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_vpn, 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 unsigned long vpn; 84 pfn_t hpaddr; 85 ulong hash, hpteg; 86 u64 vsid; 87 int ret; 88 int rflags = 0x192; 89 int vflags = 0; 90 int attempt = 0; 91 struct kvmppc_sid_map *map; 92 int r = 0; 93 94 /* Get host physical address for gpa */ 95 hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT); 96 if (is_error_noslot_pfn(hpaddr)) { 97 printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); 98 r = -EINVAL; 99 goto out; 100 } 101 hpaddr <<= PAGE_SHIFT; 102 hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK); 103 104 /* and write the mapping ea -> hpa into the pt */ 105 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid); 106 map = find_sid_vsid(vcpu, vsid); 107 if (!map) { 108 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr); 109 WARN_ON(ret < 0); 110 map = find_sid_vsid(vcpu, vsid); 111 } 112 if (!map) { 113 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n", 114 vsid, orig_pte->eaddr); 115 WARN_ON(true); 116 r = -EINVAL; 117 goto out; 118 } 119 120 vsid = map->host_vsid; 121 vpn = hpt_vpn(orig_pte->eaddr, vsid, MMU_SEGSIZE_256M); 122 123 if (!orig_pte->may_write) 124 rflags |= HPTE_R_PP; 125 else 126 mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT); 127 128 if (!orig_pte->may_execute) 129 rflags |= HPTE_R_N; 130 else 131 kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT); 132 133 hash = hpt_hash(vpn, PTE_SIZE, MMU_SEGSIZE_256M); 134 135 map_again: 136 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 137 138 /* In case we tried normal mapping already, let's nuke old entries */ 139 if (attempt > 1) 140 if (ppc_md.hpte_remove(hpteg) < 0) { 141 r = -1; 142 goto out; 143 } 144 145 ret = ppc_md.hpte_insert(hpteg, vpn, hpaddr, rflags, vflags, 146 MMU_PAGE_4K, MMU_SEGSIZE_256M); 147 148 if (ret < 0) { 149 /* If we couldn't map a primary PTE, try a secondary */ 150 hash = ~hash; 151 vflags ^= HPTE_V_SECONDARY; 152 attempt++; 153 goto map_again; 154 } else { 155 struct hpte_cache *pte = kvmppc_mmu_hpte_cache_next(vcpu); 156 157 trace_kvm_book3s_64_mmu_map(rflags, hpteg, 158 vpn, hpaddr, orig_pte); 159 160 /* The ppc_md code may give us a secondary entry even though we 161 asked for a primary. Fix up. */ 162 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) { 163 hash = ~hash; 164 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 165 } 166 167 pte->slot = hpteg + (ret & 7); 168 pte->host_vpn = vpn; 169 pte->pte = *orig_pte; 170 pte->pfn = hpaddr >> PAGE_SHIFT; 171 172 kvmppc_mmu_hpte_cache_map(vcpu, pte); 173 } 174 kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT); 175 176 out: 177 return r; 178 } 179 180 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) 181 { 182 struct kvmppc_sid_map *map; 183 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); 184 u16 sid_map_mask; 185 static int backwards_map = 0; 186 187 if (vcpu->arch.shared->msr & MSR_PR) 188 gvsid |= VSID_PR; 189 190 /* We might get collisions that trap in preceding order, so let's 191 map them differently */ 192 193 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 194 if (backwards_map) 195 sid_map_mask = SID_MAP_MASK - sid_map_mask; 196 197 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 198 199 /* Make sure we're taking the other map next time */ 200 backwards_map = !backwards_map; 201 202 /* Uh-oh ... out of mappings. Let's flush! */ 203 if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) { 204 vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first; 205 memset(vcpu_book3s->sid_map, 0, 206 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM); 207 kvmppc_mmu_pte_flush(vcpu, 0, 0); 208 kvmppc_mmu_flush_segments(vcpu); 209 } 210 map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M); 211 212 map->guest_vsid = gvsid; 213 map->valid = true; 214 215 trace_kvm_book3s_slb_map(sid_map_mask, gvsid, map->host_vsid); 216 217 return map; 218 } 219 220 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) 221 { 222 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 223 int i; 224 int max_slb_size = 64; 225 int found_inval = -1; 226 int r; 227 228 if (!svcpu->slb_max) 229 svcpu->slb_max = 1; 230 231 /* Are we overwriting? */ 232 for (i = 1; i < svcpu->slb_max; i++) { 233 if (!(svcpu->slb[i].esid & SLB_ESID_V)) 234 found_inval = i; 235 else if ((svcpu->slb[i].esid & ESID_MASK) == esid) { 236 r = i; 237 goto out; 238 } 239 } 240 241 /* Found a spare entry that was invalidated before */ 242 if (found_inval > 0) { 243 r = found_inval; 244 goto out; 245 } 246 247 /* No spare invalid entry, so create one */ 248 249 if (mmu_slb_size < 64) 250 max_slb_size = mmu_slb_size; 251 252 /* Overflowing -> purge */ 253 if ((svcpu->slb_max) == max_slb_size) 254 kvmppc_mmu_flush_segments(vcpu); 255 256 r = svcpu->slb_max; 257 svcpu->slb_max++; 258 259 out: 260 svcpu_put(svcpu); 261 return r; 262 } 263 264 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) 265 { 266 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 267 u64 esid = eaddr >> SID_SHIFT; 268 u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V; 269 u64 slb_vsid = SLB_VSID_USER; 270 u64 gvsid; 271 int slb_index; 272 struct kvmppc_sid_map *map; 273 int r = 0; 274 275 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); 276 277 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { 278 /* Invalidate an entry */ 279 svcpu->slb[slb_index].esid = 0; 280 r = -ENOENT; 281 goto out; 282 } 283 284 map = find_sid_vsid(vcpu, gvsid); 285 if (!map) 286 map = create_sid_map(vcpu, gvsid); 287 288 map->guest_esid = esid; 289 290 slb_vsid |= (map->host_vsid << 12); 291 slb_vsid &= ~SLB_VSID_KP; 292 slb_esid |= slb_index; 293 294 svcpu->slb[slb_index].esid = slb_esid; 295 svcpu->slb[slb_index].vsid = slb_vsid; 296 297 trace_kvm_book3s_slbmte(slb_vsid, slb_esid); 298 299 out: 300 svcpu_put(svcpu); 301 return r; 302 } 303 304 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) 305 { 306 struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); 307 svcpu->slb_max = 1; 308 svcpu->slb[0].esid = 0; 309 svcpu_put(svcpu); 310 } 311 312 void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu) 313 { 314 kvmppc_mmu_hpte_destroy(vcpu); 315 __destroy_context(to_book3s(vcpu)->context_id[0]); 316 } 317 318 int kvmppc_mmu_init(struct kvm_vcpu *vcpu) 319 { 320 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu); 321 int err; 322 323 err = __init_new_context(); 324 if (err < 0) 325 return -1; 326 vcpu3s->context_id[0] = err; 327 328 vcpu3s->proto_vsid_max = ((vcpu3s->context_id[0] + 1) 329 << USER_ESID_BITS) - 1; 330 vcpu3s->proto_vsid_first = vcpu3s->context_id[0] << USER_ESID_BITS; 331 vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first; 332 333 kvmppc_mmu_hpte_init(vcpu); 334 335 return 0; 336 } 337