target-i386/mpx_helper.c

   1 /*
   2  *  x86 MPX helpers
   3  *
   4  *  Copyright (c) 2015 Red Hat, Inc.
   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 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
  20 #include "qemu/osdep.h"
  21 #include "cpu.h"
  22 #include "exec/helper-proto.h"
  23 #include "exec/cpu_ldst.h"
  24
  25
  26 void cpu_sync_bndcs_hflags(CPUX86State *env)
  27 {
  28     uint32_t hflags = env->hflags;
  29     uint32_t hflags2 = env->hflags2;
  30     uint32_t bndcsr;
  31
  32     if ((hflags & HF_CPL_MASK) == 3) {
  33         bndcsr = env->bndcs_regs.cfgu;
  34     } else {
  35         bndcsr = env->msr_bndcfgs;
  36     }
  37
  38     if ((env->cr[4] & CR4_OSXSAVE_MASK)
  39         && (env->xcr0 & XSTATE_BNDCSR_MASK)
  40         && (bndcsr & BNDCFG_ENABLE)) {
  41         hflags |= HF_MPX_EN_MASK;
  42     } else {
  43         hflags &= ~HF_MPX_EN_MASK;
  44     }
  45
  46     if (bndcsr & BNDCFG_BNDPRESERVE) {
  47         hflags2 |= HF2_MPX_PR_MASK;
  48     } else {
  49         hflags2 &= ~HF2_MPX_PR_MASK;
  50     }
  51
  52     env->hflags = hflags;
  53     env->hflags2 = hflags2;
  54 }
  55
  56 void helper_bndck(CPUX86State *env, uint32_t fail)
  57 {
  58     if (unlikely(fail)) {
  59         env->bndcs_regs.sts = 1;
  60         raise_exception_ra(env, EXCP05_BOUND, GETPC());
  61     }
  62 }
  63
  64 static uint64_t lookup_bte64(CPUX86State *env, uint64_t base, uintptr_t ra)
  65 {
  66     uint64_t bndcsr, bde, bt;
  67
  68     if ((env->hflags & HF_CPL_MASK) == 3) {
  69         bndcsr = env->bndcs_regs.cfgu;
  70     } else {
  71         bndcsr = env->msr_bndcfgs;
  72     }
  73
  74     bde = (extract64(base, 20, 28) << 3) + (extract64(bndcsr, 20, 44) << 12);
  75     bt = cpu_ldq_data_ra(env, bde, ra);
  76     if ((bt & 1) == 0) {
  77         env->bndcs_regs.sts = bde | 2;
  78         raise_exception_ra(env, EXCP05_BOUND, ra);
  79     }
  80
  81     return (extract64(base, 3, 17) << 5) + (bt & ~7);
  82 }
  83
  84 static uint32_t lookup_bte32(CPUX86State *env, uint32_t base, uintptr_t ra)
  85 {
  86     uint32_t bndcsr, bde, bt;
  87
  88     if ((env->hflags & HF_CPL_MASK) == 3) {
  89         bndcsr = env->bndcs_regs.cfgu;
  90     } else {
  91         bndcsr = env->msr_bndcfgs;
  92     }
  93
  94     bde = (extract32(base, 12, 20) << 2) + (bndcsr & TARGET_PAGE_MASK);
  95     bt = cpu_ldl_data_ra(env, bde, ra);
  96     if ((bt & 1) == 0) {
  97         env->bndcs_regs.sts = bde | 2;
  98         raise_exception_ra(env, EXCP05_BOUND, ra);
  99     }
 100
 101     return (extract32(base, 2, 10) << 4) + (bt & ~3);
 102 }
 103
 104 uint64_t helper_bndldx64(CPUX86State *env, target_ulong base, target_ulong ptr)
 105 {
 106     uintptr_t ra = GETPC();
 107     uint64_t bte, lb, ub, pt;
 108
 109     bte = lookup_bte64(env, base, ra);
 110     lb = cpu_ldq_data_ra(env, bte, ra);
 111     ub = cpu_ldq_data_ra(env, bte + 8, ra);
 112     pt = cpu_ldq_data_ra(env, bte + 16, ra);
 113
 114     if (pt != ptr) {
 115         lb = ub = 0;
 116     }
 117     env->mmx_t0.MMX_Q(0) = ub;
 118     return lb;
 119 }
 120
 121 uint64_t helper_bndldx32(CPUX86State *env, target_ulong base, target_ulong ptr)
 122 {
 123     uintptr_t ra = GETPC();
 124     uint32_t bte, lb, ub, pt;
 125
 126     bte = lookup_bte32(env, base, ra);
 127     lb = cpu_ldl_data_ra(env, bte, ra);
 128     ub = cpu_ldl_data_ra(env, bte + 4, ra);
 129     pt = cpu_ldl_data_ra(env, bte + 8, ra);
 130
 131     if (pt != ptr) {
 132         lb = ub = 0;
 133     }
 134     return ((uint64_t)ub << 32) | lb;
 135 }
 136
 137 void helper_bndstx64(CPUX86State *env, target_ulong base, target_ulong ptr,
 138                      uint64_t lb, uint64_t ub)
 139 {
 140     uintptr_t ra = GETPC();
 141     uint64_t bte;
 142
 143     bte = lookup_bte64(env, base, ra);
 144     cpu_stq_data_ra(env, bte, lb, ra);
 145     cpu_stq_data_ra(env, bte + 8, ub, ra);
 146     cpu_stq_data_ra(env, bte + 16, ptr, ra);
 147 }
 148
 149 void helper_bndstx32(CPUX86State *env, target_ulong base, target_ulong ptr,
 150                      uint64_t lb, uint64_t ub)
 151 {
 152     uintptr_t ra = GETPC();
 153     uint32_t bte;
 154
 155     bte = lookup_bte32(env, base, ra);
 156     cpu_stl_data_ra(env, bte, lb, ra);
 157     cpu_stl_data_ra(env, bte + 4, ub, ra);
 158     cpu_stl_data_ra(env, bte + 8, ptr, ra);
 159 }
 160
 161 void helper_bnd_jmp(CPUX86State *env)
 162 {
 163     if (!(env->hflags2 & HF2_MPX_PR_MASK)) {
 164         memset(env->bnd_regs, 0, sizeof(env->bnd_regs));
 165         env->hflags &= ~HF_MPX_IU_MASK;
 166     }
 167 }