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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, ¤t_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, ¤t_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);
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 ¤t_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 if (mhp_supports_memmap_on_memory(info->length))
215 mhp_flags |= MHP_MEMMAP_ON_MEMORY;
216 result = __add_memory(mgid, info->start_addr, info->length,
217 mhp_flags);
218
219 /*
220 * If the memory block has been used by the kernel, add_memory()
221 * returns -EEXIST. If add_memory() returns the other error, it
222 * means that this memory block is not used by the kernel.
223 */
224 if (result && result != -EEXIST)
225 continue;
226
227 result = acpi_bind_memory_blocks(info, mem_device->device);
228 if (result) {
229 acpi_unbind_memory_blocks(info);
230 return -ENODEV;
231 }
232
233 info->enabled = 1;
234
235 /*
236 * Add num_enable even if add_memory() returns -EEXIST, so the
237 * device is bound to this driver.
238 */
239 num_enabled++;
240 }
241 if (!num_enabled) {
242 dev_err(&mem_device->device->dev, "add_memory failed\n");
243 return -EINVAL;
244 }
245 /*
246 * Sometimes the memory device will contain several memory blocks.
247 * When one memory block is hot-added to the system memory, it will
248 * be regarded as a success.
249 * Otherwise if the last memory block can't be hot-added to the system
250 * memory, it will be failure and the memory device can't be bound with
251 * driver.
252 */
253 return 0;
254}
255
256static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
257{
258 struct acpi_memory_info *info, *n;
259
260 list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
261 if (!info->enabled)
262 continue;
263
264 acpi_unbind_memory_blocks(info);
265 __remove_memory(info->start_addr, info->length);
266 list_del(&info->list);
267 kfree(info);
268 }
269}
270
271static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
272{
273 if (!mem_device)
274 return;
275
276 /* In case we succeeded adding *some* memory, unregistering fails. */
277 if (mem_device->mgid >= 0)
278 memory_group_unregister(mem_device->mgid);
279
280 acpi_memory_free_device_resources(mem_device);
281 mem_device->device->driver_data = NULL;
282 kfree(mem_device);
283}
284
285static int acpi_memory_device_add(struct acpi_device *device,
286 const struct acpi_device_id *not_used)
287{
288 struct acpi_memory_device *mem_device;
289 int result;
290
291 if (!device)
292 return -EINVAL;
293
294 mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
295 if (!mem_device)
296 return -ENOMEM;
297
298 INIT_LIST_HEAD(&mem_device->res_list);
299 mem_device->device = device;
300 mem_device->mgid = -1;
301 sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
302 sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
303 device->driver_data = mem_device;
304
305 /* Get the range from the _CRS */
306 result = acpi_memory_get_device_resources(mem_device);
307 if (result) {
308 device->driver_data = NULL;
309 kfree(mem_device);
310 return result;
311 }
312
313 result = acpi_memory_check_device(mem_device);
314 if (result) {
315 acpi_memory_device_free(mem_device);
316 return 0;
317 }
318
319 result = acpi_memory_enable_device(mem_device);
320 if (result) {
321 dev_err(&device->dev, "acpi_memory_enable_device() error\n");
322 acpi_memory_device_free(mem_device);
323 return result;
324 }
325
326 dev_dbg(&device->dev, "Memory device configured by ACPI\n");
327 return 1;
328}
329
330static void acpi_memory_device_remove(struct acpi_device *device)
331{
332 struct acpi_memory_device *mem_device;
333
334 if (!device || !acpi_driver_data(device))
335 return;
336
337 mem_device = acpi_driver_data(device);
338 acpi_memory_remove_memory(mem_device);
339 acpi_memory_device_free(mem_device);
340}
341
342static bool __initdata acpi_no_memhotplug;
343
344void __init acpi_memory_hotplug_init(void)
345{
346 if (acpi_no_memhotplug) {
347 memory_device_handler.attach = NULL;
348 acpi_scan_add_handler(&memory_device_handler);
349 return;
350 }
351 acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
352}
353
354static int __init disable_acpi_memory_hotplug(char *str)
355{
356 acpi_no_memhotplug = true;
357 return 1;
358}
359__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);
360
361#else
362
363static struct acpi_scan_handler memory_device_handler = {
364 .ids = memory_device_ids,
365};
366
367void __init acpi_memory_hotplug_init(void)
368{
369 acpi_scan_add_handler(&memory_device_handler);
370}
371
372#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */