xref: /freebsd/sys/contrib/dev/acpica/compiler/asllookup.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
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 <contrib/dev/acpica/compiler/aslcompiler.h>
45 #include "aslcompiler.y.h"
46 #include <contrib/dev/acpica/include/acparser.h>
47 #include <contrib/dev/acpica/include/amlcode.h>
48 #include <contrib/dev/acpica/include/acnamesp.h>
49 #include <contrib/dev/acpica/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 }
316