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a3508fbe DH |
1 | /* |
2 | * kvm nested virtualization support for s390x | |
3 | * | |
4 | * Copyright IBM Corp. 2016 | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License (version 2 only) | |
8 | * as published by the Free Software Foundation. | |
9 | * | |
10 | * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com> | |
11 | */ | |
12 | #include <linux/vmalloc.h> | |
13 | #include <linux/kvm_host.h> | |
14 | #include <linux/bug.h> | |
15 | #include <linux/list.h> | |
16 | #include <linux/bitmap.h> | |
174cd4b1 IM |
17 | #include <linux/sched/signal.h> |
18 | ||
a3508fbe DH |
19 | #include <asm/gmap.h> |
20 | #include <asm/mmu_context.h> | |
21 | #include <asm/sclp.h> | |
22 | #include <asm/nmi.h> | |
66b630d5 | 23 | #include <asm/dis.h> |
a3508fbe DH |
24 | #include "kvm-s390.h" |
25 | #include "gaccess.h" | |
26 | ||
27 | struct vsie_page { | |
28 | struct kvm_s390_sie_block scb_s; /* 0x0000 */ | |
29 | /* the pinned originial scb */ | |
30 | struct kvm_s390_sie_block *scb_o; /* 0x0200 */ | |
31 | /* the shadow gmap in use by the vsie_page */ | |
32 | struct gmap *gmap; /* 0x0208 */ | |
1b7029be DH |
33 | /* address of the last reported fault to guest2 */ |
34 | unsigned long fault_addr; /* 0x0210 */ | |
35 | __u8 reserved[0x0700 - 0x0218]; /* 0x0218 */ | |
bbeaa58b | 36 | struct kvm_s390_crypto_cb crycb; /* 0x0700 */ |
66b630d5 | 37 | __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */ |
a3508fbe DH |
38 | } __packed; |
39 | ||
40 | /* trigger a validity icpt for the given scb */ | |
41 | static int set_validity_icpt(struct kvm_s390_sie_block *scb, | |
42 | __u16 reason_code) | |
43 | { | |
44 | scb->ipa = 0x1000; | |
45 | scb->ipb = ((__u32) reason_code) << 16; | |
46 | scb->icptcode = ICPT_VALIDITY; | |
47 | return 1; | |
48 | } | |
49 | ||
50 | /* mark the prefix as unmapped, this will block the VSIE */ | |
51 | static void prefix_unmapped(struct vsie_page *vsie_page) | |
52 | { | |
53 | atomic_or(PROG_REQUEST, &vsie_page->scb_s.prog20); | |
54 | } | |
55 | ||
56 | /* mark the prefix as unmapped and wait until the VSIE has been left */ | |
57 | static void prefix_unmapped_sync(struct vsie_page *vsie_page) | |
58 | { | |
59 | prefix_unmapped(vsie_page); | |
60 | if (vsie_page->scb_s.prog0c & PROG_IN_SIE) | |
61 | atomic_or(CPUSTAT_STOP_INT, &vsie_page->scb_s.cpuflags); | |
62 | while (vsie_page->scb_s.prog0c & PROG_IN_SIE) | |
63 | cpu_relax(); | |
64 | } | |
65 | ||
66 | /* mark the prefix as mapped, this will allow the VSIE to run */ | |
67 | static void prefix_mapped(struct vsie_page *vsie_page) | |
68 | { | |
69 | atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20); | |
70 | } | |
71 | ||
06d68a6c DH |
72 | /* test if the prefix is mapped into the gmap shadow */ |
73 | static int prefix_is_mapped(struct vsie_page *vsie_page) | |
74 | { | |
75 | return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST); | |
76 | } | |
a3508fbe DH |
77 | |
78 | /* copy the updated intervention request bits into the shadow scb */ | |
79 | static void update_intervention_requests(struct vsie_page *vsie_page) | |
80 | { | |
81 | const int bits = CPUSTAT_STOP_INT | CPUSTAT_IO_INT | CPUSTAT_EXT_INT; | |
82 | int cpuflags; | |
83 | ||
84 | cpuflags = atomic_read(&vsie_page->scb_o->cpuflags); | |
85 | atomic_andnot(bits, &vsie_page->scb_s.cpuflags); | |
86 | atomic_or(cpuflags & bits, &vsie_page->scb_s.cpuflags); | |
87 | } | |
88 | ||
89 | /* shadow (filter and validate) the cpuflags */ | |
90 | static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
91 | { | |
92 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
93 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
94 | int newflags, cpuflags = atomic_read(&scb_o->cpuflags); | |
95 | ||
96 | /* we don't allow ESA/390 guests */ | |
97 | if (!(cpuflags & CPUSTAT_ZARCH)) | |
98 | return set_validity_icpt(scb_s, 0x0001U); | |
99 | ||
100 | if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS)) | |
101 | return set_validity_icpt(scb_s, 0x0001U); | |
102 | else if (cpuflags & (CPUSTAT_SLSV | CPUSTAT_SLSR)) | |
103 | return set_validity_icpt(scb_s, 0x0007U); | |
104 | ||
105 | /* intervention requests will be set later */ | |
106 | newflags = CPUSTAT_ZARCH; | |
535ef81c DH |
107 | if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8)) |
108 | newflags |= CPUSTAT_GED; | |
109 | if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) { | |
110 | if (cpuflags & CPUSTAT_GED) | |
111 | return set_validity_icpt(scb_s, 0x0001U); | |
112 | newflags |= CPUSTAT_GED2; | |
113 | } | |
77d18f6d DH |
114 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE)) |
115 | newflags |= cpuflags & CPUSTAT_P; | |
a1b7b9b2 DH |
116 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS)) |
117 | newflags |= cpuflags & CPUSTAT_SM; | |
7fd7f39d DH |
118 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS)) |
119 | newflags |= cpuflags & CPUSTAT_IBS; | |
a3508fbe DH |
120 | |
121 | atomic_set(&scb_s->cpuflags, newflags); | |
122 | return 0; | |
123 | } | |
124 | ||
bbeaa58b DH |
125 | /* |
126 | * Create a shadow copy of the crycb block and setup key wrapping, if | |
127 | * requested for guest 3 and enabled for guest 2. | |
128 | * | |
129 | * We only accept format-1 (no AP in g2), but convert it into format-2 | |
130 | * There is nothing to do for format-0. | |
131 | * | |
132 | * Returns: - 0 if shadowed or nothing to do | |
133 | * - > 0 if control has to be given to guest 2 | |
134 | */ | |
135 | static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
136 | { | |
137 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
138 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
139 | u32 crycb_addr = scb_o->crycbd & 0x7ffffff8U; | |
140 | unsigned long *b1, *b2; | |
141 | u8 ecb3_flags; | |
142 | ||
143 | scb_s->crycbd = 0; | |
144 | if (!(scb_o->crycbd & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1)) | |
145 | return 0; | |
146 | /* format-1 is supported with message-security-assist extension 3 */ | |
147 | if (!test_kvm_facility(vcpu->kvm, 76)) | |
148 | return 0; | |
149 | /* we may only allow it if enabled for guest 2 */ | |
150 | ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 & | |
151 | (ECB3_AES | ECB3_DEA); | |
152 | if (!ecb3_flags) | |
153 | return 0; | |
154 | ||
155 | if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK)) | |
156 | return set_validity_icpt(scb_s, 0x003CU); | |
157 | else if (!crycb_addr) | |
158 | return set_validity_icpt(scb_s, 0x0039U); | |
159 | ||
160 | /* copy only the wrapping keys */ | |
161 | if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56)) | |
162 | return set_validity_icpt(scb_s, 0x0035U); | |
163 | ||
164 | scb_s->ecb3 |= ecb3_flags; | |
165 | scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 | | |
166 | CRYCB_FORMAT2; | |
167 | ||
168 | /* xor both blocks in one run */ | |
169 | b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask; | |
170 | b2 = (unsigned long *) | |
171 | vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask; | |
172 | /* as 56%8 == 0, bitmap_xor won't overwrite any data */ | |
173 | bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56); | |
174 | return 0; | |
175 | } | |
176 | ||
3573602b DH |
177 | /* shadow (round up/down) the ibc to avoid validity icpt */ |
178 | static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
179 | { | |
180 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
181 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
182 | __u64 min_ibc = (sclp.ibc >> 16) & 0x0fffU; | |
183 | ||
184 | scb_s->ibc = 0; | |
185 | /* ibc installed in g2 and requested for g3 */ | |
186 | if (vcpu->kvm->arch.model.ibc && (scb_o->ibc & 0x0fffU)) { | |
187 | scb_s->ibc = scb_o->ibc & 0x0fffU; | |
188 | /* takte care of the minimum ibc level of the machine */ | |
189 | if (scb_s->ibc < min_ibc) | |
190 | scb_s->ibc = min_ibc; | |
191 | /* take care of the maximum ibc level set for the guest */ | |
192 | if (scb_s->ibc > vcpu->kvm->arch.model.ibc) | |
193 | scb_s->ibc = vcpu->kvm->arch.model.ibc; | |
194 | } | |
195 | } | |
196 | ||
a3508fbe DH |
197 | /* unshadow the scb, copying parameters back to the real scb */ |
198 | static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
199 | { | |
200 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
201 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
202 | ||
203 | /* interception */ | |
204 | scb_o->icptcode = scb_s->icptcode; | |
205 | scb_o->icptstatus = scb_s->icptstatus; | |
206 | scb_o->ipa = scb_s->ipa; | |
207 | scb_o->ipb = scb_s->ipb; | |
208 | scb_o->gbea = scb_s->gbea; | |
209 | ||
210 | /* timer */ | |
211 | scb_o->cputm = scb_s->cputm; | |
212 | scb_o->ckc = scb_s->ckc; | |
213 | scb_o->todpr = scb_s->todpr; | |
214 | ||
215 | /* guest state */ | |
216 | scb_o->gpsw = scb_s->gpsw; | |
217 | scb_o->gg14 = scb_s->gg14; | |
218 | scb_o->gg15 = scb_s->gg15; | |
219 | memcpy(scb_o->gcr, scb_s->gcr, 128); | |
220 | scb_o->pp = scb_s->pp; | |
221 | ||
222 | /* interrupt intercept */ | |
223 | switch (scb_s->icptcode) { | |
224 | case ICPT_PROGI: | |
225 | case ICPT_INSTPROGI: | |
226 | case ICPT_EXTINT: | |
227 | memcpy((void *)((u64)scb_o + 0xc0), | |
228 | (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0); | |
229 | break; | |
230 | case ICPT_PARTEXEC: | |
231 | /* MVPG only */ | |
232 | memcpy((void *)((u64)scb_o + 0xc0), | |
233 | (void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0); | |
234 | break; | |
235 | } | |
236 | ||
237 | if (scb_s->ihcpu != 0xffffU) | |
238 | scb_o->ihcpu = scb_s->ihcpu; | |
239 | } | |
240 | ||
241 | /* | |
242 | * Setup the shadow scb by copying and checking the relevant parts of the g2 | |
243 | * provided scb. | |
244 | * | |
245 | * Returns: - 0 if the scb has been shadowed | |
246 | * - > 0 if control has to be given to guest 2 | |
247 | */ | |
248 | static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
249 | { | |
250 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
251 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
166ecb3d | 252 | bool had_tx = scb_s->ecb & 0x10U; |
a1b7b9b2 | 253 | unsigned long new_mso = 0; |
a3508fbe DH |
254 | int rc; |
255 | ||
256 | /* make sure we don't have any leftovers when reusing the scb */ | |
257 | scb_s->icptcode = 0; | |
258 | scb_s->eca = 0; | |
259 | scb_s->ecb = 0; | |
