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9aa8b50b S |
1 | /* |
2 | * Copyright (c) 2012, Microsoft Corporation. | |
3 | * | |
4 | * Author: | |
5 | * K. Y. Srinivasan <kys@microsoft.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License version 2 as published | |
9 | * by the Free Software Foundation. | |
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 | */ | |
18 | ||
19 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
20 | ||
21 | #include <linux/kernel.h> | |
ae339336 | 22 | #include <linux/jiffies.h> |
9aa8b50b S |
23 | #include <linux/mman.h> |
24 | #include <linux/delay.h> | |
25 | #include <linux/init.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/kthread.h> | |
29 | #include <linux/completion.h> | |
30 | #include <linux/memory_hotplug.h> | |
31 | #include <linux/memory.h> | |
32 | #include <linux/notifier.h> | |
9aa8b50b S |
33 | #include <linux/percpu_counter.h> |
34 | ||
35 | #include <linux/hyperv.h> | |
36 | ||
37 | /* | |
38 | * We begin with definitions supporting the Dynamic Memory protocol | |
39 | * with the host. | |
40 | * | |
41 | * Begin protocol definitions. | |
42 | */ | |
43 | ||
44 | ||
45 | ||
46 | /* | |
47 | * Protocol versions. The low word is the minor version, the high word the major | |
48 | * version. | |
49 | * | |
50 | * History: | |
51 | * Initial version 1.0 | |
52 | * Changed to 0.1 on 2009/03/25 | |
53 | * Changes to 0.2 on 2009/05/14 | |
54 | * Changes to 0.3 on 2009/12/03 | |
55 | * Changed to 1.0 on 2011/04/05 | |
56 | */ | |
57 | ||
58 | #define DYNMEM_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor))) | |
59 | #define DYNMEM_MAJOR_VERSION(Version) ((__u32)(Version) >> 16) | |
60 | #define DYNMEM_MINOR_VERSION(Version) ((__u32)(Version) & 0xff) | |
61 | ||
62 | enum { | |
63 | DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3), | |
64 | DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0), | |
65 | ||
66 | DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1, | |
67 | DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2, | |
68 | ||
69 | DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN8 | |
70 | }; | |
71 | ||
72 | ||
73 | ||
74 | /* | |
75 | * Message Types | |
76 | */ | |
77 | ||
78 | enum dm_message_type { | |
79 | /* | |
80 | * Version 0.3 | |
81 | */ | |
82 | DM_ERROR = 0, | |
83 | DM_VERSION_REQUEST = 1, | |
84 | DM_VERSION_RESPONSE = 2, | |
85 | DM_CAPABILITIES_REPORT = 3, | |
86 | DM_CAPABILITIES_RESPONSE = 4, | |
87 | DM_STATUS_REPORT = 5, | |
88 | DM_BALLOON_REQUEST = 6, | |
89 | DM_BALLOON_RESPONSE = 7, | |
90 | DM_UNBALLOON_REQUEST = 8, | |
91 | DM_UNBALLOON_RESPONSE = 9, | |
92 | DM_MEM_HOT_ADD_REQUEST = 10, | |
93 | DM_MEM_HOT_ADD_RESPONSE = 11, | |
94 | DM_VERSION_03_MAX = 11, | |
95 | /* | |
96 | * Version 1.0. | |
97 | */ | |
98 | DM_INFO_MESSAGE = 12, | |
99 | DM_VERSION_1_MAX = 12 | |
100 | }; | |
101 | ||
102 | ||
103 | /* | |
104 | * Structures defining the dynamic memory management | |
105 | * protocol. | |
106 | */ | |
107 | ||
108 | union dm_version { | |
109 | struct { | |
110 | __u16 minor_version; | |
111 | __u16 major_version; | |
112 | }; | |
113 | __u32 version; | |
114 | } __packed; | |
115 | ||
116 | ||
117 | union dm_caps { | |
118 | struct { | |
119 | __u64 balloon:1; | |
120 | __u64 hot_add:1; | |
647965a2 S |
121 | /* |
122 | * To support guests that may have alignment | |
123 | * limitations on hot-add, the guest can specify | |
124 | * its alignment requirements; a value of n | |
125 | * represents an alignment of 2^n in mega bytes. | |
126 | */ | |
127 | __u64 hot_add_alignment:4; | |
128 | __u64 reservedz:58; | |
9aa8b50b S |
129 | } cap_bits; |
130 | __u64 caps; | |
131 | } __packed; | |
132 | ||
133 | union dm_mem_page_range { | |
134 | struct { | |
135 | /* | |
136 | * The PFN number of the first page in the range. | |
137 | * 40 bits is the architectural limit of a PFN | |
138 | * number for AMD64. | |
139 | */ | |
140 | __u64 start_page:40; | |
141 | /* | |
142 | * The number of pages in the range. | |
143 | */ | |
144 | __u64 page_cnt:24; | |
145 | } finfo; | |
146 | __u64 page_range; | |
147 | } __packed; | |
148 | ||
149 | ||
150 | ||
151 | /* | |
152 | * The header for all dynamic memory messages: | |
153 | * | |
154 | * type: Type of the message. | |
155 | * size: Size of the message in bytes; including the header. | |
156 | * trans_id: The guest is responsible for manufacturing this ID. | |
157 | */ | |
158 | ||
159 | struct dm_header { | |
160 | __u16 type; | |
161 | __u16 size; | |
162 | __u32 trans_id; | |
163 | } __packed; | |
164 | ||
165 | /* | |
166 | * A generic message format for dynamic memory. | |
167 | * Specific message formats are defined later in the file. | |
168 | */ | |
169 | ||
170 | struct dm_message { | |
171 | struct dm_header hdr; | |
172 | __u8 data[]; /* enclosed message */ | |
173 | } __packed; | |
174 | ||
175 | ||
176 | /* | |
177 | * Specific message types supporting the dynamic memory protocol. | |
178 | */ | |
179 | ||
180 | /* | |
181 | * Version negotiation message. Sent from the guest to the host. | |
182 | * The guest is free to try different versions until the host | |
183 | * accepts the version. | |
184 | * | |
185 | * dm_version: The protocol version requested. | |
186 | * is_last_attempt: If TRUE, this is the last version guest will request. | |
187 | * reservedz: Reserved field, set to zero. | |
188 | */ | |
189 | ||
190 | struct dm_version_request { | |
191 | struct dm_header hdr; | |
192 | union dm_version version; | |
193 | __u32 is_last_attempt:1; | |
194 | __u32 reservedz:31; | |
195 | } __packed; | |
196 | ||
197 | /* | |
198 | * Version response message; Host to Guest and indicates | |
199 | * if the host has accepted the version sent by the guest. | |
200 | * | |
201 | * is_accepted: If TRUE, host has accepted the version and the guest | |
202 | * should proceed to the next stage of the protocol. FALSE indicates that | |
203 | * guest should re-try with a different version. | |
204 | * | |
205 | * reservedz: Reserved field, set to zero. | |
206 | */ | |
207 | ||
208 | struct dm_version_response { | |
209 | struct dm_header hdr; | |
210 | __u64 is_accepted:1; | |
211 | __u64 reservedz:63; | |
212 | } __packed; | |
213 | ||
214 | /* | |
215 | * Message reporting capabilities. This is sent from the guest to the | |
216 | * host. | |
217 | */ | |
218 | ||
219 | struct dm_capabilities { | |
220 | struct dm_header hdr; | |
221 | union dm_caps caps; | |
222 | __u64 min_page_cnt; | |
223 | __u64 max_page_number; | |
224 | } __packed; | |
225 | ||
226 | /* | |
227 | * Response to the capabilities message. This is sent from the host to the | |
228 | * guest. This message notifies if the host has accepted the guest's | |
229 | * capabilities. If the host has not accepted, the guest must shutdown | |
230 | * the service. | |
231 | * | |
232 | * is_accepted: Indicates if the host has accepted guest's capabilities. | |
233 | * reservedz: Must be 0. | |
234 | */ | |
235 | ||
236 | struct dm_capabilities_resp_msg { | |
237 | struct dm_header hdr; | |
238 | __u64 is_accepted:1; | |
239 | __u64 reservedz:63; | |
240 | } __packed; | |
241 | ||
242 | /* | |
243 | * This message is used to report memory pressure from the guest. | |
244 | * This message is not part of any transaction and there is no | |
245 | * response to this message. | |
246 | * | |
247 | * num_avail: Available memory in pages. | |
248 | * num_committed: Committed memory in pages. | |
249 | * page_file_size: The accumulated size of all page files | |
250 | * in the system in pages. | |
251 | * zero_free: The nunber of zero and free pages. | |
252 | * page_file_writes: The writes to the page file in pages. | |
253 | * io_diff: An indicator of file cache efficiency or page file activity, | |
254 | * calculated as File Cache Page Fault Count - Page Read Count. | |
255 | * This value is in pages. | |
256 | * | |
257 | * Some of these metrics are Windows specific and fortunately | |
258 | * the algorithm on the host side that computes the guest memory | |
259 | * pressure only uses num_committed value. | |
260 | */ | |
261 | ||
262 | struct dm_status { | |
263 | struct dm_header hdr; | |
264 | __u64 num_avail; | |
265 | __u64 num_committed; | |
266 | __u64 page_file_size; | |
267 | __u64 zero_free; | |
268 | __u32 page_file_writes; | |
269 | __u32 io_diff; | |
270 | } __packed; | |
271 | ||
272 | ||
273 | /* | |
274 | * Message to ask the guest to allocate memory - balloon up message. | |
275 | * This message is sent from the host to the guest. The guest may not be | |
276 | * able to allocate as much memory as requested. | |
277 | * | |
278 | * num_pages: number of pages to allocate. | |
279 | */ | |
280 | ||
281 | struct dm_balloon { | |
282 | struct dm_header hdr; | |
283 | __u32 num_pages; | |
284 | __u32 reservedz; | |
285 | } __packed; | |
286 | ||
287 | ||
288 | /* | |
289 | * Balloon response message; this message is sent from the guest | |
290 | * to the host in response to the balloon message. | |
291 | * | |
292 | * reservedz: Reserved; must be set to zero. | |
293 | * more_pages: If FALSE, this is the last message of the transaction. | |
294 | * if TRUE there will atleast one more message from the guest. | |
295 | * | |
296 | * range_count: The number of ranges in the range array. | |
297 | * | |
298 | * range_array: An array of page ranges returned to the host. | |
299 | * | |
300 | */ | |
301 | ||
302 | struct dm_balloon_response { | |
303 | struct dm_header hdr; | |
304 | __u32 reservedz; | |
305 | __u32 more_pages:1; | |
306 | __u32 range_count:31; | |
307 | union dm_mem_page_range range_array[]; | |
308 | } __packed; | |
309 | ||
310 | /* | |
311 | * Un-balloon message; this message is sent from the host | |
312 | * to the guest to give guest more memory. | |
313 | * | |
314 | * more_pages: If FALSE, this is the last message of the transaction. | |
315 | * if TRUE there will atleast one more message from the guest. | |
316 | * | |
317 | * reservedz: Reserved; must be set to zero. | |
318 | * | |
319 | * range_count: The number of ranges in the range array. | |
320 | * | |
321 | * range_array: An array of page ranges returned to the host. | |
322 | * | |
323 | */ | |
324 | ||
325 | struct dm_unballoon_request { | |
326 | struct dm_header hdr; | |
327 | __u32 more_pages:1; | |
328 | __u32 reservedz:31; | |
329 | __u32 range_count; | |
330 | union dm_mem_page_range range_array[]; | |
331 | } __packed; | |
332 | ||
333 | /* | |
334 | * Un-balloon response message; this message is sent from the guest | |
335 | * to the host in response to an unballoon request. | |
336 | * | |
337 | */ | |
338 | ||
339 | struct dm_unballoon_response { | |
340 | struct dm_header hdr; | |
341 | } __packed; | |
342 | ||
343 | ||
344 | /* | |
345 | * Hot add request message. Message sent from the host to the guest. | |
346 | * | |
347 | * mem_range: Memory range to hot add. | |
348 | * | |
349 | * On Linux we currently don't support this since we cannot hot add | |
350 | * arbitrary granularity of memory. | |
351 | */ | |
352 | ||
353 | struct dm_hot_add { | |
354 | struct dm_header hdr; | |
355 | union dm_mem_page_range range; | |
356 | } __packed; | |
357 | ||
358 | /* | |
359 | * Hot add response message. | |
360 | * This message is sent by the guest to report the status of a hot add request. | |
361 | * If page_count is less than the requested page count, then the host should | |
362 | * assume all further hot add requests will fail, since this indicates that | |
363 | * the guest has hit an upper physical memory barrier. | |
364 | * | |
365 | * Hot adds may also fail due to low resources; in this case, the guest must | |
366 | * not complete this message until the hot add can succeed, and the host must | |
367 | * not send a new hot add request until the response is sent. | |
368 | * If VSC fails to hot add memory DYNMEM_NUMBER_OF_UNSUCCESSFUL_HOTADD_ATTEMPTS | |
369 | * times it fails the request. | |
370 | * | |
371 | * | |
372 | * page_count: number of pages that were successfully hot added. | |
373 | * | |
374 | * result: result of the operation 1: success, 0: failure. | |
375 | * | |
376 | */ | |
377 | ||
378 | struct dm_hot_add_response { | |
379 | struct dm_header hdr; | |
380 | __u32 page_count; | |
381 | __u32 result; | |
382 | } __packed; | |
383 | ||
384 | /* | |
385 | * Types of information sent from host to the guest. | |
386 | */ | |
387 | ||
388 | enum dm_info_type { | |
389 | INFO_TYPE_MAX_PAGE_CNT = 0, | |
390 | MAX_INFO_TYPE | |
391 | }; | |
392 | ||
393 | ||
394 | /* | |
395 | * Header for the information message. | |
396 | */ | |
397 | ||
398 | struct dm_info_header { | |
399 | enum dm_info_type type; | |
400 | __u32 data_size; | |
401 | } __packed; | |
402 | ||
403 | /* | |
404 | * This message is sent from the host to the guest to pass | |
405 | * some relevant information (win8 addition). | |
406 | * | |
407 | * reserved: no used. | |
408 | * info_size: size of the information blob. | |
409 | * info: information blob. | |
410 | */ | |
411 | ||
412 | struct dm_info_msg { | |
6427a0d7 | 413 | struct dm_header hdr; |
9aa8b50b S |
414 | __u32 reserved; |
415 | __u32 info_size; | |
416 | __u8 info[]; | |
417 | }; | |
418 | ||
419 | /* | |
420 | * End protocol definitions. | |
421 | */ | |
422 | ||
1cac8cd4 S |
423 | /* |
424 | * State to manage hot adding memory into the guest. | |
425 | * The range start_pfn : end_pfn specifies the range | |
426 | * that the host has asked us to hot add. The range | |
427 | * start_pfn : ha_end_pfn specifies the range that we have | |
428 | * currently hot added. We hot add in multiples of 128M | |
429 | * chunks; it is possible that we may not be able to bring | |
430 | * online all the pages in the region. The range | |
5abbbb75 | 431 | * covered_end_pfn defines the pages that can |
1cac8cd4 S |
432 | * be brough online. |
433 | */ | |
434 | ||
435 | struct hv_hotadd_state { | |
436 | struct list_head list; | |
437 | unsigned long start_pfn; | |
1cac8cd4 S |
438 | unsigned long covered_end_pfn; |
439 | unsigned long ha_end_pfn; | |
440 | unsigned long end_pfn; | |
441 | }; | |
442 | ||
6571b2da S |
443 | struct balloon_state { |
444 | __u32 num_pages; | |
445 | struct work_struct wrk; | |
446 | }; | |
447 | ||
c51af826 S |
448 | struct hot_add_wrk { |
449 | union dm_mem_page_range ha_page_range; | |
1cac8cd4 | 450 | union dm_mem_page_range ha_region_range; |
c51af826 S |
451 | struct work_struct wrk; |
452 | }; | |
453 | ||
1cac8cd4 | 454 | static bool hot_add = true; |
9aa8b50b | 455 | static bool do_hot_add; |
e500d158 S |
456 | /* |
457 | * Delay reporting memory pressure by | |
458 | * the specified number of seconds. | |
459 | */ | |
1cac8cd4 | 460 | static uint pressure_report_delay = 45; |
9aa8b50b | 461 | |
ae339336 S |
462 | /* |
463 | * The last time we posted a pressure report to host. | |
464 | */ | |
465 | static unsigned long last_post_time; | |
466 | ||
9aa8b50b S |
467 | module_param(hot_add, bool, (S_IRUGO | S_IWUSR)); |
468 | MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add"); | |
469 | ||
e500d158 S |
470 | module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR)); |
471 | MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure"); | |
9aa8b50b S |
472 | static atomic_t trans_id = ATOMIC_INIT(0); |
473 | ||
474 | static int dm_ring_size = (5 * PAGE_SIZE); | |
475 | ||
476 | /* | |
477 | * Driver specific state. | |
478 | */ | |
479 | ||
480 | enum hv_dm_state { | |
481 | DM_INITIALIZING = 0, | |
482 | DM_INITIALIZED, | |
483 | DM_BALLOON_UP, | |
484 | DM_BALLOON_DOWN, | |
485 | DM_HOT_ADD, | |
486 | DM_INIT_ERROR | |
487 | }; | |
488 | ||
489 | ||
490 | static __u8 recv_buffer[PAGE_SIZE]; | |
491 | static __u8 *send_buffer; | |
492 | #define PAGES_IN_2M 512 | |
1cac8cd4 | 493 | #define HA_CHUNK (32 * 1024) |
9aa8b50b S |
494 | |
495 | struct hv_dynmem_device { | |
496 | struct hv_device *dev; | |
497 | enum hv_dm_state state; | |
498 | struct completion host_event; | |
499 | struct completion config_event; | |
500 | ||
501 | /* | |
502 | * Number of pages we have currently ballooned out. | |
503 | */ | |
504 | unsigned int num_pages_ballooned; | |
549fd280 VK |
505 | unsigned int num_pages_onlined; |
506 | unsigned int num_pages_added; | |
9aa8b50b S |
507 | |
508 | /* | |
6571b2da S |
509 | * State to manage the ballooning (up) operation. |
510 | */ | |
511 | struct balloon_state balloon_wrk; | |
512 | ||
c51af826 S |
513 | /* |
514 | * State to execute the "hot-add" operation. | |
515 | */ | |
516 | struct hot_add_wrk ha_wrk; | |
517 | ||
1cac8cd4 S |
518 | /* |
519 | * This state tracks if the host has specified a hot-add | |
520 | * region. | |
521 | */ | |
522 | bool host_specified_ha_region; | |
523 | ||
524 | /* | |
525 | * State to synchronize hot-add. | |
526 | */ | |
527 | struct completion ol_waitevent; | |
528 | bool ha_waiting; | |
6571b2da S |
529 | /* |
530 | * This thread handles hot-add | |
9aa8b50b S |
531 | * requests from the host as well as notifying |
532 | * the host with regards to memory pressure in | |
533 | * the guest. | |
534 | */ | |
535 | struct task_struct *thread; | |
536 | ||
22f88475 | 537 | struct mutex ha_region_mutex; |
22f88475 | 538 | |
1cac8cd4 S |
539 | /* |
540 | * A list of hot-add regions. | |
541 | */ | |
542 | struct list_head ha_region_list; | |
543 | ||
9aa8b50b S |
544 | /* |
545 | * We start with the highest version we can support | |
546 | * and downgrade based on the host; we save here the | |
547 | * next version to try. | |
548 | */ | |
549 | __u32 next_version; | |
550 | }; | |
551 | ||
552 | static struct hv_dynmem_device dm_device; | |
553 | ||
ae339336 | 554 | static void post_status(struct hv_dynmem_device *dm); |
22f88475 | 555 | |
1cac8cd4 | 556 | #ifdef CONFIG_MEMORY_HOTPLUG |
22f88475 S |
557 | static int hv_memory_notifier(struct notifier_block *nb, unsigned long val, |
558 | void *v) | |
559 | { | |
549fd280 VK |
560 | struct memory_notify *mem = (struct memory_notify *)v; |
561 | ||
22f88475 S |
562 | switch (val) { |
563 | case MEM_GOING_ONLINE: | |
b05d8d9e | 564 | mutex_lock(&dm_device.ha_region_mutex); |
22f88475 S |
565 | break; |
566 | ||
567 | case MEM_ONLINE: | |
549fd280 | 568 | dm_device.num_pages_onlined += mem->nr_pages; |
22f88475 | 569 | case MEM_CANCEL_ONLINE: |
4e4bd36f VK |
570 | if (val == MEM_ONLINE || |
571 | mutex_is_locked(&dm_device.ha_region_mutex)) | |
572 | mutex_unlock(&dm_device.ha_region_mutex); | |
22f88475 S |
573 | if (dm_device.ha_waiting) { |
574 | dm_device.ha_waiting = false; | |
575 | complete(&dm_device.ol_waitevent); | |
576 | } | |
577 | break; | |
578 | ||
22f88475 | 579 | case MEM_OFFLINE: |
549fd280 VK |
580 | mutex_lock(&dm_device.ha_region_mutex); |
581 | dm_device.num_pages_onlined -= mem->nr_pages; | |
582 | mutex_unlock(&dm_device.ha_region_mutex); | |
583 | break; | |
584 | case MEM_GOING_OFFLINE: | |
22f88475 S |
585 | case MEM_CANCEL_OFFLINE: |
586 | break; | |
587 | } | |
588 | return NOTIFY_OK; | |
589 | } | |
590 | ||
591 | static struct notifier_block hv_memory_nb = { | |
592 | .notifier_call = hv_memory_notifier, | |
593 | .priority = 0 | |
594 | }; | |
595 | ||
1cac8cd4 | 596 | |
a6025a2a | 597 | static void hv_bring_pgs_online(unsigned long start_pfn, unsigned long size) |
9aa8b50b | 598 | { |
1cac8cd4 | 599 | int i; |
9aa8b50b | 600 | |
1cac8cd4 S |
601 | for (i = 0; i < size; i++) { |
602 | struct page *pg; | |
603 | pg = pfn_to_page(start_pfn + i); | |
604 | __online_page_set_limits(pg); | |
605 | __online_page_increment_counters(pg); | |
606 | __online_page_free(pg); | |
607 | } | |
608 | } | |
609 | ||
610 | static void hv_mem_hot_add(unsigned long start, unsigned long size, | |
611 | unsigned long pfn_count, | |
612 | struct hv_hotadd_state *has) | |
613 | { | |
614 | int ret = 0; | |
ed07ec93 | 615 | int i, nid; |
1cac8cd4 S |
616 | unsigned long start_pfn; |
617 | unsigned long processed_pfn; | |
618 | unsigned long total_pfn = pfn_count; | |
619 | ||
620 | for (i = 0; i < (size/HA_CHUNK); i++) { | |
621 | start_pfn = start + (i * HA_CHUNK); | |
622 | has->ha_end_pfn += HA_CHUNK; | |
623 | ||
624 | if (total_pfn > HA_CHUNK) { | |
625 | processed_pfn = HA_CHUNK; | |
626 | total_pfn -= HA_CHUNK; | |
627 | } else { | |
628 | processed_pfn = total_pfn; | |
629 | total_pfn = 0; | |
630 | } | |
631 | ||
632 | has->covered_end_pfn += processed_pfn; | |
9aa8b50b | 633 | |
1cac8cd4 S |
634 | init_completion(&dm_device.ol_waitevent); |
635 | dm_device.ha_waiting = true; | |
9aa8b50b | 636 | |
b05d8d9e | 637 | mutex_unlock(&dm_device.ha_region_mutex); |
1cac8cd4 S |
638 | nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn)); |
639 | ret = add_memory(nid, PFN_PHYS((start_pfn)), | |
640 | (HA_CHUNK << PAGE_SHIFT)); | |
641 | ||
642 | if (ret) { | |
643 | pr_info("hot_add memory failed error is %d\n", ret); | |
7f4f2302 S |
644 | if (ret == -EEXIST) { |
645 | /* | |
646 | * This error indicates that the error | |
647 | * is not a transient failure. This is the | |
648 | * case where the guest's physical address map | |
649 | * precludes hot adding memory. Stop all further | |
650 | * memory hot-add. | |
651 | */ | |
652 | do_hot_add = false; | |
653 | } | |
1cac8cd4 S |
654 | has->ha_end_pfn -= HA_CHUNK; |
655 | has->covered_end_pfn -= processed_pfn; | |
f3f6eb80 | 656 | mutex_lock(&dm_device.ha_region_mutex); |
1cac8cd4 S |
657 | break; |
658 | } | |
9aa8b50b S |
659 | |
660 | /* | |
1cac8cd4 | 661 | * Wait for the memory block to be onlined. |
ed07ec93 S |
662 | * Since the hot add has succeeded, it is ok to |
663 | * proceed even if the pages in the hot added region | |
664 | * have not been "onlined" within the allowed time. | |
9aa8b50b | 665 | */ |
ed07ec93 | 666 | wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ); |
b05d8d9e | 667 | mutex_lock(&dm_device.ha_region_mutex); |
ae339336 | 668 | post_status(&dm_device); |
9aa8b50b S |
669 | } |
670 | ||
1cac8cd4 S |
671 | return; |
672 | } | |
673 | ||
674 | static void hv_online_page(struct page *pg) | |
675 | { | |
676 | struct list_head *cur; | |
677 | struct hv_hotadd_state *has; | |
678 | unsigned long cur_start_pgp; | |
679 | unsigned long cur_end_pgp; | |
680 | ||
1cac8cd4 S |
681 | list_for_each(cur, &dm_device.ha_region_list) { |
682 | has = list_entry(cur, struct hv_hotadd_state, list); | |
5abbbb75 | 683 | cur_start_pgp = (unsigned long)pfn_to_page(has->start_pfn); |
1cac8cd4 S |
684 | cur_end_pgp = (unsigned long)pfn_to_page(has->covered_end_pfn); |
685 | ||
686 | if (((unsigned long)pg >= cur_start_pgp) && | |
687 | ((unsigned long)pg < cur_end_pgp)) { | |
688 | /* | |
689 | * This frame is currently backed; online the | |
690 | * page. | |
691 | */ | |
692 | __online_page_set_limits(pg); | |
693 | __online_page_increment_counters(pg); | |
694 | __online_page_free(pg); | |
1cac8cd4 S |
695 | } |
696 | } | |
697 | } | |
698 | ||
699 | static bool pfn_covered(unsigned long start_pfn, unsigned long pfn_cnt) | |
700 | { | |
701 | struct list_head *cur; | |
702 | struct hv_hotadd_state *has; | |
703 | unsigned long residual, new_inc; | |
704 | ||
705 | if (list_empty(&dm_device.ha_region_list)) | |
706 | return false; | |
707 | ||
708 | list_for_each(cur, &dm_device.ha_region_list) { | |
709 | has = list_entry(cur, struct hv_hotadd_state, list); | |
710 | ||
711 | /* | |
712 | * If the pfn range we are dealing with is not in the current | |
713 | * "hot add block", move on. | |
714 | */ | |
715 | if ((start_pfn >= has->end_pfn)) | |
716 | continue; | |
717 | /* | |
718 | * If the current hot add-request extends beyond | |
719 | * our current limit; extend it. | |
720 | */ | |
721 | if ((start_pfn + pfn_cnt) > has->end_pfn) { | |
722 | residual = (start_pfn + pfn_cnt - has->end_pfn); | |
723 | /* | |
724 | * Extend the region by multiples of HA_CHUNK. | |
725 | */ | |
726 | new_inc = (residual / HA_CHUNK) * HA_CHUNK; | |
727 | if (residual % HA_CHUNK) | |
728 | new_inc += HA_CHUNK; | |
729 | ||
730 | has->end_pfn += new_inc; | |
731 | } | |
732 | ||
733 | /* | |
734 | * If the current start pfn is not where the covered_end | |
735 | * is, update it. | |
736 | */ | |
737 | ||
5abbbb75 | 738 | if (has->covered_end_pfn != start_pfn) |
1cac8cd4 | 739 | has->covered_end_pfn = start_pfn; |
5abbbb75 | 740 | |
1cac8cd4 S |
741 | return true; |
742 | ||
743 | } | |
744 | ||
745 | return false; | |
746 | } | |
747 | ||
748 | static unsigned long handle_pg_range(unsigned long pg_start, | |
749 | unsigned long pg_count) | |
750 | { | |
751 | unsigned long start_pfn = pg_start; | |
752 | unsigned long pfn_cnt = pg_count; | |
753 | unsigned long size; | |
754 | struct list_head *cur; | |
755 | struct hv_hotadd_state *has; | |
756 | unsigned long pgs_ol = 0; | |
757 | unsigned long old_covered_state; | |
758 | ||
759 | if (list_empty(&dm_device.ha_region_list)) | |
760 | return 0; | |
761 | ||
762 | list_for_each(cur, &dm_device.ha_region_list) { | |
763 | has = list_entry(cur, struct hv_hotadd_state, list); | |
764 | ||
765 | /* | |
766 | * If the pfn range we are dealing with is not in the current | |
767 | * "hot add block", move on. | |
768 | */ | |
769 | if ((start_pfn >= has->end_pfn)) | |
770 | continue; | |
771 | ||
772 | old_covered_state = has->covered_end_pfn; | |
773 | ||
774 | if (start_pfn < has->ha_end_pfn) { | |
775 | /* | |
776 | * This is the case where we are backing pages | |
777 | * in an already hot added region. Bring | |
778 | * these pages online first. | |
779 | */ | |
780 | pgs_ol = has->ha_end_pfn - start_pfn; | |
781 | if (pgs_ol > pfn_cnt) | |
782 | pgs_ol = pfn_cnt; | |
d6cbd2c3 VK |
783 | |
784 | /* | |
785 | * Check if the corresponding memory block is already | |
786 | * online by checking its last previously backed page. | |
787 | * In case it is we need to bring rest (which was not | |
788 | * backed previously) online too. | |
789 | */ | |
790 | if (start_pfn > has->start_pfn && | |
791 | !PageReserved(pfn_to_page(start_pfn - 1))) | |
792 | hv_bring_pgs_online(start_pfn, pgs_ol); | |
793 | ||
1cac8cd4 | 794 | has->covered_end_pfn += pgs_ol; |
1cac8cd4 S |
795 | pfn_cnt -= pgs_ol; |
796 | } | |
797 | ||
798 | if ((has->ha_end_pfn < has->end_pfn) && (pfn_cnt > 0)) { | |
799 | /* | |
800 | * We have some residual hot add range | |
801 | * that needs to be hot added; hot add | |
802 | * it now. Hot add a multiple of | |
803 | * of HA_CHUNK that fully covers the pages | |
804 | * we have. | |
805 | */ | |
806 | size = (has->end_pfn - has->ha_end_pfn); | |
807 | if (pfn_cnt <= size) { | |
808 | size = ((pfn_cnt / HA_CHUNK) * HA_CHUNK); | |
809 | if (pfn_cnt % HA_CHUNK) | |
810 | size += HA_CHUNK; | |
811 | } else { | |
812 | pfn_cnt = size; | |
813 | } | |
814 | hv_mem_hot_add(has->ha_end_pfn, size, pfn_cnt, has); | |
815 | } | |
816 | /* | |
817 | * If we managed to online any pages that were given to us, | |
818 | * we declare success. | |
819 | */ | |
820 | return has->covered_end_pfn - old_covered_state; | |
821 | ||
822 | } | |
823 | ||
824 | return 0; | |
825 | } | |
826 | ||
827 | static unsigned long process_hot_add(unsigned long pg_start, | |
828 | unsigned long pfn_cnt, | |
829 | unsigned long rg_start, | |
830 | unsigned long rg_size) | |
831 | { | |
832 | struct hv_hotadd_state *ha_region = NULL; | |
833 | ||
834 | if (pfn_cnt == 0) | |
835 | return 0; | |
836 | ||
837 | if (!dm_device.host_specified_ha_region) | |
838 | if (pfn_covered(pg_start, pfn_cnt)) | |
839 | goto do_pg_range; | |
840 | ||
841 | /* | |
842 | * If the host has specified a hot-add range; deal with it first. | |
843 | */ | |
844 | ||
647965a2 | 845 | if (rg_size != 0) { |
1cac8cd4 S |
846 | ha_region = kzalloc(sizeof(struct hv_hotadd_state), GFP_KERNEL); |
847 | if (!ha_region) | |
848 | return 0; | |
849 | ||
850 | INIT_LIST_HEAD(&ha_region->list); | |
851 | ||
852 | list_add_tail(&ha_region->list, &dm_device.ha_region_list); | |
853 | ha_region->start_pfn = rg_start; | |
854 | ha_region->ha_end_pfn = rg_start; | |
1cac8cd4 S |
855 | ha_region->covered_end_pfn = pg_start; |
856 | ha_region->end_pfn = rg_start + rg_size; | |
857 | } | |
858 | ||
859 | do_pg_range: | |
860 | /* | |
861 | * Process the page range specified; bringing them | |
862 | * online if possible. | |
863 | */ | |
864 | return handle_pg_range(pg_start, pfn_cnt); | |
865 | } | |
866 | ||
867 | #endif | |
868 | ||
869 | static void hot_add_req(struct work_struct *dummy) | |
870 | { | |
871 | struct dm_hot_add_response resp; | |
872 | #ifdef CONFIG_MEMORY_HOTPLUG | |
873 | unsigned long pg_start, pfn_cnt; | |
874 | unsigned long rg_start, rg_sz; | |
875 | #endif | |
876 | struct hv_dynmem_device *dm = &dm_device; | |
877 | ||
9aa8b50b S |
878 | memset(&resp, 0, sizeof(struct dm_hot_add_response)); |
879 | resp.hdr.type = DM_MEM_HOT_ADD_RESPONSE; | |
880 | resp.hdr.size = sizeof(struct dm_hot_add_response); | |
9aa8b50b | 881 | |
1cac8cd4 | 882 | #ifdef CONFIG_MEMORY_HOTPLUG |
b05d8d9e | 883 | mutex_lock(&dm_device.ha_region_mutex); |
1cac8cd4 S |
884 | pg_start = dm->ha_wrk.ha_page_range.finfo.start_page; |
885 | pfn_cnt = dm->ha_wrk.ha_page_range.finfo.page_cnt; | |
9aa8b50b | 886 | |
1cac8cd4 S |
887 | rg_start = dm->ha_wrk.ha_region_range.finfo.start_page; |
888 | rg_sz = dm->ha_wrk.ha_region_range.finfo.page_cnt; | |
889 | ||
890 | if ((rg_start == 0) && (!dm->host_specified_ha_region)) { | |
891 | unsigned long region_size; | |
892 | unsigned long region_start; | |
893 | ||
894 | /* | |
895 | * The host has not specified the hot-add region. | |
896 | * Based on the hot-add page range being specified, | |
897 | * compute a hot-add region that can cover the pages | |
898 | * that need to be hot-added while ensuring the alignment | |
899 | * and size requirements of Linux as it relates to hot-add. | |
900 | */ | |
901 | region_start = pg_start; | |
902 | region_size = (pfn_cnt / HA_CHUNK) * HA_CHUNK; | |
903 | if (pfn_cnt % HA_CHUNK) | |
904 | region_size += HA_CHUNK; | |
905 | ||
906 | region_start = (pg_start / HA_CHUNK) * HA_CHUNK; | |
907 | ||
908 | rg_start = region_start; | |
909 | rg_sz = region_size; | |
910 | } | |
911 | ||
7f4f2302 S |
912 | if (do_hot_add) |
913 | resp.page_count = process_hot_add(pg_start, pfn_cnt, | |
914 | rg_start, rg_sz); | |
549fd280 VK |
915 | |
916 | dm->num_pages_added += resp.page_count; | |
b05d8d9e | 917 | mutex_unlock(&dm_device.ha_region_mutex); |
1cac8cd4 | 918 | #endif |
7f4f2302 S |
919 | /* |
920 | * The result field of the response structure has the | |
921 | * following semantics: | |
922 | * | |
923 | * 1. If all or some pages hot-added: Guest should return success. | |
924 | * | |
925 | * 2. If no pages could be hot-added: | |
926 | * | |
927 | * If the guest returns success, then the host | |
928 | * will not attempt any further hot-add operations. This | |
929 | * signifies a permanent failure. | |
930 | * | |
931 | * If the guest returns failure, then this failure will be | |
932 | * treated as a transient failure and the host may retry the | |
933 | * hot-add operation after some delay. | |
934 | */ | |
1cac8cd4 S |
935 | if (resp.page_count > 0) |
936 | resp.result = 1; | |
7f4f2302 S |
937 | else if (!do_hot_add) |
938 | resp.result = 1; | |
1cac8cd4 S |
939 | else |
940 | resp.result = 0; | |
941 | ||
942 | if (!do_hot_add || (resp.page_count == 0)) | |
943 | pr_info("Memory hot add failed\n"); | |
944 | ||
945 | dm->state = DM_INITIALIZED; | |
20138d6c | 946 | resp.hdr.trans_id = atomic_inc_return(&trans_id); |
1cac8cd4 | 947 | vmbus_sendpacket(dm->dev->channel, &resp, |
9aa8b50b S |
948 | sizeof(struct dm_hot_add_response), |
949 | (unsigned long)NULL, | |
950 | VM_PKT_DATA_INBAND, 0); | |
9aa8b50b S |
951 | } |
952 | ||
953 | static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg) | |
954 | { | |
6427a0d7 S |
955 | struct dm_info_header *info_hdr; |
956 | ||
957 | info_hdr = (struct dm_info_header *)msg->info; | |
958 | ||
959 | switch (info_hdr->type) { | |
9aa8b50b S |
960 | case INFO_TYPE_MAX_PAGE_CNT: |
961 | pr_info("Received INFO_TYPE_MAX_PAGE_CNT\n"); | |
6427a0d7 | 962 | pr_info("Data Size is %d\n", info_hdr->data_size); |
9aa8b50b S |
963 | break; |
964 | default: | |
6427a0d7 | 965 | pr_info("Received Unknown type: %d\n", info_hdr->type); |
9aa8b50b S |
966 | } |
967 | } | |
968 | ||
a6025a2a | 969 | static unsigned long compute_balloon_floor(void) |
1c7db96f S |
970 | { |
971 | unsigned long min_pages; | |
972 | #define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT)) | |
973 | /* Simple continuous piecewiese linear function: | |
974 | * max MiB -> min MiB gradient | |
975 | * 0 0 | |
976 | * 16 16 | |
977 | * 32 24 | |
978 | * 128 72 (1/2) | |
979 | * 512 168 (1/4) | |
980 | * 2048 360 (1/8) | |
7fb0e1a6 VK |
981 | * 8192 744 (1/16) |
982 | * 32768 1512 (1/32) | |
1c7db96f S |
983 | */ |
984 | if (totalram_pages < MB2PAGES(128)) | |
985 | min_pages = MB2PAGES(8) + (totalram_pages >> 1); | |
986 | else if (totalram_pages < MB2PAGES(512)) | |
987 | min_pages = MB2PAGES(40) + (totalram_pages >> 2); | |
988 | else if (totalram_pages < MB2PAGES(2048)) | |
989 | min_pages = MB2PAGES(104) + (totalram_pages >> 3); | |
79208c57 | 990 | else if (totalram_pages < MB2PAGES(8192)) |
7fb0e1a6 | 991 | min_pages = MB2PAGES(232) + (totalram_pages >> 4); |
1c7db96f | 992 | else |
7fb0e1a6 | 993 | min_pages = MB2PAGES(488) + (totalram_pages >> 5); |
1c7db96f S |
994 | #undef MB2PAGES |
995 | return min_pages; | |
996 | } | |
997 | ||
9aa8b50b S |
998 | /* |
999 | * Post our status as it relates memory pressure to the | |
1000 | * host. Host expects the guests to post this status | |
1001 | * periodically at 1 second intervals. | |
1002 | * | |
1003 | * The metrics specified in this protocol are very Windows | |
1004 | * specific and so we cook up numbers here to convey our memory | |
1005 | * pressure. | |
1006 | */ | |
1007 | ||
1008 | static void post_status(struct hv_dynmem_device *dm) | |
1009 | { | |
1010 | struct dm_status status; | |
0731572b | 1011 | struct sysinfo val; |
ae339336 S |
1012 | unsigned long now = jiffies; |
1013 | unsigned long last_post = last_post_time; | |
9aa8b50b | 1014 | |
e500d158 S |
1015 | if (pressure_report_delay > 0) { |
1016 | --pressure_report_delay; | |
1017 | return; | |
1018 | } | |
ae339336 S |
1019 | |
1020 | if (!time_after(now, (last_post_time + HZ))) | |
1021 | return; | |
1022 | ||
0731572b | 1023 | si_meminfo(&val); |
9aa8b50b S |
1024 | memset(&status, 0, sizeof(struct dm_status)); |
1025 | status.hdr.type = DM_STATUS_REPORT; | |
1026 | status.hdr.size = sizeof(struct dm_status); | |
1027 | status.hdr.trans_id = atomic_inc_return(&trans_id); | |
1028 | ||
0731572b | 1029 | /* |
549fd280 VK |
1030 | * The host expects the guest to report free and committed memory. |
1031 | * Furthermore, the host expects the pressure information to include | |
1032 | * the ballooned out pages. For a given amount of memory that we are | |
1033 | * managing we need to compute a floor below which we should not | |
1034 | * balloon. Compute this and add it to the pressure report. | |
1035 | * We also need to report all offline pages (num_pages_added - | |
1036 | * num_pages_onlined) as committed to the host, otherwise it can try | |
1037 | * asking us to balloon them out. | |
0731572b S |
1038 | */ |
1039 | status.num_avail = val.freeram; | |
1c7db96f | 1040 | status.num_committed = vm_memory_committed() + |
549fd280 VK |
1041 | dm->num_pages_ballooned + |
1042 | (dm->num_pages_added > dm->num_pages_onlined ? | |
1043 | dm->num_pages_added - dm->num_pages_onlined : 0) + | |
1044 | compute_balloon_floor(); | |
9aa8b50b | 1045 | |
c5e2254f S |
1046 | /* |
1047 | * If our transaction ID is no longer current, just don't | |
1048 | * send the status. This can happen if we were interrupted | |
1049 | * after we picked our transaction ID. | |
1050 | */ | |
1051 | if (status.hdr.trans_id != atomic_read(&trans_id)) | |
1052 | return; | |
1053 | ||
ae339336 S |
1054 | /* |
1055 | * If the last post time that we sampled has changed, | |
1056 | * we have raced, don't post the status. | |
1057 | */ | |
1058 | if (last_post != last_post_time) | |
1059 | return; | |
1060 | ||
1061 | last_post_time = jiffies; | |
9aa8b50b S |
1062 | vmbus_sendpacket(dm->dev->channel, &status, |
1063 | sizeof(struct dm_status), | |
1064 | (unsigned long)NULL, | |
1065 | VM_PKT_DATA_INBAND, 0); | |
1066 | ||
1067 | } | |
1068 | ||
989623c7 | 1069 | static void free_balloon_pages(struct hv_dynmem_device *dm, |
9aa8b50b S |
1070 | union dm_mem_page_range *range_array) |
1071 | { | |
1072 | int num_pages = range_array->finfo.page_cnt; | |
1073 | __u64 start_frame = range_array->finfo.start_page; | |
1074 | struct page *pg; | |
1075 | int i; | |
1076 | ||
1077 | for (i = 0; i < num_pages; i++) { | |
1078 | pg = pfn_to_page(i + start_frame); | |
1079 | __free_page(pg); | |
1080 | dm->num_pages_ballooned--; | |
1081 | } | |
1082 | } | |
1083 | ||
1084 | ||
1085 | ||
797f88c9 VK |
1086 | static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm, |
1087 | unsigned int num_pages, | |
1088 | struct dm_balloon_response *bl_resp, | |
1089 | int alloc_unit) | |
9aa8b50b | 1090 | { |
797f88c9 | 1091 | unsigned int i = 0; |
9aa8b50b S |
1092 | struct page *pg; |
1093 | ||
1094 | if (num_pages < alloc_unit) | |
1095 | return 0; | |
1096 | ||
1097 | for (i = 0; (i * alloc_unit) < num_pages; i++) { | |
1098 | if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) > | |
1099 | PAGE_SIZE) | |
1100 | return i * alloc_unit; | |
1101 | ||
1102 | /* | |
1103 | * We execute this code in a thread context. Furthermore, | |
1104 | * we don't want the kernel to try too hard. | |
1105 | */ | |
1106 | pg = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY | | |
1107 | __GFP_NOMEMALLOC | __GFP_NOWARN, | |
1108 | get_order(alloc_unit << PAGE_SHIFT)); | |
1109 | ||
0a1a86ac | 1110 | if (!pg) |
9aa8b50b | 1111 | return i * alloc_unit; |
9aa8b50b S |
1112 | |
1113 | dm->num_pages_ballooned += alloc_unit; | |
1114 | ||
f766dc1e S |
1115 | /* |
1116 | * If we allocatted 2M pages; split them so we | |
1117 | * can free them in any order we get. | |
1118 | */ | |
1119 | ||
1120 | if (alloc_unit != 1) | |
1121 | split_page(pg, get_order(alloc_unit << PAGE_SHIFT)); | |
1122 | ||
9aa8b50b S |
1123 | bl_resp->range_count++; |
1124 | bl_resp->range_array[i].finfo.start_page = | |
1125 | page_to_pfn(pg); | |
1126 | bl_resp->range_array[i].finfo.page_cnt = alloc_unit; | |
1127 | bl_resp->hdr.size += sizeof(union dm_mem_page_range); | |
1128 | ||
1129 | } | |
1130 | ||
1131 | return num_pages; | |
1132 | } | |
1133 | ||
1134 | ||
1135 | ||
6571b2da | 1136 | static void balloon_up(struct work_struct *dummy) |
9aa8b50b | 1137 | { |
797f88c9 VK |
1138 | unsigned int num_pages = dm_device.balloon_wrk.num_pages; |
1139 | unsigned int num_ballooned = 0; | |
9aa8b50b S |
1140 | struct dm_balloon_response *bl_resp; |
1141 | int alloc_unit; | |
1142 | int ret; | |
9aa8b50b S |
1143 | bool done = false; |
1144 | int i; | |
530d15b9 VK |
1145 | struct sysinfo val; |
1146 | unsigned long floor; | |
9aa8b50b | 1147 | |
f6712238 DC |
1148 | /* The host balloons pages in 2M granularity. */ |
1149 | WARN_ON_ONCE(num_pages % PAGES_IN_2M != 0); | |
9aa8b50b S |
1150 | |
1151 | /* | |
f766dc1e S |
1152 | * We will attempt 2M allocations. However, if we fail to |
1153 | * allocate 2M chunks, we will go back to 4k allocations. | |
9aa8b50b | 1154 | */ |
f766dc1e | 1155 | alloc_unit = 512; |
9aa8b50b | 1156 | |
530d15b9 VK |
1157 | si_meminfo(&val); |
1158 | floor = compute_balloon_floor(); | |
1159 | ||
1160 | /* Refuse to balloon below the floor, keep the 2M granularity. */ | |
ba0c4441 | 1161 | if (val.freeram < num_pages || val.freeram - num_pages < floor) { |
530d15b9 VK |
1162 | num_pages = val.freeram > floor ? (val.freeram - floor) : 0; |
1163 | num_pages -= num_pages % PAGES_IN_2M; | |
1164 | } | |
1165 | ||
9aa8b50b S |
1166 | while (!done) { |
1167 | bl_resp = (struct dm_balloon_response *)send_buffer; | |
1168 | memset(send_buffer, 0, PAGE_SIZE); | |
1169 | bl_resp->hdr.type = DM_BALLOON_RESPONSE; | |
9aa8b50b S |
1170 | bl_resp->hdr.size = sizeof(struct dm_balloon_response); |
1171 | bl_resp->more_pages = 1; | |
1172 | ||
1173 | ||
1174 | num_pages -= num_ballooned; | |
6571b2da | 1175 | num_ballooned = alloc_balloon_pages(&dm_device, num_pages, |
0a1a86ac | 1176 | bl_resp, alloc_unit); |
9aa8b50b | 1177 | |
f6712238 | 1178 | if (alloc_unit != 1 && num_ballooned == 0) { |
f766dc1e S |
1179 | alloc_unit = 1; |
1180 | continue; | |
1181 | } | |
1182 | ||
0a1a86ac | 1183 | if (num_ballooned == 0 || num_ballooned == num_pages) { |
9aa8b50b S |
1184 | bl_resp->more_pages = 0; |
1185 | done = true; | |
6571b2da | 1186 | dm_device.state = DM_INITIALIZED; |
9aa8b50b S |
1187 | } |
1188 | ||
1189 | /* | |
1190 | * We are pushing a lot of data through the channel; | |
1191 | * deal with transient failures caused because of the | |
1192 | * lack of space in the ring buffer. | |
1193 | */ | |
1194 | ||
1195 | do { | |
20138d6c | 1196 | bl_resp->hdr.trans_id = atomic_inc_return(&trans_id); |
9aa8b50b S |
1197 | ret = vmbus_sendpacket(dm_device.dev->channel, |
1198 | bl_resp, | |
1199 | bl_resp->hdr.size, | |
1200 | (unsigned long)NULL, | |
1201 | VM_PKT_DATA_INBAND, 0); | |
1202 | ||
1203 | if (ret == -EAGAIN) | |
1204 | msleep(20); | |
ae339336 | 1205 | post_status(&dm_device); |
9aa8b50b S |
1206 | } while (ret == -EAGAIN); |
1207 | ||
1208 | if (ret) { | |
1209 | /* | |
1210 | * Free up the memory we allocatted. | |
1211 | */ | |
1212 | pr_info("Balloon response failed\n"); | |
1213 | ||
1214 | for (i = 0; i < bl_resp->range_count; i++) | |
6571b2da | 1215 | free_balloon_pages(&dm_device, |
9aa8b50b S |
1216 | &bl_resp->range_array[i]); |
1217 | ||
1218 | done = true; | |
1219 | } | |
1220 | } | |
1221 | ||
1222 | } | |
1223 | ||
1224 | static void balloon_down(struct hv_dynmem_device *dm, | |
1225 | struct dm_unballoon_request *req) | |
1226 | { | |
1227 | union dm_mem_page_range *range_array = req->range_array; | |
1228 | int range_count = req->range_count; | |
1229 | struct dm_unballoon_response resp; | |
1230 | int i; | |
1231 | ||
ae339336 | 1232 | for (i = 0; i < range_count; i++) { |
9aa8b50b | 1233 | free_balloon_pages(dm, &range_array[i]); |
ab3de22b | 1234 | complete(&dm_device.config_event); |
ae339336 | 1235 | } |
9aa8b50b S |
1236 | |
1237 | if (req->more_pages == 1) | |
1238 | return; | |
1239 | ||
1240 | memset(&resp, 0, sizeof(struct dm_unballoon_response)); | |
1241 | resp.hdr.type = DM_UNBALLOON_RESPONSE; | |
1242 | resp.hdr.trans_id = atomic_inc_return(&trans_id); | |
1243 | resp.hdr.size = sizeof(struct dm_unballoon_response); | |
1244 | ||
1245 | vmbus_sendpacket(dm_device.dev->channel, &resp, | |
1246 | sizeof(struct dm_unballoon_response), | |
1247 | (unsigned long)NULL, | |
1248 | VM_PKT_DATA_INBAND, 0); | |
1249 | ||
1250 | dm->state = DM_INITIALIZED; | |
1251 | } | |
1252 | ||
1253 | static void balloon_onchannelcallback(void *context); | |
1254 | ||
1255 | static int dm_thread_func(void *dm_dev) | |
1256 | { | |
1257 | struct hv_dynmem_device *dm = dm_dev; | |
9aa8b50b S |
1258 | |
1259 | while (!kthread_should_stop()) { | |
ab3de22b | 1260 | wait_for_completion_interruptible_timeout( |
5dba4c56 | 1261 | &dm_device.config_event, 1*HZ); |
9aa8b50b S |
1262 | /* |
1263 | * The host expects us to post information on the memory | |
1264 | * pressure every second. | |
1265 | */ | |
ab3de22b S |
1266 | reinit_completion(&dm_device.config_event); |
1267 | post_status(dm); | |
9aa8b50b S |
1268 | } |
1269 | ||
1270 | return 0; | |
1271 | } | |
1272 | ||
1273 | ||
1274 | static void version_resp(struct hv_dynmem_device *dm, | |
1275 | struct dm_version_response *vresp) | |
1276 | { | |
1277 | struct dm_version_request version_req; | |
1278 | int ret; | |
1279 | ||
1280 | if (vresp->is_accepted) { | |
1281 | /* | |
1282 | * We are done; wakeup the | |
1283 | * context waiting for version | |
1284 | * negotiation. | |
1285 | */ | |
1286 | complete(&dm->host_event); | |
1287 | return; | |
1288 | } | |
1289 | /* | |
1290 | * If there are more versions to try, continue | |
1291 | * with negotiations; if not | |
1292 | * shutdown the service since we are not able | |
1293 | * to negotiate a suitable version number | |
1294 | * with the host. | |
1295 | */ | |
1296 | if (dm->next_version == 0) | |
1297 | goto version_error; | |
1298 | ||
1299 | dm->next_version = 0; | |
1300 | memset(&version_req, 0, sizeof(struct dm_version_request)); | |
1301 | version_req.hdr.type = DM_VERSION_REQUEST; | |
1302 | version_req.hdr.size = sizeof(struct dm_version_request); | |
1303 | version_req.hdr.trans_id = atomic_inc_return(&trans_id); | |
1304 | version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN7; | |
1305 | version_req.is_last_attempt = 1; | |
1306 | ||
1307 | ret = vmbus_sendpacket(dm->dev->channel, &version_req, | |
1308 | sizeof(struct dm_version_request), | |
1309 | (unsigned long)NULL, | |
1310 | VM_PKT_DATA_INBAND, 0); | |
1311 | ||
1312 | if (ret) | |
1313 | goto version_error; | |
1314 | ||
1315 | return; | |
1316 | ||
1317 | version_error: | |
1318 | dm->state = DM_INIT_ERROR; | |
1319 | complete(&dm->host_event); | |
1320 | } | |
1321 | ||
1322 | static void cap_resp(struct hv_dynmem_device *dm, | |
1323 | struct dm_capabilities_resp_msg *cap_resp) | |
1324 | { | |
1325 | if (!cap_resp->is_accepted) { | |
1326 | pr_info("Capabilities not accepted by host\n"); | |
1327 | dm->state = DM_INIT_ERROR; | |
1328 | } | |
1329 | complete(&dm->host_event); | |
1330 | } | |
1331 | ||
1332 | static void balloon_onchannelcallback(void *context) | |
1333 | { | |
1334 | struct hv_device *dev = context; | |
1335 | u32 recvlen; | |
1336 | u64 requestid; | |
1337 | struct dm_message *dm_msg; | |
1338 | struct dm_header *dm_hdr; | |
1339 | struct hv_dynmem_device *dm = hv_get_drvdata(dev); | |
6571b2da | 1340 | struct dm_balloon *bal_msg; |
c51af826 S |
1341 | struct dm_hot_add *ha_msg; |
1342 | union dm_mem_page_range *ha_pg_range; | |
1cac8cd4 | 1343 | union dm_mem_page_range *ha_region; |
9aa8b50b S |
1344 | |
1345 | memset(recv_buffer, 0, sizeof(recv_buffer)); | |
1346 | vmbus_recvpacket(dev->channel, recv_buffer, | |
1347 | PAGE_SIZE, &recvlen, &requestid); | |
1348 | ||
1349 | if (recvlen > 0) { | |
1350 | dm_msg = (struct dm_message *)recv_buffer; | |
1351 | dm_hdr = &dm_msg->hdr; | |
1352 | ||
1353 | switch (dm_hdr->type) { | |
1354 | case DM_VERSION_RESPONSE: | |
1355 | version_resp(dm, | |
1356 | (struct dm_version_response *)dm_msg); | |
1357 | break; | |
1358 | ||
1359 | case DM_CAPABILITIES_RESPONSE: | |
1360 | cap_resp(dm, | |
1361 | (struct dm_capabilities_resp_msg *)dm_msg); | |
1362 | break; | |
1363 | ||
1364 | case DM_BALLOON_REQUEST: | |
6571b2da S |
1365 | if (dm->state == DM_BALLOON_UP) |
1366 | pr_warn("Currently ballooning\n"); | |
1367 | bal_msg = (struct dm_balloon *)recv_buffer; | |
9aa8b50b | 1368 | dm->state = DM_BALLOON_UP; |
6571b2da S |
1369 | dm_device.balloon_wrk.num_pages = bal_msg->num_pages; |
1370 | schedule_work(&dm_device.balloon_wrk.wrk); | |
9aa8b50b S |
1371 | break; |
1372 | ||
1373 | case DM_UNBALLOON_REQUEST: | |
1374 | dm->state = DM_BALLOON_DOWN; | |
1375 | balloon_down(dm, | |
1376 | (struct dm_unballoon_request *)recv_buffer); | |
1377 | break; | |
1378 | ||
1379 | case DM_MEM_HOT_ADD_REQUEST: | |
c51af826 S |
1380 | if (dm->state == DM_HOT_ADD) |
1381 | pr_warn("Currently hot-adding\n"); | |
9aa8b50b | 1382 | dm->state = DM_HOT_ADD; |
c51af826 | 1383 | ha_msg = (struct dm_hot_add *)recv_buffer; |
1cac8cd4 S |
1384 | if (ha_msg->hdr.size == sizeof(struct dm_hot_add)) { |
1385 | /* | |
1386 | * This is a normal hot-add request specifying | |
1387 | * hot-add memory. | |
1388 | */ | |
1389 | ha_pg_range = &ha_msg->range; | |
1390 | dm->ha_wrk.ha_page_range = *ha_pg_range; | |
1391 | dm->ha_wrk.ha_region_range.page_range = 0; | |
1392 | } else { | |
1393 | /* | |
1394 | * Host is specifying that we first hot-add | |
1395 | * a region and then partially populate this | |
1396 | * region. | |
1397 | */ | |
1398 | dm->host_specified_ha_region = true; | |
1399 | ha_pg_range = &ha_msg->range; | |
1400 | ha_region = &ha_pg_range[1]; | |
1401 | dm->ha_wrk.ha_page_range = *ha_pg_range; | |
1402 | dm->ha_wrk.ha_region_range = *ha_region; | |
1403 | } | |
c51af826 | 1404 | schedule_work(&dm_device.ha_wrk.wrk); |
9aa8b50b S |
1405 | break; |
1406 | ||
1407 | case DM_INFO_MESSAGE: | |
1408 | process_info(dm, (struct dm_info_msg *)dm_msg); | |
1409 | break; | |
1410 | ||
1411 | default: | |
1412 | pr_err("Unhandled message: type: %d\n", dm_hdr->type); | |
1413 | ||
1414 | } | |
1415 | } | |
1416 | ||
1417 | } | |
1418 | ||
1419 | static int balloon_probe(struct hv_device *dev, | |
1420 | const struct hv_vmbus_device_id *dev_id) | |
1421 | { | |
b057b3ad NMG |
1422 | int ret; |
1423 | unsigned long t; | |
9aa8b50b S |
1424 | struct dm_version_request version_req; |
1425 | struct dm_capabilities cap_msg; | |
1426 | ||
1427 | do_hot_add = hot_add; | |
1428 | ||
1429 | /* | |
1430 | * First allocate a send buffer. | |
1431 | */ | |
1432 | ||
1433 | send_buffer = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
1434 | if (!send_buffer) | |
1435 | return -ENOMEM; | |
1436 | ||
1437 | ret = vmbus_open(dev->channel, dm_ring_size, dm_ring_size, NULL, 0, | |
1438 | balloon_onchannelcallback, dev); | |
1439 | ||
1440 | if (ret) | |
33080c1c | 1441 | goto probe_error0; |
9aa8b50b S |
1442 | |
1443 | dm_device.dev = dev; | |
1444 | dm_device.state = DM_INITIALIZING; | |
1445 | dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN7; | |
1446 | init_completion(&dm_device.host_event); | |
1447 | init_completion(&dm_device.config_event); | |
1cac8cd4 | 1448 | INIT_LIST_HEAD(&dm_device.ha_region_list); |
22f88475 | 1449 | mutex_init(&dm_device.ha_region_mutex); |
6571b2da | 1450 | INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up); |
c51af826 | 1451 | INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req); |
1cac8cd4 | 1452 | dm_device.host_specified_ha_region = false; |
9aa8b50b S |
1453 | |
1454 | dm_device.thread = | |
1455 | kthread_run(dm_thread_func, &dm_device, "hv_balloon"); | |
1456 | if (IS_ERR(dm_device.thread)) { | |
1457 | ret = PTR_ERR(dm_device.thread); | |
33080c1c | 1458 | goto probe_error1; |
9aa8b50b S |
1459 | } |
1460 | ||
1cac8cd4 S |
1461 | #ifdef CONFIG_MEMORY_HOTPLUG |
1462 | set_online_page_callback(&hv_online_page); | |
22f88475 | 1463 | register_memory_notifier(&hv_memory_nb); |
1cac8cd4 S |
1464 | #endif |
1465 | ||
9aa8b50b S |
1466 | hv_set_drvdata(dev, &dm_device); |
1467 | /* | |
1468 | * Initiate the hand shake with the host and negotiate | |
1469 | * a version that the host can support. We start with the | |
1470 | * highest version number and go down if the host cannot | |
1471 | * support it. | |
1472 | */ | |
1473 | memset(&version_req, 0, sizeof(struct dm_version_request)); | |
1474 | version_req.hdr.type = DM_VERSION_REQUEST; | |
1475 | version_req.hdr.size = sizeof(struct dm_version_request); | |
1476 | version_req.hdr.trans_id = atomic_inc_return(&trans_id); | |
1477 | version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN8; | |
1478 | version_req.is_last_attempt = 0; | |
1479 | ||
1480 | ret = vmbus_sendpacket(dev->channel, &version_req, | |
1481 | sizeof(struct dm_version_request), | |
1482 | (unsigned long)NULL, | |
7a64b864 | 1483 | VM_PKT_DATA_INBAND, 0); |
9aa8b50b | 1484 | if (ret) |
33080c1c | 1485 | goto probe_error2; |
9aa8b50b S |
1486 | |
1487 | t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ); | |
1488 | if (t == 0) { | |
1489 | ret = -ETIMEDOUT; | |
33080c1c | 1490 | goto probe_error2; |
9aa8b50b S |
1491 | } |
1492 | ||
1493 | /* | |
1494 | * If we could not negotiate a compatible version with the host | |
1495 | * fail the probe function. | |
1496 | */ | |
1497 | if (dm_device.state == DM_INIT_ERROR) { | |
1498 | ret = -ETIMEDOUT; | |
33080c1c | 1499 | goto probe_error2; |
9aa8b50b S |
1500 | } |
1501 | /* | |
1502 | * Now submit our capabilities to the host. | |
1503 | */ | |
1504 | memset(&cap_msg, 0, sizeof(struct dm_capabilities)); | |
1505 | cap_msg.hdr.type = DM_CAPABILITIES_REPORT; | |
1506 | cap_msg.hdr.size = sizeof(struct dm_capabilities); | |
1507 | cap_msg.hdr.trans_id = atomic_inc_return(&trans_id); | |
1508 | ||
1509 | cap_msg.caps.cap_bits.balloon = 1; | |
9aa8b50b S |
1510 | cap_msg.caps.cap_bits.hot_add = 1; |
1511 | ||
647965a2 S |
1512 | /* |
1513 | * Specify our alignment requirements as it relates | |
1514 | * memory hot-add. Specify 128MB alignment. | |
1515 | */ | |
1516 | cap_msg.caps.cap_bits.hot_add_alignment = 7; | |
1517 | ||
9aa8b50b S |
1518 | /* |
1519 | * Currently the host does not use these | |
1520 | * values and we set them to what is done in the | |
1521 | * Windows driver. | |
1522 | */ | |
1523 | cap_msg.min_page_cnt = 0; | |
1524 | cap_msg.max_page_number = -1; | |
1525 | ||
1526 | ret = vmbus_sendpacket(dev->channel, &cap_msg, | |
1527 | sizeof(struct dm_capabilities), | |
1528 | (unsigned long)NULL, | |
7a64b864 | 1529 | VM_PKT_DATA_INBAND, 0); |
9aa8b50b | 1530 | if (ret) |
33080c1c | 1531 | goto probe_error2; |
9aa8b50b S |
1532 | |
1533 | t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ); | |
1534 | if (t == 0) { | |
1535 | ret = -ETIMEDOUT; | |
33080c1c | 1536 | goto probe_error2; |
9aa8b50b S |
1537 | } |
1538 | ||
1539 | /* | |
1540 | * If the host does not like our capabilities, | |
1541 | * fail the probe function. | |
1542 | */ | |
1543 | if (dm_device.state == DM_INIT_ERROR) { | |
1544 | ret = -ETIMEDOUT; | |
33080c1c | 1545 | goto probe_error2; |
9aa8b50b S |
1546 | } |
1547 | ||
1548 | dm_device.state = DM_INITIALIZED; | |
1549 | ||
1550 | return 0; | |
1551 | ||
33080c1c | 1552 | probe_error2: |
1cac8cd4 S |
1553 | #ifdef CONFIG_MEMORY_HOTPLUG |
1554 | restore_online_page_callback(&hv_online_page); | |
1555 | #endif | |
9aa8b50b S |
1556 | kthread_stop(dm_device.thread); |
1557 | ||
33080c1c | 1558 | probe_error1: |
9aa8b50b | 1559 | vmbus_close(dev->channel); |
33080c1c S |
1560 | probe_error0: |
1561 | kfree(send_buffer); | |
9aa8b50b S |
1562 | return ret; |
1563 | } | |
1564 | ||
1565 | static int balloon_remove(struct hv_device *dev) | |
1566 | { | |
1567 | struct hv_dynmem_device *dm = hv_get_drvdata(dev); | |
1cac8cd4 S |
1568 | struct list_head *cur, *tmp; |
1569 | struct hv_hotadd_state *has; | |
9aa8b50b S |
1570 | |
1571 | if (dm->num_pages_ballooned != 0) | |
1572 | pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned); | |
1573 | ||
6571b2da | 1574 | cancel_work_sync(&dm->balloon_wrk.wrk); |
c51af826 | 1575 | cancel_work_sync(&dm->ha_wrk.wrk); |
1cac8cd4 | 1576 | |
9aa8b50b S |
1577 | vmbus_close(dev->channel); |
1578 | kthread_stop(dm->thread); | |
33080c1c | 1579 | kfree(send_buffer); |
1cac8cd4 S |
1580 | #ifdef CONFIG_MEMORY_HOTPLUG |
1581 | restore_online_page_callback(&hv_online_page); | |
22f88475 | 1582 | unregister_memory_notifier(&hv_memory_nb); |
1cac8cd4 S |
1583 | #endif |
1584 | list_for_each_safe(cur, tmp, &dm->ha_region_list) { | |
1585 | has = list_entry(cur, struct hv_hotadd_state, list); | |
1586 | list_del(&has->list); | |
1587 | kfree(has); | |
1588 | } | |
9aa8b50b S |
1589 | |
1590 | return 0; | |
1591 | } | |
1592 | ||
1593 | static const struct hv_vmbus_device_id id_table[] = { | |
1594 | /* Dynamic Memory Class ID */ | |
1595 | /* 525074DC-8985-46e2-8057-A307DC18A502 */ | |
d13984e5 | 1596 | { HV_DM_GUID, }, |
9aa8b50b S |
1597 | { }, |
1598 | }; | |
1599 | ||
1600 | MODULE_DEVICE_TABLE(vmbus, id_table); | |
1601 | ||
1602 | static struct hv_driver balloon_drv = { | |
1603 | .name = "hv_balloon", | |
1604 | .id_table = id_table, | |
1605 | .probe = balloon_probe, | |
1606 | .remove = balloon_remove, | |
1607 | }; | |
1608 | ||
1609 | static int __init init_balloon_drv(void) | |
1610 | { | |
1611 | ||
1612 | return vmbus_driver_register(&balloon_drv); | |
1613 | } | |
1614 | ||
9aa8b50b | 1615 | module_init(init_balloon_drv); |
9aa8b50b S |
1616 | |
1617 | MODULE_DESCRIPTION("Hyper-V Balloon"); | |
9aa8b50b | 1618 | MODULE_LICENSE("GPL"); |