Pull trivial into release branch
[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
20 #include <linux/kvm.h>
21 #include <linux/module.h>
22 #include <linux/errno.h>
23 #include <asm/processor.h>
24 #include <linux/percpu.h>
25 #include <linux/gfp.h>
26 #include <asm/msr.h>
27 #include <linux/mm.h>
28 #include <linux/miscdevice.h>
29 #include <linux/vmalloc.h>
30 #include <asm/uaccess.h>
31 #include <linux/reboot.h>
32 #include <asm/io.h>
33 #include <linux/debugfs.h>
34 #include <linux/highmem.h>
35 #include <linux/file.h>
36 #include <asm/desc.h>
37
38 #include "x86_emulate.h"
39 #include "segment_descriptor.h"
40
41 MODULE_AUTHOR("Qumranet");
42 MODULE_LICENSE("GPL");
43
44 struct kvm_arch_ops *kvm_arch_ops;
45 struct kvm_stat kvm_stat;
46 EXPORT_SYMBOL_GPL(kvm_stat);
47
48 static struct kvm_stats_debugfs_item {
49         const char *name;
50         u32 *data;
51         struct dentry *dentry;
52 } debugfs_entries[] = {
53         { "pf_fixed", &kvm_stat.pf_fixed },
54         { "pf_guest", &kvm_stat.pf_guest },
55         { "tlb_flush", &kvm_stat.tlb_flush },
56         { "invlpg", &kvm_stat.invlpg },
57         { "exits", &kvm_stat.exits },
58         { "io_exits", &kvm_stat.io_exits },
59         { "mmio_exits", &kvm_stat.mmio_exits },
60         { "signal_exits", &kvm_stat.signal_exits },
61         { "irq_window", &kvm_stat.irq_window_exits },
62         { "halt_exits", &kvm_stat.halt_exits },
63         { "request_irq", &kvm_stat.request_irq_exits },
64         { "irq_exits", &kvm_stat.irq_exits },
65         { 0, 0 }
66 };
67
68 static struct dentry *debugfs_dir;
69
70 #define MAX_IO_MSRS 256
71
72 #define CR0_RESEVED_BITS 0xffffffff1ffaffc0ULL
73 #define LMSW_GUEST_MASK 0x0eULL
74 #define CR4_RESEVED_BITS (~((1ULL << 11) - 1))
75 #define CR8_RESEVED_BITS (~0x0fULL)
76 #define EFER_RESERVED_BITS 0xfffffffffffff2fe
77
78 #ifdef CONFIG_X86_64
79 // LDT or TSS descriptor in the GDT. 16 bytes.
80 struct segment_descriptor_64 {
81         struct segment_descriptor s;
82         u32 base_higher;
83         u32 pad_zero;
84 };
85
86 #endif
87
88 unsigned long segment_base(u16 selector)
89 {
90         struct descriptor_table gdt;
91         struct segment_descriptor *d;
92         unsigned long table_base;
93         typedef unsigned long ul;
94         unsigned long v;
95
96         if (selector == 0)
97                 return 0;
98
99         asm ("sgdt %0" : "=m"(gdt));
100         table_base = gdt.base;
101
102         if (selector & 4) {           /* from ldt */
103                 u16 ldt_selector;
104
105                 asm ("sldt %0" : "=g"(ldt_selector));
106                 table_base = segment_base(ldt_selector);
107         }
108         d = (struct segment_descriptor *)(table_base + (selector & ~7));
109         v = d->base_low | ((ul)d->base_mid << 16) | ((ul)d->base_high << 24);
110 #ifdef CONFIG_X86_64
111         if (d->system == 0
112             && (d->type == 2 || d->type == 9 || d->type == 11))
113                 v |= ((ul)((struct segment_descriptor_64 *)d)->base_higher) << 32;
114 #endif
115         return v;
116 }
117 EXPORT_SYMBOL_GPL(segment_base);
118
119 static inline int valid_vcpu(int n)
120 {
121         return likely(n >= 0 && n < KVM_MAX_VCPUS);
122 }
123
124 int kvm_read_guest(struct kvm_vcpu *vcpu,
125                              gva_t addr,
126                              unsigned long size,
127                              void *dest)
128 {
129         unsigned char *host_buf = dest;
130         unsigned long req_size = size;
131
132         while (size) {
133                 hpa_t paddr;
134                 unsigned now;
135                 unsigned offset;
136                 hva_t guest_buf;
137
138                 paddr = gva_to_hpa(vcpu, addr);
139
140                 if (is_error_hpa(paddr))
141                         break;
142
143                 guest_buf = (hva_t)kmap_atomic(
144                                         pfn_to_page(paddr >> PAGE_SHIFT),
145                                         KM_USER0);
146                 offset = addr & ~PAGE_MASK;
147                 guest_buf |= offset;
148                 now = min(size, PAGE_SIZE - offset);
149                 memcpy(host_buf, (void*)guest_buf, now);
150                 host_buf += now;
151                 addr += now;
152                 size -= now;
153                 kunmap_atomic((void *)(guest_buf & PAGE_MASK), KM_USER0);
154         }
155         return req_size - size;
156 }
157 EXPORT_SYMBOL_GPL(kvm_read_guest);
158
159 int kvm_write_guest(struct kvm_vcpu *vcpu,
160                              gva_t addr,
161                              unsigned long size,
162                              void *data)
163 {
164         unsigned char *host_buf = data;
165         unsigned long req_size = size;
166
167         while (size) {
168                 hpa_t paddr;
169                 unsigned now;
170                 unsigned offset;
171                 hva_t guest_buf;
172
173                 paddr = gva_to_hpa(vcpu, addr);
174
175                 if (is_error_hpa(paddr))
176                         break;
177
178                 guest_buf = (hva_t)kmap_atomic(
179                                 pfn_to_page(paddr >> PAGE_SHIFT), KM_USER0);
180                 offset = addr & ~PAGE_MASK;
181                 guest_buf |= offset;
182                 now = min(size, PAGE_SIZE - offset);
183                 memcpy((void*)guest_buf, host_buf, now);
184                 host_buf += now;
185                 addr += now;
186                 size -= now;
187                 kunmap_atomic((void *)(guest_buf & PAGE_MASK), KM_USER0);
188         }
189         return req_size - size;
190 }
191 EXPORT_SYMBOL_GPL(kvm_write_guest);
192
193 static int vcpu_slot(struct kvm_vcpu *vcpu)
194 {
195         return vcpu - vcpu->kvm->vcpus;
196 }
197
198 /*
199  * Switches to specified vcpu, until a matching vcpu_put()
200  */
201 static struct kvm_vcpu *vcpu_load(struct kvm *kvm, int vcpu_slot)
202 {
203         struct kvm_vcpu *vcpu = &kvm->vcpus[vcpu_slot];
204
205         mutex_lock(&vcpu->mutex);
206         if (unlikely(!vcpu->vmcs)) {
207                 mutex_unlock(&vcpu->mutex);
208                 return 0;
209         }
210         return kvm_arch_ops->vcpu_load(vcpu);
211 }
212
213 static void vcpu_put(struct kvm_vcpu *vcpu)
214 {
215         kvm_arch_ops->vcpu_put(vcpu);
216         mutex_unlock(&vcpu->mutex);
217 }
218
219 static int kvm_dev_open(struct inode *inode, struct file *filp)
220 {
221         struct kvm *kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
222         int i;
223
224         if (!kvm)
225                 return -ENOMEM;
226
227         spin_lock_init(&kvm->lock);
228         INIT_LIST_HEAD(&kvm->active_mmu_pages);
229         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
230                 struct kvm_vcpu *vcpu = &kvm->vcpus[i];
231
232                 mutex_init(&vcpu->mutex);
233                 vcpu->kvm = kvm;
234                 vcpu->mmu.root_hpa = INVALID_PAGE;
235                 INIT_LIST_HEAD(&vcpu->free_pages);
236         }
237         filp->private_data = kvm;
238         return 0;
239 }
240
241 /*
242  * Free any memory in @free but not in @dont.
243  */
244 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
245                                   struct kvm_memory_slot *dont)
246 {
247         int i;
248
249         if (!dont || free->phys_mem != dont->phys_mem)
250                 if (free->phys_mem) {
251                         for (i = 0; i < free->npages; ++i)
252                                 if (free->phys_mem[i])
253                                         __free_page(free->phys_mem[i]);
254                         vfree(free->phys_mem);
255                 }
256
257         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
258                 vfree(free->dirty_bitmap);
259
260         free->phys_mem = 0;
261         free->npages = 0;
262         free->dirty_bitmap = 0;
263 }
264
265 static void kvm_free_physmem(struct kvm *kvm)
266 {
267         int i;
268
269         for (i = 0; i < kvm->nmemslots; ++i)
270                 kvm_free_physmem_slot(&kvm->memslots[i], 0);
271 }
272
273 static void kvm_free_vcpu(struct kvm_vcpu *vcpu)
274 {
275         kvm_mmu_destroy(vcpu);
276         kvm_arch_ops->vcpu_free(vcpu);
277 }
278
279 static void kvm_free_vcpus(struct kvm *kvm)
280 {
281         unsigned int i;
282
283         for (i = 0; i < KVM_MAX_VCPUS; ++i)
284                 kvm_free_vcpu(&kvm->vcpus[i]);
285 }
286
287 static int kvm_dev_release(struct inode *inode, struct file *filp)
288 {
289         struct kvm *kvm = filp->private_data;
290
291         kvm_free_vcpus(kvm);
292         kvm_free_physmem(kvm);
293         kfree(kvm);
294         return 0;
295 }
296
297 static void inject_gp(struct kvm_vcpu *vcpu)
298 {
299         kvm_arch_ops->inject_gp(vcpu, 0);
300 }
301
302 /*
303  * Load the pae pdptrs.  Return true is they are all valid.
