xref: /qemu/target/i386/tcg/mpx_helper.c (revision bcfee4938f8d4e8bf5f49981d3c8a78cf267cb4e)
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 2.1 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 
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/helper-proto.h"
23 #include "accel/tcg/cpu-ldst.h"
24 #include "exec/exec-all.h"
25 #include "exec/target_page.h"
26 #include "helper-tcg.h"
27 
28 
29 void helper_bndck(CPUX86State *env, uint32_t fail)
30 {
31     if (unlikely(fail)) {
32         env->bndcs_regs.sts = 1;
33         raise_exception_ra(env, EXCP05_BOUND, GETPC());
34     }
35 }
36 
37 static uint64_t lookup_bte64(CPUX86State *env, uint64_t base, uintptr_t ra)
38 {
39     uint64_t bndcsr, bde, bt;
40 
41     if ((env->hflags & HF_CPL_MASK) == 3) {
42         bndcsr = env->bndcs_regs.cfgu;
43     } else {
44         bndcsr = env->msr_bndcfgs;
45     }
46 
47     bde = (extract64(base, 20, 28) << 3) + (extract64(bndcsr, 20, 44) << 12);
48     bt = cpu_ldq_data_ra(env, bde, ra);
49     if ((bt & 1) == 0) {
50         env->bndcs_regs.sts = bde | 2;
51         raise_exception_ra(env, EXCP05_BOUND, ra);
52     }
53 
54     return (extract64(base, 3, 17) << 5) + (bt & ~7);
55 }
56 
57 static uint32_t lookup_bte32(CPUX86State *env, uint32_t base, uintptr_t ra)
58 {
59     uint32_t bndcsr, bde, bt;
60 
61     if ((env->hflags & HF_CPL_MASK) == 3) {
62         bndcsr = env->bndcs_regs.cfgu;
63     } else {
64         bndcsr = env->msr_bndcfgs;
65     }
66 
67     bde = (extract32(base, 12, 20) << 2) + (bndcsr & TARGET_PAGE_MASK);
68     bt = cpu_ldl_data_ra(env, bde, ra);
69     if ((bt & 1) == 0) {
70         env->bndcs_regs.sts = bde | 2;
71         raise_exception_ra(env, EXCP05_BOUND, ra);
72     }
73 
74     return (extract32(base, 2, 10) << 4) + (bt & ~3);
75 }
76 
77 uint64_t helper_bndldx64(CPUX86State *env, target_ulong base, target_ulong ptr)
78 {
79     uintptr_t ra = GETPC();
80     uint64_t bte, lb, ub, pt;
81 
82     bte = lookup_bte64(env, base, ra);
83     lb = cpu_ldq_data_ra(env, bte, ra);
84     ub = cpu_ldq_data_ra(env, bte + 8, ra);
85     pt = cpu_ldq_data_ra(env, bte + 16, ra);
86 
87     if (pt != ptr) {
88         lb = ub = 0;
89     }
90     env->mmx_t0.MMX_Q(0) = ub;
91     return lb;
92 }
93 
94 uint64_t helper_bndldx32(CPUX86State *env, target_ulong base, target_ulong ptr)
95 {
96     uintptr_t ra = GETPC();
97     uint32_t bte, lb, ub, pt;
98 
99     bte = lookup_bte32(env, base, ra);
100     lb = cpu_ldl_data_ra(env, bte, ra);
101     ub = cpu_ldl_data_ra(env, bte + 4, ra);
102     pt = cpu_ldl_data_ra(env, bte + 8, ra);
103 
104     if (pt != ptr) {
105         lb = ub = 0;
106     }
107     return ((uint64_t)ub << 32) | lb;
108 }
109 
110 void helper_bndstx64(CPUX86State *env, target_ulong base, target_ulong ptr,
111                      uint64_t lb, uint64_t ub)
112 {
113     uintptr_t ra = GETPC();
114     uint64_t bte;
115 
116     bte = lookup_bte64(env, base, ra);
117     cpu_stq_data_ra(env, bte, lb, ra);
118     cpu_stq_data_ra(env, bte + 8, ub, ra);
119     cpu_stq_data_ra(env, bte + 16, ptr, ra);
120 }
121 
122 void helper_bndstx32(CPUX86State *env, target_ulong base, target_ulong ptr,
123                      uint64_t lb, uint64_t ub)
124 {
125     uintptr_t ra = GETPC();
126     uint32_t bte;
127 
128     bte = lookup_bte32(env, base, ra);
129     cpu_stl_data_ra(env, bte, lb, ra);
130     cpu_stl_data_ra(env, bte + 4, ub, ra);
131     cpu_stl_data_ra(env, bte + 8, ptr, ra);
132 }
133 
134 void helper_bnd_jmp(CPUX86State *env)
135 {
136     if (!(env->hflags2 & HF2_MPX_PR_MASK)) {
137         memset(env->bnd_regs, 0, sizeof(env->bnd_regs));
138         env->hflags &= ~HF_MPX_IU_MASK;
139     }
140 }
141