260 | scb_s->ecb2 = 0; | |
261 | scb_s->ecb3 = 0; | |
262 | scb_s->ecd = 0; | |
66b630d5 | 263 | scb_s->fac = 0; |
a3508fbe DH |
264 | |
265 | rc = prepare_cpuflags(vcpu, vsie_page); | |
266 | if (rc) | |
267 | goto out; | |
268 | ||
269 | /* timer */ | |
270 | scb_s->cputm = scb_o->cputm; | |
271 | scb_s->ckc = scb_o->ckc; | |
272 | scb_s->todpr = scb_o->todpr; | |
273 | scb_s->epoch = scb_o->epoch; | |
274 | ||
275 | /* guest state */ | |
276 | scb_s->gpsw = scb_o->gpsw; | |
277 | scb_s->gg14 = scb_o->gg14; | |
278 | scb_s->gg15 = scb_o->gg15; | |
279 | memcpy(scb_s->gcr, scb_o->gcr, 128); | |
280 | scb_s->pp = scb_o->pp; | |
281 | ||
282 | /* interception / execution handling */ | |
283 | scb_s->gbea = scb_o->gbea; | |
284 | scb_s->lctl = scb_o->lctl; | |
285 | scb_s->svcc = scb_o->svcc; | |
286 | scb_s->ictl = scb_o->ictl; | |
287 | /* | |
288 | * SKEY handling functions can't deal with false setting of PTE invalid | |
289 | * bits. Therefore we cannot provide interpretation and would later | |
290 | * have to provide own emulation handlers. | |
291 | */ | |
292 | scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE; | |
293 | scb_s->icpua = scb_o->icpua; | |
294 | ||
a1b7b9b2 DH |
295 | if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM)) |
296 | new_mso = scb_o->mso & 0xfffffffffff00000UL; | |
06d68a6c DH |
297 | /* if the hva of the prefix changes, we have to remap the prefix */ |
298 | if (scb_s->mso != new_mso || scb_s->prefix != scb_o->prefix) | |
299 | prefix_unmapped(vsie_page); | |
a3508fbe DH |
300 | /* SIE will do mso/msl validity and exception checks for us */ |
301 | scb_s->msl = scb_o->msl & 0xfffffffffff00000UL; | |
06d68a6c | 302 | scb_s->mso = new_mso; |
a3508fbe DH |
303 | scb_s->prefix = scb_o->prefix; |
304 | ||
305 | /* We have to definetly flush the tlb if this scb never ran */ | |
306 | if (scb_s->ihcpu != 0xffffU) | |
307 | scb_s->ihcpu = scb_o->ihcpu; | |
308 | ||
309 | /* MVPG and Protection Exception Interpretation are always available */ | |
310 | scb_s->eca |= scb_o->eca & 0x01002000U; | |
4ceafa90 DH |
311 | /* Host-protection-interruption introduced with ESOP */ |
312 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP)) | |
313 | scb_s->ecb |= scb_o->ecb & 0x02U; | |
166ecb3d DH |
314 | /* transactional execution */ |
315 | if (test_kvm_facility(vcpu->kvm, 73)) { | |
316 | /* remap the prefix is tx is toggled on */ | |
317 | if ((scb_o->ecb & 0x10U) && !had_tx) | |
318 | prefix_unmapped(vsie_page); | |
319 | scb_s->ecb |= scb_o->ecb & 0x10U; | |
320 | } | |
c9bc1eab DH |
321 | /* SIMD */ |
322 | if (test_kvm_facility(vcpu->kvm, 129)) { | |
323 | scb_s->eca |= scb_o->eca & 0x00020000U; | |
324 | scb_s->ecd |= scb_o->ecd & 0x20000000U; | |
325 | } | |
588438cb DH |
326 | /* Run-time-Instrumentation */ |
327 | if (test_kvm_facility(vcpu->kvm, 64)) | |
328 | scb_s->ecb3 |= scb_o->ecb3 & 0x01U; | |
cd1836f5 JF |
329 | /* Instruction Execution Prevention */ |
330 | if (test_kvm_facility(vcpu->kvm, 130)) | |
331 | scb_s->ecb2 |= scb_o->ecb2 & 0x20U; | |
0615a326 DH |
332 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF)) |
333 | scb_s->eca |= scb_o->eca & 0x00000001U; | |
5630a8e8 DH |
334 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB)) |
335 | scb_s->eca |= scb_o->eca & 0x40000000U; | |
13ee3f67 DH |
336 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI)) |
337 | scb_s->eca |= scb_o->eca & 0x80000000U; | |
a3508fbe | 338 | |
3573602b | 339 | prepare_ibc(vcpu, vsie_page); |
bbeaa58b | 340 | rc = shadow_crycb(vcpu, vsie_page); |
a3508fbe DH |
341 | out: |
342 | if (rc) | |
343 | unshadow_scb(vcpu, vsie_page); | |
344 | return rc; | |
345 | } | |
346 | ||
347 | void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start, | |
348 | unsigned long end) | |
349 | { | |
350 | struct kvm *kvm = gmap->private; | |
351 | struct vsie_page *cur; | |
352 | unsigned long prefix; | |
353 | struct page *page; | |
354 | int i; | |
355 | ||
356 | if (!gmap_is_shadow(gmap)) | |
357 | return; | |
358 | if (start >= 1UL << 31) | |
359 | /* We are only interested in prefix pages */ | |
360 | return; | |
361 | ||
362 | /* | |
363 | * Only new shadow blocks are added to the list during runtime, | |
364 | * therefore we can safely reference them all the time. | |
365 | */ | |
366 | for (i = 0; i < kvm->arch.vsie.page_count; i++) { | |
367 | page = READ_ONCE(kvm->arch.vsie.pages[i]); | |
368 | if (!page) | |
369 | continue; | |
370 | cur = page_to_virt(page); | |
371 | if (READ_ONCE(cur->gmap) != gmap) | |
372 | continue; | |
373 | prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT; | |
374 | /* with mso/msl, the prefix lies at an offset */ | |
375 | prefix += cur->scb_s.mso; | |
166ecb3d | 376 | if (prefix <= end && start <= prefix + 2 * PAGE_SIZE - 1) |
a3508fbe DH |
377 | prefix_unmapped_sync(cur); |
378 | } | |
379 | } | |
380 | ||
381 | /* | |
166ecb3d | 382 | * Map the first prefix page and if tx is enabled also the second prefix page. |
a3508fbe DH |
383 | * |
384 | * The prefix will be protected, a gmap notifier will inform about unmaps. | |
385 | * The shadow scb must not be executed until the prefix is remapped, this is | |
386 | * guaranteed by properly handling PROG_REQUEST. | |
387 | * | |
388 | * Returns: - 0 on if successfully mapped or already mapped | |
389 | * - > 0 if control has to be given to guest 2 | |
390 | * - -EAGAIN if the caller can retry immediately | |
391 | * - -ENOMEM if out of memory | |
392 | */ | |
393 | static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
394 | { | |
395 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
396 | u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT; | |
397 | int rc; | |
398 | ||
06d68a6c DH |
399 | if (prefix_is_mapped(vsie_page)) |
400 | return 0; | |
401 | ||
a3508fbe DH |
402 | /* mark it as mapped so we can catch any concurrent unmappers */ |
403 | prefix_mapped(vsie_page); | |
404 | ||
405 | /* with mso/msl, the prefix lies at offset *mso* */ | |
406 | prefix += scb_s->mso; | |
407 | ||
408 | rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix); | |
166ecb3d DH |
409 | if (!rc && (scb_s->ecb & 0x10U)) |
410 | rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, | |
411 | prefix + PAGE_SIZE); | |
a3508fbe DH |
412 | /* |
413 | * We don't have to mprotect, we will be called for all unshadows. | |
414 | * SIE will detect if protection applies and trigger a validity. | |
415 | */ | |
416 | if (rc) | |
417 | prefix_unmapped(vsie_page); | |
418 | if (rc > 0 || rc == -EFAULT) | |
419 | rc = set_validity_icpt(scb_s, 0x0037U); | |
420 | return rc; | |
421 | } | |
422 | ||
423 | /* | |
424 | * Pin the guest page given by gpa and set hpa to the pinned host address. | |
425 | * Will always be pinned writable. | |
426 | * | |
427 | * Returns: - 0 on success | |
428 | * - -EINVAL if the gpa is not valid guest storage | |
429 | * - -ENOMEM if out of memory | |
430 | */ | |
431 | static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa) | |
432 | { | |
433 | struct page *page; | |
434 | hva_t hva; | |
435 | int rc; | |
436 | ||
437 | hva = gfn_to_hva(kvm, gpa_to_gfn(gpa)); | |
438 | if (kvm_is_error_hva(hva)) | |
439 | return -EINVAL; | |
440 | rc = get_user_pages_fast(hva, 1, 1, &page); | |
441 | if (rc < 0) | |
442 | return rc; | |
443 | else if (rc != 1) | |
444 | return -ENOMEM; | |
445 | *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK); | |
446 | return 0; | |
447 | } | |
448 | ||
449 | /* Unpins a page previously pinned via pin_guest_page, marking it as dirty. */ | |
450 | static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa) | |
451 | { | |
452 | struct page *page; | |
453 | ||
454 | page = virt_to_page(hpa); | |
455 | set_page_dirty_lock(page); | |
456 | put_page(page); | |
457 | /* mark the page always as dirty for migration */ | |
458 | mark_page_dirty(kvm, gpa_to_gfn(gpa)); | |
459 | } | |
460 | ||
461 | /* unpin all blocks previously pinned by pin_blocks(), marking them dirty */ | |
462 | static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
463 | { | |
464 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
465 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
466 | hpa_t hpa; | |
467 | gpa_t gpa; | |
468 | ||
469 | hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol; | |
470 | if (hpa) { | |
471 | gpa = scb_o->scaol & ~0xfUL; | |
19c439b5 DH |
472 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO)) |
473 | gpa |= (u64) scb_o->scaoh << 32; | |
a3508fbe DH |
474 | unpin_guest_page(vcpu->kvm, gpa, hpa); |
475 | scb_s->scaol = 0; | |
476 | scb_s->scaoh = 0; | |
477 | } | |
166ecb3d DH |
478 | |
479 | hpa = scb_s->itdba; | |
480 | if (hpa) { | |
481 | gpa = scb_o->itdba & ~0xffUL; | |
482 | unpin_guest_page(vcpu->kvm, gpa, hpa); | |
483 | scb_s->itdba = 0; | |
484 | } | |
c9bc1eab DH |
485 | |
486 | hpa = scb_s->gvrd; | |
487 | if (hpa) { | |
488 | gpa = scb_o->gvrd & ~0x1ffUL; | |
489 | unpin_guest_page(vcpu->kvm, gpa, hpa); | |
490 | scb_s->gvrd = 0; | |
491 | } | |
588438cb DH |
492 | |
493 | hpa = scb_s->riccbd; | |
494 | if (hpa) { | |
495 | gpa = scb_o->riccbd & ~0x3fUL; | |
496 | unpin_guest_page(vcpu->kvm, gpa, hpa); | |
497 | scb_s->riccbd = 0; | |
498 | } | |
a3508fbe DH |
499 | } |
500 | ||
501 | /* | |
502 | * Instead of shadowing some blocks, we can simply forward them because the | |
503 | * addresses in the scb are 64 bit long. | |
504 | * | |
505 | * This works as long as the data lies in one page. If blocks ever exceed one | |
506 | * page, we have to fall back to shadowing. | |
507 | * | |
508 | * As we reuse the sca, the vcpu pointers contained in it are invalid. We must | |
509 | * therefore not enable any facilities that access these pointers (e.g. SIGPIF). | |
510 | * | |
511 | * Returns: - 0 if all blocks were pinned. | |
512 | * - > 0 if control has to be given to guest 2 | |
513 | * - -ENOMEM if out of memory | |
514 | */ | |
515 | static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
516 | { | |
517 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
518 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
519 | hpa_t hpa; | |
520 | gpa_t gpa; | |
521 | int rc = 0; | |
522 | ||
523 | gpa = scb_o->scaol & ~0xfUL; | |
19c439b5 DH |
524 | if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO)) |
525 | gpa |= (u64) scb_o->scaoh << 32; | |
a3508fbe DH |
526 | if (gpa) { |
