1 /******************************************************************************
2  *
3  * Module Name: tbfind   - find table
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 "acpi.h"
45 #include "accommon.h"
46 #include "actables.h"
47 
48 #define _COMPONENT          ACPI_TABLES
49         ACPI_MODULE_NAME    ("tbfind")
50 
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    AcpiTbFindTable
55  *
56  * PARAMETERS:  Signature           - String with ACPI table signature
57  *              OemId               - String with the table OEM ID
58  *              OemTableId          - String with the OEM Table ID
59  *              TableIndex          - Where the table index is returned
60  *
61  * RETURN:      Status and table index
62  *
63  * DESCRIPTION: Find an ACPI table (in the RSDT/XSDT) that matches the
64  *              Signature, OEM ID and OEM Table ID. Returns an index that can
65  *              be used to get the table header or entire table.
66  *
67  ******************************************************************************/
68 
69 ACPI_STATUS
70 AcpiTbFindTable (
71     char                    *Signature,
72     char                    *OemId,
73     char                    *OemTableId,
74     UINT32                  *TableIndex)
75 {
76     ACPI_STATUS             Status = AE_OK;
77     ACPI_TABLE_HEADER       Header;
78     UINT32                  i;
79 
80 
81     ACPI_FUNCTION_TRACE (TbFindTable);
82 
83 
84     /* Validate the input table signature */
85 
86     if (!AcpiUtValidNameseg (Signature))
87     {
88         return_ACPI_STATUS (AE_BAD_SIGNATURE);
89     }
90 
91     /* Don't allow the OEM strings to be too long */
92 
93     if ((strlen (OemId) > ACPI_OEM_ID_SIZE) ||
94         (strlen (OemTableId) > ACPI_OEM_TABLE_ID_SIZE))
95     {
96         return_ACPI_STATUS (AE_AML_STRING_LIMIT);
97     }
98 
99     /* Normalize the input strings */
100 
101     memset (&Header, 0, sizeof (ACPI_TABLE_HEADER));
102     ACPI_MOVE_NAME (Header.Signature, Signature);
103     strncpy (Header.OemId, OemId, ACPI_OEM_ID_SIZE);
104     strncpy (Header.OemTableId, OemTableId, ACPI_OEM_TABLE_ID_SIZE);
105 
106     /* Search for the table */
107 
108     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
109     for (i = 0; i < AcpiGbl_RootTableList.CurrentTableCount; ++i)
110     {
111         if (memcmp (&(AcpiGbl_RootTableList.Tables[i].Signature),
112             Header.Signature, ACPI_NAME_SIZE))
113         {
114             /* Not the requested table */
115 
116             continue;
117         }
118 
119         /* Table with matching signature has been found */
120 
121         if (!AcpiGbl_RootTableList.Tables[i].Pointer)
122         {
123             /* Table is not currently mapped, map it */
124 
125             Status = AcpiTbValidateTable (&AcpiGbl_RootTableList.Tables[i]);
126             if (ACPI_FAILURE (Status))
127             {
128                 goto UnlockAndExit;
129             }
130 
131             if (!AcpiGbl_RootTableList.Tables[i].Pointer)
132             {
133                 continue;
134             }
135         }
136 
137         /* Check for table match on all IDs */
138 
139         if (!memcmp (AcpiGbl_RootTableList.Tables[i].Pointer->Signature,
140                 Header.Signature, ACPI_NAME_SIZE) &&
141             (!OemId[0] ||
142              !memcmp (AcpiGbl_RootTableList.Tables[i].Pointer->OemId,
143                  Header.OemId, ACPI_OEM_ID_SIZE)) &&
144             (!OemTableId[0] ||
145              !memcmp (AcpiGbl_RootTableList.Tables[i].Pointer->OemTableId,
146                  Header.OemTableId, ACPI_OEM_TABLE_ID_SIZE)))
147         {
148             *TableIndex = i;
149 
150             ACPI_DEBUG_PRINT ((ACPI_DB_TABLES, "Found table [%4.4s]\n",
151                 Header.Signature));
152             goto UnlockAndExit;
153         }
154     }
155     Status = AE_NOT_FOUND;
156 
157 UnlockAndExit:
158     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
159     return_ACPI_STATUS (Status);
160 }
161