70664f020849bfcc3a674530d73a314124361c68
[safe/jmp/linux-2.6] / drivers / kvm / kvm_main.c
1 /*
2  * Kernel-based Virtual Machine driver for Linux
3  *
4  * This module enables machines with Intel VT-x extensions to run virtual
5  * machines without emulation or binary translation.
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  *
9  * Authors:
10  *   Avi Kivity   <avi@qumranet.com>
11  *   Yaniv Kamay  <yaniv@qumranet.com>
12  *
13  * This work is licensed under the terms of the GNU GPL, version 2.  See
14  * the COPYING file in the top-level directory.
15  *
16  */
17
18 #include "kvm.h"
19 #include "iodev.h"
20
21 #include <linux/kvm.h>
22 #include <linux/module.h>
23 #include <linux/errno.h>
24 #include <linux/percpu.h>
25 #include <linux/gfp.h>
26 #include <linux/mm.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/sysdev.h>
34 #include <linux/cpu.h>
35 #include <linux/sched.h>
36 #include <linux/cpumask.h>
37 #include <linux/smp.h>
38 #include <linux/anon_inodes.h>
39 #include <linux/profile.h>
40 #include <linux/kvm_para.h>
41 #include <linux/pagemap.h>
42 #include <linux/mman.h>
43
44 #include <asm/processor.h>
45 #include <asm/io.h>
46 #include <asm/uaccess.h>
47 #include <asm/pgtable.h>
48
49 MODULE_AUTHOR("Qumranet");
50 MODULE_LICENSE("GPL");
51
52 DEFINE_SPINLOCK(kvm_lock);
53 LIST_HEAD(vm_list);
54
55 static cpumask_t cpus_hardware_enabled;
56
57 struct kmem_cache *kvm_vcpu_cache;
58 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
59
60 static __read_mostly struct preempt_ops kvm_preempt_ops;
61
62 static struct dentry *debugfs_dir;
63
64 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
65                            unsigned long arg);
66
67 static inline int valid_vcpu(int n)
68 {
69         return likely(n >= 0 && n < KVM_MAX_VCPUS);
70 }
71
72 /*
73  * Switches to specified vcpu, until a matching vcpu_put()
74  */
75 void vcpu_load(struct kvm_vcpu *vcpu)
76 {
77         int cpu;
78
79         mutex_lock(&vcpu->mutex);
80         cpu = get_cpu();
81         preempt_notifier_register(&vcpu->preempt_notifier);
82         kvm_arch_vcpu_load(vcpu, cpu);
83         put_cpu();
84 }
85
86 void vcpu_put(struct kvm_vcpu *vcpu)
87 {
88         preempt_disable();
89         kvm_arch_vcpu_put(vcpu);
90         preempt_notifier_unregister(&vcpu->preempt_notifier);
91         preempt_enable();
92         mutex_unlock(&vcpu->mutex);
93 }
94
95 static void ack_flush(void *_completed)
96 {
97 }
98
99 void kvm_flush_remote_tlbs(struct kvm *kvm)
100 {
101         int i, cpu;
102         cpumask_t cpus;
103         struct kvm_vcpu *vcpu;
104
105         cpus_clear(cpus);
106         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
107                 vcpu = kvm->vcpus[i];
108                 if (!vcpu)
109                         continue;
110                 if (test_and_set_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
111                         continue;
112                 cpu = vcpu->cpu;
113                 if (cpu != -1 && cpu != raw_smp_processor_id())
114                         cpu_set(cpu, cpus);
115         }
116         if (cpus_empty(cpus))
117                 return;
118         ++kvm->stat.remote_tlb_flush;
119         smp_call_function_mask(cpus, ack_flush, NULL, 1);
120 }
121
122 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
123 {
124         struct page *page;
125         int r;
126
127         mutex_init(&vcpu->mutex);
128         vcpu->cpu = -1;
129         vcpu->kvm = kvm;
130         vcpu->vcpu_id = id;
131         init_waitqueue_head(&vcpu->wq);
132
133         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
134         if (!page) {
135                 r = -ENOMEM;
136                 goto fail;
137         }
138         vcpu->run = page_address(page);
139
140         r = kvm_arch_vcpu_init(vcpu);
141         if (r < 0)
142                 goto fail_free_run;
143         return 0;
144
145 fail_free_run:
146         free_page((unsigned long)vcpu->run);
147 fail:
148         return r;
149 }
150 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
151
152 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
153 {
154         kvm_arch_vcpu_uninit(vcpu);
155         free_page((unsigned long)vcpu->run);
156 }
157 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
158
159 static struct kvm *kvm_create_vm(void)
160 {
161         struct kvm *kvm = kvm_arch_create_vm();
162
163         if (IS_ERR(kvm))
164                 goto out;
165
166         kvm->mm = current->mm;
167         atomic_inc(&kvm->mm->mm_count);
168         kvm_io_bus_init(&kvm->pio_bus);
169         mutex_init(&kvm->lock);
170         kvm_io_bus_init(&kvm->mmio_bus);
171         spin_lock(&kvm_lock);
172         list_add(&kvm->vm_list, &vm_list);
173         spin_unlock(&kvm_lock);
174 out:
175         return kvm;
176 }
177
178 /*
179  * Free any memory in @free but not in @dont.
180  */
181 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
182                                   struct kvm_memory_slot *dont)
183 {
184         if (!dont || free->rmap != dont->rmap)
185                 vfree(free->rmap);
186
187         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
188                 vfree(free->dirty_bitmap);
189
190         free->npages = 0;
191         free->dirty_bitmap = NULL;
192         free->rmap = NULL;
193 }
194
195 void kvm_free_physmem(struct kvm *kvm)
196 {
197         int i;
198
199         for (i = 0; i < kvm->nmemslots; ++i)
200                 kvm_free_physmem_slot(&kvm->memslots[i], NULL);
201 }
202
203 static void kvm_destroy_vm(struct kvm *kvm)
204 {
205         struct mm_struct *mm = kvm->mm;
206
207         spin_lock(&kvm_lock);
208         list_del(&kvm->vm_list);
209         spin_unlock(&kvm_lock);
210         kvm_io_bus_destroy(&kvm->pio_bus);
211         kvm_io_bus_destroy(&kvm->mmio_bus);
212         kvm_arch_destroy_vm(kvm);
213         mmdrop(mm);
214 }
215
216 static int kvm_vm_release(struct inode *inode, struct file *filp)
217 {
218         struct kvm *kvm = filp->private_data;
219
220         kvm_destroy_vm(kvm);
221         return 0;
222 }
223
224 /*
225  * Allocate some memory and give it an address in the guest physical address
226  * space.
227  *
228  * Discontiguous memory is allowed, mostly for framebuffers.
229  *
230  * Must be called holding kvm->lock.
231  */
232 int __kvm_set_memory_region(struct kvm *kvm,
233                             struct kvm_userspace_memory_region *mem,
234                             int user_alloc)
235 {
236         int r;
237         gfn_t base_gfn;
238         unsigned long npages;
239         unsigned long i;
240         struct kvm_memory_slot *memslot;
241         struct kvm_memory_slot old, new;
242
243         r = -EINVAL;
244         /* General sanity checks */
245         if (mem->memory_size & (PAGE_SIZE - 1))
246                 goto out;
247         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
248                 goto out;
249         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
250                 goto out;
251         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
252                 goto out;
253
254         memslot = &kvm->memslots[mem->slot];
255         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
256         npages = mem->memory_size >> PAGE_SHIFT;
257
258         if (!npages)
259                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
260
261         new = old = *memslot;
262
263         new.base_gfn = base_gfn;
264         new.npages = npages;
265         new.flags = mem->flags;
266
267         /* Disallow changing a memory slot's size. */
268         r = -EINVAL;
269         if (npages && old.npages && npages != old.npages)
270                 goto out_free;
271
272         /* Check for overlaps */
273         r = -EEXIST;
274         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
275                 struct kvm_memory_slot *s = &kvm->memslots[i];
276
277                 if (s == memslot)
278                         continue;
279                 if (!((base_gfn + npages <= s->base_gfn) ||
280                       (base_gfn >= s->base_gfn + s->npages)))
281                         goto out_free;
282         }
283
284         /* Free page dirty bitmap if unneeded */
285         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
286                 new.dirty_bitmap = NULL;
287
288         r = -ENOMEM;
289
290         /* Allocate if a slot is being created */
291         if (npages && !new.rmap) {
292                 new.rmap = vmalloc(npages * sizeof(struct page *));
293
294                 if (!new.rmap)
295                         goto out_free;
296
297                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
298
299                 new.user_alloc = user_alloc;
300                 new.userspace_addr = mem->userspace_addr;
301         }
302
303         /* Allocate page dirty bitmap if needed */
304         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
305                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
306
307                 new.dirty_bitmap = vmalloc(dirty_bytes);
308                 if (!new.dirty_bitmap)
309                         goto out_free;
310                 memset(new.dirty_bitmap, 0, dirty_bytes);
311         }
312
313         if (mem->slot >= kvm->nmemslots)
314                 kvm->nmemslots = mem->slot + 1;
315
316         *memslot = new;
317
318         r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
319         if (r) {
320                 *memslot = old;
321                 goto out_free;
322         }
323
324         kvm_free_physmem_slot(&old, &new);
325         return 0;
326
327 out_free:
328         kvm_free_physmem_slot(&new, &old);
329 out:
330         return r;
331
332 }
333 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
334
335 int kvm_set_memory_region(struct kvm *kvm,
336                           struct kvm_userspace_memory_region *mem,
337                           int user_alloc)
338 {
339         int r;
340
341         mutex_lock(&kvm->lock);
342         r = __kvm_set_memory_region(kvm, mem, user_alloc);
343         mutex_unlock(&kvm->lock);
344         return r;
345 }
346 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
347
348 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
349                                    struct
350                                    kvm_userspace_memory_region *mem,
351                                    int user_alloc)
352 {
353         if (mem->slot >= KVM_MEMORY_SLOTS)
354                 return -EINVAL;
355         return kvm_set_memory_region(kvm, mem, user_alloc);
356 }
357
358 int kvm_get_dirty_log(struct kvm *kvm,
359                         struct kvm_dirty_log *log, int *is_dirty)
360 {
361         struct kvm_memory_slot *memslot;
362         int r, i;
363         int n;
364         unsigned long any = 0;
365
366         r = -EINVAL;
367         if (log->slot >= KVM_MEMORY_SLOTS)
368                 goto out;
369
370         memslot = &kvm->memslots[log->slot];
371         r = -ENOENT;
372         if (!memslot->dirty_bitmap)
373                 goto out;
374
375         n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
376
377         for (i = 0; !any && i < n/sizeof(long); ++i)
378                 any = memslot->dirty_bitmap[i];
379
380         r = -EFAULT;
381         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
382                 goto out;
383
384         if (any)
385                 *is_dirty = 1;
386
387         r = 0;
388 out:
389         return r;
390 }
391
392 int is_error_page(struct page *page)
393 {
394         return page == bad_page;
395 }
396 EXPORT_SYMBOL_GPL(is_error_page);
397
398 static inline unsigned long bad_hva(void)
399 {
400         return PAGE_OFFSET;
401 }
402
403 int kvm_is_error_hva(unsigned long addr)
404 {
405         return addr == bad_hva();
406 }
407 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
408
409 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
410 {
411         int i;
412
413         for (i = 0; i < kvm->nmemslots; ++i) {
414                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
415
416                 if (gfn >= memslot->base_gfn
417                     && gfn < memslot->base_gfn + memslot->npages)
418                         return memslot;
419         }
420         return NULL;
421 }
422
423 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
424 {
425         gfn = unalias_gfn(kvm, gfn);
426         return __gfn_to_memslot(kvm, gfn);
427 }
428
429 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
430 {
431         int i;
432
433         gfn = unalias_gfn(kvm, gfn);
434         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
435                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
436
437                 if (gfn >= memslot->base_gfn
438                     && gfn < memslot->base_gfn + memslot->npages)
439                         return 1;
440         }
441         return 0;
442 }
443 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
444
445 static unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
446 {
447         struct kvm_memory_slot *slot;
448
449         gfn = unalias_gfn(kvm, gfn);
450         slot = __gfn_to_memslot(kvm, gfn);
451         if (!slot)
452                 return bad_hva();
453         return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
454 }
455
456 /*
457  * Requires current->mm->mmap_sem to be held
458  */
459 static struct page *__gfn_to_page(struct kvm *kvm, gfn_t gfn)
460 {
461         struct page *page[1];
462         unsigned long addr;
463         int npages;
464
465         might_sleep();
466
467         addr = gfn_to_hva(kvm, gfn);
468         if (kvm_is_error_hva(addr)) {
469                 get_page(bad_page);
470                 return bad_page;
471         }
472
473         npages = get_user_pages(current, current->mm, addr, 1, 1, 1, page,
474                                 NULL);
475
476         if (npages != 1) {
477                 get_page(bad_page);
478                 return bad_page;
479         }
480
481         return page[0];
482 }
483
484 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
485 {
486         struct page *page;
487
488         down_read(&current->mm->mmap_sem);
489         page = __gfn_to_page(kvm, gfn);
490         up_read(&current->mm->mmap_sem);
491
492         return page;
493 }
494
495 EXPORT_SYMBOL_GPL(gfn_to_page);
496
497 void kvm_release_page_clean(struct page *page)
498 {
499         put_page(page);
500 }
501 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
502
503 void kvm_release_page_dirty(struct page *page)
504 {
505         if (!PageReserved(page))
506                 SetPageDirty(page);
507         put_page(page);
508 }
509 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
510
511 static int next_segment(unsigned long len, int offset)
512 {
513         if (len > PAGE_SIZE - offset)
514                 return PAGE_SIZE - offset;
515         else
516                 return len;
517 }
518
519 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
520                         int len)
521 {
522         int r;
523         unsigned long addr;
524
525         addr = gfn_to_hva(kvm, gfn);
526         if (kvm_is_error_hva(addr))
527                 return -EFAULT;
528         r = copy_from_user(data, (void __user *)addr + offset, len);
529         if (r)
530                 return -EFAULT;
531         return 0;
532 }
533 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
534
535 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
536 {
537         gfn_t gfn = gpa >> PAGE_SHIFT;
538         int seg;
539         int offset = offset_in_page(gpa);
540         int ret;
541
542         while ((seg = next_segment(len, offset)) != 0) {
543                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
544                 if (ret < 0)
545                         return ret;
546                 offset = 0;
547                 len -= seg;
548                 data += seg;
549                 ++gfn;
550         }
551         return 0;
552 }
553 EXPORT_SYMBOL_GPL(kvm_read_guest);
554
555 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
556                          int offset, int len)
557 {
558         int r;
559         unsigned long addr;
560
561         addr = gfn_to_hva(kvm, gfn);
562         if (kvm_is_error_hva(addr))
563                 return -EFAULT;
564         r = copy_to_user((void __user *)addr + offset, data, len);
565         if (r)
566                 return -EFAULT;
567         mark_page_dirty(kvm, gfn);
568         return 0;
569 }
570 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
571
572 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
573                     unsigned long len)
574 {
575         gfn_t gfn = gpa >> PAGE_SHIFT;
576         int seg;
577         int offset = offset_in_page(gpa);
578         int ret;
579
580         while ((seg = next_segment(len, offset)) != 0) {
581                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
582                 if (ret < 0)
583                         return ret;
584                 offset = 0;
585                 len -= seg;
586                 data += seg;
587                 ++gfn;
588         }
589         return 0;
590 }
591
592 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
593 {
594         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
595 }
596 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
597
598 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
599 {
600         gfn_t gfn = gpa >> PAGE_SHIFT;
601         int seg;
602         int offset = offset_in_page(gpa);
603         int ret;
604
605         while ((seg = next_segment(len, offset)) != 0) {
606                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
607                 if (ret < 0)
608                         return ret;
609                 offset = 0;
610                 len -= seg;
611                 ++gfn;
612         }
613         return 0;
614 }
615 EXPORT_SYMBOL_GPL(kvm_clear_guest);
616
617 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
618 {
619         struct kvm_memory_slot *memslot;
620
621         gfn = unalias_gfn(kvm, gfn);
622         memslot = __gfn_to_memslot(kvm, gfn);
623         if (memslot && memslot->dirty_bitmap) {
624                 unsigned long rel_gfn = gfn - memslot->base_gfn;
625
626                 /* avoid RMW */
627                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
628                         set_bit(rel_gfn, memslot->dirty_bitmap);
629         }
630 }
631
632 /*
633  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
634  */
635 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
636 {
637         DECLARE_WAITQUEUE(wait, current);
638
639         add_wait_queue(&vcpu->wq, &wait);
640
641         /*
642          * We will block until either an interrupt or a signal wakes us up
643          */
644         while (!kvm_cpu_has_interrupt(vcpu)
645                && !signal_pending(current)
646                && !kvm_arch_vcpu_runnable(vcpu)) {
647                 set_current_state(TASK_INTERRUPTIBLE);
648                 vcpu_put(vcpu);
649                 schedule();
650                 vcpu_load(vcpu);
651         }
652
653         __set_current_state(TASK_RUNNING);
654         remove_wait_queue(&vcpu->wq, &wait);
655 }
656
657 void kvm_resched(struct kvm_vcpu *vcpu)
658 {
659         if (!need_resched())
660                 return;
661         cond_resched();
662 }
663 EXPORT_SYMBOL_GPL(kvm_resched);
664
665 static struct page *kvm_vcpu_nopage(struct vm_area_struct *vma,
666                                     unsigned long address,
667                                     int *type)
668 {
669         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
670         unsigned long pgoff;
671         struct page *page;
672
673         pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
674         if (pgoff == 0)
675                 page = virt_to_page(vcpu->run);
676         else if (pgoff == KVM_PIO_PAGE_OFFSET)
677                 page = virt_to_page(vcpu->pio_data);
678         else
679                 return NOPAGE_SIGBUS;
680         get_page(page);
681         if (type != NULL)
682                 *type = VM_FAULT_MINOR;
683
684         return page;
685 }
686
687 static struct vm_operations_struct kvm_vcpu_vm_ops = {
688         .nopage = kvm_vcpu_nopage,
689 };
690
691 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
692 {
693         vma->vm_ops = &kvm_vcpu_vm_ops;
694         return 0;
695 }
696
697 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
698 {
699         struct kvm_vcpu *vcpu = filp->private_data;
700
701         fput(vcpu->kvm->filp);
702         return 0;
703 }
704
705 static struct file_operations kvm_vcpu_fops = {
706         .release        = kvm_vcpu_release,
707         .unlocked_ioctl = kvm_vcpu_ioctl,
708         .compat_ioctl   = kvm_vcpu_ioctl,
709         .mmap           = kvm_vcpu_mmap,
710 };
711
712 /*
713  * Allocates an inode for the vcpu.
714  */
715 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
716 {
717         int fd, r;
718         struct inode *inode;
719         struct file *file;
720
721         r = anon_inode_getfd(&fd, &inode, &file,
722                              "kvm-vcpu", &kvm_vcpu_fops, vcpu);
723         if (r)
724                 return r;
725         atomic_inc(&vcpu->kvm->filp->f_count);
726         return fd;
727 }
728
729 /*
730  * Creates some virtual cpus.  Good luck creating more than one.
