scripts/atomic/gen-atomic-instrumented.sh

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