xref: /openbmc/linux/arch/powerpc/kvm/powerpc.c (revision 54525552)
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 int kvm_arch_init_vm(struct kvm *kvm)
149 {
150 	return 0;
151 }
152 
153 void kvm_arch_destroy_vm(struct kvm *kvm)
154 {
155 	unsigned int i;
156 	struct kvm_vcpu *vcpu;
157 
158 	kvm_for_each_vcpu(i, vcpu, kvm)
159 		kvm_arch_vcpu_free(vcpu);
160 
161 	mutex_lock(&kvm->lock);
162 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
163 		kvm->vcpus[i] = NULL;
164 
165 	atomic_set(&kvm->online_vcpus, 0);
166 	mutex_unlock(&kvm->lock);
167 }
168 
169 void kvm_arch_sync_events(struct kvm *kvm)
170 {
171 }
172 
173 int kvm_dev_ioctl_check_extension(long ext)
174 {
175 	int r;
176 
177 	switch (ext) {
178 #ifdef CONFIG_BOOKE
179 	case KVM_CAP_PPC_BOOKE_SREGS:
180 #else
181 	case KVM_CAP_PPC_SEGSTATE:
182 #endif
183 	case KVM_CAP_PPC_PAIRED_SINGLES:
184 	case KVM_CAP_PPC_UNSET_IRQ:
185 	case KVM_CAP_PPC_IRQ_LEVEL:
186 	case KVM_CAP_ENABLE_CAP:
187 	case KVM_CAP_PPC_OSI:
188 	case KVM_CAP_PPC_GET_PVINFO:
189 		r = 1;
190 		break;
191 	case KVM_CAP_COALESCED_MMIO:
192 		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
193 		break;
194 	default:
195 		r = 0;
196 		break;
197 	}
198 	return r;
199 
200 }
201 
202 long kvm_arch_dev_ioctl(struct file *filp,
203                         unsigned int ioctl, unsigned long arg)
204 {
205 	return -EINVAL;
206 }
207 
208 int kvm_arch_prepare_memory_region(struct kvm *kvm,
209                                    struct kvm_memory_slot *memslot,
210                                    struct kvm_memory_slot old,
211                                    struct kvm_userspace_memory_region *mem,
212                                    int user_alloc)
213 {
214 	return 0;
215 }
216 
217 void kvm_arch_commit_memory_region(struct kvm *kvm,
218                struct kvm_userspace_memory_region *mem,
219                struct kvm_memory_slot old,
220                int user_alloc)
221 {
222        return;
223 }
224 
225 
226 void kvm_arch_flush_shadow(struct kvm *kvm)
227 {
228 }
229 
230 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
231 {
232 	struct kvm_vcpu *vcpu;
233 	vcpu = kvmppc_core_vcpu_create(kvm, id);
234 	if (!IS_ERR(vcpu))
235 		kvmppc_create_vcpu_debugfs(vcpu, id);
236 	return vcpu;
237 }
238 
239 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
240 {
241 	/* Make sure we're not using the vcpu anymore */
242 	hrtimer_cancel(&vcpu->arch.dec_timer);
243 	tasklet_kill(&vcpu->arch.tasklet);
244 
245 	kvmppc_remove_vcpu_debugfs(vcpu);
246 	kvmppc_core_vcpu_free(vcpu);
247 }
248 
249 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
250 {
251 	kvm_arch_vcpu_free(vcpu);
252 }
253 
254 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
255 {
256 	return kvmppc_core_pending_dec(vcpu);
257 }
258 
259 static void kvmppc_decrementer_func(unsigned long data)
260 {
261 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
262 
263 	kvmppc_core_queue_dec(vcpu);
264 
265 	if (waitqueue_active(&vcpu->wq)) {
266 		wake_up_interruptible(&vcpu->wq);
267 		vcpu->stat.halt_wakeup++;
268 	}
269 }
270 
271 /*
272  * low level hrtimer wake routine. Because this runs in hardirq context
273  * we schedule a tasklet to do the real work.