731  */
732 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
733 {
734         int r;
735         struct kvm_vcpu *vcpu;
736
737         if (!valid_vcpu(n))
738                 return -EINVAL;
739
740         vcpu = kvm_arch_vcpu_create(kvm, n);
741         if (IS_ERR(vcpu))
742                 return PTR_ERR(vcpu);
743
744         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
745
746         r = kvm_arch_vcpu_setup(vcpu);
747         if (r)
748                 goto vcpu_destroy;
749
750         mutex_lock(&kvm->lock);
751         if (kvm->vcpus[n]) {
752                 r = -EEXIST;
753                 mutex_unlock(&kvm->lock);
754                 goto vcpu_destroy;
755         }
756         kvm->vcpus[n] = vcpu;
757         mutex_unlock(&kvm->lock);
758
759         /* Now it's all set up, let userspace reach it */
760         r = create_vcpu_fd(vcpu);
761         if (r < 0)
762                 goto unlink;
763         return r;
764
765 unlink:
766         mutex_lock(&kvm->lock);
767         kvm->vcpus[n] = NULL;
768         mutex_unlock(&kvm->lock);
769 vcpu_destroy:
770         kvm_arch_vcpu_destroy(vcpu);
771         return r;
772 }
773
774 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
775 {
776         if (sigset) {
777                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
778                 vcpu->sigset_active = 1;
779                 vcpu->sigset = *sigset;
780         } else
781                 vcpu->sigset_active = 0;
782         return 0;
783 }
784
785 static long kvm_vcpu_ioctl(struct file *filp,
786                            unsigned int ioctl, unsigned long arg)
787 {
788         struct kvm_vcpu *vcpu = filp->private_data;
789         void __user *argp = (void __user *)arg;
790         int r;
791
792         if (vcpu->kvm->mm != current->mm)
793                 return -EIO;
794         switch (ioctl) {
795         case KVM_RUN:
796                 r = -EINVAL;
797                 if (arg)
798                         goto out;
799                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
800                 break;
801         case KVM_GET_REGS: {
802                 struct kvm_regs kvm_regs;
803
804                 memset(&kvm_regs, 0, sizeof kvm_regs);
805                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
806                 if (r)
807                         goto out;
808                 r = -EFAULT;
809                 if (copy_to_user(argp, &kvm_regs, sizeof kvm_regs))
810                         goto out;
811                 r = 0;
812                 break;
813         }
814         case KVM_SET_REGS: {
815                 struct kvm_regs kvm_regs;
816
817                 r = -EFAULT;
818                 if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
819                         goto out;
820                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
821                 if (r)
822                         goto out;
823                 r = 0;
824                 break;
825         }
826         case KVM_GET_SREGS: {
827                 struct kvm_sregs kvm_sregs;
828
829                 memset(&kvm_sregs, 0, sizeof kvm_sregs);
830                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
831                 if (r)
832                         goto out;
833                 r = -EFAULT;
834                 if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
835                         goto out;
836                 r = 0;
837                 break;
838         }
839         case KVM_SET_SREGS: {
840                 struct kvm_sregs kvm_sregs;
841
842                 r = -EFAULT;
843                 if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
844                         goto out;
845                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
846                 if (r)
847                         goto out;
848                 r = 0;
849                 break;
850         }
851         case KVM_TRANSLATE: {
852                 struct kvm_translation tr;
853
854                 r = -EFAULT;
855                 if (copy_from_user(&tr, argp, sizeof tr))
856                         goto out;
857                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
858                 if (r)
859                         goto out;
860                 r = -EFAULT;
861                 if (copy_to_user(argp, &tr, sizeof tr))
862                         goto out;
863                 r = 0;
864                 break;
865         }
866         case KVM_DEBUG_GUEST: {
867                 struct kvm_debug_guest dbg;
868
869                 r = -EFAULT;
870                 if (copy_from_user(&dbg, argp, sizeof dbg))
871                         goto out;
872                 r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
873                 if (r)
874                         goto out;
875                 r = 0;
876                 break;
877         }
878         case KVM_SET_SIGNAL_MASK: {
879                 struct kvm_signal_mask __user *sigmask_arg = argp;
880                 struct kvm_signal_mask kvm_sigmask;
881                 sigset_t sigset, *p;
882
883                 p = NULL;
884                 if (argp) {
885                         r = -EFAULT;
886                         if (copy_from_user(&kvm_sigmask, argp,
887                                            sizeof kvm_sigmask))
888                                 goto out;
889                         r = -EINVAL;
890                         if (kvm_sigmask.len != sizeof sigset)
891                                 goto out;
892                         r = -EFAULT;
893                         if (copy_from_user(&sigset, sigmask_arg->sigset,
894                                            sizeof sigset))
895                                 goto out;
896                         p = &sigset;
897                 }
898                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
899                 break;
900         }
901         case KVM_GET_FPU: {
902                 struct kvm_fpu fpu;
903
904                 memset(&fpu, 0, sizeof fpu);
905                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
906                 if (r)
907                         goto out;
908                 r = -EFAULT;
909                 if (copy_to_user(argp, &fpu, sizeof fpu))
910                         goto out;
911                 r = 0;
912                 break;
913         }
914         case KVM_SET_FPU: {
915                 struct kvm_fpu fpu;
916
917                 r = -EFAULT;
918                 if (copy_from_user(&fpu, argp, sizeof fpu))
919                         goto out;
920                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
921                 if (r)
922                         goto out;
923                 r = 0;
924                 break;
925         }
926         default:
927                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
928         }
929 out:
930         return r;
931 }
932
933 static long kvm_vm_ioctl(struct file *filp,
934                            unsigned int ioctl, unsigned long arg)
935 {
936         struct kvm *kvm = filp->private_data;
937         void __user *argp = (void __user *)arg;
938         int r;
939
940         if (kvm->mm != current->mm)
941                 return -EIO;
942         switch (ioctl) {
943         case KVM_CREATE_VCPU:
944                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
945                 if (r < 0)
946                         goto out;
947                 break;
948         case KVM_SET_USER_MEMORY_REGION: {
949                 struct kvm_userspace_memory_region kvm_userspace_mem;
950
951                 r = -EFAULT;
952                 if (copy_from_user(&kvm_userspace_mem, argp,
953                                                 sizeof kvm_userspace_mem))
954                         goto out;
955
956                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
957                 if (r)
958                         goto out;
959                 break;
960         }
961         case KVM_GET_DIRTY_LOG: {
962                 struct kvm_dirty_log log;
963
964                 r = -EFAULT;
965                 if (copy_from_user(&log, argp, sizeof log))
966                         goto out;
967                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
968                 if (r)
969                         goto out;
970                 break;
971         }
972         default:
973                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
974         }
975 out:
976         return r;
977 }
978
979 static struct page *kvm_vm_nopage(struct vm_area_struct *vma,
980                                   unsigned long address,
981                                   int *type)
982 {
983         struct kvm *kvm = vma->vm_file->private_data;
984         unsigned long pgoff;
985         struct page *page;
986
987         pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
988         if (!kvm_is_visible_gfn(kvm, pgoff))
989                 return NOPAGE_SIGBUS;
990         /* current->mm->mmap_sem is already held so call lockless version */
991         page = __gfn_to_page(kvm, pgoff);
992         if (is_error_page(page)) {
993                 kvm_release_page_clean(page);
994                 return NOPAGE_SIGBUS;
995         }
996         if (type != NULL)
997                 *type = VM_FAULT_MINOR;
998
999         return page;
1000 }
1001
1002 static struct vm_operations_struct kvm_vm_vm_ops = {
1003         .nopage = kvm_vm_nopage,
1004 };
1005
1006 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1007 {
1008         vma->vm_ops = &kvm_vm_vm_ops;
1009         return 0;
1010 }
1011
1012 static struct file_operations kvm_vm_fops = {
1013         .release        = kvm_vm_release,
1014         .unlocked_ioctl = kvm_vm_ioctl,
1015         .compat_ioctl   = kvm_vm_ioctl,
1016         .mmap           = kvm_vm_mmap,
1017 };
1018
1019 static int kvm_dev_ioctl_create_vm(void)
1020 {
1021         int fd, r;
1022         struct inode *inode;
1023         struct file *file;
1024         struct kvm *kvm;
1025
1026         kvm = kvm_create_vm();
1027         if (IS_ERR(kvm))
1028                 return PTR_ERR(kvm);
1029         r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
1030         if (r) {
1031                 kvm_destroy_vm(kvm);
1032                 return r;
1033         }
1034
1035         kvm->filp = file;
1036
1037         return fd;
1038 }
1039
1040 static long kvm_dev_ioctl(struct file *filp,
1041                           unsigned int ioctl, unsigned long arg)
1042 {
1043         void __user *argp = (void __user *)arg;
1044         long r = -EINVAL;
1045
1046         switch (ioctl) {
1047         case KVM_GET_API_VERSION:
1048                 r = -EINVAL;
1049                 if (arg)
1050                         goto out;
1051                 r = KVM_API_VERSION;
1052                 break;
1053         case KVM_CREATE_VM:
1054                 r = -EINVAL;
1055                 if (arg)
1056                         goto out;
1057                 r = kvm_dev_ioctl_create_vm();
1058                 break;
1059         case KVM_CHECK_EXTENSION:
1060                 r = kvm_dev_ioctl_check_extension((long)argp);
1061                 break;
1062         case KVM_GET_VCPU_MMAP_SIZE:
1063                 r = -EINVAL;
1064                 if (arg)
1065                         goto out;
1066                 r = 2 * PAGE_SIZE;
1067                 break;
1068         default:
1069                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
1070         }
1071 out:
1072         return r;
1073 }
1074
1075 static struct file_operations kvm_chardev_ops = {
1076         .unlocked_ioctl = kvm_dev_ioctl,
1077         .compat_ioctl   = kvm_dev_ioctl,
1078 };
1079
1080 static struct miscdevice kvm_dev = {
1081         KVM_MINOR,
1082         "kvm",
1083         &kvm_chardev_ops,
1084 };
1085
1086 static void hardware_enable(void *junk)
1087 {
1088         int cpu = raw_smp_processor_id();
1089
1090         if (cpu_isset(cpu, cpus_hardware_enabled))
1091                 return;
1092         cpu_set(cpu, cpus_hardware_enabled);
1093         kvm_arch_hardware_enable(NULL);
1094 }
1095
1096 static void hardware_disable(void *junk)
1097 {
1098         int cpu = raw_smp_processor_id();
1099
1100         if (!cpu_isset(cpu, cpus_hardware_enabled))
1101                 return;
1102         cpu_clear(cpu, cpus_hardware_enabled);
1103         decache_vcpus_on_cpu(cpu);
1104         kvm_arch_hardware_disable(NULL);
1105 }
1106
1107 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1108                            void *v)
1109 {
1110         int cpu = (long)v;
1111
1112         val &= ~CPU_TASKS_FROZEN;
1113         switch (val) {
1114         case CPU_DYING:
1115                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1116                        cpu);
1117                 hardware_disable(NULL);
1118                 break;
1119         case CPU_UP_CANCELED:
1120                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1121                        cpu);
1122                 smp_call_function_single(cpu, hardware_disable, NULL, 0, 1);
1123                 break;
1124         case CPU_ONLINE:
1125                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1126                        cpu);
1127                 smp_call_function_single(cpu, hardware_enable, NULL, 0, 1);
1128                 break;
1129         }
1130         return NOTIFY_OK;
1131 }
1132
1133 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1134                       void *v)
1135 {
1136         if (val == SYS_RESTART) {
1137                 /*
1138                  * Some (well, at least mine) BIOSes hang on reboot if
1139                  * in vmx root mode.
1140                  */
1141                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1142                 on_each_cpu(hardware_disable, NULL, 0, 1);
1143         }
1144         return NOTIFY_OK;
1145 }
1146
1147 static struct notifier_block kvm_reboot_notifier = {
1148         .notifier_call = kvm_reboot,
1149         .priority = 0,
1150 };
1151
1152 void kvm_io_bus_init(struct kvm_io_bus *bus)
1153 {
1154         memset(bus, 0, sizeof(*bus));
1155 }
1156
1157 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1158 {
1159         int i;
1160
1161         for (i = 0; i < bus->dev_count; i++) {
1162                 struct kvm_io_device *pos = bus->devs[i];
1163
1164                 kvm_iodevice_destructor(pos);
1165         }
1166 }
1167
1168 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr)
1169 {
1170         int i;
1171
1172         for (i = 0; i < bus->dev_count; i++) {
1173                 struct kvm_io_device *pos = bus->devs[i];
1174
1175                 if (pos->in_range(pos, addr))
1176                         return pos;
1177         }
1178
1179         return NULL;
1180 }
1181
1182 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1183 {
1184         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1185
1186         bus->devs[bus->dev_count++] = dev;
1187 }
1188
1189 static struct notifier_block kvm_cpu_notifier = {
1190         .notifier_call = kvm_cpu_hotplug,
1191         .priority = 20, /* must be > scheduler priority */
1192 };
1193
1194 static u64 vm_stat_get(void *_offset)
1195 {
1196         unsigned offset = (long)_offset;
1197         u64 total = 0;
1198         struct kvm *kvm;
1199
1200         spin_lock(&kvm_lock);
1201         list_for_each_entry(kvm, &vm_list, vm_list)
1202                 total += *(u32 *)((void *)kvm + offset);
1203         spin_unlock(&kvm_lock);
1204         return total;
1205 }
1206
1207 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1208
1209 static u64 vcpu_stat_get(void *_offset)
1210 {
1211         unsigned offset = (long)_offset;
1212         u64 total = 0;
1213         struct kvm *kvm;
1214         struct kvm_vcpu *vcpu;
1215         int i;
1216
1217         spin_lock(&kvm_lock);
1218         list_for_each_entry(kvm, &vm_list, vm_list)
1219                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1220                         vcpu = kvm->vcpus[i];
1221                         if (vcpu)
1222                                 total += *(u32 *)((void *)vcpu + offset);
1223                 }
1224         spin_unlock(&kvm_lock);
1225         return total;
1226 }
1227
1228 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1229
