1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
*
* Module Name: utownerid - Support for Table/Method Owner IDs
*
******************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utownerid")
/*******************************************************************************
*
* FUNCTION: acpi_ut_allocate_owner_id
*
* PARAMETERS: owner_id - Where the new owner ID is returned
*
* RETURN: Status
*
* DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
* track objects created by the table or method, to be deleted
* when the method exits or the table is unloaded.
*
******************************************************************************/
acpi_status acpi_ut_allocate_owner_id(acpi_owner_id *owner_id)
{
u32 i;
u32 j;
u32 k;
acpi_status status;
ACPI_FUNCTION_TRACE(ut_allocate_owner_id);
/* Guard against multiple allocations of ID to the same location */
if (*owner_id) {
ACPI_ERROR((AE_INFO,
"Owner ID [0x%3.3X] already exists", *owner_id));
return_ACPI_STATUS(AE_ALREADY_EXISTS);
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Find a free owner ID, cycle through all possible IDs on repeated
* allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index
* may have to be scanned twice.
*/
for (i = 0, j = acpi_gbl_last_owner_id_index;
i < (ACPI_NUM_OWNERID_MASKS + 1); i++, j++) {
if (j >= ACPI_NUM_OWNERID_MASKS) {
j = 0; /* Wraparound to start of mask array */
}
for (k = acpi_gbl_next_owner_id_offset; k < 32; k++) {
if (acpi_gbl_owner_id_mask[j] == ACPI_UINT32_MAX) {
/* There are no free IDs in this mask */
break;
}
/*
* Note: the u32 cast ensures that 1 is stored as a unsigned
* integer. Omitting the cast may result in 1 being stored as an
* int. Some compilers or runtime error detection may flag this as
* an error.
*/
if (!(acpi_gbl_owner_id_mask[j] & ((u32)1 << k))) {
/*
* Found a free ID. The actual ID is the bit index plus one,
* making zero an invalid Owner ID. Save this as the last ID
* allocated and update the global ID mask.
*/
acpi_gbl_owner_id_mask[j] |= ((u32)1 << k);
acpi_gbl_last_owner_id_index = (u8)j;
acpi_gbl_next_owner_id_offset = (u8)(k + 1);
/*
* Construct encoded ID from the index and bit position
*
* Note: Last [j].k (bit 4095) is never used and is marked
* permanently allocated (prevents +1 overflow)
*/
*owner_id =
(acpi_owner_id)((k + 1) + ACPI_MUL_32(j));
ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
"Allocated OwnerId: 0x%3.3X\n",
(unsigned int)*owner_id));
goto exit;
}
}
acpi_gbl_next_owner_id_offset = 0;
}
/*
* All owner_ids have been allocated. This typically should
* not happen since the IDs are reused after deallocation. The IDs are
* allocated upon table load (one per table) and method execution, and
* they are released when a table is unloaded or a method completes
* execution.
*
* If this error happens, there may be very deep nesting of invoked
* control methods, or there may be a bug where the IDs are not released.
*/
status = AE_OWNER_ID_LIMIT;
ACPI_ERROR((AE_INFO,
"Could not allocate new OwnerId (4095 max), AE_OWNER_ID_LIMIT"));
exit:
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_release_owner_id
*
* PARAMETERS: owner_id_ptr - Pointer to a previously allocated owner_ID
*
* RETURN: None. No error is returned because we are either exiting a
* control method or unloading a table. Either way, we would
* ignore any error anyway.
*
* DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
*
******************************************************************************/
void acpi_ut_release_owner_id(acpi_owner_id *owner_id_ptr)
{
acpi_owner_id owner_id = *owner_id_ptr;
acpi_status status;
u32 index;
u32 bit;
ACPI_FUNCTION_TRACE_U32(ut_release_owner_id, owner_id);
/* Always clear the input owner_id (zero is an invalid ID) */
*owner_id_ptr = 0;
/* Zero is not a valid owner_ID */
if (owner_id == 0) {
ACPI_ERROR((AE_INFO, "Invalid OwnerId: 0x%3.3X", owner_id));
return_VOID;
}
/* Mutex for the global ID mask */
status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
if (ACPI_FAILURE(status)) {
return_VOID;
}
/* Normalize the ID to zero */
owner_id--;
/* Decode ID to index/offset pair */
index = ACPI_DIV_32(owner_id);
bit = (u32)1 << ACPI_MOD_32(owner_id);
/* Free the owner ID only if it is valid */
if (acpi_gbl_owner_id_mask[index] & bit) {
acpi_gbl_owner_id_mask[index] ^= bit;
} else {
ACPI_ERROR((AE_INFO,
"Attempted release of non-allocated OwnerId: 0x%3.3X",
owner_id + 1));
}
(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
return_VOID;
}
|