527 | if (!(gpa & ~0x1fffUL)) | |
528 | rc = set_validity_icpt(scb_s, 0x0038U); | |
529 | else if ((gpa & ~0x1fffUL) == kvm_s390_get_prefix(vcpu)) | |
530 | rc = set_validity_icpt(scb_s, 0x0011U); | |
531 | else if ((gpa & PAGE_MASK) != | |
532 | ((gpa + sizeof(struct bsca_block) - 1) & PAGE_MASK)) | |
533 | rc = set_validity_icpt(scb_s, 0x003bU); | |
534 | if (!rc) { | |
535 | rc = pin_guest_page(vcpu->kvm, gpa, &hpa); | |
536 | if (rc == -EINVAL) | |
537 | rc = set_validity_icpt(scb_s, 0x0034U); | |
538 | } | |
539 | if (rc) | |
540 | goto unpin; | |
541 | scb_s->scaoh = (u32)((u64)hpa >> 32); | |
542 | scb_s->scaol = (u32)(u64)hpa; | |
543 | } | |
166ecb3d DH |
544 | |
545 | gpa = scb_o->itdba & ~0xffUL; | |
546 | if (gpa && (scb_s->ecb & 0x10U)) { | |
547 | if (!(gpa & ~0x1fffU)) { | |
548 | rc = set_validity_icpt(scb_s, 0x0080U); | |
549 | goto unpin; | |
550 | } | |
551 | /* 256 bytes cannot cross page boundaries */ | |
552 | rc = pin_guest_page(vcpu->kvm, gpa, &hpa); | |
553 | if (rc == -EINVAL) | |
554 | rc = set_validity_icpt(scb_s, 0x0080U); | |
555 | if (rc) | |
556 | goto unpin; | |
557 | scb_s->itdba = hpa; | |
558 | } | |
c9bc1eab DH |
559 | |
560 | gpa = scb_o->gvrd & ~0x1ffUL; | |
561 | if (gpa && (scb_s->eca & 0x00020000U) && | |
562 | !(scb_s->ecd & 0x20000000U)) { | |
563 | if (!(gpa & ~0x1fffUL)) { | |
564 | rc = set_validity_icpt(scb_s, 0x1310U); | |
565 | goto unpin; | |
566 | } | |
567 | /* | |
568 | * 512 bytes vector registers cannot cross page boundaries | |
569 | * if this block gets bigger, we have to shadow it. | |
570 | */ | |
571 | rc = pin_guest_page(vcpu->kvm, gpa, &hpa); | |
572 | if (rc == -EINVAL) | |
573 | rc = set_validity_icpt(scb_s, 0x1310U); | |
574 | if (rc) | |
575 | goto unpin; | |
576 | scb_s->gvrd = hpa; | |
577 | } | |
588438cb DH |
578 | |
579 | gpa = scb_o->riccbd & ~0x3fUL; | |
580 | if (gpa && (scb_s->ecb3 & 0x01U)) { | |
581 | if (!(gpa & ~0x1fffUL)) { | |
582 | rc = set_validity_icpt(scb_s, 0x0043U); | |
583 | goto unpin; | |
584 | } | |
585 | /* 64 bytes cannot cross page boundaries */ | |
586 | rc = pin_guest_page(vcpu->kvm, gpa, &hpa); | |
587 | if (rc == -EINVAL) | |
588 | rc = set_validity_icpt(scb_s, 0x0043U); | |
589 | /* Validity 0x0044 will be checked by SIE */ | |
590 | if (rc) | |
591 | goto unpin; | |
4d21cef3 | 592 | scb_s->riccbd = hpa; |
588438cb | 593 | } |
a3508fbe DH |
594 | return 0; |
595 | unpin: | |
596 | unpin_blocks(vcpu, vsie_page); | |
597 | return rc; | |
598 | } | |
599 | ||
600 | /* unpin the scb provided by guest 2, marking it as dirty */ | |
601 | static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, | |
602 | gpa_t gpa) | |
603 | { | |
604 | hpa_t hpa = (hpa_t) vsie_page->scb_o; | |
605 | ||
606 | if (hpa) | |
607 | unpin_guest_page(vcpu->kvm, gpa, hpa); | |
608 | vsie_page->scb_o = NULL; | |
609 | } | |
610 | ||
611 | /* | |
612 | * Pin the scb at gpa provided by guest 2 at vsie_page->scb_o. | |
613 | * | |
614 | * Returns: - 0 if the scb was pinned. | |
615 | * - > 0 if control has to be given to guest 2 | |
616 | * - -ENOMEM if out of memory | |
617 | */ | |
618 | static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, | |
619 | gpa_t gpa) | |
620 | { | |
621 | hpa_t hpa; | |
622 | int rc; | |
623 | ||
624 | rc = pin_guest_page(vcpu->kvm, gpa, &hpa); | |
625 | if (rc == -EINVAL) { | |
626 | rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); | |
627 | if (!rc) | |
628 | rc = 1; | |
629 | } | |
630 | if (!rc) | |
631 | vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; | |
632 | return rc; | |
633 | } | |
634 | ||
635 | /* | |
636 | * Inject a fault into guest 2. | |
637 | * | |
638 | * Returns: - > 0 if control has to be given to guest 2 | |
639 | * < 0 if an error occurred during injection. | |
640 | */ | |
641 | static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr, | |
642 | bool write_flag) | |
643 | { | |
644 | struct kvm_s390_pgm_info pgm = { | |
645 | .code = code, | |
646 | .trans_exc_code = | |
647 | /* 0-51: virtual address */ | |
648 | (vaddr & 0xfffffffffffff000UL) | | |
649 | /* 52-53: store / fetch */ | |
650 | (((unsigned int) !write_flag) + 1) << 10, | |
651 | /* 62-63: asce id (alway primary == 0) */ | |
652 | .exc_access_id = 0, /* always primary */ | |
653 | .op_access_id = 0, /* not MVPG */ | |
654 | }; | |
655 | int rc; | |
656 | ||
657 | if (code == PGM_PROTECTION) | |
658 | pgm.trans_exc_code |= 0x4UL; | |
659 | ||
660 | rc = kvm_s390_inject_prog_irq(vcpu, &pgm); | |
661 | return rc ? rc : 1; | |
662 | } | |
663 | ||
664 | /* | |
665 | * Handle a fault during vsie execution on a gmap shadow. | |
666 | * | |
667 | * Returns: - 0 if the fault was resolved | |
668 | * - > 0 if control has to be given to guest 2 | |
669 | * - < 0 if an error occurred | |
670 | */ | |
671 | static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
672 | { | |
673 | int rc; | |
674 | ||
675 | if (current->thread.gmap_int_code == PGM_PROTECTION) | |
676 | /* we can directly forward all protection exceptions */ | |
677 | return inject_fault(vcpu, PGM_PROTECTION, | |
678 | current->thread.gmap_addr, 1); | |
679 | ||
680 | rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, | |
681 | current->thread.gmap_addr); | |
682 | if (rc > 0) { | |
683 | rc = inject_fault(vcpu, rc, | |
684 | current->thread.gmap_addr, | |
685 | current->thread.gmap_write_flag); | |
1b7029be DH |
686 | if (rc >= 0) |
687 | vsie_page->fault_addr = current->thread.gmap_addr; | |
a3508fbe DH |
688 | } |
689 | return rc; | |
690 | } | |
691 | ||
1b7029be DH |
692 | /* |
693 | * Retry the previous fault that required guest 2 intervention. This avoids | |
694 | * one superfluous SIE re-entry and direct exit. | |
695 | * | |
696 | * Will ignore any errors. The next SIE fault will do proper fault handling. | |
697 | */ | |
698 | static void handle_last_fault(struct kvm_vcpu *vcpu, | |
699 | struct vsie_page *vsie_page) | |
700 | { | |
701 | if (vsie_page->fault_addr) | |
702 | kvm_s390_shadow_fault(vcpu, vsie_page->gmap, | |
703 | vsie_page->fault_addr); | |
704 | vsie_page->fault_addr = 0; | |
705 | } | |
706 | ||
a3508fbe DH |
707 | static inline void clear_vsie_icpt(struct vsie_page *vsie_page) |
708 | { | |
709 | vsie_page->scb_s.icptcode = 0; | |
710 | } | |
711 | ||
66b630d5 DH |
712 | /* rewind the psw and clear the vsie icpt, so we can retry execution */ |
713 | static void retry_vsie_icpt(struct vsie_page *vsie_page) | |
714 | { | |
715 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
716 | int ilen = insn_length(scb_s->ipa >> 8); | |
717 | ||
718 | /* take care of EXECUTE instructions */ | |
719 | if (scb_s->icptstatus & 1) { | |
720 | ilen = (scb_s->icptstatus >> 4) & 0x6; | |
721 | if (!ilen) | |
722 | ilen = 4; | |
723 | } | |
724 | scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, ilen); | |
725 | clear_vsie_icpt(vsie_page); | |
726 | } | |
727 | ||
728 | /* | |
729 | * Try to shadow + enable the guest 2 provided facility list. | |
730 | * Retry instruction execution if enabled for and provided by guest 2. | |
731 | * | |
732 | * Returns: - 0 if handled (retry or guest 2 icpt) | |
733 | * - > 0 if control has to be given to guest 2 | |
734 | */ | |
735 | static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
736 | { | |
737 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
738 | __u32 fac = vsie_page->scb_o->fac & 0x7ffffff8U; | |
739 | ||
740 | if (fac && test_kvm_facility(vcpu->kvm, 7)) { | |
741 | retry_vsie_icpt(vsie_page); | |
742 | if (read_guest_real(vcpu, fac, &vsie_page->fac, | |
743 | sizeof(vsie_page->fac))) | |
744 | return set_validity_icpt(scb_s, 0x1090U); | |
745 | scb_s->fac = (__u32)(__u64) &vsie_page->fac; | |
746 | } | |
747 | return 0; | |
748 | } | |
749 | ||
a3508fbe DH |
750 | /* |
751 | * Run the vsie on a shadow scb and a shadow gmap, without any further | |
752 | * sanity checks, handling SIE faults. | |
753 | * | |
754 | * Returns: - 0 everything went fine | |
755 | * - > 0 if control has to be given to guest 2 | |
756 | * - < 0 if an error occurred | |
757 | */ | |
758 | static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
759 | { | |
760 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
761 | struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; | |
762 | int rc; | |
763 | ||
1b7029be DH |
764 | handle_last_fault(vcpu, vsie_page); |
765 | ||
a3508fbe DH |
766 | if (need_resched()) |
767 | schedule(); | |
768 | if (test_cpu_flag(CIF_MCCK_PENDING)) | |
769 | s390_handle_mcck(); | |
770 | ||
771 | srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); | |
772 | local_irq_disable(); | |
6edaa530 | 773 | guest_enter_irqoff(); |
a3508fbe DH |
774 | local_irq_enable(); |
775 | ||
776 | rc = sie64a(scb_s, vcpu->run->s.regs.gprs); | |
777 | ||
778 | local_irq_disable(); | |
6edaa530 | 779 | guest_exit_irqoff(); |
a3508fbe DH |
780 | local_irq_enable(); |
781 | vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); | |
782 | ||
783 | if (rc > 0) | |
784 | rc = 0; /* we could still have an icpt */ | |
785 | else if (rc == -EFAULT) | |
786 | return handle_fault(vcpu, vsie_page); | |
787 | ||
788 | switch (scb_s->icptcode) { | |
66b630d5 DH |
789 | case ICPT_INST: |
790 | if (scb_s->ipa == 0xb2b0) | |
791 | rc = handle_stfle(vcpu, vsie_page); | |
792 | break; | |
a3508fbe DH |
793 | case ICPT_STOP: |
794 | /* stop not requested by g2 - must have been a kick */ | |
795 | if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT)) | |
796 | clear_vsie_icpt(vsie_page); | |
797 | break; | |
798 | case ICPT_VALIDITY: | |
799 | if ((scb_s->ipa & 0xf000) != 0xf000) | |
800 | scb_s->ipa += 0x1000; | |
801 | break; | |
802 | } | |
803 | return rc; | |
804 | } | |
805 | ||
806 | static void release_gmap_shadow(struct vsie_page *vsie_page) | |
807 | { | |
808 | if (vsie_page->gmap) | |
809 | gmap_put(vsie_page->gmap); | |
810 | WRITE_ONCE(vsie_page->gmap, NULL); | |
06d68a6c | 811 | prefix_unmapped(vsie_page); |
a3508fbe DH |
812 | } |
813 | ||
814 | static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, | |
815 | struct vsie_page *vsie_page) | |
816 | { | |
817 | unsigned long asce; | |
818 | union ctlreg0 cr0; | |
819 | struct gmap *gmap; | |
820 | int edat; | |
821 | ||
822 | asce = vcpu->arch.sie_block->gcr[1]; | |
823 | cr0.val = vcpu->arch.sie_block->gcr[0]; | |
824 | edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8); | |
825 | edat += edat && test_kvm_facility(vcpu->kvm, 78); | |
826 | ||
06d68a6c DH |
827 | /* |
828 | * ASCE or EDAT could have changed since last icpt, or the gmap | |
829 | * we're holding has been unshadowed. If the gmap is still valid, | |
830 | * we can safely reuse it. | |
831 | */ | |
832 | if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) | |
833 | return 0; | |
834 | ||
835 | /* release the old shadow - if any, and mark the prefix as unmapped */ | |
836 | release_gmap_shadow(vsie_page); | |
a3508fbe DH |
837 | gmap = gmap_shadow(vcpu->arch.gmap, asce, edat); |
838 | if (IS_ERR(gmap)) | |
839 | return PTR_ERR(gmap); | |
840 | gmap->private = vcpu->kvm; | |
841 | WRITE_ONCE(vsie_page->gmap, gmap); | |
842 | return 0; | |
843 | } | |
844 | ||
adbf1698 DH |
845 | /* |
846 | * Register the shadow scb at the VCPU, e.g. for kicking out of vsie. | |
847 | */ | |
848 | static void register_shadow_scb(struct kvm_vcpu *vcpu, | |
849 | struct vsie_page *vsie_page) | |
850 | { | |
91473b48 DH |
851 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; |
852 | ||
adbf1698 | 853 | WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s); |
b917ae57 DH |
854 | /* |
855 | * External calls have to lead to a kick of the vcpu and | |
856 | * therefore the vsie -> Simulate Wait state. | |
857 | */ | |
858 | atomic_or(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); | |
91473b48 DH |
859 | /* |
860 | * We have to adjust the g3 epoch by the g2 epoch. The epoch will | |
861 | * automatically be adjusted on tod clock changes via kvm_sync_clock. | |
862 | */ | |
863 | preempt_disable(); | |
864 | scb_s->epoch += vcpu->kvm->arch.epoch; | |
865 | preempt_enable(); | |
adbf1698 DH |
866 | } |
867 | ||
868 | /* | |
869 | * Unregister a shadow scb from a VCPU. | |
870 | */ | |
871 | static void unregister_shadow_scb(struct kvm_vcpu *vcpu) | |
872 | { | |
b917ae57 | 873 | atomic_andnot(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); |
adbf1698 DH |
874 | WRITE_ONCE(vcpu->arch.vsie_block, NULL); |
875 | } | |
876 | ||
a3508fbe DH |
877 | /* |
878 | * Run the vsie on a shadowed scb, managing the gmap shadow, handling | |
879 | * prefix pages and faults. | |
880 | * | |
881 | * Returns: - 0 if no errors occurred | |
882 | * - > 0 if control has to be given to guest 2 | |
883 | * - -ENOMEM if out of memory | |
884 | */ | |
885 | static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) | |
886 | { | |
887 | struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; | |
888 | int rc = 0; | |
889 | ||
890 | while (1) { | |
891 | rc = acquire_gmap_shadow(vcpu, vsie_page); | |
892 | if (!rc) | |
893 | rc = map_prefix(vcpu, vsie_page); | |
894 | if (!rc) { | |
895 | gmap_enable(vsie_page->gmap); | |
896 | update_intervention_requests(vsie_page); | |
897 | rc = do_vsie_run(vcpu, vsie_page); | |
898 | gmap_enable(vcpu->arch.gmap); | |
899 | } | |
adbf1698 | 900 | atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20); |
a3508fbe DH |
901 | |
902 | if (rc == -EAGAIN) | |
903 | rc = 0; | |
904 | if (rc || scb_s->icptcode || signal_pending(current) || | |
905 | kvm_s390_vcpu_has_irq(vcpu, 0)) | |
906 | break; | |
0b925159 | 907 | } |
a3508fbe DH |
908 | |
909 | if (rc == -EFAULT) { | |
910 | /* | |
911 | * Addressing exceptions are always presentes as intercepts. | |
912 | * As addressing exceptions are suppressing and our guest 3 PSW | |
913 | * points at the responsible instruction, we have to | |
914 | * forward the PSW and set the ilc. If we can't read guest 3 | |
915 | * instruction, we can use an arbitrary ilc. Let's always use | |
916 | * ilen = 4 for now, so we can avoid reading in guest 3 virtual | |
917 | * memory. (we could also fake the shadow so the hardware | |
918 | * handles it). | |
919 | */ | |
920 | scb_s->icptcode = ICPT_PROGI; | |
921 | scb_s->iprcc = PGM_ADDRESSING; | |
922 | scb_s->pgmilc = 4; | |
923 | scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4); | |
924 | } | |
925 | return rc; | |
926 | } | |
927 | ||
928 | /* | |
929 | * Get or create a vsie page for a scb address. | |
930 | * | |
931 | * Returns: - address of a vsie page (cached or new one) | |
932 | * - NULL if the same scb address is already used by another VCPU | |
933 | * - ERR_PTR(-ENOMEM) if out of memory | |
934 | */ | |
935 | static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr) | |
936 | { | |
937 | struct vsie_page *vsie_page; | |
938 | struct page *page; | |
939 | int nr_vcpus; | |
940 | ||
941 | rcu_read_lock(); | |
942 | page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9); | |
943 | rcu_read_unlock(); | |
944 | if (page) { | |
945 | if (page_ref_inc_return(page) == 2) | |
946 | return page_to_virt(page); | |
947 | page_ref_dec(page); | |
948 | } | |
949 | ||
950 | /* | |
951 | * We want at least #online_vcpus shadows, so every VCPU can execute | |
952 | * the VSIE in parallel. | |
953 | */ | |
954 | nr_vcpus = atomic_read(&kvm->online_vcpus); | |
955 | ||
956 | mutex_lock(&kvm->arch.vsie.mutex); | |
957 | if (kvm->arch.vsie.page_count < nr_vcpus) { | |
66b630d5 | 958 | page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA); |
a3508fbe DH |
959 | if (!page) { |
960 | mutex_unlock(&kvm->arch.vsie.mutex); | |
961 | return ERR_PTR(-ENOMEM); | |
962 | } | |
963 | page_ref_inc(page); | |
964 | kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = page; | |
965 | kvm->arch.vsie.page_count++; | |
966 | } else { | |
967 | /* reuse an existing entry that belongs to nobody */ | |
968 | while (true) { | |
969 | page = kvm->arch.vsie.pages[kvm->arch.vsie.next]; | |
970 | if (page_ref_inc_return(page) == 2) | |
971 | break; | |
972 | page_ref_dec(page); | |
973 | kvm->arch.vsie.next++; | |
974 | kvm->arch.vsie.next %= nr_vcpus; | |
975 | } | |
976 | radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9); | |
977 | } | |
978 | page->index = addr; | |
979 | /* double use of the same address */ | |
980 | if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, page)) { | |
981 | page_ref_dec(page); | |
982 | mutex_unlock(&kvm->arch.vsie.mutex); | |
983 | return NULL; | |
984 | } | |
985 | mutex_unlock(&kvm->arch.vsie.mutex); | |
986 | ||
987 | vsie_page = page_to_virt(page); | |
988 | memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block)); | |
06d68a6c | 989 | release_gmap_shadow(vsie_page); |
1b7029be | 990 | vsie_page->fault_addr = 0; |
a3508fbe DH |
991 | vsie_page->scb_s.ihcpu = 0xffffU; |
992 | return vsie_page; | |
993 | } | |
994 | ||
995 | /* put a vsie page acquired via get_vsie_page */ | |
996 | static void put_vsie_page(struct kvm *kvm, struct vsie_page *vsie_page) | |
997 | { | |
998 | struct page *page = pfn_to_page(__pa(vsie_page) >> PAGE_SHIFT); | |
999 | ||
1000 | page_ref_dec(page); | |
1001 | } | |
1002 | ||
1003 | int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu) | |
1004 | { | |
1005 | struct vsie_page *vsie_page; | |
1006 | unsigned long scb_addr; | |
1007 | int rc; | |
1008 | ||
1009 | vcpu->stat.instruction_sie++; | |
1010 | if (!test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIEF2)) | |
1011 | return -EOPNOTSUPP; | |
1012 | if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) | |
1013 | return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); | |
1014 | ||
1015 | BUILD_BUG_ON(sizeof(struct vsie_page) != 4096); | |
1016 | scb_addr = kvm_s390_get_base_disp_s(vcpu, NULL); | |
1017 | ||
1018 | /* 512 byte alignment */ | |
1019 | if (unlikely(scb_addr & 0x1ffUL)) | |
1020 | return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); | |
1021 | ||
1022 | if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0)) | |
1023 | return 0; | |
1024 | ||
1025 | vsie_page = get_vsie_page(vcpu->kvm, scb_addr); | |
1026 | if (IS_ERR(vsie_page)) | |
1027 | return PTR_ERR(vsie_page); | |
1028 | else if (!vsie_page) | |
1029 | /* double use of sie control block - simply do nothing */ | |
1030 | return 0; | |
1031 | ||
1032 | rc = pin_scb(vcpu, vsie_page, scb_addr); | |
1033 | if (rc) | |
1034 | goto out_put; | |
1035 | rc = shadow_scb(vcpu, vsie_page); | |
1036 | if (rc) | |
1037 | goto out_unpin_scb; | |
1038 | rc = pin_blocks(vcpu, vsie_page); | |
1039 | if (rc) | |
1040 | goto out_unshadow; | |
adbf1698 | 1041 | register_shadow_scb(vcpu, vsie_page); |
a3508fbe | 1042 | rc = vsie_run(vcpu, vsie_page); |
adbf1698 | 1043 | unregister_shadow_scb(vcpu); |
a3508fbe DH |
1044 | unpin_blocks(vcpu, vsie_page); |
1045 | out_unshadow: | |
1046 | unshadow_scb(vcpu, vsie_page); | |
1047 | out_unpin_scb: | |
1048 | unpin_scb(vcpu, vsie_page, scb_addr); | |
1049 | out_put: | |
1050 | put_vsie_page(vcpu->kvm, vsie_page); | |
1051 | ||
1052 | return rc < 0 ? rc : 0; | |
1053 | } | |
1054 | ||
1055 | /* Init the vsie data structures. To be called when a vm is initialized. */ | |
1056 | void kvm_s390_vsie_init(struct kvm *kvm) | |
1057 | { | |
1058 | mutex_init(&kvm->arch.vsie.mutex); | |
1059 | INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL); | |
1060 | } | |
1061 | ||
1062 | /* Destroy the vsie data structures. To be called when a vm is destroyed. */ | |
1063 | void kvm_s390_vsie_destroy(struct kvm *kvm) | |
1064 | { | |
06d68a6c | 1065 | struct vsie_page *vsie_page; |
a3508fbe DH |
1066 | struct page *page; |
1067 | int i; | |
1068 | ||
1069 | mutex_lock(&kvm->arch.vsie.mutex); | |
1070 | for (i = 0; i < kvm->arch.vsie.page_count; i++) { | |
1071 | page = kvm->arch.vsie.pages[i]; | |
1072 | kvm->arch.vsie.pages[i] = NULL; | |
06d68a6c DH |
1073 | vsie_page = page_to_virt(page); |
1074 | release_gmap_shadow(vsie_page); | |
a3508fbe DH |
1075 | /* free the radix tree entry */ |
1076 | radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9); | |
1077 | __free_page(page); | |
1078 | } | |
1079 | kvm->arch.vsie.page_count = 0; | |
1080 | mutex_unlock(&kvm->arch.vsie.mutex); | |
1081 | } | |
adbf1698 DH |
1082 | |
1083 | void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu) | |
1084 | { | |
1085 | struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block); | |
1086 | ||
1087 | /* | |
1088 | * Even if the VCPU lets go of the shadow sie block reference, it is | |
1089 | * still valid in the cache. So we can safely kick it. | |
1090 | */ | |
1091 | if (scb) { | |
1092 | atomic_or(PROG_BLOCK_SIE, &scb->prog20); | |
1093 | if (scb->prog0c & PROG_IN_SIE) | |
1094 | atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags); | |
1095 | } | |
1096 | } |