274  */
275 enum hrtimer_restart kvmppc_decrementer_wakeup(struct hrtimer *timer)
276 {
277 	struct kvm_vcpu *vcpu;
278 
279 	vcpu = container_of(timer, struct kvm_vcpu, arch.dec_timer);
280 	tasklet_schedule(&vcpu->arch.tasklet);
281 
282 	return HRTIMER_NORESTART;
283 }
284 
285 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
286 {
287 	hrtimer_init(&vcpu->arch.dec_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
288 	tasklet_init(&vcpu->arch.tasklet, kvmppc_decrementer_func, (ulong)vcpu);
289 	vcpu->arch.dec_timer.function = kvmppc_decrementer_wakeup;
290 
291 #ifdef CONFIG_KVM_EXIT_TIMING
292 	mutex_init(&vcpu->arch.exit_timing_lock);
293 #endif
294 
295 	return 0;
296 }
297 
298 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
299 {
300 	kvmppc_mmu_destroy(vcpu);
301 }
302 
303 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
304 {
305 #ifdef CONFIG_BOOKE
306 	/*
307 	 * vrsave (formerly usprg0) isn't used by Linux, but may
308 	 * be used by the guest.
309 	 *
310 	 * On non-booke this is associated with Altivec and
311 	 * is handled by code in book3s.c.
312 	 */
313 	mtspr(SPRN_VRSAVE, vcpu->arch.vrsave);
314 #endif
315 	kvmppc_core_vcpu_load(vcpu, cpu);
316 }
317 
318 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
319 {
320 	kvmppc_core_vcpu_put(vcpu);
321 #ifdef CONFIG_BOOKE
322 	vcpu->arch.vrsave = mfspr(SPRN_VRSAVE);
323 #endif
324 }
325 
326 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
327                                         struct kvm_guest_debug *dbg)
328 {
329 	return -EINVAL;
330 }
331 
332 static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
333                                      struct kvm_run *run)
334 {
335 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, run->dcr.data);
336 }
337 
338 static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
339                                       struct kvm_run *run)
340 {
341 	u64 uninitialized_var(gpr);
342 
343 	if (run->mmio.len > sizeof(gpr)) {
344 		printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
345 		return;
346 	}
347 
348 	if (vcpu->arch.mmio_is_bigendian) {
349 		switch (run->mmio.len) {
350 		case 8: gpr = *(u64 *)run->mmio.data; break;
351 		case 4: gpr = *(u32 *)run->mmio.data; break;
352 		case 2: gpr = *(u16 *)run->mmio.data; break;
353 		case 1: gpr = *(u8 *)run->mmio.data; break;
354 		}
355 	} else {
356 		/* Convert BE data from userland back to LE. */
357 		switch (run->mmio.len) {
358 		case 4: gpr = ld_le32((u32 *)run->mmio.data); break;
359 		case 2: gpr = ld_le16((u16 *)run->mmio.data); break;
360 		case 1: gpr = *(u8 *)run->mmio.data; break;
361 		}
362 	}
363 
364 	if (vcpu->arch.mmio_sign_extend) {
365 		switch (run->mmio.len) {
366 #ifdef CONFIG_PPC64
367 		case 4:
368 			gpr = (s64)(s32)gpr;
369 			break;
370 #endif
371 		case 2:
372 			gpr = (s64)(s16)gpr;
373 			break;
374 		case 1:
375 			gpr = (s64)(s8)gpr;
376 			break;
377 		}
378 	}
379 
380 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
381 
382 	switch (vcpu->arch.io_gpr & KVM_REG_EXT_MASK) {
383 	case KVM_REG_GPR:
384 		kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
385 		break;
386 	case KVM_REG_FPR:
387 		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
388 		break;
389 #ifdef CONFIG_PPC_BOOK3S
