Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: e294f44a785046656379b574893061c6377b5beb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2004, 2013 Intel Corporation
 * Author: Naveen B S <naveen.b.s@intel.com>
 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 *
 * All rights reserved.
 *
 * ACPI based HotPlug driver that supports Memory Hotplug
 * This driver fields notifications from firmware for memory add
 * and remove operations and alerts the VM of the affected memory
 * ranges.
 */

#include <linux/acpi.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>

#include "internal.h"

#define ACPI_MEMORY_DEVICE_CLASS		"memory"
#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"

#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT

#undef PREFIX
#define 	PREFIX		"ACPI:memory_hp:"

ACPI_MODULE_NAME("acpi_memhotplug");

static const struct acpi_device_id memory_device_ids[] = {
	{ACPI_MEMORY_DEVICE_HID, 0},
	{"", 0},
};

#ifdef CONFIG_ACPI_HOTPLUG_MEMORY

/* Memory Device States */
#define MEMORY_INVALID_STATE	0
#define MEMORY_POWER_ON_STATE	1
#define MEMORY_POWER_OFF_STATE	2

static int acpi_memory_device_add(struct acpi_device *device,
				  const struct acpi_device_id *not_used);
static void acpi_memory_device_remove(struct acpi_device *device);

static struct acpi_scan_handler memory_device_handler = {
	.ids = memory_device_ids,
	.attach = acpi_memory_device_add,
	.detach = acpi_memory_device_remove,
	.hotplug = {
		.enabled = true,
	},
};

struct acpi_memory_info {
	struct list_head list;
	u64 start_addr;		/* Memory Range start physical addr */
	u64 length;		/* Memory Range length */
	unsigned short caching;	/* memory cache attribute */
	unsigned short write_protect;	/* memory read/write attribute */
	unsigned int enabled:1;
};

struct acpi_memory_device {
	struct acpi_device * device;
	unsigned int state;	/* State of the memory device */
	struct list_head res_list;
};

static acpi_status
acpi_memory_get_resource(struct acpi_resource *resource, void *context)
{
	struct acpi_memory_device *mem_device = context;
	struct acpi_resource_address64 address64;
	struct acpi_memory_info *info, *new;
	acpi_status status;

	status = acpi_resource_to_address64(resource, &address64);
	if (ACPI_FAILURE(status) ||
	    (address64.resource_type != ACPI_MEMORY_RANGE))
		return AE_OK;

	list_for_each_entry(info, &mem_device->res_list, list) {
		/* Can we combine the resource range information? */
		if ((info->caching == address64.info.mem.caching) &&
		    (info->write_protect == address64.info.mem.write_protect) &&
		    (info->start_addr + info->length == address64.address.minimum)) {
			info->length += address64.address.address_length;
			return AE_OK;
		}
	}

	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	if (!new)
		return AE_ERROR;

	INIT_LIST_HEAD(&new->list);
	new->caching = address64.info.mem.caching;
	new->write_protect = address64.info.mem.write_protect;
	new->start_addr = address64.address.minimum;
	new->length = address64.address.address_length;
	list_add_tail(&new->list, &mem_device->res_list);

	return AE_OK;
}

static void
acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
{
	struct acpi_memory_info *info, *n;

	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
		kfree(info);
	INIT_LIST_HEAD(&mem_device->res_list);
}

static int
acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
{
	acpi_status status;

	if (!list_empty(&mem_device->res_list))
		return 0;

	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
				     acpi_memory_get_resource, mem_device);
	if (ACPI_FAILURE(status)) {
		acpi_memory_free_device_resources(mem_device);
		return -EINVAL;
	}

	return 0;
}

static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
{
	unsigned long long current_status;

	/* Get device present/absent information from the _STA */
	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle,
					       METHOD_NAME__STA, NULL,
					       &current_status)))
		return -ENODEV;
	/*
	 * Check for device status. Device should be
	 * present/enabled/functioning.
	 */
	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
	      && (current_status & ACPI_STA_DEVICE_ENABLED)
	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
		return -ENODEV;

	return 0;
}

static int acpi_bind_memblk(struct memory_block *mem, void *arg)
{
	return acpi_bind_one(&mem->dev, arg);
}

static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
				   struct acpi_device *adev)
{
	return walk_memory_blocks(info->start_addr, info->length, adev,
				  acpi_bind_memblk);
}

static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
{
	acpi_unbind_one(&mem->dev);
	return 0;
}

static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
{
	walk_memory_blocks(info->start_addr, info->length, NULL,
			   acpi_unbind_memblk);
}

static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
	acpi_handle handle = mem_device->device->handle;
	int result, num_enabled = 0;
	struct acpi_memory_info *info;
	int node;

	node = acpi_get_node(handle);
	/*
	 * Tell the VM there is more memory here...
	 * Note: Assume that this function returns zero on success
	 * We don't have memory-hot-add rollback function,now.
	 * (i.e. memory-hot-remove function)
	 */
	list_for_each_entry(info, &mem_device->res_list, list) {
		if (info->enabled) { /* just sanity check...*/
			num_enabled++;
			continue;
		}
		/*
		 * If the memory block size is zero, please ignore it.
		 * Don't try to do the following memory hotplug flowchart.
		 */
		if (!info->length)
			continue;
		if (node < 0)
			node = memory_add_physaddr_to_nid(info->start_addr);

		result = __add_memory(node, info->start_addr, info->length);

		/*
		 * If the memory block has been used by the kernel, add_memory()
		 * returns -EEXIST. If add_memory() returns the other error, it
		 * means that this memory block is not used by the kernel.
		 */
		if (result && result != -EEXIST)
			continue;

		result = acpi_bind_memory_blocks(info, mem_device->device);
		if (result) {
			acpi_unbind_memory_blocks(info);
			return -ENODEV;
		}

		info->enabled = 1;

		/*
		 * Add num_enable even if add_memory() returns -EEXIST, so the
		 * device is bound to this driver.
		 */
		num_enabled++;
	}
	if (!num_enabled) {
		dev_err(&mem_device->device->dev, "add_memory failed\n");
		mem_device->state = MEMORY_INVALID_STATE;
		return -EINVAL;
	}
	/*
	 * Sometimes the memory device will contain several memory blocks.
	 * When one memory block is hot-added to the system memory, it will
	 * be regarded as a success.
	 * Otherwise if the last memory block can't be hot-added to the system
	 * memory, it will be failure and the memory device can't be bound with
	 * driver.
	 */
	return 0;
}

static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
{
	acpi_handle handle = mem_device->device->handle;
	struct acpi_memory_info *info, *n;
	int nid = acpi_get_node(handle);

	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
		if (!info->enabled)
			continue;

		if (nid == NUMA_NO_NODE)
			nid = memory_add_physaddr_to_nid(info->start_addr);

		acpi_unbind_memory_blocks(info);
		__remove_memory(nid, info->start_addr, info->length);
		list_del(&info->list);
		kfree(info);
	}
}

static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
{
	if (!mem_device)
		return;

	acpi_memory_free_device_resources(mem_device);
	mem_device->device->driver_data = NULL;
	kfree(mem_device);
}

static int acpi_memory_device_add(struct acpi_device *device,
				  const struct acpi_device_id *not_used)
{
	struct acpi_memory_device *mem_device;
	int result;

	if (!device)
		return -EINVAL;

	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	if (!mem_device)
		return -ENOMEM;

	INIT_LIST_HEAD(&mem_device->res_list);
	mem_device->device = device;
	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	device->driver_data = mem_device;

	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		device->driver_data = NULL;
		kfree(mem_device);
		return result;
	}

	/* Set the device state */
	mem_device->state = MEMORY_POWER_ON_STATE;

	result = acpi_memory_check_device(mem_device);
	if (result) {
		acpi_memory_device_free(mem_device);
		return 0;
	}

	result = acpi_memory_enable_device(mem_device);
	if (result) {
		dev_err(&device->dev, "acpi_memory_enable_device() error\n");
		acpi_memory_device_free(mem_device);
		return result;
	}

	dev_dbg(&device->dev, "Memory device configured by ACPI\n");
	return 1;
}

static void acpi_memory_device_remove(struct acpi_device *device)
{
	struct acpi_memory_device *mem_device;

	if (!device || !acpi_driver_data(device))
		return;

	mem_device = acpi_driver_data(device);
	acpi_memory_remove_memory(mem_device);
	acpi_memory_device_free(mem_device);
}

static bool __initdata acpi_no_memhotplug;

void __init acpi_memory_hotplug_init(void)
{
	if (acpi_no_memhotplug) {
		memory_device_handler.attach = NULL;
		acpi_scan_add_handler(&memory_device_handler);
		return;
	}
	acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
}

static int __init disable_acpi_memory_hotplug(char *str)
{
	acpi_no_memhotplug = true;
	return 1;
}
__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);

#else

static struct acpi_scan_handler memory_device_handler = {
	.ids = memory_device_ids,
};

void __init acpi_memory_hotplug_init(void)
{
	acpi_scan_add_handler(&memory_device_handler);
}

#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */