1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corporation, 2018
4 * Authors Suraj Jitindar Singh <sjitindarsingh@gmail.com>
5 * Paul Mackerras <paulus@ozlabs.org>
6 *
7 * Description: KVM functions specific to running nested KVM-HV guests
8 * on Book3S processors (specifically POWER9 and later).
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/kvm_host.h>
13 #include <linux/llist.h>
14 #include <linux/pgtable.h>
15
16 #include <asm/kvm_ppc.h>
17 #include <asm/kvm_book3s.h>
18 #include <asm/mmu.h>
19 #include <asm/pgalloc.h>
20 #include <asm/pte-walk.h>
21 #include <asm/reg.h>
22 #include <asm/plpar_wrappers.h>
23 #include <asm/firmware.h>
24
25 static struct patb_entry *pseries_partition_tb;
26
27 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp);
28 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free);
29
30 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
31 {
32 struct kvmppc_vcore *vc = vcpu->arch.vcore;
33
34 hr->pcr = vc->pcr | PCR_MASK;
35 hr->dpdes = vc->dpdes;
36 hr->hfscr = vcpu->arch.hfscr;
37 hr->tb_offset = vc->tb_offset;
38 hr->dawr0 = vcpu->arch.dawr0;
39 hr->dawrx0 = vcpu->arch.dawrx0;
40 hr->ciabr = vcpu->arch.ciabr;
41 hr->purr = vcpu->arch.purr;
42 hr->spurr = vcpu->arch.spurr;
43 hr->ic = vcpu->arch.ic;
44 hr->vtb = vc->vtb;
45 hr->srr0 = vcpu->arch.shregs.srr0;
46 hr->srr1 = vcpu->arch.shregs.srr1;
47 hr->sprg[0] = vcpu->arch.shregs.sprg0;
48 hr->sprg[1] = vcpu->arch.shregs.sprg1;
49 hr->sprg[2] = vcpu->arch.shregs.sprg2;
50 hr->sprg[3] = vcpu->arch.shregs.sprg3;
51 hr->pidr = vcpu->arch.pid;
52 hr->cfar = vcpu->arch.cfar;
53 hr->ppr = vcpu->arch.ppr;
54 hr->dawr1 = vcpu->arch.dawr1;
55 hr->dawrx1 = vcpu->arch.dawrx1;
56 }
57
58 /* Use noinline_for_stack due to https://llvm.org/pr49610 */
59 static noinline_for_stack void byteswap_pt_regs(struct pt_regs *regs)
60 {
61 unsigned long *addr = (unsigned long *) regs;
62
63 for (; addr < ((unsigned long *) (regs + 1)); addr++)
64 *addr = swab64(*addr);
65 }
66
67 static void byteswap_hv_regs(struct hv_guest_state *hr)
68 {
69 hr->version = swab64(hr->version);
70 hr->lpid = swab32(hr->lpid);
71 hr->vcpu_token = swab32(hr->vcpu_token);
72 hr->lpcr = swab64(hr->lpcr);
73 hr->pcr = swab64(hr->pcr) | PCR_MASK;
74 hr->amor = swab64(hr->amor);
75 hr->dpdes = swab64(hr->dpdes);
76 hr->hfscr = swab64(hr->hfscr);
77 hr->tb_offset = swab64(hr->tb_offset);
78 hr->dawr0 = swab64(hr->dawr0);
79 hr->dawrx0 = swab64(hr->dawrx0);
80 hr->ciabr = swab64(hr->ciabr);
81 hr->hdec_expiry = swab64(hr->hdec_expiry);
82 hr->purr = swab64(hr->purr);
83 hr->spurr = swab64(hr->spurr);
84 hr->ic = swab64(hr->ic);
85 hr->vtb = swab64(hr->vtb);
86 hr->hdar = swab64(hr->hdar);
87 hr->hdsisr = swab64(hr->hdsisr);
88 hr->heir = swab64(hr->heir);
89 hr->asdr = swab64(hr->asdr);
90 hr->srr0 = swab64(hr->srr0);
91 hr->srr1 = swab64(hr->srr1);
92 hr->sprg[0] = swab64(hr->sprg[0]);
93 hr->sprg[1] = swab64(hr->sprg[1]);
94 hr->sprg[2] = swab64(hr->sprg[2]);
95 hr->sprg[3] = swab64(hr->sprg[3]);
96 hr->pidr = swab64(hr->pidr);
97 hr->cfar = swab64(hr->cfar);
98 hr->ppr = swab64(hr->ppr);
99 hr->dawr1 = swab64(hr->dawr1);
100 hr->dawrx1 = swab64(hr->dawrx1);
101 }
102
103 static void save_hv_return_state(struct kvm_vcpu *vcpu,
104 struct hv_guest_state *hr)
105 {
106 struct kvmppc_vcore *vc = vcpu->arch.vcore;
107
108 hr->dpdes = vc->dpdes;
109 hr->purr = vcpu->arch.purr;
110 hr->spurr = vcpu->arch.spurr;
111 hr->ic = vcpu->arch.ic;
112 hr->vtb = vc->vtb;
113 hr->srr0 = vcpu->arch.shregs.srr0;
114 hr->srr1 = vcpu->arch.shregs.srr1;
115 hr->sprg[0] = vcpu->arch.shregs.sprg0;
116 hr->sprg[1] = vcpu->arch.shregs.sprg1;
117 hr->sprg[2] = vcpu->arch.shregs.sprg2;
118 hr->sprg[3] = vcpu->arch.shregs.sprg3;
119 hr->pidr = vcpu->arch.pid;
120 hr->cfar = vcpu->arch.cfar;
121 hr->ppr = vcpu->arch.ppr;
122 switch (vcpu->arch.trap) {
123 case BOOK3S_INTERRUPT_H_DATA_STORAGE:
124 hr->hdar = vcpu->arch.fault_dar;
125 hr->hdsisr = vcpu->arch.fault_dsisr;
126 hr->asdr = vcpu->arch.fault_gpa;
127 break;
128 case BOOK3S_INTERRUPT_H_INST_STORAGE:
129 hr->asdr = vcpu->arch.fault_gpa;
130 break;
131 case BOOK3S_INTERRUPT_H_FAC_UNAVAIL:
132 hr->hfscr = ((~HFSCR_INTR_CAUSE & hr->hfscr) |
133 (HFSCR_INTR_CAUSE & vcpu->arch.hfscr));
134 break;
135 case BOOK3S_INTERRUPT_H_EMUL_ASSIST:
136 hr->heir = vcpu->arch.emul_inst;
137 break;
138 }
139 }
140
141 static void restore_hv_regs(struct kvm_vcpu *vcpu, const struct hv_guest_state *hr)
142 {
143 struct kvmppc_vcore *vc = vcpu->arch.vcore;
144
145 vc->pcr = hr->pcr | PCR_MASK;
146 vc->dpdes = hr->dpdes;
147 vcpu->arch.hfscr = hr->hfscr;
148 vcpu->arch.dawr0 = hr->dawr0;
149 vcpu->arch.dawrx0 = hr->dawrx0;
150 vcpu->arch.ciabr = hr->ciabr;
151 vcpu->arch.purr = hr->purr;
152 vcpu->arch.spurr = hr->spurr;
153 vcpu->arch.ic = hr->ic;
154 vc->vtb = hr->vtb;
155 vcpu->arch.shregs.srr0 = hr->srr0;
156 vcpu->arch.shregs.srr1 = hr->srr1;
157 vcpu->arch.shregs.sprg0 = hr->sprg[0];
158 vcpu->arch.shregs.sprg1 = hr->sprg[1];
159 vcpu->arch.shregs.sprg2 = hr->sprg[2];
160 vcpu->arch.shregs.sprg3 = hr->sprg[3];
161 vcpu->arch.pid = hr->pidr;
162 vcpu->arch.cfar = hr->cfar;
163 vcpu->arch.ppr = hr->ppr;
164 vcpu->arch.dawr1 = hr->dawr1;
165 vcpu->arch.dawrx1 = hr->dawrx1;
166 }
167
168 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
169 struct hv_guest_state *hr)
170 {
171 struct kvmppc_vcore *vc = vcpu->arch.vcore;
172
173 vc->dpdes = hr->dpdes;
174 vcpu->arch.hfscr = hr->hfscr;
175 vcpu->arch.purr = hr->purr;
176 vcpu->arch.spurr = hr->spurr;
177 vcpu->arch.ic = hr->ic;
178 vc->vtb = hr->vtb;
179 vcpu->arch.fault_dar = hr->hdar;
180 vcpu->arch.fault_dsisr = hr->hdsisr;
181 vcpu->arch.fault_gpa = hr->asdr;
182 vcpu->arch.emul_inst = hr->heir;
183 vcpu->arch.shregs.srr0 = hr->srr0;
184 vcpu->arch.shregs.srr1 = hr->srr1;
185 vcpu->arch.shregs.sprg0 = hr->sprg[0];
186 vcpu->arch.shregs.sprg1 = hr->sprg[1];
187 vcpu->arch.shregs.sprg2 = hr->sprg[2];
188 vcpu->arch.shregs.sprg3 = hr->sprg[3];
189 vcpu->arch.pid = hr->pidr;
190 vcpu->arch.cfar = hr->cfar;
191 vcpu->arch.ppr = hr->ppr;
192 }
193
194 static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr)
195 {
196 /* No need to reflect the page fault to L1, we've handled it */
197 vcpu->arch.trap = 0;
198
199 /*
200 * Since the L2 gprs have already been written back into L1 memory when
201 * we complete the mmio, store the L1 memory location of the L2 gpr
202 * being loaded into by the mmio so that the loaded value can be
203 * written there in kvmppc_complete_mmio_load()
204 */
205 if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR)
206 && (vcpu->mmio_is_write == 0)) {
207 vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr +
208 offsetof(struct pt_regs,
209 gpr[vcpu->arch.io_gpr]);
210 vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR;
211 }
212 }
213
214 static int kvmhv_read_guest_state_and_regs(struct kvm_vcpu *vcpu,
215 struct hv_guest_state *l2_hv,
216 struct pt_regs *l2_regs,
217 u64 hv_ptr, u64 regs_ptr)
218 {
219 int size;
220
221 if (kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv->version,
222 sizeof(l2_hv->version)))
223 return -1;
224
225 if (kvmppc_need_byteswap(vcpu))
226 l2_hv->version = swab64(l2_hv->version);
227
228 size = hv_guest_state_size(l2_hv->version);
229 if (size < 0)
230 return -1;
231
232 return kvm_vcpu_read_guest(vcpu, hv_ptr, l2_hv, size) ||
233 kvm_vcpu_read_guest(vcpu, regs_ptr, l2_regs,
234 sizeof(struct pt_regs));
235 }
236
237 static int kvmhv_write_guest_state_and_regs(struct kvm_vcpu *vcpu,
238 struct hv_guest_state *l2_hv,
239 struct pt_regs *l2_regs,
240 u64 hv_ptr, u64 regs_ptr)
241 {
242 int size;
243
244 size = hv_guest_state_size(l2_hv->version);
245 if (size < 0)
246 return -1;
247
248 return kvm_vcpu_write_guest(vcpu, hv_ptr, l2_hv, size) ||
249 kvm_vcpu_write_guest(vcpu, regs_ptr, l2_regs,
250 sizeof(struct pt_regs));
251 }
252
253 static void load_l2_hv_regs(struct kvm_vcpu *vcpu,
254 const struct hv_guest_state *l2_hv,
255 const struct hv_guest_state *l1_hv, u64 *lpcr)
256 {
257 struct kvmppc_vcore *vc = vcpu->arch.vcore;
258 u64 mask;
259
260 restore_hv_regs(vcpu, l2_hv);
261
262 /*
263 * Don't let L1 change LPCR bits for the L2 except these:
264 */
265 mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | LPCR_MER;
266
267 /*
268 * Additional filtering is required depending on hardware
269 * and configuration.
270 */
271 *lpcr = kvmppc_filter_lpcr_hv(vcpu->kvm,
272 (vc->lpcr & ~mask) | (*lpcr & mask));
273
274 /*
275 * Don't let L1 enable features for L2 which we don't allow for L1,
276 * but preserve the interrupt cause field.
277 */
278 vcpu->arch.hfscr = l2_hv->hfscr & (HFSCR_INTR_CAUSE | vcpu->arch.hfscr_permitted);
279
280 /* Don't let data address watchpoint match in hypervisor state */
281 vcpu->arch.dawrx0 = l2_hv->dawrx0 & ~DAWRX_HYP;
282 vcpu->arch.dawrx1 = l2_hv->dawrx1 & ~DAWRX_HYP;
283
284 /* Don't let completed instruction address breakpt match in HV state */
285 if ((l2_hv->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER)
286 vcpu->arch.ciabr = l2_hv->ciabr & ~CIABR_PRIV;
287 }
288
289 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
290 {
291 long int err, r;
292 struct kvm_nested_guest *l2;
293 struct pt_regs l2_regs, saved_l1_regs;
294 struct hv_guest_state l2_hv = {0}, saved_l1_hv;
295 struct kvmppc_vcore *vc = vcpu->arch.vcore;
296 u64 hv_ptr, regs_ptr;
297 u64 hdec_exp, lpcr;
298 s64 delta_purr, delta_spurr, delta_ic, delta_vtb;
299
300 if (vcpu->kvm->arch.l1_ptcr == 0)
301 return H_NOT_AVAILABLE;
302
303 if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
304 return H_BAD_MODE;
305
306 /* copy parameters in */
307 hv_ptr = kvmppc_get_gpr(vcpu, 4);
308 regs_ptr = kvmppc_get_gpr(vcpu, 5);
309 kvm_vcpu_srcu_read_lock(vcpu);
310 err = kvmhv_read_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
311 hv_ptr, regs_ptr);
312 kvm_vcpu_srcu_read_unlock(vcpu);
313 if (err)
314 return H_PARAMETER;
315
316 if (kvmppc_need_byteswap(vcpu))
317 byteswap_hv_regs(&l2_hv);
318 if (l2_hv.version > HV_GUEST_STATE_VERSION)
319 return H_P2;
320
321 if (kvmppc_need_byteswap(vcpu))
322 byteswap_pt_regs(&l2_regs);
323 if (l2_hv.vcpu_token >= NR_CPUS)
324 return H_PARAMETER;
325
326 /*
327 * L1 must have set up a suspended state to enter the L2 in a
328 * transactional state, and only in that case. These have to be
329 * filtered out here to prevent causing a TM Bad Thing in the
330 * host HRFID. We could synthesize a TM Bad Thing back to the L1
331 * here but there doesn't seem like much point.
332 */
333 if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr)) {
334 if (!MSR_TM_ACTIVE(l2_regs.msr))
335 return H_BAD_MODE;
336 } else {
337 if (l2_regs.msr & MSR_TS_MASK)
338 return H_BAD_MODE;
339 if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_TS_MASK))
340 return H_BAD_MODE;
341 }
342
343 /* translate lpid */
344 l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true);
345 if (!l2)
346 return H_PARAMETER;
347 if (!l2->l1_gr_to_hr) {
348 mutex_lock(&l2->tlb_lock);
349 kvmhv_update_ptbl_cache(l2);
350 mutex_unlock(&l2->tlb_lock);
351 }
352
353 /* save l1 values of things */
354 vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
355 saved_l1_regs = vcpu->arch.regs;
356 kvmhv_save_hv_regs(vcpu, &saved_l1_hv);
357
358 /* convert TB values/offsets to host (L0) values */
359 hdec_exp = l2_hv.hdec_expiry - vc->tb_offset;
360 vc->tb_offset += l2_hv.tb_offset;
361 vcpu->arch.dec_expires += l2_hv.tb_offset;
362
363 /* set L1 state to L2 state */
364 vcpu->arch.nested = l2;
365 vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token;
366 vcpu->arch.nested_hfscr = l2_hv.hfscr;
367 vcpu->arch.regs = l2_regs;
368
369 /* Guest must always run with ME enabled, HV disabled. */
370 vcpu->arch.shregs.msr = (vcpu->arch.regs.msr | MSR_ME) & ~MSR_HV;
371
372 lpcr = l2_hv.lpcr;
373 load_l2_hv_regs(vcpu, &l2_hv, &saved_l1_hv, &lpcr);
374
375 vcpu->arch.ret = RESUME_GUEST;
376 vcpu->arch.trap = 0;
377 do {
378 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, lpcr);
379 } while (is_kvmppc_resume_guest(r));
380
381 /* save L2 state for return */
382 l2_regs = vcpu->arch.regs;
383 l2_regs.msr = vcpu->arch.shregs.msr;
384 delta_purr = vcpu->arch.purr - l2_hv.purr;
385 delta_spurr = vcpu->arch.spurr - l2_hv.spurr;
386 delta_ic = vcpu->arch.ic - l2_hv.ic;
387 delta_vtb = vc->vtb - l2_hv.vtb;
388 save_hv_return_state(vcpu, &l2_hv);
389
390 /* restore L1 state */
391 vcpu->arch.nested = NULL;
392 vcpu->arch.regs = saved_l1_regs;
393 vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK;
394 /* set L1 MSR TS field according to L2 transaction state */
395 if (l2_regs.msr & MSR_TS_MASK)
396 vcpu->arch.shregs.msr |= MSR_TS_S;
397 vc->tb_offset = saved_l1_hv.tb_offset;
398 /* XXX: is this always the same delta as saved_l1_hv.tb_offset? */
399 vcpu->arch.dec_expires -= l2_hv.tb_offset;
400 restore_hv_regs(vcpu, &saved_l1_hv);
401 vcpu->arch.purr += delta_purr;
402 vcpu->arch.spurr += delta_spurr;
403 vcpu->arch.ic += delta_ic;
404 vc->vtb += delta_vtb;
405
406 kvmhv_put_nested(l2);
407
408 /* copy l2_hv_state and regs back to guest */
409 if (kvmppc_need_byteswap(vcpu)) {
410 byteswap_hv_regs(&l2_hv);
411 byteswap_pt_regs(&l2_regs);
412 }
413 kvm_vcpu_srcu_read_lock(vcpu);
414 err = kvmhv_write_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
415 hv_ptr, regs_ptr);
416 kvm_vcpu_srcu_read_unlock(vcpu);
417 if (err)
418 return H_AUTHORITY;
419
420 if (r == -EINTR)
421 return H_INTERRUPT;
422
423 if (vcpu->mmio_needed) {
424 kvmhv_nested_mmio_needed(vcpu, regs_ptr);
425 return H_TOO_HARD;
426 }
427
428 return vcpu->arch.trap;
429 }
430
431 unsigned long nested_capabilities;
432
433 long kvmhv_nested_init(void)
434 {
435 long int ptb_order;
436 unsigned long ptcr, host_capabilities;
437 long rc;
438
439 if (!kvmhv_on_pseries())
440 return 0;
441 if (!radix_enabled())
442 return -ENODEV;
443
444 rc = plpar_guest_get_capabilities(0, &host_capabilities);
445 if (rc == H_SUCCESS) {
446 unsigned long capabilities = 0;
447
448 if (cpu_has_feature(CPU_FTR_ARCH_31))
449 capabilities |= H_GUEST_CAP_POWER10;
450 if (cpu_has_feature(CPU_FTR_ARCH_300))
451 capabilities |= H_GUEST_CAP_POWER9;
452
453 nested_capabilities = capabilities & host_capabilities;
454 rc = plpar_guest_set_capabilities(0, nested_capabilities);
455 if (rc != H_SUCCESS) {
456 pr_err("kvm-hv: Could not configure parent hypervisor capabilities (rc=%ld)",
457 rc);
458 return -ENODEV;
459 }
460
461 static_branch_enable(&__kvmhv_is_nestedv2);
462 return 0;
463 }
464
465 pr_info("kvm-hv: nestedv2 get capabilities hcall failed, falling back to nestedv1 (rc=%ld)\n",
466 rc);
467 /* Partition table entry is 1<<4 bytes in size, hence the 4. */
468 ptb_order = KVM_MAX_NESTED_GUESTS_SHIFT + 4;
469 /* Minimum partition table size is 1<<12 bytes */
470 if (ptb_order < 12)
471 ptb_order = 12;
472 pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order,
473 GFP_KERNEL);
474 if (!pseries_partition_tb) {
475 pr_err("kvm-hv: failed to allocated nested partition table\n");
476 return -ENOMEM;
477 }
478
479 ptcr = __pa(pseries_partition_tb) | (ptb_order - 12);
480 rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr);
481 if (rc != H_SUCCESS) {
482 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n",
483 rc);
484 kfree(pseries_partition_tb);
485 pseries_partition_tb = NULL;
486 return -ENODEV;
487 }
488
489 return 0;
490 }
491
492 void kvmhv_nested_exit(void)
493 {
494 /*
495 * N.B. the kvmhv_on_pseries() test is there because it enables
496 * the compiler to remove the call to plpar_hcall_norets()
497 * when CONFIG_PPC_PSERIES=n.
498 */
499 if (kvmhv_on_pseries() && pseries_partition_tb) {
500 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0);
501 kfree(pseries_partition_tb);
502 pseries_partition_tb = NULL;
503 }
504 }
505
506 void kvmhv_flush_lpid(u64 lpid)
507 {
508 long rc;
509
510 if (!kvmhv_on_pseries()) {
511 radix__flush_all_lpid(lpid);
512 return;
513 }
514
515 if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
516 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
517 lpid, TLBIEL_INVAL_SET_LPID);
518 else
519 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
520 H_RPTI_TYPE_NESTED |
521 H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
522 H_RPTI_TYPE_PAT,
523 H_RPTI_PAGE_ALL, 0, -1UL);
524 if (rc)
525 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
526 }
527
528 void kvmhv_set_ptbl_entry(u64 lpid, u64 dw0, u64 dw1)
529 {
530 if (!kvmhv_on_pseries()) {
531 mmu_partition_table_set_entry(lpid, dw0, dw1, true);
532 return;
533 }
534
535 if (kvmhv_is_nestedv1()) {
536 pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
537 pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
538 /* L0 will do the necessary barriers */
539 kvmhv_flush_lpid(lpid);
540 }
541
542 if (kvmhv_is_nestedv2())
543 kvmhv_nestedv2_set_ptbl_entry(lpid, dw0, dw1);
544 }
545
546 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
547 {
548 unsigned long dw0;
549
550 dw0 = PATB_HR | radix__get_tree_size() |
551 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE;
552 kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table);
553 }
554
555 /*
556 * Handle the H_SET_PARTITION_TABLE hcall.
557 * r4 = guest real address of partition table + log_2(size) - 12
558 * (formatted as for the PTCR).
559 */
560 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
561 {
562 struct kvm *kvm = vcpu->kvm;
563 unsigned long ptcr = kvmppc_get_gpr(vcpu, 4);
564 int srcu_idx;
565 long ret = H_SUCCESS;
566
567 srcu_idx = srcu_read_lock(&kvm->srcu);
568 /* Check partition size and base address. */
569 if ((ptcr & PRTS_MASK) + 12 - 4 > KVM_MAX_NESTED_GUESTS_SHIFT ||
570 !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT))
571 ret = H_PARAMETER;
572 srcu_read_unlock(&kvm->srcu, srcu_idx);
573 if (ret == H_SUCCESS)
574 kvm->arch.l1_ptcr = ptcr;
575
576 return ret;
577 }
578
579 /*
580 * Handle the H_COPY_TOFROM_GUEST hcall.
581 * r4 = L1 lpid of nested guest
582 * r5 = pid
583 * r6 = eaddr to access
584 * r7 = to buffer (L1 gpa)
585 * r8 = from buffer (L1 gpa)
586 * r9 = n bytes to copy
587 */
588 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
589 {
590 struct kvm_nested_guest *gp;
591 int l1_lpid = kvmppc_get_gpr(vcpu, 4);
592 int pid = kvmppc_get_gpr(vcpu, 5);
593 gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
594 gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
595 gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
596 void *buf;
597 unsigned long n = kvmppc_get_gpr(vcpu, 9);
598 bool is_load = !!gp_to;
599 long rc;
600
601 if (gp_to && gp_from) /* One must be NULL to determine the direction */
602 return H_PARAMETER;
603
604 if (eaddr & (0xFFFUL << 52))
605 return H_PARAMETER;
606
607 buf = kzalloc(n, GFP_KERNEL | __GFP_NOWARN);
608 if (!buf)
609 return H_NO_MEM;
610
611 gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
612 if (!gp) {
613 rc = H_PARAMETER;
614 goto out_free;
615 }
616
617 mutex_lock(&gp->tlb_lock);
618
619 if (is_load) {
620 /* Load from the nested guest into our buffer */
621 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
622 eaddr, buf, NULL, n);
623 if (rc)
624 goto not_found;
625
626 /* Write what was loaded into our buffer back to the L1 guest */
627 kvm_vcpu_srcu_read_lock(vcpu);
628 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
629 kvm_vcpu_srcu_read_unlock(vcpu);
630 if (rc)
631 goto not_found;
632 } else {
633 /* Load the data to be stored from the L1 guest into our buf */
634 kvm_vcpu_srcu_read_lock(vcpu);
635 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
636 kvm_vcpu_srcu_read_unlock(vcpu);
637 if (rc)
638 goto not_found;
639
640 /* Store from our buffer into the nested guest */
641 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
642 eaddr, NULL, buf, n);
643 if (rc)
644 goto not_found;
645 }
646
647 out_unlock:
648 mutex_unlock(&gp->tlb_lock);
649 kvmhv_put_nested(gp);
650 out_free:
651 kfree(buf);
652 return rc;
653 not_found:
654 rc = H_NOT_FOUND;
655 goto out_unlock;
656 }
657
658 /*
659 * Reload the partition table entry for a guest.
660 * Caller must hold gp->tlb_lock.
661 */
662 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
663 {
664 int ret;
665 struct patb_entry ptbl_entry;
666 unsigned long ptbl_addr;
667 struct kvm *kvm = gp->l1_host;
668
669 ret = -EFAULT;
670 ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4);
671 if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4))) {
672 int srcu_idx = srcu_read_lock(&kvm->srcu);
673 ret = kvm_read_guest(kvm, ptbl_addr,
674 &ptbl_entry, sizeof(ptbl_entry));
675 srcu_read_unlock(&kvm->srcu, srcu_idx);
676 }
677 if (ret) {
678 gp->l1_gr_to_hr = 0;
679 gp->process_table = 0;
680 } else {
681 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0);
682 gp->process_table = be64_to_cpu(ptbl_entry.patb1);
683 }
684 kvmhv_set_nested_ptbl(gp);
685 }
686
687 void kvmhv_vm_nested_init(struct kvm *kvm)
688 {
689 idr_init(&kvm->arch.kvm_nested_guest_idr);
690 }
691
692 static struct kvm_nested_guest *__find_nested(struct kvm *kvm, int lpid)
693 {
694 return idr_find(&kvm->arch.kvm_nested_guest_idr, lpid);
695 }
696
697 static bool __prealloc_nested(struct kvm *kvm, int lpid)
698 {
699 if (idr_alloc(&kvm->arch.kvm_nested_guest_idr,
700 NULL, lpid, lpid + 1, GFP_KERNEL) != lpid)
701 return false;
702 return true;
703 }
704
705 static void __add_nested(struct kvm *kvm, int lpid, struct kvm_nested_guest *gp)
706 {
707 if (idr_replace(&kvm->arch.kvm_nested_guest_idr, gp, lpid))
708 WARN_ON(1);
709 }
710
711 static void __remove_nested(struct kvm *kvm, int lpid)
712 {
713 idr_remove(&kvm->arch.kvm_nested_guest_idr, lpid);
714 }
715
716 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
717 {
718 struct kvm_nested_guest *gp;
719 long shadow_lpid;
720
721 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
722 if (!gp)
723 return NULL;
724 gp->l1_host = kvm;
725 gp->l1_lpid = lpid;
726 mutex_init(&gp->tlb_lock);
727 gp->shadow_pgtable = pgd_alloc(kvm->mm);
728 if (!gp->shadow_pgtable)
729 goto out_free;
730 shadow_lpid = kvmppc_alloc_lpid();
731 if (shadow_lpid < 0)
732 goto out_free2;
733 gp->shadow_lpid = shadow_lpid;
734 gp->radix = 1;
735
736 memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
737
738 return gp;
739
740 out_free2:
741 pgd_free(kvm->mm, gp->shadow_pgtable);
742 out_free:
743 kfree(gp);
744 return NULL;
745 }
746
747 /*
748 * Free up any resources allocated for a nested guest.
749 */
750 static void kvmhv_release_nested(struct kvm_nested_guest *gp)
751 {
752 struct kvm *kvm = gp->l1_host;
753
754 if (gp->shadow_pgtable) {
755 /*
756 * No vcpu is using this struct and no call to
757 * kvmhv_get_nested can find this struct,
758 * so we don't need to hold kvm->mmu_lock.
759 */
760 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
761 gp->shadow_lpid);
762 pgd_free(kvm->mm, gp->shadow_pgtable);
763 }
764 kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
765 kvmppc_free_lpid(gp->shadow_lpid);
766 kfree(gp);
767 }
768
769 static void kvmhv_remove_nested(struct kvm_nested_guest *gp)
770 {
771 struct kvm *kvm = gp->l1_host;
772 int lpid = gp->l1_lpid;
773 long ref;
774
775 spin_lock(&kvm->mmu_lock);
776 if (gp == __find_nested(kvm, lpid)) {
777 __remove_nested(kvm, lpid);
778 --gp->refcnt;
779 }
780 ref = gp->refcnt;
781 spin_unlock(&kvm->mmu_lock);
782 if (ref == 0)
783 kvmhv_release_nested(gp);
784 }
785
786 /*
787 * Free up all nested resources allocated for this guest.
788 * This is called with no vcpus of the guest running, when
789 * switching the guest to HPT mode or when destroying the
790 * guest.
791 */
792 void kvmhv_release_all_nested(struct kvm *kvm)
793 {
794 int lpid;
795 struct kvm_nested_guest *gp;
796 struct kvm_nested_guest *freelist = NULL;
797 struct kvm_memory_slot *memslot;
798 int srcu_idx, bkt;
799
800 spin_lock(&kvm->mmu_lock);
801 idr_for_each_entry(&kvm->arch.kvm_nested_guest_idr, gp, lpid) {
802 __remove_nested(kvm, lpid);
803 if (--gp->refcnt == 0) {
804 gp->next = freelist;
805 freelist = gp;
806 }
807 }
808 idr_destroy(&kvm->arch.kvm_nested_guest_idr);
809 /* idr is empty and may be reused at this point */
810 spin_unlock(&kvm->mmu_lock);
811 while ((gp = freelist) != NULL) {
812 freelist = gp->next;
813 kvmhv_release_nested(gp);
814 }
815
816 srcu_idx = srcu_read_lock(&kvm->srcu);
817 kvm_for_each_memslot(memslot, bkt, kvm_memslots(kvm))
818 kvmhv_free_memslot_nest_rmap(memslot);
819 srcu_read_unlock(&kvm->srcu, srcu_idx);
820 }
821
822 /* caller must hold gp->tlb_lock */
823 static void kvmhv_flush_nested(struct kvm_nested_guest *gp)
824 {
825 struct kvm *kvm = gp->l1_host;
826
827 spin_lock(&kvm->mmu_lock);
828 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid);
829 spin_unlock(&kvm->mmu_lock);
830 kvmhv_flush_lpid(gp->shadow_lpid);
831 kvmhv_update_ptbl_cache(gp);
832 if (gp->l1_gr_to_hr == 0)
833 kvmhv_remove_nested(gp);
834 }
835
836 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
837 bool create)
838 {
839 struct kvm_nested_guest *gp, *newgp;
840
841 if (l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4)))
842 return NULL;
843
844 spin_lock(&kvm->mmu_lock);
845 gp = __find_nested(kvm, l1_lpid);
846 if (gp)
847 ++gp->refcnt;
848 spin_unlock(&kvm->mmu_lock);
849
850 if (gp || !create)
851 return gp;
852
853 newgp = kvmhv_alloc_nested(kvm, l1_lpid);
854 if (!newgp)
855 return NULL;
856
857 if (!__prealloc_nested(kvm, l1_lpid)) {
858 kvmhv_release_nested(newgp);
859 return NULL;
860 }
861
862 spin_lock(&kvm->mmu_lock);
863 gp = __find_nested(kvm, l1_lpid);
864 if (!gp) {
865 __add_nested(kvm, l1_lpid, newgp);
866 ++newgp->refcnt;
867 gp = newgp;
868 newgp = NULL;
869 }
870 ++gp->refcnt;
871 spin_unlock(&kvm->mmu_lock);
872
873 if (newgp)
874 kvmhv_release_nested(newgp);
875
876 return gp;
877 }
878
879 void kvmhv_put_nested(struct kvm_nested_guest *gp)
880 {
881 struct kvm *kvm = gp->l1_host;
882 long ref;
883
884 spin_lock(&kvm->mmu_lock);
885 ref = --gp->refcnt;
886 spin_unlock(&kvm->mmu_lock);
887 if (ref == 0)
888 kvmhv_release_nested(gp);
889 }
890
891 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid,
892 unsigned long ea, unsigned *hshift)
893 {
894 struct kvm_nested_guest *gp;
895 pte_t *pte;
896
897 gp = __find_nested(kvm, lpid);
898 if (!gp)
899 return NULL;
900
901 VM_WARN(!spin_is_locked(&kvm->mmu_lock),
902 "%s called with kvm mmu_lock not held \n", __func__);
903 pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift);
904
905 return pte;
906 }
907
908 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
909 {
910 return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
911 RMAP_NESTED_GPA_MASK));
912 }
913
914 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
915 struct rmap_nested **n_rmap)
916 {
917 struct llist_node *entry = ((struct llist_head *) rmapp)->first;
918 struct rmap_nested *cursor;
919 u64 rmap, new_rmap = (*n_rmap)->rmap;
920
921 /* Are there any existing entries? */
922 if (!(*rmapp)) {
923 /* No -> use the rmap as a single entry */
924 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
925 return;
926 }
927
928 /* Do any entries match what we're trying to insert? */
929 for_each_nest_rmap_safe(cursor, entry, &rmap) {
930 if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
931 return;
932 }
933
934 /* Do we need to create a list or just add the new entry? */
935 rmap = *rmapp;
936 if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
937 *rmapp = 0UL;
938 llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
939 if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
940 (*n_rmap)->list.next = (struct llist_node *) rmap;
941
942 /* Set NULL so not freed by caller */
943 *n_rmap = NULL;
944 }
945
946 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
947 unsigned long clr, unsigned long set,
948 unsigned long hpa, unsigned long mask)
949 {
950 unsigned long gpa;
951 unsigned int shift, lpid;
952 pte_t *ptep;
953
954 gpa = n_rmap & RMAP_NESTED_GPA_MASK;
955 lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
956
957 /* Find the pte */
958 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
959 /*
960 * If the pte is present and the pfn is still the same, update the pte.
961 * If the pfn has changed then this is a stale rmap entry, the nested
962 * gpa actually points somewhere else now, and there is nothing to do.
963 * XXX A future optimisation would be to remove the rmap entry here.
964 */
965 if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
966 __radix_pte_update(ptep, clr, set);
967 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
968 }
969 }
970
971 /*
972 * For a given list of rmap entries, update the rc bits in all ptes in shadow
973 * page tables for nested guests which are referenced by the rmap list.
974 */
975 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
976 unsigned long clr, unsigned long set,
977 unsigned long hpa, unsigned long nbytes)
978 {
979 struct llist_node *entry = ((struct llist_head *) rmapp)->first;
980 struct rmap_nested *cursor;
981 unsigned long rmap, mask;
982
983 if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
984 return;
985
986 mask = PTE_RPN_MASK & ~(nbytes - 1);
987 hpa &= mask;
988
989 for_each_nest_rmap_safe(cursor, entry, &rmap)
990 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
991 }
992
993 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
994 unsigned long hpa, unsigned long mask)
995 {
996 struct kvm_nested_guest *gp;
997 unsigned long gpa;
998 unsigned int shift, lpid;
999 pte_t *ptep;
1000
1001 gpa = n_rmap & RMAP_NESTED_GPA_MASK;
1002 lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
1003 gp = __find_nested(kvm, lpid);
1004 if (!gp)
1005 return;
1006
1007 /* Find and invalidate the pte */
1008 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
1009 /* Don't spuriously invalidate ptes if the pfn has changed */
1010 if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
1011 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1012 }
1013
1014 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
1015 unsigned long hpa, unsigned long mask)
1016 {
1017 struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
1018 struct rmap_nested *cursor;
1019 unsigned long rmap;
1020
1021 for_each_nest_rmap_safe(cursor, entry, &rmap) {
1022 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
1023 kfree(cursor);
1024 }
1025 }
1026
1027 /* called with kvm->mmu_lock held */
1028 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
1029 const struct kvm_memory_slot *memslot,
1030 unsigned long gpa, unsigned long hpa,
1031 unsigned long nbytes)
1032 {
1033 unsigned long gfn, end_gfn;
1034 unsigned long addr_mask;
1035
1036 if (!memslot)
1037 return;
1038 gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
1039 end_gfn = gfn + (nbytes >> PAGE_SHIFT);
1040
1041 addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
1042 hpa &= addr_mask;
1043
1044 for (; gfn < end_gfn; gfn++) {
1045 unsigned long *rmap = &memslot->arch.rmap[gfn];
1046 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
1047 }
1048 }
1049
1050 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
1051 {
1052 unsigned long page;
1053
1054 for (page = 0; page < free->npages; page++) {
1055 unsigned long rmap, *rmapp = &free->arch.rmap[page];
1056 struct rmap_nested *cursor;
1057 struct llist_node *entry;
1058
1059 entry = llist_del_all((struct llist_head *) rmapp);
1060 for_each_nest_rmap_safe(cursor, entry, &rmap)
1061 kfree(cursor);
1062 }
1063 }
1064
1065 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
1066 struct kvm_nested_guest *gp,
1067 long gpa, int *shift_ret)
1068 {
1069 struct kvm *kvm = vcpu->kvm;
1070 bool ret = false;
1071 pte_t *ptep;
1072 int shift;
1073
1074 spin_lock(&kvm->mmu_lock);
1075 ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift);
1076 if (!shift)
1077 shift = PAGE_SHIFT;
1078 if (ptep && pte_present(*ptep)) {
1079 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1080 ret = true;
1081 }
1082 spin_unlock(&kvm->mmu_lock);
1083
1084 if (shift_ret)
1085 *shift_ret = shift;
1086 return ret;
1087 }
1088
1089 static inline int get_ric(unsigned int instr)
1090 {
1091 return (instr >> 18) & 0x3;
1092 }
1093
1094 static inline int get_prs(unsigned int instr)
1095 {
1096 return (instr >> 17) & 0x1;
1097 }
1098
1099 static inline int get_r(unsigned int instr)
1100 {
1101 return (instr >> 16) & 0x1;
1102 }
1103
1104 static inline int get_lpid(unsigned long r_val)
1105 {
1106 return r_val & 0xffffffff;
1107 }
1108
1109 static inline int get_is(unsigned long r_val)
1110 {
1111 return (r_val >> 10) & 0x3;
1112 }
1113
1114 static inline int get_ap(unsigned long r_val)
1115 {
1116 return (r_val >> 5) & 0x7;
1117 }
1118
1119 static inline long get_epn(unsigned long r_val)
1120 {
1121 return r_val >> 12;
1122 }
1123
1124 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid,
1125 int ap, long epn)
1126 {
1127 struct kvm *kvm = vcpu->kvm;
1128 struct kvm_nested_guest *gp;
1129 long npages;
1130 int shift, shadow_shift;
1131 unsigned long addr;
1132
1133 shift = ap_to_shift(ap);
1134 addr = epn << 12;
1135 if (shift < 0)
1136 /* Invalid ap encoding */
1137 return -EINVAL;
1138
1139 addr &= ~((1UL << shift) - 1);
1140 npages = 1UL << (shift - PAGE_SHIFT);
1141
1142 gp = kvmhv_get_nested(kvm, lpid, false);
1143 if (!gp) /* No such guest -> nothing to do */
1144 return 0;
1145 mutex_lock(&gp->tlb_lock);
1146
1147 /* There may be more than one host page backing this single guest pte */
1148 do {
1149 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift);
1150
1151 npages -= 1UL << (shadow_shift - PAGE_SHIFT);
1152 addr += 1UL << shadow_shift;
1153 } while (npages > 0);
1154
1155 mutex_unlock(&gp->tlb_lock);
1156 kvmhv_put_nested(gp);
1157 return 0;
1158 }
1159
1160 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu,
1161 struct kvm_nested_guest *gp, int ric)
1162 {
1163 struct kvm *kvm = vcpu->kvm;
1164
1165 mutex_lock(&gp->tlb_lock);
1166 switch (ric) {
1167 case 0:
1168 /* Invalidate TLB */
1169 spin_lock(&kvm->mmu_lock);
1170 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
1171 gp->shadow_lpid);
1172 kvmhv_flush_lpid(gp->shadow_lpid);
1173 spin_unlock(&kvm->mmu_lock);
1174 break;
1175 case 1:
1176 /*
1177 * Invalidate PWC
1178 * We don't cache this -> nothing to do
1179 */
1180 break;
1181 case 2:
1182 /* Invalidate TLB, PWC and caching of partition table entries */
1183 kvmhv_flush_nested(gp);
1184 break;
1185 default:
1186 break;
1187 }
1188 mutex_unlock(&gp->tlb_lock);
1189 }
1190
1191 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric)
1192 {
1193 struct kvm *kvm = vcpu->kvm;
1194 struct kvm_nested_guest *gp;
1195 int lpid;
1196
1197 spin_lock(&kvm->mmu_lock);
1198 idr_for_each_entry(&kvm->arch.kvm_nested_guest_idr, gp, lpid) {
1199 spin_unlock(&kvm->mmu_lock);
1200 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1201 spin_lock(&kvm->mmu_lock);
1202 }
1203 spin_unlock(&kvm->mmu_lock);
1204 }
1205
1206 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr,
1207 unsigned long rsval, unsigned long rbval)
1208 {
1209 struct kvm *kvm = vcpu->kvm;
1210 struct kvm_nested_guest *gp;
1211 int r, ric, prs, is, ap;
1212 int lpid;
1213 long epn;
1214 int ret = 0;
1215
1216 ric = get_ric(instr);
1217 prs = get_prs(instr);
1218 r = get_r(instr);
1219 lpid = get_lpid(rsval);
1220 is = get_is(rbval);
1221
1222 /*
1223 * These cases are invalid and are not handled:
1224 * r != 1 -> Only radix supported
1225 * prs == 1 -> Not HV privileged
1226 * ric == 3 -> No cluster bombs for radix
1227 * is == 1 -> Partition scoped translations not associated with pid
1228 * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA
1229 */
1230 if ((!r) || (prs) || (ric == 3) || (is == 1) ||
1231 ((!is) && (ric == 1 || ric == 2)))
1232 return -EINVAL;
1233
1234 switch (is) {
1235 case 0:
1236 /*
1237 * We know ric == 0
1238 * Invalidate TLB for a given target address
1239 */
1240 epn = get_epn(rbval);
1241 ap = get_ap(rbval);
1242 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn);
1243 break;
1244 case 2:
1245 /* Invalidate matching LPID */
1246 gp = kvmhv_get_nested(kvm, lpid, false);
1247 if (gp) {
1248 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1249 kvmhv_put_nested(gp);
1250 }
1251 break;
1252 case 3:
1253 /* Invalidate ALL LPIDs */
1254 kvmhv_emulate_tlbie_all_lpid(vcpu, ric);
1255 break;
1256 default:
1257 ret = -EINVAL;
1258 break;
1259 }
1260
1261 return ret;
1262 }
1263
1264 /*
1265 * This handles the H_TLB_INVALIDATE hcall.
1266 * Parameters are (r4) tlbie instruction code, (r5) rS contents,
1267 * (r6) rB contents.
1268 */
1269 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
1270 {
1271 int ret;
1272
1273 ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4),
1274 kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6));
1275 if (ret)
1276 return H_PARAMETER;
1277 return H_SUCCESS;
1278 }
1279
1280 static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
1281 unsigned long lpid, unsigned long ric)
1282 {
1283 struct kvm *kvm = vcpu->kvm;
1284 struct kvm_nested_guest *gp;
1285
1286 gp = kvmhv_get_nested(kvm, lpid, false);
1287 if (gp) {
1288 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1289 kvmhv_put_nested(gp);
1290 }
1291 return H_SUCCESS;
1292 }
1293
1294 /*
1295 * Number of pages above which we invalidate the entire LPID rather than
1296 * flush individual pages.
1297 */
1298 static unsigned long tlb_range_flush_page_ceiling __read_mostly = 33;
1299
1300 static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
1301 unsigned long lpid,
1302 unsigned long pg_sizes,
1303 unsigned long start,
1304 unsigned long end)
1305 {
1306 int ret = H_P4;
1307 unsigned long addr, nr_pages;
1308 struct mmu_psize_def *def;
1309 unsigned long psize, ap, page_size;
1310 bool flush_lpid;
1311
1312 for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1313 def = &mmu_psize_defs[psize];
1314 if (!(pg_sizes & def->h_rpt_pgsize))
1315 continue;
1316
1317 nr_pages = (end - start) >> def->shift;
1318 flush_lpid = nr_pages > tlb_range_flush_page_ceiling;
1319 if (flush_lpid)
1320 return do_tlb_invalidate_nested_all(vcpu, lpid,
1321 RIC_FLUSH_TLB);
1322 addr = start;
1323 ap = mmu_get_ap(psize);
1324 page_size = 1UL << def->shift;
1325 do {
1326 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
1327 get_epn(addr));
1328 if (ret)
1329 return H_P4;
1330 addr += page_size;
1331 } while (addr < end);
1332 }
1333 return ret;
1334 }
1335
1336 /*
1337 * Performs partition-scoped invalidations for nested guests
1338 * as part of H_RPT_INVALIDATE hcall.
1339 */
1340 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
1341 unsigned long type, unsigned long pg_sizes,
1342 unsigned long start, unsigned long end)
1343 {
1344 /*
1345 * If L2 lpid isn't valid, we need to return H_PARAMETER.
1346 *
1347 * However, nested KVM issues a L2 lpid flush call when creating
1348 * partition table entries for L2. This happens even before the
1349 * corresponding shadow lpid is created in HV which happens in
1350 * H_ENTER_NESTED call. Since we can't differentiate this case from
1351 * the invalid case, we ignore such flush requests and return success.
1352 */
1353 if (!__find_nested(vcpu->kvm, lpid))
1354 return H_SUCCESS;
1355
1356 /*
1357 * A flush all request can be handled by a full lpid flush only.
1358 */
1359 if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
1360 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
1361
1362 /*
1363 * We don't need to handle a PWC flush like process table here,
1364 * because intermediate partition scoped table in nested guest doesn't
1365 * really have PWC. Only level we have PWC is in L0 and for nested
1366 * invalidate at L0 we always do kvm_flush_lpid() which does
1367 * radix__flush_all_lpid(). For range invalidate at any level, we
1368 * are not removing the higher level page tables and hence there is
1369 * no PWC invalidate needed.
1370 *
1371 * if (type & H_RPTI_TYPE_PWC) {
1372 * ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
1373 * if (ret)
1374 * return H_P4;
1375 * }
1376 */
1377
1378 if (start == 0 && end == -1)
1379 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
1380
1381 if (type & H_RPTI_TYPE_TLB)
1382 return do_tlb_invalidate_nested_tlb(vcpu, lpid, pg_sizes,
1383 start, end);
1384 return H_SUCCESS;
1385 }
1386
1387 /* Used to convert a nested guest real address to a L1 guest real address */
1388 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
1389 struct kvm_nested_guest *gp,
1390 unsigned long n_gpa, unsigned long dsisr,
1391 struct kvmppc_pte *gpte_p)
1392 {
1393 u64 fault_addr, flags = dsisr & DSISR_ISSTORE;
1394 int ret;
1395
1396 ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr,
1397 &fault_addr);
1398
1399 if (ret) {
1400 /* We didn't find a pte */
1401 if (ret == -EINVAL) {
1402 /* Unsupported mmu config */
1403 flags |= DSISR_UNSUPP_MMU;
1404 } else if (ret == -ENOENT) {
1405 /* No translation found */
1406 flags |= DSISR_NOHPTE;
1407 } else if (ret == -EFAULT) {
1408 /* Couldn't access L1 real address */
1409 flags |= DSISR_PRTABLE_FAULT;
1410 vcpu->arch.fault_gpa = fault_addr;
1411 } else {
1412 /* Unknown error */
1413 return ret;
1414 }
1415 goto forward_to_l1;
1416 } else {
1417 /* We found a pte -> check permissions */
1418 if (dsisr & DSISR_ISSTORE) {
1419 /* Can we write? */
1420 if (!gpte_p->may_write) {
1421 flags |= DSISR_PROTFAULT;
1422 goto forward_to_l1;
1423 }
1424 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1425 /* Can we execute? */
1426 if (!gpte_p->may_execute) {
1427 flags |= SRR1_ISI_N_G_OR_CIP;
1428 goto forward_to_l1;
1429 }
1430 } else {
1431 /* Can we read? */
1432 if (!gpte_p->may_read && !gpte_p->may_write) {
1433 flags |= DSISR_PROTFAULT;
1434 goto forward_to_l1;
1435 }
1436 }
1437 }
1438
1439 return 0;
1440
1441 forward_to_l1:
1442 vcpu->arch.fault_dsisr = flags;
1443 if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1444 vcpu->arch.shregs.msr &= SRR1_MSR_BITS;
1445 vcpu->arch.shregs.msr |= flags;
1446 }
1447 return RESUME_HOST;
1448 }
1449
1450 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
1451 struct kvm_nested_guest *gp,
1452 unsigned long n_gpa,
1453 struct kvmppc_pte gpte,
1454 unsigned long dsisr)
1455 {
1456 struct kvm *kvm = vcpu->kvm;
1457 bool writing = !!(dsisr & DSISR_ISSTORE);
1458 u64 pgflags;
1459 long ret;
1460
1461 /* Are the rc bits set in the L1 partition scoped pte? */
1462 pgflags = _PAGE_ACCESSED;
1463 if (writing)
1464 pgflags |= _PAGE_DIRTY;
1465 if (pgflags & ~gpte.rc)
1466 return RESUME_HOST;
1467
1468 spin_lock(&kvm->mmu_lock);
1469 /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
1470 ret = kvmppc_hv_handle_set_rc(kvm, false, writing,
1471 gpte.raddr, kvm->arch.lpid);
1472 if (!ret) {
1473 ret = -EINVAL;
1474 goto out_unlock;
1475 }
1476
1477 /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
1478 ret = kvmppc_hv_handle_set_rc(kvm, true, writing,
1479 n_gpa, gp->l1_lpid);
1480 if (!ret)
1481 ret = -EINVAL;
1482 else
1483 ret = 0;
1484
1485 out_unlock:
1486 spin_unlock(&kvm->mmu_lock);
1487 return ret;
1488 }
1489
1490 static inline int kvmppc_radix_level_to_shift(int level)
1491 {
1492 switch (level) {
1493 case 2:
1494 return PUD_SHIFT;
1495 case 1:
1496 return PMD_SHIFT;
1497 default:
1498 return PAGE_SHIFT;
1499 }
1500 }
1501
1502 static inline int kvmppc_radix_shift_to_level(int shift)
1503 {
1504 if (shift == PUD_SHIFT)
1505 return 2;
1506 if (shift == PMD_SHIFT)
1507 return 1;
1508 if (shift == PAGE_SHIFT)
1509 return 0;
1510 WARN_ON_ONCE(1);
1511 return 0;
1512 }
1513
1514 /* called with gp->tlb_lock held */
1515 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
1516 struct kvm_nested_guest *gp)
1517 {
1518 struct kvm *kvm = vcpu->kvm;
1519 struct kvm_memory_slot *memslot;
1520 struct rmap_nested *n_rmap;
1521 struct kvmppc_pte gpte;
1522 pte_t pte, *pte_p;
1523 unsigned long mmu_seq;
1524 unsigned long dsisr = vcpu->arch.fault_dsisr;
1525 unsigned long ea = vcpu->arch.fault_dar;
1526 unsigned long *rmapp;
1527 unsigned long n_gpa, gpa, gfn, perm = 0UL;
1528 unsigned int shift, l1_shift, level;
1529 bool writing = !!(dsisr & DSISR_ISSTORE);
1530 bool kvm_ro = false;
1531 long int ret;
1532
1533 if (!gp->l1_gr_to_hr) {
1534 kvmhv_update_ptbl_cache(gp);
1535 if (!gp->l1_gr_to_hr)
1536 return RESUME_HOST;
1537 }
1538
1539 /* Convert the nested guest real address into a L1 guest real address */
1540
1541 n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL;
1542 if (!(dsisr & DSISR_PRTABLE_FAULT))
1543 n_gpa |= ea & 0xFFF;
1544 ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte);
1545
1546 /*
1547 * If the hardware found a translation but we don't now have a usable
1548 * translation in the l1 partition-scoped tree, remove the shadow pte
1549 * and let the guest retry.