390 	case KVM_REG_QPR:
391 		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
392 		break;
393 	case KVM_REG_FQPR:
394 		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
395 		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
396 		break;
397 #endif
398 	default:
399 		BUG();
400 	}
401 }
402 
403 int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
404                        unsigned int rt, unsigned int bytes, int is_bigendian)
405 {
406 	if (bytes > sizeof(run->mmio.data)) {
407 		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
408 		       run->mmio.len);
409 	}
410 
411 	run->mmio.phys_addr = vcpu->arch.paddr_accessed;
412 	run->mmio.len = bytes;
413 	run->mmio.is_write = 0;
414 
415 	vcpu->arch.io_gpr = rt;
416 	vcpu->arch.mmio_is_bigendian = is_bigendian;
417 	vcpu->mmio_needed = 1;
418 	vcpu->mmio_is_write = 0;
419 	vcpu->arch.mmio_sign_extend = 0;
420 
421 	return EMULATE_DO_MMIO;
422 }
423 
424 /* Same as above, but sign extends */
425 int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
426                         unsigned int rt, unsigned int bytes, int is_bigendian)
427 {
428 	int r;
429 
430 	r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
431 	vcpu->arch.mmio_sign_extend = 1;
432 
433 	return r;
434 }
435 
436 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
437                         u64 val, unsigned int bytes, int is_bigendian)
438 {
439 	void *data = run->mmio.data;
440 
441 	if (bytes > sizeof(run->mmio.data)) {
442 		printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
443 		       run->mmio.len);
444 	}
445 
446 	run->mmio.phys_addr = vcpu->arch.paddr_accessed;
447 	run->mmio.len = bytes;
448 	run->mmio.is_write = 1;
449 	vcpu->mmio_needed = 1;
450 	vcpu->mmio_is_write = 1;
451 
452 	/* Store the value at the lowest bytes in 'data'. */
453 	if (is_bigendian) {
454 		switch (bytes) {
455 		case 8: *(u64 *)data = val; break;
456 		case 4: *(u32 *)data = val; break;
457 		case 2: *(u16 *)data = val; break;
458 		case 1: *(u8  *)data = val; break;
459 		}
460 	} else {
461 		/* Store LE value into 'data'. */
462 		switch (bytes) {
463 		case 4: st_le32(data, val); break;
464 		case 2: st_le16(data, val); break;
465 		case 1: *(u8 *)data = val; break;
466 		}
467 	}
468 
469 	return EMULATE_DO_MMIO;
470 }
471 
472 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
473 {
474 	int r;
475 	sigset_t sigsaved;
476 
477 	if (vcpu->sigset_active)
478 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
479 
480 	if (vcpu->mmio_needed) {
481 		if (!vcpu->mmio_is_write)
482 			kvmppc_complete_mmio_load(vcpu, run);
483 		vcpu->mmio_needed = 0;
484 	} else if (vcpu->arch.dcr_needed) {
485 		if (!vcpu->arch.dcr_is_write)
486 			kvmppc_complete_dcr_load(vcpu, run);
487 		vcpu->arch.dcr_needed = 0;
488 	} else if (vcpu->arch.osi_needed) {
489 		u64 *gprs = run->osi.gprs;
490 		int i;
491 
492 		for (i = 0; i < 32; i++)
493 			kvmppc_set_gpr(vcpu, i, gprs[i]);
494 		vcpu->arch.osi_needed = 0;
495 	}
496 
497 	kvmppc_core_deliver_interrupts(vcpu);
498 
499 	local_irq_disable();
500 	kvm_guest_enter();
501 	r = __kvmppc_vcpu_run(run, vcpu);
502 	kvm_guest_exit();
503 	local_irq_enable();
504 
505 	if (vcpu->sigset_active)
506 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
