linux/arch/powerpc/kvm/book3s_32_mmu.c
<<
>>
Prefs
   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
  40static 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
  49static inline u32 sr_vsid(u32 sr_raw)
  50{
  51        return sr_raw & 0x0fffffff;
  52}
  53
  54static inline bool sr_valid(u32 sr_raw)
  55{
  56        return (sr_raw & 0x80000000) ? false : true;
  57}
  58
  59static inline bool sr_ks(u32 sr_raw)
  60{
  61        return (sr_raw & 0x40000000) ? true: false;
  62}
  63
  64static inline bool sr_kp(u32 sr_raw)
  65{
  66        return (sr_raw & 0x20000000) ? true: false;
  67}
  68
  69static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
  70                                          struct kvmppc_pte *pte, bool data,
  71                                          bool iswrite);
  72static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
  73                                             u64 *vsid);
  74
  75static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
  76{
  77        return kvmppc_get_sr(vcpu, (eaddr >> 28) & 0xf);
  78}
  79
  80static 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
  93static 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
 121static 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
 127static 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
 182static 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
 275no_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
 290static 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
 326static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
 327{
 328        return kvmppc_get_sr(vcpu, srnum);
 329}
 330
 331static 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
 338static 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
 348static 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
 391static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
 392{
 393        return true;
 394}
 395
 396
 397void 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}
 416