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/mmu-hash64.h> 27 #include <asm/machdep.h> 28 #include <asm/mmu_context.h> 29 #include <asm/hw_irq.h> 30 #include "trace_pr.h" 31 32 #define PTE_SIZE 12 33 34 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte) 35 { 36 ppc_md.hpte_invalidate(pte->slot, pte->host_vpn, 37 pte->pagesize, pte->pagesize, MMU_SEGSIZE_256M, 38 false); 39 } 40 41 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using 42 * a hash, so we don't waste cycles on looping */ 43 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid) 44 { 45 return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^ 46 ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^ 47 ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^ 48 ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^ 49 ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^ 50 ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^ 51 ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^ 52 ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK)); 53 } 54 55 56 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid) 57 { 58 struct kvmppc_sid_map *map; 59 u16 sid_map_mask; 60 61 if (kvmppc_get_msr(vcpu) & MSR_PR) 62 gvsid |= VSID_PR; 63 64 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 65 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 66 if (map->valid && (map->guest_vsid == gvsid)) { 67 trace_kvm_book3s_slb_found(gvsid, map->host_vsid); 68 return map; 69 } 70 71 map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask]; 72 if (map->valid && (map->guest_vsid == gvsid)) { 73 trace_kvm_book3s_slb_found(gvsid, map->host_vsid); 74 return map; 75 } 76 77 trace_kvm_book3s_slb_fail(sid_map_mask, gvsid); 78 return NULL; 79 } 80 81 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte, 82 bool iswrite) 83 { 84 unsigned long vpn; 85 pfn_t hpaddr; 86 ulong hash, hpteg; 87 u64 vsid; 88 int ret; 89 int rflags = 0x192; 90 int vflags = 0; 91 int attempt = 0; 92 struct kvmppc_sid_map *map; 93 int r = 0; 94 int hpsize = MMU_PAGE_4K; 95 bool writable; 96 unsigned long mmu_seq; 97 struct kvm *kvm = vcpu->kvm; 98 struct hpte_cache *cpte; 99 unsigned long gfn = orig_pte->raddr >> PAGE_SHIFT; 100 unsigned long pfn; 101 102 /* used to check for invalidations in progress */ 103 mmu_seq = kvm->mmu_notifier_seq; 104 smp_rmb(); 105 106 /* Get host physical address for gpa */ 107 pfn = kvmppc_gpa_to_pfn(vcpu, orig_pte->raddr, iswrite, &writable); 108 if (is_error_noslot_pfn(pfn)) { 109 printk(KERN_INFO "Couldn't get guest page for gpa %lx!\n", 110 orig_pte->raddr); 111 r = -EINVAL; 112 goto out; 113 } 114 hpaddr = pfn << PAGE_SHIFT; 115 116 /* and write the mapping ea -> hpa into the pt */ 117 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid); 118 map = find_sid_vsid(vcpu, vsid); 119 if (!map) { 120 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr); 121 WARN_ON(ret < 0); 122 map = find_sid_vsid(vcpu, vsid); 123 } 124 if (!map) { 125 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n", 126 vsid, orig_pte->eaddr); 127 WARN_ON(true); 128 r = -EINVAL; 129 goto out; 130 } 131 132 vpn = hpt_vpn(orig_pte->eaddr, map->host_vsid, MMU_SEGSIZE_256M); 133 134 kvm_set_pfn_accessed(pfn); 135 if (!orig_pte->may_write || !writable) 136 rflags |= PP_RXRX; 137 else { 138 mark_page_dirty(vcpu->kvm, gfn); 139 kvm_set_pfn_dirty(pfn); 140 } 141 142 if (!orig_pte->may_execute) 143 rflags |= HPTE_R_N; 144 else 145 kvmppc_mmu_flush_icache(pfn); 146 147 /* 148 * Use 64K pages if possible; otherwise, on 64K page kernels, 149 * we need to transfer 4 more bits from guest real to host real addr. 150 */ 151 if (vsid & VSID_64K) 152 hpsize = MMU_PAGE_64K; 153 else 154 hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK); 155 156 hash = hpt_hash(vpn, mmu_psize_defs[hpsize].shift, MMU_SEGSIZE_256M); 157 158 cpte = kvmppc_mmu_hpte_cache_next(vcpu); 159 160 spin_lock(&kvm->mmu_lock); 161 if (!cpte || mmu_notifier_retry(kvm, mmu_seq)) { 162 r = -EAGAIN; 163 goto out_unlock; 164 } 165 166 map_again: 167 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 168 169 /* In case we tried normal mapping already, let's nuke old entries */ 170 if (attempt > 1) 171 if (ppc_md.hpte_remove(hpteg) < 0) { 172 r = -1; 173 goto out_unlock; 174 } 175 176 ret = ppc_md.hpte_insert(hpteg, vpn, hpaddr, rflags, vflags, 177 hpsize, hpsize, MMU_SEGSIZE_256M); 178 179 if (ret < 0) { 180 /* If we couldn't map a primary PTE, try a secondary */ 181 hash = ~hash; 182 vflags ^= HPTE_V_SECONDARY; 183 attempt++; 184 goto map_again; 185 } else { 186 trace_kvm_book3s_64_mmu_map(rflags, hpteg, 187 vpn, hpaddr, orig_pte); 188 189 /* The ppc_md code may give us a secondary entry even though we 190 asked for a primary. Fix up. */ 191 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) { 192 hash = ~hash; 193 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 194 } 195 196 cpte->slot = hpteg + (ret & 7); 197 cpte->host_vpn = vpn; 198 cpte->pte = *orig_pte; 199 cpte->pfn = pfn; 200 cpte->pagesize = hpsize; 201 202 kvmppc_mmu_hpte_cache_map(vcpu, cpte); 203 cpte = NULL; 204 } 205 206 out_unlock: 207 spin_unlock(&kvm->mmu_lock); 208 kvm_release_pfn_clean(pfn); 209 if (cpte) 210 kvmppc_mmu_hpte_cache_free(cpte); 211 212 out: 213 return r; 214 } 215 216 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte) 217 { 218 u64 mask = 0xfffffffffULL; 219 u64 vsid; 220 221 vcpu->arch.mmu.esid_to_vsid(vcpu, pte->eaddr >> SID_SHIFT, &vsid); 222 if (vsid & VSID_64K) 223 mask = 0xffffffff0ULL; 224 kvmppc_mmu_pte_vflush(vcpu, pte->vpage, mask); 225 } 226 227 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) 228 { 229 struct kvmppc_sid_map *map; 230 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); 231 u16 sid_map_mask; 232 static int backwards_map = 0; 233 234 if (kvmppc_get_msr(vcpu) & MSR_PR) 235 gvsid |= VSID_PR; 236 237 /* We might get collisions that trap in preceding order, so let's 238 map them differently */ 239 240 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 241 if (backwards_map) 242 sid_map_mask = SID_MAP_MASK - sid_map_mask; 243 244 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 245 246 /* Make sure we're taking the other map next time */ 247 backwards_map = !backwards_map; 248 249 /* Uh-oh ... out of mappings. Let's flush! */ 250 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) { 251 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first; 252 memset(vcpu_book3s->sid_map, 0, 253 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM); 254 kvmppc_mmu_pte_flush(vcpu, 0, 0); 255 kvmppc_mmu_flush_segments(vcpu); 256 } 257 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M); 258 259 map->guest_vsid = gvsid; 260 map->valid = true; 261 262 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid); 263 264 return map; 265 } 266 267 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) 268 { 269 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 270 int i; 271 int max_slb_size = 64; 272 int found_inval = -1; 273 int r; 274 275 /* Are we overwriting? */ 276 for (i = 0; i < svcpu->slb_max; i++) { 277 if (!(svcpu->slb[i].esid & SLB_ESID_V)) 278 found_inval = i; 279 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) { 280 r = i; 281 goto out; 282 } 283 } 284 285 /* Found a spare entry that was invalidated before */ 286 if (found_inval >= 0) { 287 r = found_inval; 288 goto out; 289 } 290 291 /* No spare invalid entry, so create one */ 292 293 if (mmu_slb_size < 64) 294 max_slb_size = mmu_slb_size; 295 296 /* Overflowing -> purge */ 297 if ((svcpu->slb_max) == max_slb_size) 298 kvmppc_mmu_flush_segments(vcpu); 299 300 r = svcpu->slb_max; 301 svcpu->slb_max++; 302 303 out: 304 svcpu_put(svcpu); 305 return r; 306 } 307 308 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) 309 { 310 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 311 u64 esid = eaddr >> SID_SHIFT; 312 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V; 313 u64 slb_vsid = SLB_VSID_USER; 314 u64 gvsid; 315 int slb_index; 316 struct kvmppc_sid_map *map; 317 int r = 0; 318 319 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); 320 321 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { 322 /* Invalidate an entry */ 323 svcpu->slb[slb_index].esid = 0; 324 r = -ENOENT; 325 goto out; 326 } 327 328 map = find_sid_vsid(vcpu, gvsid); 329 if (!map) 330 map = create_sid_map(vcpu, gvsid); 331 332 map->guest_esid = esid; 333 334 slb_vsid |= (map->host_vsid << 12); 335 slb_vsid &= ~SLB_VSID_KP; 336 slb_esid |= slb_index; 337 338 #ifdef CONFIG_PPC_64K_PAGES 339 /* Set host segment base page size to 64K if possible */ 340 if (gvsid & VSID_64K) 341 slb_vsid |= mmu_psize_defs[MMU_PAGE_64K].sllp; 342 #endif 343 344 svcpu->slb[slb_index].esid = slb_esid; 345 svcpu->slb[slb_index].vsid = slb_vsid; 346 347 trace_kvm_book3s_slbmte(slb_vsid, slb_esid); 348 349 out: 350 svcpu_put(svcpu); 351 return r; 352 } 353 354 void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong ea, ulong seg_size) 355 { 356 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 357 ulong seg_mask = -seg_size; 358 int i; 359 360 for (i = 0; i < svcpu->slb_max; i++) { 361 if ((svcpu->slb[i].esid & SLB_ESID_V) && 362 (svcpu->slb[i].esid & seg_mask) == ea) { 363 /* Invalidate this entry */ 364 svcpu->slb[i].esid = 0; 365 } 366 } 367 368 svcpu_put(svcpu); 369 } 370 371 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) 372 { 373 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 374 svcpu->slb_max = 0; 375 svcpu->slb[0].esid = 0; 376 svcpu_put(svcpu); 377 } 378 379 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu) 380 { 381 kvmppc_mmu_hpte_destroy(vcpu); 382 __destroy_context(to_book3s(vcpu)->context_id[0]); 383 } 384 385 int kvmppc_mmu_init(struct kvm_vcpu *vcpu) 386 { 387 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu); 388 int err; 389 390 err = __init_new_context(); 391 if (err < 0) 392 return -1; 393 vcpu3s->context_id[0] = err; 394 395 vcpu3s->proto_vsid_max = ((u64)(vcpu3s->context_id[0] + 1) 396 << ESID_BITS) - 1; 397 vcpu3s->proto_vsid_first = (u64)vcpu3s->context_id[0] << ESID_BITS; 398 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first; 399 400 kvmppc_mmu_hpte_init(vcpu); 401 402 return 0; 403 } 404