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_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
  49 static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
  50 {
  51 #ifdef DEBUG_MMU_PTE_IP
  52         return vcpu->arch.pc == DEBUG_MMU_PTE_IP;
  53 #else
  54         return true;
  55 #endif
  56 }
  57
  58 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  59                                           struct kvmppc_pte *pte, bool data);
  60
  61 static struct kvmppc_sr *find_sr(struct kvmppc_vcpu_book3s *vcpu_book3s, gva_t eaddr)
  62 {
  63         return &vcpu_book3s->sr[(eaddr >> 28) & 0xf];
  64 }
  65
  66 static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
  67                                          bool data)
  68 {
  69         struct kvmppc_sr *sre = find_sr(to_book3s(vcpu), eaddr);
  70         struct kvmppc_pte pte;
  71
  72         if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data))
  73                 return pte.vpage;
  74
  75         return (((u64)eaddr >> 12) & 0xffff) | (((u64)sre->vsid) << 16);
  76 }
  77
  78 static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
  79 {
  80         kvmppc_set_msr(vcpu, 0);
  81 }
  82
  83 static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvmppc_vcpu_book3s *vcpu_book3s,
  84                                       struct kvmppc_sr *sre, gva_t eaddr,
  85                                       bool primary)
  86 {
  87         u32 page, hash, pteg, htabmask;
  88         hva_t r;
  89
  90         page = (eaddr & 0x0FFFFFFF) >> 12;
  91         htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
  92
  93         hash = ((sre->vsid ^ page) << 6);
  94         if (!primary)
  95                 hash = ~hash;
  96         hash &= htabmask;
  97
  98         pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
  99
 100         dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
 101                 vcpu_book3s->vcpu.arch.pc, eaddr, vcpu_book3s->sdr1, pteg,
 102                 sre->vsid);
 103
 104         r = gfn_to_hva(vcpu_book3s->vcpu.kvm, pteg >> PAGE_SHIFT);
 105         if (kvm_is_error_hva(r))
 106                 return r;
 107         return r | (pteg & ~PAGE_MASK);
 108 }
 109
 110 static u32 kvmppc_mmu_book3s_32_get_ptem(struct kvmppc_sr *sre, gva_t eaddr,
 111                                     bool primary)
 112 {
 113         return ((eaddr & 0x0fffffff) >> 22) | (sre->vsid << 7) |
 114                (primary ? 0 : 0x40) | 0x80000000;
 115 }
 116
 117 static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
 118                                           struct kvmppc_pte *pte, bool data)
 119 {
 120         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 121         struct kvmppc_bat *bat;
 122         int i;
 123
 124         for (i = 0; i < 8; i++) {
 125                 if (data)
 126                         bat = &vcpu_book3s->dbat[i];
 127                 else
 128                         bat = &vcpu_book3s->ibat[i];
 129
 130                 if (vcpu->arch.msr & MSR_PR) {
 131                         if (!bat->vp)
 132                                 continue;
 133                 } else {
 134                         if (!bat->vs)
 135                                 continue;
 136                 }
 137
 138                 if (check_debug_ip(vcpu))
 139                 {
 140                         dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
 141                                     data ? 'd' : 'i', i, eaddr, bat->bepi,
 142                                     bat->bepi_mask);
 143                 }
 144                 if ((eaddr & bat->bepi_mask) == bat->bepi) {
 145                         pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
 146                         pte->vpage = (eaddr >> 12) | VSID_BAT;
 147                         pte->may_read = bat->pp;
 148                         pte->may_write = bat->pp > 1;
 149                         pte->may_execute = true;
 150                         if (!pte->may_read) {
 151                                 printk(KERN_INFO "BAT is not readable!\n");
 152                                 continue;
 153                         }
 154                         if (!pte->may_write) {
 155                                 /* let's treat r/o BATs as not-readable for now */
 156                                 dprintk_pte("BAT is read-only!\n");
 157                                 continue;
 158                         }
 159
 160                         return 0;
 161                 }
 162         }
 163
 164         return -ENOENT;
 165 }
 166
 167 static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
 168                                      struct kvmppc_pte *pte, bool data,
 169                                      bool primary)
 170 {
 171         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 172         struct kvmppc_sr *sre;
 173         hva_t ptegp;
 174         u32 pteg[16];
 175         u64 ptem = 0;
 176         int i;
 177         int found = 0;
 178
 179         sre = find_sr(vcpu_book3s, eaddr);
 180
 181         dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
 182                     sre->vsid, sre->raw);
 183
 184         pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
 185
 186         ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu_book3s, sre, eaddr, primary);
 187         if (kvm_is_error_hva(ptegp)) {
 188                 printk(KERN_INFO "KVM: Invalid PTEG!\n");
 189                 goto no_page_found;
 190         }
 191
 192         ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
 193
 194         if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
 195                 printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
 196                 goto no_page_found;
 197         }
 198
 199         for (i=0; i<16; i+=2) {
 200                 if (ptem == pteg[i]) {
 201                         u8 pp;
 202
 203                         pte->raddr = (pteg[i+1] & ~(0xFFFULL)) | (eaddr & 0xFFF);
 204                         pp = pteg[i+1] & 3;
 205
 206                         if ((sre->Kp &&  (vcpu->arch.msr & MSR_PR)) ||
 207                             (sre->Ks && !(vcpu->arch.msr & MSR_PR)))
 208                                 pp |= 4;
 209
 210                         pte->may_write = false;
 211                         pte->may_read = false;
 212                         pte->may_execute = true;
 213                         switch (pp) {
 214                                 case 0:
 215                                 case 1:
 216                                 case 2:
 217                                 case 6:
 218                                         pte->may_write = true;
 219                                 case 3:
 220                                 case 5:
 221                                 case 7:
 222                                         pte->may_read = true;
 223                                         break;
 224                         }
 225
 226                         if ( !pte->may_read )
 227                                 continue;
 228
 229                         dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
 230                                     pteg[i], pteg[i+1], pp);
 231                         found = 1;
 232                         break;
 233                 }
 234         }
 235
 236         /* Update PTE C and A bits, so the guest's swapper knows we used the
 237            page */
 238         if (found) {
 239                 u32 oldpte = pteg[i+1];
 240
 241                 if (pte->may_read)
 242                         pteg[i+1] |= PTEG_FLAG_ACCESSED;
 243                 if (pte->may_write)
 244                         pteg[i+1] |= PTEG_FLAG_DIRTY;
 245                 else
 246                         dprintk_pte("KVM: Mapping read-only page!\n");
 247
 248                 /* Write back into the PTEG */
 249                 if (pteg[i+1] != oldpte)
 250                         copy_to_user((void __user *)ptegp, pteg, sizeof(pteg));
 251
 252                 return 0;
 253         }
 254
 255 no_page_found:
 256
 257         if (check_debug_ip(vcpu)) {
 258                 dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
 259                             to_book3s(vcpu)->sdr1, ptegp);
 260                 for (i=0; i<16; i+=2) {
 261                         dprintk_pte("   %02d: 0x%x - 0x%x (0x%llx)\n",
 262                                     i, pteg[i], pteg[i+1], ptem);
 263                 }
 264         }
 265
 266         return -ENOENT;
 267 }
 268
 269 static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 270                                       struct kvmppc_pte *pte, bool data)
 271 {
 272         int r;
 273
 274         pte->eaddr = eaddr;
 275         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data);
 276         if (r < 0)
 277                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, true);
 278         if (r < 0)
 279                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, false);
 280
 281         return r;
 282 }
 283
 284
 285 static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 286 {
 287         return to_book3s(vcpu)->sr[srnum].raw;
 288 }
 289
 290 static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
 291                                         ulong value)
 292 {
 293         struct kvmppc_sr *sre;
 294
 295         sre = &to_book3s(vcpu)->sr[srnum];
 296
 297         /* Flush any left-over shadows from the previous SR */
 298
 299         /* XXX Not necessary? */
 300         /* kvmppc_mmu_pte_flush(vcpu, ((u64)sre->vsid) << 28, 0xf0000000ULL); */
 301
 302         /* And then put in the new SR */
 303         sre->raw = value;
 304         sre->vsid = (value & 0x0fffffff);
 305         sre->Ks = (value & 0x40000000) ? true : false;
 306         sre->Kp = (value & 0x20000000) ? true : false;
 307         sre->nx = (value & 0x10000000) ? true : false;
 308
 309         /* Map the new segment */
 310         kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
 311 }
 312
 313 static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
 314 {
 315         kvmppc_mmu_pte_flush(vcpu, ea, ~0xFFFULL);
 316 }
 317
 318 static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, u64 esid,
 319                                              u64 *vsid)
 320 {
 321         /* In case we only have one of MSR_IR or MSR_DR set, let's put
 322            that in the real-mode context (and hope RM doesn't access
 323            high memory) */
 324         switch (vcpu->arch.msr & (MSR_DR|MSR_IR)) {
 325         case 0:
 326                 *vsid = (VSID_REAL >> 16) | esid;
 327                 break;
 328         case MSR_IR:
 329                 *vsid = (VSID_REAL_IR >> 16) | esid;
 330                 break;
 331         case MSR_DR:
 332                 *vsid = (VSID_REAL_DR >> 16) | esid;
 333                 break;
 334         case MSR_DR|MSR_IR:
 335         {
 336                 ulong ea;
 337                 ea = esid << SID_SHIFT;
 338                 *vsid = find_sr(to_book3s(vcpu), ea)->vsid;
 339                 break;
 340         }
 341         default:
 342                 BUG();
 343         }
 344
 345         return 0;
 346 }
 347
 348 static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 349 {
 350         return true;
 351 }
 352
 353
 354 void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
 355 {
 356         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 357
 358         mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
 359         mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
 360         mmu->xlate = kvmppc_mmu_book3s_32_xlate;
 361         mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
 362         mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
 363         mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
 364         mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
 365         mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
 366
 367         mmu->slbmte = NULL;
 368         mmu->slbmfee = NULL;
 369         mmu->slbmfev = NULL;
 370         mmu->slbie = NULL;
 371         mmu->slbia = NULL;
 372 }