powerpc.c 14 KB

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  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. #include <linux/errno.h>
  21. #include <linux/err.h>
  22. #include <linux/kvm_host.h>
  23. #include <linux/module.h>
  24. #include <linux/vmalloc.h>
  25. #include <linux/hrtimer.h>
  26. #include <linux/fs.h>
  27. #include <linux/slab.h>
  28. #include <asm/cputable.h>
  29. #include <asm/uaccess.h>
  30. #include <asm/kvm_ppc.h>
  31. #include <asm/tlbflush.h>
  32. #include "timing.h"
  33. #include "../mm/mmu_decl.h"
  34. #define CREATE_TRACE_POINTS
  35. #include "trace.h"
  36. int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
  37. {
  38. return !(v->arch.shared->msr & MSR_WE) ||
  39. !!(v->arch.pending_exceptions);
  40. }
  41. int kvmppc_kvm_pv(struct kvm_vcpu *vcpu)
  42. {
  43. int nr = kvmppc_get_gpr(vcpu, 11);
  44. int r;
  45. unsigned long __maybe_unused param1 = kvmppc_get_gpr(vcpu, 3);
  46. unsigned long __maybe_unused param2 = kvmppc_get_gpr(vcpu, 4);
  47. unsigned long __maybe_unused param3 = kvmppc_get_gpr(vcpu, 5);
  48. unsigned long __maybe_unused param4 = kvmppc_get_gpr(vcpu, 6);
  49. unsigned long r2 = 0;
  50. if (!(vcpu->arch.shared->msr & MSR_SF)) {
  51. /* 32 bit mode */
  52. param1 &= 0xffffffff;
  53. param2 &= 0xffffffff;
  54. param3 &= 0xffffffff;
  55. param4 &= 0xffffffff;
  56. }
  57. switch (nr) {
  58. case HC_VENDOR_KVM | KVM_HC_PPC_MAP_MAGIC_PAGE:
  59. {
  60. vcpu->arch.magic_page_pa = param1;
  61. vcpu->arch.magic_page_ea = param2;
  62. r2 = KVM_MAGIC_FEAT_SR;
  63. r = HC_EV_SUCCESS;
  64. break;
  65. }
  66. case HC_VENDOR_KVM | KVM_HC_FEATURES:
  67. r = HC_EV_SUCCESS;
  68. #if defined(CONFIG_PPC_BOOK3S) || defined(CONFIG_KVM_E500)
  69. /* XXX Missing magic page on 44x */
  70. r2 |= (1 << KVM_FEATURE_MAGIC_PAGE);
  71. #endif
  72. /* Second return value is in r4 */
  73. break;
  74. default:
  75. r = HC_EV_UNIMPLEMENTED;
  76. break;
  77. }
  78. kvmppc_set_gpr(vcpu, 4, r2);
  79. return r;
  80. }
  81. int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
  82. {
  83. enum emulation_result er;
  84. int r;
  85. er = kvmppc_emulate_instruction(run, vcpu);
  86. switch (er) {
  87. case EMULATE_DONE:
  88. /* Future optimization: only reload non-volatiles if they were
  89. * actually modified. */
  90. r = RESUME_GUEST_NV;
  91. break;
  92. case EMULATE_DO_MMIO:
  93. run->exit_reason = KVM_EXIT_MMIO;
  94. /* We must reload nonvolatiles because "update" load/store
  95. * instructions modify register state. */
  96. /* Future optimization: only reload non-volatiles if they were
  97. * actually modified. */
  98. r = RESUME_HOST_NV;
  99. break;
  100. case EMULATE_FAIL:
  101. /* XXX Deliver Program interrupt to guest. */
  102. printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
  103. kvmppc_get_last_inst(vcpu));
  104. r = RESUME_HOST;
  105. break;
  106. default:
  107. BUG();
  108. }
  109. return r;
  110. }
  111. int kvm_arch_hardware_enable(void *garbage)
  112. {
  113. return 0;
  114. }
  115. void kvm_arch_hardware_disable(void *garbage)
  116. {
  117. }
  118. int kvm_arch_hardware_setup(void)
  119. {
  120. return 0;
  121. }
  122. void kvm_arch_hardware_unsetup(void)
  123. {
  124. }
  125. void kvm_arch_check_processor_compat(void *rtn)
  126. {
  127. *(int *)rtn = kvmppc_core_check_processor_compat();
  128. }
  129. int kvm_arch_init_vm(struct kvm *kvm)
  130. {
  131. return 0;
  132. }
  133. void kvm_arch_destroy_vm(struct kvm *kvm)
  134. {
  135. unsigned int i;
  136. struct kvm_vcpu *vcpu;
  137. kvm_for_each_vcpu(i, vcpu, kvm)
  138. kvm_arch_vcpu_free(vcpu);
  139. mutex_lock(&kvm->lock);
  140. for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
  141. kvm->vcpus[i] = NULL;
  142. atomic_set(&kvm->online_vcpus, 0);
  143. mutex_unlock(&kvm->lock);
  144. }
  145. void kvm_arch_sync_events(struct kvm *kvm)
  146. {
  147. }
  148. int kvm_dev_ioctl_check_extension(long ext)
  149. {
  150. int r;
  151. switch (ext) {
  152. #ifdef CONFIG_BOOKE
  153. case KVM_CAP_PPC_BOOKE_SREGS:
  154. #else
  155. case KVM_CAP_PPC_SEGSTATE:
  156. #endif
  157. case KVM_CAP_PPC_PAIRED_SINGLES:
  158. case KVM_CAP_PPC_UNSET_IRQ:
  159. case KVM_CAP_PPC_IRQ_LEVEL:
  160. case KVM_CAP_ENABLE_CAP:
  161. case KVM_CAP_PPC_OSI:
  162. case KVM_CAP_PPC_GET_PVINFO:
  163. r = 1;
  164. break;
  165. case KVM_CAP_COALESCED_MMIO:
  166. r = KVM_COALESCED_MMIO_PAGE_OFFSET;
  167. break;
  168. default:
  169. r = 0;
  170. break;
  171. }
  172. return r;
  173. }
  174. long kvm_arch_dev_ioctl(struct file *filp,
  175. unsigned int ioctl, unsigned long arg)
  176. {
  177. return -EINVAL;
  178. }
  179. int kvm_arch_prepare_memory_region(struct kvm *kvm,
  180. struct kvm_memory_slot *memslot,
  181. struct kvm_memory_slot old,
  182. struct kvm_userspace_memory_region *mem,
  183. int user_alloc)
  184. {
  185. return 0;
  186. }
  187. void kvm_arch_commit_memory_region(struct kvm *kvm,
  188. struct kvm_userspace_memory_region *mem,
  189. struct kvm_memory_slot old,
  190. int user_alloc)
  191. {
  192. return;
  193. }
  194. void kvm_arch_flush_shadow(struct kvm *kvm)
  195. {
  196. }
  197. struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
  198. {
  199. struct kvm_vcpu *vcpu;
  200. vcpu = kvmppc_core_vcpu_create(kvm, id);
  201. if (!IS_ERR(vcpu))
  202. kvmppc_create_vcpu_debugfs(vcpu, id);
  203. return vcpu;
  204. }
  205. void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
  206. {
  207. /* Make sure we're not using the vcpu anymore */
  208. hrtimer_cancel(&vcpu->arch.dec_timer);
  209. tasklet_kill(&vcpu->arch.tasklet);
  210. kvmppc_remove_vcpu_debugfs(vcpu);
  211. kvmppc_core_vcpu_free(vcpu);
  212. }
  213. void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
  214. {
  215. kvm_arch_vcpu_free(vcpu);
  216. }
  217. int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
  218. {
  219. return kvmppc_core_pending_dec(vcpu);
  220. }
  221. static void kvmppc_decrementer_func(unsigned long data)
  222. {
  223. struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
  224. kvmppc_core_queue_dec(vcpu);
  225. if (waitqueue_active(&vcpu->wq)) {
  226. wake_up_interruptible(&vcpu->wq);
  227. vcpu->stat.halt_wakeup++;
  228. }
  229. }
  230. /*
  231. * low level hrtimer wake routine. Because this runs in hardirq context
  232. * we schedule a tasklet to do the real work.
  233. */
  234. enum hrtimer_restart kvmppc_decrementer_wakeup(struct hrtimer *timer)
  235. {
  236. struct kvm_vcpu *vcpu;
  237. vcpu = container_of(timer, struct kvm_vcpu, arch.dec_timer);
  238. tasklet_schedule(&vcpu->arch.tasklet);
  239. return HRTIMER_NORESTART;
  240. }
  241. int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
  242. {
  243. hrtimer_init(&vcpu->arch.dec_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
  244. tasklet_init(&vcpu->arch.tasklet, kvmppc_decrementer_func, (ulong)vcpu);
  245. vcpu->arch.dec_timer.function = kvmppc_decrementer_wakeup;
  246. #ifdef CONFIG_KVM_EXIT_TIMING
  247. mutex_init(&vcpu->arch.exit_timing_lock);
  248. #endif
  249. return 0;
  250. }
  251. void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
  252. {
  253. kvmppc_mmu_destroy(vcpu);
  254. }
  255. void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
  256. {
  257. #ifdef CONFIG_BOOKE
  258. /*
  259. * vrsave (formerly usprg0) isn't used by Linux, but may
  260. * be used by the guest.
  261. *
  262. * On non-booke this is associated with Altivec and
  263. * is handled by code in book3s.c.
  264. */
  265. mtspr(SPRN_VRSAVE, vcpu->arch.vrsave);
  266. #endif
  267. kvmppc_core_vcpu_load(vcpu, cpu);
  268. }
  269. void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
  270. {
  271. kvmppc_core_vcpu_put(vcpu);
  272. #ifdef CONFIG_BOOKE
  273. vcpu->arch.vrsave = mfspr(SPRN_VRSAVE);
  274. #endif
  275. }
  276. int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
  277. struct kvm_guest_debug *dbg)
  278. {
  279. return -EINVAL;
  280. }
  281. static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
  282. struct kvm_run *run)
  283. {
  284. kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, run->dcr.data);
  285. }
  286. static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
  287. struct kvm_run *run)
  288. {
  289. u64 uninitialized_var(gpr);
  290. if (run->mmio.len > sizeof(gpr)) {
  291. printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
  292. return;
  293. }
  294. if (vcpu->arch.mmio_is_bigendian) {
  295. switch (run->mmio.len) {
  296. case 8: gpr = *(u64 *)run->mmio.data; break;
  297. case 4: gpr = *(u32 *)run->mmio.data; break;
  298. case 2: gpr = *(u16 *)run->mmio.data; break;
  299. case 1: gpr = *(u8 *)run->mmio.data; break;
  300. }
  301. } else {
  302. /* Convert BE data from userland back to LE. */
  303. switch (run->mmio.len) {
  304. case 4: gpr = ld_le32((u32 *)run->mmio.data); break;
  305. case 2: gpr = ld_le16((u16 *)run->mmio.data); break;
  306. case 1: gpr = *(u8 *)run->mmio.data; break;
  307. }
  308. }
  309. if (vcpu->arch.mmio_sign_extend) {
  310. switch (run->mmio.len) {
  311. #ifdef CONFIG_PPC64
  312. case 4:
  313. gpr = (s64)(s32)gpr;
  314. break;
  315. #endif
  316. case 2:
  317. gpr = (s64)(s16)gpr;
  318. break;
  319. case 1:
  320. gpr = (s64)(s8)gpr;
  321. break;
  322. }
  323. }
  324. kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
  325. switch (vcpu->arch.io_gpr & KVM_REG_EXT_MASK) {
  326. case KVM_REG_GPR:
  327. kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
  328. break;
  329. case KVM_REG_FPR:
  330. vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
  331. break;
  332. #ifdef CONFIG_PPC_BOOK3S
  333. case KVM_REG_QPR:
  334. vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
  335. break;
  336. case KVM_REG_FQPR:
  337. vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
  338. vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
  339. break;
  340. #endif
  341. default:
  342. BUG();
  343. }
  344. }
  345. int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
  346. unsigned int rt, unsigned int bytes, int is_bigendian)
  347. {
  348. if (bytes > sizeof(run->mmio.data)) {
  349. printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
  350. run->mmio.len);
  351. }
  352. run->mmio.phys_addr = vcpu->arch.paddr_accessed;
  353. run->mmio.len = bytes;
  354. run->mmio.is_write = 0;
  355. vcpu->arch.io_gpr = rt;
  356. vcpu->arch.mmio_is_bigendian = is_bigendian;
  357. vcpu->mmio_needed = 1;
  358. vcpu->mmio_is_write = 0;
  359. vcpu->arch.mmio_sign_extend = 0;
  360. return EMULATE_DO_MMIO;
  361. }
  362. /* Same as above, but sign extends */
  363. int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
  364. unsigned int rt, unsigned int bytes, int is_bigendian)
  365. {
  366. int r;
  367. r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
  368. vcpu->arch.mmio_sign_extend = 1;
  369. return r;
  370. }
  371. int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
  372. u64 val, unsigned int bytes, int is_bigendian)
  373. {
  374. void *data = run->mmio.data;
  375. if (bytes > sizeof(run->mmio.data)) {
  376. printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
  377. run->mmio.len);
  378. }
  379. run->mmio.phys_addr = vcpu->arch.paddr_accessed;
  380. run->mmio.len = bytes;
  381. run->mmio.is_write = 1;
  382. vcpu->mmio_needed = 1;
  383. vcpu->mmio_is_write = 1;
  384. /* Store the value at the lowest bytes in 'data'. */
  385. if (is_bigendian) {
  386. switch (bytes) {
  387. case 8: *(u64 *)data = val; break;
  388. case 4: *(u32 *)data = val; break;
  389. case 2: *(u16 *)data = val; break;
  390. case 1: *(u8 *)data = val; break;
  391. }
  392. } else {
  393. /* Store LE value into 'data'. */
  394. switch (bytes) {
  395. case 4: st_le32(data, val); break;
  396. case 2: st_le16(data, val); break;
  397. case 1: *(u8 *)data = val; break;
  398. }
  399. }
  400. return EMULATE_DO_MMIO;
  401. }
  402. int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
  403. {
  404. int r;
  405. sigset_t sigsaved;
  406. if (vcpu->sigset_active)
  407. sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
  408. if (vcpu->mmio_needed) {
  409. if (!vcpu->mmio_is_write)
  410. kvmppc_complete_mmio_load(vcpu, run);
  411. vcpu->mmio_needed = 0;
  412. } else if (vcpu->arch.dcr_needed) {
  413. if (!vcpu->arch.dcr_is_write)
  414. kvmppc_complete_dcr_load(vcpu, run);
  415. vcpu->arch.dcr_needed = 0;
  416. } else if (vcpu->arch.osi_needed) {
  417. u64 *gprs = run->osi.gprs;
  418. int i;
  419. for (i = 0; i < 32; i++)
  420. kvmppc_set_gpr(vcpu, i, gprs[i]);
  421. vcpu->arch.osi_needed = 0;
  422. }
  423. kvmppc_core_deliver_interrupts(vcpu);
  424. local_irq_disable();
  425. kvm_guest_enter();
  426. r = __kvmppc_vcpu_run(run, vcpu);
  427. kvm_guest_exit();
  428. local_irq_enable();
  429. if (vcpu->sigset_active)
  430. sigprocmask(SIG_SETMASK, &sigsaved, NULL);
  431. return r;
  432. }
  433. int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
  434. {
  435. if (irq->irq == KVM_INTERRUPT_UNSET)
  436. kvmppc_core_dequeue_external(vcpu, irq);
  437. else
  438. kvmppc_core_queue_external(vcpu, irq);
  439. if (waitqueue_active(&vcpu->wq)) {
  440. wake_up_interruptible(&vcpu->wq);
  441. vcpu->stat.halt_wakeup++;
  442. }
  443. return 0;
  444. }
  445. static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
  446. struct kvm_enable_cap *cap)
  447. {
  448. int r;
  449. if (cap->flags)
  450. return -EINVAL;
  451. switch (cap->cap) {
  452. case KVM_CAP_PPC_OSI:
  453. r = 0;
  454. vcpu->arch.osi_enabled = true;
  455. break;
  456. default:
  457. r = -EINVAL;
  458. break;
  459. }
  460. return r;
  461. }
  462. int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
  463. struct kvm_mp_state *mp_state)
  464. {
  465. return -EINVAL;
  466. }
  467. int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
  468. struct kvm_mp_state *mp_state)
  469. {
  470. return -EINVAL;
  471. }
  472. long kvm_arch_vcpu_ioctl(struct file *filp,
  473. unsigned int ioctl, unsigned long arg)
  474. {
  475. struct kvm_vcpu *vcpu = filp->private_data;
  476. void __user *argp = (void __user *)arg;
  477. long r;
  478. switch (ioctl) {
  479. case KVM_INTERRUPT: {
  480. struct kvm_interrupt irq;
  481. r = -EFAULT;
  482. if (copy_from_user(&irq, argp, sizeof(irq)))
  483. goto out;
  484. r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
  485. goto out;
  486. }
  487. case KVM_ENABLE_CAP:
  488. {
  489. struct kvm_enable_cap cap;
  490. r = -EFAULT;
  491. if (copy_from_user(&cap, argp, sizeof(cap)))
  492. goto out;
  493. r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
  494. break;
  495. }
  496. default:
  497. r = -EINVAL;
  498. }
  499. out:
  500. return r;
  501. }
  502. static int kvm_vm_ioctl_get_pvinfo(struct kvm_ppc_pvinfo *pvinfo)
  503. {
  504. u32 inst_lis = 0x3c000000;
  505. u32 inst_ori = 0x60000000;
  506. u32 inst_nop = 0x60000000;
  507. u32 inst_sc = 0x44000002;
  508. u32 inst_imm_mask = 0xffff;
  509. /*
  510. * The hypercall to get into KVM from within guest context is as
  511. * follows:
  512. *
  513. * lis r0, r0, KVM_SC_MAGIC_R0@h
  514. * ori r0, KVM_SC_MAGIC_R0@l
  515. * sc
  516. * nop
  517. */
  518. pvinfo->hcall[0] = inst_lis | ((KVM_SC_MAGIC_R0 >> 16) & inst_imm_mask);
  519. pvinfo->hcall[1] = inst_ori | (KVM_SC_MAGIC_R0 & inst_imm_mask);
  520. pvinfo->hcall[2] = inst_sc;
  521. pvinfo->hcall[3] = inst_nop;
  522. return 0;
  523. }
  524. long kvm_arch_vm_ioctl(struct file *filp,
  525. unsigned int ioctl, unsigned long arg)
  526. {
  527. void __user *argp = (void __user *)arg;
  528. long r;
  529. switch (ioctl) {
  530. case KVM_PPC_GET_PVINFO: {
  531. struct kvm_ppc_pvinfo pvinfo;
  532. memset(&pvinfo, 0, sizeof(pvinfo));
  533. r = kvm_vm_ioctl_get_pvinfo(&pvinfo);
  534. if (copy_to_user(argp, &pvinfo, sizeof(pvinfo))) {
  535. r = -EFAULT;
  536. goto out;
  537. }
  538. break;
  539. }
  540. default:
  541. r = -ENOTTY;
  542. }
  543. out:
  544. return r;
  545. }
  546. int kvm_arch_init(void *opaque)
  547. {
  548. return 0;
  549. }
  550. void kvm_arch_exit(void)
  551. {
  552. }