1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
ATOMICDIR=$(dirname $0)
. ${ATOMICDIR}/atomic-tbl.sh
#gen_param_check(meta, arg)
gen_param_check()
{
local meta="$1"; shift
local arg="$1"; shift
local type="${arg%%:*}"
local name="$(gen_param_name "${arg}")"
local rw="write"
case "${type#c}" in
i) return;;
esac
if [ ${type#c} != ${type} ]; then
# We don't write to constant parameters.
rw="read"
elif [ "${meta}" != "s" ]; then
# An atomic RMW: if this parameter is not a constant, and this atomic is
# not just a 's'tore, this parameter is both read from and written to.
rw="read_write"
fi
printf "\tinstrument_atomic_${rw}(${name}, sizeof(*${name}));\n"
}
#gen_params_checks(meta, arg...)
gen_params_checks()
{
local meta="$1"; shift
local order="$1"; shift
if [ "${order}" = "_release" ]; then
printf "\tkcsan_release();\n"
elif [ -z "${order}" ] && ! meta_in "$meta" "slv"; then
# RMW with return value is fully ordered
printf "\tkcsan_mb();\n"
fi
while [ "$#" -gt 0 ]; do
gen_param_check "$meta" "$1"
shift;
done
}
#gen_proto_order_variant(meta, pfx, name, sfx, order, atomic, int, arg...)
gen_proto_order_variant()
{
local meta="$1"; shift
local pfx="$1"; shift
local name="$1"; shift
local sfx="$1"; shift
local order="$1"; shift
local atomic="$1"; shift
local int="$1"; shift
local atomicname="${atomic}_${pfx}${name}${sfx}${order}"
local ret="$(gen_ret_type "${meta}" "${int}")"
local params="$(gen_params "${int}" "${atomic}" "$@")"
local checks="$(gen_params_checks "${meta}" "${order}" "$@")"
local args="$(gen_args "$@")"
local retstmt="$(gen_ret_stmt "${meta}")"
cat <<EOF
static __always_inline ${ret}
${atomicname}(${params})
{
${checks}
${retstmt}arch_${atomicname}(${args});
}
EOF
printf "\n"
}
gen_xchg()
{
local xchg="$1"; shift
local order="$1"; shift
local mult="$1"; shift
kcsan_barrier=""
if [ "${xchg%_local}" = "${xchg}" ]; then
case "$order" in
_release) kcsan_barrier="kcsan_release()" ;;
"") kcsan_barrier="kcsan_mb()" ;;
esac
fi
if [ "${xchg%${xchg#try_cmpxchg}}" = "try_cmpxchg" ] ; then
cat <<EOF
#define ${xchg}${order}(ptr, oldp, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
typeof(oldp) __ai_oldp = (oldp); \\
EOF
[ -n "$kcsan_barrier" ] && printf "\t${kcsan_barrier}; \\\\\n"
cat <<EOF
instrument_atomic_read_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
instrument_read_write(__ai_oldp, ${mult}sizeof(*__ai_oldp)); \\
arch_${xchg}${order}(__ai_ptr, __ai_oldp, __VA_ARGS__); \\
})
EOF
else
cat <<EOF
#define ${xchg}${order}(ptr, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
EOF
[ -n "$kcsan_barrier" ] && printf "\t${kcsan_barrier}; \\\\\n"
cat <<EOF
instrument_atomic_read_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
arch_${xchg}${order}(__ai_ptr, __VA_ARGS__); \\
})
EOF
fi
}
cat << EOF
// SPDX-License-Identifier: GPL-2.0
// Generated by $0
// DO NOT MODIFY THIS FILE DIRECTLY
/*
* This file provides wrappers with KASAN instrumentation for atomic operations.
* To use this functionality an arch's atomic.h file needs to define all
* atomic operations with arch_ prefix (e.g. arch_atomic_read()) and include
* this file at the end. This file provides atomic_read() that forwards to
* arch_atomic_read() for actual atomic operation.
* Note: if an arch atomic operation is implemented by means of other atomic
* operations (e.g. atomic_read()/atomic_cmpxchg() loop), then it needs to use
* arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
* double instrumentation.
*/
#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
#define _LINUX_ATOMIC_INSTRUMENTED_H
#include <linux/build_bug.h>
#include <linux/compiler.h>
#include <linux/instrumented.h>
EOF
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic" "int" ${args}
done
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
done
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic_long" "long" ${args}
done
for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg" "try_cmpxchg64"; do
for order in "" "_acquire" "_release" "_relaxed"; do
gen_xchg "${xchg}" "${order}" ""
printf "\n"
done
done
for xchg in "cmpxchg_local" "cmpxchg64_local" "sync_cmpxchg" "try_cmpxchg_local" "try_cmpxchg64_local" ; do
gen_xchg "${xchg}" "" ""
printf "\n"
done
gen_xchg "cmpxchg_double" "" "2 * "
printf "\n\n"
gen_xchg "cmpxchg_double_local" "" "2 * "
cat <<EOF
#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
EOF
|
