[PATCH] memory hotplug: move section_mem_map alloc to sparse.c
[linux-2.6.git] / drivers / acpi / acpi_memhotplug.c
1 /*
2  * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
3  *
4  * All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or (at
9  * your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
14  * NON INFRINGEMENT.  See the GNU General Public License for more
15  * details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  *
21  *
22  * ACPI based HotPlug driver that supports Memory Hotplug
23  * This driver fields notifications from firmare for memory add
24  * and remove operations and alerts the VM of the affected memory
25  * ranges.
26  */
27
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/types.h>
32 #include <linux/memory_hotplug.h>
33 #include <acpi/acpi_drivers.h>
34
35 #define ACPI_MEMORY_DEVICE_COMPONENT            0x08000000UL
36 #define ACPI_MEMORY_DEVICE_CLASS                "memory"
37 #define ACPI_MEMORY_DEVICE_HID                  "PNP0C80"
38 #define ACPI_MEMORY_DEVICE_DRIVER_NAME          "Hotplug Mem Driver"
39 #define ACPI_MEMORY_DEVICE_NAME                 "Hotplug Mem Device"
40
41 #define _COMPONENT              ACPI_MEMORY_DEVICE_COMPONENT
42
43 ACPI_MODULE_NAME("acpi_memory")
44     MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
45 MODULE_DESCRIPTION(ACPI_MEMORY_DEVICE_DRIVER_NAME);
46 MODULE_LICENSE("GPL");
47
48 /* ACPI _STA method values */
49 #define ACPI_MEMORY_STA_PRESENT         (0x00000001UL)
50 #define ACPI_MEMORY_STA_ENABLED         (0x00000002UL)
51 #define ACPI_MEMORY_STA_FUNCTIONAL      (0x00000008UL)
52
53 /* Memory Device States */
54 #define MEMORY_INVALID_STATE    0
55 #define MEMORY_POWER_ON_STATE   1
56 #define MEMORY_POWER_OFF_STATE  2
57
58 static int acpi_memory_device_add(struct acpi_device *device);
59 static int acpi_memory_device_remove(struct acpi_device *device, int type);
60
61 static struct acpi_driver acpi_memory_device_driver = {
62         .name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
63         .class = ACPI_MEMORY_DEVICE_CLASS,
64         .ids = ACPI_MEMORY_DEVICE_HID,
65         .ops = {
66                 .add = acpi_memory_device_add,
67                 .remove = acpi_memory_device_remove,
68                 },
69 };
70
71 struct acpi_memory_device {
72         acpi_handle handle;
73         unsigned int state;     /* State of the memory device */
74         unsigned short cache_attribute; /* memory cache attribute */
75         unsigned short read_write_attribute;    /* memory read/write attribute */
76         u64 start_addr;         /* Memory Range start physical addr */
77         u64 end_addr;           /* Memory Range end physical addr */
78 };
79
80 static int
81 acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
82 {
83         acpi_status status;
84         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
85         struct acpi_resource *resource = NULL;
86         struct acpi_resource_address64 address64;
87
88         ACPI_FUNCTION_TRACE("acpi_memory_get_device_resources");
89
90         /* Get the range from the _CRS */
91         status = acpi_get_current_resources(mem_device->handle, &buffer);
92         if (ACPI_FAILURE(status))
93                 return_VALUE(-EINVAL);
94
95         resource = (struct acpi_resource *)buffer.pointer;
96         status = acpi_resource_to_address64(resource, &address64);
97         if (ACPI_SUCCESS(status)) {
98                 if (address64.resource_type == ACPI_MEMORY_RANGE) {
99                         /* Populate the structure */
100                         mem_device->cache_attribute =
101                             address64.attribute.memory.cache_attribute;
102                         mem_device->read_write_attribute =
103                             address64.attribute.memory.read_write_attribute;
104                         mem_device->start_addr = address64.min_address_range;
105                         mem_device->end_addr = address64.max_address_range;
106                 }
107         }
108
109         acpi_os_free(buffer.pointer);
110         return_VALUE(0);
111 }
112
113 static int
114 acpi_memory_get_device(acpi_handle handle,
115                        struct acpi_memory_device **mem_device)
116 {
117         acpi_status status;
118         acpi_handle phandle;
119         struct acpi_device *device = NULL;
120         struct acpi_device *pdevice = NULL;
121
122         ACPI_FUNCTION_TRACE("acpi_memory_get_device");
123
124         if (!acpi_bus_get_device(handle, &device) && device)
125                 goto end;
126
127         status = acpi_get_parent(handle, &phandle);
128         if (ACPI_FAILURE(status)) {
129                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_get_parent\n"));
130                 return_VALUE(-EINVAL);
131         }
132
133         /* Get the parent device */
134         status = acpi_bus_get_device(phandle, &pdevice);
135         if (ACPI_FAILURE(status)) {
136                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
137                                   "Error in acpi_bus_get_device\n"));
138                 return_VALUE(-EINVAL);
139         }
140
141         /*
142          * Now add the notified device.  This creates the acpi_device
143          * and invokes .add function
144          */
145         status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
146         if (ACPI_FAILURE(status)) {
147                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_bus_add\n"));
148                 return_VALUE(-EINVAL);
149         }
150
151       end:
152         *mem_device = acpi_driver_data(device);
153         if (!(*mem_device)) {
154                 printk(KERN_ERR "\n driver data not found");
155                 return_VALUE(-ENODEV);
156         }
157
158         return_VALUE(0);
159 }
160
161 static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
162 {
163         unsigned long current_status;
164
165         ACPI_FUNCTION_TRACE("acpi_memory_check_device");
166
167         /* Get device present/absent information from the _STA */
168         if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
169                                                NULL, &current_status)))
170                 return_VALUE(-ENODEV);
171         /*
172          * Check for device status. Device should be
173          * present/enabled/functioning.
174          */
175         if (!((current_status & ACPI_MEMORY_STA_PRESENT)
176               && (current_status & ACPI_MEMORY_STA_ENABLED)
177               && (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
178                 return_VALUE(-ENODEV);
179
180         return_VALUE(0);
181 }
182
183 static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
184 {
185         int result;
186
187         ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
188
189         /* Get the range from the _CRS */
190         result = acpi_memory_get_device_resources(mem_device);
191         if (result) {
192                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
193                                   "\nget_device_resources failed\n"));
194                 mem_device->state = MEMORY_INVALID_STATE;
195                 return result;
196         }
197
198         /*
199          * Tell the VM there is more memory here...
200          * Note: Assume that this function returns zero on success
201          */
202         result = add_memory(mem_device->start_addr,
203                             (mem_device->end_addr - mem_device->start_addr) + 1);
204         if (result) {
205                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
206                 mem_device->state = MEMORY_INVALID_STATE;
207                 return result;
208         }
209
210         return result;
211 }
212
213 static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
214 {
215         acpi_status status;
216         struct acpi_object_list arg_list;
217         union acpi_object arg;
218         unsigned long current_status;
219
220         ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
221
222         /* Issue the _EJ0 command */
223         arg_list.count = 1;
224         arg_list.pointer = &arg;
225         arg.type = ACPI_TYPE_INTEGER;
226         arg.integer.value = 1;
227         status = acpi_evaluate_object(mem_device->handle,
228                                       "_EJ0", &arg_list, NULL);
229         /* Return on _EJ0 failure */
230         if (ACPI_FAILURE(status)) {
231                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "_EJ0 failed.\n"));
232                 return_VALUE(-ENODEV);
233         }
234
235         /* Evalute _STA to check if the device is disabled */
236         status = acpi_evaluate_integer(mem_device->handle, "_STA",
237                                        NULL, &current_status);
238         if (ACPI_FAILURE(status))
239                 return_VALUE(-ENODEV);
240
241         /* Check for device status.  Device should be disabled */
242         if (current_status & ACPI_MEMORY_STA_ENABLED)
243                 return_VALUE(-EINVAL);
244
245         return_VALUE(0);
246 }
247
248 static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
249 {
250         int result;
251         u64 start = mem_device->start_addr;
252         u64 len = mem_device->end_addr - start + 1;
253         unsigned long attr = mem_device->read_write_attribute;
254
255         ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
256
257         /*
258          * Ask the VM to offline this memory range.
259          * Note: Assume that this function returns zero on success
260          */
261         result = remove_memory(start, len);
262         if (result) {
263                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
264                 return_VALUE(result);
265         }
266
267         /* Power-off and eject the device */
268         result = acpi_memory_powerdown_device(mem_device);
269         if (result) {
270                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
271                                   "Device Power Down failed.\n"));
272                 /* Set the status of the device to invalid */
273                 mem_device->state = MEMORY_INVALID_STATE;
274                 return result;
275         }
276
277         mem_device->state = MEMORY_POWER_OFF_STATE;
278         return result;
279 }
280
281 static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
282 {
283         struct acpi_memory_device *mem_device;
284         struct acpi_device *device;
285
286         ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
287
288         switch (event) {
289         case ACPI_NOTIFY_BUS_CHECK:
290                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
291                                   "\nReceived BUS CHECK notification for device\n"));
292                 /* Fall Through */
293         case ACPI_NOTIFY_DEVICE_CHECK:
294                 if (event == ACPI_NOTIFY_DEVICE_CHECK)
295                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
296                                           "\nReceived DEVICE CHECK notification for device\n"));
297                 if (acpi_memory_get_device(handle, &mem_device)) {
298                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
299                                           "Error in finding driver data\n"));
300                         return_VOID;
301                 }
302
303                 if (!acpi_memory_check_device(mem_device)) {
304                         if (acpi_memory_enable_device(mem_device))
305                                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
306                                                   "Error in acpi_memory_enable_device\n"));
307                 }
308                 break;
309         case ACPI_NOTIFY_EJECT_REQUEST:
310                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
311                                   "\nReceived EJECT REQUEST notification for device\n"));
312
313                 if (acpi_bus_get_device(handle, &device)) {
314                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
315                                           "Device doesn't exist\n"));
316                         break;
317                 }
318                 mem_device = acpi_driver_data(device);
319                 if (!mem_device) {
320                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
321                                           "Driver Data is NULL\n"));
322                         break;
323                 }
324
325                 /*
326                  * Currently disabling memory device from kernel mode
327                  * TBD: Can also be disabled from user mode scripts
328                  * TBD: Can also be disabled by Callback registration
329                  *      with generic sysfs driver
330                  */
331                 if (acpi_memory_disable_device(mem_device))
332                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
333                                           "Error in acpi_memory_disable_device\n"));
334                 /*
335                  * TBD: Invoke acpi_bus_remove to cleanup data structures
336                  */
337                 break;
338         default:
339                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
340                                   "Unsupported event [0x%x]\n", event));
341                 break;
342         }
343
344         return_VOID;
345 }
346
347 static int acpi_memory_device_add(struct acpi_device *device)
348 {
349         int result;
350         struct acpi_memory_device *mem_device = NULL;
351
352         ACPI_FUNCTION_TRACE("acpi_memory_device_add");
353
354         if (!device)
355                 return_VALUE(-EINVAL);
356
357         mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
358         if (!mem_device)
359                 return_VALUE(-ENOMEM);
360         memset(mem_device, 0, sizeof(struct acpi_memory_device));
361
362         mem_device->handle = device->handle;
363         sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
364         sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
365         acpi_driver_data(device) = mem_device;
366
367         /* Get the range from the _CRS */
368         result = acpi_memory_get_device_resources(mem_device);
369         if (result) {
370                 kfree(mem_device);
371                 return_VALUE(result);
372         }
373
374         /* Set the device state */
375         mem_device->state = MEMORY_POWER_ON_STATE;
376
377         printk(KERN_INFO "%s \n", acpi_device_name(device));
378
379         return_VALUE(result);
380 }
381
382 static int acpi_memory_device_remove(struct acpi_device *device, int type)
383 {
384         struct acpi_memory_device *mem_device = NULL;
385
386         ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
387
388         if (!device || !acpi_driver_data(device))
389                 return_VALUE(-EINVAL);
390
391         mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
392         kfree(mem_device);
393
394         return_VALUE(0);
395 }
396
397 /*
398  * Helper function to check for memory device
399  */
400 static acpi_status is_memory_device(acpi_handle handle)
401 {
402         char *hardware_id;
403         acpi_status status;
404         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
405         struct acpi_device_info *info;
406
407         ACPI_FUNCTION_TRACE("is_memory_device");
408
409         status = acpi_get_object_info(handle, &buffer);
410         if (ACPI_FAILURE(status))
411                 return_ACPI_STATUS(AE_ERROR);
412
413         info = buffer.pointer;
414         if (!(info->valid & ACPI_VALID_HID)) {
415                 acpi_os_free(buffer.pointer);
416                 return_ACPI_STATUS(AE_ERROR);
417         }
418
419         hardware_id = info->hardware_id.value;
420         if ((hardware_id == NULL) ||
421             (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
422                 status = AE_ERROR;
423
424         acpi_os_free(buffer.pointer);
425         return_ACPI_STATUS(status);
426 }
427
428 static acpi_status
429 acpi_memory_register_notify_handler(acpi_handle handle,
430                                     u32 level, void *ctxt, void **retv)
431 {
432         acpi_status status;
433
434         ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
435
436         status = is_memory_device(handle);
437         if (ACPI_FAILURE(status))
438                 return_ACPI_STATUS(AE_OK);      /* continue */
439
440         status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
441                                              acpi_memory_device_notify, NULL);
442         if (ACPI_FAILURE(status)) {
443                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
444                                   "Error installing notify handler\n"));
445                 return_ACPI_STATUS(AE_OK);      /* continue */
446         }
447
448         return_ACPI_STATUS(status);
449 }
450
451 static acpi_status
452 acpi_memory_deregister_notify_handler(acpi_handle handle,
453                                       u32 level, void *ctxt, void **retv)
454 {
455         acpi_status status;
456
457         ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
458
459         status = is_memory_device(handle);
460         if (ACPI_FAILURE(status))
461                 return_ACPI_STATUS(AE_OK);      /* continue */
462
463         status = acpi_remove_notify_handler(handle,
464                                             ACPI_SYSTEM_NOTIFY,
465                                             acpi_memory_device_notify);
466         if (ACPI_FAILURE(status)) {
467                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
468                                   "Error removing notify handler\n"));
469                 return_ACPI_STATUS(AE_OK);      /* continue */
470         }
471
472         return_ACPI_STATUS(status);
473 }
474
475 static int __init acpi_memory_device_init(void)
476 {
477         int result;
478         acpi_status status;
479
480         ACPI_FUNCTION_TRACE("acpi_memory_device_init");
481
482         result = acpi_bus_register_driver(&acpi_memory_device_driver);
483
484         if (result < 0)
485                 return_VALUE(-ENODEV);
486
487         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
488                                      ACPI_UINT32_MAX,
489                                      acpi_memory_register_notify_handler,
490                                      NULL, NULL);
491
492         if (ACPI_FAILURE(status)) {
493                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
494                 acpi_bus_unregister_driver(&acpi_memory_device_driver);
495                 return_VALUE(-ENODEV);
496         }
497
498         return_VALUE(0);
499 }
500
501 static void __exit acpi_memory_device_exit(void)
502 {
503         acpi_status status;
504
505         ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
506
507         /*
508          * Adding this to un-install notification handlers for all the device
509          * handles.
510          */
511         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
512                                      ACPI_UINT32_MAX,
513                                      acpi_memory_deregister_notify_handler,
514                                      NULL, NULL);
515
516         if (ACPI_FAILURE(status))
517                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
518
519         acpi_bus_unregister_driver(&acpi_memory_device_driver);
520
521         return_VOID;
522 }
523
524 module_init(acpi_memory_device_init);
525 module_exit(acpi_memory_device_exit);