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
 
 
 
 
 
 
 
 25static const struct acpi_device_id memory_device_ids[] = {
 26	{ACPI_MEMORY_DEVICE_HID, 0},
 27	{"", 0},
 28};
 29
 30#ifdef CONFIG_ACPI_HOTPLUG_MEMORY
 31
 
 
 
 
 
 32static int acpi_memory_device_add(struct acpi_device *device,
 33				  const struct acpi_device_id *not_used);
 34static void acpi_memory_device_remove(struct acpi_device *device);
 35
 36static struct acpi_scan_handler memory_device_handler = {
 37	.ids = memory_device_ids,
 38	.attach = acpi_memory_device_add,
 39	.detach = acpi_memory_device_remove,
 40	.hotplug = {
 41		.enabled = true,
 42	},
 43};
 44
 45struct acpi_memory_info {
 46	struct list_head list;
 47	u64 start_addr;		/* Memory Range start physical addr */
 48	u64 length;		/* Memory Range length */
 49	unsigned short caching;	/* memory cache attribute */
 50	unsigned short write_protect;	/* memory read/write attribute */
 51	unsigned int enabled:1;
 52};
 53
 54struct acpi_memory_device {
 55	struct acpi_device *device;
 
 56	struct list_head res_list;
 57	int mgid;
 58};
 59
 60static acpi_status
 61acpi_memory_get_resource(struct acpi_resource *resource, void *context)
 62{
 63	struct acpi_memory_device *mem_device = context;
 64	struct acpi_resource_address64 address64;
 65	struct acpi_memory_info *info, *new;
 66	acpi_status status;
 67
 68	status = acpi_resource_to_address64(resource, &address64);
 69	if (ACPI_FAILURE(status) ||
 70	    (address64.resource_type != ACPI_MEMORY_RANGE))
 71		return AE_OK;
 72
 73	list_for_each_entry(info, &mem_device->res_list, list) {
 74		/* Can we combine the resource range information? */
 75		if ((info->caching == address64.info.mem.caching) &&
 76		    (info->write_protect == address64.info.mem.write_protect) &&
 77		    (info->start_addr + info->length == address64.address.minimum)) {
 78			info->length += address64.address.address_length;
 79			return AE_OK;
 80		}
 81	}
 82
 83	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
 84	if (!new)
 85		return AE_ERROR;
 86
 87	INIT_LIST_HEAD(&new->list);
 88	new->caching = address64.info.mem.caching;
 89	new->write_protect = address64.info.mem.write_protect;
 90	new->start_addr = address64.address.minimum;
 91	new->length = address64.address.address_length;
 92	list_add_tail(&new->list, &mem_device->res_list);
 93
 94	return AE_OK;
 95}
 96
 97static void
 98acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
 99{
100	struct acpi_memory_info *info, *n;
101
102	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
103		kfree(info);
104	INIT_LIST_HEAD(&mem_device->res_list);
105}
106
107static int
108acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
109{
110	acpi_status status;
111
112	if (!list_empty(&mem_device->res_list))
113		return 0;
114
115	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
116				     acpi_memory_get_resource, mem_device);
117	if (ACPI_FAILURE(status)) {
118		acpi_memory_free_device_resources(mem_device);
119		return -EINVAL;
120	}
121
122	return 0;
123}
124
125static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
126{
127	unsigned long long current_status;
128
129	/* Get device present/absent information from the _STA */
130	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle,
131					       METHOD_NAME__STA, NULL,
132					       &current_status)))
133		return -ENODEV;
134	/*
135	 * Check for device status. Device should be
136	 * present/enabled/functioning.
137	 */
138	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
139	      && (current_status & ACPI_STA_DEVICE_ENABLED)
140	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
141		return -ENODEV;
142
143	return 0;
144}
145
 
 
 
 
 
 
 
 
 
 
146static int acpi_bind_memblk(struct memory_block *mem, void *arg)
147{
148	return acpi_bind_one(&mem->dev, arg);
149}
150
151static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
152				   struct acpi_device *adev)
153{
154	return walk_memory_blocks(info->start_addr, info->length, adev,
155				  acpi_bind_memblk);
 
156}
157
158static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
159{
160	acpi_unbind_one(&mem->dev);
161	return 0;
162}
163
164static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
165{
166	walk_memory_blocks(info->start_addr, info->length, NULL,
167			   acpi_unbind_memblk);
168}
169
170static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
171{
172	acpi_handle handle = mem_device->device->handle;
173	mhp_t mhp_flags = MHP_NID_IS_MGID;
174	int result, num_enabled = 0;
175	struct acpi_memory_info *info;
176	u64 total_length = 0;
177	int node, mgid;
178
179	node = acpi_get_node(handle);
180
181	list_for_each_entry(info, &mem_device->res_list, list) {
182		if (!info->length)
183			continue;
184		/* We want a single node for the whole memory group */
185		if (node < 0)
186			node = memory_add_physaddr_to_nid(info->start_addr);
187		total_length += info->length;
188	}
189
190	if (!total_length) {
191		dev_err(&mem_device->device->dev, "device is empty\n");
192		return -EINVAL;
193	}
194
195	mgid = memory_group_register_static(node, PFN_UP(total_length));
196	if (mgid < 0)
197		return mgid;
198	mem_device->mgid = mgid;
199
200	/*
201	 * Tell the VM there is more memory here...
202	 * Note: Assume that this function returns zero on success
203	 * We don't have memory-hot-add rollback function,now.
204	 * (i.e. memory-hot-remove function)
205	 */
206	list_for_each_entry(info, &mem_device->res_list, list) {
 
 
 
 
207		/*
208		 * If the memory block size is zero, please ignore it.
209		 * Don't try to do the following memory hotplug flowchart.
210		 */
211		if (!info->length)
212			continue;
 
 
213
214		mhp_flags |= MHP_MEMMAP_ON_MEMORY;
215		result = __add_memory(mgid, info->start_addr, info->length,
216				      mhp_flags);
217
218		/*
219		 * If the memory block has been used by the kernel, add_memory()
220		 * returns -EEXIST. If add_memory() returns the other error, it
221		 * means that this memory block is not used by the kernel.
222		 */
223		if (result && result != -EEXIST)
224			continue;
225
226		result = acpi_bind_memory_blocks(info, mem_device->device);
227		if (result) {
228			acpi_unbind_memory_blocks(info);
229			return -ENODEV;
230		}
231
232		info->enabled = 1;
233
234		/*
235		 * Add num_enable even if add_memory() returns -EEXIST, so the
236		 * device is bound to this driver.
237		 */
238		num_enabled++;
239	}
240	if (!num_enabled) {
241		dev_err(&mem_device->device->dev, "add_memory failed\n");
 
242		return -EINVAL;
243	}
244	/*
245	 * Sometimes the memory device will contain several memory blocks.
246	 * When one memory block is hot-added to the system memory, it will
247	 * be regarded as a success.
248	 * Otherwise if the last memory block can't be hot-added to the system
249	 * memory, it will be failure and the memory device can't be bound with
250	 * driver.
251	 */
252	return 0;
253}
254
255static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
256{
 
257	struct acpi_memory_info *info, *n;
 
258
259	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
260		if (!info->enabled)
261			continue;
262
 
 
 
263		acpi_unbind_memory_blocks(info);
264		__remove_memory(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	/* In case we succeeded adding *some* memory, unregistering fails. */
276	if (mem_device->mgid >= 0)
277		memory_group_unregister(mem_device->mgid);
278
279	acpi_memory_free_device_resources(mem_device);
280	mem_device->device->driver_data = NULL;
281	kfree(mem_device);
282}
283
284static int acpi_memory_device_add(struct acpi_device *device,
285				  const struct acpi_device_id *not_used)
286{
287	struct acpi_memory_device *mem_device;
288	int result;
289
290	if (!device)
291		return -EINVAL;
292
293	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
294	if (!mem_device)
295		return -ENOMEM;
296
297	INIT_LIST_HEAD(&mem_device->res_list);
298	mem_device->device = device;
299	mem_device->mgid = -1;
300	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
301	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
302	device->driver_data = mem_device;
303
304	/* Get the range from the _CRS */
305	result = acpi_memory_get_device_resources(mem_device);
306	if (result) {
307		device->driver_data = NULL;
308		kfree(mem_device);
309		return result;
310	}
 
 
 
311
312	result = acpi_memory_check_device(mem_device);
313	if (result) {
314		acpi_memory_device_free(mem_device);
315		return 0;
316	}
317
318	result = acpi_memory_enable_device(mem_device);
319	if (result) {
320		dev_err(&device->dev, "acpi_memory_enable_device() error\n");
321		acpi_memory_device_free(mem_device);
322		return result;
323	}
324
325	dev_dbg(&device->dev, "Memory device configured by ACPI\n");
326	return 1;
327}
328
329static void acpi_memory_device_remove(struct acpi_device *device)
330{
331	struct acpi_memory_device *mem_device;
332
333	if (!device || !acpi_driver_data(device))
334		return;
335
336	mem_device = acpi_driver_data(device);
337	acpi_memory_remove_memory(mem_device);
338	acpi_memory_device_free(mem_device);
339}
340
341static bool __initdata acpi_no_memhotplug;
342
343void __init acpi_memory_hotplug_init(void)
344{
345	if (acpi_no_memhotplug) {
346		memory_device_handler.attach = NULL;
347		acpi_scan_add_handler(&memory_device_handler);
348		return;
349	}
350	acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
351}
352
353static int __init disable_acpi_memory_hotplug(char *str)
354{
355	acpi_no_memhotplug = true;
356	return 1;
357}
358__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);
359
360#else
361
362static struct acpi_scan_handler memory_device_handler = {
363	.ids = memory_device_ids,
364};
365
366void __init acpi_memory_hotplug_init(void)
367{
368	acpi_scan_add_handler(&memory_device_handler);
369}
370
371#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */

 
  1/*
  2 * Copyright (C) 2004, 2013 Intel Corporation
  3 * Author: Naveen B S <naveen.b.s@intel.com>
  4 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  5 *
  6 * All rights reserved.
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License as published by
 10 * the Free Software Foundation; either version 2 of the License, or (at
 11 * your option) any later version.
 12 *
 13 * This program is distributed in the hope that it will be useful, but
 14 * WITHOUT ANY WARRANTY; without even the implied warranty of
 15 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 16 * NON INFRINGEMENT.  See the GNU General Public License for more
 17 * details.
 18 *
 19 * ACPI based HotPlug driver that supports Memory Hotplug
 20 * This driver fields notifications from firmware for memory add
 21 * and remove operations and alerts the VM of the affected memory
 22 * ranges.
 23 */
 24
 25#include <linux/acpi.h>
 26#include <linux/memory.h>
 27#include <linux/memory_hotplug.h>
 28
 29#include "internal.h"
 30
 31#define ACPI_MEMORY_DEVICE_CLASS		"memory"
 32#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
 33#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"
 34
 35#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT
 36
 37#undef PREFIX
 38#define 	PREFIX		"ACPI:memory_hp:"
 39
 40ACPI_MODULE_NAME("acpi_memhotplug");
 41
 42static const struct acpi_device_id memory_device_ids[] = {
 43	{ACPI_MEMORY_DEVICE_HID, 0},
 44	{"", 0},
 45};
 46
 47#ifdef CONFIG_ACPI_HOTPLUG_MEMORY
 48
 49/* Memory Device States */
 50#define MEMORY_INVALID_STATE	0
 51#define MEMORY_POWER_ON_STATE	1
 52#define MEMORY_POWER_OFF_STATE	2
 53
 54static int acpi_memory_device_add(struct acpi_device *device,
 55				  const struct acpi_device_id *not_used);
 56static void acpi_memory_device_remove(struct acpi_device *device);
 57
 58static struct acpi_scan_handler memory_device_handler = {
 59	.ids = memory_device_ids,
 60	.attach = acpi_memory_device_add,
 61	.detach = acpi_memory_device_remove,
 62	.hotplug = {
 63		.enabled = true,
 64	},
 65};
 66
 67struct acpi_memory_info {
 68	struct list_head list;
 69	u64 start_addr;		/* Memory Range start physical addr */
 70	u64 length;		/* Memory Range length */
 71	unsigned short caching;	/* memory cache attribute */
 72	unsigned short write_protect;	/* memory read/write attribute */
 73	unsigned int enabled:1;
 74};
 75
 76struct acpi_memory_device {
 77	struct acpi_device * device;
 78	unsigned int state;	/* State of the memory device */
 79	struct list_head res_list;
 
 80};
 81
 82static acpi_status
 83acpi_memory_get_resource(struct acpi_resource *resource, void *context)
 84{
 85	struct acpi_memory_device *mem_device = context;
 86	struct acpi_resource_address64 address64;
 87	struct acpi_memory_info *info, *new;
 88	acpi_status status;
 89
 90	status = acpi_resource_to_address64(resource, &address64);
 91	if (ACPI_FAILURE(status) ||
 92	    (address64.resource_type != ACPI_MEMORY_RANGE))
 93		return AE_OK;
 94
 95	list_for_each_entry(info, &mem_device->res_list, list) {
 96		/* Can we combine the resource range information? */
 97		if ((info->caching == address64.info.mem.caching) &&
 98		    (info->write_protect == address64.info.mem.write_protect) &&
 99		    (info->start_addr + info->length == address64.address.minimum)) {
100			info->length += address64.address.address_length;
101			return AE_OK;
102		}
103	}
104
105	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
106	if (!new)
107		return AE_ERROR;
108
109	INIT_LIST_HEAD(&new->list);
110	new->caching = address64.info.mem.caching;
111	new->write_protect = address64.info.mem.write_protect;
112	new->start_addr = address64.address.minimum;
113	new->length = address64.address.address_length;
114	list_add_tail(&new->list, &mem_device->res_list);
115
116	return AE_OK;
117}
118
119static void
120acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
121{
122	struct acpi_memory_info *info, *n;
123
124	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
125		kfree(info);
126	INIT_LIST_HEAD(&mem_device->res_list);
127}
128
129static int
130acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
131{
132	acpi_status status;
133
134	if (!list_empty(&mem_device->res_list))
135		return 0;
136
137	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
138				     acpi_memory_get_resource, mem_device);
139	if (ACPI_FAILURE(status)) {
140		acpi_memory_free_device_resources(mem_device);
141		return -EINVAL;
142	}
143
144	return 0;
145}
146
147static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
148{
149	unsigned long long current_status;
150
151	/* Get device present/absent information from the _STA */
152	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle,
153					       METHOD_NAME__STA, NULL,
154					       &current_status)))
155		return -ENODEV;
156	/*
157	 * Check for device status. Device should be
158	 * present/enabled/functioning.
159	 */
160	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
161	      && (current_status & ACPI_STA_DEVICE_ENABLED)
162	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
163		return -ENODEV;
164
165	return 0;
166}
167
168static unsigned long acpi_meminfo_start_pfn(struct acpi_memory_info *info)
169{
170	return PFN_DOWN(info->start_addr);
171}
172
173static unsigned long acpi_meminfo_end_pfn(struct acpi_memory_info *info)
174{
175	return PFN_UP(info->start_addr + info->length-1);
176}
177
178static int acpi_bind_memblk(struct memory_block *mem, void *arg)
179{
180	return acpi_bind_one(&mem->dev, arg);
181}
182
183static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
184				   struct acpi_device *adev)
185{
186	return walk_memory_range(acpi_meminfo_start_pfn(info),
187				 acpi_meminfo_end_pfn(info), adev,
188				 acpi_bind_memblk);
189}
190
191static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
192{
193	acpi_unbind_one(&mem->dev);
194	return 0;
195}
196
197static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
198{
199	walk_memory_range(acpi_meminfo_start_pfn(info),
200			  acpi_meminfo_end_pfn(info), NULL, acpi_unbind_memblk);
201}
202
203static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
204{
205	acpi_handle handle = mem_device->device->handle;
 
206	int result, num_enabled = 0;
207	struct acpi_memory_info *info;
208	int node;
 
209
210	node = acpi_get_node(handle);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
211	/*
212	 * Tell the VM there is more memory here...
213	 * Note: Assume that this function returns zero on success
214	 * We don't have memory-hot-add rollback function,now.
215	 * (i.e. memory-hot-remove function)
216	 */
217	list_for_each_entry(info, &mem_device->res_list, list) {
218		if (info->enabled) { /* just sanity check...*/
219			num_enabled++;
220			continue;
221		}
222		/*
223		 * If the memory block size is zero, please ignore it.
224		 * Don't try to do the following memory hotplug flowchart.
225		 */
226		if (!info->length)
227			continue;
228		if (node < 0)
229			node = memory_add_physaddr_to_nid(info->start_addr);
230
231		result = add_memory(node, info->start_addr, info->length);
 
 
232
233		/*
234		 * If the memory block has been used by the kernel, add_memory()
235		 * returns -EEXIST. If add_memory() returns the other error, it
236		 * means that this memory block is not used by the kernel.
237		 */
238		if (result && result != -EEXIST)
239			continue;
240
241		result = acpi_bind_memory_blocks(info, mem_device->device);
242		if (result) {
243			acpi_unbind_memory_blocks(info);
244			return -ENODEV;
245		}
246
247		info->enabled = 1;
248
249		/*
250		 * Add num_enable even if add_memory() returns -EEXIST, so the
251		 * device is bound to this driver.
252		 */
253		num_enabled++;
254	}
255	if (!num_enabled) {
256		dev_err(&mem_device->device->dev, "add_memory failed\n");
257		mem_device->state = MEMORY_INVALID_STATE;
258		return -EINVAL;
259	}
260	/*
261	 * Sometimes the memory device will contain several memory blocks.
262	 * When one memory block is hot-added to the system memory, it will
263	 * be regarded as a success.
264	 * Otherwise if the last memory block can't be hot-added to the system
265	 * memory, it will be failure and the memory device can't be bound with
266	 * driver.
267	 */
268	return 0;
269}
270
271static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
272{
273	acpi_handle handle = mem_device->device->handle;
274	struct acpi_memory_info *info, *n;
275	int nid = acpi_get_node(handle);
276
277	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
278		if (!info->enabled)
279			continue;
280
281		if (nid == NUMA_NO_NODE)
282			nid = memory_add_physaddr_to_nid(info->start_addr);
283
284		acpi_unbind_memory_blocks(info);
285		remove_memory(nid, info->start_addr, info->length);
286		list_del(&info->list);
287		kfree(info);
288	}
289}
290
291static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
292{
293	if (!mem_device)
294		return;
295
 
 
 
 
296	acpi_memory_free_device_resources(mem_device);
297	mem_device->device->driver_data = NULL;
298	kfree(mem_device);
299}
300
301static int acpi_memory_device_add(struct acpi_device *device,
302				  const struct acpi_device_id *not_used)
303{
304	struct acpi_memory_device *mem_device;
305	int result;
306
307	if (!device)
308		return -EINVAL;
309
310	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
311	if (!mem_device)
312		return -ENOMEM;
313
314	INIT_LIST_HEAD(&mem_device->res_list);
315	mem_device->device = device;
 
316	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
317	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
318	device->driver_data = mem_device;
319
320	/* Get the range from the _CRS */
321	result = acpi_memory_get_device_resources(mem_device);
322	if (result) {
323		device->driver_data = NULL;
324		kfree(mem_device);
325		return result;
326	}
327
328	/* Set the device state */
329	mem_device->state = MEMORY_POWER_ON_STATE;
330
331	result = acpi_memory_check_device(mem_device);
332	if (result) {
333		acpi_memory_device_free(mem_device);
334		return 0;
335	}
336
337	result = acpi_memory_enable_device(mem_device);
338	if (result) {
339		dev_err(&device->dev, "acpi_memory_enable_device() error\n");
340		acpi_memory_device_free(mem_device);
341		return result;
342	}
343
344	dev_dbg(&device->dev, "Memory device configured by ACPI\n");
345	return 1;
346}
347
348static void acpi_memory_device_remove(struct acpi_device *device)
349{
350	struct acpi_memory_device *mem_device;
351
352	if (!device || !acpi_driver_data(device))
353		return;
354
355	mem_device = acpi_driver_data(device);
356	acpi_memory_remove_memory(mem_device);
357	acpi_memory_device_free(mem_device);
358}
359
360static bool __initdata acpi_no_memhotplug;
361
362void __init acpi_memory_hotplug_init(void)
363{
364	if (acpi_no_memhotplug) {
365		memory_device_handler.attach = NULL;
366		acpi_scan_add_handler(&memory_device_handler);
367		return;
368	}
369	acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
370}
371
372static int __init disable_acpi_memory_hotplug(char *str)
373{
374	acpi_no_memhotplug = true;
375	return 1;
376}
377__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);
378
379#else
380
381static struct acpi_scan_handler memory_device_handler = {
382	.ids = memory_device_ids,
383};
384
385void __init acpi_memory_hotplug_init(void)
386{
387	acpi_scan_add_handler(&memory_device_handler);
388}
389
390#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */