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 #include "exec/exec-all.h"
  25
  26
  27 void cpu_sync_bndcs_hflags(CPUX86State *env)
  28 {
  29     uint32_t hflags = env->hflags;
  30     uint32_t hflags2 = env->hflags2;
  31     uint32_t bndcsr;
  32
  33     if ((hflags & HF_CPL_MASK) == 3) {
  34         bndcsr = env->bndcs_regs.cfgu;
  35     } else {
  36         bndcsr = env->msr_bndcfgs;
  37     }
  38
  39     if ((env->cr[4] & CR4_OSXSAVE_MASK)
  40         && (env->xcr0 & XSTATE_BNDCSR_MASK)
  41         && (bndcsr & BNDCFG_ENABLE)) {
  42         hflags |= HF_MPX_EN_MASK;
  43     } else {
  44         hflags &= ~HF_MPX_EN_MASK;
  45     }
  46
  47     if (bndcsr & BNDCFG_BNDPRESERVE) {
  48         hflags2 |= HF2_MPX_PR_MASK;
  49     } else {
  50         hflags2 &= ~HF2_MPX_PR_MASK;
  51     }
  52
  53     env->hflags = hflags;
  54     env->hflags2 = hflags2;
  55 }
  56
  57 void helper_bndck(CPUX86State *env, uint32_t fail)
  58 {
  59     if (unlikely(fail)) {
  60         env->bndcs_regs.sts = 1;
  61         raise_exception_ra(env, EXCP05_BOUND, GETPC());
  62     }
  63 }
  64
  65 static uint64_t lookup_bte64(CPUX86State *env, uint64_t base, uintptr_t ra)
  66 {
  67     uint64_t bndcsr, bde, bt;
  68
  69     if ((env->hflags & HF_CPL_MASK) == 3) {
  70         bndcsr = env->bndcs_regs.cfgu;
  71     } else {
  72         bndcsr = env->msr_bndcfgs;
  73     }
  74
  75     bde = (extract64(base, 20, 28) << 3) + (extract64(bndcsr, 20, 44) << 12);
  76     bt = cpu_ldq_data_ra(env, bde, ra);
  77     if ((bt & 1) == 0) {
  78         env->bndcs_regs.sts = bde | 2;
  79         raise_exception_ra(env, EXCP05_BOUND, ra);
  80     }
  81
  82     return (extract64(base, 3, 17) << 5) + (bt & ~7);
  83 }
  84
  85 static uint32_t lookup_bte32(CPUX86State *env, uint32_t base, uintptr_t ra)
  86 {
  87     uint32_t bndcsr, bde, bt;
  88
  89     if ((env->hflags & HF_CPL_MASK) == 3) {
  90         bndcsr = env->bndcs_regs.cfgu;
  91     } else {
  92         bndcsr = env->msr_bndcfgs;
  93     }
  94
  95     bde = (extract32(base, 12, 20) << 2) + (bndcsr & TARGET_PAGE_MASK);
  96     bt = cpu_ldl_data_ra(env, bde, ra);
  97     if ((bt & 1) == 0) {
  98         env->bndcs_regs.sts = bde | 2;
  99         raise_exception_ra(env, EXCP05_BOUND, ra);
 100     }
 101
 102     return (extract32(base, 2, 10) << 4) + (bt & ~3);
 103 }
 104
 105 uint64_t helper_bndldx64(CPUX86State *env, target_ulong base, target_ulong ptr)
 106 {
 107     uintptr_t ra = GETPC();
 108     uint64_t bte, lb, ub, pt;
 109
 110     bte = lookup_bte64(env, base, ra);
 111     lb = cpu_ldq_data_ra(env, bte, ra);
 112     ub = cpu_ldq_data_ra(env, bte + 8, ra);
 113     pt = cpu_ldq_data_ra(env, bte + 16, ra);
 114
 115     if (pt != ptr) {
 116         lb = ub = 0;
 117     }
 118     env->mmx_t0.MMX_Q(0) = ub;
 119     return lb;
 120 }
 121
 122 uint64_t helper_bndldx32(CPUX86State *env, target_ulong base, target_ulong ptr)
 123 {
 124     uintptr_t ra = GETPC();
 125     uint32_t bte, lb, ub, pt;
 126
 127     bte = lookup_bte32(env, base, ra);
 128     lb = cpu_ldl_data_ra(env, bte, ra);
 129     ub = cpu_ldl_data_ra(env, bte + 4, ra);
 130     pt = cpu_ldl_data_ra(env, bte + 8, ra);
 131
 132     if (pt != ptr) {
 133         lb = ub = 0;
 134     }
 135     return ((uint64_t)ub << 32) | lb;
 136 }
 137
 138 void helper_bndstx64(CPUX86State *env, target_ulong base, target_ulong ptr,
 139                      uint64_t lb, uint64_t ub)
 140 {
 141     uintptr_t ra = GETPC();
 142     uint64_t bte;
 143
 144     bte = lookup_bte64(env, base, ra);
 145     cpu_stq_data_ra(env, bte, lb, ra);
 146     cpu_stq_data_ra(env, bte + 8, ub, ra);
 147     cpu_stq_data_ra(env, bte + 16, ptr, ra);
 148 }
 149
 150 void helper_bndstx32(CPUX86State *env, target_ulong base, target_ulong ptr,
 151                      uint64_t lb, uint64_t ub)
 152 {
 153     uintptr_t ra = GETPC();
 154     uint32_t bte;
 155
 156     bte = lookup_bte32(env, base, ra);
 157     cpu_stl_data_ra(env, bte, lb, ra);
 158     cpu_stl_data_ra(env, bte + 4, ub, ra);
 159     cpu_stl_data_ra(env, bte + 8, ptr, ra);
 160 }
 161
 162 void helper_bnd_jmp(CPUX86State *env)
 163 {
 164     if (!(env->hflags2 & HF2_MPX_PR_MASK)) {
 165         memset(env->bnd_regs, 0, sizeof(env->bnd_regs));
 166         env->hflags &= ~HF_MPX_IU_MASK;
 167     }
 168 }