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 */

  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 */