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.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_va, 37 MMU_PAGE_4K, 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 (vcpu->arch.shared->msr & 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 { 83 pfn_t hpaddr; 84 ulong hash, hpteg, va; 85 u64 vsid; 86 int ret; 87 int rflags = 0x192; 88 int vflags = 0; 89 int attempt = 0; 90 struct kvmppc_sid_map *map; 91 int r = 0; 92 93 /* Get host physical address for gpa */ 94 hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT); 95 if (is_error_pfn(hpaddr)) { 96 printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); 97 r = -EINVAL; 98 goto out; 99 } 100 hpaddr <<= PAGE_SHIFT; 101 hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK); 102 103 /* and write the mapping ea -> hpa into the pt */ 104 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid); 105 map = find_sid_vsid(vcpu, vsid); 106 if (!map) { 107 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr); 108 WARN_ON(ret < 0); 109 map = find_sid_vsid(vcpu, vsid); 110 } 111 if (!map) { 112 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n", 113 vsid, orig_pte->eaddr); 114 WARN_ON(true); 115 r = -EINVAL; 116 goto out; 117 } 118 119 vsid = map->host_vsid; 120 va = hpt_va(orig_pte->eaddr, vsid, MMU_SEGSIZE_256M); 121 122 if (!orig_pte->may_write) 123 rflags |= HPTE_R_PP; 124 else 125 mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT); 126 127 if (!orig_pte->may_execute) 128 rflags |= HPTE_R_N; 129 else 130 kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT); 131 132 hash = hpt_hash(va, PTE_SIZE, MMU_SEGSIZE_256M); 133 134 map_again: 135 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 136 137 /* In case we tried normal mapping already, let's nuke old entries */ 138 if (attempt > 1) 139 if (ppc_md.hpte_remove(hpteg) < 0) { 140 r = -1; 141 goto out; 142 } 143 144 ret = ppc_md.hpte_insert(hpteg, va, hpaddr, rflags, vflags, MMU_PAGE_4K, MMU_SEGSIZE_256M); 145 146 if (ret < 0) { 147 /* If we couldn't map a primary PTE, try a secondary */ 148 hash = ~hash; 149 vflags ^= HPTE_V_SECONDARY; 150 attempt++; 151 goto map_again; 152 } else { 153 struct hpte_cache *pte = kvmppc_mmu_hpte_cache_next(vcpu); 154 155 trace_kvm_book3s_64_mmu_map(rflags, hpteg, va, hpaddr, orig_pte); 156 157 /* The ppc_md code may give us a secondary entry even though we 158 asked for a primary. Fix up. */ 159 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) { 160 hash = ~hash; 161 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 162 } 163 164 pte->slot = hpteg + (ret & 7); 165 pte->host_va = va; 166 pte->pte = *orig_pte; 167 pte->pfn = hpaddr >> PAGE_SHIFT; 168 169 kvmppc_mmu_hpte_cache_map(vcpu, pte); 170 } 171 172 out: 173 return r; 174 } 175 176 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) 177 { 178 struct kvmppc_sid_map *map; 179 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); 180 u16 sid_map_mask; 181 static int backwards_map = 0; 182 183 if (vcpu->arch.shared->msr & MSR_PR) 184 gvsid |= VSID_PR; 185 186 /* We might get collisions that trap in preceding order, so let's 187 map them differently */ 188 189 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 190 if (backwards_map) 191 sid_map_mask = SID_MAP_MASK - sid_map_mask; 192 193 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 194 195 /* Make sure we're taking the other map next time */ 196 backwards_map = !backwards_map; 197 198 /* Uh-oh ... out of mappings. Let's flush! */ 199 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) { 200 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first; 201 memset(vcpu_book3s->sid_map, 0, 202 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM); 203 kvmppc_mmu_pte_flush(vcpu, 0, 0); 204 kvmppc_mmu_flush_segments(vcpu); 205 } 206 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M); 207 208 map->guest_vsid = gvsid; 209 map->valid = true; 210 211 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid); 212 213 return map; 214 } 215 216 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) 217 { 218 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 219 int i; 220 int max_slb_size = 64; 221 int found_inval = -1; 222 int r; 223 224 if (!svcpu->slb_max) 225 svcpu->slb_max = 1; 226 227 /* Are we overwriting? */ 228 for (i = 1; i < svcpu->slb_max; i++) { 229 if (!(svcpu->slb[i].esid & SLB_ESID_V)) 230 found_inval = i; 231 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) { 232 r = i; 233 goto out; 234 } 235 } 236 237 /* Found a spare entry that was invalidated before */ 238 if (found_inval > 0) { 239 r = found_inval; 240 goto out; 241 } 242 243 /* No spare invalid entry, so create one */ 244 245 if (mmu_slb_size < 64) 246 max_slb_size = mmu_slb_size; 247 248 /* Overflowing -> purge */ 249 if ((svcpu->slb_max) == max_slb_size) 250 kvmppc_mmu_flush_segments(vcpu); 251 252 r = svcpu->slb_max; 253 svcpu->slb_max++; 254 255 out: 256 svcpu_put(svcpu); 257 return r; 258 } 259 260 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) 261 { 262 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 263 u64 esid = eaddr >> SID_SHIFT; 264 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V; 265 u64 slb_vsid = SLB_VSID_USER; 266 u64 gvsid; 267 int slb_index; 268 struct kvmppc_sid_map *map; 269 int r = 0; 270 271 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); 272 273 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { 274 /* Invalidate an entry */ 275 svcpu->slb[slb_index].esid = 0; 276 r = -ENOENT; 277 goto out; 278 } 279 280 map = find_sid_vsid(vcpu, gvsid); 281 if (!map) 282 map = create_sid_map(vcpu, gvsid); 283 284 map->guest_esid = esid; 285 286 slb_vsid |= (map->host_vsid << 12); 287 slb_vsid &= ~SLB_VSID_KP; 288 slb_esid |= slb_index; 289 290 svcpu->slb[slb_index].esid = slb_esid; 291 svcpu->slb[slb_index].vsid = slb_vsid; 292 293 trace_kvm_book3s_slbmte(slb_vsid, slb_esid); 294 295 out: 296 svcpu_put(svcpu); 297 return r; 298 } 299 300 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) 301 { 302 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 303 svcpu->slb_max = 1; 304 svcpu->slb[0].esid = 0; 305 svcpu_put(svcpu); 306 } 307 308 void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu) 309 { 310 kvmppc_mmu_hpte_destroy(vcpu); 311 __destroy_context(to_book3s(vcpu)->context_id[0]); 312 } 313 314 int kvmppc_mmu_init(struct kvm_vcpu *vcpu) 315 { 316 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu); 317 int err; 318 319 err = __init_new_context(); 320 if (err < 0) 321 return -1; 322 vcpu3s->context_id[0] = err; 323 324 vcpu3s->proto_vsid_max = ((vcpu3s->context_id[0] + 1) 325 << USER_ESID_BITS) - 1; 326 vcpu3s->proto_vsid_first = vcpu3s->context_id[0] << USER_ESID_BITS; 327 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first; 328 329 kvmppc_mmu_hpte_init(vcpu); 330 331 return 0; 332 } 333