1 /*
2 * Copyright (C) 2009 SUSE Linux Products GmbH. All rights reserved.
3 *
4 * Authors:
5 * Alexander Graf <agraf@suse.de>
6 * Kevin Wolf <mail@kevin-wolf.de>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License, version 2, as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20 */
21
22 #include <linux/kvm_host.h>
23
24 #include <asm/kvm_ppc.h>
25 #include <asm/kvm_book3s.h>
26 #include <asm/book3s/64/mmu-hash.h>
27 #include <asm/machdep.h>
28 #include <asm/mmu_context.h>
29 #include <asm/hw_irq.h>
30 #include "trace_pr.h"
31 #include "book3s.h"
32
33 #define PTE_SIZE 12
34
kvmppc_mmu_invalidate_pte(struct kvm_vcpu * vcpu,struct hpte_cache * pte)35 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
36 {
37 mmu_hash_ops.hpte_invalidate(pte->slot, pte->host_vpn,
38 pte->pagesize, pte->pagesize,
39 MMU_SEGSIZE_256M, false);
40 }
41
42 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
43 * a hash, so we don't waste cycles on looping */
kvmppc_sid_hash(struct kvm_vcpu * vcpu,u64 gvsid)44 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
45 {
46 return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
47 ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
48 ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
49 ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
50 ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
51 ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
52 ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
53 ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
54 }
55
56
find_sid_vsid(struct kvm_vcpu * vcpu,u64 gvsid)57 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
58 {
59 struct kvmppc_sid_map *map;
60 u16 sid_map_mask;
61
62 if (kvmppc_get_msr(vcpu) & MSR_PR)
63 gvsid |= VSID_PR;
64
65 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
66 map = &to_book3s(vcpu)->sid_map[sid_map_mask];
67 if (map->valid && (map->guest_vsid == gvsid)) {
68 trace_kvm_book3s_slb_found(gvsid, map->host_vsid);
69 return map;
70 }
71
72 map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
73 if (map->valid && (map->guest_vsid == gvsid)) {
74 trace_kvm_book3s_slb_found(gvsid, map->host_vsid);
75 return map;
76 }
77
78 trace_kvm_book3s_slb_fail(sid_map_mask, gvsid);
79 return NULL;
80 }
81
kvmppc_mmu_map_page(struct kvm_vcpu * vcpu,struct kvmppc_pte * orig_pte,bool iswrite)82 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
83 bool iswrite)
84 {
85 unsigned long vpn;
86 kvm_pfn_t hpaddr;
87 ulong hash, hpteg;
88 u64 vsid;
89 int ret;
90 int rflags = 0x192;
91 int vflags = 0;
92 int attempt = 0;
93 struct kvmppc_sid_map *map;
94 int r = 0;
95 int hpsize = MMU_PAGE_4K;
96 bool writable;
97 unsigned long mmu_seq;
98 struct kvm *kvm = vcpu->kvm;
99 struct hpte_cache *cpte;
100 unsigned long gfn = orig_pte->raddr >> PAGE_SHIFT;
101 unsigned long pfn;
102
103 /* used to check for invalidations in progress */
104 mmu_seq = kvm->mmu_notifier_seq;
105 smp_rmb();
106
107 /* Get host physical address for gpa */
108 pfn = kvmppc_gpa_to_pfn(vcpu, orig_pte->raddr, iswrite, &writable);
109 if (is_error_noslot_pfn(pfn)) {
110 printk(KERN_INFO "Couldn't get guest page for gpa %lx!\n",
111 orig_pte->raddr);
112 r = -EINVAL;
113 goto out;
114 }
115 hpaddr = pfn << PAGE_SHIFT;
116
117 /* and write the mapping ea -> hpa into the pt */
118 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
119 map = find_sid_vsid(vcpu, vsid);
120 if (!map) {
121 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr);
122 WARN_ON(ret < 0);
123 map = find_sid_vsid(vcpu, vsid);
124 }
125 if (!map) {
126 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n",
127 vsid, orig_pte->eaddr);
128 WARN_ON(true);
129 r = -EINVAL;
130 goto out;
131 }
132
133 vpn = hpt_vpn(orig_pte->eaddr, map->host_vsid, MMU_SEGSIZE_256M);
134
135 kvm_set_pfn_accessed(pfn);
136 if (!orig_pte->may_write || !writable)
137 rflags |= PP_RXRX;
138 else {
139 mark_page_dirty(vcpu->kvm, gfn);
140 kvm_set_pfn_dirty(pfn);
141 }
142
143 if (!orig_pte->may_execute)
144 rflags |= HPTE_R_N;
145 else
146 kvmppc_mmu_flush_icache(pfn);
147
148 /*
149 * Use 64K pages if possible; otherwise, on 64K page kernels,
150 * we need to transfer 4 more bits from guest real to host real addr.
151 */
152 if (vsid & VSID_64K)
153 hpsize = MMU_PAGE_64K;
154 else
155 hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK);
156
157 hash = hpt_hash(vpn, mmu_psize_defs[hpsize].shift, MMU_SEGSIZE_256M);
158
159 cpte = kvmppc_mmu_hpte_cache_next(vcpu);
160
161 spin_lock(&kvm->mmu_lock);
162 if (!cpte || mmu_notifier_retry(kvm, mmu_seq)) {
163 r = -EAGAIN;
164 goto out_unlock;
165 }
166
167 map_again:
168 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
169
170 /* In case we tried normal mapping already, let's nuke old entries */
171 if (attempt > 1)
172 if (mmu_hash_ops.hpte_remove(hpteg) < 0) {
173 r = -1;
174 goto out_unlock;
175 }
176
177 ret = mmu_hash_ops.hpte_insert(hpteg, vpn, hpaddr, rflags, vflags,
178 hpsize, hpsize, MMU_SEGSIZE_256M);
179
180 if (ret == -1) {
181 /* If we couldn't map a primary PTE, try a secondary */
182 hash = ~hash;
183 vflags ^= HPTE_V_SECONDARY;
184 attempt++;
185 goto map_again;
186 } else if (ret < 0) {
187 r = -EIO;
188 goto out_unlock;
189 } else {
190 trace_kvm_book3s_64_mmu_map(rflags, hpteg,
191 vpn, hpaddr, orig_pte);
192
193 /*
194 * The mmu_hash_ops code may give us a secondary entry even
195 * though we asked for a primary. Fix up.
196 */
197 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) {
198 hash = ~hash;
199 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
200 }
201
202 cpte->slot = hpteg + (ret & 7);
203 cpte->host_vpn = vpn;
204 cpte->pte = *orig_pte;
205 cpte->pfn = pfn;
206 cpte->pagesize = hpsize;
207
208 kvmppc_mmu_hpte_cache_map(vcpu, cpte);
209 cpte = NULL;
210 }
211
212 out_unlock:
213 spin_unlock(&kvm->mmu_lock);
214 kvm_release_pfn_clean(pfn);
215 if (cpte)
216 kvmppc_mmu_hpte_cache_free(cpte);
217
218 out:
219 return r;
220 }
221
kvmppc_mmu_unmap_page(struct kvm_vcpu * vcpu,struct kvmppc_pte * pte)222 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
223 {
224 u64 mask = 0xfffffffffULL;
225 u64 vsid;
226
227 vcpu->arch.mmu.esid_to_vsid(vcpu, pte->eaddr >> SID_SHIFT, &vsid);
228 if (vsid & VSID_64K)
229 mask = 0xffffffff0ULL;
230 kvmppc_mmu_pte_vflush(vcpu, pte->vpage, mask);
231 }
232
create_sid_map(struct kvm_vcpu * vcpu,u64 gvsid)233 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
234 {
235 struct kvmppc_sid_map *map;
236 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
237 u16 sid_map_mask;
238 static int backwards_map = 0;
239
240 if (kvmppc_get_msr(vcpu) & MSR_PR)
241 gvsid |= VSID_PR;
242
243 /* We might get collisions that trap in preceding order, so let's
244 map them differently */
245
246 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
247 if (backwards_map)
248 sid_map_mask = SID_MAP_MASK - sid_map_mask;
249
250 map = &to_book3s(vcpu)->sid_map[sid_map_mask];
251
252 /* Make sure we're taking the other map next time */
253 backwards_map = !backwards_map;
254
255 /* Uh-oh ... out of mappings. Let's flush! */
256 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) {
257 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first;
258 memset(vcpu_book3s->sid_map, 0,
259 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
260 kvmppc_mmu_pte_flush(vcpu, 0, 0);
261 kvmppc_mmu_flush_segments(vcpu);
262 }
263 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M);
264
265 map->guest_vsid = gvsid;
266 map->valid = true;
267
268 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid);
269
270 return map;
271 }
272
kvmppc_mmu_next_segment(struct kvm_vcpu * vcpu,ulong esid)273 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid)
274 {
275 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
276 int i;
277 int max_slb_size = 64;
278 int found_inval = -1;
279 int r;
280
281 /* Are we overwriting? */
282 for (i = 0; i < svcpu->slb_max; i++) {
283 if (!(svcpu->slb[i].esid & SLB_ESID_V))
284 found_inval = i;
285 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) {
286 r = i;
287 goto out;
288 }
289 }
290
291 /* Found a spare entry that was invalidated before */
292 if (found_inval >= 0) {
293 r = found_inval;
294 goto out;
295 }
296
297 /* No spare invalid entry, so create one */
298
299 if (mmu_slb_size < 64)
300 max_slb_size = mmu_slb_size;
301
302 /* Overflowing -> purge */
303 if ((svcpu->slb_max) == max_slb_size)
304 kvmppc_mmu_flush_segments(vcpu);
305
306 r = svcpu->slb_max;
307 svcpu->slb_max++;
308
309 out:
310 svcpu_put(svcpu);
311 return r;
312 }
313
kvmppc_mmu_map_segment(struct kvm_vcpu * vcpu,ulong eaddr)314 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
315 {
316 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
317 u64 esid = eaddr >> SID_SHIFT;
318 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V;
319 u64 slb_vsid = SLB_VSID_USER;
320 u64 gvsid;
321 int slb_index;
322 struct kvmppc_sid_map *map;
323 int r = 0;
324
325 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK);
326
327 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
328 /* Invalidate an entry */
329 svcpu->slb[slb_index].esid = 0;
330 r = -ENOENT;
331 goto out;
332 }
333
334 map = find_sid_vsid(vcpu, gvsid);
335 if (!map)
336 map = create_sid_map(vcpu, gvsid);
337
338 map->guest_esid = esid;
339
340 slb_vsid |= (map->host_vsid << 12);
341 slb_vsid &= ~SLB_VSID_KP;
342 slb_esid |= slb_index;
343
344 #ifdef CONFIG_PPC_64K_PAGES
345 /* Set host segment base page size to 64K if possible */
346 if (gvsid & VSID_64K)
347 slb_vsid |= mmu_psize_defs[MMU_PAGE_64K].sllp;
348 #endif
349
350 svcpu->slb[slb_index].esid = slb_esid;
351 svcpu->slb[slb_index].vsid = slb_vsid;
352
353 trace_kvm_book3s_slbmte(slb_vsid, slb_esid);
354
355 out:
356 svcpu_put(svcpu);
357 return r;
358 }
359
kvmppc_mmu_flush_segment(struct kvm_vcpu * vcpu,ulong ea,ulong seg_size)360 void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong ea, ulong seg_size)
361 {
362 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
363 ulong seg_mask = -seg_size;
364 int i;
365
366 for (i = 0; i < svcpu->slb_max; i++) {
367 if ((svcpu->slb[i].esid & SLB_ESID_V) &&
368 (svcpu->slb[i].esid & seg_mask) == ea) {
369 /* Invalidate this entry */
370 svcpu->slb[i].esid = 0;
371 }
372 }
373
374 svcpu_put(svcpu);
375 }
376
kvmppc_mmu_flush_segments(struct kvm_vcpu * vcpu)377 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
378 {
379 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
380 svcpu->slb_max = 0;
381 svcpu->slb[0].esid = 0;
382 svcpu_put(svcpu);
383 }
384
kvmppc_mmu_destroy_pr(struct kvm_vcpu * vcpu)385 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
386 {
387 kvmppc_mmu_hpte_destroy(vcpu);
388 __destroy_context(to_book3s(vcpu)->context_id[0]);
389 }
390
kvmppc_mmu_init(struct kvm_vcpu * vcpu)391 int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
392 {
393 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
394 int err;
395
396 err = __init_new_context();
397 if (err < 0)
398 return -1;
399 vcpu3s->context_id[0] = err;
400
401 vcpu3s->proto_vsid_max = ((u64)(vcpu3s->context_id[0] + 1)
402 << ESID_BITS) - 1;
403 vcpu3s->proto_vsid_first = (u64)vcpu3s->context_id[0] << ESID_BITS;
404 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first;
405
406 kvmppc_mmu_hpte_init(vcpu);
407
408 return 0;
409 }
410