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