Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / evxfregn.c
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: evxfregn - External Interfaces, ACPI Operation Regions and
5  *                         Address Spaces.
6  *
7  * Copyright (C) 2000 - 2018, Intel Corp.
8  *
9  *****************************************************************************/
10
11 #define EXPORT_ACPI_INTERFACES
12
13 #include <acpi/acpi.h>
14 #include "accommon.h"
15 #include "acnamesp.h"
16 #include "acevents.h"
17
18 #define _COMPONENT          ACPI_EVENTS
19 ACPI_MODULE_NAME("evxfregn")
20
21 /*******************************************************************************
22  *
23  * FUNCTION:    acpi_install_address_space_handler
24  *
25  * PARAMETERS:  device          - Handle for the device
26  *              space_id        - The address space ID
27  *              handler         - Address of the handler
28  *              setup           - Address of the setup function
29  *              context         - Value passed to the handler on each access
30  *
31  * RETURN:      Status
32  *
33  * DESCRIPTION: Install a handler for all op_regions of a given space_id.
34  *
35  * NOTE: This function should only be called after acpi_enable_subsystem has
36  * been called. This is because any _REG methods associated with the Space ID
37  * are executed here, and these methods can only be safely executed after
38  * the default handlers have been installed and the hardware has been
39  * initialized (via acpi_enable_subsystem.)
40  *
41  ******************************************************************************/
42 acpi_status
43 acpi_install_address_space_handler(acpi_handle device,
44                                    acpi_adr_space_type space_id,
45                                    acpi_adr_space_handler handler,
46                                    acpi_adr_space_setup setup, void *context)
47 {
48         struct acpi_namespace_node *node;
49         acpi_status status;
50
51         ACPI_FUNCTION_TRACE(acpi_install_address_space_handler);
52
53         /* Parameter validation */
54
55         if (!device) {
56                 return_ACPI_STATUS(AE_BAD_PARAMETER);
57         }
58
59         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
60         if (ACPI_FAILURE(status)) {
61                 return_ACPI_STATUS(status);
62         }
63
64         /* Convert and validate the device handle */
65
66         node = acpi_ns_validate_handle(device);
67         if (!node) {
68                 status = AE_BAD_PARAMETER;
69                 goto unlock_and_exit;
70         }
71
72         /* Install the handler for all Regions for this Space ID */
73
74         status =
75             acpi_ev_install_space_handler(node, space_id, handler, setup,
76                                           context);
77         if (ACPI_FAILURE(status)) {
78                 goto unlock_and_exit;
79         }
80
81         /* Run all _REG methods for this address space */
82
83         acpi_ev_execute_reg_methods(node, space_id, ACPI_REG_CONNECT);
84
85 unlock_and_exit:
86         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
87         return_ACPI_STATUS(status);
88 }
89
90 ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler)
91
92 /*******************************************************************************
93  *
94  * FUNCTION:    acpi_remove_address_space_handler
95  *
96  * PARAMETERS:  device          - Handle for the device
97  *              space_id        - The address space ID
98  *              handler         - Address of the handler
99  *
100  * RETURN:      Status
101  *
102  * DESCRIPTION: Remove a previously installed handler.
103  *
104  ******************************************************************************/
105 acpi_status
106 acpi_remove_address_space_handler(acpi_handle device,
107                                   acpi_adr_space_type space_id,
108                                   acpi_adr_space_handler handler)
109 {
110         union acpi_operand_object *obj_desc;
111         union acpi_operand_object *handler_obj;
112         union acpi_operand_object *region_obj;
113         union acpi_operand_object **last_obj_ptr;
114         struct acpi_namespace_node *node;
115         acpi_status status;
116
117         ACPI_FUNCTION_TRACE(acpi_remove_address_space_handler);
118
119         /* Parameter validation */
120
121         if (!device) {
122                 return_ACPI_STATUS(AE_BAD_PARAMETER);
123         }
124
125         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
126         if (ACPI_FAILURE(status)) {
127                 return_ACPI_STATUS(status);
128         }
129
130         /* Convert and validate the device handle */
131
132         node = acpi_ns_validate_handle(device);
133         if (!node ||
134             ((node->type != ACPI_TYPE_DEVICE) &&
135              (node->type != ACPI_TYPE_PROCESSOR) &&
136              (node->type != ACPI_TYPE_THERMAL) &&
137              (node != acpi_gbl_root_node))) {
138                 status = AE_BAD_PARAMETER;
139                 goto unlock_and_exit;
140         }
141
142         /* Make sure the internal object exists */
143
144         obj_desc = acpi_ns_get_attached_object(node);
145         if (!obj_desc) {
146                 status = AE_NOT_EXIST;
147                 goto unlock_and_exit;
148         }
149
150         /* Find the address handler the user requested */
151
152         handler_obj = obj_desc->common_notify.handler;
153         last_obj_ptr = &obj_desc->common_notify.handler;
154         while (handler_obj) {
155
156                 /* We have a handler, see if user requested this one */
157
158                 if (handler_obj->address_space.space_id == space_id) {
159
160                         /* Handler must be the same as the installed handler */
161
162                         if (handler_obj->address_space.handler != handler) {
163                                 status = AE_BAD_PARAMETER;
164                                 goto unlock_and_exit;
165                         }
166
167                         /* Matched space_id, first dereference this in the Regions */
168
169                         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
170                                           "Removing address handler %p(%p) for region %s "
171                                           "on Device %p(%p)\n",
172                                           handler_obj, handler,
173                                           acpi_ut_get_region_name(space_id),
174                                           node, obj_desc));
175
176                         region_obj = handler_obj->address_space.region_list;
177
178                         /* Walk the handler's region list */
179
180                         while (region_obj) {
181                                 /*
182                                  * First disassociate the handler from the region.
183                                  *
184                                  * NOTE: this doesn't mean that the region goes away
185                                  * The region is just inaccessible as indicated to
186                                  * the _REG method
187                                  */
188                                 acpi_ev_detach_region(region_obj, TRUE);
189
190                                 /*
191                                  * Walk the list: Just grab the head because the
192                                  * detach_region removed the previous head.
193                                  */
194                                 region_obj =
195                                     handler_obj->address_space.region_list;
196                         }
197
198                         /* Remove this Handler object from the list */
199
200                         *last_obj_ptr = handler_obj->address_space.next;
201
202                         /* Now we can delete the handler object */
203
204                         acpi_ut_remove_reference(handler_obj);
205                         goto unlock_and_exit;
206                 }
207
208                 /* Walk the linked list of handlers */
209
210                 last_obj_ptr = &handler_obj->address_space.next;
211                 handler_obj = handler_obj->address_space.next;
212         }
213
214         /* The handler does not exist */
215
216         ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
217                           "Unable to remove address handler %p for %s(%X), DevNode %p, obj %p\n",
218                           handler, acpi_ut_get_region_name(space_id), space_id,
219                           node, obj_desc));
220
221         status = AE_NOT_EXIST;
222
223 unlock_and_exit:
224         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
225         return_ACPI_STATUS(status);
226 }
227
228 ACPI_EXPORT_SYMBOL(acpi_remove_address_space_handler)