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