1 // SPDX-License-Identifier: GPL-2.0
3 * kvm nested virtualization support for s390x
5 * Copyright IBM Corp. 2016, 2018
7 * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com>
9 #include <linux/vmalloc.h>
10 #include <linux/kvm_host.h>
11 #include <linux/bug.h>
12 #include <linux/list.h>
13 #include <linux/bitmap.h>
14 #include <linux/sched/signal.h>
17 #include <asm/mmu_context.h>
25 struct kvm_s390_sie_block scb_s; /* 0x0000 */
27 * the backup info for machine check. ensure it's at
28 * the same offset as that in struct sie_page!
30 struct mcck_volatile_info mcck_info; /* 0x0200 */
32 * The pinned original scb. Be aware that other VCPUs can modify
33 * it while we read from it. Values that are used for conditions or
34 * are reused conditionally, should be accessed via READ_ONCE.
36 struct kvm_s390_sie_block *scb_o; /* 0x0218 */
37 /* the shadow gmap in use by the vsie_page */
38 struct gmap *gmap; /* 0x0220 */
39 /* address of the last reported fault to guest2 */
40 unsigned long fault_addr; /* 0x0228 */
41 /* calculated guest addresses of satellite control blocks */
42 gpa_t sca_gpa; /* 0x0230 */
43 gpa_t itdba_gpa; /* 0x0238 */
44 gpa_t gvrd_gpa; /* 0x0240 */
45 gpa_t riccbd_gpa; /* 0x0248 */
46 gpa_t sdnx_gpa; /* 0x0250 */
47 __u8 reserved[0x0700 - 0x0258]; /* 0x0258 */
48 struct kvm_s390_crypto_cb crycb; /* 0x0700 */
49 __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */
52 /* trigger a validity icpt for the given scb */
53 static int set_validity_icpt(struct kvm_s390_sie_block *scb,
57 scb->ipb = ((__u32) reason_code) << 16;
58 scb->icptcode = ICPT_VALIDITY;
62 /* mark the prefix as unmapped, this will block the VSIE */
63 static void prefix_unmapped(struct vsie_page *vsie_page)
65 atomic_or(PROG_REQUEST, &vsie_page->scb_s.prog20);
68 /* mark the prefix as unmapped and wait until the VSIE has been left */
69 static void prefix_unmapped_sync(struct vsie_page *vsie_page)
71 prefix_unmapped(vsie_page);
72 if (vsie_page->scb_s.prog0c & PROG_IN_SIE)
73 atomic_or(CPUSTAT_STOP_INT, &vsie_page->scb_s.cpuflags);
74 while (vsie_page->scb_s.prog0c & PROG_IN_SIE)
78 /* mark the prefix as mapped, this will allow the VSIE to run */
79 static void prefix_mapped(struct vsie_page *vsie_page)
81 atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20);
84 /* test if the prefix is mapped into the gmap shadow */
85 static int prefix_is_mapped(struct vsie_page *vsie_page)
87 return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST);
90 /* copy the updated intervention request bits into the shadow scb */
91 static void update_intervention_requests(struct vsie_page *vsie_page)
93 const int bits = CPUSTAT_STOP_INT | CPUSTAT_IO_INT | CPUSTAT_EXT_INT;
96 cpuflags = atomic_read(&vsie_page->scb_o->cpuflags);
97 atomic_andnot(bits, &vsie_page->scb_s.cpuflags);
98 atomic_or(cpuflags & bits, &vsie_page->scb_s.cpuflags);
101 /* shadow (filter and validate) the cpuflags */
102 static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
104 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
105 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
106 int newflags, cpuflags = atomic_read(&scb_o->cpuflags);
108 /* we don't allow ESA/390 guests */
109 if (!(cpuflags & CPUSTAT_ZARCH))
110 return set_validity_icpt(scb_s, 0x0001U);
112 if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS))
113 return set_validity_icpt(scb_s, 0x0001U);
114 else if (cpuflags & (CPUSTAT_SLSV | CPUSTAT_SLSR))
115 return set_validity_icpt(scb_s, 0x0007U);
117 /* intervention requests will be set later */
118 newflags = CPUSTAT_ZARCH;
119 if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8))
120 newflags |= CPUSTAT_GED;
121 if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) {
122 if (cpuflags & CPUSTAT_GED)
123 return set_validity_icpt(scb_s, 0x0001U);
124 newflags |= CPUSTAT_GED2;
126 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE))
127 newflags |= cpuflags & CPUSTAT_P;
128 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS))
129 newflags |= cpuflags & CPUSTAT_SM;
130 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS))
131 newflags |= cpuflags & CPUSTAT_IBS;
132 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_KSS))
133 newflags |= cpuflags & CPUSTAT_KSS;
135 atomic_set(&scb_s->cpuflags, newflags);
140 * Create a shadow copy of the crycb block and setup key wrapping, if
141 * requested for guest 3 and enabled for guest 2.
143 * We only accept format-1 (no AP in g2), but convert it into format-2
144 * There is nothing to do for format-0.
146 * Returns: - 0 if shadowed or nothing to do
147 * - > 0 if control has to be given to guest 2
149 static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
151 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
152 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
153 const uint32_t crycbd_o = READ_ONCE(scb_o->crycbd);
154 const u32 crycb_addr = crycbd_o & 0x7ffffff8U;
155 unsigned long *b1, *b2;
159 if (!(crycbd_o & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1))
161 /* format-1 is supported with message-security-assist extension 3 */
162 if (!test_kvm_facility(vcpu->kvm, 76))
164 /* we may only allow it if enabled for guest 2 */
165 ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 &
166 (ECB3_AES | ECB3_DEA);
170 if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK))
171 return set_validity_icpt(scb_s, 0x003CU);
172 else if (!crycb_addr)
173 return set_validity_icpt(scb_s, 0x0039U);
175 /* copy only the wrapping keys */
176 if (read_guest_real(vcpu, crycb_addr + 72,
177 vsie_page->crycb.dea_wrapping_key_mask, 56))
178 return set_validity_icpt(scb_s, 0x0035U);
180 scb_s->ecb3 |= ecb3_flags;
181 scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 |
184 /* xor both blocks in one run */
185 b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask;
186 b2 = (unsigned long *)
187 vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask;
188 /* as 56%8 == 0, bitmap_xor won't overwrite any data */
189 bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56);
193 /* shadow (round up/down) the ibc to avoid validity icpt */
194 static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
196 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
197 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
198 /* READ_ONCE does not work on bitfields - use a temporary variable */
199 const uint32_t __new_ibc = scb_o->ibc;
200 const uint32_t new_ibc = READ_ONCE(__new_ibc) & 0x0fffU;
201 __u64 min_ibc = (sclp.ibc >> 16) & 0x0fffU;
204 /* ibc installed in g2 and requested for g3 */
205 if (vcpu->kvm->arch.model.ibc && new_ibc) {
206 scb_s->ibc = new_ibc;
207 /* takte care of the minimum ibc level of the machine */
208 if (scb_s->ibc < min_ibc)
209 scb_s->ibc = min_ibc;
210 /* take care of the maximum ibc level set for the guest */
211 if (scb_s->ibc > vcpu->kvm->arch.model.ibc)
212 scb_s->ibc = vcpu->kvm->arch.model.ibc;
216 /* unshadow the scb, copying parameters back to the real scb */
217 static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
219 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
220 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
223 scb_o->icptcode = scb_s->icptcode;
224 scb_o->icptstatus = scb_s->icptstatus;
225 scb_o->ipa = scb_s->ipa;
226 scb_o->ipb = scb_s->ipb;
227 scb_o->gbea = scb_s->gbea;
230 scb_o->cputm = scb_s->cputm;
231 scb_o->ckc = scb_s->ckc;
232 scb_o->todpr = scb_s->todpr;
235 scb_o->gpsw = scb_s->gpsw;
236 scb_o->gg14 = scb_s->gg14;
237 scb_o->gg15 = scb_s->gg15;
238 memcpy(scb_o->gcr, scb_s->gcr, 128);
239 scb_o->pp = scb_s->pp;
241 /* branch prediction */
242 if (test_kvm_facility(vcpu->kvm, 82)) {
243 scb_o->fpf &= ~FPF_BPBC;
244 scb_o->fpf |= scb_s->fpf & FPF_BPBC;
247 /* interrupt intercept */
248 switch (scb_s->icptcode) {
252 memcpy((void *)((u64)scb_o + 0xc0),
253 (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0);
257 memcpy((void *)((u64)scb_o + 0xc0),
258 (void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0);
262 if (scb_s->ihcpu != 0xffffU)
263 scb_o->ihcpu = scb_s->ihcpu;
267 * Setup the shadow scb by copying and checking the relevant parts of the g2
270 * Returns: - 0 if the scb has been shadowed
271 * - > 0 if control has to be given to guest 2
273 static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
275 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
276 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
