ia64/linux-2.6.18-xen.hg

view drivers/acpi/acpi_memhotplug.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
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 */
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>
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"
41 #define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
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");
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)
53 /* Memory Device States */
54 #define MEMORY_INVALID_STATE 0
55 #define MEMORY_POWER_ON_STATE 1
56 #define MEMORY_POWER_OFF_STATE 2
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 static int acpi_memory_device_start(struct acpi_device *device);
62 static struct acpi_driver acpi_memory_device_driver = {
63 .name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
64 .class = ACPI_MEMORY_DEVICE_CLASS,
65 .ids = ACPI_MEMORY_DEVICE_HID,
66 .ops = {
67 .add = acpi_memory_device_add,
68 .remove = acpi_memory_device_remove,
69 .start = acpi_memory_device_start,
70 },
71 };
73 struct acpi_memory_info {
74 struct list_head list;
75 u64 start_addr; /* Memory Range start physical addr */
76 u64 length; /* Memory Range length */
77 unsigned short caching; /* memory cache attribute */
78 unsigned short write_protect; /* memory read/write attribute */
79 unsigned int enabled:1;
80 };
82 struct acpi_memory_device {
83 struct acpi_device * device;
84 unsigned int state; /* State of the memory device */
85 struct list_head res_list;
86 };
88 static acpi_status
89 acpi_memory_get_resource(struct acpi_resource *resource, void *context)
90 {
91 struct acpi_memory_device *mem_device = context;
92 struct acpi_resource_address64 address64;
93 struct acpi_memory_info *info, *new;
94 acpi_status status;
96 status = acpi_resource_to_address64(resource, &address64);
97 if (ACPI_FAILURE(status) ||
98 (address64.resource_type != ACPI_MEMORY_RANGE))
99 return AE_OK;
101 list_for_each_entry(info, &mem_device->res_list, list) {
102 /* Can we combine the resource range information? */
103 if ((info->caching == address64.info.mem.caching) &&
104 (info->write_protect == address64.info.mem.write_protect) &&
105 (info->start_addr + info->length == address64.minimum)) {
106 info->length += address64.address_length;
107 return AE_OK;
108 }
109 }
111 new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
112 if (!new)
113 return AE_ERROR;
115 INIT_LIST_HEAD(&new->list);
116 new->caching = address64.info.mem.caching;
117 new->write_protect = address64.info.mem.write_protect;
118 new->start_addr = address64.minimum;
119 new->length = address64.address_length;
120 list_add_tail(&new->list, &mem_device->res_list);
122 return AE_OK;
123 }
125 static int
126 acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
127 {
128 acpi_status status;
129 struct acpi_memory_info *info, *n;
132 if (!list_empty(&mem_device->res_list))
133 return 0;
135 status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
136 acpi_memory_get_resource, mem_device);
137 if (ACPI_FAILURE(status)) {
138 list_for_each_entry_safe(info, n, &mem_device->res_list, list)
139 kfree(info);
140 INIT_LIST_HEAD(&mem_device->res_list);
141 return -EINVAL;
142 }
144 return 0;
145 }
147 static int
148 acpi_memory_get_device(acpi_handle handle,
149 struct acpi_memory_device **mem_device)
150 {
151 acpi_status status;
152 acpi_handle phandle;
153 struct acpi_device *device = NULL;
154 struct acpi_device *pdevice = NULL;
157 if (!acpi_bus_get_device(handle, &device) && device)
158 goto end;
160 status = acpi_get_parent(handle, &phandle);
161 if (ACPI_FAILURE(status)) {
162 ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
163 return -EINVAL;
164 }
166 /* Get the parent device */
167 status = acpi_bus_get_device(phandle, &pdevice);
168 if (ACPI_FAILURE(status)) {
169 ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
170 return -EINVAL;
171 }
173 /*
174 * Now add the notified device. This creates the acpi_device
175 * and invokes .add function
176 */
177 status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
178 if (ACPI_FAILURE(status)) {
179 ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
180 return -EINVAL;
181 }
183 end:
184 *mem_device = acpi_driver_data(device);
185 if (!(*mem_device)) {
186 printk(KERN_ERR "\n driver data not found");
187 return -ENODEV;
188 }
190 return 0;
191 }
193 static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
194 {
195 unsigned long current_status;
198 /* Get device present/absent information from the _STA */
199 if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
200 NULL, &current_status)))
201 return -ENODEV;
202 /*
203 * Check for device status. Device should be
204 * present/enabled/functioning.
205 */
206 if (!((current_status & ACPI_MEMORY_STA_PRESENT)
207 && (current_status & ACPI_MEMORY_STA_ENABLED)
208 && (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
209 return -ENODEV;
211 return 0;
212 }
214 static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
215 {
216 int result, num_enabled = 0;
217 struct acpi_memory_info *info;
218 int node;
221 /* Get the range from the _CRS */
222 result = acpi_memory_get_device_resources(mem_device);
223 if (result) {
224 printk(KERN_ERR PREFIX "get_device_resources failed\n");
225 mem_device->state = MEMORY_INVALID_STATE;
226 return result;
227 }
229 node = acpi_get_node(mem_device->device->handle);
230 /*
231 * Tell the VM there is more memory here...
232 * Note: Assume that this function returns zero on success
233 * We don't have memory-hot-add rollback function,now.
234 * (i.e. memory-hot-remove function)
235 */
236 list_for_each_entry(info, &mem_device->res_list, list) {
237 if (info->enabled) { /* just sanity check...*/
238 num_enabled++;
239 continue;
240 }
241 result = add_memory(node, info->start_addr, info->length);
242 if (result)
243 continue;
244 info->enabled = 1;
245 num_enabled++;
246 }
247 if (!num_enabled) {
248 printk(KERN_ERR PREFIX "add_memory failed\n");
249 mem_device->state = MEMORY_INVALID_STATE;
250 return -EINVAL;
251 }
253 return result;
254 }
256 static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
257 {
258 acpi_status status;
259 struct acpi_object_list arg_list;
260 union acpi_object arg;
261 unsigned long current_status;
264 /* Issue the _EJ0 command */
265 arg_list.count = 1;
266 arg_list.pointer = &arg;
267 arg.type = ACPI_TYPE_INTEGER;
268 arg.integer.value = 1;
269 status = acpi_evaluate_object(mem_device->device->handle,
270 "_EJ0", &arg_list, NULL);
271 /* Return on _EJ0 failure */
272 if (ACPI_FAILURE(status)) {
273 ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
274 return -ENODEV;
275 }
277 /* Evalute _STA to check if the device is disabled */
278 status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
279 NULL, &current_status);
280 if (ACPI_FAILURE(status))
281 return -ENODEV;
283 /* Check for device status. Device should be disabled */
284 if (current_status & ACPI_MEMORY_STA_ENABLED)
285 return -EINVAL;
287 return 0;
288 }
290 static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
291 {
292 int result;
293 struct acpi_memory_info *info, *n;
296 /*
297 * Ask the VM to offline this memory range.
298 * Note: Assume that this function returns zero on success
299 */
300 list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
301 if (info->enabled) {
302 result = remove_memory(info->start_addr, info->length);
303 if (result)
304 return result;
305 }
306 kfree(info);
307 }
309 /* Power-off and eject the device */
310 result = acpi_memory_powerdown_device(mem_device);
311 if (result) {
312 /* Set the status of the device to invalid */
313 mem_device->state = MEMORY_INVALID_STATE;
314 return result;
315 }
317 mem_device->state = MEMORY_POWER_OFF_STATE;
318 return result;
319 }
321 static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
322 {
323 struct acpi_memory_device *mem_device;
324 struct acpi_device *device;
327 switch (event) {
328 case ACPI_NOTIFY_BUS_CHECK:
329 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
330 "\nReceived BUS CHECK notification for device\n"));
331 /* Fall Through */
332 case ACPI_NOTIFY_DEVICE_CHECK:
333 if (event == ACPI_NOTIFY_DEVICE_CHECK)
334 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
335 "\nReceived DEVICE CHECK notification for device\n"));
336 if (acpi_memory_get_device(handle, &mem_device)) {
337 printk(KERN_ERR PREFIX "Cannot find driver data\n");
338 return;
339 }
341 if (!acpi_memory_check_device(mem_device)) {
342 if (acpi_memory_enable_device(mem_device))
343 printk(KERN_ERR PREFIX
344 "Cannot enable memory device\n");
345 }
346 break;
347 case ACPI_NOTIFY_EJECT_REQUEST:
348 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
349 "\nReceived EJECT REQUEST notification for device\n"));
351 if (acpi_bus_get_device(handle, &device)) {
352 printk(KERN_ERR PREFIX "Device doesn't exist\n");
353 break;
354 }
355 mem_device = acpi_driver_data(device);
356 if (!mem_device) {
357 printk(KERN_ERR PREFIX "Driver Data is NULL\n");
358 break;
359 }
361 /*
362 * Currently disabling memory device from kernel mode
363 * TBD: Can also be disabled from user mode scripts
364 * TBD: Can also be disabled by Callback registration
365 * with generic sysfs driver
366 */
367 if (acpi_memory_disable_device(mem_device))
368 printk(KERN_ERR PREFIX
369 "Disable memory device\n");
370 /*
371 * TBD: Invoke acpi_bus_remove to cleanup data structures
372 */
373 break;
374 default:
375 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
376 "Unsupported event [0x%x]\n", event));
377 break;
378 }
380 return;
381 }
383 static int acpi_memory_device_add(struct acpi_device *device)
384 {
385 int result;
386 struct acpi_memory_device *mem_device = NULL;
389 if (!device)
390 return -EINVAL;
392 mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
393 if (!mem_device)
394 return -ENOMEM;
395 memset(mem_device, 0, sizeof(struct acpi_memory_device));
397 INIT_LIST_HEAD(&mem_device->res_list);
398 mem_device->device = device;
399 sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
400 sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
401 acpi_driver_data(device) = mem_device;
403 /* Get the range from the _CRS */
404 result = acpi_memory_get_device_resources(mem_device);
405 if (result) {
406 kfree(mem_device);
407 return result;
408 }
410 /* Set the device state */
411 mem_device->state = MEMORY_POWER_ON_STATE;
413 printk(KERN_INFO "%s \n", acpi_device_name(device));
415 return result;
416 }
418 static int acpi_memory_device_remove(struct acpi_device *device, int type)
419 {
420 struct acpi_memory_device *mem_device = NULL;
423 if (!device || !acpi_driver_data(device))
424 return -EINVAL;
426 mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
427 kfree(mem_device);
429 return 0;
430 }
432 static int acpi_memory_device_start (struct acpi_device *device)
433 {
434 struct acpi_memory_device *mem_device;
435 int result = 0;
437 mem_device = acpi_driver_data(device);
439 if (!acpi_memory_check_device(mem_device)) {
440 /* call add_memory func */
441 result = acpi_memory_enable_device(mem_device);
442 if (result)
443 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
444 "Error in acpi_memory_enable_device\n"));
445 }
446 return result;
447 }
449 /*
450 * Helper function to check for memory device
451 */
452 static acpi_status is_memory_device(acpi_handle handle)
453 {
454 char *hardware_id;
455 acpi_status status;
456 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
457 struct acpi_device_info *info;
460 status = acpi_get_object_info(handle, &buffer);
461 if (ACPI_FAILURE(status))
462 return status;
464 info = buffer.pointer;
465 if (!(info->valid & ACPI_VALID_HID)) {
466 kfree(buffer.pointer);
467 return AE_ERROR;
468 }
470 hardware_id = info->hardware_id.value;
471 if ((hardware_id == NULL) ||
472 (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
473 status = AE_ERROR;
475 kfree(buffer.pointer);
476 return status;
477 }
479 static acpi_status
480 acpi_memory_register_notify_handler(acpi_handle handle,
481 u32 level, void *ctxt, void **retv)
482 {
483 acpi_status status;
486 status = is_memory_device(handle);
487 if (ACPI_FAILURE(status))
488 return AE_OK; /* continue */
490 status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
491 acpi_memory_device_notify, NULL);
492 /* continue */
493 return AE_OK;
494 }
496 static acpi_status
497 acpi_memory_deregister_notify_handler(acpi_handle handle,
498 u32 level, void *ctxt, void **retv)
499 {
500 acpi_status status;
503 status = is_memory_device(handle);
504 if (ACPI_FAILURE(status))
505 return AE_OK; /* continue */
507 status = acpi_remove_notify_handler(handle,
508 ACPI_SYSTEM_NOTIFY,
509 acpi_memory_device_notify);
511 return AE_OK; /* continue */
512 }
514 static int __init acpi_memory_device_init(void)
515 {
516 int result;
517 acpi_status status;
520 result = acpi_bus_register_driver(&acpi_memory_device_driver);
522 if (result < 0)
523 return -ENODEV;
525 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
526 ACPI_UINT32_MAX,
527 acpi_memory_register_notify_handler,
528 NULL, NULL);
530 if (ACPI_FAILURE(status)) {
531 ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
532 acpi_bus_unregister_driver(&acpi_memory_device_driver);
533 return -ENODEV;
534 }
536 return 0;
537 }
539 static void __exit acpi_memory_device_exit(void)
540 {
541 acpi_status status;
544 /*
545 * Adding this to un-install notification handlers for all the device
546 * handles.
547 */
548 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
549 ACPI_UINT32_MAX,
550 acpi_memory_deregister_notify_handler,
551 NULL, NULL);
553 if (ACPI_FAILURE(status))
554 ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
556 acpi_bus_unregister_driver(&acpi_memory_device_driver);
558 return;
559 }
561 module_init(acpi_memory_device_init);
562 module_exit(acpi_memory_device_exit);