arch/powerpc/kvm/book3s_32_mmu_host.c

   1 /*
   2  * Copyright (C) 2010 SUSE Linux Products GmbH. All rights reserved.
   3  *
   4  * Authors:
   5  *     Alexander Graf <agraf@suse.de>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License, version 2, as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  */
  20
  21 #include <linux/kvm_host.h>
  22
  23 #include <asm/kvm_ppc.h>
  24 #include <asm/kvm_book3s.h>
  25 #include <asm/mmu-hash32.h>
  26 #include <asm/machdep.h>
  27 #include <asm/mmu_context.h>
  28 #include <asm/hw_irq.h>
  29
  30 /* #define DEBUG_MMU */
  31 /* #define DEBUG_SR */
  32
  33 #ifdef DEBUG_MMU
  34 #define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__)
  35 #else
  36 #define dprintk_mmu(a, ...) do { } while(0)
  37 #endif
  38
  39 #ifdef DEBUG_SR
  40 #define dprintk_sr(a, ...) printk(KERN_INFO a, __VA_ARGS__)
  41 #else
  42 #define dprintk_sr(a, ...) do { } while(0)
  43 #endif
  44
  45 #if PAGE_SHIFT != 12
  46 #error Unknown page size
  47 #endif
  48
  49 #ifdef CONFIG_SMP
  50 #error XXX need to grab mmu_hash_lock
  51 #endif
  52
  53 #ifdef CONFIG_PTE_64BIT
  54 #error Only 32 bit pages are supported for now
  55 #endif
  56
  57 static ulong htab;
  58 static u32 htabmask;
  59
  60 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
  61 {
  62         volatile u32 *pteg;
  63
  64         /* Remove from host HTAB */
  65         pteg = (u32*)pte->slot;
  66         pteg[0] = 0;
  67
  68         /* And make sure it's gone from the TLB too */
  69         asm volatile ("sync");
  70         asm volatile ("tlbie %0" : : "r" (pte->pte.eaddr) : "memory");
  71         asm volatile ("sync");
  72         asm volatile ("tlbsync");
  73 }
  74
  75 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
  76  * a hash, so we don't waste cycles on looping */
  77 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
  78 {
  79         return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
  80                      ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
  81                      ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
  82                      ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
  83                      ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
  84                      ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
  85                      ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
  86                      ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
  87 }
  88
  89
  90 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
  91 {
  92         struct kvmppc_sid_map *map;
  93         u16 sid_map_mask;
  94
  95         if (kvmppc_get_msr(vcpu) & MSR_PR)
  96                 gvsid |= VSID_PR;
  97
  98         sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
  99         map = &to_book3s(vcpu)->sid_map[sid_map_mask];
 100         if (map->guest_vsid == gvsid) {
 101                 dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 102                             gvsid, map->host_vsid);
 103                 return map;
 104         }
 105
 106         map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
 107         if (map->guest_vsid == gvsid) {
 108                 dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 109                             gvsid, map->host_vsid);
 110                 return map;
 111         }
 112
 113         dprintk_sr("SR: Searching 0x%llx -> not found\n", gvsid);
 114         return NULL;
 115 }
 116
 117 static u32 *kvmppc_mmu_get_pteg(struct kvm_vcpu *vcpu, u32 vsid, u32 eaddr,
 118                                 bool primary)
 119 {
 120         u32 page, hash;
 121         ulong pteg = htab;
 122
 123         page = (eaddr & ~ESID_MASK) >> 12;
 124
 125         hash = ((vsid ^ page) << 6);
 126         if (!primary)
 127                 hash = ~hash;
 128
 129         hash &= htabmask;
 130
 131         pteg |= hash;
 132
 133         dprintk_mmu("htab: %lx | hash: %x | htabmask: %x | pteg: %lx\n",
 134                 htab, hash, htabmask, pteg);
 135
 136         return (u32*)pteg;
 137 }
 138
 139 extern char etext[];
 140
 141 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
 142                         bool iswrite)
 143 {
 144         pfn_t hpaddr;
 145         u64 vpn;
 146         u64 vsid;
 147         struct kvmppc_sid_map *map;
 148         volatile u32 *pteg;
 149         u32 eaddr = orig_pte->eaddr;
 150         u32 pteg0, pteg1;
 151         register int rr = 0;
 152         bool primary = false;