277 /* READ_ONCE does not work on bitfields - use a temporary variable */
278 const uint32_t __new_prefix = scb_o->prefix;
279 const uint32_t new_prefix = READ_ONCE(__new_prefix);
280 const bool wants_tx = READ_ONCE(scb_o->ecb) & ECB_TE;
281 bool had_tx = scb_s->ecb & ECB_TE;
282 unsigned long new_mso = 0;
285 /* make sure we don't have any leftovers when reusing the scb */
295 rc = prepare_cpuflags(vcpu, vsie_page);
300 scb_s->cputm = scb_o->cputm;
301 scb_s->ckc = scb_o->ckc;
302 scb_s->todpr = scb_o->todpr;
303 scb_s->epoch = scb_o->epoch;
306 scb_s->gpsw = scb_o->gpsw;
307 scb_s->gg14 = scb_o->gg14;
308 scb_s->gg15 = scb_o->gg15;
309 memcpy(scb_s->gcr, scb_o->gcr, 128);
310 scb_s->pp = scb_o->pp;
312 /* interception / execution handling */
313 scb_s->gbea = scb_o->gbea;
314 scb_s->lctl = scb_o->lctl;
315 scb_s->svcc = scb_o->svcc;
316 scb_s->ictl = scb_o->ictl;
318 * SKEY handling functions can't deal with false setting of PTE invalid
319 * bits. Therefore we cannot provide interpretation and would later
320 * have to provide own emulation handlers.
322 if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_KSS))
323 scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
325 scb_s->icpua = scb_o->icpua;
327 if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM))
328 new_mso = READ_ONCE(scb_o->mso) & 0xfffffffffff00000UL;
329 /* if the hva of the prefix changes, we have to remap the prefix */
330 if (scb_s->mso != new_mso || scb_s->prefix != new_prefix)
331 prefix_unmapped(vsie_page);
332 /* SIE will do mso/msl validity and exception checks for us */
333 scb_s->msl = scb_o->msl & 0xfffffffffff00000UL;
334 scb_s->mso = new_mso;
335 scb_s->prefix = new_prefix;
337 /* We have to definetly flush the tlb if this scb never ran */
338 if (scb_s->ihcpu != 0xffffU)
339 scb_s->ihcpu = scb_o->ihcpu;
341 /* MVPG and Protection Exception Interpretation are always available */
342 scb_s->eca |= scb_o->eca & (ECA_MVPGI | ECA_PROTEXCI);
343 /* Host-protection-interruption introduced with ESOP */
344 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP))
345 scb_s->ecb |= scb_o->ecb & ECB_HOSTPROTINT;
346 /* transactional execution */
347 if (test_kvm_facility(vcpu->kvm, 73) && wants_tx) {
348 /* remap the prefix is tx is toggled on */
350 prefix_unmapped(vsie_page);
351 scb_s->ecb |= ECB_TE;
353 /* branch prediction */
354 if (test_kvm_facility(vcpu->kvm, 82))
355 scb_s->fpf |= scb_o->fpf & FPF_BPBC;
357 if (test_kvm_facility(vcpu->kvm, 129)) {
358 scb_s->eca |= scb_o->eca & ECA_VX;
359 scb_s->ecd |= scb_o->ecd & ECD_HOSTREGMGMT;
361 /* Run-time-Instrumentation */
362 if (test_kvm_facility(vcpu->kvm, 64))
363 scb_s->ecb3 |= scb_o->ecb3 & ECB3_RI;
364 /* Instruction Execution Prevention */
365 if (test_kvm_facility(vcpu->kvm, 130))
366 scb_s->ecb2 |= scb_o->ecb2 & ECB2_IEP;
367 /* Guarded Storage */
368 if (test_kvm_facility(vcpu->kvm, 133)) {
369 scb_s->ecb |= scb_o->ecb & ECB_GS;
370 scb_s->ecd |= scb_o->ecd & ECD_HOSTREGMGMT;
372 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF))
373 scb_s->eca |= scb_o->eca & ECA_SII;
374 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB))
375 scb_s->eca |= scb_o->eca & ECA_IB;
376 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI))
377 scb_s->eca |= scb_o->eca & ECA_CEI;
378 /* Epoch Extension */
379 if (test_kvm_facility(vcpu->kvm, 139))
380 scb_s->ecd |= scb_o->ecd & ECD_MEF;
383 if (test_kvm_facility(vcpu->kvm, 156))
384 scb_s->ecd |= scb_o->ecd & ECD_ETOKENF;
386 prepare_ibc(vcpu, vsie_page);
387 rc = shadow_crycb(vcpu, vsie_page);
390 unshadow_scb(vcpu, vsie_page);
394 void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
397 struct kvm *kvm = gmap->private;
398 struct vsie_page *cur;
399 unsigned long prefix;
403 if (!gmap_is_shadow(gmap))
405 if (start >= 1UL << 31)
406 /* We are only interested in prefix pages */
410 * Only new shadow blocks are added to the list during runtime,
411 * therefore we can safely reference them all the time.
413 for (i = 0; i < kvm->arch.vsie.page_count; i++) {
414 page = READ_ONCE(kvm->arch.vsie.pages[i]);
417 cur = page_to_virt(page);
418 if (READ_ONCE(cur->gmap) != gmap)
420 prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT;
421 /* with mso/msl, the prefix lies at an offset */
422 prefix += cur->scb_s.mso;
423 if (prefix <= end && start <= prefix + 2 * PAGE_SIZE - 1)
424 prefix_unmapped_sync(cur);
429 * Map the first prefix page and if tx is enabled also the second prefix page.
431 * The prefix will be protected, a gmap notifier will inform about unmaps.
432 * The shadow scb must not be executed until the prefix is remapped, this is
433 * guaranteed by properly handling PROG_REQUEST.
435 * Returns: - 0 on if successfully mapped or already mapped
436 * - > 0 if control has to be given to guest 2
437 * - -EAGAIN if the caller can retry immediately
438 * - -ENOMEM if out of memory
440 static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
442 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
443 u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT;
446 if (prefix_is_mapped(vsie_page))
449 /* mark it as mapped so we can catch any concurrent unmappers */
450 prefix_mapped(vsie_page);
452 /* with mso/msl, the prefix lies at offset *mso* */
453 prefix += scb_s->mso;
455 rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix);
456 if (!rc && (scb_s->ecb & ECB_TE))
457 rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
460 * We don't have to mprotect, we will be called for all unshadows.
461 * SIE will detect if protection applies and trigger a validity.
464 prefix_unmapped(vsie_page);
465 if (rc > 0 || rc == -EFAULT)
466 rc = set_validity_icpt(scb_s, 0x0037U);
471 * Pin the guest page given by gpa and set hpa to the pinned host address.
472 * Will always be pinned writable.
474 * Returns: - 0 on success
475 * - -EINVAL if the gpa is not valid guest storage
477 static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa)
481 page = gfn_to_page(kvm, gpa_to_gfn(gpa));
482 if (is_error_page(page))
484 *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK);
488 /* Unpins a page previously pinned via pin_guest_page, marking it as dirty. */
489 static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa)
491 kvm_release_pfn_dirty(hpa >> PAGE_SHIFT);
492 /* mark the page always as dirty for migration */
493 mark_page_dirty(kvm, gpa_to_gfn(gpa));
496 /* unpin all blocks previously pinned by pin_blocks(), marking them dirty */
497 static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
499 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
502 hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol;
504 unpin_guest_page(vcpu->kvm, vsie_page->sca_gpa, hpa);
505 vsie_page->sca_gpa = 0;
512 unpin_guest_page(vcpu->kvm, vsie_page->itdba_gpa, hpa);
513 vsie_page->itdba_gpa = 0;
519 unpin_guest_page(vcpu->kvm, vsie_page->gvrd_gpa, hpa);
520 vsie_page->gvrd_gpa = 0;
526 unpin_guest_page(vcpu->kvm, vsie_page->riccbd_gpa, hpa);
527 vsie_page->riccbd_gpa = 0;
533 unpin_guest_page(vcpu->kvm, vsie_page->sdnx_gpa, hpa);
534 vsie_page->sdnx_gpa = 0;
540 * Instead of shadowing some blocks, we can simply forward them because the
541 * addresses in the scb are 64 bit long.
543 * This works as long as the data lies in one page. If blocks ever exceed one
544 * page, we have to fall back to shadowing.
546 * As we reuse the sca, the vcpu pointers contained in it are invalid. We must
547 * therefore not enable any facilities that access these pointers (e.g. SIGPIF).
549 * Returns: - 0 if all blocks were pinned.
550 * - > 0 if control has to be given to guest 2
551 * - -ENOMEM if out of memory
553 static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
555 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
556 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
561 gpa = READ_ONCE(scb_o->scaol) & ~0xfUL;
562 if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO))
563 gpa |= (u64) READ_ONCE(scb_o->scaoh) << 32;
565 if (gpa < 2 * PAGE_SIZE)
566 rc = set_validity_icpt(scb_s, 0x0038U);
567 else if ((gpa & ~0x1fffUL) == kvm_s390_get_prefix(vcpu))
568 rc = set_validity_icpt(scb_s, 0x0011U);
569 else if ((gpa & PAGE_MASK) !=
570 ((gpa + sizeof(struct bsca_block) - 1) & PAGE_MASK))
571 rc = set_validity_icpt(scb_s, 0x003bU);
573 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
575 rc = set_validity_icpt(scb_s, 0x0034U);
579 vsie_page->sca_gpa = gpa;
580 scb_s->scaoh = (u32)((u64)hpa >> 32);
581 scb_s->scaol = (u32)(u64)hpa;
584 gpa = READ_ONCE(scb_o->itdba) & ~0xffUL;
585 if (gpa && (scb_s->ecb & ECB_TE)) {
586 if (gpa < 2 * PAGE_SIZE) {
587 rc = set_validity_icpt(scb_s, 0x0080U);
590 /* 256 bytes cannot cross page boundaries */
591 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
593 rc = set_validity_icpt(scb_s, 0x0080U);
596 vsie_page->itdba_gpa = gpa;
600 gpa = READ_ONCE(scb_o->gvrd) & ~0x1ffUL;
601 if (gpa && (scb_s->eca & ECA_VX) && !(scb_s->ecd & ECD_HOSTREGMGMT)) {
602 if (gpa < 2 * PAGE_SIZE) {
603 rc = set_validity_icpt(scb_s, 0x1310U);
607 * 512 bytes vector registers cannot cross page boundaries
608 * if this block gets bigger, we have to shadow it.
610 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
612 rc = set_validity_icpt(scb_s, 0x1310U);
615 vsie_page->gvrd_gpa = gpa;
619 gpa = READ_ONCE(scb_o->riccbd) & ~0x3fUL;
620 if (gpa && (scb_s->ecb3 & ECB3_RI)) {
621 if (gpa < 2 * PAGE_SIZE) {
622 rc = set_validity_icpt(scb_s, 0x0043U);
625 /* 64 bytes cannot cross page boundaries */
626 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
628 rc = set_validity_icpt(scb_s, 0x0043U);
631 /* Validity 0x0044 will be checked by SIE */
632 vsie_page->riccbd_gpa = gpa;
635 if (((scb_s->ecb & ECB_GS) && !(scb_s->ecd & ECD_HOSTREGMGMT)) ||
636 (scb_s->ecd & ECD_ETOKENF)) {
639 gpa = READ_ONCE(scb_o->sdnxo) & ~0xfUL;
640 sdnxc = READ_ONCE(scb_o->sdnxo) & 0xfUL;
641 if (!gpa || gpa < 2 * PAGE_SIZE) {
642 rc = set_validity_icpt(scb_s, 0x10b0U);
645 if (sdnxc < 6 || sdnxc > 12) {
646 rc = set_validity_icpt(scb_s, 0x10b1U);
649 if (gpa & ((1 << sdnxc) - 1)) {
650 rc = set_validity_icpt(scb_s, 0x10b2U);
653 /* Due to alignment rules (checked above) this cannot
654 * cross page boundaries
656 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
658 rc = set_validity_icpt(scb_s, 0x10b0U);
661 vsie_page->sdnx_gpa = gpa;
662 scb_s->sdnxo = hpa | sdnxc;
666 unpin_blocks(vcpu, vsie_page);
670 /* unpin the scb provided by guest 2, marking it as dirty */
671 static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
674 hpa_t hpa = (hpa_t) vsie_page->scb_o;
677 unpin_guest_page(vcpu->kvm, gpa, hpa);
678 vsie_page->scb_o = NULL;
682 * Pin the scb at gpa provided by guest 2 at vsie_page->scb_o.
684 * Returns: - 0 if the scb was pinned.
685 * - > 0 if control has to be given to guest 2
687 static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
693 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
695 rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
699 vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa;
704 * Inject a fault into guest 2.
706 * Returns: - > 0 if control has to be given to guest 2
707 * < 0 if an error occurred during injection.
709 static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr,
712 struct kvm_s390_pgm_info pgm = {
715 /* 0-51: virtual address */
716 (vaddr & 0xfffffffffffff000UL) |
717 /* 52-53: store / fetch */
718 (((unsigned int) !write_flag) + 1) << 10,
719 /* 62-63: asce id (alway primary == 0) */
720 .exc_access_id = 0, /* always primary */
721 .op_access_id = 0, /* not MVPG */
725 if (code == PGM_PROTECTION)
726 pgm.trans_exc_code |= 0x4UL;
728 rc = kvm_s390_inject_prog_irq(vcpu, &pgm);
733 * Handle a fault during vsie execution on a gmap shadow.
735 * Returns: - 0 if the fault was resolved
736 * - > 0 if control has to be given to guest 2
737 * - < 0 if an error occurred
739 static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
743 if (current->thread.gmap_int_code == PGM_PROTECTION)
744 /* we can directly forward all protection exceptions */
745 return inject_fault(vcpu, PGM_PROTECTION,
746 current->thread.gmap_addr, 1);
748 rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
749 current->thread.gmap_addr);
751 rc = inject_fault(vcpu, rc,
752 current->thread.gmap_addr,
753 current->thread.gmap_write_flag);
755 vsie_page->fault_addr = current->thread.gmap_addr;
761 * Retry the previous fault that required guest 2 intervention. This avoids
762 * one superfluous SIE re-entry and direct exit.
764 * Will ignore any errors. The next SIE fault will do proper fault handling.
766 static void handle_last_fault(struct kvm_vcpu *vcpu,
767 struct vsie_page *vsie_page)
769 if (vsie_page->fault_addr)
770 kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
771 vsie_page->fault_addr);
772 vsie_page->fault_addr = 0;
775 static inline void clear_vsie_icpt(struct vsie_page *vsie_page)
777 vsie_page->scb_s.icptcode = 0;
780 /* rewind the psw and clear the vsie icpt, so we can retry execution */
781 static void retry_vsie_icpt(struct vsie_page *vsie_page)
783 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
784 int ilen = insn_length(scb_s->ipa >> 8);
786 /* take care of EXECUTE instructions */
787 if (scb_s->icptstatus & 1) {
788 ilen = (scb_s->icptstatus >> 4) & 0x6;
792 scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, ilen);
793 clear_vsie_icpt(vsie_page);
797 * Try to shadow + enable the guest 2 provided facility list.
798 * Retry instruction execution if enabled for and provided by guest 2.
800 * Returns: - 0 if handled (retry or guest 2 icpt)
801 * - > 0 if control has to be given to guest 2
803 static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
805 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
806 __u32 fac = READ_ONCE(vsie_page->scb_o->fac) & 0x7ffffff8U;
808 if (fac && test_kvm_facility(vcpu->kvm, 7)) {
809 retry_vsie_icpt(vsie_page);
810 if (read_guest_real(vcpu, fac, &vsie_page->fac,
811 sizeof(vsie_page->fac)))
812 return set_validity_icpt(scb_s, 0x1090U);
813 scb_s->fac = (__u32)(__u64) &vsie_page->fac;
819 * Run the vsie on a shadow scb and a shadow gmap, without any further
820 * sanity checks, handling SIE faults.
822 * Returns: - 0 everything went fine
823 * - > 0 if control has to be given to guest 2
824 * - < 0 if an error occurred
826 static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
827 __releases(vcpu->kvm->srcu)
828 __acquires(vcpu->kvm->srcu)
830 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
831 struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
832 int guest_bp_isolation;
835 handle_last_fault(vcpu, vsie_page);
839 if (test_cpu_flag(CIF_MCCK_PENDING))
842 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
844 /* save current guest state of bp isolation override */
845 guest_bp_isolation = test_thread_flag(TIF_ISOLATE_BP_GUEST);
848 * The guest is running with BPBC, so we have to force it on for our
849 * nested guest. This is done by enabling BPBC globally, so the BPBC
850 * control in the SCB (which the nested guest can modify) is simply
853 if (test_kvm_facility(vcpu->kvm, 82) &&
854 vcpu->arch.sie_block->fpf & FPF_BPBC)
855 set_thread_flag(TIF_ISOLATE_BP_GUEST);
858 guest_enter_irqoff();
861 rc = sie64a(scb_s, vcpu->run->s.regs.gprs);
867 /* restore guest state for bp isolation override */
868 if (!guest_bp_isolation)
869 clear_thread_flag(TIF_ISOLATE_BP_GUEST);
871 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
874 VCPU_EVENT(vcpu, 3, "%s", "machine check");
875 kvm_s390_reinject_machine_check(vcpu, &vsie_page->mcck_info);
880 rc = 0; /* we could still have an icpt */
881 else if (rc == -EFAULT)
882 return handle_fault(vcpu, vsie_page);
884 switch (scb_s->icptcode) {
886 if (scb_s->ipa == 0xb2b0)
887 rc = handle_stfle(vcpu, vsie_page);
890 /* stop not requested by g2 - must have been a kick */
891 if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT))
892 clear_vsie_icpt(vsie_page);
895 if ((scb_s->ipa & 0xf000) != 0xf000)
896 scb_s->ipa += 0x1000;
902 static void release_gmap_shadow(struct vsie_page *vsie_page)
905 gmap_put(vsie_page->gmap);
906 WRITE_ONCE(vsie_page->gmap, NULL);
907 prefix_unmapped(vsie_page);
910 static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
911 struct vsie_page *vsie_page)
918 asce = vcpu->arch.sie_block->gcr[1];
919 cr0.val = vcpu->arch.sie_block->gcr[0];
920 edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
921 edat += edat && test_kvm_facility(vcpu->kvm, 78);
924 * ASCE or EDAT could have changed since last icpt, or the gmap
925 * we're holding has been unshadowed. If the gmap is still valid,
926 * we can safely reuse it.
928 if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat))
931 /* release the old shadow - if any, and mark the prefix as unmapped */
932 release_gmap_shadow(vsie_page);
933 gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
935 return PTR_ERR(gmap);
936 gmap->private = vcpu->kvm;
937 WRITE_ONCE(vsie_page->gmap, gmap);
942 * Register the shadow scb at the VCPU, e.g. for kicking out of vsie.
944 static void register_shadow_scb(struct kvm_vcpu *vcpu,
945 struct vsie_page *vsie_page)
947 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
949 WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s);
951 * External calls have to lead to a kick of the vcpu and
952 * therefore the vsie -> Simulate Wait state.
954 kvm_s390_set_cpuflags(vcpu, CPUSTAT_WAIT);
956 * We have to adjust the g3 epoch by the g2 epoch. The epoch will
957 * automatically be adjusted on tod clock changes via kvm_sync_clock.
960 scb_s->epoch += vcpu->kvm->arch.epoch;
962 if (scb_s->ecd & ECD_MEF) {
963 scb_s->epdx += vcpu->kvm->arch.epdx;
964 if (scb_s->epoch < vcpu->kvm->arch.epoch)
972 * Unregister a shadow scb from a VCPU.
974 static void unregister_shadow_scb(struct kvm_vcpu *vcpu)
976 kvm_s390_clear_cpuflags(vcpu, CPUSTAT_WAIT);
977 WRITE_ONCE(vcpu->arch.vsie_block, NULL);
981 * Run the vsie on a shadowed scb, managing the gmap shadow, handling
982 * prefix pages and faults.
984 * Returns: - 0 if no errors occurred
985 * - > 0 if control has to be given to guest 2
986 * - -ENOMEM if out of memory
988 static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
990 struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
994 rc = acquire_gmap_shadow(vcpu, vsie_page);
996 rc = map_prefix(vcpu, vsie_page);
998 gmap_enable(vsie_page->gmap);
999 update_intervention_requests(vsie_page);
1000 rc = do_vsie_run(vcpu, vsie_page);
1001 gmap_enable(vcpu->arch.gmap);
1003 atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20);
1007 if (rc || scb_s->icptcode || signal_pending(current) ||
1008 kvm_s390_vcpu_has_irq(vcpu, 0))
1012 if (rc == -EFAULT) {
1014 * Addressing exceptions are always presentes as intercepts.
1015 * As addressing exceptions are suppressing and our guest 3 PSW
1016 * points at the responsible instruction, we have to
1017 * forward the PSW and set the ilc. If we can't read guest 3
1018 * instruction, we can use an arbitrary ilc. Let's always use
1019 * ilen = 4 for now, so we can avoid reading in guest 3 virtual
1020 * memory. (we could also fake the shadow so the hardware
1023 scb_s->icptcode = ICPT_PROGI;
1024 scb_s->iprcc = PGM_ADDRESSING;
1026 scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4);
1033 * Get or create a vsie page for a scb address.
1035 * Returns: - address of a vsie page (cached or new one)
1036 * - NULL if the same scb address is already used by another VCPU
1037 * - ERR_PTR(-ENOMEM) if out of memory
1039 static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
1041 struct vsie_page *vsie_page;
1046 page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9);
1049 if (page_ref_inc_return(page) == 2)
1050 return page_to_virt(page);
1055 * We want at least #online_vcpus shadows, so every VCPU can execute
1056 * the VSIE in parallel.
1058 nr_vcpus = atomic_read(&kvm->online_vcpus);
1060 mutex_lock(&kvm->arch.vsie.mutex);
1061 if (kvm->arch.vsie.page_count < nr_vcpus) {
1062 page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA);
1064 mutex_unlock(&kvm->arch.vsie.mutex);
1065 return ERR_PTR(-ENOMEM);
1068 kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = page;
1069 kvm->arch.vsie.page_count++;
1071 /* reuse an existing entry that belongs to nobody */
1073 page = kvm->arch.vsie.pages[kvm->arch.vsie.next];
1074 if (page_ref_inc_return(page) == 2)
1077 kvm->arch.vsie.next++;
1078 kvm->arch.vsie.next %= nr_vcpus;
1080 radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
1083 /* double use of the same address */
1084 if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, page)) {
1086 mutex_unlock(&kvm->arch.vsie.mutex);
1089 mutex_unlock(&kvm->arch.vsie.mutex);
1091 vsie_page = page_to_virt(page);
1092 memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block));
1093 release_gmap_shadow(vsie_page);
1094 vsie_page->fault_addr = 0;
1095 vsie_page->scb_s.ihcpu = 0xffffU;
1099 /* put a vsie page acquired via get_vsie_page */
1100 static void put_vsie_page(struct kvm *kvm, struct vsie_page *vsie_page)
1102 struct page *page = pfn_to_page(__pa(vsie_page) >> PAGE_SHIFT);
1107 int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu)
1109 struct vsie_page *vsie_page;
1110 unsigned long scb_addr;
1113 vcpu->stat.instruction_sie++;
1114 if (!test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIEF2))
1116 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
1117 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
1119 BUILD_BUG_ON(sizeof(struct vsie_page) != PAGE_SIZE);
1120 scb_addr = kvm_s390_get_base_disp_s(vcpu, NULL);
1122 /* 512 byte alignment */
1123 if (unlikely(scb_addr & 0x1ffUL))
1124 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
1126 if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0))
1129 vsie_page = get_vsie_page(vcpu->kvm, scb_addr);
1130 if (IS_ERR(vsie_page))
1131 return PTR_ERR(vsie_page);
1132 else if (!vsie_page)
1133 /* double use of sie control block - simply do nothing */
1136 rc = pin_scb(vcpu, vsie_page, scb_addr);
1139 rc = shadow_scb(vcpu, vsie_page);
1142 rc = pin_blocks(vcpu, vsie_page);
1145 register_shadow_scb(vcpu, vsie_page);
1146 rc = vsie_run(vcpu, vsie_page);
1147 unregister_shadow_scb(vcpu);
1148 unpin_blocks(vcpu, vsie_page);
1150 unshadow_scb(vcpu, vsie_page);
1152 unpin_scb(vcpu, vsie_page, scb_addr);
1154 put_vsie_page(vcpu->kvm, vsie_page);
1156 return rc < 0 ? rc : 0;
1159 /* Init the vsie data structures. To be called when a vm is initialized. */
1160 void kvm_s390_vsie_init(struct kvm *kvm)
1162 mutex_init(&kvm->arch.vsie.mutex);
1163 INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL);
1166 /* Destroy the vsie data structures. To be called when a vm is destroyed. */
1167 void kvm_s390_vsie_destroy(struct kvm *kvm)
1169 struct vsie_page *vsie_page;
1173 mutex_lock(&kvm->arch.vsie.mutex);
1174 for (i = 0; i < kvm->arch.vsie.page_count; i++) {
1175 page = kvm->arch.vsie.pages[i];
1176 kvm->arch.vsie.pages[i] = NULL;
1177 vsie_page = page_to_virt(page);
1178 release_gmap_shadow(vsie_page);
1179 /* free the radix tree entry */
1180 radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
1183 kvm->arch.vsie.page_count = 0;
1184 mutex_unlock(&kvm->arch.vsie.mutex);
1187 void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu)
1189 struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block);
1192 * Even if the VCPU lets go of the shadow sie block reference, it is
1193 * still valid in the cache. So we can safely kick it.
1196 atomic_or(PROG_BLOCK_SIE, &scb->prog20);
1197 if (scb->prog0c & PROG_IN_SIE)
1198 atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags);