1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2009 SUSE Linux Products GmbH. All rights reserved.
4 *
5 * Authors:
6 * Alexander Graf <agraf@suse.de>
7 * Kevin Wolf <mail@kevin-wolf.de>
8 */
9
10 #include <linux/kvm_host.h>
11
12 #include <asm/kvm_ppc.h>
13 #include <asm/kvm_book3s.h>
14 #include <asm/book3s/64/mmu-hash.h>
15 #include <asm/machdep.h>
16 #include <asm/mmu_context.h>
17 #include <asm/hw_irq.h>
18 #include "trace_pr.h"
19 #include "book3s.h"
20
21 #define PTE_SIZE 12
22
kvmppc_mmu_invalidate_pte(struct kvm_vcpu * vcpu,struct hpte_cache * pte)23 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
24 {
25 mmu_hash_ops.hpte_invalidate(pte->slot, pte->host_vpn,
26 pte->pagesize, pte->pagesize,
27 MMU_SEGSIZE_256M, false);
28 }
29
30 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
31 * a hash, so we don't waste cycles on looping */
kvmppc_sid_hash(struct kvm_vcpu * vcpu,u64 gvsid)32 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
33 {
34 return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
35 ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
36 ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
37 ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
38 ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
39 ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
40 ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
41 ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
42 }
43
44
find_sid_vsid(struct kvm_vcpu * vcpu,u64 gvsid)45 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
46 {
47 struct kvmppc_sid_map *map;
48 u16 sid_map_mask;
49
50 if (kvmppc_get_msr(vcpu) & MSR_PR)
51 gvsid |= VSID_PR;
52
53 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
54 map = &to_book3s(vcpu)->sid_map[sid_map_mask];
55 if (map->valid && (map->guest_vsid == gvsid)) {
56 trace_kvm_book3s_slb_found(gvsid, map->host_vsid);
57 return map;
58 }
59
60 map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
61 if (map->valid && (map->guest_vsid == gvsid)) {
62 trace_kvm_book3s_slb_found(gvsid, map->host_vsid);
63 return map;
64 }
65
66 trace_kvm_book3s_slb_fail(sid_map_mask, gvsid);
67 return NULL;
68 }
69
kvmppc_mmu_map_page(struct kvm_vcpu * vcpu,struct kvmppc_pte * orig_pte,bool iswrite)70 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
71 bool iswrite)
72 {
73 unsigned long vpn;
74 kvm_pfn_t hpaddr;
75 ulong hash, hpteg;
76 u64 vsid;
77 int ret;
78 int rflags = 0x192;
79 int vflags = 0;
80 int attempt = 0;
81 struct kvmppc_sid_map *map;
82 int r = 0;
83 int hpsize = MMU_PAGE_4K;
84 bool writable;
85 unsigned long mmu_seq;
86 struct kvm *kvm = vcpu->kvm;
87 struct hpte_cache *cpte;
88 unsigned long gfn = orig_pte->raddr >> PAGE_SHIFT;
89 unsigned long pfn;
90
91 /* used to check for invalidations in progress */
92 mmu_seq = kvm->mmu_notifier_seq;
93 smp_rmb();
94
95 /* Get host physical address for gpa */
96 pfn = kvmppc_gpa_to_pfn(vcpu, orig_pte->raddr, iswrite, &writable);
97 if (is_error_noslot_pfn(pfn)) {
98 printk(KERN_INFO "Couldn't get guest page for gpa %lx!\n",
99 orig_pte->raddr);
100 r = -EINVAL;
101 goto out;
102 }
103 hpaddr = pfn << PAGE_SHIFT;
104
105 /* and write the mapping ea -> hpa into the pt */
106 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
107 map = find_sid_vsid(vcpu, vsid);
108 if (!map) {
109 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr);
110 WARN_ON(ret < 0);
111 map = find_sid_vsid(vcpu, vsid);
112 }
113 if (!map) {
114 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n",
115 vsid, orig_pte->eaddr);
116 WARN_ON(true);
117 r = -EINVAL;
118 goto out;
119 }
120
121 vpn = hpt_vpn(orig_pte->eaddr, map->host_vsid, MMU_SEGSIZE_256M);
122
123 kvm_set_pfn_accessed(pfn);
124 if (!orig_pte->may_write || !writable)
125 rflags |= PP_RXRX;
126 else {
127 mark_page_dirty(vcpu->kvm, gfn);
128 kvm_set_pfn_dirty(pfn);
129 }
130
131 if (!orig_pte->may_execute)
132 rflags |= HPTE_R_N;
133 else
134 kvmppc_mmu_flush_icache(pfn);
135
136 rflags = (rflags & ~HPTE_R_WIMG) | orig_pte->wimg;
137
138 /*
139 * Use 64K pages if possible; otherwise, on 64K page kernels,
140 * we need to transfer 4 more bits from guest real to host real addr.
141 */
142 if (vsid & VSID_64K)
143 hpsize = MMU_PAGE_64K;
144 else
145 hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK);
146
147 hash = hpt_hash(vpn, mmu_psize_defs[hpsize].shift, MMU_SEGSIZE_256M);
148
149 cpte = kvmppc_mmu_hpte_cache_next(vcpu);
150
151 spin_lock(&kvm->mmu_lock);
152 if (!cpte || mmu_notifier_retry(kvm, mmu_seq)) {
153 r = -EAGAIN;
154 goto out_unlock;
155 }
156
157 map_again:
158 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
159
160 /* In case we tried normal mapping already, let's nuke old entries */
161 if (attempt > 1)
162 if (mmu_hash_ops.hpte_remove(hpteg) < 0) {
163 r = -1;
164 goto out_unlock;
165 }
166
167 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, hpaddr, rflags, vflags,
168 hpsize, hpsize, MMU_SEGSIZE_256M);
169
170 if (ret == -1) {
171 /* If we couldn't map a primary PTE, try a secondary */
172 hash = ~hash;
173 vflags ^= HPTE_V_SECONDARY;
174 attempt++;
175 goto map_again;
176 } else if (ret < 0) {
177 r = -EIO;
178 goto out_unlock;
179 } else {
180 trace_kvm_book3s_64_mmu_map(rflags, hpteg,
181 vpn, hpaddr, orig_pte);
182
183 /*
184 * The mmu_hash_ops code may give us a secondary entry even
185 * though we asked for a primary. Fix up.
186 */
187 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) {
188 hash = ~hash;
189 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
190 }
191
192 cpte->slot = hpteg + (ret & 7);
193 cpte->host_vpn = vpn;
194 cpte->pte = *orig_pte;
195 cpte->pfn = pfn;
196 cpte->pagesize = hpsize;
197
198 kvmppc_mmu_hpte_cache_map(vcpu, cpte);
199 cpte = NULL;
200 }
201
202 out_unlock:
203 spin_unlock(&kvm->mmu_lock);
204 kvm_release_pfn_clean(pfn);
205 if (cpte)
206 kvmppc_mmu_hpte_cache_free(cpte);
207
208 out:
209 return r;
210 }
211
kvmppc_mmu_unmap_page(struct kvm_vcpu * vcpu,struct kvmppc_pte * pte)212 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
213 {
214 u64 mask = 0xfffffffffULL;
215 u64 vsid;
216
217 vcpu->arch.mmu.esid_to_vsid(vcpu, pte->eaddr >> SID_SHIFT, &vsid);
218 if (vsid & VSID_64K)
219 mask = 0xffffffff0ULL;
220 kvmppc_mmu_pte_vflush(vcpu, pte->vpage, mask);
221 }
222
create_sid_map(struct kvm_vcpu * vcpu,u64 gvsid)223 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
224 {
225 unsigned long vsid_bits = VSID_BITS_65_256M;
226 struct kvmppc_sid_map *map;
227 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
228 u16 sid_map_mask;
229 static int backwards_map = 0;
230
231 if (kvmppc_get_msr(vcpu) & MSR_PR)
232 gvsid |= VSID_PR;
233
234 /* We might get collisions that trap in preceding order, so let's
235 map them differently */
236
237 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
238 if (backwards_map)
239 sid_map_mask = SID_MAP_MASK - sid_map_mask;
240
241 map = &to_book3s(vcpu)->sid_map[sid_map_mask];
242
243 /* Make sure we're taking the other map next time */
244 backwards_map = !backwards_map;
245
246 /* Uh-oh ... out of mappings. Let's flush! */
247 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) {
248 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first;
249 memset(vcpu_book3s->sid_map, 0,
250 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
251 kvmppc_mmu_pte_flush(vcpu, 0, 0);
252 kvmppc_mmu_flush_segments(vcpu);
253 }
254
255 if (mmu_has_feature(MMU_FTR_68_BIT_VA))
256 vsid_bits = VSID_BITS_256M;
257
258 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++,
259 VSID_MULTIPLIER_256M, vsid_bits);
260
261 map->guest_vsid = gvsid;
262 map->valid = true;
263
264 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid);
265
266 return map;
267 }
268
kvmppc_mmu_next_segment(struct kvm_vcpu * vcpu,ulong esid)269 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid)
270 {
271 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
272 int i;
273 int max_slb_size = 64;
274 int found_inval = -1;
275 int r;
276
277 /* Are we overwriting? */
278 for (i = 0; i < svcpu->slb_max; i++) {
279 if (!(svcpu->slb[i].esid & SLB_ESID_V))
280 found_inval = i;
281 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) {
282 r = i;
283 goto out;
284 }
285 }
286
287 /* Found a spare entry that was invalidated before */
288 if (found_inval >= 0) {
289 r = found_inval;
290 goto out;
291 }
292
293 /* No spare invalid entry, so create one */
294
295 if (mmu_slb_size < 64)
296 max_slb_size = mmu_slb_size;
297
298 /* Overflowing -> purge */
299 if ((svcpu->slb_max) == max_slb_size)
300 kvmppc_mmu_flush_segments(vcpu);
301
302 r = svcpu->slb_max;
303 svcpu->slb_max++;
304
305 out:
306 svcpu_put(svcpu);
307 return r;
308 }
309
kvmppc_mmu_map_segment(struct kvm_vcpu * vcpu,ulong eaddr)310 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
311 {
312 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
313 u64 esid = eaddr >> SID_SHIFT;
314 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V;
315 u64 slb_vsid = SLB_VSID_USER;
316 u64 gvsid;
317 int slb_index;
318 struct kvmppc_sid_map *map;
319 int r = 0;
320
321 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK);
322
323 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
324 /* Invalidate an entry */
325 svcpu->slb[slb_index].esid = 0;
326 r = -ENOENT;
327 goto out;
328 }
329
330 map = find_sid_vsid(vcpu, gvsid);
331 if (!map)
332 map = create_sid_map(vcpu, gvsid);
333
334 map->guest_esid = esid;
335
336 slb_vsid |= (map->host_vsid << 12);
337 slb_vsid &= ~SLB_VSID_KP;
338 slb_esid |= slb_index;
339
340 #ifdef CONFIG_PPC_64K_PAGES
341 /* Set host segment base page size to 64K if possible */
342 if (gvsid & VSID_64K)
343 slb_vsid |= mmu_psize_defs[MMU_PAGE_64K].sllp;
344 #endif
345
346 svcpu->slb[slb_index].esid = slb_esid;
347 svcpu->slb[slb_index].vsid = slb_vsid;
348
349 trace_kvm_book3s_slbmte(slb_vsid, slb_esid);
350
351 out:
352 svcpu_put(svcpu);
353 return r;
354 }
355
kvmppc_mmu_flush_segment(struct kvm_vcpu * vcpu,ulong ea,ulong seg_size)356 void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong ea, ulong seg_size)
357 {
358 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
359 ulong seg_mask = -seg_size;
360 int i;
361
362 for (i = 0; i < svcpu->slb_max; i++) {
363 if ((svcpu->slb[i].esid & SLB_ESID_V) &&
364 (svcpu->slb[i].esid & seg_mask) == ea) {
365 /* Invalidate this entry */
366 svcpu->slb[i].esid = 0;
367 }
368 }
369
370 svcpu_put(svcpu);
371 }
372
kvmppc_mmu_flush_segments(struct kvm_vcpu * vcpu)373 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
374 {
375 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
376 svcpu->slb_max = 0;
377 svcpu->slb[0].esid = 0;
378 svcpu_put(svcpu);
379 }
380
kvmppc_mmu_destroy_pr(struct kvm_vcpu * vcpu)381 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
382 {
383 kvmppc_mmu_hpte_destroy(vcpu);
384 __destroy_context(to_book3s(vcpu)->context_id[0]);
385 }
386
kvmppc_mmu_init_pr(struct kvm_vcpu * vcpu)387 int kvmppc_mmu_init_pr(struct kvm_vcpu *vcpu)
388 {
389 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
390 int err;
391
392 err = hash__alloc_context_id();
393 if (err < 0)
394 return -1;
395 vcpu3s->context_id[0] = err;
396
397 vcpu3s->proto_vsid_max = ((u64)(vcpu3s->context_id[0] + 1)
398 << ESID_BITS) - 1;
399 vcpu3s->proto_vsid_first = (u64)vcpu3s->context_id[0] << ESID_BITS;
400 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first;
401
402 kvmppc_mmu_hpte_init(vcpu);
403
404 return 0;
405 }
406
