1 /*******************************************************************************
2 *
3 * Module Name: utownerid - Support for Table/Method Owner IDs
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2014, 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 "acnamesp.h"
47
48
49 #define _COMPONENT ACPI_UTILITIES
50 ACPI_MODULE_NAME ("utownerid")
51
52
53 /*******************************************************************************
54 *
55 * FUNCTION: AcpiUtAllocateOwnerId
56 *
57 * PARAMETERS: OwnerId - Where the new owner ID is returned
58 *
59 * RETURN: Status
60 *
61 * DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
62 * track objects created by the table or method, to be deleted
63 * when the method exits or the table is unloaded.
64 *
65 ******************************************************************************/
66
67 ACPI_STATUS
AcpiUtAllocateOwnerId(ACPI_OWNER_ID * OwnerId)68 AcpiUtAllocateOwnerId (
69 ACPI_OWNER_ID *OwnerId)
70 {
71 UINT32 i;
72 UINT32 j;
73 UINT32 k;
74 ACPI_STATUS Status;
75
76
77 ACPI_FUNCTION_TRACE (UtAllocateOwnerId);
78
79
80 /* Guard against multiple allocations of ID to the same location */
81
82 if (*OwnerId)
83 {
84 ACPI_ERROR ((AE_INFO, "Owner ID [0x%2.2X] already exists", *OwnerId));
85 return_ACPI_STATUS (AE_ALREADY_EXISTS);
86 }
87
88 /* Mutex for the global ID mask */
89
90 Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
91 if (ACPI_FAILURE (Status))
92 {
93 return_ACPI_STATUS (Status);
94 }
95
96 /*
97 * Find a free owner ID, cycle through all possible IDs on repeated
98 * allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index may have
99 * to be scanned twice.
100 */
101 for (i = 0, j = AcpiGbl_LastOwnerIdIndex;
102 i < (ACPI_NUM_OWNERID_MASKS + 1);
103 i++, j++)
104 {
105 if (j >= ACPI_NUM_OWNERID_MASKS)
106 {
107 j = 0; /* Wraparound to start of mask array */
108 }
109
110 for (k = AcpiGbl_NextOwnerIdOffset; k < 32; k++)
111 {
112 if (AcpiGbl_OwnerIdMask[j] == ACPI_UINT32_MAX)
113 {
114 /* There are no free IDs in this mask */
115
116 break;
117 }
118
119 if (!(AcpiGbl_OwnerIdMask[j] & (1 << k)))
120 {
121 /*
122 * Found a free ID. The actual ID is the bit index plus one,
123 * making zero an invalid Owner ID. Save this as the last ID
124 * allocated and update the global ID mask.
125 */
126 AcpiGbl_OwnerIdMask[j] |= (1 << k);
127
128 AcpiGbl_LastOwnerIdIndex = (UINT8) j;
129 AcpiGbl_NextOwnerIdOffset = (UINT8) (k + 1);
130
131 /*
132 * Construct encoded ID from the index and bit position
133 *
134 * Note: Last [j].k (bit 255) is never used and is marked
135 * permanently allocated (prevents +1 overflow)
136 */
137 *OwnerId = (ACPI_OWNER_ID) ((k + 1) + ACPI_MUL_32 (j));
138
139 ACPI_DEBUG_PRINT ((ACPI_DB_VALUES,
140 "Allocated OwnerId: %2.2X\n", (unsigned int) *OwnerId));
141 goto Exit;
142 }
143 }
144
145 AcpiGbl_NextOwnerIdOffset = 0;
146 }
147
148 /*
149 * All OwnerIds have been allocated. This typically should
150 * not happen since the IDs are reused after deallocation. The IDs are
151 * allocated upon table load (one per table) and method execution, and
152 * they are released when a table is unloaded or a method completes
153 * execution.
154 *
155 * If this error happens, there may be very deep nesting of invoked control
156 * methods, or there may be a bug where the IDs are not released.
157 */
158 Status = AE_OWNER_ID_LIMIT;
159 ACPI_ERROR ((AE_INFO,
160 "Could not allocate new OwnerId (255 max), AE_OWNER_ID_LIMIT"));
161
162 Exit:
163 (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
164 return_ACPI_STATUS (Status);
165 }
166
167
168 /*******************************************************************************
169 *
170 * FUNCTION: AcpiUtReleaseOwnerId
171 *
172 * PARAMETERS: OwnerIdPtr - Pointer to a previously allocated OwnerID
173 *
174 * RETURN: None. No error is returned because we are either exiting a
175 * control method or unloading a table. Either way, we would
176 * ignore any error anyway.
177 *
178 * DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
179 *
180 ******************************************************************************/
181
182 void
AcpiUtReleaseOwnerId(ACPI_OWNER_ID * OwnerIdPtr)183 AcpiUtReleaseOwnerId (
184 ACPI_OWNER_ID *OwnerIdPtr)
185 {
186 ACPI_OWNER_ID OwnerId = *OwnerIdPtr;
187 ACPI_STATUS Status;
188 UINT32 Index;
189 UINT32 Bit;
190
191
192 ACPI_FUNCTION_TRACE_U32 (UtReleaseOwnerId, OwnerId);
193
194
195 /* Always clear the input OwnerId (zero is an invalid ID) */
196
197 *OwnerIdPtr = 0;
198
199 /* Zero is not a valid OwnerID */
200
201 if (OwnerId == 0)
202 {
203 ACPI_ERROR ((AE_INFO, "Invalid OwnerId: 0x%2.2X", OwnerId));
204 return_VOID;
205 }
206
207 /* Mutex for the global ID mask */
208
209 Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
210 if (ACPI_FAILURE (Status))
211 {
212 return_VOID;
213 }
214
215 /* Normalize the ID to zero */
216
217 OwnerId--;
218
219 /* Decode ID to index/offset pair */
220
221 Index = ACPI_DIV_32 (OwnerId);
222 Bit = 1 << ACPI_MOD_32 (OwnerId);
223
224 /* Free the owner ID only if it is valid */
225
226 if (AcpiGbl_OwnerIdMask[Index] & Bit)
227 {
228 AcpiGbl_OwnerIdMask[Index] ^= Bit;
229 }
230 else
231 {
232 ACPI_ERROR ((AE_INFO,
233 "Release of non-allocated OwnerId: 0x%2.2X", OwnerId + 1));
234 }
235
236 (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
237 return_VOID;
238 }
239