arch/powerpc/kvm/book3s_32_mmu.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2, as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software
  13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  14  *
  15  * Copyright SUSE Linux Products GmbH 2009
  16  *
  17  * Authors: Alexander Graf <agraf@suse.de>
  18  */
  19
  20 #include <linux/types.h>
  21 #include <linux/string.h>
  22 #include <linux/kvm.h>
  23 #include <linux/kvm_host.h>
  24 #include <linux/highmem.h>
  25
  26 #include <asm/tlbflush.h>
  27 #include <asm/kvm_ppc.h>
  28 #include <asm/kvm_book3s.h>
  29
  30 /* #define DEBUG_MMU */
  31 /* #define DEBUG_MMU_PTE */
  32 /* #define DEBUG_MMU_PTE_IP 0xfff14c40 */
  33
  34 #ifdef DEBUG_MMU
  35 #define dprintk(X...) printk(KERN_INFO X)
  36 #else
  37 #define dprintk(X...) do { } while(0)
  38 #endif
  39
  40 #ifdef DEBUG_MMU_PTE
  41 #define dprintk_pte(X...) printk(KERN_INFO X)
  42 #else
  43 #define dprintk_pte(X...) do { } while(0)
  44 #endif
  45
  46 #define PTEG_FLAG_ACCESSED      0x00000100
  47 #define PTEG_FLAG_DIRTY         0x00000080
  48 #ifndef SID_SHIFT
  49 #define SID_SHIFT               28
  50 #endif
  51
  52 static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
  53 {
  54 #ifdef DEBUG_MMU_PTE_IP
  55         return vcpu->arch.pc == DEBUG_MMU_PTE_IP;
  56 #else
  57         return true;
  58 #endif
  59 }
  60
  61 static inline u32 sr_vsid(u32 sr_raw)
  62 {
  63         return sr_raw & 0x0fffffff;
  64 }
  65
  66 static inline bool sr_valid(u32 sr_raw)
  67 {
  68         return (sr_raw & 0x80000000) ? false : true;
  69 }
  70
  71 static inline bool sr_ks(u32 sr_raw)
  72 {
  73         return (sr_raw & 0x40000000) ? true: false;
  74 }
  75
  76 static inline bool sr_kp(u32 sr_raw)
  77 {
  78         return (sr_raw & 0x20000000) ? true: false;
  79 }
  80
  81 static inline bool sr_nx(u32 sr_raw)
  82 {
  83         return (sr_raw & 0x10000000) ? true: false;
  84 }
  85
  86 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  87                                           struct kvmppc_pte *pte, bool data,
  88                                           bool iswrite);
  89 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  90                                              u64 *vsid);
  91
  92 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
  93 {
  94         return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
  95 }
  96
  97 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  98                                          bool data)
  99 {
 100         u64 vsid;
 101         struct kvmppc_pte pte;
 102
 103         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
 104                 return pte.vpage;
 105
 106         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
 107         return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
 108 }
 109
 110 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
 111 {
 112         kvmppc_set_msr(vcpu, 0);
 113 }
 114
 115 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
 116                                       u32 sre, gva_t eaddr,
 117                                       bool primary)
 118 {
 119         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 120         u32 page, hash, pteg, htabmask;
 121         hva_t r;
 122
 123         page = (eaddr & 0x0FFFFFFF) >> 12;
 124         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
 125
 126         hash = ((sr_vsid(sre) ^ page) << 6);
 127         if (!primary)
 128                 hash = ~hash;
 129         hash &= htabmask;
 130
 131         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
 132
 133         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 134                 kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
 135                 sr_vsid(sre));
 136
 137         r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
 138         if (kvm_is_error_hva(r))
 139                 return r;
 140         return r | (pteg & ~PAGE_MASK);
 141 }
 142
 143 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
 144 {
 145         return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
 146                (primary ? 0 : 0x40) | 0x80000000;
 147 }
 148
 149 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 150                                           struct kvmppc_pte *pte, bool data,
 151                                           bool iswrite)
 152 {
 153         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 154         struct kvmppc_bat *bat;
 155         int i;
 156
 157         for (i = 0; i < 8; i++) {
 158                 if (data)
 159                         bat = &vcpu_book3s->dbat[i];
 160                 else
 161                         bat = &vcpu_book3s->ibat[i];
 162
 163                 if (kvmppc_get_msr(vcpu) & MSR_PR) {
 164                         if (!bat->vp)
 165                                 continue;
 166                 } else {
 167                         if (!bat->vs)
 168                                 continue;
 169                 }
 170
 171                 if (check_debug_ip(vcpu))
 172                 {
 173                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 174                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 175                                     bat->bepi_mask);
 176                 }
 177                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 178                         u64 vsid;
 179                         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
 180                                 eaddr >> SID_SHIFT, &vsid);
 181                         vsid <<= 16;
 182                         pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
 183
 184                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 185                         pte->may_read = bat->pp;
 186                         pte->may_write = bat->pp > 1;
 187                         pte->may_execute = true;
 188                         if (!pte->may_read) {
 189                                 printk(KERN_INFO "BAT is not readable!\n");
 190                                 continue;
 191                         }
 192                         if (iswrite && !pte->may_write) {
 193                                 dprintk_pte("BAT is read-only!\n");
 194                                 continue;
 195                         }
 196
 197                         return 0;
 198                 }
 199         }
 200
 201         return -ENOENT;
 202 }
 203
 204 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 205                                      struct kvmppc_pte *pte, bool data,
 206                                      bool iswrite, bool primary)
 207 {
 208         u32 sre;
 209         hva_t ptegp;
 210         u32 pteg[16];
 211         u32 pte0, pte1;
 212         u32 ptem = 0;
 213         int i;
 214         int found = 0;
 215
 216         sre = find_sr(vcpu, eaddr);
 217
 218         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 219                     sr_vsid(sre), sre);
 220
 221         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 222
 223         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
 224         if (kvm_is_error_hva(ptegp)) {
 225                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 226                 goto no_page_found;
 227         }
 228
 229         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 230
 231         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 232                 printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
 233                 goto no_page_found;
 234         }
 235
 236         for (i=0; i<16; i+=2) {
 237                 pte0 = be32_to_cpu(pteg[i]);
 238                 pte1 = be32_to_cpu(pteg[i + 1]);
 239                 if (ptem == pte0) {
 240                         u8 pp;
 241
 242                         pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
 243                         pp = pte1 & 3;
 244
 245                         if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
 246                             (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & MSR_PR)))
 247                                 pp |= 4;
 248
 249                         pte->may_write = false;
 250                         pte->may_read = false;
 251                         pte->may_execute = true;
 252                         switch (pp) {
 253                                 case 0:
 254                                 case 1:
 255                                 case 2:
 256                                 case 6:
 257                                         pte->may_write = true;
 258                                 case 3:
 259                                 case 5:
 260                                 case 7:
 261                                         pte->may_read = true;
 262                                         break;
 263                         }
 264
 265                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 266                                     pte0, pte1, pp);
 267                         found = 1;
 268                         break;
 269                 }
 270         }
 271
 272         /* Update PTE C and A bits, so the guest's swapper knows we used the
 273            page */
 274         if (found) {
 275                 u32 pte_r = pte1;
 276                 char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
 277
 278                 /*
 279                  * Use single-byte writes to update the HPTE, to
 280                  * conform to what real hardware does.
 281                  */
 282                 if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
 283                         pte_r |= PTEG_FLAG_ACCESSED;
 284                         put_user(pte_r >> 8, addr + 2);
 285                 }
 286                 if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
 287                         pte_r |= PTEG_FLAG_DIRTY;
 288                         put_user(pte_r, addr + 3);
 289                 }
 290                 if (!pte->may_read || (iswrite && !pte->may_write))
 291                         return -EPERM;
 292                 return 0;
 293         }
 294
 295 no_page_found:
 296
 297         if (check_debug_ip(vcpu)) {
 298                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 299                             to_book3s(vcpu)->sdr1, ptegp);
 300                 for (i=0; i<16; i+=2) {
 301                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
 302                                     i, be32_to_cpu(pteg[i]),
 303                                     be32_to_cpu(pteg[i+1]), ptem);
 304                 }
 305         }
 306
 307         return -ENOENT;
 308 }
 309
 310 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 311                                       struct kvmppc_pte *pte, bool data,
 312                                       bool iswrite)
 313 {
 314         int r;
 315         ulong mp_ea = vcpu->arch.magic_page_ea;
 316
 317         pte->eaddr = eaddr;
 318         pte->page_size = MMU_PAGE_4K;
 319
 320         /* Magic page override */
 321         if (unlikely(mp_ea) &&
 322             unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
 323             !(kvmppc_get_msr(vcpu) & MSR_PR)) {
 324                 pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 325                 pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
 326                 pte->raddr &= KVM_PAM;
 327                 pte->may_execute = true;
 328                 pte->may_read = true;
 329                 pte->may_write = true;
 330
 331                 return 0;
 332         }
 333
 334         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
 335         if (r < 0)
 336                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 337                                                    data, iswrite, true);
 338         if (r == -ENOENT)
 339                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 340                                                    data, iswrite, false);
 341
 342         return r;
 343 }
 344
 345
 346 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 347 {
 348         return kvmppc_get_sr(vcpu, srnum);
 349 }
 350
 351 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 352                                         ulong value)
 353 {
 354         kvmppc_set_sr(vcpu, srnum, value);
 355         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 356 }
 357
 358 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 359 {
 360         int i;
 361         struct kvm_vcpu *v;
 362
 363         /* flush this VA on all cpus */
 364         kvm_for_each_vcpu(i, v, vcpu->kvm)
 365                 kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
 366 }
 367
 368 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
 369                                              u64 *vsid)
 370 {
 371         ulong ea = esid << SID_SHIFT;
 372         u32 sr;
 373         u64 gvsid = esid;
 374         u64 msr = kvmppc_get_msr(vcpu);
 375
 376         if (msr & (MSR_DR|MSR_IR)) {
 377                 sr = find_sr(vcpu, ea);
 378                 if (sr_valid(sr))
 379                         gvsid = sr_vsid(sr);
 380         }
 381
 382         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 383            that in the real-mode context (and hope RM doesn't access
 384            high memory) */
 385         switch (msr & (MSR_DR|MSR_IR)) {
 386         case 0:
 387                 *vsid = VSID_REAL | esid;
 388                 break;
 389         case MSR_IR:
 390                 *vsid = VSID_REAL_IR | gvsid;
 391                 break;
 392         case MSR_DR:
 393                 *vsid = VSID_REAL_DR | gvsid;
 394                 break;
 395         case MSR_DR|MSR_IR:
 396                 if (sr_valid(sr))
 397                         *vsid = sr_vsid(sr);
 398                 else
 399                         *vsid = VSID_BAT | gvsid;
 400                 break;
 401         default:
 402                 BUG();
 403         }
 404
 405         if (msr & MSR_PR)
 406                 *vsid |= VSID_PR;
 407
 408         return 0;
 409 }
 410
 411 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 412 {
 413         return true;
 414 }
 415
 416
 417 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 418 {
 419         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 420
 421         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 422         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 423         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 424         mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
 425         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 426         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 427         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 428         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 429
 430         mmu->slbmte = NULL;
 431         mmu->slbmfee = NULL;
 432         mmu->slbmfev = NULL;
 433         mmu->slbie = NULL;
 434         mmu->slbia = NULL;
 435 }