xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utownerid.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
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 <contrib/dev/acpica/include/acpi.h>
45 #include <contrib/dev/acpica/include/accommon.h>
46 #include <contrib/dev/acpica/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