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 #include <linux/hash.h> 24 25 #include <asm/kvm_ppc.h> 26 #include <asm/kvm_book3s.h> 27 #include <asm/mmu-hash64.h> 28 #include <asm/machdep.h> 29 #include <asm/mmu_context.h> 30 #include <asm/hw_irq.h> 31 32 #define PTE_SIZE 12 33 #define VSID_ALL 0 34 35 /* #define DEBUG_MMU */ 36 /* #define DEBUG_SLB */ 37 38 #ifdef DEBUG_MMU 39 #define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__) 40 #else 41 #define dprintk_mmu(a, ...) do { } while(0) 42 #endif 43 44 #ifdef DEBUG_SLB 45 #define dprintk_slb(a, ...) printk(KERN_INFO a, __VA_ARGS__) 46 #else 47 #define dprintk_slb(a, ...) do { } while(0) 48 #endif 49 50 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte) 51 { 52 ppc_md.hpte_invalidate(pte->slot, pte->host_va, 53 MMU_PAGE_4K, MMU_SEGSIZE_256M, 54 false); 55 } 56 57 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using 58 * a hash, so we don't waste cycles on looping */ 59 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid) 60 { 61 return hash_64(gvsid, SID_MAP_BITS); 62 } 63 64 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid) 65 { 66 struct kvmppc_sid_map *map; 67 u16 sid_map_mask; 68 69 if (vcpu->arch.msr & MSR_PR) 70 gvsid |= VSID_PR; 71 72 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 73 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 74 if (map->guest_vsid == gvsid) { 75 dprintk_slb("SLB: Searching: 0x%llx -> 0x%llx\n", 76 gvsid, map->host_vsid); 77 return map; 78 } 79 80 map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask]; 81 if (map->guest_vsid == gvsid) { 82 dprintk_slb("SLB: Searching 0x%llx -> 0x%llx\n", 83 gvsid, map->host_vsid); 84 return map; 85 } 86 87 dprintk_slb("SLB: Searching %d/%d: 0x%llx -> not found\n", 88 sid_map_mask, SID_MAP_MASK - sid_map_mask, gvsid); 89 return NULL; 90 } 91 92 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte) 93 { 94 pfn_t hpaddr; 95 ulong hash, hpteg, va; 96 u64 vsid; 97 int ret; 98 int rflags = 0x192; 99 int vflags = 0; 100 int attempt = 0; 101 struct kvmppc_sid_map *map; 102 103 /* Get host physical address for gpa */ 104 hpaddr = gfn_to_pfn(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT); 105 if (kvm_is_error_hva(hpaddr)) { 106 printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); 107 return -EINVAL; 108 } 109 hpaddr <<= PAGE_SHIFT; 110 #if PAGE_SHIFT == 12 111 #elif PAGE_SHIFT == 16 112 hpaddr |= orig_pte->raddr & 0xf000; 113 #else 114 #error Unknown page size 115 #endif 116 117 /* and write the mapping ea -> hpa into the pt */ 118 vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid); 119 map = find_sid_vsid(vcpu, vsid); 120 if (!map) { 121 ret = kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr); 122 WARN_ON(ret < 0); 123 map = find_sid_vsid(vcpu, vsid); 124 } 125 if (!map) { 126 printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n", 127 vsid, orig_pte->eaddr); 128 WARN_ON(true); 129 return -EINVAL; 130 } 131 132 vsid = map->host_vsid; 133 va = hpt_va(orig_pte->eaddr, vsid, MMU_SEGSIZE_256M); 134 135 if (!orig_pte->may_write) 136 rflags |= HPTE_R_PP; 137 else 138 mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT); 139 140 if (!orig_pte->may_execute) 141 rflags |= HPTE_R_N; 142 143 hash = hpt_hash(va, PTE_SIZE, MMU_SEGSIZE_256M); 144 145 map_again: 146 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 147 148 /* In case we tried normal mapping already, let's nuke old entries */ 149 if (attempt > 1) 150 if (ppc_md.hpte_remove(hpteg) < 0) 151 return -1; 152 153 ret = ppc_md.hpte_insert(hpteg, va, hpaddr, rflags, vflags, MMU_PAGE_4K, MMU_SEGSIZE_256M); 154 155 if (ret < 0) { 156 /* If we couldn't map a primary PTE, try a secondary */ 157 hash = ~hash; 158 vflags ^= HPTE_V_SECONDARY; 159 attempt++; 160 goto map_again; 161 } else { 162 struct hpte_cache *pte = kvmppc_mmu_hpte_cache_next(vcpu); 163 164 dprintk_mmu("KVM: %c%c Map 0x%lx: [%lx] 0x%lx (0x%llx) -> %lx\n", 165 ((rflags & HPTE_R_PP) == 3) ? '-' : 'w', 166 (rflags & HPTE_R_N) ? '-' : 'x', 167 orig_pte->eaddr, hpteg, va, orig_pte->vpage, hpaddr); 168 169 /* The ppc_md code may give us a secondary entry even though we 170 asked for a primary. Fix up. */ 171 if ((ret & _PTEIDX_SECONDARY) && !(vflags & HPTE_V_SECONDARY)) { 172 hash = ~hash; 173 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); 174 } 175 176 pte->slot = hpteg + (ret & 7); 177 pte->host_va = va; 178 pte->pte = *orig_pte; 179 pte->pfn = hpaddr >> PAGE_SHIFT; 180 181 kvmppc_mmu_hpte_cache_map(vcpu, pte); 182 } 183 184 return 0; 185 } 186 187 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) 188 { 189 struct kvmppc_sid_map *map; 190 struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); 191 u16 sid_map_mask; 192 static int backwards_map = 0; 193 194 if (vcpu->arch.msr & MSR_PR) 195 gvsid |= VSID_PR; 196 197 /* We might get collisions that trap in preceding order, so let's 198 map them differently */ 199 200 sid_map_mask = kvmppc_sid_hash(vcpu, gvsid); 201 if (backwards_map) 202 sid_map_mask = SID_MAP_MASK - sid_map_mask; 203 204 map = &to_book3s(vcpu)->sid_map[sid_map_mask]; 205 206 /* Make sure we're taking the other map next time */ 207 backwards_map = !backwards_map; 208 209 /* Uh-oh ... out of mappings. Let's flush! */ 210 if (vcpu_book3s->vsid_next == vcpu_book3s->vsid_max) { 211 vcpu_book3s->vsid_next = vcpu_book3s->vsid_first; 212 memset(vcpu_book3s->sid_map, 0, 213 sizeof(struct kvmppc_sid_map) * SID_MAP_NUM); 214 kvmppc_mmu_pte_flush(vcpu, 0, 0); 215 kvmppc_mmu_flush_segments(vcpu); 216 } 217 map->host_vsid = vcpu_book3s->vsid_next++; 218 219 map->guest_vsid = gvsid; 220 map->valid = true; 221 222 dprintk_slb("SLB: New mapping at %d: 0x%llx -> 0x%llx\n", 223 sid_map_mask, gvsid, map->host_vsid); 224 225 return map; 226 } 227 228 static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) 229 { 230 int i; 231 int max_slb_size = 64; 232 int found_inval = -1; 233 int r; 234 235 if (!to_svcpu(vcpu)->slb_max) 236 to_svcpu(vcpu)->slb_max = 1; 237 238 /* Are we overwriting? */ 239 for (i = 1; i < to_svcpu(vcpu)->slb_max; i++) { 240 if (!(to_svcpu(vcpu)->slb[i].esid & SLB_ESID_V)) 241 found_inval = i; 242 else if ((to_svcpu(vcpu)->slb[i].esid & ESID_MASK) == esid) 243 return i; 244 } 245 246 /* Found a spare entry that was invalidated before */ 247 if (found_inval > 0) 248 return found_inval; 249 250 /* No spare invalid entry, so create one */ 251 252 if (mmu_slb_size < 64) 253 max_slb_size = mmu_slb_size; 254 255 /* Overflowing -> purge */ 256 if ((to_svcpu(vcpu)->slb_max) == max_slb_size) 257 kvmppc_mmu_flush_segments(vcpu); 258 259 r = to_svcpu(vcpu)->slb_max; 260 to_svcpu(vcpu)->slb_max++; 261 262 return r; 263 } 264 265 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) 266 { 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; 273 274 slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); 275 276 if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { 277 /* Invalidate an entry */ 278 to_svcpu(vcpu)->slb[slb_index].esid = 0; 279 return -ENOENT; 280 } 281 282 map = find_sid_vsid(vcpu, gvsid); 283 if (!map) 284 map = create_sid_map(vcpu, gvsid); 285 286 map->guest_esid = esid; 287 288 slb_vsid |= (map->host_vsid << 12); 289 slb_vsid &= ~SLB_VSID_KP; 290 slb_esid |= slb_index; 291 292 to_svcpu(vcpu)->slb[slb_index].esid = slb_esid; 293 to_svcpu(vcpu)->slb[slb_index].vsid = slb_vsid; 294 295 dprintk_slb("slbmte %#llx, %#llx\n", slb_vsid, slb_esid); 296 297 return 0; 298 } 299 300 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) 301 { 302 to_svcpu(vcpu)->slb_max = 1; 303 to_svcpu(vcpu)->slb[0].esid = 0; 304 } 305 306 void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu) 307 { 308 kvmppc_mmu_hpte_destroy(vcpu); 309 __destroy_context(to_book3s(vcpu)->context_id); 310 } 311 312 int kvmppc_mmu_init(struct kvm_vcpu *vcpu) 313 { 314 struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu); 315 int err; 316 317 err = __init_new_context(); 318 if (err < 0) 319 return -1; 320 vcpu3s->context_id = err; 321 322 vcpu3s->vsid_max = ((vcpu3s->context_id + 1) << USER_ESID_BITS) - 1; 323 vcpu3s->vsid_first = vcpu3s->context_id << USER_ESID_BITS; 324 vcpu3s->vsid_next = vcpu3s->vsid_first; 325 326 kvmppc_mmu_hpte_init(vcpu); 327 328 return 0; 329 } 330