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 int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  82                                           struct kvmppc_pte *pte, bool data,
  83                                           bool iswrite);
  84 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  85                                              u64 *vsid);
  86
  87 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
  88 {
  89         return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
  90 }
  91
  92 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  93                                          bool data)
  94 {
  95         u64 vsid;
  96         struct kvmppc_pte pte;
  97
  98         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
  99                 return pte.vpage;
 100
 101         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
 102         return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
 103 }
 104
 105 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
 106 {
 107         kvmppc_set_msr(vcpu, 0);
 108 }
 109
 110 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
 111                                       u32 sre, gva_t eaddr,
 112                                       bool primary)
 113 {
 114         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 115         u32 page, hash, pteg, htabmask;
 116         hva_t r;
 117
 118         page = (eaddr & 0x0FFFFFFF) >> 12;
 119         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
 120
 121         hash = ((sr_vsid(sre) ^ page) << 6);
 122         if (!primary)
 123                 hash = ~hash;
 124         hash &= htabmask;
 125
 126         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
 127
 128         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 129                 kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
 130                 sr_vsid(sre));
 131
 132         r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
 133         if (kvm_is_error_hva(r))
 134                 return r;
 135         return r | (pteg & ~PAGE_MASK);
 136 }
 137
 138 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
 139 {
 140         return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
 141                (primary ? 0 : 0x40) | 0x80000000;
 142 }
 143
 144 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 145                                           struct kvmppc_pte *pte, bool data,
 146                                           bool iswrite)
 147 {
 148         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 149         struct kvmppc_bat *bat;
 150         int i;
 151
 152         for (i = 0; i < 8; i++) {
 153                 if (data)
 154                         bat = &vcpu_book3s->dbat[i];
 155                 else
 156                         bat = &vcpu_book3s->ibat[i];
 157
 158                 if (kvmppc_get_msr(vcpu) & MSR_PR) {
 159                         if (!bat->vp)
 160                                 continue;
 161                 } else {
 162                         if (!bat->vs)
 163                                 continue;
 164                 }
 165
 166                 if (check_debug_ip(vcpu))
 167                 {
 168                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 169                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 170                                     bat->bepi_mask);
 171                 }
 172                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 173                         u64 vsid;
 174                         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
 175                                 eaddr >> SID_SHIFT, &vsid);
 176                         vsid <<= 16;
 177                         pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
 178
 179                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 180                         pte->may_read = bat->pp;
 181                         pte->may_write = bat->pp > 1;
 182                         pte->may_execute = true;
 183                         if (!pte->may_read) {
 184                                 printk(KERN_INFO "BAT is not readable!\n");
 185                                 continue;
 186                         }
 187                         if (iswrite && !pte->may_write) {
 188                                 dprintk_pte("BAT is read-only!\n");
 189                                 continue;
 190                         }
 191
 192                         return 0;
 193                 }
 194         }
 195
 196         return -ENOENT;
 197 }
 198
 199 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 200                                      struct kvmppc_pte *pte, bool data,
 201                                      bool iswrite, bool primary)
 202 {
 203         u32 sre;
 204         hva_t ptegp;
 205         u32 pteg[16];
 206         u32 pte0, pte1;
 207         u32 ptem = 0;
 208         int i;
 209         int found = 0;
 210
 211         sre = find_sr(vcpu, eaddr);
 212
 213         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 214                     sr_vsid(sre), sre);
 215
 216         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 217
 218         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
 219         if (kvm_is_error_hva(ptegp)) {
 220                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 221                 goto no_page_found;
 222         }
 223
 224         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 225
 226         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 227                 printk_ratelimited(KERN_ERR
 228                         "KVM: Can't copy data from 0x%lx!\n", ptegp);
 229                 goto no_page_found;
 230         }
 231
 232         for (i=0; i<16; i+=2) {
 233                 pte0 = be32_to_cpu(pteg[i]);
 234                 pte1 = be32_to_cpu(pteg[i + 1]);
 235                 if (ptem == pte0) {
 236                         u8 pp;
 237
 238                         pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
 239                         pp = pte1 & 3;
 240
 241                         if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
 242                             (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & 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                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 262                                     pte0, pte1, pp);
 263                         found = 1;
 264                         break;
 265                 }
 266         }
 267
 268         /* Update PTE C and A bits, so the guest's swapper knows we used the
 269            page */
 270         if (found) {
 271                 u32 pte_r = pte1;
 272                 char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
 273
 274                 /*
 275                  * Use single-byte writes to update the HPTE, to
 276                  * conform to what real hardware does.
 277                  */
 278                 if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
 279                         pte_r |= PTEG_FLAG_ACCESSED;
 280                         put_user(pte_r >> 8, addr + 2);
 281                 }
 282                 if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
 283                         pte_r |= PTEG_FLAG_DIRTY;
 284                         put_user(pte_r, addr + 3);
 285                 }
 286                 if (!pte->may_read || (iswrite && !pte->may_write))
 287                         return -EPERM;
 288                 return 0;
 289         }
 290
 291 no_page_found:
 292
 293         if (check_debug_ip(vcpu)) {
 294                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 295                             to_book3s(vcpu)->sdr1, ptegp);
 296                 for (i=0; i<16; i+=2) {
 297                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
 298                                     i, be32_to_cpu(pteg[i]),
 299                                     be32_to_cpu(pteg[i+1]), ptem);
 300                 }
 301         }
 302
 303         return -ENOENT;
 304 }
 305
 306 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 307                                       struct kvmppc_pte *pte, bool data,
 308                                       bool iswrite)
 309 {
 310         int r;
 311         ulong mp_ea = vcpu->arch.magic_page_ea;
 312
 313         pte->eaddr = eaddr;
 314         pte->page_size = MMU_PAGE_4K;
 315
 316         /* Magic page override */
 317         if (unlikely(mp_ea) &&
 318             unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
 319             !(kvmppc_get_msr(vcpu) & MSR_PR)) {
 320                 pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 321                 pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
 322                 pte->raddr &= KVM_PAM;
 323                 pte->may_execute = true;
 324                 pte->may_read = true;
 325                 pte->may_write = true;
 326
 327                 return 0;
 328         }
 329
 330         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
 331         if (r < 0)
 332                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 333                                                    data, iswrite, true);
 334         if (r == -ENOENT)
 335                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 336                                                    data, iswrite, false);
 337
 338         return r;
 339 }
 340
 341
 342 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 343 {
 344         return kvmppc_get_sr(vcpu, srnum);
 345 }
 346
 347 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 348                                         ulong value)
 349 {
 350         kvmppc_set_sr(vcpu, srnum, value);
 351         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 352 }
 353
 354 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 355 {
 356         int i;
 357         struct kvm_vcpu *v;
 358
 359         /* flush this VA on all cpus */
 360         kvm_for_each_vcpu(i, v, vcpu->kvm)
 361                 kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
 362 }
 363
 364 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
 365                                              u64 *vsid)
 366 {
 367         ulong ea = esid << SID_SHIFT;
 368         u32 sr;
 369         u64 gvsid = esid;
 370         u64 msr = kvmppc_get_msr(vcpu);
 371
 372         if (msr & (MSR_DR|MSR_IR)) {
 373                 sr = find_sr(vcpu, ea);
 374                 if (sr_valid(sr))
 375                         gvsid = sr_vsid(sr);
 376         }
 377
 378         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 379            that in the real-mode context (and hope RM doesn't access
 380            high memory) */
 381         switch (msr & (MSR_DR|MSR_IR)) {
 382         case 0:
 383                 *vsid = VSID_REAL | esid;
 384                 break;
 385         case MSR_IR:
 386                 *vsid = VSID_REAL_IR | gvsid;
 387                 break;
 388         case MSR_DR:
 389                 *vsid = VSID_REAL_DR | gvsid;
 390                 break;
 391         case MSR_DR|MSR_IR:
 392                 if (sr_valid(sr))
 393                         *vsid = sr_vsid(sr);
 394                 else
 395                         *vsid = VSID_BAT | gvsid;
 396                 break;
 397         default:
 398                 BUG();
 399         }
 400
 401         if (msr & MSR_PR)
 402                 *vsid |= VSID_PR;
 403
 404         return 0;
 405 }
 406
 407 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 408 {
 409         return true;
 410 }
 411
 412
 413 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 414 {
 415         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 416
 417         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 418         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 419         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 420         mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
 421         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 422         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 423         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 424         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 425
 426         mmu->slbmte = NULL;
 427         mmu->slbmfee = NULL;
 428         mmu->slbmfev = NULL;
 429         mmu->slbie = NULL;
 430         mmu->slbia = NULL;
 431 }