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/book3s/32/mmu-hash.h>
  26 #include <asm/machdep.h>
  27 #include <asm/mmu_context.h>
  28 #include <asm/hw_irq.h>
  29 #include "book3s.h"
  30
  31 /* #define DEBUG_MMU */
  32 /* #define DEBUG_SR */
  33
  34 #ifdef DEBUG_MMU
  35 #define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__)
  36 #else
  37 #define dprintk_mmu(a, ...) do { } while(0)
  38 #endif
  39
  40 #ifdef DEBUG_SR
  41 #define dprintk_sr(a, ...) printk(KERN_INFO a, __VA_ARGS__)
  42 #else
  43 #define dprintk_sr(a, ...) do { } while(0)
  44 #endif
  45
  46 #if PAGE_SHIFT != 12
  47 #error Unknown page size
  48 #endif
  49
  50 #ifdef CONFIG_SMP
  51 #error XXX need to grab mmu_hash_lock
  52 #endif
  53
  54 #ifdef CONFIG_PTE_64BIT
  55 #error Only 32 bit pages are supported for now
  56 #endif
  57
  58 static ulong htab;
  59 static u32 htabmask;
  60
  61 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
  62 {
  63         volatile u32 *pteg;
  64
  65         /* Remove from host HTAB */
  66         pteg = (u32*)pte->slot;
  67         pteg[0] = 0;
  68
  69         /* And make sure it's gone from the TLB too */
  70         asm volatile ("sync");
  71         asm volatile ("tlbie %0" : : "r" (pte->pte.eaddr) : "memory");
  72         asm volatile ("sync");
  73         asm volatile ("tlbsync");
  74 }
  75
  76 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
  77  * a hash, so we don't waste cycles on looping */
  78 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
  79 {
  80         return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
  81                      ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
  82                      ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
  83                      ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
  84                      ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
  85                      ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
  86                      ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
  87                      ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
  88 }
  89
  90
  91 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
  92 {
  93         struct kvmppc_sid_map *map;
  94         u16 sid_map_mask;
  95
  96         if (kvmppc_get_msr(vcpu) & MSR_PR)
  97                 gvsid |= VSID_PR;
  98
  99         sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
 100         map = &to_book3s(vcpu)->sid_map[sid_map_mask];
 101         if (map->guest_vsid == gvsid) {
 102                 dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 103                             gvsid, map->host_vsid);
 104                 return map;
 105         }
 106
 107         map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
 108         if (map->guest_vsid == gvsid) {
 109                 dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 110                             gvsid, map->host_vsid);
 111                 return map;
 112         }
 113
 114         dprintk_sr("SR: Searching 0x%llx -> not found\n", gvsid);
 115         return NULL;
 116 }
 117
 118 static u32 *kvmppc_mmu_get_pteg(struct kvm_vcpu *vcpu, u32 vsid, u32 eaddr,
 119                                 bool primary)
 120 {
 121         u32 page, hash;
 122         ulong pteg = htab;
 123
 124         page = (eaddr & ~ESID_MASK) >> 12;
 125
 126         hash = ((vsid ^ page) << 6);
 127         if (!primary)
 128                 hash = ~hash;
 129
 130         hash &= htabmask;
 131
 132         pteg |= hash;
 133
 134         dprintk_mmu("htab: %lx | hash: %x | htabmask: %x | pteg: %lx\n",
 135                 htab, hash, htabmask, pteg);
 136
 137         return (u32*)pteg;
 138 }
 139
 140 extern char etext[];
 141
 142 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
 143                         bool iswrite)
 144 {
 145         kvm_pfn_t hpaddr;
 146         u64 vpn;
 147         u64 vsid;
 148         struct kvmppc_sid_map *map;
 149         volatile u32 *pteg;
 150         u32 eaddr = orig_pte->eaddr;
 151         u32 pteg0, pteg1;
 152         register int rr = 0;
 153         bool primary = false;
 154         bool evict = false;
 155         struct hpte_cache *pte;
 156         int r = 0;
 157         bool writable;
 158
 159         /* Get host physical address for gpa */
 160         hpaddr = kvmppc_gpa_to_pfn(vcpu, orig_pte->raddr, iswrite, &writable);
 161         if (is_error_noslot_pfn(hpaddr)) {
 162                 printk(KERN_INFO "Couldn't get guest page for gpa %lx!\n",
 163                                  orig_pte->raddr);
 164                 r = -EINVAL;
 165                 goto out;
 166         }
 167         hpaddr <<= PAGE_SHIFT;
 168
 169         /* and write the mapping ea -> hpa into the pt */
 170         vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
 171         map = find_sid_vsid(vcpu, vsid);
 172         if (!map) {
 173                 kvmppc_mmu_map_segment(vcpu, eaddr);
 174                 map = find_sid_vsid(vcpu, vsid);
 175         }
 176         BUG_ON(!map);
 177
 178         vsid = map->host_vsid;
 179         vpn = (vsid << (SID_SHIFT - VPN_SHIFT)) |
 180                 ((eaddr & ~ESID_MASK) >> VPN_SHIFT);
 181 next_pteg:
 182         if (rr == 16) {
 183                 primary = !primary;
 184                 evict = true;
 185                 rr = 0;
 186         }
 187
 188         pteg = kvmppc_mmu_get_pteg(vcpu, vsid, eaddr, primary);
 189
 190         /* not evicting yet */
 191         if (!evict && (pteg[rr] & PTE_V)) {
 192                 rr += 2;
 193                 goto next_pteg;
 194         }
 195
 196         dprintk_mmu("KVM: old PTEG: %p (%d)\n", pteg, rr);
 197         dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 198         dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 199         dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 200         dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 201         dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 202         dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 203         dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 204         dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);
 205
 206         pteg0 = ((eaddr & 0x0fffffff) >> 22) | (vsid << 7) | PTE_V |
 207                 (primary ? 0 : PTE_SEC);
 208         pteg1 = hpaddr | PTE_M | PTE_R | PTE_C;
 209
 210         if (orig_pte->may_write && writable) {
 211                 pteg1 |= PP_RWRW;
 212                 mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
 213         } else {
 214                 pteg1 |= PP_RWRX;
 215         }
 216
 217         if (orig_pte->may_execute)
 218                 kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);
 219
 220         local_irq_disable();
 221
 222         if (pteg[rr]) {
 223                 pteg[rr] = 0;
 224                 asm volatile ("sync");
 225         }
 226         pteg[rr + 1] = pteg1;
 227         pteg[rr] = pteg0;
 228         asm volatile ("sync");
 229
 230         local_irq_enable();
 231
 232         dprintk_mmu("KVM: new PTEG: %p\n", pteg);
 233         dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 234         dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 235         dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 236         dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 237         dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 238         dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 239         dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 240         dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);
 241
 242
 243         /* Now tell our Shadow PTE code about the new page */
 244
 245         pte = kvmppc_mmu_hpte_cache_next(vcpu);
 246         if (!pte) {
 247                 kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 248                 r = -EAGAIN;
 249                 goto out;
 250         }
 251
 252         dprintk_mmu("KVM: %c%c Map 0x%llx: [%lx] 0x%llx (0x%llx) -> %lx\n",
 253                     orig_pte->may_write ? 'w' : '-',
 254                     orig_pte->may_execute ? 'x' : '-',
 255                     orig_pte->eaddr, (ulong)pteg, vpn,
 256                     orig_pte->vpage, hpaddr);
 257
 258         pte->slot = (ulong)&pteg[rr];
 259         pte->host_vpn = vpn;
 260         pte->pte = *orig_pte;
 261         pte->pfn = hpaddr >> PAGE_SHIFT;
 262
 263         kvmppc_mmu_hpte_cache_map(vcpu, pte);
 264
 265         kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 266 out:
 267         return r;
 268 }
 269
 270 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
 271 {
 272         kvmppc_mmu_pte_vflush(vcpu, pte->vpage, 0xfffffffffULL);
 273 }
 274
 275 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
 276 {
 277         struct kvmppc_sid_map *map;
 278         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 279         u16 sid_map_mask;
 280         static int backwards_map = 0;
 281
 282         if (kvmppc_get_msr(vcpu) & MSR_PR)
 283                 gvsid |= VSID_PR;
 284
 285         /* We might get collisions that trap in preceding order, so let's
 286            map them differently */
 287
 288         sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
 289         if (backwards_map)
 290                 sid_map_mask = SID_MAP_MASK - sid_map_mask;
 291
 292         map = &to_book3s(vcpu)->sid_map[sid_map_mask];
 293
 294         /* Make sure we're taking the other map next time */
 295         backwards_map = !backwards_map;
 296
 297         /* Uh-oh ... out of mappings. Let's flush! */
 298         if (vcpu_book3s->vsid_next >= VSID_POOL_SIZE) {
 299                 vcpu_book3s->vsid_next = 0;
 300                 memset(vcpu_book3s->sid_map, 0,
 301                        sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
 302                 kvmppc_mmu_pte_flush(vcpu, 0, 0);
 303                 kvmppc_mmu_flush_segments(vcpu);
 304         }
 305         map->host_vsid = vcpu_book3s->vsid_pool[vcpu_book3s->vsid_next];
 306         vcpu_book3s->vsid_next++;
 307
 308         map->guest_vsid = gvsid;
 309         map->valid = true;
 310
 311         return map;
 312 }
 313
 314 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
 315 {
 316         u32 esid = eaddr >> SID_SHIFT;
 317         u64 gvsid;
 318         u32 sr;
 319         struct kvmppc_sid_map *map;
 320         struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
 321         int r = 0;
 322
 323         if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
 324                 /* Invalidate an entry */
 325                 svcpu->sr[esid] = SR_INVALID;
 326                 r = -ENOENT;
 327                 goto out;
 328         }
 329
 330         map = find_sid_vsid(vcpu, gvsid);
 331         if (!map)
 332                 map = create_sid_map(vcpu, gvsid);
 333
 334         map->guest_esid = esid;
 335         sr = map->host_vsid | SR_KP;
 336         svcpu->sr[esid] = sr;
 337
 338         dprintk_sr("MMU: mtsr %d, 0x%x\n", esid, sr);
 339
 340 out:
 341         svcpu_put(svcpu);
 342         return r;
 343 }
 344
 345 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
 346 {
 347         int i;
 348         struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
 349
 350         dprintk_sr("MMU: flushing all segments (%d)\n", ARRAY_SIZE(svcpu->sr));
 351         for (i = 0; i < ARRAY_SIZE(svcpu->sr); i++)
 352                 svcpu->sr[i] = SR_INVALID;
 353
 354         svcpu_put(svcpu);
 355 }
 356
 357 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
 358 {
 359         int i;
 360
 361         kvmppc_mmu_hpte_destroy(vcpu);
 362         preempt_disable();
 363         for (i = 0; i < SID_CONTEXTS; i++)
 364                 __destroy_context(to_book3s(vcpu)->context_id[i]);
 365         preempt_enable();
 366 }
 367
 368 /* From mm/mmu_context_hash32.c */
 369 #define CTX_TO_VSID(c, id)      ((((c) * (897 * 16)) + (id * 0x111)) & 0xffffff)
 370
 371 int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
 372 {
 373         struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
 374         int err;
 375         ulong sdr1;
 376         int i;
 377         int j;
 378
 379         for (i = 0; i < SID_CONTEXTS; i++) {
 380                 err = __init_new_context();
 381                 if (err < 0)
 382                         goto init_fail;
 383                 vcpu3s->context_id[i] = err;
 384
 385                 /* Remember context id for this combination */
 386                 for (j = 0; j < 16; j++)
 387                         vcpu3s->vsid_pool[(i * 16) + j] = CTX_TO_VSID(err, j);
 388         }
 389
 390         vcpu3s->vsid_next = 0;
 391
 392         /* Remember where the HTAB is */
 393         asm ( "mfsdr1 %0" : "=r"(sdr1) );
 394         htabmask = ((sdr1 & 0x1FF) << 16) | 0xFFC0;
 395         htab = (ulong)__va(sdr1 & 0xffff0000);
 396
 397         kvmppc_mmu_hpte_init(vcpu);
 398
 399         return 0;
 400
 401 init_fail:
 402         for (j = 0; j < i; j++) {
 403                 if (!vcpu3s->context_id[j])
 404                         continue;
 405
 406                 __destroy_context(to_book3s(vcpu)->context_id[j]);
 407         }
 408
 409         return -1;
 410 }