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v3.1
 
  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 firmware 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 <linux/slab.h>
 34#include <acpi/acpi_drivers.h>
 35
 36#define ACPI_MEMORY_DEVICE_CLASS		"memory"
 37#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
 38#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"
 39
 40#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT
 41
 42#undef PREFIX
 43#define 	PREFIX		"ACPI:memory_hp:"
 44
 45ACPI_MODULE_NAME("acpi_memhotplug");
 46MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
 47MODULE_DESCRIPTION("Hotplug Mem Driver");
 48MODULE_LICENSE("GPL");
 
 
 
 
 49
 50/* Memory Device States */
 51#define MEMORY_INVALID_STATE	0
 52#define MEMORY_POWER_ON_STATE	1
 53#define MEMORY_POWER_OFF_STATE	2
 54
 55static int acpi_memory_device_add(struct acpi_device *device);
 56static int acpi_memory_device_remove(struct acpi_device *device, int type);
 
 57
 58static const struct acpi_device_id memory_device_ids[] = {
 59	{ACPI_MEMORY_DEVICE_HID, 0},
 60	{"", 0},
 61};
 62MODULE_DEVICE_TABLE(acpi, memory_device_ids);
 63
 64static struct acpi_driver acpi_memory_device_driver = {
 65	.name = "acpi_memhotplug",
 66	.class = ACPI_MEMORY_DEVICE_CLASS,
 67	.ids = memory_device_ids,
 68	.ops = {
 69		.add = acpi_memory_device_add,
 70		.remove = acpi_memory_device_remove,
 71		},
 
 72};
 73
 74struct acpi_memory_info {
 75	struct list_head list;
 76	u64 start_addr;		/* Memory Range start physical addr */
 77	u64 length;		/* Memory Range length */
 78	unsigned short caching;	/* memory cache attribute */
 79	unsigned short write_protect;	/* memory read/write attribute */
 80	unsigned int enabled:1;
 81};
 82
 83struct acpi_memory_device {
 84	struct acpi_device * device;
 85	unsigned int state;	/* State of the memory device */
 86	struct list_head res_list;
 87};
 88
 89static int acpi_hotmem_initialized;
 90
 91static acpi_status
 92acpi_memory_get_resource(struct acpi_resource *resource, void *context)
 93{
 94	struct acpi_memory_device *mem_device = context;
 95	struct acpi_resource_address64 address64;
 96	struct acpi_memory_info *info, *new;
 97	acpi_status status;
 98
 99	status = acpi_resource_to_address64(resource, &address64);
100	if (ACPI_FAILURE(status) ||
101	    (address64.resource_type != ACPI_MEMORY_RANGE))
102		return AE_OK;
103
104	list_for_each_entry(info, &mem_device->res_list, list) {
105		/* Can we combine the resource range information? */
106		if ((info->caching == address64.info.mem.caching) &&
107		    (info->write_protect == address64.info.mem.write_protect) &&
108		    (info->start_addr + info->length == address64.minimum)) {
109			info->length += address64.address_length;
110			return AE_OK;
111		}
112	}
113
114	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
115	if (!new)
116		return AE_ERROR;
117
118	INIT_LIST_HEAD(&new->list);
119	new->caching = address64.info.mem.caching;
120	new->write_protect = address64.info.mem.write_protect;
121	new->start_addr = address64.minimum;
122	new->length = address64.address_length;
123	list_add_tail(&new->list, &mem_device->res_list);
124
125	return AE_OK;
126}
127
 
 
 
 
 
 
 
 
 
