xref: /openbmc/qemu/target/i386/tcg/mpx_helper.c (revision f0984d40)
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 "exec/cpu_ldst.h"
24 #include "exec/exec-all.h"
25 #include "helper-tcg.h"
26 
27 
28 void helper_bndck(CPUX86State *env, uint32_t fail)
29 {
30     if (unlikely(fail)) {
31         env->bndcs_regs.sts = 1;
32         raise_exception_ra(env, EXCP05_BOUND, GETPC());
33     }
34 }
35 
36 static uint64_t lookup_bte64(CPUX86State *env, uint64_t base, uintptr_t ra)
37 {
38     uint64_t bndcsr, bde, bt;
39 
40     if ((env->hflags & HF_CPL_MASK) == 3) {
41         bndcsr = env->bndcs_regs.cfgu;
42     } else {
43         bndcsr = env->msr_bndcfgs;
44     }
45 
46     bde = (extract64(base, 20, 28) << 3) + (extract64(bndcsr, 20, 44) << 12);
47     bt = cpu_ldq_data_ra(env, bde, ra);
48     if ((bt & 1) == 0) {
49         env->bndcs_regs.sts = bde | 2;
50         raise_exception_ra(env, EXCP05_BOUND, ra);
51     }
52 
53     return (extract64(base, 3, 17) << 5) + (bt & ~7);
54 }
55 
56 static uint32_t lookup_bte32(CPUX86State *env, uint32_t base, uintptr_t ra)
57 {
58     uint32_t bndcsr, bde, bt;
59 
60     if ((env->hflags & HF_CPL_MASK) == 3) {
61         bndcsr = env->bndcs_regs.cfgu;
62     } else {
63         bndcsr = env->msr_bndcfgs;
64     }
65 
66     bde = (extract32(base, 12, 20) << 2) + (bndcsr & TARGET_PAGE_MASK);
67     bt = cpu_ldl_data_ra(env, bde, ra);
68     if ((bt & 1) == 0) {
69         env->bndcs_regs.sts = bde | 2;
70         raise_exception_ra(env, EXCP05_BOUND, ra);
71     }
72 
73     return (extract32(base, 2, 10) << 4) + (bt & ~3);
74 }
75 
76 uint64_t helper_bndldx64(CPUX86State *env, target_ulong base, target_ulong ptr)
77 {
78     uintptr_t ra = GETPC();
79     uint64_t bte, lb, ub, pt;
80 
81     bte = lookup_bte64(env, base, ra);
82     lb = cpu_ldq_data_ra(env, bte, ra);
83     ub = cpu_ldq_data_ra(env, bte + 8, ra);
84     pt = cpu_ldq_data_ra(env, bte + 16, ra);
85 
86     if (pt != ptr) {
87         lb = ub = 0;
88     }
89     env->mmx_t0.MMX_Q(0) = ub;
90     return lb;
91 }
92 
93 uint64_t helper_bndldx32(CPUX86State *env, target_ulong base, target_ulong ptr)
94 {
95     uintptr_t ra = GETPC();
96     uint32_t bte, lb, ub, pt;
97 
98     bte = lookup_bte32(env, base, ra);
99     lb = cpu_ldl_data_ra(env, bte, ra);
100     ub = cpu_ldl_data_ra(env, bte + 4, ra);
101     pt = cpu_ldl_data_ra(env, bte + 8, ra);
102 
103     if (pt != ptr) {
104         lb = ub = 0;
105     }
106     return ((uint64_t)ub << 32) | lb;
107 }
108 
109 void helper_bndstx64(CPUX86State *env, target_ulong base, target_ulong ptr,
110                      uint64_t lb, uint64_t ub)
111 {
112     uintptr_t ra = GETPC();
113     uint64_t bte;
114 
115     bte = lookup_bte64(env, base, ra);
116     cpu_stq_data_ra(env, bte, lb, ra);
117     cpu_stq_data_ra(env, bte + 8, ub, ra);
118     cpu_stq_data_ra(env, bte + 16, ptr, ra);
119 }
120 
121 void helper_bndstx32(CPUX86State *env, target_ulong base, target_ulong ptr,
122                      uint64_t lb, uint64_t ub)
123 {
124     uintptr_t ra = GETPC();
125     uint32_t bte;
126 
127     bte = lookup_bte32(env, base, ra);
128     cpu_stl_data_ra(env, bte, lb, ra);
129     cpu_stl_data_ra(env, bte + 4, ub, ra);
130     cpu_stl_data_ra(env, bte + 8, ptr, ra);
131 }
132 
133 void helper_bnd_jmp(CPUX86State *env)
134 {
135     if (!(env->hflags2 & HF2_MPX_PR_MASK)) {
136         memset(env->bnd_regs, 0, sizeof(env->bnd_regs));
137         env->hflags &= ~HF_MPX_IU_MASK;
138     }
139 }
140