1 /*******************************************************************************
2  *
3  * Module Name: utownerid - Support for Table/Method Owner IDs
4  *
5  ******************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2018, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include "acpi.h"
153 #include "accommon.h"
154 #include "acnamesp.h"
155 
156 
157 #define _COMPONENT          ACPI_UTILITIES
158         ACPI_MODULE_NAME    ("utownerid")
159 
160 
161 /*******************************************************************************
162  *
163  * FUNCTION:    AcpiUtAllocateOwnerId
164  *
165  * PARAMETERS:  OwnerId         - Where the new owner ID is returned
166  *
167  * RETURN:      Status
168  *
169  * DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
170  *              track objects created by the table or method, to be deleted
171  *              when the method exits or the table is unloaded.
172  *
173  ******************************************************************************/
174 
175 ACPI_STATUS
AcpiUtAllocateOwnerId(ACPI_OWNER_ID * OwnerId)176 AcpiUtAllocateOwnerId (
177     ACPI_OWNER_ID           *OwnerId)
178 {
179     UINT32                  i;
180     UINT32                  j;
181     UINT32                  k;
182     ACPI_STATUS             Status;
183 
184 
185     ACPI_FUNCTION_TRACE (UtAllocateOwnerId);
186 
187 
188     /* Guard against multiple allocations of ID to the same location */
189 
190     if (*OwnerId)
191     {
192         ACPI_ERROR ((AE_INFO,
193             "Owner ID [0x%2.2X] already exists", *OwnerId));
194         return_ACPI_STATUS (AE_ALREADY_EXISTS);
195     }
196 
197     /* Mutex for the global ID mask */
198 
199     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
200     if (ACPI_FAILURE (Status))
201     {
202         return_ACPI_STATUS (Status);
203     }
204 
205     /*
206      * Find a free owner ID, cycle through all possible IDs on repeated
207      * allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index
208      * may have to be scanned twice.
209      */
210     for (i = 0, j = AcpiGbl_LastOwnerIdIndex;
211          i < (ACPI_NUM_OWNERID_MASKS + 1);
212          i++, j++)
213     {
214         if (j >= ACPI_NUM_OWNERID_MASKS)
215         {
216             j = 0;  /* Wraparound to start of mask array */
217         }
218 
219         for (k = AcpiGbl_NextOwnerIdOffset; k < 32; k++)
220         {
221             if (AcpiGbl_OwnerIdMask[j] == ACPI_UINT32_MAX)
222             {
223                 /* There are no free IDs in this mask */
224 
225                 break;
226             }
227 
228             /*
229              * Note: the UINT32 cast ensures that 1 is stored as a unsigned
230              * integer. Omitting the cast may result in 1 being stored as an
231              * int. Some compilers or runtime error detection may flag this as
232              * an error.
233              */
234             if (!(AcpiGbl_OwnerIdMask[j] & ((UINT32) 1 << k)))
235             {
236                 /*
237                  * Found a free ID. The actual ID is the bit index plus one,
238                  * making zero an invalid Owner ID. Save this as the last ID
239                  * allocated and update the global ID mask.
240                  */
241                 AcpiGbl_OwnerIdMask[j] |= ((UINT32) 1 << k);
242 
243                 AcpiGbl_LastOwnerIdIndex = (UINT8) j;
244                 AcpiGbl_NextOwnerIdOffset = (UINT8) (k + 1);
245 
246                 /*
247                  * Construct encoded ID from the index and bit position
248                  *
249                  * Note: Last [j].k (bit 255) is never used and is marked
250                  * permanently allocated (prevents +1 overflow)
251                  */
252                 *OwnerId = (ACPI_OWNER_ID) ((k + 1) + ACPI_MUL_32 (j));
253 
254                 ACPI_DEBUG_PRINT ((ACPI_DB_VALUES,
255                     "Allocated OwnerId: %2.2X\n", (unsigned int) *OwnerId));
256                 goto Exit;
257             }
258         }
259 
260         AcpiGbl_NextOwnerIdOffset = 0;
261     }
262 
263     /*
264      * All OwnerIds have been allocated. This typically should
265      * not happen since the IDs are reused after deallocation. The IDs are
266      * allocated upon table load (one per table) and method execution, and
267      * they are released when a table is unloaded or a method completes
268      * execution.
269      *
270      * If this error happens, there may be very deep nesting of invoked
271      * control methods, or there may be a bug where the IDs are not released.
272      */
273     Status = AE_OWNER_ID_LIMIT;
274     ACPI_ERROR ((AE_INFO,
275         "Could not allocate new OwnerId (255 max), AE_OWNER_ID_LIMIT"));
276 
277 Exit:
278     (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
279     return_ACPI_STATUS (Status);
280 }
281 
282 
283 /*******************************************************************************
284  *
285  * FUNCTION:    AcpiUtReleaseOwnerId
286  *
287  * PARAMETERS:  OwnerIdPtr          - Pointer to a previously allocated OwnerID
288  *
289  * RETURN:      None. No error is returned because we are either exiting a
290  *              control method or unloading a table. Either way, we would
291  *              ignore any error anyway.
292  *
293  * DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
294  *
295  ******************************************************************************/
296 
297 void
AcpiUtReleaseOwnerId(ACPI_OWNER_ID * OwnerIdPtr)298 AcpiUtReleaseOwnerId (
299     ACPI_OWNER_ID           *OwnerIdPtr)
300 {
301     ACPI_OWNER_ID           OwnerId = *OwnerIdPtr;
302     ACPI_STATUS             Status;
303     UINT32                  Index;
304     UINT32                  Bit;
305 
306 
307     ACPI_FUNCTION_TRACE_U32 (UtReleaseOwnerId, OwnerId);
308 
309 
310     /* Always clear the input OwnerId (zero is an invalid ID) */
311 
312     *OwnerIdPtr = 0;
313 
314     /* Zero is not a valid OwnerID */
315 
316     if (OwnerId == 0)
317     {
318         ACPI_ERROR ((AE_INFO, "Invalid OwnerId: 0x%2.2X", OwnerId));
319         return_VOID;
320     }
321 
322     /* Mutex for the global ID mask */
323 
324     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
325     if (ACPI_FAILURE (Status))
326     {
327         return_VOID;
328     }
329 
330     /* Normalize the ID to zero */
331 
332     OwnerId--;
333 
334     /* Decode ID to index/offset pair */
335 
336     Index = ACPI_DIV_32 (OwnerId);
337     Bit = (UINT32) 1 << ACPI_MOD_32 (OwnerId);
338 
339     /* Free the owner ID only if it is valid */
340 
341     if (AcpiGbl_OwnerIdMask[Index] & Bit)
342     {
343         AcpiGbl_OwnerIdMask[Index] ^= Bit;
344     }
345     else
346     {
347         ACPI_ERROR ((AE_INFO,
348             "Release of non-allocated OwnerId: 0x%2.2X", OwnerId + 1));
349     }
350 
351     (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
352     return_VOID;
353 }
354