 
128static int
129acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
130{
131	acpi_status status;
132	struct acpi_memory_info *info, *n;
133
134
135	if (!list_empty(&mem_device->res_list))
136		return 0;
137
138	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
139				     acpi_memory_get_resource, mem_device);
140	if (ACPI_FAILURE(status)) {
141		list_for_each_entry_safe(info, n, &mem_device->res_list, list)
142			kfree(info);
143		INIT_LIST_HEAD(&mem_device->res_list);
144		return -EINVAL;
145	}
146
147	return 0;
148}
149
150static int
151acpi_memory_get_device(acpi_handle handle,
152		       struct acpi_memory_device **mem_device)
153{
154	acpi_status status;
155	acpi_handle phandle;
156	struct acpi_device *device = NULL;
157	struct acpi_device *pdevice = NULL;
158	int result;
159
160
161	if (!acpi_bus_get_device(handle, &device) && device)
162		goto end;
163
164	status = acpi_get_parent(handle, &phandle);
165	if (ACPI_FAILURE(status)) {
166		ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
167		return -EINVAL;
168	}
169
170	/* Get the parent device */
171	result = acpi_bus_get_device(phandle, &pdevice);
172	if (result) {
173		printk(KERN_WARNING PREFIX "Cannot get acpi bus device");
174		return -EINVAL;
175	}
176
177	/*
178	 * Now add the notified device.  This creates the acpi_device
179	 * and invokes .add function
180	 */
181	result = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
182	if (result) {
183		printk(KERN_WARNING PREFIX "Cannot add acpi bus");
184		return -EINVAL;
185	}
186
187      end:
188	*mem_device = acpi_driver_data(device);
189	if (!(*mem_device)) {
190		printk(KERN_ERR "\n driver data not found");
191		return -ENODEV;
192	}
193
194	return 0;
195}
196
197static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
198{
199	unsigned long long current_status;
200
201	/* Get device present/absent information from the _STA */
202	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
203					       NULL, &current_status)))
 
204		return -ENODEV;
205	/*
206	 * Check for device status. Device should be
207	 * present/enabled/functioning.
208	 */
209	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
210	      && (current_status & ACPI_STA_DEVICE_ENABLED)
211	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
212		return -ENODEV;
213
214	return 0;
215}
216
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
217static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
218{
 
219	int result, num_enabled = 0;
220	struct acpi_memory_info *info;
221	int node;
222
223
224	/* Get the range from the _CRS */
225	result = acpi_memory_get_device_resources(mem_device);
226	if (result) {
227		printk(KERN_ERR PREFIX "get_device_resources failed\n");
228		mem_device->state = MEMORY_INVALID_STATE;
229		return result;
230	}
231
232	node = acpi_get_node(mem_device->device->handle);
233	/*
234	 * Tell the VM there is more memory here...
235	 * Note: Assume that this function returns zero on success
236	 * We don't have memory-hot-add rollback function,now.
237	 * (i.e. memory-hot-remove function)
238	 */
239	list_for_each_entry(info, &mem_device->res_list, list) {
240		if (info->enabled) { /* just sanity check...*/
241			num_enabled++;
242			continue;
243		}
244		/*
245		 * If the memory block size is zero, please ignore it.
246		 * Don't try to do the following memory hotplug flowchart.
247		 */
248		if (!info->length)
249			continue;
250		if (node < 0)
251			node = memory_add_physaddr_to_nid(info->start_addr);
252
253		result = add_memory(node, info->start_addr, info->length);
254		if (result)
 
 
 
 
 
 
255			continue;
 
 
 
 
 
 
 
256		info->enabled = 1;
 
 
 
 
 
257		num_enabled++;
258	}
259	if (!num_enabled) {
260		printk(KERN_ERR PREFIX "add_memory failed\n");
261		mem_device->state = MEMORY_INVALID_STATE;
262		return -EINVAL;
263	}
264	/*
265	 * Sometimes the memory device will contain several memory blocks.
266	 * When one memory block is hot-added to the system memory, it will
267	 * be regarded as a success.
268	 * Otherwise if the last memory block can't be hot-added to the system
269	 * memory, it will be failure and the memory device can't be bound with
270	 * driver.
271	 */
272	return 0;
273}
274
275static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
276{
277	acpi_status status;
278	struct acpi_object_list arg_list;
279	union acpi_object arg;
280	unsigned long long current_status;
281
282
283	/* Issue the _EJ0 command */
284	arg_list.count = 1;
285	arg_list.pointer = &arg;
286	arg.type = ACPI_TYPE_INTEGER;
287	arg.integer.value = 1;
288	status = acpi_evaluate_object(mem_device->device->handle,
289				      "_EJ0", &arg_list, NULL);
290	/* Return on _EJ0 failure */
291	if (ACPI_FAILURE(status)) {
292		ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
293		return -ENODEV;
294	}
295
296	/* Evalute _STA to check if the device is disabled */
297	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
298				       NULL, &current_status);
299	if (ACPI_FAILURE(status))
300		return -ENODEV;
301
302	/* Check for device status.  Device should be disabled */
303	if (current_status & ACPI_STA_DEVICE_ENABLED)
304		return -EINVAL;
305
306	return 0;
307}
308
309static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
310{
311	int result;
312	struct acpi_memory_info *info, *n;
 
313
314
315	/*
316	 * Ask the VM to offline this memory range.
317	 * Note: Assume that this function returns zero on success
318	 */
319	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
320		if (info->enabled) {
321			result = remove_memory(info->start_addr, info->length);
322			if (result)
323				return result;
324		}
325		kfree(info);
326	}
327
328	/* Power-off and eject the device */
329	result = acpi_memory_powerdown_device(mem_device);
330	if (result) {
331		/* Set the status of the device to invalid */
332		mem_device->state = MEMORY_INVALID_STATE;
333		return result;
334	}
335
336	mem_device->state = MEMORY_POWER_OFF_STATE;
337	return result;
 
 
 
338}
339
340static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
341{
342	struct acpi_memory_device *mem_device;
343	struct acpi_device *device;
344
345
346	switch (event) {
347	case ACPI_NOTIFY_BUS_CHECK:
348		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
349				  "\nReceived BUS CHECK notification for device\n"));
350		/* Fall Through */
351	case ACPI_NOTIFY_DEVICE_CHECK:
352		if (event == ACPI_NOTIFY_DEVICE_CHECK)
353			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
354					  "\nReceived DEVICE CHECK notification for device\n"));
355		if (acpi_memory_get_device(handle, &mem_device)) {
356			printk(KERN_ERR PREFIX "Cannot find driver data\n");
357			return;
358		}
359
360		if (!acpi_memory_check_device(mem_device)) {
361			if (acpi_memory_enable_device(mem_device))
362				printk(KERN_ERR PREFIX
363					    "Cannot enable memory device\n");
364		}
365		break;
366	case ACPI_NOTIFY_EJECT_REQUEST:
367		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
368				  "\nReceived EJECT REQUEST notification for device\n"));
369
370		if (acpi_bus_get_device(handle, &device)) {
371			printk(KERN_ERR PREFIX "Device doesn't exist\n");
372			break;
373		}
374		mem_device = acpi_driver_data(device);
375		if (!mem_device) {
376			printk(KERN_ERR PREFIX "Driver Data is NULL\n");
377			break;
378		}
379
380		/*
381		 * Currently disabling memory device from kernel mode
382		 * TBD: Can also be disabled from user mode scripts
383		 * TBD: Can also be disabled by Callback registration
384		 *      with generic sysfs driver
385		 */
386		if (acpi_memory_disable_device(mem_device))
387			printk(KERN_ERR PREFIX
388				    "Disable memory device\n");
389		/*
390		 * TBD: Invoke acpi_bus_remove to cleanup data structures
391		 */
392		break;
393	default:
394		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
395				  "Unsupported event [0x%x]\n", event));
396		break;
397	}
398
399	return;
 
 
400}
401
402static int acpi_memory_device_add(struct acpi_device *device)
 
403{
 
404	int result;
405	struct acpi_memory_device *mem_device = NULL;
406
407
408	if (!device)
409		return -EINVAL;
410
411	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
412	if (!mem_device)
413		return -ENOMEM;
414
415	INIT_LIST_HEAD(&mem_device->res_list);
416	mem_device->device = device;
417	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
418	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
419	device->driver_data = mem_device;
420
421	/* Get the range from the _CRS */
422	result = acpi_memory_get_device_resources(mem_device);
423	if (result) {
 
424		kfree(mem_device);
425		return result;
426	}
427
428	/* Set the device state */
429	mem_device->state = MEMORY_POWER_ON_STATE;
430
431	printk(KERN_DEBUG "%s \n", acpi_device_name(device));
432
433	/*
434	 * Early boot code has recognized memory area by EFI/E820.
435	 * If DSDT shows these memory devices on boot, hotplug is not necessary
436	 * for them. So, it just returns until completion of this driver's
437	 * start up.
438	 */
439	if (!acpi_hotmem_initialized)
440		return 0;
 
441
442	if (!acpi_memory_check_device(mem_device)) {
443		/* call add_memory func */
444		result = acpi_memory_enable_device(mem_device);
445		if (result)
446			printk(KERN_ERR PREFIX
447				"Error in acpi_memory_enable_device\n");
448	}
449	return result;
 
 
450}
451
452static int acpi_memory_device_remove(struct acpi_device *device, int type)
453{
454	struct acpi_memory_device *mem_device = NULL;
455
456
457	if (!device || !acpi_driver_data(device))
458		return -EINVAL;
459
460	mem_device = acpi_driver_data(device);
461	kfree(mem_device);
462
463	return 0;
464}
465
466/*
467 * Helper function to check for memory device
468 */
469static acpi_status is_memory_device(acpi_handle handle)
470{
471	char *hardware_id;
472	acpi_status status;
473	struct acpi_device_info *info;
474
475	status = acpi_get_object_info(handle, &info);
476	if (ACPI_FAILURE(status))
477		return status;
478
479	if (!(info->valid & ACPI_VALID_HID)) {
480		kfree(info);
481		return AE_ERROR;
482	}
483
484	hardware_id = info->hardware_id.string;
485	if ((hardware_id == NULL) ||
486	    (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
487		status = AE_ERROR;
488
489	kfree(info);
490	return status;
491}
492
493static acpi_status
494acpi_memory_register_notify_handler(acpi_handle handle,
495				    u32 level, void *ctxt, void **retv)
496{
497	acpi_status status;
498
499
500	status = is_memory_device(handle);
501	if (ACPI_FAILURE(status))
502		return AE_OK;	/* continue */
503
504	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
505					     acpi_memory_device_notify, NULL);
506	/* continue */
507	return AE_OK;
508}
509
510static acpi_status
511acpi_memory_deregister_notify_handler(acpi_handle handle,
512				      u32 level, void *ctxt, void **retv)
513{
514	acpi_status status;
515
516
517	status = is_memory_device(handle);
518	if (ACPI_FAILURE(status))
519		return AE_OK;	/* continue */
520
521	status = acpi_remove_notify_handler(handle,
522					    ACPI_SYSTEM_NOTIFY,
523					    acpi_memory_device_notify);
524
525	return AE_OK;	/* continue */
526}
 
527
528static int __init acpi_memory_device_init(void)
529{
530	int result;
531	acpi_status status;
532
533
534	result = acpi_bus_register_driver(&acpi_memory_device_driver);
535
536	if (result < 0)
537		return -ENODEV;
538
539	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
540				     ACPI_UINT32_MAX,
541				     acpi_memory_register_notify_handler, NULL,
542				     NULL, NULL);
543
544	if (ACPI_FAILURE(status)) {
545		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
546		acpi_bus_unregister_driver(&acpi_memory_device_driver);
547		return -ENODEV;
548	}
549
550	acpi_hotmem_initialized = 1;
551	return 0;
552}
553
554static void __exit acpi_memory_device_exit(void)
555{
556	acpi_status status;
557
558
559	/*
560	 * Adding this to un-install notification handlers for all the device
561	 * handles.
562	 */
563	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
564				     ACPI_UINT32_MAX,
565				     acpi_memory_deregister_notify_handler, NULL,
566				     NULL, NULL);
567
568	if (ACPI_FAILURE(status))
569		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
570
571	acpi_bus_unregister_driver(&acpi_memory_device_driver);
572
573	return;
574}
575
576module_init(acpi_memory_device_init);
577module_exit(acpi_memory_device_exit);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (C) 2004, 2013 Intel Corporation
  4 * Author: Naveen B S <naveen.b.s@intel.com>
  5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  6 *
  7 * All rights reserved.
  8 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9 * ACPI based HotPlug driver that supports Memory Hotplug
 10 * This driver fields notifications from firmware for memory add
 11 * and remove operations and alerts the VM of the affected memory
 12 * ranges.
 13 */
 14
 15#include <linux/acpi.h>
 16#include <linux/memory.h>
 
 
 17#include <linux/memory_hotplug.h>
 18
 19#include "internal.h"
 20
 21#define ACPI_MEMORY_DEVICE_CLASS		"memory"
 22#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
 23#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"
 24
 25#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT
 26
 27#undef PREFIX
 28#define 	PREFIX		"ACPI:memory_hp:"
 29
 30ACPI_MODULE_NAME("acpi_memhotplug");
 31
 32static const struct acpi_device_id memory_device_ids[] = {
 33	{ACPI_MEMORY_DEVICE_HID, 0},
 34	{"", 0},
 35};
 36
 37#ifdef CONFIG_ACPI_HOTPLUG_MEMORY
 38
 39/* Memory Device States */
 40#define MEMORY_INVALID_STATE	0
 41#define MEMORY_POWER_ON_STATE	1
 42#define MEMORY_POWER_OFF_STATE	2
 43
 44static int acpi_memory_device_add(struct acpi_device *device,
 45				  const struct acpi_device_id *not_used);
 46static void acpi_memory_device_remove(struct acpi_device *device);
 47
 48static struct acpi_scan_handler memory_device_handler = {
 
 
 
 
 
 
 
 
 49	.ids = memory_device_ids,
 50	.attach = acpi_memory_device_add,
 51	.detach = acpi_memory_device_remove,
 52	.hotplug = {
 53		.enabled = true,
 54	},
 55};
 56
 57struct acpi_memory_info {
 58	struct list_head list;
 59	u64 start_addr;		/* Memory Range start physical addr */
 60	u64 length;		/* Memory Range length */
 61	unsigned short caching;	/* memory cache attribute */
 62	unsigned short write_protect;	/* memory read/write attribute */
 63	unsigned int enabled:1;
 64};
 65
 66struct acpi_memory_device {
 67	struct acpi_device * device;
 68	unsigned int state;	/* State of the memory device */
 69	struct list_head res_list;
 70};
 71
 
 
 72static acpi_status
 73acpi_memory_get_resource(struct acpi_resource *resource, void *context)
 74{
 75	struct acpi_memory_device *mem_device = context;
 76	struct acpi_resource_address64 address64;
 77	struct acpi_memory_info *info, *new;
 78	acpi_status status;
 79
 80	status = acpi_resource_to_address64(resource, &address64);
 81	if (ACPI_FAILURE(status) ||
 82	    (address64.resource_type != ACPI_MEMORY_RANGE))
 83		return AE_OK;
 84
 85	list_for_each_entry(info, &mem_device->res_list, list) {
 86		/* Can we combine the resource range information? */
 87		if ((info->caching == address64.info.mem.caching) &&
 88		    (info->write_protect == address64.info.mem.write_protect) &&
 89		    (info->start_addr + info->length == address64.address.minimum)) {
 90			info->length += address64.address.address_length;
 91			return AE_OK;
 92		}
 93	}
 94
 95	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
 96	if (!new)
 97		return AE_ERROR;
 98
 99	INIT_LIST_HEAD(&new->list);
100	new->caching = address64.info.mem.caching;
101	new->write_protect = address64.info.mem.write_protect;
102	new->start_addr = address64.address.minimum;
103	new->length = address64.address.address_length;
104	list_add_tail(&new->list, &mem_device->res_list);
105
106	return AE_OK;
107}
108
109static void
110acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
111{
112	struct acpi_memory_info *info, *n;
113
114	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
115		kfree(info);
116	INIT_LIST_HEAD(&mem_device->res_list);
117}
118
119static int
120acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
121{
122	acpi_status status;
 
 
123
124	if (!list_empty(&mem_device->res_list))
125		return 0;
126
127	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
128				     acpi_memory_get_resource, mem_device);
129	if (ACPI_FAILURE(status)) {
130		acpi_memory_free_device_resources(mem_device);
 
 
131		return -EINVAL;
132	}
133
134	return 0;
135}
136
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
137static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
138{
139	unsigned long long current_status;
140
141	/* Get device present/absent information from the _STA */
142	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle,
143					       METHOD_NAME__STA, NULL,
144					       &current_status)))
145		return -ENODEV;
146	/*
147	 * Check for device status. Device should be
148	 * present/enabled/functioning.
149	 */
150	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
151	      && (current_status & ACPI_STA_DEVICE_ENABLED)
152	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
153		return -ENODEV;
154
155	return 0;
156}
157
158static int acpi_bind_memblk(struct memory_block *mem, void *arg)
159{
160	return acpi_bind_one(&mem->dev, arg);
161}
162
163static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
164				   struct acpi_device *adev)
165{
166	return walk_memory_blocks(info->start_addr, info->length, adev,
167				  acpi_bind_memblk);
168}
169
170static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
171{
172	acpi_unbind_one(&mem->dev);
173	return 0;
174}
175
176static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
177{
178	walk_memory_blocks(info->start_addr, info->length, NULL,
179			   acpi_unbind_memblk);
180}
181
182static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
183{
184	acpi_handle handle = mem_device->device->handle;
185	int result, num_enabled = 0;
186	struct acpi_memory_info *info;
187	int node;
188
189	node = acpi_get_node(handle);
 
 
 
 
 
 
 
 
 
190	/*
191	 * Tell the VM there is more memory here...
192	 * Note: Assume that this function returns zero on success
193	 * We don't have memory-hot-add rollback function,now.
194	 * (i.e. memory-hot-remove function)
195	 */
196	list_for_each_entry(info, &mem_device->res_list, list) {
197		if (info->enabled) { /* just sanity check...*/
198			num_enabled++;
199			continue;
200		}
201		/*
202		 * If the memory block size is zero, please ignore it.
203		 * Don't try to do the following memory hotplug flowchart.
204		 */
205		if (!info->length)
206			continue;
207		if (node < 0)
208			node = memory_add_physaddr_to_nid(info->start_addr);
209
210		result = __add_memory(node, info->start_addr, info->length);
211
212		/*
213		 * If the memory block has been used by the kernel, add_memory()
214		 * returns -EEXIST. If add_memory() returns the other error, it
215		 * means that this memory block is not used by the kernel.
216		 */
217		if (result && result != -EEXIST)
218			continue;
219
220		result = acpi_bind_memory_blocks(info, mem_device->device);
221		if (result) {
222			acpi_unbind_memory_blocks(info);
223			return -ENODEV;
224		}
225
226		info->enabled = 1;
227
228		/*
229		 * Add num_enable even if add_memory() returns -EEXIST, so the
230		 * device is bound to this driver.
231		 */
232		num_enabled++;
233	}
234	if (!num_enabled) {
235		dev_err(&mem_device->device->dev, "add_memory failed\n");
236		mem_device->state = MEMORY_INVALID_STATE;
237		return -EINVAL;
238	}
239	/*
240	 * Sometimes the memory device will contain several memory blocks.
241	 * When one memory block is hot-added to the system memory, it will
242	 * be regarded as a success.
243	 * Otherwise if the last memory block can't be hot-added to the system
244	 * memory, it will be failure and the memory device can't be bound with
245	 * driver.
246	 */
247	return 0;
248}
249
250static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
251{
252	acpi_handle handle = mem_device->device->handle;
253	struct acpi_memory_info *info, *n;
254	int nid = acpi_get_node(handle);
255
 
 
 
 
 
256	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
257		if (!info->enabled)
258			continue;
 
 
 
 
 
259
260		if (nid == NUMA_NO_NODE)
261			nid = memory_add_physaddr_to_nid(info->start_addr);
 
 
 
 
 
262
263		acpi_unbind_memory_blocks(info);
264		__remove_memory(nid, info->start_addr, info->length);
265		list_del(&info->list);
266		kfree(info);
267	}
268}
269
270static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
271{
272	if (!mem_device)
273		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
274
275	acpi_memory_free_device_resources(mem_device);
276	mem_device->device->driver_data = NULL;
277	kfree(mem_device);
278}
279
280static int acpi_memory_device_add(struct acpi_device *device,
281				  const struct acpi_device_id *not_used)
282{
283	struct acpi_memory_device *mem_device;
284	int result;
 
 
285
286	if (!device)
287		return -EINVAL;
288
289	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
290	if (!mem_device)
291		return -ENOMEM;
292
293	INIT_LIST_HEAD(&mem_device->res_list);
294	mem_device->device = device;
295	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
296	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
297	device->driver_data = mem_device;
298
299	/* Get the range from the _CRS */
300	result = acpi_memory_get_device_resources(mem_device);
301	if (result) {
302		device->driver_data = NULL;
303		kfree(mem_device);
304		return result;
305	}
306
307	/* Set the device state */
308	mem_device->state = MEMORY_POWER_ON_STATE;
309
310	result = acpi_memory_check_device(mem_device);
311	if (result) {
312		acpi_memory_device_free(mem_device);
 
 
 
 
 
 
313		return 0;
314	}
315
316	result = acpi_memory_enable_device(mem_device);
317	if (result) {
318		dev_err(&device->dev, "acpi_memory_enable_device() error\n");
319		acpi_memory_device_free(mem_device);
320		return result;
 
321	}
322
323	dev_dbg(&device->dev, "Memory device configured by ACPI\n");
324	return 1;
325}
326
327static void acpi_memory_device_remove(struct acpi_device *device)
328{
329	struct acpi_memory_device *mem_device;
 
330
331	if (!device || !acpi_driver_data(device))
332		return;
333
334	mem_device = acpi_driver_data(device);
335	acpi_memory_remove_memory(mem_device);
336	acpi_memory_device_free(mem_device);
 
337}
338
339static bool __initdata acpi_no_memhotplug;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340
341void __init acpi_memory_hotplug_init(void)
 
 
342{
343	if (acpi_no_memhotplug) {
344		memory_device_handler.attach = NULL;
345		acpi_scan_add_handler(&memory_device_handler);
346		return;
347	}
348	acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
 
 
 
 
 
349}
350
351static int __init disable_acpi_memory_hotplug(char *str)
 
 
352{
353	acpi_no_memhotplug = true;
354	return 1;
 
 
 
 
 
 
 
 
 
 
355}
356__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);
357
358#else
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
359
360static struct acpi_scan_handler memory_device_handler = {
361	.ids = memory_device_ids,
362};
363
364void __init acpi_memory_hotplug_init(void)
365{
366	acpi_scan_add_handler(&memory_device_handler);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
367}
368
369#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */