arch/powerpc/kvm/book3s_32_mmu.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *
   4  * Copyright SUSE Linux Products GmbH 2009
   5  *
   6  * Authors: Alexander Graf <agraf@suse.de>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/string.h>
  11 #include <linux/kvm.h>
  12 #include <linux/kvm_host.h>
  13 #include <linux/highmem.h>
  14
  15 #include <asm/kvm_ppc.h>
  16 #include <asm/kvm_book3s.h>
  17
  18 /* #define DEBUG_MMU */
  19 /* #define DEBUG_MMU_PTE */
  20 /* #define DEBUG_MMU_PTE_IP 0xfff14c40 */
  21
  22 #ifdef DEBUG_MMU
  23 #define dprintk(X...) printk(KERN_INFO X)
  24 #else
  25 #define dprintk(X...) do { } while(0)
  26 #endif
  27
  28 #ifdef DEBUG_MMU_PTE
  29 #define dprintk_pte(X...) printk(KERN_INFO X)
  30 #else
  31 #define dprintk_pte(X...) do { } while(0)
  32 #endif
  33
  34 #define PTEG_FLAG_ACCESSED      0x00000100
  35 #define PTEG_FLAG_DIRTY         0x00000080
  36 #ifndef SID_SHIFT
  37 #define SID_SHIFT               28
  38 #endif
  39
  40 static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
  41 {
  42 #ifdef DEBUG_MMU_PTE_IP
  43         return vcpu->arch.regs.nip == DEBUG_MMU_PTE_IP;
  44 #else
  45         return true;
  46 #endif
  47 }
  48
  49 static inline u32 sr_vsid(u32 sr_raw)
  50 {
  51         return sr_raw & 0x0fffffff;
  52 }
  53
  54 static inline bool sr_valid(u32 sr_raw)
  55 {
  56         return (sr_raw & 0x80000000) ? false : true;
  57 }
  58
  59 static inline bool sr_ks(u32 sr_raw)
  60 {
  61         return (sr_raw & 0x40000000) ? true: false;
  62 }
  63
  64 static inline bool sr_kp(u32 sr_raw)
  65 {
  66         return (sr_raw & 0x20000000) ? true: false;
  67 }
  68
  69 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  70                                           struct kvmppc_pte *pte, bool data,
  71                                           bool iswrite);
  72 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  73                                              u64 *vsid);
  74
  75 static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
  76 {
  77         return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
  78 }
  79
  80 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  81                                          bool data)
  82 {
  83         u64 vsid;
  84         struct kvmppc_pte pte;
  85
  86         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data, false))
  87                 return pte.vpage;
  88
  89         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
  90         return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
  91 }
  92
  93 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
  94                                       u32 sre, gva_t eaddr,
  95                                       bool primary)
  96 {
  97         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
  98         u32 page, hash, pteg, htabmask;
  99         hva_t r;
 100
 101         page = (eaddr & 0x0FFFFFFF) >> 12;
 102         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
 103
 104         hash = ((sr_vsid(sre) ^ page) << 6);
 105         if (!primary)
 106                 hash = ~hash;
 107         hash &= htabmask;
 108
 109         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
 110
 111         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 112                 kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
 113                 sr_vsid(sre));
 114
 115         r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);
 116         if (kvm_is_error_hva(r))
 117                 return r;
 118         return r | (pteg & ~PAGE_MASK);
 119 }
 120
 121 static u32 kvmppc_mmu_book3s_32_get_ptem(u32 sre, gva_t eaddr, bool primary)
 122 {
 123         return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 7) |
 124                (primary ? 0 : 0x40) | 0x80000000;
 125 }
 126
 127 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 128                                           struct kvmppc_pte *pte, bool data,
 129                                           bool iswrite)
 130 {
 131         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 132         struct kvmppc_bat *bat;
 133         int i;
 134
 135         for (i = 0; i < 8; i++) {
 136                 if (data)
 137                         bat = &vcpu_book3s->dbat[i];
 138                 else
 139                         bat = &vcpu_book3s->ibat[i];
 140
 141                 if (kvmppc_get_msr(vcpu) & MSR_PR) {
 142                         if (!bat->vp)
 143                                 continue;
 144                 } else {
 145                         if (!bat->vs)
 146                                 continue;
 147                 }
 148
 149                 if (check_debug_ip(vcpu))
 150                 {
 151                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 152                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 153                                     bat->bepi_mask);
 154                 }
 155                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 156                         u64 vsid;
 157                         kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
 158                                 eaddr >> SID_SHIFT, &vsid);
 159                         vsid <<= 16;
 160                         pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
 161
 162                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 163                         pte->may_read = bat->pp;
 164                         pte->may_write = bat->pp > 1;
 165                         pte->may_execute = true;
 166                         if (!pte->may_read) {
 167                                 printk(KERN_INFO "BAT is not readable!\n");
 168                                 continue;
 169                         }
 170                         if (iswrite && !pte->may_write) {
 171                                 dprintk_pte("BAT is read-only!\n");
 172                                 continue;
 173                         }
 174
 175                         return 0;
 176                 }
 177         }
 178
 179         return -ENOENT;
 180 }
 181
 182 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 183                                      struct kvmppc_pte *pte, bool data,
 184                                      bool iswrite, bool primary)
 185 {
 186         u32 sre;
 187         hva_t ptegp;
 188         u32 pteg[16];
 189         u32 pte0, pte1;
 190         u32 ptem = 0;
 191         int i;
 192         int found = 0;
 193
 194         sre = find_sr(vcpu, eaddr);
 195
 196         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 197                     sr_vsid(sre), sre);
 198
 199         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 200
 201         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, sre, eaddr, primary);
 202         if (kvm_is_error_hva(ptegp)) {
 203                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 204                 goto no_page_found;
 205         }
 206
 207         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 208
 209         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 210                 printk_ratelimited(KERN_ERR
 211                         "KVM: Can't copy data from 0x%lx!\n", ptegp);
 212                 goto no_page_found;
 213         }
 214
 215         for (i=0; i<16; i+=2) {
 216                 pte0 = be32_to_cpu(pteg[i]);
 217                 pte1 = be32_to_cpu(pteg[i + 1]);
 218                 if (ptem == pte0) {
 219                         u8 pp;
 220
 221                         pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
 222                         pp = pte1 & 3;
 223
 224                         if ((sr_kp(sre) &&  (kvmppc_get_msr(vcpu) & MSR_PR)) ||
 225                             (sr_ks(sre) && !(kvmppc_get_msr(vcpu) & MSR_PR)))
 226                                 pp |= 4;
 227
 228                         pte->may_write = false;
 229                         pte->may_read = false;
 230                         pte->may_execute = true;
 231                         switch (pp) {
 232                                 case 0:
 233                                 case 1:
 234                                 case 2:
 235                                 case 6:
 236                                         pte->may_write = true;
 237                                         fallthrough;
 238                                 case 3:
 239                                 case 5:
 240                                 case 7:
 241                                         pte->may_read = true;
 242                                         break;
 243                         }
 244
 245                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 246                                     pte0, pte1, pp);
 247                         found = 1;
 248                         break;
 249                 }
 250         }
 251
 252         /* Update PTE C and A bits, so the guest's swapper knows we used the
 253            page */
 254         if (found) {
 255                 u32 pte_r = pte1;
 256                 char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
 257
 258                 /*
 259                  * Use single-byte writes to update the HPTE, to
 260                  * conform to what real hardware does.
 261                  */
 262                 if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
 263                         pte_r |= PTEG_FLAG_ACCESSED;
 264                         put_user(pte_r >> 8, addr + 2);
 265                 }
 266                 if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
 267                         pte_r |= PTEG_FLAG_DIRTY;
 268                         put_user(pte_r, addr + 3);
 269                 }
 270                 if (!pte->may_read || (iswrite && !pte->may_write))
 271                         return -EPERM;
 272                 return 0;
 273         }
 274
 275 no_page_found:
 276
 277         if (check_debug_ip(vcpu)) {
 278                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 279                             to_book3s(vcpu)->sdr1, ptegp);
 280                 for (i=0; i<16; i+=2) {
 281                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%x)\n",
 282                                     i, be32_to_cpu(pteg[i]),
 283                                     be32_to_cpu(pteg[i+1]), ptem);
 284                 }
 285         }
 286
 287         return -ENOENT;
 288 }
 289
 290 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 291                                       struct kvmppc_pte *pte, bool data,
 292                                       bool iswrite)
 293 {
 294         int r;
 295         ulong mp_ea = vcpu->arch.magic_page_ea;
 296
 297         pte->eaddr = eaddr;
 298         pte->page_size = MMU_PAGE_4K;
 299
 300         /* Magic page override */
 301         if (unlikely(mp_ea) &&
 302             unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
 303             !(kvmppc_get_msr(vcpu) & MSR_PR)) {
 304                 pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 305                 pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
 306                 pte->raddr &= KVM_PAM;
 307                 pte->may_execute = true;
 308                 pte->may_read = true;
 309                 pte->may_write = true;
 310
 311                 return 0;
 312         }
 313
 314         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
 315         if (r < 0)
 316                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 317                                                    data, iswrite, true);
 318         if (r == -ENOENT)
 319                 r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
 320                                                    data, iswrite, false);
 321
 322         return r;
 323 }
 324
 325
 326 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 327 {
 328         return kvmppc_get_sr(vcpu, srnum);
 329 }
 330
 331 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 332                                         ulong value)
 333 {
 334         kvmppc_set_sr(vcpu, srnum, value);
 335         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 336 }
 337
 338 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 339 {
 340         int i;
 341         struct kvm_vcpu *v;
 342
 343         /* flush this VA on all cpus */
 344         kvm_for_each_vcpu(i, v, vcpu->kvm)
 345                 kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
 346 }
 347
 348 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
 349                                              u64 *vsid)
 350 {
 351         ulong ea = esid << SID_SHIFT;
 352         u32 sr;
 353         u64 gvsid = esid;
 354         u64 msr = kvmppc_get_msr(vcpu);
 355
 356         if (msr & (MSR_DR|MSR_IR)) {
 357                 sr = find_sr(vcpu, ea);
 358                 if (sr_valid(sr))
 359                         gvsid = sr_vsid(sr);
 360         }
 361
 362         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 363            that in the real-mode context (and hope RM doesn't access
 364            high memory) */
 365         switch (msr & (MSR_DR|MSR_IR)) {
 366         case 0:
 367                 *vsid = VSID_REAL | esid;
 368                 break;
 369         case MSR_IR:
 370                 *vsid = VSID_REAL_IR | gvsid;
 371                 break;
 372         case MSR_DR:
 373                 *vsid = VSID_REAL_DR | gvsid;
 374                 break;
 375         case MSR_DR|MSR_IR:
 376                 if (sr_valid(sr))
 377                         *vsid = sr_vsid(sr);
 378                 else
 379                         *vsid = VSID_BAT | gvsid;
 380                 break;
 381         default:
 382                 BUG();
 383         }
 384
 385         if (msr & MSR_PR)
 386                 *vsid |= VSID_PR;
 387
 388         return 0;
 389 }
 390
 391 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 392 {
 393         return true;
 394 }
 395
 396
 397 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 398 {
 399         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 400
 401         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 402         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 403         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 404         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 405         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 406         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 407         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 408
 409         mmu->slbmte = NULL;
 410         mmu->slbmfee = NULL;
 411         mmu->slbmfev = NULL;
 412         mmu->slbfee = NULL;
 413         mmu->slbie = NULL;
 414         mmu->slbia = NULL;
 415 }