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 |
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 |
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 | |