1
2 /*--------------------------------------------------------------------*/
3 /*--- Notional "implementation" for m_vki. ---*/
4 /*--- m_vki.c ---*/
5 /*--------------------------------------------------------------------*/
6
7 /*
8 This file is part of Valgrind, a dynamic binary instrumentation
9 framework.
10
11 Copyright (C) 2006-2017 OpenWorks LLP
12 info@open-works.co.uk
13
14 This program is free software; you can redistribute it and/or
15 modify it under the terms of the GNU General Public License as
16 published by the Free Software Foundation; either version 2 of the
17 License, or (at your option) any later version.
18
19 This program is distributed in the hope that it will be useful, but
20 WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 General Public License for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with this program; if not, write to the Free Software
26 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
27 02111-1307, USA.
28
29 The GNU General Public License is contained in the file COPYING.
30 */
31
32 #include "pub_core_basics.h"
33 #include "pub_core_libcassert.h"
34 #include "pub_core_vki.h" /* self */
35
36 /* We have pub_{core,tool}_vki.h. This is the matching implementation
37 for that interface. In fact there is no implementation, as the
38 sole purpose of the module is to export types and constants
39 describing the kernel interface, so this file is nearly empty. */
40
41
42 /* ppc32/64, arm64 and mips32/64 (linux) determine page size at startup,
43 hence m_vki is the logical place to store that info. */
44
45 #if defined(VGP_ppc32_linux) || defined(VGP_ppc64be_linux) \
46 || defined(VGP_ppc64le_linux) || defined(VGP_arm64_linux) \
47 || defined(VGP_mips32_linux) || defined(VGP_mips64_linux)
48 unsigned long VKI_PAGE_SHIFT = 12;
49 unsigned long VKI_PAGE_SIZE = 1UL << 12;
50 #endif
51
52
53 /* Do initial consistency checks on some of the definitions to do with
54 signals (vki_sigset_t and vki_sigaction_{toK,fromK}_t). This stuff
55 is fragile enough that it's important to check at startup that
56 the world looks like what we expect it to look like.
57
58 The most important thing is to check that the definition of signal
59 sets for this platform is right. A signal set consists of some
60 number _VKI_NSIG_WORDS of 32- or 64-bit words. Because the kernel
61 itself has some indexing scheme to set/clear individual bits in the
62 set, we must make sure we use the same layout/scheme: where this
63 requirement bites us is in the VG_(sigfillset) etc functions in
64 m_libcsignal.c. So we check carefully here that it's all sensible.
65 */
VG_(vki_do_initial_consistency_checks)66 void VG_(vki_do_initial_consistency_checks) ( void )
67 {
68 /* --- Platform-independent checks on signal sets --- */
69
70 vki_sigset_t set;
71 // Set's size must agree with _VKI_NSIG
72 vg_assert( 8 * sizeof(set) == _VKI_NSIG );
73 // Set's word size must agree with _VKI_NSIG_BPW
74 vg_assert( 8 * sizeof(set.sig[0]) == _VKI_NSIG_BPW );
75 // The set elements are 32- or 64-bit
76 vg_assert( _VKI_NSIG_BPW == 32 || _VKI_NSIG_BPW == 64 );
77
78 /* --- Platform-specific checks on signal sets --- */
79
80 # if defined(VGO_linux) || defined(VGO_solaris)
81 /* nothing to check */
82 # elif defined(VGP_x86_darwin) || defined(VGP_amd64_darwin)
83 vg_assert(_VKI_NSIG == NSIG);
84 vg_assert(_VKI_NSIG == 32);
85 vg_assert(_VKI_NSIG_WORDS == 1);
86 vg_assert(sizeof(sigset_t) /* defined by Darwin */
87 == sizeof(vki_sigset_t) /* what we actually use */);
88 # else
89 # error "Unknown plat"
90 # endif
91
92 /* --- Platform-specific checks on sigactions --- */
93
94 # if defined(VGO_linux)
95 /* the toK- and fromK- forms are identical */
96 vg_assert( sizeof(vki_sigaction_toK_t)
97 == sizeof(vki_sigaction_fromK_t) );
98 # elif defined(VGO_darwin)
99 /* the toK- and fromK- forms differ by one function-pointer field
100 (sa_tramp) */
101 vg_assert( sizeof(vki_sigaction_toK_t)
102 == sizeof(vki_sigaction_fromK_t) + sizeof(void*) );
103
104 vg_assert(sizeof(struct sigaction) == sizeof(vki_sigaction_fromK_t));
105 vg_assert(sizeof(struct __sigaction) == sizeof(vki_sigaction_toK_t));
106 { struct __sigaction t1;
107 vki_sigaction_toK_t t2;
108 struct sigaction f1;
109 vki_sigaction_fromK_t f2;
110 vg_assert(sizeof(t1.sa_handler) == sizeof(t2.ksa_handler));
111 vg_assert(sizeof(t1.sa_tramp) == sizeof(t2.sa_tramp));
112 vg_assert(sizeof(t1.sa_mask) == sizeof(t2.sa_mask));
113 vg_assert(sizeof(t1.sa_flags) == sizeof(t2.sa_flags));
114 vg_assert(sizeof(f1.sa_handler) == sizeof(f2.ksa_handler));
115 vg_assert(sizeof(f1.sa_mask) == sizeof(f2.sa_mask));
116 vg_assert(sizeof(f1.sa_flags) == sizeof(f2.sa_flags));
117 # if 0
118 vg_assert(offsetof(t1,sa_handler) == offsetof(t2.ksa_handler));
119 vg_assert(offsetof(t1.sa_tramp) == offsetof(t2.sa_tramp));
120 vg_assert(offsetof(t1.sa_mask) == offsetof(t2.sa_mask));
121 vg_assert(offsetof(t1.sa_flags) == offsetof(t2.sa_flags));
122 vg_assert(offsetof(f1.sa_handler) == offsetof(f2.ksa_handler));
123 vg_assert(offsetof(f1.sa_mask) == offsetof(f2.sa_mask));
124 vg_assert(offsetof(f1.sa_flags) == offsetof(f2.sa_flags));
125 # endif
126 }
127 /* also .. */
128 /* VKI_SET_SIGMASK is hardwired into syscall-x86-darwin.S and
129 syscall-amd64-darwin.S */
130 vg_assert(VKI_SIG_SETMASK == 3);
131
132 # elif defined(VGO_solaris)
133 /* the toK- and fromK- forms are identical */
134 vg_assert(sizeof(vki_sigaction_toK_t)
135 == sizeof(vki_sigaction_fromK_t));
136 /* VKI_SET_SIGMASK is hardwired into syscall-x86-solaris.S
137 and syscall-amd64-solaris.S */
138 vg_assert(VKI_SIG_SETMASK == 3);
139
140 # else
141 # error "Unknown OS"
142 # endif
143 }
144
145
146 /*--------------------------------------------------------------------*/
147 /*--- end m_vki.c ---*/
148 /*--------------------------------------------------------------------*/
149