KVM: Add coalesced MMIO support (powerpc part)
[linux-2.6.git] / arch / powerpc / kvm / powerpc.c
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License, version 2, as
4  * published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9  * GNU General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with this program; if not, write to the Free Software
13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
14  *
15  * Copyright IBM Corp. 2007
16  *
17  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
18  *          Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
19  */
20
21 #include <linux/errno.h>
22 #include <linux/err.h>
23 #include <linux/kvm_host.h>
24 #include <linux/module.h>
25 #include <linux/vmalloc.h>
26 #include <linux/fs.h>
27 #include <asm/cputable.h>
28 #include <asm/uaccess.h>
29 #include <asm/kvm_ppc.h>
30
31
32 gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
33 {
34         return gfn;
35 }
36
37 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
38 {
39         return !!(v->arch.pending_exceptions);
40 }
41
42 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
43 {
44         return !(v->arch.msr & MSR_WE);
45 }
46
47
48 int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
49 {
50         enum emulation_result er;
51         int r;
52
53         er = kvmppc_emulate_instruction(run, vcpu);
54         switch (er) {
55         case EMULATE_DONE:
56                 /* Future optimization: only reload non-volatiles if they were
57                  * actually modified. */
58                 r = RESUME_GUEST_NV;
59                 break;
60         case EMULATE_DO_MMIO:
61                 run->exit_reason = KVM_EXIT_MMIO;
62                 /* We must reload nonvolatiles because "update" load/store
63                  * instructions modify register state. */
64                 /* Future optimization: only reload non-volatiles if they were
65                  * actually modified. */
66                 r = RESUME_HOST_NV;
67                 break;
68         case EMULATE_FAIL:
69                 /* XXX Deliver Program interrupt to guest. */
70                 printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
71                        vcpu->arch.last_inst);
72                 r = RESUME_HOST;
73                 break;
74         default:
75                 BUG();
76         }
77
78         return r;
79 }
80
81 void kvm_arch_hardware_enable(void *garbage)
82 {
83 }
84
85 void kvm_arch_hardware_disable(void *garbage)
86 {
87 }
88
89 int kvm_arch_hardware_setup(void)
90 {
91         return 0;
92 }
93
94 void kvm_arch_hardware_unsetup(void)
95 {
96 }
97
98 void kvm_arch_check_processor_compat(void *rtn)
99 {
100         int r;
101
102         if (strcmp(cur_cpu_spec->platform, "ppc440") == 0)
103                 r = 0;
104         else
105                 r = -ENOTSUPP;
106
107         *(int *)rtn = r;
108 }
109
110 struct kvm *kvm_arch_create_vm(void)
111 {
112         struct kvm *kvm;
113
114         kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
115         if (!kvm)
116                 return ERR_PTR(-ENOMEM);
117
118         return kvm;
119 }
120
121 static void kvmppc_free_vcpus(struct kvm *kvm)
122 {
123         unsigned int i;
124
125         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
126                 if (kvm->vcpus[i]) {
127                         kvm_arch_vcpu_free(kvm->vcpus[i]);
128                         kvm->vcpus[i] = NULL;
129                 }
130         }
131 }
132
133 void kvm_arch_destroy_vm(struct kvm *kvm)
134 {
135         kvmppc_free_vcpus(kvm);
136         kvm_free_physmem(kvm);
137         kfree(kvm);
138 }
139
140 int kvm_dev_ioctl_check_extension(long ext)
141 {
142         int r;
143
144         switch (ext) {
145         case KVM_CAP_USER_MEMORY:
146                 r = 1;
147                 break;
148         case KVM_CAP_COALESCED_MMIO:
149                 r = KVM_COALESCED_MMIO_PAGE_OFFSET;
150                 break;
151         default:
152                 r = 0;
153                 break;
154         }
155         return r;
156
157 }
158
159 long kvm_arch_dev_ioctl(struct file *filp,
160                         unsigned int ioctl, unsigned long arg)
161 {
162         return -EINVAL;
163 }
164
165 int kvm_arch_set_memory_region(struct kvm *kvm,
166                                struct kvm_userspace_memory_region *mem,
167                                struct kvm_memory_slot old,
168                                int user_alloc)
169 {
170         return 0;
171 }
172
173 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
174 {
175         struct kvm_vcpu *vcpu;
176         int err;
177
178         vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
179         if (!vcpu) {
180                 err = -ENOMEM;
181                 goto out;
182         }
183
184         err = kvm_vcpu_init(vcpu, kvm, id);
185         if (err)
186                 goto free_vcpu;
187
188         return vcpu;
189
190 free_vcpu:
191         kmem_cache_free(kvm_vcpu_cache, vcpu);
192 out:
193         return ERR_PTR(err);
194 }
195
196 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
197 {
198         kvm_vcpu_uninit(vcpu);
199         kmem_cache_free(kvm_vcpu_cache, vcpu);
200 }
201
202 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
203 {
204         kvm_arch_vcpu_free(vcpu);
205 }
206
207 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
208 {
209         unsigned int priority = exception_priority[BOOKE_INTERRUPT_DECREMENTER];
210
211         return test_bit(priority, &vcpu->arch.pending_exceptions);
212 }
213
214 static void kvmppc_decrementer_func(unsigned long data)
215 {
216         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
217
218         kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_DECREMENTER);
219
220         if (waitqueue_active(&vcpu->wq)) {
221                 wake_up_interruptible(&vcpu->wq);
222                 vcpu->stat.halt_wakeup++;
223         }
224 }
225
226 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
227 {
228         setup_timer(&vcpu->arch.dec_timer, kvmppc_decrementer_func,
229                     (unsigned long)vcpu);
230
231         return 0;
232 }
233
234 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
235 {
236 }
237
238 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
239 {
240 }
241
242 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
243 {
244 }
245
246 int kvm_arch_vcpu_ioctl_debug_guest(struct kvm_vcpu *vcpu,
247                                     struct kvm_debug_guest *dbg)
248 {
249         return -ENOTSUPP;
250 }
251
252 static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
253                                      struct kvm_run *run)
254 {
255         u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
256         *gpr = run->dcr.data;
257 }
258
259 static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
260                                       struct kvm_run *run)
261 {
262         u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
263
264         if (run->mmio.len > sizeof(*gpr)) {
265                 printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
266                 return;
267         }
268
269         if (vcpu->arch.mmio_is_bigendian) {
270                 switch (run->mmio.len) {
271                 case 4: *gpr = *(u32 *)run->mmio.data; break;
272                 case 2: *gpr = *(u16 *)run->mmio.data; break;
273                 case 1: *gpr = *(u8 *)run->mmio.data; break;
274                 }
275         } else {
276                 /* Convert BE data from userland back to LE. */
277                 switch (run->mmio.len) {
278                 case 4: *gpr = ld_le32((u32 *)run->mmio.data); break;
279                 case 2: *gpr = ld_le16((u16 *)run->mmio.data); break;
280                 case 1: *gpr = *(u8 *)run->mmio.data; break;
281                 }
282         }
283 }
284
285 int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
286                        unsigned int rt, unsigned int bytes, int is_bigendian)
287 {
288         if (bytes > sizeof(run->mmio.data)) {
289                 printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
290                        run->mmio.len);
291         }
292
293         run->mmio.phys_addr = vcpu->arch.paddr_accessed;
294         run->mmio.len = bytes;
295         run->mmio.is_write = 0;
296
297         vcpu->arch.io_gpr = rt;
298         vcpu->arch.mmio_is_bigendian = is_bigendian;
299         vcpu->mmio_needed = 1;
300         vcpu->mmio_is_write = 0;
301
302         return EMULATE_DO_MMIO;
303 }
304
305 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
306                         u32 val, unsigned int bytes, int is_bigendian)
307 {
308         void *data = run->mmio.data;
309
310         if (bytes > sizeof(run->mmio.data)) {
311                 printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
312                        run->mmio.len);
313         }
314
315         run->mmio.phys_addr = vcpu->arch.paddr_accessed;
316         run->mmio.len = bytes;
317         run->mmio.is_write = 1;
318         vcpu->mmio_needed = 1;
319         vcpu->mmio_is_write = 1;
320
321         /* Store the value at the lowest bytes in 'data'. */
322         if (is_bigendian) {
323                 switch (bytes) {
324                 case 4: *(u32 *)data = val; break;
325                 case 2: *(u16 *)data = val; break;
326                 case 1: *(u8  *)data = val; break;
327                 }
328         } else {
329                 /* Store LE value into 'data'. */
330                 switch (bytes) {
331                 case 4: st_le32(data, val); break;
332                 case 2: st_le16(data, val); break;
333                 case 1: *(u8 *)data = val; break;
334                 }
335         }
336
337         return EMULATE_DO_MMIO;
338 }
339
340 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
341 {
342         int r;
343         sigset_t sigsaved;
344
345         vcpu_load(vcpu);
346
347         if (vcpu->sigset_active)
348                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
349
350         if (vcpu->mmio_needed) {
351                 if (!vcpu->mmio_is_write)
352                         kvmppc_complete_mmio_load(vcpu, run);
353                 vcpu->mmio_needed = 0;
354         } else if (vcpu->arch.dcr_needed) {
355                 if (!vcpu->arch.dcr_is_write)
356                         kvmppc_complete_dcr_load(vcpu, run);
357                 vcpu->arch.dcr_needed = 0;
358         }
359
360         kvmppc_check_and_deliver_interrupts(vcpu);
361
362         local_irq_disable();
363         kvm_guest_enter();
364         r = __kvmppc_vcpu_run(run, vcpu);
365         kvm_guest_exit();
366         local_irq_enable();
367
368         if (vcpu->sigset_active)
369                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
370
371         vcpu_put(vcpu);
372
373         return r;
374 }
375
376 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
377 {
378         kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_EXTERNAL);
379
380         if (waitqueue_active(&vcpu->wq)) {
381                 wake_up_interruptible(&vcpu->wq);
382                 vcpu->stat.halt_wakeup++;
383         }
384
385         return 0;
386 }
387
388 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
389                                     struct kvm_mp_state *mp_state)
390 {
391         return -EINVAL;
392 }
393
394 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
395                                     struct kvm_mp_state *mp_state)
396 {
397         return -EINVAL;
398 }
399
400 long kvm_arch_vcpu_ioctl(struct file *filp,
401                          unsigned int ioctl, unsigned long arg)
402 {
403         struct kvm_vcpu *vcpu = filp->private_data;
404         void __user *argp = (void __user *)arg;
405         long r;
406
407         switch (ioctl) {
408         case KVM_INTERRUPT: {
409                 struct kvm_interrupt irq;
410                 r = -EFAULT;
411                 if (copy_from_user(&irq, argp, sizeof(irq)))
412                         goto out;
413                 r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
414                 break;
415         }
416         default:
417                 r = -EINVAL;
418         }
419
420 out:
421         return r;
422 }
423
424 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
425 {
426         return -ENOTSUPP;
427 }
428
429 long kvm_arch_vm_ioctl(struct file *filp,
430                        unsigned int ioctl, unsigned long arg)
431 {
432         long r;
433
434         switch (ioctl) {
435         default:
436                 r = -EINVAL;
437         }
438
439         return r;
440 }
441
442 int kvm_arch_init(void *opaque)
443 {
444         return 0;
445 }
446
447 void kvm_arch_exit(void)
448 {
449 }