cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

physaddr.c (9696B)


      1/*
      2 * MIPS TLB (Translation lookaside buffer) helpers.
      3 *
      4 *  Copyright (c) 2004-2005 Jocelyn Mayer
      5 *
      6 * This library is free software; you can redistribute it and/or
      7 * modify it under the terms of the GNU Lesser General Public
      8 * License as published by the Free Software Foundation; either
      9 * version 2.1 of the License, or (at your option) any later version.
     10 *
     11 * This library is distributed in the hope that it will be useful,
     12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14 * Lesser General Public License for more details.
     15 *
     16 * You should have received a copy of the GNU Lesser General Public
     17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
     18 */
     19#include "qemu/osdep.h"
     20#include "cpu.h"
     21#include "exec/exec-all.h"
     22#include "../internal.h"
     23
     24static int is_seg_am_mapped(unsigned int am, bool eu, int mmu_idx)
     25{
     26    /*
     27     * Interpret access control mode and mmu_idx.
     28     *           AdE?     TLB?
     29     *      AM  K S U E  K S U E
     30     * UK    0  0 1 1 0  0 - - 0
     31     * MK    1  0 1 1 0  1 - - !eu
     32     * MSK   2  0 0 1 0  1 1 - !eu
     33     * MUSK  3  0 0 0 0  1 1 1 !eu
     34     * MUSUK 4  0 0 0 0  0 1 1 0
     35     * USK   5  0 0 1 0  0 0 - 0
     36     * -     6  - - - -  - - - -
     37     * UUSK  7  0 0 0 0  0 0 0 0
     38     */
     39    int32_t adetlb_mask;
     40
     41    switch (mmu_idx) {
     42    case 3: /* ERL */
     43        /* If EU is set, always unmapped */
     44        if (eu) {
     45            return 0;
     46        }
     47        /* fall through */
     48    case MIPS_HFLAG_KM:
     49        /* Never AdE, TLB mapped if AM={1,2,3} */
     50        adetlb_mask = 0x70000000;
     51        goto check_tlb;
     52
     53    case MIPS_HFLAG_SM:
     54        /* AdE if AM={0,1}, TLB mapped if AM={2,3,4} */
     55        adetlb_mask = 0xc0380000;
     56        goto check_ade;
     57
     58    case MIPS_HFLAG_UM:
     59        /* AdE if AM={0,1,2,5}, TLB mapped if AM={3,4} */
     60        adetlb_mask = 0xe4180000;
     61        /* fall through */
     62    check_ade:
     63        /* does this AM cause AdE in current execution mode */
     64        if ((adetlb_mask << am) < 0) {
     65            return TLBRET_BADADDR;
     66        }
     67        adetlb_mask <<= 8;
     68        /* fall through */
     69    check_tlb:
     70        /* is this AM mapped in current execution mode */
     71        return ((adetlb_mask << am) < 0);
     72    default:
     73        assert(0);
     74        return TLBRET_BADADDR;
     75    };
     76}
     77
     78static int get_seg_physical_address(CPUMIPSState *env, hwaddr *physical,
     79                                    int *prot, target_ulong real_address,
     80                                    MMUAccessType access_type, int mmu_idx,
     81                                    unsigned int am, bool eu,
     82                                    target_ulong segmask,
     83                                    hwaddr physical_base)
     84{
     85    int mapped = is_seg_am_mapped(am, eu, mmu_idx);
     86
     87    if (mapped < 0) {
     88        /* is_seg_am_mapped can report TLBRET_BADADDR */
     89        return mapped;
     90    } else if (mapped) {
     91        /* The segment is TLB mapped */
     92        return env->tlb->map_address(env, physical, prot, real_address,
     93                                     access_type);
     94    } else {
     95        /* The segment is unmapped */
     96        *physical = physical_base | (real_address & segmask);
     97        *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
     98        return TLBRET_MATCH;
     99    }
    100}
    101
    102static int get_segctl_physical_address(CPUMIPSState *env, hwaddr *physical,
    103                                       int *prot, target_ulong real_address,
    104                                       MMUAccessType access_type, int mmu_idx,
    105                                       uint16_t segctl, target_ulong segmask)
    106{
    107    unsigned int am = (segctl & CP0SC_AM_MASK) >> CP0SC_AM;
    108    bool eu = (segctl >> CP0SC_EU) & 1;
    109    hwaddr pa = ((hwaddr)segctl & CP0SC_PA_MASK) << 20;
    110
    111    return get_seg_physical_address(env, physical, prot, real_address,
    112                                    access_type, mmu_idx, am, eu, segmask,
    113                                    pa & ~(hwaddr)segmask);
    114}
    115
    116int get_physical_address(CPUMIPSState *env, hwaddr *physical,
    117                         int *prot, target_ulong real_address,
    118                         MMUAccessType access_type, int mmu_idx)
    119{
    120    /* User mode can only access useg/xuseg */
    121#if defined(TARGET_MIPS64)
    122    int user_mode = mmu_idx == MIPS_HFLAG_UM;
    123    int supervisor_mode = mmu_idx == MIPS_HFLAG_SM;
    124    int kernel_mode = !user_mode && !supervisor_mode;
    125    int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
    126    int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
    127    int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
    128#endif
    129    int ret = TLBRET_MATCH;
    130    /* effective address (modified for KVM T&E kernel segments) */
    131    target_ulong address = real_address;
    132
    133    if (mips_um_ksegs_enabled()) {
    134        /* KVM T&E adds guest kernel segments in useg */
    135        if (real_address >= KVM_KSEG0_BASE) {
    136            if (real_address < KVM_KSEG2_BASE) {
    137                /* kseg0 */
    138                address += KSEG0_BASE - KVM_KSEG0_BASE;
    139            } else if (real_address <= USEG_LIMIT) {
    140                /* kseg2/3 */
    141                address += KSEG2_BASE - KVM_KSEG2_BASE;
    142            }
    143        }
    144    }
    145
    146    if (address <= USEG_LIMIT) {
    147        /* useg */
    148        uint16_t segctl;
    149
    150        if (address >= 0x40000000UL) {
    151            segctl = env->CP0_SegCtl2;
    152        } else {
    153            segctl = env->CP0_SegCtl2 >> 16;
    154        }
    155        ret = get_segctl_physical_address(env, physical, prot,
    156                                          real_address, access_type,
    157                                          mmu_idx, segctl, 0x3FFFFFFF);
    158#if defined(TARGET_MIPS64)
    159    } else if (address < 0x4000000000000000ULL) {
    160        /* xuseg */
    161        if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) {
    162            ret = env->tlb->map_address(env, physical, prot,
    163                                        real_address, access_type);
    164        } else {
    165            ret = TLBRET_BADADDR;
    166        }
    167    } else if (address < 0x8000000000000000ULL) {
    168        /* xsseg */
    169        if ((supervisor_mode || kernel_mode) &&
    170            SX && address <= (0x7FFFFFFFFFFFFFFFULL & env->SEGMask)) {
    171            ret = env->tlb->map_address(env, physical, prot,
    172                                        real_address, access_type);
    173        } else {
    174            ret = TLBRET_BADADDR;
    175        }
    176    } else if (address < 0xC000000000000000ULL) {
    177        /* xkphys */
    178        if ((address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
    179            /* KX/SX/UX bit to check for each xkphys EVA access mode */
    180            static const uint8_t am_ksux[8] = {
    181                [CP0SC_AM_UK]    = (1u << CP0St_KX),
    182                [CP0SC_AM_MK]    = (1u << CP0St_KX),
    183                [CP0SC_AM_MSK]   = (1u << CP0St_SX),
    184                [CP0SC_AM_MUSK]  = (1u << CP0St_UX),
    185                [CP0SC_AM_MUSUK] = (1u << CP0St_UX),
    186                [CP0SC_AM_USK]   = (1u << CP0St_SX),
    187                [6]              = (1u << CP0St_KX),
    188                [CP0SC_AM_UUSK]  = (1u << CP0St_UX),
    189            };
    190            unsigned int am = CP0SC_AM_UK;
    191            unsigned int xr = (env->CP0_SegCtl2 & CP0SC2_XR_MASK) >> CP0SC2_XR;
    192
    193            if (xr & (1 << ((address >> 59) & 0x7))) {
    194                am = (env->CP0_SegCtl1 & CP0SC1_XAM_MASK) >> CP0SC1_XAM;
    195            }
    196            /* Does CP0_Status.KX/SX/UX permit the access mode (am) */
    197            if (env->CP0_Status & am_ksux[am]) {
    198                ret = get_seg_physical_address(env, physical, prot,
    199                                               real_address, access_type,
    200                                               mmu_idx, am, false, env->PAMask,
    201                                               0);
    202            } else {
    203                ret = TLBRET_BADADDR;
    204            }
    205        } else {
    206            ret = TLBRET_BADADDR;
    207        }
    208    } else if (address < 0xFFFFFFFF80000000ULL) {
    209        /* xkseg */
    210        if (kernel_mode && KX &&
    211            address <= (0xFFFFFFFF7FFFFFFFULL & env->SEGMask)) {
    212            ret = env->tlb->map_address(env, physical, prot,
    213                                        real_address, access_type);
    214        } else {
    215            ret = TLBRET_BADADDR;
    216        }
    217#endif
    218    } else if (address < KSEG1_BASE) {
    219        /* kseg0 */
    220        ret = get_segctl_physical_address(env, physical, prot, real_address,
    221                                          access_type, mmu_idx,
    222                                          env->CP0_SegCtl1 >> 16, 0x1FFFFFFF);
    223    } else if (address < KSEG2_BASE) {
    224        /* kseg1 */
    225        ret = get_segctl_physical_address(env, physical, prot, real_address,
    226                                          access_type, mmu_idx,
    227                                          env->CP0_SegCtl1, 0x1FFFFFFF);
    228    } else if (address < KSEG3_BASE) {
    229        /* sseg (kseg2) */
    230        ret = get_segctl_physical_address(env, physical, prot, real_address,
    231                                          access_type, mmu_idx,
    232                                          env->CP0_SegCtl0 >> 16, 0x1FFFFFFF);
    233    } else {
    234        /*
    235         * kseg3
    236         * XXX: debug segment is not emulated
    237         */
    238        ret = get_segctl_physical_address(env, physical, prot, real_address,
    239                                          access_type, mmu_idx,
    240                                          env->CP0_SegCtl0, 0x1FFFFFFF);
    241    }
    242    return ret;
    243}
    244
    245hwaddr mips_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
    246{
    247    MIPSCPU *cpu = MIPS_CPU(cs);
    248    CPUMIPSState *env = &cpu->env;
    249    hwaddr phys_addr;
    250    int prot;
    251
    252    if (get_physical_address(env, &phys_addr, &prot, addr, MMU_DATA_LOAD,
    253                             cpu_mmu_index(env, false)) != 0) {
    254        return -1;
    255    }
    256    return phys_addr;
    257}