1230 static struct file_operations *stat_fops[] = {
1231         [KVM_STAT_VCPU] = &vcpu_stat_fops,
1232         [KVM_STAT_VM]   = &vm_stat_fops,
1233 };
1234
1235 static void kvm_init_debug(void)
1236 {
1237         struct kvm_stats_debugfs_item *p;
1238
1239         debugfs_dir = debugfs_create_dir("kvm", NULL);
1240         for (p = debugfs_entries; p->name; ++p)
1241                 p->dentry = debugfs_create_file(p->name, 0444, debugfs_dir,
1242                                                 (void *)(long)p->offset,
1243                                                 stat_fops[p->kind]);
1244 }
1245
1246 static void kvm_exit_debug(void)
1247 {
1248         struct kvm_stats_debugfs_item *p;
1249
1250         for (p = debugfs_entries; p->name; ++p)
1251                 debugfs_remove(p->dentry);
1252         debugfs_remove(debugfs_dir);
1253 }
1254
1255 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1256 {
1257         hardware_disable(NULL);
1258         return 0;
1259 }
1260
1261 static int kvm_resume(struct sys_device *dev)
1262 {
1263         hardware_enable(NULL);
1264         return 0;
1265 }
1266
1267 static struct sysdev_class kvm_sysdev_class = {
1268         .name = "kvm",
1269         .suspend = kvm_suspend,
1270         .resume = kvm_resume,
1271 };
1272
1273 static struct sys_device kvm_sysdev = {
1274         .id = 0,
1275         .cls = &kvm_sysdev_class,
1276 };
1277
1278 struct page *bad_page;
1279
1280 static inline
1281 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1282 {
1283         return container_of(pn, struct kvm_vcpu, preempt_notifier);
1284 }
1285
1286 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1287 {
1288         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1289
1290         kvm_arch_vcpu_load(vcpu, cpu);
1291 }
1292
1293 static void kvm_sched_out(struct preempt_notifier *pn,
1294                           struct task_struct *next)
1295 {
1296         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1297
1298         kvm_arch_vcpu_put(vcpu);
1299 }
1300
1301 int kvm_init(void *opaque, unsigned int vcpu_size,
1302                   struct module *module)
1303 {
1304         int r;
1305         int cpu;
1306
1307         kvm_init_debug();
1308
1309         r = kvm_arch_init(opaque);
1310         if (r)
1311                 goto out_fail;
1312
1313         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1314
1315         if (bad_page == NULL) {
1316                 r = -ENOMEM;
1317                 goto out;
1318         }
1319
1320         r = kvm_arch_hardware_setup();
1321         if (r < 0)
1322                 goto out_free_0;
1323
1324         for_each_online_cpu(cpu) {
1325                 smp_call_function_single(cpu,
1326                                 kvm_arch_check_processor_compat,
1327                                 &r, 0, 1);
1328                 if (r < 0)
1329                         goto out_free_1;
1330         }
1331
1332         on_each_cpu(hardware_enable, NULL, 0, 1);
1333         r = register_cpu_notifier(&kvm_cpu_notifier);
1334         if (r)
1335                 goto out_free_2;
1336         register_reboot_notifier(&kvm_reboot_notifier);
1337
1338         r = sysdev_class_register(&kvm_sysdev_class);
1339         if (r)
1340                 goto out_free_3;
1341
1342         r = sysdev_register(&kvm_sysdev);
1343         if (r)
1344                 goto out_free_4;
1345
1346         /* A kmem cache lets us meet the alignment requirements of fx_save. */
1347         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
1348                                            __alignof__(struct kvm_vcpu),
1349                                            0, NULL);
1350         if (!kvm_vcpu_cache) {
1351                 r = -ENOMEM;
1352                 goto out_free_5;
1353         }
1354
1355         kvm_chardev_ops.owner = module;
1356
1357         r = misc_register(&kvm_dev);
1358         if (r) {
1359                 printk(KERN_ERR "kvm: misc device register failed\n");
1360                 goto out_free;
1361         }
1362
1363         kvm_preempt_ops.sched_in = kvm_sched_in;
1364         kvm_preempt_ops.sched_out = kvm_sched_out;
1365
1366         return 0;
1367
1368 out_free:
1369         kmem_cache_destroy(kvm_vcpu_cache);
1370 out_free_5:
1371         sysdev_unregister(&kvm_sysdev);
1372 out_free_4:
1373         sysdev_class_unregister(&kvm_sysdev_class);
1374 out_free_3:
1375         unregister_reboot_notifier(&kvm_reboot_notifier);
1376         unregister_cpu_notifier(&kvm_cpu_notifier);
1377 out_free_2:
1378         on_each_cpu(hardware_disable, NULL, 0, 1);
1379 out_free_1:
1380         kvm_arch_hardware_unsetup();
1381 out_free_0:
1382         __free_page(bad_page);
1383 out:
1384         kvm_arch_exit();
1385         kvm_exit_debug();
1386 out_fail:
1387         return r;
1388 }
1389 EXPORT_SYMBOL_GPL(kvm_init);
1390
1391 void kvm_exit(void)
1392 {
1393         misc_deregister(&kvm_dev);
1394         kmem_cache_destroy(kvm_vcpu_cache);
1395         sysdev_unregister(&kvm_sysdev);
1396         sysdev_class_unregister(&kvm_sysdev_class);
1397         unregister_reboot_notifier(&kvm_reboot_notifier);
1398         unregister_cpu_notifier(&kvm_cpu_notifier);
1399         on_each_cpu(hardware_disable, NULL, 0, 1);
1400         kvm_arch_hardware_unsetup();
1401         kvm_arch_exit();
1402         kvm_exit_debug();
1403         __free_page(bad_page);
1404 }
1405 EXPORT_SYMBOL_GPL(kvm_exit);