vcpu;
247 }
248 
249 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
250 {
251 	/* Make sure we're not using the vcpu anymore */
252 	hrtimer_cancel(&vcpu->arch.dec_timer);
253 	tasklet_kill(&vcpu->arch.tasklet);
254 
255 	kvmppc_remove_vcpu_debugfs(vcpu);
256 	kvmppc_core_vcpu_free(vcpu);
257 }
258 
259 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
260 {
261 	kvm_arch_vcpu_free(vcpu);
262 }
263 
264 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
265 {
266 	return kvmppc_core_pending_dec(vcpu);
267 }
268 
269 static void kvmppc_decrementer_func(unsigned long data)
270 {
271 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
272 
273 	kvmppc_core_queue_dec(vcpu);
274 
275 	if (waitqueue_active(&vcpu->wq)) {
276 		wake_up_interruptible(&vcpu->wq);
277 		vcpu->stat.halt_wakeup++;
278 	}
279 }
280 
281 /*
282  * low level hrtimer wake routine. Because this runs in hardirq context
283  * we schedule a tasklet to do the real work.
284  */
285 enum hrtimer_restart kvmppc_decrementer_wakeup(struct hrtimer *timer)
286 {
287 	struct kvm_vcpu *vcpu;
288 
289 	vcpu = container_of(timer, struct kvm_vcpu, arch.dec_timer);
290 	tasklet_schedule(&vcpu->arch.tasklet);
291 
292 	return HRTIMER_NORESTART;
293 }
294 
295 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
296 {
297 	hrtimer_init(&vcpu->arch.dec_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
298 	tasklet_init(&vcpu->arch.tasklet, kvmppc_decrementer_func, (ulong)vcpu);
299 	vcpu->arch.dec_timer.function = kvmppc_decrementer_wakeup;
300 
301 	return 0;
302 }
303 
304 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
305 {
306 	kvmppc_mmu_destroy(vcpu);
307 }
308 
309 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
310 {
311 	kvmppc_core_vcpu_load(vcpu, cpu);
312 }
313 
314 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
315 {
316 	kvmppc_core_vcpu_put(vcpu);
317 }
318 
319 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
320                                         struct kvm_guest_debug *dbg)
321 {
322 	return -EINVAL;
323 }
324 
325 static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
326                                      struct kvm_run *run)
327 {
328 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, run->dcr.data);
329 }
330 
331 static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
332                                       struct kvm_run *run)
333 {
334 	u64 uninitialized_var(gpr);
335 
336 	if (run->mmio.len > sizeof(gpr)) {
337 		printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
338 		return;
339 	}
340 
341 	if (vcpu->arch.mmio_is_bigendian) {
342 		switch (run->mmio.len) {
343 		case 8: gpr = *(u64 *)run->mmio.data; break;
344 		case 4: gpr = *(u32 *)run->mmio.data; break;
345 		case 2: gpr = *(u16 *)run->mmio.data; break;
346 		case 1: gpr = *(u8 *)run->mmio.data; break;
347 		}
348 	} else {
349 		/* Convert BE data from userland back to LE. */
350 		switch (run->mmio.len) {
351 		case 4: gpr = ld_le32((u32 *)run->mmio.data); break;
352 		case 2: gpr = ld_le16((u16 *)run->mmio.data); break;
353 		case 1: gpr = *(u8 *)run->mmio.data; break;
354 		}
355 	}
356 
357 	if (vcpu->arch.mmio_sign_extend) {
358 		switch (run->mmio.len) {
359 #ifdef CONFIG_PPC64
360 		case 4:
361 			gpr = (s64)(s32)gpr;
362 			break;
363 #endif
364 		case 2:
365 			gpr = (s64)(s16)gpr;
366 			break;
367 		case 1:
368 			gpr = (s64)(s8)gpr;
369 			break;
370 		}
371 	}
372 
373 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
374 
375 	switch (vcpu->arch.io_gpr & KVM_REG_EXT_MASK) {
376 	case KVM_REG_GPR:
377 		kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
378 		break;
379 	case KVM_REG_FPR:
380 		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
381 		break;
382 #ifdef CONFIG_PPC_BOOK3S
383 	case KVM_REG_QPR:
384 		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
385 		break;
386 	case KVM_REG_FQPR:
387 		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
388 		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
389 		break;
390 #endif
391 	default:
392 		BUG();
393 	}
394 }
395 
396 int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
397                        unsigned int rt, unsigned int bytes, int is_bigendian)
398 {
399 	if (bytes > sizeof(run->mmio.data)) {
400 		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
401 		       run->mmio.len);
402 	}
403 
404 	run->mmio.phys_addr = vcpu->arch.paddr_accessed;
405 	run->mmio.len = bytes;
406 	run->mmio.is_write = 0;
407 
408 	vcpu->arch.io_gpr = rt;
409 	vcpu->arch.mmio_is_bigendian = is_bigendian;
410 	vcpu->mmio_needed = 1;
411 	vcpu->mmio_is_write = 0;
412 	vcpu->arch.mmio_sign_extend = 0;
413 
414 	return EMULATE_DO_MMIO;
415 }
416 
417 /* Same as above, but sign extends */
418 int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
419                         unsigned int rt, unsigned int bytes, int is_bigendian)
420 {
421 	int r;
422 
423 	r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
424 	vcpu->arch.mmio_sign_extend = 1;
425 
426 	return r;
427 }
428 
429 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
430                         u64 val, unsigned int bytes, int is_bigendian)
431 {
432 	void *data = run->mmio.data;
433 
434 	if (bytes > sizeof(run->mmio.data)) {
435 		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
436 		       run->mmio.len);
437 	}
438 
439 	run->mmio.phys_addr = vcpu->arch.paddr_accessed;
440 	run->mmio.len = bytes;
441 	run->mmio.is_write = 1;
442 	vcpu->mmio_needed = 1;
443 	vcpu->mmio_is_write = 1;
444 
445 	/* Store the value at the lowest bytes in 'data'. */
446 	if (is_bigendian) {
447 		switch (bytes) {
448 		case 8: *(u64 *)data = val; break;
449 		case 4: *(u32 *)data = val; break;
450 		case 2: *(u16 *)data = val; break;
451 		case 1: *(u8  *)data = val; break;
452 		}
453 	} else {
454 		/* Store LE value into 'data'. */
455 		switch (bytes) {
456 		case 4: st_le32(data, val); break;
457 		case 2: st_le16(data, val); break;
458 		case 1: *(u8 *)data = val; break;
459 		}
460 	}
461 
462 	return EMULATE_DO_MMIO;
463 }
464 
465 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
466 {
467 	int r;
468 	sigset_t sigsaved;
469 
470 	if (vcpu->sigset_active)
471 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
472 
473 	if (vcpu->mmio_needed) {
474 		if (!vcpu->mmio_is_write)
475 			kvmppc_complete_mmio_load(vcpu, run);
476 		vcpu->mmio_needed = 0;
477 	} else if (vcpu->arch.dcr_needed) {
478 		if (!vcpu->arch.dcr_is_write)
479 			kvmppc_complete_dcr_load(vcpu, run);
480 		vcpu->arch.dcr_needed = 0;
481 	} else if (vcpu->arch.osi_needed) {
482 		u64 *gprs = run->osi.gprs;
483 		int i;
484 
485 		for (i = 0; i < 32; i++)
486 			kvmppc_set_gpr(vcpu, i, gprs[i]);
487 		vcpu->arch.osi_needed = 0;
488 	}
489 
490 	kvmppc_core_deliver_interrupts(vcpu);
491 
492 	local_irq_disable();
493 	kvm_guest_enter();
494 	r = __kvmppc_vcpu_run(run, vcpu);
495 	kvm_guest_exit();
496 	local_irq_enable();
497 
498 	if (vcpu->sigset_active)
499 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
500 
501 	return r;
502 }
503 
504 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
505 {
506 	if (irq->irq == KVM_INTERRUPT_UNSET)
507 		kvmppc_core_dequeue_external(vcpu, irq);
508 	else
509 		kvmppc_core_queue_external(vcpu, irq);
510 
511 	if (waitqueue_active(&vcpu->wq)) {
512 		wake_up_interruptible(&vcpu->wq);
513 		vcpu->stat.halt_wakeup++;
514 	}
515 
516 	return 0;
517 }
518 
519 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
520 				     struct kvm_enable_cap *cap)
521 {
522 	int r;
523 
524 	if (cap->flags)
525 		return -EINVAL;
526 
527 	switch (cap->cap) {
528 	case KVM_CAP_PPC_OSI:
529 		r = 0;
530 		vcpu->arch.osi_enabled = true;
531 		break;
532 	default:
533 		r = -EINVAL;
534 		break;
535 	}
536 
537 	return r;
538 }
539 
540 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
541                                     struct kvm_mp_state *mp_state)
542 {
543 	return -EINVAL;
544 }
545 
546 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
547                                     struct kvm_mp_state *mp_state)
548 {
549 	return -EINVAL;
550 }
551 
552 long kvm_arch_vcpu_ioctl(struct file *filp,
553                          unsigned int ioctl, unsigned long arg)
554 {
555 	struct kvm_vcpu *vcpu = filp->private_data;
556 	void __user *argp = (void __user *)arg;
557 	long r;
558 
559 	switch (ioctl) {
560 	case KVM_INTERRUPT: {
561 		struct kvm_interrupt irq;
562 		r = -EFAULT;
563 		if (copy_from_user(&irq, argp, sizeof(irq)))
564 			goto out;
565 		r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
566 		goto out;
567 	}
568 
569 	case KVM_ENABLE_CAP:
570 	{
571 		struct kvm_enable_cap cap;
572 		r = -EFAULT;
573 		if (copy_from_user(&cap, argp, sizeof(cap)))
574 			goto out;
575 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
576 		break;
577 	}
578 	default:
579 		r = -EINVAL;
580 	}
581 
582 out:
583 	return r;
584 }
585 
586 static int kvm_vm_ioctl_get_pvinfo(struct kvm_ppc_pvinfo *pvinfo)
587 {
588 	u32 inst_lis = 0x3c000000;
589 	u32 inst_ori = 0x60000000;
590 	u32 inst_nop = 0x60000000;
591 	u32 inst_sc = 0x44000002;
592 	u32 inst_imm_mask = 0xffff;
593 
594 	/*
595 	 * The hypercall to get into KVM from within guest context is as
596 	 * follows:
597 	 *
598 	 *    lis r0, r0, KVM_SC_MAGIC_R0@h
599 	 *    ori r0, KVM_SC_MAGIC_R0@l
600 	 *    sc
601 	 *    nop
602 	 */
603 	pvinfo->hcall[0] = inst_lis | ((KVM_SC_MAGIC_R0 >> 16) & inst_imm_mask);
604 	pvinfo->hcall[1] = inst_ori | (KVM_SC_MAGIC_R0 & inst_imm_mask);
605 	pvinfo->hcall[2] = inst_sc;
606 	pvinfo->hcall[3] = inst_nop;
607 
608 	return 0;
609 }
610 
611 long kvm_arch_vm_ioctl(struct file *filp,
612                        unsigned int ioctl, unsigned long arg)
613 {
614 	void __user *argp = (void __user *)arg;
615 	long r;
616 
617 	switch (ioctl) {
618 	case KVM_PPC_GET_PVINFO: {
619 		struct kvm_ppc_pvinfo pvinfo;
620 		memset(&pvinfo, 0, sizeof(pvinfo));
621 		r = kvm_vm_ioctl_get_pvinfo(&pvinfo);
622 		if (copy_to_user(argp, &pvinfo, sizeof(pvinfo))) {
623 			r = -EFAULT;
624 			goto out;
625 		}
626 
627 		break;
628 	}
629 	default:
630 		r = -ENOTTY;
631 	}
632 
633 out:
634 	return r;
635 }
636 
637 int kvm_arch_init(void *opaque)
638 {
639 	return 0;
640 }
641 
642 void kvm_arch_exit(void)
643 {
644 }
645