304  */
305 static int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3)
306 {
307         gfn_t pdpt_gfn = cr3 >> PAGE_SHIFT;
308         unsigned offset = ((cr3 & (PAGE_SIZE-1)) >> 5) << 2;
309         int i;
310         u64 pdpte;
311         u64 *pdpt;
312         int ret;
313         struct kvm_memory_slot *memslot;
314
315         spin_lock(&vcpu->kvm->lock);
316         memslot = gfn_to_memslot(vcpu->kvm, pdpt_gfn);
317         /* FIXME: !memslot - emulate? 0xff? */
318         pdpt = kmap_atomic(gfn_to_page(memslot, pdpt_gfn), KM_USER0);
319
320         ret = 1;
321         for (i = 0; i < 4; ++i) {
322                 pdpte = pdpt[offset + i];
323                 if ((pdpte & 1) && (pdpte & 0xfffffff0000001e6ull)) {
324                         ret = 0;
325                         goto out;
326                 }
327         }
328
329         for (i = 0; i < 4; ++i)
330                 vcpu->pdptrs[i] = pdpt[offset + i];
331
332 out:
333         kunmap_atomic(pdpt, KM_USER0);
334         spin_unlock(&vcpu->kvm->lock);
335
336         return ret;
337 }
338
339 void set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
340 {
341         if (cr0 & CR0_RESEVED_BITS) {
342                 printk(KERN_DEBUG "set_cr0: 0x%lx #GP, reserved bits 0x%lx\n",
343                        cr0, vcpu->cr0);
344                 inject_gp(vcpu);
345                 return;
346         }
347
348         if ((cr0 & CR0_NW_MASK) && !(cr0 & CR0_CD_MASK)) {
349                 printk(KERN_DEBUG "set_cr0: #GP, CD == 0 && NW == 1\n");
350                 inject_gp(vcpu);
351                 return;
352         }
353
354         if ((cr0 & CR0_PG_MASK) && !(cr0 & CR0_PE_MASK)) {
355                 printk(KERN_DEBUG "set_cr0: #GP, set PG flag "
356                        "and a clear PE flag\n");
357                 inject_gp(vcpu);
358                 return;
359         }
360
361         if (!is_paging(vcpu) && (cr0 & CR0_PG_MASK)) {
362 #ifdef CONFIG_X86_64
363                 if ((vcpu->shadow_efer & EFER_LME)) {
364                         int cs_db, cs_l;
365
366                         if (!is_pae(vcpu)) {
367                                 printk(KERN_DEBUG "set_cr0: #GP, start paging "
368                                        "in long mode while PAE is disabled\n");
369                                 inject_gp(vcpu);
370                                 return;
371                         }
372                         kvm_arch_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
373                         if (cs_l) {
374                                 printk(KERN_DEBUG "set_cr0: #GP, start paging "
375                                        "in long mode while CS.L == 1\n");
376                                 inject_gp(vcpu);
377                                 return;
378
379                         }
380                 } else
381 #endif
382                 if (is_pae(vcpu) && !load_pdptrs(vcpu, vcpu->cr3)) {
383                         printk(KERN_DEBUG "set_cr0: #GP, pdptrs "
384                                "reserved bits\n");
385                         inject_gp(vcpu);
386                         return;
387                 }
388
389         }
390
391         kvm_arch_ops->set_cr0(vcpu, cr0);
392         vcpu->cr0 = cr0;
393
394         spin_lock(&vcpu->kvm->lock);
395         kvm_mmu_reset_context(vcpu);
396         spin_unlock(&vcpu->kvm->lock);
397         return;
398 }
399 EXPORT_SYMBOL_GPL(set_cr0);
400
401 void lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
402 {
403         kvm_arch_ops->decache_cr0_cr4_guest_bits(vcpu);
404         set_cr0(vcpu, (vcpu->cr0 & ~0x0ful) | (msw & 0x0f));
405 }
406 EXPORT_SYMBOL_GPL(lmsw);
407
408 void set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
409 {
410         if (cr4 & CR4_RESEVED_BITS) {
411                 printk(KERN_DEBUG "set_cr4: #GP, reserved bits\n");
412                 inject_gp(vcpu);
413                 return;
414         }
415
416         if (is_long_mode(vcpu)) {
417                 if (!(cr4 & CR4_PAE_MASK)) {
418                         printk(KERN_DEBUG "set_cr4: #GP, clearing PAE while "
419                                "in long mode\n");
420                         inject_gp(vcpu);
421                         return;
422                 }
423         } else if (is_paging(vcpu) && !is_pae(vcpu) && (cr4 & CR4_PAE_MASK)
424                    && !load_pdptrs(vcpu, vcpu->cr3)) {
425                 printk(KERN_DEBUG "set_cr4: #GP, pdptrs reserved bits\n");
426                 inject_gp(vcpu);
427         }
428
429         if (cr4 & CR4_VMXE_MASK) {
430                 printk(KERN_DEBUG "set_cr4: #GP, setting VMXE\n");
431                 inject_gp(vcpu);
432                 return;
433         }
434         kvm_arch_ops->set_cr4(vcpu, cr4);
435         spin_lock(&vcpu->kvm->lock);
436         kvm_mmu_reset_context(vcpu);
437         spin_unlock(&vcpu->kvm->lock);
438 }
439 EXPORT_SYMBOL_GPL(set_cr4);
440
441 void set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
442 {
443         if (is_long_mode(vcpu)) {
444                 if ( cr3 & CR3_L_MODE_RESEVED_BITS) {
445                         printk(KERN_DEBUG "set_cr3: #GP, reserved bits\n");
446                         inject_gp(vcpu);
447                         return;
448                 }
449         } else {
450                 if (cr3 & CR3_RESEVED_BITS) {
451                         printk(KERN_DEBUG "set_cr3: #GP, reserved bits\n");
452                         inject_gp(vcpu);
453                         return;
454                 }
455                 if (is_paging(vcpu) && is_pae(vcpu) &&
456                     !load_pdptrs(vcpu, cr3)) {
457                         printk(KERN_DEBUG "set_cr3: #GP, pdptrs "
458                                "reserved bits\n");
459                         inject_gp(vcpu);
460                         return;
461                 }
462         }
463
464         vcpu->cr3 = cr3;
465         spin_lock(&vcpu->kvm->lock);
466         /*
467          * Does the new cr3 value map to physical memory? (Note, we
468          * catch an invalid cr3 even in real-mode, because it would
469          * cause trouble later on when we turn on paging anyway.)
470          *
471          * A real CPU would silently accept an invalid cr3 and would
472          * attempt to use it - with largely undefined (and often hard
473          * to debug) behavior on the guest side.
474          */
475         if (unlikely(!gfn_to_memslot(vcpu->kvm, cr3 >> PAGE_SHIFT)))
476                 inject_gp(vcpu);
477         else
478                 vcpu->mmu.new_cr3(vcpu);
479         spin_unlock(&vcpu->kvm->lock);
480 }
481 EXPORT_SYMBOL_GPL(set_cr3);
482
483 void set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8)
484 {
485         if ( cr8 & CR8_RESEVED_BITS) {
486                 printk(KERN_DEBUG "set_cr8: #GP, reserved bits 0x%lx\n", cr8);
487                 inject_gp(vcpu);
488                 return;
489         }
490         vcpu->cr8 = cr8;
491 }
492 EXPORT_SYMBOL_GPL(set_cr8);
493
494 void fx_init(struct kvm_vcpu *vcpu)
495 {
496         struct __attribute__ ((__packed__)) fx_image_s {
497                 u16 control; //fcw
498                 u16 status; //fsw
499                 u16 tag; // ftw
500                 u16 opcode; //fop
501                 u64 ip; // fpu ip
502                 u64 operand;// fpu dp
503                 u32 mxcsr;
504                 u32 mxcsr_mask;
505
506         } *fx_image;
507
508         fx_save(vcpu->host_fx_image);
509         fpu_init();
510         fx_save(vcpu->guest_fx_image);
511         fx_restore(vcpu->host_fx_image);
512
513         fx_image = (struct fx_image_s *)vcpu->guest_fx_image;
514         fx_image->mxcsr = 0x1f80;
515         memset(vcpu->guest_fx_image + sizeof(struct fx_image_s),
516                0, FX_IMAGE_SIZE - sizeof(struct fx_image_s));
517 }
518 EXPORT_SYMBOL_GPL(fx_init);
519
520 /*
521  * Creates some virtual cpus.  Good luck creating more than one.
522  */
523 static int kvm_dev_ioctl_create_vcpu(struct kvm *kvm, int n)
524 {
525         int r;
526         struct kvm_vcpu *vcpu;
527
528         r = -EINVAL;
529         if (!valid_vcpu(n))
530                 goto out;
531
532         vcpu = &kvm->vcpus[n];
533
534         mutex_lock(&vcpu->mutex);
535
536         if (vcpu->vmcs) {
537                 mutex_unlock(&vcpu->mutex);
538                 return -EEXIST;
539         }
540
541         vcpu->host_fx_image = (char*)ALIGN((hva_t)vcpu->fx_buf,
542                                            FX_IMAGE_ALIGN);
543         vcpu->guest_fx_image = vcpu->host_fx_image + FX_IMAGE_SIZE;
544
545         vcpu->cpu = -1;  /* First load will set up TR */
546         r = kvm_arch_ops->vcpu_create(vcpu);
547         if (r < 0)
548                 goto out_free_vcpus;
549
550         r = kvm_mmu_create(vcpu);
551         if (r < 0)
552                 goto out_free_vcpus;
553
554         kvm_arch_ops->vcpu_load(vcpu);
555         r = kvm_mmu_setup(vcpu);
556         if (r >= 0)
557                 r = kvm_arch_ops->vcpu_setup(vcpu);
558         vcpu_put(vcpu);
559
560         if (r < 0)
561                 goto out_free_vcpus;
562
563         return 0;
564
565 out_free_vcpus:
566         kvm_free_vcpu(vcpu);
567         mutex_unlock(&vcpu->mutex);
568 out:
569         return r;
570 }
571
572 /*
573  * Allocate some memory and give it an address in the guest physical address
574  * space.
575  *
576  * Discontiguous memory is allowed, mostly for framebuffers.
577  */
578 static int kvm_dev_ioctl_set_memory_region(struct kvm *kvm,
579                                            struct kvm_memory_region *mem)
580 {
581         int r;
582         gfn_t base_gfn;
583         unsigned long npages;
584         unsigned long i;
585         struct kvm_memory_slot *memslot;
586         struct kvm_memory_slot old, new;
587         int memory_config_version;
588
589         r = -EINVAL;
590         /* General sanity checks */
591         if (mem->memory_size & (PAGE_SIZE - 1))
592                 goto out;
593         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
594                 goto out;
595         if (mem->slot >= KVM_MEMORY_SLOTS)
596                 goto out;
597         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
598                 goto out;
599
600         memslot = &kvm->memslots[mem->slot];
601         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
602         npages = mem->memory_size >> PAGE_SHIFT;
603
604         if (!npages)
605                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
606
607 raced:
608         spin_lock(&kvm->lock);
609
610         memory_config_version = kvm->memory_config_version;
611         new = old = *memslot;
612
613         new.base_gfn = base_gfn;
614         new.npages = npages;
615         new.flags = mem->flags;
616
617         /* Disallow changing a memory slot's size. */
618         r = -EINVAL;
619         if (npages && old.npages && npages != old.npages)
620                 goto out_unlock;
621
622         /* Check for overlaps */
623         r = -EEXIST;
624         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
625                 struct kvm_memory_slot *s = &kvm->memslots[i];
626
627                 if (s == memslot)
628                         continue;
629                 if (!((base_gfn + npages <= s->base_gfn) ||
630                       (base_gfn >= s->base_gfn + s->npages)))
631                         goto out_unlock;
632         }
633         /*
634          * Do memory allocations outside lock.  memory_config_version will
635          * detect any races.
636          */
637         spin_unlock(&kvm->lock);
638
639         /* Deallocate if slot is being removed */
640         if (!npages)
641                 new.phys_mem = 0;
642
643         /* Free page dirty bitmap if unneeded */
644         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
645                 new.dirty_bitmap = 0;
646
647         r = -ENOMEM;
648
649         /* Allocate if a slot is being created */
650         if (npages && !new.phys_mem) {
651                 new.phys_mem = vmalloc(npages * sizeof(struct page *));
652
653                 if (!new.phys_mem)
654                         goto out_free;
655
656                 memset(new.phys_mem, 0, npages * sizeof(struct page *));
657                 for (i = 0; i < npages; ++i) {
658                         new.phys_mem[i] = alloc_page(GFP_HIGHUSER
659                                                      | __GFP_ZERO);
660                         if (!new.phys_mem[i])
661                                 goto out_free;
662                         new.phys_mem[i]->private = 0;
663                 }
664         }
665
666         /* Allocate page dirty bitmap if needed */
667         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
668                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
669
670                 new.dirty_bitmap = vmalloc(dirty_bytes);
671                 if (!new.dirty_bitmap)
672                         goto out_free;
673                 memset(new.dirty_bitmap, 0, dirty_bytes);
674         }
675
676         spin_lock(&kvm->lock);
677
678         if (memory_config_version != kvm->memory_config_version) {
679                 spin_unlock(&kvm->lock);
680                 kvm_free_physmem_slot(&new, &old);
681                 goto raced;
682         }
683
684         r = -EAGAIN;
685         if (kvm->busy)
686                 goto out_unlock;
687
688         if (mem->slot >= kvm->nmemslots)
689                 kvm->nmemslots = mem->slot + 1;
690
691         *memslot = new;
692         ++kvm->memory_config_version;
693
694         spin_unlock(&kvm->lock);
695
696         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
697                 struct kvm_vcpu *vcpu;
698
699                 vcpu = vcpu_load(kvm, i);
700                 if (!vcpu)
701                         continue;
702                 kvm_mmu_reset_context(vcpu);
703                 vcpu_put(vcpu);
704         }
705
706         kvm_free_physmem_slot(&old, &new);
707         return 0;
708
709 out_unlock:
710         spin_unlock(&kvm->lock);
711 out_free:
712         kvm_free_physmem_slot(&new, &old);
713 out:
714         return r;
715 }
716
717 static void do_remove_write_access(struct kvm_vcpu *vcpu, int slot)
718 {
719         spin_lock(&vcpu->kvm->lock);
720         kvm_mmu_slot_remove_write_access(vcpu, slot);
721         spin_unlock(&vcpu->kvm->lock);
722 }
723
724 /*
725  * Get (and clear) the dirty memory log for a memory slot.
726  */
727 static int kvm_dev_ioctl_get_dirty_log(struct kvm *kvm,
728                                        struct kvm_dirty_log *log)
729 {
730         struct kvm_memory_slot *memslot;
731         int r, i;
732         int n;
733         int cleared;
734         unsigned long any = 0;
735
736         spin_lock(&kvm->lock);
737
738         /*
739          * Prevent changes to guest memory configuration even while the lock
740          * is not taken.
741          */
742         ++kvm->busy;
743         spin_unlock(&kvm->lock);
744         r = -EINVAL;
745         if (log->slot >= KVM_MEMORY_SLOTS)
746                 goto out;
747
748         memslot = &kvm->memslots[log->slot];
749         r = -ENOENT;
750         if (!memslot->dirty_bitmap)
751                 goto out;
752
753         n = ALIGN(memslot->npages, 8) / 8;
754
755         for (i = 0; !any && i < n; ++i)
756                 any = memslot->dirty_bitmap[i];
757
758         r = -EFAULT;
759         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
760                 goto out;
761
762
763         if (any) {
764                 cleared = 0;
765                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
766                         struct kvm_vcpu *vcpu = vcpu_load(kvm, i);
767
768                         if (!vcpu)
769                                 continue;
770                         if (!cleared) {
771                                 do_remove_write_access(vcpu, log->slot);
772                                 memset(memslot->dirty_bitmap, 0, n);
773                                 cleared = 1;
774                         }
775                         kvm_arch_ops->tlb_flush(vcpu);
776                         vcpu_put(vcpu);
777                 }
778         }
779
780         r = 0;
781
782 out:
783         spin_lock(&kvm->lock);
784         --kvm->busy;
785         spin_unlock(&kvm->lock);
786         return r;
787 }
788
789 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
790 {
791         int i;
792
793         for (i = 0; i < kvm->nmemslots; ++i) {
794                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
795
796                 if (gfn >= memslot->base_gfn
797                     && gfn < memslot->base_gfn + memslot->npages)
798                         return memslot;
799         }
800         return 0;
801 }
802 EXPORT_SYMBOL_GPL(gfn_to_memslot);
803
804 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
805 {
806         int i;
807         struct kvm_memory_slot *memslot = 0;
808         unsigned long rel_gfn;
809
810         for (i = 0; i < kvm->nmemslots; ++i) {
811                 memslot = &kvm->memslots[i];
812
813                 if (gfn >= memslot->base_gfn
814                     && gfn < memslot->base_gfn + memslot->npages) {
815
816                         if (!memslot || !memslot->dirty_bitmap)
817                                 return;
818
819                         rel_gfn = gfn - memslot->base_gfn;
820
821                         /* avoid RMW */
822                         if (!test_bit(rel_gfn, memslot->dirty_bitmap))
823                                 set_bit(rel_gfn, memslot->dirty_bitmap);
824                         return;
825                 }
826         }
827 }
828
829 static int emulator_read_std(unsigned long addr,
830                              unsigned long *val,
831                              unsigned int bytes,
832                              struct x86_emulate_ctxt *ctxt)
833 {
834         struct kvm_vcpu *vcpu = ctxt->vcpu;
835         void *data = val;
836
837         while (bytes) {
838                 gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);
839                 unsigned offset = addr & (PAGE_SIZE-1);
840                 unsigned tocopy = min(bytes, (unsigned)PAGE_SIZE - offset);
841                 unsigned long pfn;
842                 struct kvm_memory_slot *memslot;
843                 void *page;
844
845                 if (gpa == UNMAPPED_GVA)
846                         return X86EMUL_PROPAGATE_FAULT;
847                 pfn = gpa >> PAGE_SHIFT;
848                 memslot = gfn_to_memslot(vcpu->kvm, pfn);
849                 if (!memslot)
850                         return X86EMUL_UNHANDLEABLE;
851                 page = kmap_atomic(gfn_to_page(memslot, pfn), KM_USER0);
852
853                 memcpy(data, page + offset, tocopy);
854
855                 kunmap_atomic(page, KM_USER0);
856
857                 bytes -= tocopy;
858                 data += tocopy;
859                 addr += tocopy;
860         }
861
862         return X86EMUL_CONTINUE;
863 }
864
865 static int emulator_write_std(unsigned long addr,
866                               unsigned long val,
867                               unsigned int bytes,
868                               struct x86_emulate_ctxt *ctxt)
869 {
870         printk(KERN_ERR "emulator_write_std: addr %lx n %d\n",
871                addr, bytes);
872         return X86EMUL_UNHANDLEABLE;
873 }
874
875 static int emulator_read_emulated(unsigned long addr,
876                                   unsigned long *val,
877                                   unsigned int bytes,
878                                   struct x86_emulate_ctxt *ctxt)
879 {
880         struct kvm_vcpu *vcpu = ctxt->vcpu;
881
882         if (vcpu->mmio_read_completed) {
883                 memcpy(val, vcpu->mmio_data, bytes);
884                 vcpu->mmio_read_completed = 0;
885                 return X86EMUL_CONTINUE;
886         } else if (emulator_read_std(addr, val, bytes, ctxt)
887                    == X86EMUL_CONTINUE)
888                 return X86EMUL_CONTINUE;
889         else {
890                 gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);
891                 if (gpa == UNMAPPED_GVA)
892                         return vcpu_printf(vcpu, "not present\n"), X86EMUL_PROPAGATE_FAULT;
893                 vcpu->mmio_needed = 1;
894                 vcpu->mmio_phys_addr = gpa;
895                 vcpu->mmio_size = bytes;
896                 vcpu->mmio_is_write = 0;
897
898                 return X86EMUL_UNHANDLEABLE;
899         }
900 }
901
902 static int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
903                                unsigned long val, int bytes)
904 {
905         struct kvm_memory_slot *m;
906         struct page *page;
907         void *virt;
908
909         if (((gpa + bytes - 1) >> PAGE_SHIFT) != (gpa >> PAGE_SHIFT))
910                 return 0;
911         m = gfn_to_memslot(vcpu->kvm, gpa >> PAGE_SHIFT);
912         if (!m)
913                 return 0;
914         page = gfn_to_page(m, gpa >> PAGE_SHIFT);
915         kvm_mmu_pre_write(vcpu, gpa, bytes);
916         virt = kmap_atomic(page, KM_USER0);
917         memcpy(virt + offset_in_page(gpa), &val, bytes);
918         kunmap_atomic(virt, KM_USER0);
919         kvm_mmu_post_write(vcpu, gpa, bytes);
920         return 1;
921 }
922
923 static int emulator_write_emulated(unsigned long addr,
924                                    unsigned long val,
925                                    unsigned int bytes,
926                                    struct x86_emulate_ctxt *ctxt)
927 {
928         struct kvm_vcpu *vcpu = ctxt->vcpu;
929         gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, addr);
930
931         if (gpa == UNMAPPED_GVA)
932                 return X86EMUL_PROPAGATE_FAULT;
933
934         if (emulator_write_phys(vcpu, gpa, val, bytes))
935                 return X86EMUL_CONTINUE;
936
937         vcpu->mmio_needed = 1;
938         vcpu->mmio_phys_addr = gpa;
939         vcpu->mmio_size = bytes;
940         vcpu->mmio_is_write = 1;
941         memcpy(vcpu->mmio_data, &val, bytes);
942
943         return X86EMUL_CONTINUE;
944 }
945
946 static int emulator_cmpxchg_emulated(unsigned long addr,
947                                      unsigned long old,
948                                      unsigned long new,
949                                      unsigned int bytes,
950                                      struct x86_emulate_ctxt *ctxt)
951 {
952         static int reported;
953
954         if (!reported) {
955                 reported = 1;
956                 printk(KERN_WARNING "kvm: emulating exchange as write\n");
957         }
958         return emulator_write_emulated(addr, new, bytes, ctxt);
959 }
960
961 #ifdef CONFIG_X86_32
962
963 static int emulator_cmpxchg8b_emulated(unsigned long addr,
964                                        unsigned long old_lo,
965                                        unsigned long old_hi,
966                                        unsigned long new_lo,
967                                        unsigned long new_hi,
968                                        struct x86_emulate_ctxt *ctxt)
969 {
970         static int reported;
971         int r;
972
973         if (!reported) {
974                 reported = 1;
975                 printk(KERN_WARNING "kvm: emulating exchange8b as write\n");
976         }
977         r = emulator_write_emulated(addr, new_lo, 4, ctxt);
978         if (r != X86EMUL_CONTINUE)
979                 return r;
980         return emulator_write_emulated(addr+4, new_hi, 4, ctxt);
981 }
982
983 #endif
984
985 static unsigned long get_segment_base(struct kvm_vcpu *vcpu, int seg)
986 {
987         return kvm_arch_ops->get_segment_base(vcpu, seg);
988 }
989
990 int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address)
991 {
992         return X86EMUL_CONTINUE;
993 }
994
995 int emulate_clts(struct kvm_vcpu *vcpu)
996 {
997         unsigned long cr0;
998
999         kvm_arch_ops->decache_cr0_cr4_guest_bits(vcpu);
1000         cr0 = vcpu->cr0 & ~CR0_TS_MASK;
1001         kvm_arch_ops->set_cr0(vcpu, cr0);
1002         return X86EMUL_CONTINUE;
1003 }
1004
1005 int emulator_get_dr(struct x86_emulate_ctxt* ctxt, int dr, unsigned long *dest)
1006 {
1007         struct kvm_vcpu *vcpu = ctxt->vcpu;
1008
1009         switch (dr) {
1010         case 0 ... 3:
1011                 *dest = kvm_arch_ops->get_dr(vcpu, dr);
1012                 return X86EMUL_CONTINUE;
1013         default:
1014                 printk(KERN_DEBUG "%s: unexpected dr %u\n",
1015                        __FUNCTION__, dr);
1016                 return X86EMUL_UNHANDLEABLE;
1017         }
1018 }
1019
1020 int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long value)
1021 {
1022         unsigned long mask = (ctxt->mode == X86EMUL_MODE_PROT64) ? ~0ULL : ~0U;
1023         int exception;
1024
1025         kvm_arch_ops->set_dr(ctxt->vcpu, dr, value & mask, &exception);
1026         if (exception) {
1027                 /* FIXME: better handling */
1028                 return X86EMUL_UNHANDLEABLE;
1029         }
1030         return X86EMUL_CONTINUE;
1031 }
1032
1033 static void report_emulation_failure(struct x86_emulate_ctxt *ctxt)
1034 {
1035         static int reported;
1036         u8 opcodes[4];
1037         unsigned long rip = ctxt->vcpu->rip;
1038         unsigned long rip_linear;
1039
1040         rip_linear = rip + get_segment_base(ctxt->vcpu, VCPU_SREG_CS);
1041
1042         if (reported)
1043                 return;
1044
1045         emulator_read_std(rip_linear, (void *)opcodes, 4, ctxt);
1046
1047         printk(KERN_ERR "emulation failed but !mmio_needed?"
1048                " rip %lx %02x %02x %02x %02x\n",
1049                rip, opcodes[0], opcodes[1], opcodes[2], opcodes[3]);
1050         reported = 1;
1051 }
1052
1053 struct x86_emulate_ops emulate_ops = {
1054         .read_std            = emulator_read_std,
1055         .write_std           = emulator_write_std,
1056         .read_emulated       = emulator_read_emulated,
1057         .write_emulated      = emulator_write_emulated,
1058         .cmpxchg_emulated    = emulator_cmpxchg_emulated,
1059 #ifdef CONFIG_X86_32
1060         .cmpxchg8b_emulated  = emulator_cmpxchg8b_emulated,
1061 #endif
1062 };
1063
1064 int emulate_instruction(struct kvm_vcpu *vcpu,
1065                         struct kvm_run *run,
1066                         unsigned long cr2,
1067                         u16 error_code)
1068 {
1069         struct x86_emulate_ctxt emulate_ctxt;
1070         int r;
1071         int cs_db, cs_l;
1072
1073         kvm_arch_ops->cache_regs(vcpu);
1074
1075         kvm_arch_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
1076
1077         emulate_ctxt.vcpu = vcpu;
1078         emulate_ctxt.eflags = kvm_arch_ops->get_rflags(vcpu);
1079         emulate_ctxt.cr2 = cr2;
1080         emulate_ctxt.mode = (emulate_ctxt.eflags & X86_EFLAGS_VM)
1081                 ? X86EMUL_MODE_REAL : cs_l
1082                 ? X86EMUL_MODE_PROT64 : cs_db
1083                 ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
1084
1085         if (emulate_ctxt.mode == X86EMUL_MODE_PROT64) {
1086                 emulate_ctxt.cs_base = 0;
1087                 emulate_ctxt.ds_base = 0;
1088                 emulate_ctxt.es_base = 0;
1089                 emulate_ctxt.ss_base = 0;
1090         } else {
1091                 emulate_ctxt.cs_base = get_segment_base(vcpu, VCPU_SREG_CS);
1092                 emulate_ctxt.ds_base = get_segment_base(vcpu, VCPU_SREG_DS);
1093                 emulate_ctxt.es_base = get_segment_base(vcpu, VCPU_SREG_ES);
1094                 emulate_ctxt.ss_base = get_segment_base(vcpu, VCPU_SREG_SS);
1095         }
1096
1097         emulate_ctxt.gs_base = get_segment_base(vcpu, VCPU_SREG_GS);
1098         emulate_ctxt.fs_base = get_segment_base(vcpu, VCPU_SREG_FS);
1099
1100         vcpu->mmio_is_write = 0;
1101         r = x86_emulate_memop(&emulate_ctxt, &emulate_ops);
1102
1103         if ((r || vcpu->mmio_is_write) && run) {
1104                 run->mmio.phys_addr = vcpu->mmio_phys_addr;
1105                 memcpy(run->mmio.data, vcpu->mmio_data, 8);
1106                 run->mmio.len = vcpu->mmio_size;
1107                 run->mmio.is_write = vcpu->mmio_is_write;
1108         }
1109
1110         if (r) {
1111                 if (kvm_mmu_unprotect_page_virt(vcpu, cr2))
1112                         return EMULATE_DONE;
1113                 if (!vcpu->mmio_needed) {
1114                         report_emulation_failure(&emulate_ctxt);
1115                         return EMULATE_FAIL;
1116                 }
1117                 return EMULATE_DO_MMIO;
1118         }
1119
1120         kvm_arch_ops->decache_regs(vcpu);
1121         kvm_arch_ops->set_rflags(vcpu, emulate_ctxt.eflags);
1122
1123         if (vcpu->mmio_is_write)
1124                 return EMULATE_DO_MMIO;
1125
1126         return EMULATE_DONE;
1127 }
1128 EXPORT_SYMBOL_GPL(emulate_instruction);
1129
1130 static u64 mk_cr_64(u64 curr_cr, u32 new_val)
1131 {
1132         return (curr_cr & ~((1ULL << 32) - 1)) | new_val;
1133 }
1134
1135 void realmode_lgdt(struct kvm_vcpu *vcpu, u16 limit, unsigned long base)
1136 {
1137         struct descriptor_table dt = { limit, base };
1138
1139         kvm_arch_ops->set_gdt(vcpu, &dt);
1140 }
1141
1142 void realmode_lidt(struct kvm_vcpu *vcpu, u16 limit, unsigned long base)
1143 {
1144         struct descriptor_table dt = { limit, base };
1145
1146         kvm_arch_ops->set_idt(vcpu, &dt);
1147 }
1148
1149 void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
1150                    unsigned long *rflags)
1151 {
1152         lmsw(vcpu, msw);
1153         *rflags = kvm_arch_ops->get_rflags(vcpu);
1154 }
1155
1156 unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)
1157 {
1158         kvm_arch_ops->decache_cr0_cr4_guest_bits(vcpu);
1159         switch (cr) {
1160         case 0:
1161                 return vcpu->cr0;
1162         case 2:
1163                 return vcpu->cr2;
1164         case 3:
1165                 return vcpu->cr3;
1166         case 4:
1167                 return vcpu->cr4;
1168         default:
1169                 vcpu_printf(vcpu, "%s: unexpected cr %u\n", __FUNCTION__, cr);
1170                 return 0;
1171         }
1172 }
1173
1174 void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
1175                      unsigned long *rflags)
1176 {
1177         switch (cr) {
1178         case 0:
1179                 set_cr0(vcpu, mk_cr_64(vcpu->cr0, val));
1180                 *rflags = kvm_arch_ops->get_rflags(vcpu);
1181                 break;
1182         case 2:
1183                 vcpu->cr2 = val;
1184                 break;
1185         case 3:
1186                 set_cr3(vcpu, val);
1187                 break;
1188         case 4:
1189                 set_cr4(vcpu, mk_cr_64(vcpu->cr4, val));
1190                 break;
1191         default:
1192                 vcpu_printf(vcpu, "%s: unexpected cr %u\n", __FUNCTION__, cr);
1193         }
1194 }
1195
1196 int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
1197 {
1198         u64 data;
1199
1200         switch (msr) {
1201         case 0xc0010010: /* SYSCFG */
1202         case 0xc0010015: /* HWCR */
1203         case MSR_IA32_PLATFORM_ID:
1204         case MSR_IA32_P5_MC_ADDR:
1205         case MSR_IA32_P5_MC_TYPE:
1206         case MSR_IA32_MC0_CTL:
1207         case MSR_IA32_MCG_STATUS:
1208         case MSR_IA32_MCG_CAP:
1209         case MSR_IA32_MC0_MISC:
1210         case MSR_IA32_MC0_MISC+4:
1211         case MSR_IA32_MC0_MISC+8:
1212         case MSR_IA32_MC0_MISC+12:
1213         case MSR_IA32_MC0_MISC+16:
1214         case MSR_IA32_UCODE_REV:
1215         case MSR_IA32_PERF_STATUS:
1216                 /* MTRR registers */
1217         case 0xfe:
1218         case 0x200 ... 0x2ff:
1219                 data = 0;
1220                 break;
1221         case 0xcd: /* fsb frequency */
1222                 data = 3;
1223                 break;
1224         case MSR_IA32_APICBASE:
1225                 data = vcpu->apic_base;
1226                 break;
1227 #ifdef CONFIG_X86_64
1228         case MSR_EFER:
1229                 data = vcpu->shadow_efer;
1230                 break;
1231 #endif
1232         default:
1233                 printk(KERN_ERR "kvm: unhandled rdmsr: 0x%x\n", msr);
1234                 return 1;
1235         }
1236         *pdata = data;
1237         return 0;
1238 }
1239 EXPORT_SYMBOL_GPL(kvm_get_msr_common);
1240
1241 /*
1242  * Reads an msr value (of 'msr_index') into 'pdata'.
1243  * Returns 0 on success, non-0 otherwise.
1244  * Assumes vcpu_load() was already called.
1245  */
1246 static int get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata)
1247 {
1248         return kvm_arch_ops->get_msr(vcpu, msr_index, pdata);
1249 }
1250
1251 #ifdef CONFIG_X86_64
1252
1253 static void set_efer(struct kvm_vcpu *vcpu, u64 efer)
1254 {
1255         if (efer & EFER_RESERVED_BITS) {
1256                 printk(KERN_DEBUG "set_efer: 0x%llx #GP, reserved bits\n",
1257                        efer);
1258                 inject_gp(vcpu);
1259                 return;
1260         }
1261
1262         if (is_paging(vcpu)
1263             && (vcpu->shadow_efer & EFER_LME) != (efer & EFER_LME)) {
1264                 printk(KERN_DEBUG "set_efer: #GP, change LME while paging\n");
1265                 inject_gp(vcpu);
1266                 return;
1267         }
1268
1269         kvm_arch_ops->set_efer(vcpu, efer);
1270
1271         efer &= ~EFER_LMA;
1272         efer |= vcpu->shadow_efer & EFER_LMA;
1273
1274         vcpu->shadow_efer = efer;
1275 }
1276
1277 #endif
1278
1279 int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
1280 {
1281         switch (msr) {
1282 #ifdef CONFIG_X86_64
1283         case MSR_EFER:
1284                 set_efer(vcpu, data);
1285                 break;
1286 #endif
1287         case MSR_IA32_MC0_STATUS:
1288                 printk(KERN_WARNING "%s: MSR_IA32_MC0_STATUS 0x%llx, nop\n",
1289                        __FUNCTION__, data);
1290                 break;
1291         case MSR_IA32_UCODE_REV:
1292         case MSR_IA32_UCODE_WRITE:
1293         case 0x200 ... 0x2ff: /* MTRRs */
1294                 break;
1295         case MSR_IA32_APICBASE:
1296                 vcpu->apic_base = data;
1297                 break;
1298         default:
1299                 printk(KERN_ERR "kvm: unhandled wrmsr: 0x%x\n", msr);
1300                 return 1;
1301         }
1302         return 0;
1303 }
1304 EXPORT_SYMBOL_GPL(kvm_set_msr_common);
1305
1306 /*
1307  * Writes msr value into into the appropriate "register".
1308  * Returns 0 on success, non-0 otherwise.
1309  * Assumes vcpu_load() was already called.
1310  */
1311 static int set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data)
1312 {
1313         return kvm_arch_ops->set_msr(vcpu, msr_index, data);
1314 }
1315
1316 void kvm_resched(struct kvm_vcpu *vcpu)
1317 {
1318         vcpu_put(vcpu);
1319         cond_resched();
1320         /* Cannot fail -  no vcpu unplug yet. */
1321         vcpu_load(vcpu->kvm, vcpu_slot(vcpu));
1322 }
1323 EXPORT_SYMBOL_GPL(kvm_resched);
1324
1325 void load_msrs(struct vmx_msr_entry *e, int n)
1326 {
1327         int i;
1328
1329         for (i = 0; i < n; ++i)
1330                 wrmsrl(e[i].index, e[i].data);
1331 }
1332 EXPORT_SYMBOL_GPL(load_msrs);
1333
1334 void save_msrs(struct vmx_msr_entry *e, int n)
1335 {
1336         int i;
1337
1338         for (i = 0; i < n; ++i)
1339                 rdmsrl(e[i].index, e[i].data);
1340 }
1341 EXPORT_SYMBOL_GPL(save_msrs);
1342
1343 static int kvm_dev_ioctl_run(struct kvm *kvm, struct kvm_run *kvm_run)
1344 {
1345         struct kvm_vcpu *vcpu;
1346         int r;
1347
1348         if (!valid_vcpu(kvm_run->vcpu))
1349                 return -EINVAL;
1350
1351         vcpu = vcpu_load(kvm, kvm_run->vcpu);
1352         if (!vcpu)
1353                 return -ENOENT;
1354
1355         if (kvm_run->emulated) {
1356                 kvm_arch_ops->skip_emulated_instruction(vcpu);
1357                 kvm_run->emulated = 0;
1358         }
1359
1360         if (kvm_run->mmio_completed) {
1361                 memcpy(vcpu->mmio_data, kvm_run->mmio.data, 8);
1362                 vcpu->mmio_read_completed = 1;
1363         }
1364
1365         vcpu->mmio_needed = 0;
1366
1367         r = kvm_arch_ops->run(vcpu, kvm_run);
1368
1369         vcpu_put(vcpu);
1370         return r;
1371 }
1372
1373 static int kvm_dev_ioctl_get_regs(struct kvm *kvm, struct kvm_regs *regs)
1374 {
1375         struct kvm_vcpu *vcpu;
1376
1377         if (!valid_vcpu(regs->vcpu))
1378                 return -EINVAL;
1379
1380         vcpu = vcpu_load(kvm, regs->vcpu);
1381         if (!vcpu)
1382                 return -ENOENT;
1383
1384         kvm_arch_ops->cache_regs(vcpu);
1385
1386         regs->rax = vcpu->regs[VCPU_REGS_RAX];
1387         regs->rbx = vcpu->regs[VCPU_REGS_RBX];
1388         regs->rcx = vcpu->regs[VCPU_REGS_RCX];
1389         regs->rdx = vcpu->regs[VCPU_REGS_RDX];
1390         regs->rsi = vcpu->regs[VCPU_REGS_RSI];
1391         regs->rdi = vcpu->regs[VCPU_REGS_RDI];
1392         regs->rsp = vcpu->regs[VCPU_REGS_RSP];
1393         regs->rbp = vcpu->regs[VCPU_REGS_RBP];
1394 #ifdef CONFIG_X86_64
1395         regs->r8 = vcpu->regs[VCPU_REGS_R8];
1396         regs->r9 = vcpu->regs[VCPU_REGS_R9];
1397         regs->r10 = vcpu->regs[VCPU_REGS_R10];
1398         regs->r11 = vcpu->regs[VCPU_REGS_R11];
1399         regs->r12 = vcpu->regs[VCPU_REGS_R12];
1400         regs->r13 = vcpu->regs[VCPU_REGS_R13];
1401         regs->r14 = vcpu->regs[VCPU_REGS_R14];
1402         regs->r15 = vcpu->regs[VCPU_REGS_R15];
1403 #endif
1404
1405         regs->rip = vcpu->rip;
1406         regs->rflags = kvm_arch_ops->get_rflags(vcpu);
1407
1408         /*
1409          * Don't leak debug flags in case they were set for guest debugging
1410          */
1411         if (vcpu->guest_debug.enabled && vcpu->guest_debug.singlestep)
1412                 regs->rflags &= ~(X86_EFLAGS_TF | X86_EFLAGS_RF);
1413
1414         vcpu_put(vcpu);
1415
1416         return 0;
1417 }
1418
1419 static int kvm_dev_ioctl_set_regs(struct kvm *kvm, struct kvm_regs *regs)
1420 {
1421         struct kvm_vcpu *vcpu;
1422
1423         if (!valid_vcpu(regs->vcpu))
1424                 return -EINVAL;
1425
1426         vcpu = vcpu_load(kvm, regs->vcpu);
1427         if (!vcpu)
1428                 return -ENOENT;
1429
1430         vcpu->regs[VCPU_REGS_RAX] = regs->rax;
1431         vcpu->regs[VCPU_REGS_RBX] = regs->rbx;
1432         vcpu->regs[VCPU_REGS_RCX] = regs->rcx;
1433         vcpu->regs[VCPU_REGS_RDX] = regs->rdx;
1434         vcpu->regs[VCPU_REGS_RSI] = regs->rsi;
1435         vcpu->regs[VCPU_REGS_RDI] = regs->rdi;
1436         vcpu->regs[VCPU_REGS_RSP] = regs->rsp;
1437         vcpu->regs[VCPU_REGS_RBP] = regs->rbp;
1438 #ifdef CONFIG_X86_64
1439         vcpu->regs[VCPU_REGS_R8] = regs->r8;
1440         vcpu->regs[VCPU_REGS_R9] = regs->r9;
1441         vcpu->regs[VCPU_REGS_R10] = regs->r10;
1442         vcpu->regs[VCPU_REGS_R11] = regs->r11;
1443         vcpu->regs[VCPU_REGS_R12] = regs->r12;
1444         vcpu->regs[VCPU_REGS_R13] = regs->r13;
1445         vcpu->regs[VCPU_REGS_R14] = regs->r14;
1446         vcpu->regs[VCPU_REGS_R15] = regs->r15;
1447 #endif
1448
1449         vcpu->rip = regs->rip;
1450         kvm_arch_ops->set_rflags(vcpu, regs->rflags);
1451
1452         kvm_arch_ops->decache_regs(vcpu);
1453
1454         vcpu_put(vcpu);
1455
1456         return 0;
1457 }
1458
1459 static void get_segment(struct kvm_vcpu *vcpu,
1460                         struct kvm_segment *var, int seg)
1461 {
1462         return kvm_arch_ops->get_segment(vcpu, var, seg);
1463 }
1464
1465 static int kvm_dev_ioctl_get_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
1466 {
1467         struct kvm_vcpu *vcpu;
1468         struct descriptor_table dt;
1469
1470         if (!valid_vcpu(sregs->vcpu))
1471                 return -EINVAL;
1472         vcpu = vcpu_load(kvm, sregs->vcpu);
1473         if (!vcpu)
1474                 return -ENOENT;
1475
1476         get_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
1477         get_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
1478         get_segment(vcpu, &sregs->es, VCPU_SREG_ES);
1479         get_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
1480         get_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
1481         get_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
1482
1483         get_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
1484         get_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
1485
1486         kvm_arch_ops->get_idt(vcpu, &dt);
1487         sregs->idt.limit = dt.limit;
1488         sregs->idt.base = dt.base;
1489         kvm_arch_ops->get_gdt(vcpu, &dt);
1490         sregs->gdt.limit = dt.limit;
1491         sregs->gdt.base = dt.base;
1492
1493         kvm_arch_ops->decache_cr0_cr4_guest_bits(vcpu);
1494         sregs->cr0 = vcpu->cr0;
1495         sregs->cr2 = vcpu->cr2;
1496         sregs->cr3 = vcpu->cr3;
1497         sregs->cr4 = vcpu->cr4;
1498         sregs->cr8 = vcpu->cr8;
1499         sregs->efer = vcpu->shadow_efer;
1500         sregs->apic_base = vcpu->apic_base;
1501
1502         memcpy(sregs->interrupt_bitmap, vcpu->irq_pending,
1503                sizeof sregs->interrupt_bitmap);
1504
1505         vcpu_put(vcpu);
1506
1507         return 0;
1508 }
1509
1510 static void set_segment(struct kvm_vcpu *vcpu,
1511                         struct kvm_segment *var, int seg)
1512 {
1513         return kvm_arch_ops->set_segment(vcpu, var, seg);
1514 }
1515
1516 static int kvm_dev_ioctl_set_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
1517 {
1518         struct kvm_vcpu *vcpu;
1519         int mmu_reset_needed = 0;
1520         int i;
1521         struct descriptor_table dt;
1522
1523         if (!valid_vcpu(sregs->vcpu))
1524                 return -EINVAL;
1525         vcpu = vcpu_load(kvm, sregs->vcpu);
1526         if (!vcpu)
1527                 return -ENOENT;
1528
1529         set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
1530         set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
1531         set_segment(vcpu, &sregs->es, VCPU_SREG_ES);
1532         set_segment(vcpu, &sregs->fs, VCPU_SREG_FS);
1533         set_segment(vcpu, &sregs->gs, VCPU_SREG_GS);
1534         set_segment(vcpu, &sregs->ss, VCPU_SREG_SS);
1535
1536         set_segment(vcpu, &sregs->tr, VCPU_SREG_TR);
1537         set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
1538
1539         dt.limit = sregs->idt.limit;
1540         dt.base = sregs->idt.base;
1541         kvm_arch_ops->set_idt(vcpu, &dt);
1542         dt.limit = sregs->gdt.limit;
1543         dt.base = sregs->gdt.base;
1544         kvm_arch_ops->set_gdt(vcpu, &dt);
1545
1546         vcpu->cr2 = sregs->cr2;
1547         mmu_reset_needed |= vcpu->cr3 != sregs->cr3;
1548         vcpu->cr3 = sregs->cr3;
1549
1550         vcpu->cr8 = sregs->cr8;
1551
1552         mmu_reset_needed |= vcpu->shadow_efer != sregs->efer;
1553 #ifdef CONFIG_X86_64
1554         kvm_arch_ops->set_efer(vcpu, sregs->efer);
1555 #endif
1556         vcpu->apic_base = sregs->apic_base;
1557
1558         kvm_arch_ops->decache_cr0_cr4_guest_bits(vcpu);
1559
1560         mmu_reset_needed |= vcpu->cr0 != sregs->cr0;
1561         kvm_arch_ops->set_cr0_no_modeswitch(vcpu, sregs->cr0);
1562
1563         mmu_reset_needed |= vcpu->cr4 != sregs->cr4;
1564         kvm_arch_ops->set_cr4(vcpu, sregs->cr4);
1565         if (!is_long_mode(vcpu) && is_pae(vcpu))
1566                 load_pdptrs(vcpu, vcpu->cr3);
1567
1568         if (mmu_reset_needed)
1569                 kvm_mmu_reset_context(vcpu);
1570
1571         memcpy(vcpu->irq_pending, sregs->interrupt_bitmap,
1572                sizeof vcpu->irq_pending);
1573         vcpu->irq_summary = 0;
1574         for (i = 0; i < NR_IRQ_WORDS; ++i)
1575                 if (vcpu->irq_pending[i])
1576                         __set_bit(i, &vcpu->irq_summary);
1577
1578         vcpu_put(vcpu);
1579
1580         return 0;
1581 }
1582
1583 /*
1584  * List of msr numbers which we expose to userspace through KVM_GET_MSRS
1585  * and KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.
1586  *
1587  * This list is modified at module load time to reflect the
1588  * capabilities of the host cpu.
1589  */
1590 static u32 msrs_to_save[] = {
1591         MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
1592         MSR_K6_STAR,
1593 #ifdef CONFIG_X86_64
1594         MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
1595 #endif
1596         MSR_IA32_TIME_STAMP_COUNTER,
1597 };
1598
1599 static unsigned num_msrs_to_save;
1600
1601 static __init void kvm_init_msr_list(void)
1602 {
1603         u32 dummy[2];
1604         unsigned i, j;
1605
1606         for (i = j = 0; i < ARRAY_SIZE(msrs_to_save); i++) {
1607                 if (rdmsr_safe(msrs_to_save[i], &dummy[0], &dummy[1]) < 0)
1608                         continue;
1609                 if (j < i)
1610                         msrs_to_save[j] = msrs_to_save[i];
1611                 j++;
1612         }
1613         num_msrs_to_save = j;
1614 }
1615
1616 /*
1617  * Adapt set_msr() to msr_io()'s calling convention
1618  */
1619 static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
1620 {
1621         return set_msr(vcpu, index, *data);
1622 }
1623
1624 /*
1625  * Read or write a bunch of msrs. All parameters are kernel addresses.
1626  *
1627  * @return number of msrs set successfully.
1628  */
1629 static int __msr_io(struct kvm *kvm, struct kvm_msrs *msrs,
1630                     struct kvm_msr_entry *entries,
1631                     int (*do_msr)(struct kvm_vcpu *vcpu,
1632                                   unsigned index, u64 *data))
1633 {
1634         struct kvm_vcpu *vcpu;
1635         int i;
1636
1637         if (!valid_vcpu(msrs->vcpu))
1638                 return -EINVAL;
1639
1640         vcpu = vcpu_load(kvm, msrs->vcpu);
1641         if (!vcpu)
1642                 return -ENOENT;
1643
1644         for (i = 0; i < msrs->nmsrs; ++i)
1645                 if (do_msr(vcpu, entries[i].index, &entries[i].data))
1646                         break;
1647
1648         vcpu_put(vcpu);
1649
1650         return i;
1651 }
1652
1653 /*
1654  * Read or write a bunch of msrs. Parameters are user addresses.
1655  *
1656  * @return number of msrs set successfully.
1657  */
1658 static int msr_io(struct kvm *kvm, struct kvm_msrs __user *user_msrs,
1659                   int (*do_msr)(struct kvm_vcpu *vcpu,
1660                                 unsigned index, u64 *data),
1661                   int writeback)
1662 {
1663         struct kvm_msrs msrs;
1664         struct kvm_msr_entry *entries;
1665         int r, n;
1666         unsigned size;
1667
1668         r = -EFAULT;
1669         if (copy_from_user(&msrs, user_msrs, sizeof msrs))
1670                 goto out;
1671
1672         r = -E2BIG;
1673         if (msrs.nmsrs >= MAX_IO_MSRS)
1674                 goto out;
1675
1676         r = -ENOMEM;
1677         size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
1678         entries = vmalloc(size);
1679         if (!entries)
1680                 goto out;
1681
1682         r = -EFAULT;
1683         if (copy_from_user(entries, user_msrs->entries, size))
1684                 goto out_free;
1685
1686         r = n = __msr_io(kvm, &msrs, entries, do_msr);
1687         if (r < 0)
1688                 goto out_free;
1689
1690         r = -EFAULT;
1691         if (writeback && copy_to_user(user_msrs->entries, entries, size))
1692                 goto out_free;
1693
1694         r = n;
1695
1696 out_free:
1697         vfree(entries);
1698 out:
1699         return r;
1700 }
1701
1702 /*
1703  * Translate a guest virtual address to a guest physical address.
1704  */
1705 static int kvm_dev_ioctl_translate(struct kvm *kvm, struct kvm_translation *tr)
1706 {
1707         unsigned long vaddr = tr->linear_address;
1708         struct kvm_vcpu *vcpu;
1709         gpa_t gpa;
1710
1711         vcpu = vcpu_load(kvm, tr->vcpu);
1712         if (!vcpu)
1713                 return -ENOENT;
1714         spin_lock(&kvm->lock);
1715         gpa = vcpu->mmu.gva_to_gpa(vcpu, vaddr);
1716         tr->physical_address = gpa;
1717         tr->valid = gpa != UNMAPPED_GVA;
1718         tr->writeable = 1;
1719         tr->usermode = 0;
1720         spin_unlock(&kvm->lock);
1721         vcpu_put(vcpu);
1722
1723         return 0;
1724 }
1725
1726 static int kvm_dev_ioctl_interrupt(struct kvm *kvm, struct kvm_interrupt *irq)
1727 {
1728         struct kvm_vcpu *vcpu;
1729
1730         if (!valid_vcpu(irq->vcpu))
1731                 return -EINVAL;
1732         if (irq->irq < 0 || irq->irq >= 256)
1733                 return -EINVAL;
1734         vcpu = vcpu_load(kvm, irq->vcpu);
1735         if (!vcpu)
1736                 return -ENOENT;
1737
1738         set_bit(irq->irq, vcpu->irq_pending);
1739         set_bit(irq->irq / BITS_PER_LONG, &vcpu->irq_summary);
1740
1741         vcpu_put(vcpu);
1742
1743         return 0;
1744 }
1745
1746 static int kvm_dev_ioctl_debug_guest(struct kvm *kvm,
1747                                      struct kvm_debug_guest *dbg)
1748 {
1749         struct kvm_vcpu *vcpu;
1750         int r;
1751
1752         if (!valid_vcpu(dbg->vcpu))
1753                 return -EINVAL;
1754         vcpu = vcpu_load(kvm, dbg->vcpu);
1755         if (!vcpu)
1756                 return -ENOENT;
1757
1758         r = kvm_arch_ops->set_guest_debug(vcpu, dbg);
1759
1760         vcpu_put(vcpu);
1761
1762         return r;
1763 }
1764
1765 static long kvm_dev_ioctl(struct file *filp,
1766                           unsigned int ioctl, unsigned long arg)
1767 {
1768         struct kvm *kvm = filp->private_data;
1769         int r = -EINVAL;
1770
1771         switch (ioctl) {
1772         case KVM_GET_API_VERSION:
1773                 r = KVM_API_VERSION;
1774                 break;
1775         case KVM_CREATE_VCPU: {
1776                 r = kvm_dev_ioctl_create_vcpu(kvm, arg);
1777                 if (r)
1778                         goto out;
1779                 break;
1780         }
1781         case KVM_RUN: {
1782                 struct kvm_run kvm_run;
1783
1784                 r = -EFAULT;
1785                 if (copy_from_user(&kvm_run, (void *)arg, sizeof kvm_run))
1786                         goto out;
1787                 r = kvm_dev_ioctl_run(kvm, &kvm_run);
1788                 if (r < 0 &&  r != -EINTR)
1789                         goto out;
1790                 if (copy_to_user((void *)arg, &kvm_run, sizeof kvm_run)) {
1791                         r = -EFAULT;
1792                         goto out;
1793                 }
1794                 break;
1795         }
1796         case KVM_GET_REGS: {
1797                 struct kvm_regs kvm_regs;
1798
1799                 r = -EFAULT;
1800                 if (copy_from_user(&kvm_regs, (void *)arg, sizeof kvm_regs))
1801                         goto out;
1802                 r = kvm_dev_ioctl_get_regs(kvm, &kvm_regs);
1803                 if (r)
1804                         goto out;
1805                 r = -EFAULT;
1806                 if (copy_to_user((void *)arg, &kvm_regs, sizeof kvm_regs))
1807                         goto out;
1808                 r = 0;
1809                 break;
1810         }
1811         case KVM_SET_REGS: {
1812                 struct kvm_regs kvm_regs;
1813
1814                 r = -EFAULT;
1815                 if (copy_from_user(&kvm_regs, (void *)arg, sizeof kvm_regs))
1816                         goto out;
1817                 r = kvm_dev_ioctl_set_regs(kvm, &kvm_regs);
1818                 if (r)
1819                         goto out;
1820                 r = 0;
1821                 break;
1822         }
1823         case KVM_GET_SREGS: {
1824                 struct kvm_sregs kvm_sregs;
1825
1826                 r = -EFAULT;
1827                 if (copy_from_user(&kvm_sregs, (void *)arg, sizeof kvm_sregs))
1828                         goto out;
1829                 r = kvm_dev_ioctl_get_sregs(kvm, &kvm_sregs);
1830                 if (r)
1831                         goto out;
1832                 r = -EFAULT;
1833                 if (copy_to_user((void *)arg, &kvm_sregs, sizeof kvm_sregs))
1834                         goto out;
1835                 r = 0;
1836                 break;
1837         }
1838         case KVM_SET_SREGS: {
1839                 struct kvm_sregs kvm_sregs;
1840
1841                 r = -EFAULT;
1842                 if (copy_from_user(&kvm_sregs, (void *)arg, sizeof kvm_sregs))
1843                         goto out;
1844                 r = kvm_dev_ioctl_set_sregs(kvm, &kvm_sregs);
1845                 if (r)
1846                         goto out;
1847                 r = 0;
1848                 break;
1849         }
1850         case KVM_TRANSLATE: {
1851                 struct kvm_translation tr;
1852
1853                 r = -EFAULT;
1854                 if (copy_from_user(&tr, (void *)arg, sizeof tr))
1855                         goto out;
1856                 r = kvm_dev_ioctl_translate(kvm, &tr);
1857                 if (r)
1858                         goto out;
1859                 r = -EFAULT;
1860                 if (copy_to_user((void *)arg, &tr, sizeof tr))
1861                         goto out;
1862                 r = 0;
1863                 break;
1864         }
1865         case KVM_INTERRUPT: {
1866                 struct kvm_interrupt irq;
1867
1868                 r = -EFAULT;
1869                 if (copy_from_user(&irq, (void *)arg, sizeof irq))
1870                         goto out;
1871                 r = kvm_dev_ioctl_interrupt(kvm, &irq);
1872                 if (r)
1873                         goto out;
1874                 r = 0;
1875                 break;
1876         }
1877         case KVM_DEBUG_GUEST: {
1878                 struct kvm_debug_guest dbg;
1879
1880                 r = -EFAULT;
1881                 if (copy_from_user(&dbg, (void *)arg, sizeof dbg))
1882                         goto out;
1883                 r = kvm_dev_ioctl_debug_guest(kvm, &dbg);
1884                 if (r)
1885                         goto out;
1886                 r = 0;
1887                 break;
1888         }
1889         case KVM_SET_MEMORY_REGION: {
1890                 struct kvm_memory_region kvm_mem;
1891
1892                 r = -EFAULT;
1893                 if (copy_from_user(&kvm_mem, (void *)arg, sizeof kvm_mem))
1894                         goto out;
1895                 r = kvm_dev_ioctl_set_memory_region(kvm, &kvm_mem);
1896                 if (r)
1897                         goto out;
1898                 break;
1899         }
1900         case KVM_GET_DIRTY_LOG: {
1901                 struct kvm_dirty_log log;
1902
1903                 r = -EFAULT;
1904                 if (copy_from_user(&log, (void *)arg, sizeof log))
1905                         goto out;
1906                 r = kvm_dev_ioctl_get_dirty_log(kvm, &log);
1907                 if (r)
1908                         goto out;
1909                 break;
1910         }
1911         case KVM_GET_MSRS:
1912                 r = msr_io(kvm, (void __user *)arg, get_msr, 1);
1913                 break;
1914         case KVM_SET_MSRS:
1915                 r = msr_io(kvm, (void __user *)arg, do_set_msr, 0);
1916                 break;
1917         case KVM_GET_MSR_INDEX_LIST: {
1918                 struct kvm_msr_list __user *user_msr_list = (void __user *)arg;
1919                 struct kvm_msr_list msr_list;
1920                 unsigned n;
1921
1922                 r = -EFAULT;
1923                 if (copy_from_user(&msr_list, user_msr_list, sizeof msr_list))
1924                         goto out;
1925                 n = msr_list.nmsrs;
1926                 msr_list.nmsrs = num_msrs_to_save;
1927                 if (copy_to_user(user_msr_list, &msr_list, sizeof msr_list))
1928                         goto out;
1929                 r = -E2BIG;
1930                 if (n < num_msrs_to_save)
1931                         goto out;
1932                 r = -EFAULT;
1933                 if (copy_to_user(user_msr_list->indices, &msrs_to_save,
1934                                  num_msrs_to_save * sizeof(u32)))
1935                         goto out;
1936                 r = 0;
1937                 break;
1938         }
1939         default:
1940                 ;
1941         }
1942 out:
1943         return r;
1944 }
1945
1946 static struct page *kvm_dev_nopage(struct vm_area_struct *vma,
1947                                    unsigned long address,
1948                                    int *type)
1949 {
1950         struct kvm *kvm = vma->vm_file->private_data;
1951         unsigned long pgoff;
1952         struct kvm_memory_slot *slot;
1953         struct page *page;
1954
1955         *type = VM_FAULT_MINOR;
1956         pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
1957         slot = gfn_to_memslot(kvm, pgoff);
1958         if (!slot)
1959                 return NOPAGE_SIGBUS;
1960         page = gfn_to_page(slot, pgoff);
1961         if (!page)
1962                 return NOPAGE_SIGBUS;
1963         get_page(page);
1964         return page;
1965 }
1966
1967 static struct vm_operations_struct kvm_dev_vm_ops = {
1968         .nopage = kvm_dev_nopage,
1969 };
1970
1971 static int kvm_dev_mmap(struct file *file, struct vm_area_struct *vma)
1972 {
1973         vma->vm_ops = &kvm_dev_vm_ops;
1974         return 0;
1975 }
1976
1977 static struct file_operations kvm_chardev_ops = {
1978         .open           = kvm_dev_open,
1979         .release        = kvm_dev_release,
1980         .unlocked_ioctl = kvm_dev_ioctl,
1981         .compat_ioctl   = kvm_dev_ioctl,
1982         .mmap           = kvm_dev_mmap,
1983 };
1984
1985 static struct miscdevice kvm_dev = {
1986         MISC_DYNAMIC_MINOR,
1987         "kvm",
1988         &kvm_chardev_ops,
1989 };
1990
1991 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1992                        void *v)
1993 {
1994         if (val == SYS_RESTART) {
1995                 /*
1996                  * Some (well, at least mine) BIOSes hang on reboot if
1997                  * in vmx root mode.
1998                  */
1999                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
2000                 on_each_cpu(kvm_arch_ops->hardware_disable, 0, 0, 1);
2001         }
2002         return NOTIFY_OK;
2003 }
2004
2005 static struct notifier_block kvm_reboot_notifier = {
2006         .notifier_call = kvm_reboot,
2007         .priority = 0,
2008 };
2009
2010 static __init void kvm_init_debug(void)
2011 {
2012         struct kvm_stats_debugfs_item *p;
2013
2014         debugfs_dir = debugfs_create_dir("kvm", 0);
2015         for (p = debugfs_entries; p->name; ++p)
2016                 p->dentry = debugfs_create_u32(p->name, 0444, debugfs_dir,
2017                                                p->data);
2018 }
2019
2020 static void kvm_exit_debug(void)
2021 {
2022         struct kvm_stats_debugfs_item *p;
2023
2024         for (p = debugfs_entries; p->name; ++p)
2025                 debugfs_remove(p->dentry);
2026         debugfs_remove(debugfs_dir);
2027 }
2028
2029 hpa_t bad_page_address;
2030
2031 int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module)
2032 {
2033         int r;
2034
2035         if (kvm_arch_ops) {
2036                 printk(KERN_ERR "kvm: already loaded the other module\n");
2037                 return -EEXIST;
2038         }
2039
2040         if (!ops->cpu_has_kvm_support()) {
2041                 printk(KERN_ERR "kvm: no hardware support\n");
2042                 return -EOPNOTSUPP;
2043         }
2044         if (ops->disabled_by_bios()) {
2045                 printk(KERN_ERR "kvm: disabled by bios\n");
2046                 return -EOPNOTSUPP;
2047         }
2048
2049         kvm_arch_ops = ops;
2050
2051         r = kvm_arch_ops->hardware_setup();
2052         if (r < 0)
2053             return r;
2054
2055         on_each_cpu(kvm_arch_ops->hardware_enable, 0, 0, 1);
2056         register_reboot_notifier(&kvm_reboot_notifier);
2057
2058         kvm_chardev_ops.owner = module;
2059
2060         r = misc_register(&kvm_dev);
2061         if (r) {
2062                 printk (KERN_ERR "kvm: misc device register failed\n");
2063                 goto out_free;
2064         }
2065
2066         return r;
2067
2068 out_free:
2069         unregister_reboot_notifier(&kvm_reboot_notifier);
2070         on_each_cpu(kvm_arch_ops->hardware_disable, 0, 0, 1);
2071         kvm_arch_ops->hardware_unsetup();
2072         return r;
2073 }
2074
2075 void kvm_exit_arch(void)
2076 {
2077         misc_deregister(&kvm_dev);
2078
2079         unregister_reboot_notifier(&kvm_reboot_notifier);
2080         on_each_cpu(kvm_arch_ops->hardware_disable, 0, 0, 1);
2081         kvm_arch_ops->hardware_unsetup();
2082         kvm_arch_ops = NULL;
2083 }
2084
2085 static __init int kvm_init(void)
2086 {
2087         static struct page *bad_page;
2088         int r = 0;
2089
2090         kvm_init_debug();
2091
2092         kvm_init_msr_list();
2093
2094         if ((bad_page = alloc_page(GFP_KERNEL)) == NULL) {
2095                 r = -ENOMEM;
2096                 goto out;
2097         }
2098
2099         bad_page_address = page_to_pfn(bad_page) << PAGE_SHIFT;
2100         memset(__va(bad_page_address), 0, PAGE_SIZE);
2101
2102         return r;
2103
2104 out:
2105         kvm_exit_debug();
2106         return r;
2107 }
2108
2109 static __exit void kvm_exit(void)
2110 {
2111         kvm_exit_debug();
2112         __free_page(pfn_to_page(bad_page_address >> PAGE_SHIFT));
2113 }
2114
2115 module_init(kvm_init)
2116 module_exit(kvm_exit)
2117
2118 EXPORT_SYMBOL_GPL(kvm_init_arch);
2119 EXPORT_SYMBOL_GPL(kvm_exit_arch);