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 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  89                                              u64 *vsid);
  90
  91 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
  92 {
  93         return vcpu->arch.shared->sr[(eaddr >> 28) & 0xf];
  94 }
  95
  96 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  97                                          bool data)
  98 {
  99         u64 vsid;
 100         struct kvmppc_pte pte;
 101
 102         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data))
 103                 return pte.vpage;
 104
 105         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
 106         return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
 107 }
 108
 109 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
 110 {
 111         kvmppc_set_msr(vcpu, 0);
 112 }
 113
 114 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvmppc_vcpu_book3s *vcpu_book3s,
 115                                       u32 sre, gva_t eaddr,
 116                                       bool primary)
 117 {
 118         u32 page, hash, pteg, htabmask;
 119         hva_t r;
 120
 121         page = (eaddr & 0x0FFFFFFF) >> 12;
 122         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
 123
 124         hash = ((sr_vsid(sre) ^ page) << 6);
 125         if (!primary)
 126                 hash = ~hash;
 127         hash &= htabmask;
 128
 129         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
 130
 131         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 132                 kvmppc_get_pc(&vcpu_book3s->vcpu), eaddr, vcpu_book3s->sdr1, pteg,
 133                 sr_vsid(sre));
 134
 135         r = gfn_to_hva(vcpu_book3s->vcpu.kvm, pteg >> PAGE_SHIFT);
 136         if (kvm_is_error_hva(r))
 137                 return r;
 138         return r | (pteg & ~PAGE_MASK);
 139 }
 140
 141 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
 142 {
 143         return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
 144                (primary ? 0 : 0x40) | 0x80000000;
 145 }
 146
 147 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 148                                           struct kvmppc_pte *pte, bool data)
 149 {
 150         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 151         struct kvmppc_bat *bat;
 152         int i;
 153
 154         for (i = 0; i < 8; i++) {
 155                 if (data)
 156                         bat = &vcpu_book3s->dbat[i];
 157                 else
 158                         bat = &vcpu_book3s->ibat[i];
 159
 160                 if (vcpu->arch.shared->msr & MSR_PR) {
 161                         if (!bat->vp)
 162                                 continue;
 163                 } else {
 164                         if (!bat->vs)
 165                                 continue;
 166                 }
 167
 168                 if (check_debug_ip(vcpu))
 169                 {
 170                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 171                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 172                                     bat->bepi_mask);
 173                 }
 174                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 175                         u64 vsid;
 176                         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
 177                                 eaddr >> SID_SHIFT, &vsid);
 178                         vsid <<= 16;
 179                         pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
 180
 181                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 182                         pte->may_read = bat->pp;
 183                         pte->may_write = bat->pp > 1;
 184                         pte->may_execute = true;
 185                         if (!pte->may_read) {
 186                                 printk(KERN_INFO "BAT is not readable!\n");
 187                                 continue;
 188                         }
 189                         if (!pte->may_write) {
 190                                 /* let's treat r/o BATs as not-readable for now */
 191                                 dprintk_pte("BAT is read-only!\n");
 192                                 continue;
 193                         }
 194
 195                         return 0;
 196                 }
 197         }
 198
 199         return -ENOENT;
 200 }
 201
 202 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 203                                      struct kvmppc_pte *pte, bool data,
 204                                      bool primary)
 205 {
 206         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 207         u32 sre;
 208         hva_t ptegp;
 209         u32 pteg[16];
 210         u32 ptem = 0;
 211         int i;
 212         int found = 0;
 213
 214         sre = find_sr(vcpu, eaddr);
 215
 216         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 217                     sr_vsid(sre), sre);
 218
 219         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 220
 221         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu_book3s, sre, eaddr, primary);
 222         if (kvm_is_error_hva(ptegp)) {
 223                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 224                 goto no_page_found;
 225         }
 226
 227         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 228
 229         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 230                 printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
 231                 goto no_page_found;
 232         }
 233
 234         for (i=0; i<16; i+=2) {
 235                 if (ptem == pteg[i]) {
 236                         u8 pp;
 237
 238                         pte->raddr = (pteg[i+1] & ~(0xFFFULL)) | (eaddr & 0xFFF);
 239                         pp = pteg[i+1] & 3;
 240
 241                         if ((sr_kp(sre) &&  (vcpu->arch.shared->msr & MSR_PR)) ||
 242                             (sr_ks(sre) && !(vcpu->arch.shared->msr & MSR_PR)))
 243                                 pp |= 4;
 244
 245                         pte->may_write = false;
 246                         pte->may_read = false;
 247                         pte->may_execute = true;
 248                         switch (pp) {
 249                                 case 0:
 250                                 case 1:
 251                                 case 2:
 252                                 case 6:
 253                                         pte->may_write = true;
 254                                 case 3:
 255                                 case 5:
 256                                 case 7:
 257                                         pte->may_read = true;
 258                                         break;
 259                         }
 260
 261                         if ( !pte->may_read )
 262                                 continue;
 263
 264                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 265                                     pteg[i], pteg[i+1], pp);
 266                         found = 1;
 267                         break;
 268                 }
 269         }
 270
 271         /* Update PTE C and A bits, so the guest's swapper knows we used the
 272            page */
 273         if (found) {
 274                 u32 oldpte = pteg[i+1];
 275
 276                 if (pte->may_read)
 277                         pteg[i+1] |= PTEG_FLAG_ACCESSED;
 278                 if (pte->may_write)
 279                         pteg[i+1] |= PTEG_FLAG_DIRTY;
 280                 else
 281                         dprintk_pte("KVM: Mapping read-only page!\n");
 282
 283                 /* Write back into the PTEG */
 284                 if (pteg[i+1] != oldpte)
 285                         copy_to_user((void __user *)ptegp, pteg, sizeof(pteg));
 286
 287                 return 0;
 288         }
 289
 290 no_page_found:
 291
 292         if (check_debug_ip(vcpu)) {
 293                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 294                             to_book3s(vcpu)->sdr1, ptegp);
 295                 for (i=0; i<16; i+=2) {
 296                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
 297                                     i, pteg[i], pteg[i+1], ptem);
 298                 }
 299         }
 300
 301         return -ENOENT;
 302 }
 303
 304 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 305                                       struct kvmppc_pte *pte, bool data)
 306 {
 307         int r;
 308         ulong mp_ea = vcpu->arch.magic_page_ea;
 309
 310         pte->eaddr = eaddr;
 311
 312         /* Magic page override */
 313         if (unlikely(mp_ea) &&
 314             unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
 315             !(vcpu->arch.shared->msr & MSR_PR)) {
 316                 pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 317                 pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
 318                 pte->raddr &= KVM_PAM;
 319                 pte->may_execute = true;
 320                 pte->may_read = true;
 321                 pte->may_write = true;
 322
 323                 return 0;
 324         }
 325
 326         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data);
 327         if (r < 0)
 328                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, true);
 329         if (r < 0)
 330                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, false);
 331
 332         return r;
 333 }
 334
 335
 336 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 337 {
 338         return vcpu->arch.shared->sr[srnum];
 339 }
 340
 341 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 342                                         ulong value)
 343 {
 344         vcpu->arch.shared->sr[srnum] = value;
 345         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 346 }
 347
 348 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 349 {
 350         kvmppc_mmu_pte_flush(vcpu, ea, 0x0FFFF000);
 351 }
 352
 353 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
 354                                              u64 *vsid)
 355 {
 356         ulong ea = esid << SID_SHIFT;
 357         u32 sr;
 358         u64 gvsid = esid;
 359
 360         if (vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) {
 361                 sr = find_sr(vcpu, ea);
 362                 if (sr_valid(sr))
 363                         gvsid = sr_vsid(sr);
 364         }
 365
 366         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 367            that in the real-mode context (and hope RM doesn't access
 368            high memory) */
 369         switch (vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) {
 370         case 0:
 371                 *vsid = VSID_REAL | esid;
 372                 break;
 373         case MSR_IR:
 374                 *vsid = VSID_REAL_IR | gvsid;
 375                 break;
 376         case MSR_DR:
 377                 *vsid = VSID_REAL_DR | gvsid;
 378                 break;
 379         case MSR_DR|MSR_IR:
 380                 if (sr_valid(sr))
 381                         *vsid = sr_vsid(sr);
 382                 else
 383                         *vsid = VSID_BAT | gvsid;
 384                 break;
 385         default:
 386                 BUG();
 387         }
 388
 389         if (vcpu->arch.shared->msr & MSR_PR)
 390                 *vsid |= VSID_PR;
 391
 392         return 0;
 393 }
 394
 395 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 396 {
 397         return true;
 398 }
 399
 400
 401 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 402 {
 403         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 404
 405         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 406         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 407         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 408         mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
 409         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 410         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 411         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 412         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 413
 414         mmu->slbmte = NULL;
 415         mmu->slbmfee = NULL;
 416         mmu->slbmfev = NULL;
 417         mmu->slbie = NULL;
 418         mmu->slbia = NULL;
 419 }