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 int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  62                                           struct kvmppc_pte *pte, bool data);
  63 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  64                                              u64 *vsid);
  65
  66 static struct kvmppc_sr *find_sr(struct kvmppc_vcpu_book3s *vcpu_book3s, gva_t eaddr)
  67 {
  68         return &vcpu_book3s->sr[(eaddr >> 28) & 0xf];
  69 }
  70
  71 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  72                                          bool data)
  73 {
  74         u64 vsid;
  75         struct kvmppc_pte pte;
  76
  77         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data))
  78                 return pte.vpage;
  79
  80         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
  81         return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
  82 }
  83
  84 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
  85 {
  86         kvmppc_set_msr(vcpu, 0);
  87 }
  88
  89 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvmppc_vcpu_book3s *vcpu_book3s,
  90                                       struct kvmppc_sr *sre, gva_t eaddr,
  91                                       bool primary)
  92 {
  93         u32 page, hash, pteg, htabmask;
  94         hva_t r;
  95
  96         page = (eaddr & 0x0FFFFFFF) >> 12;
  97         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
  98
  99         hash = ((sre->vsid ^ page) << 6);
 100         if (!primary)
 101                 hash = ~hash;
 102         hash &= htabmask;
 103
 104         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
 105
 106         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 107                 vcpu_book3s->vcpu.arch.pc, eaddr, vcpu_book3s->sdr1, pteg,
 108                 sre->vsid);
 109
 110         r = gfn_to_hva(vcpu_book3s->vcpu.kvm, pteg >> PAGE_SHIFT);
 111         if (kvm_is_error_hva(r))
 112                 return r;
 113         return r | (pteg & ~PAGE_MASK);
 114 }
 115
 116 static u32 kvmppc_mmu_book3s_32_get_ptem(struct kvmppc_sr *sre, gva_t eaddr,
 117                                     bool primary)
 118 {
 119         return ((eaddr & 0x0fffffff) >> 22) | (sre->vsid << 7) |
 120                (primary ? 0 : 0x40) | 0x80000000;
 121 }
 122
 123 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 124                                           struct kvmppc_pte *pte, bool data)
 125 {
 126         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 127         struct kvmppc_bat *bat;
 128         int i;
 129
 130         for (i = 0; i < 8; i++) {
 131                 if (data)
 132                         bat = &vcpu_book3s->dbat[i];
 133                 else
 134                         bat = &vcpu_book3s->ibat[i];
 135
 136                 if (vcpu->arch.msr & MSR_PR) {
 137                         if (!bat->vp)
 138                                 continue;
 139                 } else {
 140                         if (!bat->vs)
 141                                 continue;
 142                 }
 143
 144                 if (check_debug_ip(vcpu))
 145                 {
 146                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 147                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 148                                     bat->bepi_mask);
 149                 }
 150                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 151                         u64 vsid;
 152                         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
 153                                 eaddr >> SID_SHIFT, &vsid);
 154                         vsid <<= 16;
 155                         pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
 156
 157                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 158                         pte->may_read = bat->pp;
 159                         pte->may_write = bat->pp > 1;
 160                         pte->may_execute = true;
 161                         if (!pte->may_read) {
 162                                 printk(KERN_INFO "BAT is not readable!\n");
 163                                 continue;
 164                         }
 165                         if (!pte->may_write) {
 166                                 /* let's treat r/o BATs as not-readable for now */
 167                                 dprintk_pte("BAT is read-only!\n");
 168                                 continue;
 169                         }
 170
 171                         return 0;
 172                 }
 173         }
 174
 175         return -ENOENT;
 176 }
 177
 178 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 179                                      struct kvmppc_pte *pte, bool data,
 180                                      bool primary)
 181 {
 182         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 183         struct kvmppc_sr *sre;
 184         hva_t ptegp;
 185         u32 pteg[16];
 186         u32 ptem = 0;
 187         int i;
 188         int found = 0;
 189
 190         sre = find_sr(vcpu_book3s, eaddr);
 191
 192         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 193                     sre->vsid, sre->raw);
 194
 195         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 196
 197         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu_book3s, sre, eaddr, primary);
 198         if (kvm_is_error_hva(ptegp)) {
 199                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 200                 goto no_page_found;
 201         }
 202
 203         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 204
 205         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 206                 printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
 207                 goto no_page_found;
 208         }
 209
 210         for (i=0; i<16; i+=2) {
 211                 if (ptem == pteg[i]) {
 212                         u8 pp;
 213
 214                         pte->raddr = (pteg[i+1] & ~(0xFFFULL)) | (eaddr & 0xFFF);
 215                         pp = pteg[i+1] & 3;
 216
 217                         if ((sre->Kp &&  (vcpu->arch.msr & MSR_PR)) ||
 218                             (sre->Ks && !(vcpu->arch.msr & MSR_PR)))
 219                                 pp |= 4;
 220
 221                         pte->may_write = false;
 222                         pte->may_read = false;
 223                         pte->may_execute = true;
 224                         switch (pp) {
 225                                 case 0:
 226                                 case 1:
 227                                 case 2:
 228                                 case 6:
 229                                         pte->may_write = true;
 230                                 case 3:
 231                                 case 5:
 232                                 case 7:
 233                                         pte->may_read = true;
 234                                         break;
 235                         }
 236
 237                         if ( !pte->may_read )
 238                                 continue;
 239
 240                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 241                                     pteg[i], pteg[i+1], pp);
 242                         found = 1;
 243                         break;
 244                 }
 245         }
 246
 247         /* Update PTE C and A bits, so the guest's swapper knows we used the
 248            page */
 249         if (found) {
 250                 u32 oldpte = pteg[i+1];
 251
 252                 if (pte->may_read)
 253                         pteg[i+1] |= PTEG_FLAG_ACCESSED;
 254                 if (pte->may_write)
 255                         pteg[i+1] |= PTEG_FLAG_DIRTY;
 256                 else
 257                         dprintk_pte("KVM: Mapping read-only page!\n");
 258
 259                 /* Write back into the PTEG */
 260                 if (pteg[i+1] != oldpte)
 261                         copy_to_user((void __user *)ptegp, pteg, sizeof(pteg));
 262
 263                 return 0;
 264         }
 265
 266 no_page_found:
 267
 268         if (check_debug_ip(vcpu)) {
 269                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 270                             to_book3s(vcpu)->sdr1, ptegp);
 271                 for (i=0; i<16; i+=2) {
 272                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%llx)\n",
 273                                     i, pteg[i], pteg[i+1], ptem);
 274                 }
 275         }
 276
 277         return -ENOENT;
 278 }
 279
 280 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 281                                       struct kvmppc_pte *pte, bool data)
 282 {
 283         int r;
 284
 285         pte->eaddr = eaddr;
 286         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data);
 287         if (r < 0)
 288                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, true);
 289         if (r < 0)
 290                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, false);
 291
 292         return r;
 293 }
 294
 295
 296 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 297 {
 298         return to_book3s(vcpu)->sr[srnum].raw;
 299 }
 300
 301 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 302                                         ulong value)
 303 {
 304         struct kvmppc_sr *sre;
 305
 306         sre = &to_book3s(vcpu)->sr[srnum];
 307
 308         /* Flush any left-over shadows from the previous SR */
 309
 310         /* XXX Not necessary? */
 311         /* kvmppc_mmu_pte_flush(vcpu, ((u64)sre->vsid) << 28, 0xf0000000ULL); */
 312
 313         /* And then put in the new SR */
 314         sre->raw = value;
 315         sre->vsid = (value & 0x0fffffff);
 316         sre->valid = (value & 0x80000000) ? false : true;
 317         sre->Ks = (value & 0x40000000) ? true : false;
 318         sre->Kp = (value & 0x20000000) ? true : false;
 319         sre->nx = (value & 0x10000000) ? true : false;
 320
 321         /* Map the new segment */
 322         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 323 }
 324
 325 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 326 {
 327         kvmppc_mmu_pte_flush(vcpu, ea, 0x0FFFF000);
 328 }
 329
 330 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
 331                                              u64 *vsid)
 332 {
 333         ulong ea = esid << SID_SHIFT;
 334         struct kvmppc_sr *sr;
 335         u64 gvsid = esid;
 336
 337         if (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
 338                 sr = find_sr(to_book3s(vcpu), ea);
 339                 if (sr->valid)
 340                         gvsid = sr->vsid;
 341         }
 342
 343         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 344            that in the real-mode context (and hope RM doesn't access
 345            high memory) */
 346         switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
 347         case 0:
 348                 *vsid = VSID_REAL | esid;
 349                 break;
 350         case MSR_IR:
 351                 *vsid = VSID_REAL_IR | gvsid;
 352                 break;
 353         case MSR_DR:
 354                 *vsid = VSID_REAL_DR | gvsid;
 355                 break;
 356         case MSR_DR|MSR_IR:
 357                 if (!sr->valid)
 358                         return -1;
 359
 360                 *vsid = sr->vsid;
 361                 break;
 362         default:
 363                 BUG();
 364         }
 365
 366         if (vcpu->arch.msr & MSR_PR)
 367                 *vsid |= VSID_PR;
 368
 369         return 0;
 370 }
 371
 372 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 373 {
 374         return true;
 375 }
 376
 377
 378 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 379 {
 380         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 381
 382         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 383         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 384         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 385         mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
 386         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 387         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 388         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 389         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 390
 391         mmu->slbmte = NULL;
 392         mmu->slbmfee = NULL;
 393         mmu->slbmfev = NULL;
 394         mmu->slbie = NULL;
 395         mmu->slbia = NULL;
 396 }