507 
508 	return r;
509 }
510 
511 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
512 {
513 	if (irq->irq == KVM_INTERRUPT_UNSET)
514 		kvmppc_core_dequeue_external(vcpu, irq);
515 	else
516 		kvmppc_core_queue_external(vcpu, irq);
517 
518 	if (waitqueue_active(&vcpu->wq)) {
519 		wake_up_interruptible(&vcpu->wq);
520 		vcpu->stat.halt_wakeup++;
521 	}
522 
523 	return 0;
524 }
525 
526 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
527 				     struct kvm_enable_cap *cap)
528 {
529 	int r;
530 
531 	if (cap->flags)
532 		return -EINVAL;
533 
534 	switch (cap->cap) {
535 	case KVM_CAP_PPC_OSI:
536 		r = 0;
537 		vcpu->arch.osi_enabled = true;
538 		break;
539 	default:
540 		r = -EINVAL;
541 		break;
542 	}
543 
544 	return r;
545 }
546 
547 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
548                                     struct kvm_mp_state *mp_state)
549 {
550 	return -EINVAL;
551 }
552 
553 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
554                                     struct kvm_mp_state *mp_state)
555 {
556 	return -EINVAL;
557 }
558 
559 long kvm_arch_vcpu_ioctl(struct file *filp,
560                          unsigned int ioctl, unsigned long arg)
561 {
562 	struct kvm_vcpu *vcpu = filp->private_data;
563 	void __user *argp = (void __user *)arg;
564 	long r;
565 
566 	switch (ioctl) {
567 	case KVM_INTERRUPT: {
568 		struct kvm_interrupt irq;
569 		r = -EFAULT;
570 		if (copy_from_user(&irq, argp, sizeof(irq)))
571 			goto out;
572 		r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
573 		goto out;
574 	}
575 
576 	case KVM_ENABLE_CAP:
577 	{
578 		struct kvm_enable_cap cap;
579 		r = -EFAULT;
580 		if (copy_from_user(&cap, argp, sizeof(cap)))
581 			goto out;
582 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
583 		break;
584 	}
585 	default:
586 		r = -EINVAL;
587 	}
588 
589 out:
590 	return r;
591 }
592 
593 static int kvm_vm_ioctl_get_pvinfo(struct kvm_ppc_pvinfo *pvinfo)
594 {
595 	u32 inst_lis = 0x3c000000;
596 	u32 inst_ori = 0x60000000;
597 	u32 inst_nop = 0x60000000;
598 	u32 inst_sc = 0x44000002;
599 	u32 inst_imm_mask = 0xffff;
600 
601 	/*
602 	 * The hypercall to get into KVM from within guest context is as
603 	 * follows:
604 	 *
605 	 *    lis r0, r0, KVM_SC_MAGIC_R0@h
606 	 *    ori r0, KVM_SC_MAGIC_R0@l
607 	 *    sc
608 	 *    nop
609 	 */
610 	pvinfo->hcall[0] = inst_lis | ((KVM_SC_MAGIC_R0 >> 16) & inst_imm_mask);
611 	pvinfo->hcall[1] = inst_ori | (KVM_SC_MAGIC_R0 & inst_imm_mask);
612 	pvinfo->hcall[2] = inst_sc;
613 	pvinfo->hcall[3] = inst_nop;
614 
615 	return 0;
616 }
617 
618 long kvm_arch_vm_ioctl(struct file *filp,
619                        unsigned int ioctl, unsigned long arg)
620 {
621 	void __user *argp = (void __user *)arg;
622 	long r;
623 
624 	switch (ioctl) {
625 	case KVM_PPC_GET_PVINFO: {
626 		struct kvm_ppc_pvinfo pvinfo;
627 		memset(&pvinfo, 0, sizeof(pvinfo));
628 		r = kvm_vm_ioctl_get_pvinfo(&pvinfo);
629 		if (copy_to_user(argp, &pvinfo, sizeof(pvinfo))) {
630 			r = -EFAULT;
631 			goto out;
632 		}
633 
634 		break;
635 	}
636 	default:
637 		r = -ENOTTY;
638 	}
639 
640 out:
641 	return r;
642 }
643 
644 int kvm_arch_init(void *opaque)
645 {
646 	return 0;
647 }
648 
649 void kvm_arch_exit(void)
650 {
651 }
652