 153         bool evict = false;
 154         struct hpte_cache *pte;
 155         int r = 0;
 156         bool writable;
 157
 158         /* Get host physical address for gpa */
 159         hpaddr = kvmppc_gpa_to_pfn(vcpu, orig_pte->raddr, iswrite, &writable);
 160         if (is_error_noslot_pfn(hpaddr)) {
 161                 printk(KERN_INFO "Couldn't get guest page for gpa %lx!\n",
 162                                  orig_pte->raddr);
 163                 r = -EINVAL;
 164                 goto out;
 165         }
 166         hpaddr <<= PAGE_SHIFT;
 167
 168         /* and write the mapping ea -> hpa into the pt */
 169         vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
 170         map = find_sid_vsid(vcpu, vsid);
 171         if (!map) {
 172                 kvmppc_mmu_map_segment(vcpu, eaddr);
 173                 map = find_sid_vsid(vcpu, vsid);
 174         }
 175         BUG_ON(!map);
 176
 177         vsid = map->host_vsid;
 178         vpn = (vsid << (SID_SHIFT - VPN_SHIFT)) |
 179                 ((eaddr & ~ESID_MASK) >> VPN_SHIFT);
 180 next_pteg:
 181         if (rr == 16) {
 182                 primary = !primary;
 183                 evict = true;
 184                 rr = 0;
 185         }
 186
 187         pteg = kvmppc_mmu_get_pteg(vcpu, vsid, eaddr, primary);
 188
 189         /* not evicting yet */
 190         if (!evict && (pteg[rr] & PTE_V)) {
 191                 rr += 2;
 192                 goto next_pteg;
 193         }
 194
 195         dprintk_mmu("KVM: old PTEG: %p (%d)\n", pteg, rr);
 196         dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 197         dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 198         dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 199         dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 200         dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 201         dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 202         dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 203         dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);
 204
 205         pteg0 = ((eaddr & 0x0fffffff) >> 22) | (vsid << 7) | PTE_V |
 206                 (primary ? 0 : PTE_SEC);
 207         pteg1 = hpaddr | PTE_M | PTE_R | PTE_C;
 208
 209         if (orig_pte->may_write && writable) {
 210                 pteg1 |= PP_RWRW;
 211                 mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
 212         } else {
 213                 pteg1 |= PP_RWRX;
 214         }
 215
 216         if (orig_pte->may_execute)
 217                 kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);
 218
 219         local_irq_disable();
 220
 221         if (pteg[rr]) {
 222                 pteg[rr] = 0;
 223                 asm volatile ("sync");
 224         }
 225         pteg[rr + 1] = pteg1;
 226         pteg[rr] = pteg0;
 227         asm volatile ("sync");
 228
 229         local_irq_enable();
 230
 231         dprintk_mmu("KVM: new PTEG: %p\n", pteg);
 232         dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 233         dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 234         dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 235         dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 236         dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 237         dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 238         dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 239         dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);
 240
 241
 242         /* Now tell our Shadow PTE code about the new page */
 243
 244         pte = kvmppc_mmu_hpte_cache_next(vcpu);
 245         if (!pte) {
 246                 kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 247                 r = -EAGAIN;
 248                 goto out;
 249         }
 250
 251         dprintk_mmu("KVM: %c%c Map 0x%llx: [%lx] 0x%llx (0x%llx) -> %lx\n",
 252                     orig_pte->may_write ? 'w' : '-',
 253                     orig_pte->may_execute ? 'x' : '-',
 254                     orig_pte->eaddr, (ulong)pteg, vpn,
 255                     orig_pte->vpage, hpaddr);
 256
 257         pte->slot = (ulong)&pteg[rr];
 258         pte->host_vpn = vpn;
 259         pte->pte = *orig_pte;
 260         pte->pfn = hpaddr >> PAGE_SHIFT;
 261
 262         kvmppc_mmu_hpte_cache_map(vcpu, pte);
 263
 264         kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 265 out:
 266         return r;
 267 }
 268
 269 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
 270 {
 271         kvmppc_mmu_pte_vflush(vcpu, pte->vpage, 0xfffffffffULL);
 272 }
 273
 274 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
 275 {
 276         struct kvmppc_sid_map *map;
 277         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 278         u16 sid_map_mask;
 279         static int backwards_map = 0;
 280
 281         if (kvmppc_get_msr(vcpu) & MSR_PR)
 282                 gvsid |= VSID_PR;
 283
 284         /* We might get collisions that trap in preceding order, so let's
 285            map them differently */
 286
 287         sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
 288         if (backwards_map)
 289                 sid_map_mask = SID_MAP_MASK - sid_map_mask;
 290
 291         map = &to_book3s(vcpu)->sid_map[sid_map_mask];
 292
 293         /* Make sure we're taking the other map next time */
 294         backwards_map = !backwards_map;
 295
 296         /* Uh-oh ... out of mappings. Let's flush! */
 297         if (vcpu_book3s->vsid_next >= VSID_POOL_SIZE) {
 298                 vcpu_book3s->vsid_next = 0;
 299                 memset(vcpu_book3s->sid_map, 0,
 300                        sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
 301                 kvmppc_mmu_pte_flush(vcpu, 0, 0);
 302                 kvmppc_mmu_flush_segments(vcpu);
 303         }
 304         map->host_vsid = vcpu_book3s->vsid_pool[vcpu_book3s->vsid_next];
 305         vcpu_book3s->vsid_next++;
 306
 307         map->guest_vsid = gvsid;
 308         map->valid = true;
 309
 310         return map;
 311 }
 312
 313 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
 314 {
 315         u32 esid = eaddr >> SID_SHIFT;
 316         u64 gvsid;
 317         u32 sr;
 318         struct kvmppc_sid_map *map;
 319         struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
 320         int r = 0;
 321
 322         if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
 323                 /* Invalidate an entry */
 324                 svcpu->sr[esid] = SR_INVALID;
 325                 r = -ENOENT;
 326                 goto out;
 327         }
 328
 329         map = find_sid_vsid(vcpu, gvsid);
 330         if (!map)
 331                 map = create_sid_map(vcpu, gvsid);
 332
 333         map->guest_esid = esid;
 334         sr = map->host_vsid | SR_KP;
 335         svcpu->sr[esid] = sr;
 336
 337         dprintk_sr("MMU: mtsr %d, 0x%x\n", esid, sr);
 338
 339 out:
 340         svcpu_put(svcpu);
 341         return r;
 342 }
 343
 344 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
 345 {
 346         int i;
 347         struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
 348
 349         dprintk_sr("MMU: flushing all segments (%d)\n", ARRAY_SIZE(svcpu->sr));
 350         for (i = 0; i < ARRAY_SIZE(svcpu->sr); i++)
 351                 svcpu->sr[i] = SR_INVALID;
 352
 353         svcpu_put(svcpu);
 354 }
 355
 356 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
 357 {
 358         int i;
 359
 360         kvmppc_mmu_hpte_destroy(vcpu);
 361         preempt_disable();
 362         for (i = 0; i < SID_CONTEXTS; i++)
 363                 __destroy_context(to_book3s(vcpu)->context_id[i]);
 364         preempt_enable();
 365 }
 366
 367 /* From mm/mmu_context_hash32.c */
 368 #define CTX_TO_VSID(c, id)      ((((c) * (897 * 16)) + (id * 0x111)) & 0xffffff)
 369
 370 int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
 371 {
 372         struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
 373         int err;
 374         ulong sdr1;
 375         int i;
 376         int j;
 377
 378         for (i = 0; i < SID_CONTEXTS; i++) {
 379                 err = __init_new_context();
 380                 if (err < 0)
 381                         goto init_fail;
 382                 vcpu3s->context_id[i] = err;
 383
 384                 /* Remember context id for this combination */
 385                 for (j = 0; j < 16; j++)
 386                         vcpu3s->vsid_pool[(i * 16) + j] = CTX_TO_VSID(err, j);
 387         }
 388
 389         vcpu3s->vsid_next = 0;
 390
 391         /* Remember where the HTAB is */
 392         asm ( "mfsdr1 %0" : "=r"(sdr1) );
 393         htabmask = ((sdr1 & 0x1FF) << 16) | 0xFFC0;
 394         htab = (ulong)__va(sdr1 & 0xffff0000);
 395
 396         kvmppc_mmu_hpte_init(vcpu);
 397
 398         return 0;
 399
 400 init_fail:
 401         for (j = 0; j < i; j++) {
 402                 if (!vcpu3s->context_id[j])
 403                         continue;
 404
 405                 __destroy_context(to_book3s(vcpu)->context_id[j]);
 406         }
 407
 408         return -1;
 409 }