usr/src/cmd/acpi/iasl/asllookup.c

   1 /******************************************************************************
   2  *
   3  * Module Name: asllookup- Namespace lookup functions
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2016, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include "aslcompiler.h"
  45 #include "aslcompiler.y.h"
  46 #include "acparser.h"
  47 #include "amlcode.h"
  48 #include "acnamesp.h"
  49 #include "acdispat.h"
  50
  51
  52 #define _COMPONENT          ACPI_COMPILER
  53         ACPI_MODULE_NAME    ("asllookup")
  54
  55 /* Local prototypes */
  56
  57 static ACPI_STATUS
  58 LkIsObjectUsed (
  59     ACPI_HANDLE             ObjHandle,
  60     UINT32                  Level,
  61     void                    *Context,
  62     void                    **ReturnValue);
  63
  64 static ACPI_PARSE_OBJECT *
  65 LkGetNameOp (
  66     ACPI_PARSE_OBJECT       *Op);
  67
  68
  69 /*******************************************************************************
  70  *
  71  * FUNCTION:    LkFindUnreferencedObjects
  72  *
  73  * PARAMETERS:  None
  74  *
  75  * RETURN:      None
  76  *
  77  * DESCRIPTION: Namespace walk to find objects that are not referenced in any
  78  *              way. Must be called after the namespace has been cross
  79  *              referenced.
  80  *
  81  ******************************************************************************/
  82
  83 void
  84 LkFindUnreferencedObjects (
  85     void)
  86 {
  87
  88     /* Walk entire namespace from the supplied root */
  89
  90     (void) AcpiNsWalkNamespace (ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
  91                 ACPI_UINT32_MAX, FALSE, LkIsObjectUsed, NULL,
  92                 NULL, NULL);
  93 }
  94
  95
  96 /*******************************************************************************
  97  *
  98  * FUNCTION:    LkIsObjectUsed
  99  *
 100  * PARAMETERS:  ACPI_WALK_CALLBACK
 101  *
 102  * RETURN:      Status
 103  *
 104  * DESCRIPTION: Check for an unreferenced namespace object and emit a warning.
 105  *              We have to be careful, because some types and names are
 106  *              typically or always unreferenced, we don't want to issue
 107  *              excessive warnings. Note: Names that are declared within a
 108  *              control method are temporary, so we always issue a remark
 109  *              if they are not referenced.
 110  *
 111  ******************************************************************************/
 112
 113 static ACPI_STATUS
 114 LkIsObjectUsed (
 115     ACPI_HANDLE             ObjHandle,
 116     UINT32                  Level,
 117     void                    *Context,
 118     void                    **ReturnValue)
 119 {
 120     ACPI_NAMESPACE_NODE     *Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
 121     ACPI_NAMESPACE_NODE     *Next;
 122     ASL_METHOD_LOCAL        *MethodLocals;
 123     ASL_METHOD_LOCAL        *MethodArgs;
 124     UINT32                  i;
 125
 126
 127     if (Node->Type == ACPI_TYPE_METHOD)
 128     {
 129         if (!Node->Op || !Node->MethodLocals)
 130         {
 131             return (AE_OK);
 132         }
 133
 134         MethodLocals = (ASL_METHOD_LOCAL *) Node->MethodLocals;
 135         MethodArgs = (ASL_METHOD_LOCAL *) Node->MethodArgs;
 136
 137         /*
 138          * Analysis of LocalX variables
 139          */
 140         for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++)
 141         {
 142             /* Warn for Locals that are set but never referenced */
 143
 144             if ((MethodLocals[i].Flags & ASL_LOCAL_INITIALIZED) &&
 145                 (!(MethodLocals[i].Flags & ASL_LOCAL_REFERENCED)))
 146             {
 147                 sprintf (MsgBuffer, "Local%u", i);
 148                 AslError (ASL_WARNING, ASL_MSG_LOCAL_NOT_USED,
 149                     MethodLocals[i].Op, MsgBuffer);
 150             }
 151         }
 152
 153         /*
 154          * Analysis of ArgX variables (standard method arguments,
 155          * and remaining unused ArgX can also be used as locals)
 156          */
 157         for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++)
 158         {
 159             if (MethodArgs[i].Flags & ASL_ARG_IS_LOCAL)
 160             {
 161                 /* Warn if ArgX is being used as a local, but not referenced */
 162
 163                 if ((MethodArgs[i].Flags & ASL_ARG_INITIALIZED) &&
 164                     (!(MethodArgs[i].Flags & ASL_ARG_REFERENCED)))
 165                 {
 166                     sprintf (MsgBuffer, "Arg%u", i);
 167                     AslError (ASL_WARNING, ASL_MSG_ARG_AS_LOCAL_NOT_USED,
 168                         MethodArgs[i].Op, MsgBuffer);
 169                 }
 170             }
 171             else
 172             {
 173                 /*
 174                  * Remark if a normal method ArgX is not referenced.
 175                  * We ignore the predefined methods since often, not
 176                  * all arguments are needed or used.
 177                  */
 178                 if ((Node->Name.Ascii[0] != '_') &&
 179                     (!(MethodArgs[i].Flags & ASL_ARG_REFERENCED)))
 180                 {
 181                     sprintf (MsgBuffer, "Arg%u", i);
 182                     AslError (ASL_REMARK, ASL_MSG_ARG_NOT_USED,
 183                         MethodArgs[i].Op, MsgBuffer);
 184                 }
 185             }
 186         }
 187     }
 188
 189     /* Referenced flag is set during the namespace xref */
 190
 191     if (Node->Flags & ANOBJ_IS_REFERENCED)
 192     {
 193         return (AE_OK);
 194     }
 195
 196     if (!Node->Op)
 197     {
 198         return (AE_OK);
 199     }
 200
 201     /* These types are typically never directly referenced, ignore them */
 202
 203     switch (Node->Type)
 204     {
 205     case ACPI_TYPE_DEVICE:
 206     case ACPI_TYPE_PROCESSOR:
 207     case ACPI_TYPE_POWER:
 208     case ACPI_TYPE_THERMAL:
 209     case ACPI_TYPE_LOCAL_RESOURCE:
 210     case ACPI_TYPE_LOCAL_RESOURCE_FIELD: /* Names assigned to descriptor elements */
 211
 212         return (AE_OK);
 213
 214     default:
 215
 216         break;
 217     }
 218
 219     /* Determine if the name is within a control method */
 220
 221     Next = Node->Parent;
 222     while (Next)
 223     {
 224         if (Next->Type == ACPI_TYPE_METHOD)
 225         {
 226             /*
 227              * Name is within a method, therefore it is temporary.
 228              * Issue a remark even if it is a reserved name (starts
 229              * with an underscore).
 230              */
 231             sprintf (MsgBuffer, "Name [%4.4s] is within a method [%4.4s]",
 232                 Node->Name.Ascii, Next->Name.Ascii);
 233             AslError (ASL_REMARK, ASL_MSG_NOT_REFERENCED,
 234                 LkGetNameOp (Node->Op), MsgBuffer);
 235             return (AE_OK);
 236         }
 237
 238         Next = Next->Parent;
 239     }
 240
 241     /* The name is not within a control method */
 242
 243     /*
 244      * Ignore names that start with an underscore. These are the reserved
 245      * ACPI names and are typically not referenced since they are meant
 246      * to be called by the host OS.
 247      */
 248     if (Node->Name.Ascii[0] == '_')
 249     {
 250         return (AE_OK);
 251     }
 252
 253     /*
 254      * What remains is an unresolved user name that is not within a method.
 255      * However, the object could be referenced via another table, so issue
 256      * the warning at level 2.
 257      */
 258     AslError (ASL_WARNING2, ASL_MSG_NOT_REFERENCED,
 259         LkGetNameOp (Node->Op), NULL);
 260     return (AE_OK);
 261 }
 262
 263
 264 /*******************************************************************************
 265  *
 266  * FUNCTION:    LkGetNameOp
 267  *
 268  * PARAMETERS:  Op              - Current Op
 269  *
 270  * RETURN:      NameOp associated with the input op
 271  *
 272  * DESCRIPTION: Find the name declaration op associated with the operator
 273  *
 274  ******************************************************************************/
 275
 276 static ACPI_PARSE_OBJECT *
 277 LkGetNameOp (
 278     ACPI_PARSE_OBJECT       *Op)
 279 {
 280     const ACPI_OPCODE_INFO  *OpInfo;
 281     ACPI_PARSE_OBJECT       *NameOp = Op;
 282
 283
 284     OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
 285
 286
 287     /* Get the NamePath from the appropriate place */
 288
 289     if (OpInfo->Flags & AML_NAMED)
 290     {
 291         /* For nearly all NAMED operators, the name reference is the first child */
 292
 293         NameOp = Op->Asl.Child;
 294         if (Op->Asl.AmlOpcode == AML_ALIAS_OP)
 295         {
 296             /*
 297              * ALIAS is the only oddball opcode, the name declaration
 298              * (alias name) is the second operand
 299              */
 300             NameOp = Op->Asl.Child->Asl.Next;
 301         }
 302     }
 303     else if (OpInfo->Flags & AML_CREATE)
 304     {
 305         /* Name must appear as the last parameter */
 306
 307         NameOp = Op->Asl.Child;
 308         while (!(NameOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION))
 309         {
 310             NameOp = NameOp->Asl.Next;
 311         }
 312     }
 313
 314     return (NameOp);
 315 }