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 35 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte) 36 { 37 ppc_md.hpte_invalidate(pte->slot, pte->host_vpn, 38 pte->pagesize, pte->pagesize, MMU_SEGSIZE_256M, 39 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 */ 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 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 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 (ppc_md.hpte_remove(hpteg) < 0) { 173 r = -1; 174 goto out_unlock; 175 } 176 177 ret = ppc_md.hpte_insert(hpteg, vpn, hpaddr, rflags, vflags, 178 hpsize, hpsize, MMU_SEGSIZE_256M); 179 180 if (ret < 0) { 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 { 187 trace_kvm_book3s_64_mmu_map(rflags, hpteg, 188 vpn, hpaddr, orig_pte); 189 190 /* The ppc_md code may give us a secondary entry even though we 191 asked for a primary. Fix up. */ 192 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) { 193 hash = ~hash; 194 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 195 } 196 197 cpte->slot = hpteg + (ret & 7); 198 cpte->host_vpn = vpn; 199 cpte->pte = *orig_pte; 200 cpte->pfn = pfn; 201 cpte->pagesize = hpsize; 202 203 kvmppc_mmu_hpte_cache_map(vcpu, cpte); 204 cpte = NULL; 205 } 206 207 out_unlock: 208 spin_unlock(&kvm->mmu_lock); 209 kvm_release_pfn_clean(pfn); 210 if (cpte) 211 kvmppc_mmu_hpte_cache_free(cpte); 212 213 out: 214 return r; 215 } 216 217 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte) 218 { 219 u64 mask = 0xfffffffffULL; 220 u64 vsid; 221 222 vcpu->arch.mmu.esid_to_vsid(vcpu, pte->eaddr >> SID_SHIFT, &vsid); 223 if (vsid & VSID_64K) 224 mask = 0xffffffff0ULL; 225 kvmppc_mmu_pte_vflush(vcpu, pte->vpage, mask); 226 } 227 228 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) 229 { 230 struct kvmppc_sid_map *map; 231 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); 232 u16 sid_map_mask; 233 static int backwards_map = 0; 234 235 if (kvmppc_get_msr(vcpu) & MSR_PR) 236 gvsid |= VSID_PR; 237 238 /* We might get collisions that trap in preceding order, so let's 239 map them differently */ 240 241 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 242 if (backwards_map) 243 sid_map_mask = SID_MAP_MASK - sid_map_mask; 244 245 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 246 247 /* Make sure we're taking the other map next time */ 248 backwards_map = !backwards_map; 249 250 /* Uh-oh ... out of mappings. Let's flush! */ 251 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) { 252 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first; 253 memset(vcpu_book3s->sid_map, 0, 254 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM); 255 kvmppc_mmu_pte_flush(vcpu, 0, 0); 256 kvmppc_mmu_flush_segments(vcpu); 257 } 258 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M); 259 260 map->guest_vsid = gvsid; 261 map->valid = true; 262 263 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid); 264 265 return map; 266 } 267 268 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) 269 { 270 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 271 int i; 272 int max_slb_size = 64; 273 int found_inval = -1; 274 int r; 275 276 /* Are we overwriting? */ 277 for (i = 0; i < svcpu->slb_max; i++) { 278 if (!(svcpu->slb[i].esid & SLB_ESID_V)) 279 found_inval = i; 280 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) { 281 r = i; 282 goto out; 283 } 284 } 285 286 /* Found a spare entry that was invalidated before */ 287 if (found_inval >= 0) { 288 r = found_inval; 289 goto out; 290 } 291 292 /* No spare invalid entry, so create one */ 293 294 if (mmu_slb_size < 64) 295 max_slb_size = mmu_slb_size; 296 297 /* Overflowing -> purge */ 298 if ((svcpu->slb_max) == max_slb_size) 299 kvmppc_mmu_flush_segments(vcpu); 300 301 r = svcpu->slb_max; 302 svcpu->slb_max++; 303 304 out: 305 svcpu_put(svcpu); 306 return r; 307 } 308 309 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) 310 { 311 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 312 u64 esid = eaddr >> SID_SHIFT; 313 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V; 314 u64 slb_vsid = SLB_VSID_USER; 315 u64 gvsid; 316 int slb_index; 317 struct kvmppc_sid_map *map; 318 int r = 0; 319 320 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); 321 322 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { 323 /* Invalidate an entry */ 324 svcpu->slb[slb_index].esid = 0; 325 r = -ENOENT; 326 goto out; 327 } 328 329 map = find_sid_vsid(vcpu, gvsid); 330 if (!map) 331 map = create_sid_map(vcpu, gvsid); 332 333 map->guest_esid = esid; 334 335 slb_vsid |= (map->host_vsid << 12); 336 slb_vsid &= ~SLB_VSID_KP; 337 slb_esid |= slb_index; 338 339 #ifdef CONFIG_PPC_64K_PAGES 340 /* Set host segment base page size to 64K if possible */ 341 if (gvsid & VSID_64K) 342 slb_vsid |= mmu_psize_defs[MMU_PAGE_64K].sllp; 343 #endif 344 345 svcpu->slb[slb_index].esid = slb_esid; 346 svcpu->slb[slb_index].vsid = slb_vsid; 347 348 trace_kvm_book3s_slbmte(slb_vsid, slb_esid); 349 350 out: 351 svcpu_put(svcpu); 352 return r; 353 } 354 355 void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong ea, ulong seg_size) 356 { 357 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 358 ulong seg_mask = -seg_size; 359 int i; 360 361 for (i = 0; i < svcpu->slb_max; i++) { 362 if ((svcpu->slb[i].esid & SLB_ESID_V) && 363 (svcpu->slb[i].esid & seg_mask) == ea) { 364 /* Invalidate this entry */ 365 svcpu->slb[i].esid = 0; 366 } 367 } 368 369 svcpu_put(svcpu); 370 } 371 372 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) 373 { 374 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 375 svcpu->slb_max = 0; 376 svcpu->slb[0].esid = 0; 377 svcpu_put(svcpu); 378 } 379 380 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu) 381 { 382 kvmppc_mmu_hpte_destroy(vcpu); 383 __destroy_context(to_book3s(vcpu)->context_id[0]); 384 } 385 386 int kvmppc_mmu_init(struct kvm_vcpu *vcpu) 387 { 388 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu); 389 int err; 390 391 err = __init_new_context(); 392 if (err < 0) 393 return -1; 394 vcpu3s->context_id[0] = err; 395 396 vcpu3s->proto_vsid_max = ((u64)(vcpu3s->context_id[0] + 1) 397 << ESID_BITS) - 1; 398 vcpu3s->proto_vsid_first = (u64)vcpu3s->context_id[0] << ESID_BITS; 399 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first; 400 401 kvmppc_mmu_hpte_init(vcpu); 402 403 return 0; 404 } 405