1550 */
1551 if (ret == RESUME_HOST &&
1552 (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G |
1553 DSISR_BAD_COPYPASTE)))
1554 goto inval;
1555 if (ret)
1556 return ret;
1557
1558 /* Failed to set the reference/change bits */
1559 if (dsisr & DSISR_SET_RC) {
1560 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr);
1561 if (ret == RESUME_HOST)
1562 return ret;
1563 if (ret)
1564 goto inval;
1565 dsisr &= ~DSISR_SET_RC;
1566 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
1567 DSISR_PROTFAULT)))
1568 return RESUME_GUEST;
1569 }
1570
1571 /*
1572 * We took an HISI or HDSI while we were running a nested guest which
1573 * means we have no partition scoped translation for that. This means
1574 * we need to insert a pte for the mapping into our shadow_pgtable.
1575 */
1576
1577 l1_shift = gpte.page_shift;
1578 if (l1_shift < PAGE_SHIFT) {
1579 /* We don't support l1 using a page size smaller than our own */
1580 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n",
1581 l1_shift, PAGE_SHIFT);
1582 return -EINVAL;
1583 }
1584 gpa = gpte.raddr;
1585 gfn = gpa >> PAGE_SHIFT;
1586
1587 /* 1. Get the corresponding host memslot */
1588
1589 memslot = gfn_to_memslot(kvm, gfn);
1590 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
1591 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) {
1592 /* unusual error -> reflect to the guest as a DSI */
1593 kvmppc_core_queue_data_storage(vcpu,
1594 kvmppc_get_msr(vcpu) & SRR1_PREFIXED,
1595 ea, dsisr);
1596 return RESUME_GUEST;
1597 }
1598
1599 /* passthrough of emulated MMIO case */
1600 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing);
1601 }
1602 if (memslot->flags & KVM_MEM_READONLY) {
1603 if (writing) {
1604 /* Give the guest a DSI */
1605 kvmppc_core_queue_data_storage(vcpu,
1606 kvmppc_get_msr(vcpu) & SRR1_PREFIXED,
1607 ea, DSISR_ISSTORE | DSISR_PROTFAULT);
1608 return RESUME_GUEST;
1609 }
1610 kvm_ro = true;
1611 }
1612
1613 /* 2. Find the host pte for this L1 guest real address */
1614
1615 /* Used to check for invalidations in progress */
1616 mmu_seq = kvm->mmu_invalidate_seq;
1617 smp_rmb();
1618
1619 /* See if can find translation in our partition scoped tables for L1 */
1620 pte = __pte(0);
1621 spin_lock(&kvm->mmu_lock);
1622 pte_p = find_kvm_secondary_pte(kvm, gpa, &shift);
1623 if (!shift)
1624 shift = PAGE_SHIFT;
1625 if (pte_p)
1626 pte = *pte_p;
1627 spin_unlock(&kvm->mmu_lock);
1628
1629 if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) {
1630 /* No suitable pte found -> try to insert a mapping */
1631 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot,
1632 writing, kvm_ro, &pte, &level);
1633 if (ret == -EAGAIN)
1634 return RESUME_GUEST;
1635 else if (ret)
1636 return ret;
1637 shift = kvmppc_radix_level_to_shift(level);
1638 }
1639 /* Align gfn to the start of the page */
1640 gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
1641
1642 /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
1643
1644 /* The permissions is the combination of the host and l1 guest ptes */
1645 perm |= gpte.may_read ? 0UL : _PAGE_READ;
1646 perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
1647 perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
1648 /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
1649 perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
1650 perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
1651 pte = __pte(pte_val(pte) & ~perm);
1652
1653 /* What size pte can we insert? */
1654 if (shift > l1_shift) {
1655 u64 mask;
1656 unsigned int actual_shift = PAGE_SHIFT;
1657 if (PMD_SHIFT < l1_shift)
1658 actual_shift = PMD_SHIFT;
1659 mask = (1UL << shift) - (1UL << actual_shift);
1660 pte = __pte(pte_val(pte) | (gpa & mask));
1661 shift = actual_shift;
1662 }
1663 level = kvmppc_radix_shift_to_level(shift);
1664 n_gpa &= ~((1UL << shift) - 1);
1665
1666 /* 4. Insert the pte into our shadow_pgtable */
1667
1668 n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
1669 if (!n_rmap)
1670 return RESUME_GUEST; /* Let the guest try again */
1671 n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
1672 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
1673 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1674 ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
1675 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
1676 kfree(n_rmap);
1677 if (ret == -EAGAIN)
1678 ret = RESUME_GUEST; /* Let the guest try again */
1679
1680 return ret;
1681
1682 inval:
1683 kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL);
1684 return RESUME_GUEST;
1685 }
1686
1687 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
1688 {
1689 struct kvm_nested_guest *gp = vcpu->arch.nested;
1690 long int ret;
1691
1692 mutex_lock(&gp->tlb_lock);
1693 ret = __kvmhv_nested_page_fault(vcpu, gp);
1694 mutex_unlock(&gp->tlb_lock);
1695 return ret;
1696 }
1697
1698 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid)
1699 {
1700 int ret = lpid + 1;
1701
1702 spin_lock(&kvm->mmu_lock);
1703 if (!idr_get_next(&kvm->arch.kvm_nested_guest_idr, &ret))
1704 ret = -1;
1705 spin_unlock(&kvm->mmu_lock);
1706
1707 return ret;
1708 }
1709
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