1 /*******************************************************************************
2 *
3 * Module Name: utownerid - Support for Table/Method Owner IDs
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 "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,
85 "Owner ID [0x%2.2X] already exists", *OwnerId));
86 return_ACPI_STATUS (AE_ALREADY_EXISTS);
87 }
88
89 /* Mutex for the global ID mask */
90
91 Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
92 if (ACPI_FAILURE (Status))
93 {
94 return_ACPI_STATUS (Status);
95 }
96
97 /*
98 * Find a free owner ID, cycle through all possible IDs on repeated
99 * allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index
100 * may have to be scanned twice.
101 */
102 for (i = 0, j = AcpiGbl_LastOwnerIdIndex;
103 i < (ACPI_NUM_OWNERID_MASKS + 1);
104 i++, j++)
105 {
106 if (j >= ACPI_NUM_OWNERID_MASKS)
107 {
108 j = 0; /* Wraparound to start of mask array */
109 }
110
111 for (k = AcpiGbl_NextOwnerIdOffset; k < 32; k++)
112 {
113 if (AcpiGbl_OwnerIdMask[j] == ACPI_UINT32_MAX)
114 {
115 /* There are no free IDs in this mask */
116
117 break;
118 }
119
120 if (!(AcpiGbl_OwnerIdMask[j] & (1 << k)))
121 {
122 /*
123 * Found a free ID. The actual ID is the bit index plus one,
124 * making zero an invalid Owner ID. Save this as the last ID
125 * allocated and update the global ID mask.
126 */
127 AcpiGbl_OwnerIdMask[j] |= (1 << k);
128
129 AcpiGbl_LastOwnerIdIndex = (UINT8) j;
130 AcpiGbl_NextOwnerIdOffset = (UINT8) (k + 1);
131
132 /*
133 * Construct encoded ID from the index and bit position
134 *
135 * Note: Last [j].k (bit 255) is never used and is marked
136 * permanently allocated (prevents +1 overflow)
137 */
138 *OwnerId = (ACPI_OWNER_ID) ((k + 1) + ACPI_MUL_32 (j));
139
140 ACPI_DEBUG_PRINT ((ACPI_DB_VALUES,
141 "Allocated OwnerId: %2.2X\n", (unsigned int) *OwnerId));
142 goto Exit;
143 }
144 }
145
146 AcpiGbl_NextOwnerIdOffset = 0;
147 }
148
149 /*
150 * All OwnerIds have been allocated. This typically should
151 * not happen since the IDs are reused after deallocation. The IDs are
152 * allocated upon table load (one per table) and method execution, and
153 * they are released when a table is unloaded or a method completes
154 * execution.
155 *
156 * If this error happens, there may be very deep nesting of invoked
157 * control methods, or there may be a bug where the IDs are not released.
158 */
159 Status = AE_OWNER_ID_LIMIT;
160 ACPI_ERROR ((AE_INFO,
161 "Could not allocate new OwnerId (255 max), AE_OWNER_ID_LIMIT"));
162
163 Exit:
164 (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
165 return_ACPI_STATUS (Status);
166 }
167
168
169 /*******************************************************************************
170 *
171 * FUNCTION: AcpiUtReleaseOwnerId
172 *
173 * PARAMETERS: OwnerIdPtr - Pointer to a previously allocated OwnerID
174 *
175 * RETURN: None. No error is returned because we are either exiting a
176 * control method or unloading a table. Either way, we would
177 * ignore any error anyway.
178 *
179 * DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
180 *
181 ******************************************************************************/
182
183 void
AcpiUtReleaseOwnerId(ACPI_OWNER_ID * OwnerIdPtr)184 AcpiUtReleaseOwnerId (
185 ACPI_OWNER_ID *OwnerIdPtr)
186 {
187 ACPI_OWNER_ID OwnerId = *OwnerIdPtr;
188 ACPI_STATUS Status;
189 UINT32 Index;
190 UINT32 Bit;
191
192
193 ACPI_FUNCTION_TRACE_U32 (UtReleaseOwnerId, OwnerId);
194
195
196 /* Always clear the input OwnerId (zero is an invalid ID) */
197
198 *OwnerIdPtr = 0;
199
200 /* Zero is not a valid OwnerID */
201
202 if (OwnerId == 0)
203 {
204 ACPI_ERROR ((AE_INFO, "Invalid OwnerId: 0x%2.2X", OwnerId));
205 return_VOID;
206 }
207
208 /* Mutex for the global ID mask */
209
210 Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
211 if (ACPI_FAILURE (Status))
212 {
213 return_VOID;
214 }
215
216 /* Normalize the ID to zero */
217
218 OwnerId--;
219
220 /* Decode ID to index/offset pair */
221
222 Index = ACPI_DIV_32 (OwnerId);
223 Bit = 1 << ACPI_MOD_32 (OwnerId);
224
225 /* Free the owner ID only if it is valid */
226
227 if (AcpiGbl_OwnerIdMask[Index] & Bit)
228 {
229 AcpiGbl_OwnerIdMask[Index] ^= Bit;
230 }
231 else
232 {
233 ACPI_ERROR ((AE_INFO,
234 "Release of non-allocated OwnerId: 0x%2.2X", OwnerId + 1));
235 }
236
237 (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
238 return_VOID;
239 }
240