1
2
3
4
5
6
7
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#include <linux/kernel.h>
12#include <linux/jiffies.h>
13#include <linux/mman.h>
14#include <linux/delay.h>
15#include <linux/init.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18#include <linux/kthread.h>
19#include <linux/completion.h>
20#include <linux/memory_hotplug.h>
21#include <linux/memory.h>
22#include <linux/notifier.h>
23#include <linux/percpu_counter.h>
24#include <linux/page_reporting.h>
25
26#include <linux/hyperv.h>
27#include <asm/hyperv-tlfs.h>
28
29#include <asm/mshyperv.h>
30
31#define CREATE_TRACE_POINTS
32#include "hv_trace_balloon.h"
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55#define DYNMEM_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor)))
56#define DYNMEM_MAJOR_VERSION(Version) ((__u32)(Version) >> 16)
57#define DYNMEM_MINOR_VERSION(Version) ((__u32)(Version) & 0xff)
58
59enum {
60 DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3),
61 DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0),
62 DYNMEM_PROTOCOL_VERSION_3 = DYNMEM_MAKE_VERSION(2, 0),
63
64 DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1,
65 DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2,
66 DYNMEM_PROTOCOL_VERSION_WIN10 = DYNMEM_PROTOCOL_VERSION_3,
67
68 DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN10
69};
70
71
72
73
74
75
76
77enum dm_message_type {
78
79
80
81 DM_ERROR = 0,
82 DM_VERSION_REQUEST = 1,
83 DM_VERSION_RESPONSE = 2,
84 DM_CAPABILITIES_REPORT = 3,
85 DM_CAPABILITIES_RESPONSE = 4,
86 DM_STATUS_REPORT = 5,
87 DM_BALLOON_REQUEST = 6,
88 DM_BALLOON_RESPONSE = 7,
89 DM_UNBALLOON_REQUEST = 8,
90 DM_UNBALLOON_RESPONSE = 9,
91 DM_MEM_HOT_ADD_REQUEST = 10,
92 DM_MEM_HOT_ADD_RESPONSE = 11,
93 DM_VERSION_03_MAX = 11,
94
95
96
97 DM_INFO_MESSAGE = 12,
98 DM_VERSION_1_MAX = 12
99};
100
101
102
103
104
105
106
107union dm_version {
108 struct {
109 __u16 minor_version;
110 __u16 major_version;
111 };
112 __u32 version;
113} __packed;
114
115
116union dm_caps {
117 struct {
118 __u64 balloon:1;
119 __u64 hot_add:1;
120
121
122
123
124
125
126 __u64 hot_add_alignment:4;
127 __u64 reservedz:58;
128 } cap_bits;
129 __u64 caps;
130} __packed;
131
132union dm_mem_page_range {
133 struct {
134
135
136
137
138
139 __u64 start_page:40;
140
141
142
143 __u64 page_cnt:24;
144 } finfo;
145 __u64 page_range;
146} __packed;
147
148
149
150
151
152
153
154
155
156
157
158struct dm_header {
159 __u16 type;
160 __u16 size;
161 __u32 trans_id;
162} __packed;
163
164
165
166
167
168
169struct dm_message {
170 struct dm_header hdr;
171 __u8 data[];
172} __packed;
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189struct dm_version_request {
190 struct dm_header hdr;
191 union dm_version version;
192 __u32 is_last_attempt:1;
193 __u32 reservedz:31;
194} __packed;
195
196
197
198
199
200
201
202
203
204
205
206
207struct dm_version_response {
208 struct dm_header hdr;
209 __u64 is_accepted:1;
210 __u64 reservedz:63;
211} __packed;
212
213
214
215
216
217
218struct dm_capabilities {
219 struct dm_header hdr;
220 union dm_caps caps;
221 __u64 min_page_cnt;
222 __u64 max_page_number;
223} __packed;
224
225
226
227
228
229
230
231
232
233
234
235struct dm_capabilities_resp_msg {
236 struct dm_header hdr;
237 __u64 is_accepted:1;
238 __u64 reservedz:63;
239} __packed;
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261struct dm_status {
262 struct dm_header hdr;
263 __u64 num_avail;
264 __u64 num_committed;
265 __u64 page_file_size;
266 __u64 zero_free;
267 __u32 page_file_writes;
268 __u32 io_diff;
269} __packed;
270
271
272
273
274
275
276
277
278
279
280struct dm_balloon {
281 struct dm_header hdr;
282 __u32 num_pages;
283 __u32 reservedz;
284} __packed;
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301struct dm_balloon_response {
302 struct dm_header hdr;
303 __u32 reservedz;
304 __u32 more_pages:1;
305 __u32 range_count:31;
306 union dm_mem_page_range range_array[];
307} __packed;
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324struct dm_unballoon_request {
325 struct dm_header hdr;
326 __u32 more_pages:1;
327 __u32 reservedz:31;
328 __u32 range_count;
329 union dm_mem_page_range range_array[];
330} __packed;
331
332
333
334
335
336
337
338struct dm_unballoon_response {
339 struct dm_header hdr;
340} __packed;
341
342
343
344
345
346
347
348
349
350struct dm_hot_add {
351 struct dm_header hdr;
352 union dm_mem_page_range range;
353} __packed;
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375struct dm_hot_add_response {
376 struct dm_header hdr;
377 __u32 page_count;
378 __u32 result;
379} __packed;
380
381
382
383
384
385enum dm_info_type {
386 INFO_TYPE_MAX_PAGE_CNT = 0,
387 MAX_INFO_TYPE
388};
389
390
391
392
393
394
395struct dm_info_header {
396 enum dm_info_type type;
397 __u32 data_size;
398} __packed;
399
400
401
402
403
404
405
406
407
408
409struct dm_info_msg {
410 struct dm_header hdr;
411 __u32 reserved;
412 __u32 info_size;
413 __u8 info[];
414};
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432struct hv_hotadd_state {
433 struct list_head list;
434 unsigned long start_pfn;
435 unsigned long covered_start_pfn;
436 unsigned long covered_end_pfn;
437 unsigned long ha_end_pfn;
438 unsigned long end_pfn;
439
440
441
442 struct list_head gap_list;
443};
444
445struct hv_hotadd_gap {
446 struct list_head list;
447 unsigned long start_pfn;
448 unsigned long end_pfn;
449};
450
451struct balloon_state {
452 __u32 num_pages;
453 struct work_struct wrk;
454};
455
456struct hot_add_wrk {
457 union dm_mem_page_range ha_page_range;
458 union dm_mem_page_range ha_region_range;
459 struct work_struct wrk;
460};
461
462static bool allow_hibernation;
463static bool hot_add = true;
464static bool do_hot_add;
465
466
467
468
469static uint pressure_report_delay = 45;
470
471
472
473
474static unsigned long last_post_time;
475
476module_param(hot_add, bool, (S_IRUGO | S_IWUSR));
477MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add");
478
479module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR));
480MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure");
481static atomic_t trans_id = ATOMIC_INIT(0);
482
483static int dm_ring_size = 20 * 1024;
484
485
486
487
488
489enum hv_dm_state {
490 DM_INITIALIZING = 0,
491 DM_INITIALIZED,
492 DM_BALLOON_UP,
493 DM_BALLOON_DOWN,
494 DM_HOT_ADD,
495 DM_INIT_ERROR
496};
497
498
499static __u8 recv_buffer[HV_HYP_PAGE_SIZE];
500static __u8 balloon_up_send_buffer[HV_HYP_PAGE_SIZE];
501#define PAGES_IN_2M (2 * 1024 * 1024 / PAGE_SIZE)
502#define HA_CHUNK (128 * 1024 * 1024 / PAGE_SIZE)
503
504struct hv_dynmem_device {
505 struct hv_device *dev;
506 enum hv_dm_state state;
507 struct completion host_event;
508 struct completion config_event;
509
510
511
512
513 unsigned int num_pages_ballooned;
514 unsigned int num_pages_onlined;
515 unsigned int num_pages_added;
516
517
518
519
520 struct balloon_state balloon_wrk;
521
522
523
524
525 struct hot_add_wrk ha_wrk;
526
527
528
529
530
531 bool host_specified_ha_region;
532
533
534
535
536 struct completion ol_waitevent;
537
538
539
540
541
542
543 struct task_struct *thread;
544
545
546
547
548
549 spinlock_t ha_lock;
550
551
552
553
554 struct list_head ha_region_list;
555
556
557
558
559
560
561 __u32 next_version;
562
563
564
565
566 __u32 version;
567
568 struct page_reporting_dev_info pr_dev_info;
569};
570
571static struct hv_dynmem_device dm_device;
572
573static void post_status(struct hv_dynmem_device *dm);
574
575#ifdef CONFIG_MEMORY_HOTPLUG
576static inline bool has_pfn_is_backed(struct hv_hotadd_state *has,
577 unsigned long pfn)
578{
579 struct hv_hotadd_gap *gap;
580
581
582 if ((pfn < has->covered_start_pfn) || (pfn >= has->covered_end_pfn))
583 return false;
584
585
586 list_for_each_entry(gap, &has->gap_list, list) {
587 if ((pfn >= gap->start_pfn) && (pfn < gap->end_pfn))
588 return false;
589 }
590
591 return true;
592}
593
594static unsigned long hv_page_offline_check(unsigned long start_pfn,
595 unsigned long nr_pages)
596{
597 unsigned long pfn = start_pfn, count = 0;
598 struct hv_hotadd_state *has;
599 bool found;
600
601 while (pfn < start_pfn + nr_pages) {
602
603
604
605
606 found = false;
607 list_for_each_entry(has, &dm_device.ha_region_list, list) {
608 while ((pfn >= has->start_pfn) &&
609 (pfn < has->end_pfn) &&
610 (pfn < start_pfn + nr_pages)) {
611 found = true;
612 if (has_pfn_is_backed(has, pfn))
613 count++;
614 pfn++;
615 }
616 }
617
618
619
620
621
622
623 if (!found)
624 pfn++;
625 }
626
627 return count;
628}
629
630static int hv_memory_notifier(struct notifier_block *nb, unsigned long val,
631 void *v)
632{
633 struct memory_notify *mem = (struct memory_notify *)v;
634 unsigned long flags, pfn_count;
635
636 switch (val) {
637 case MEM_ONLINE:
638 case MEM_CANCEL_ONLINE:
639 complete(&dm_device.ol_waitevent);
640 break;
641
642 case MEM_OFFLINE:
643 spin_lock_irqsave(&dm_device.ha_lock, flags);
644 pfn_count = hv_page_offline_check(mem->start_pfn,
645 mem->nr_pages);
646 if (pfn_count <= dm_device.num_pages_onlined) {
647 dm_device.num_pages_onlined -= pfn_count;
648 } else {
649
650
651
652
653
654 WARN_ON_ONCE(1);
655 dm_device.num_pages_onlined = 0;
656 }
657 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
658 break;
659 case MEM_GOING_ONLINE:
660 case MEM_GOING_OFFLINE:
661 case MEM_CANCEL_OFFLINE:
662 break;
663 }
664 return NOTIFY_OK;
665}
666
667static struct notifier_block hv_memory_nb = {
668 .notifier_call = hv_memory_notifier,
669 .priority = 0
670};
671
672
673static void hv_page_online_one(struct hv_hotadd_state *has, struct page *pg)
674{
675 if (!has_pfn_is_backed(has, page_to_pfn(pg))) {
676 if (!PageOffline(pg))
677 __SetPageOffline(pg);
678 return;
679 }
680 if (PageOffline(pg))
681 __ClearPageOffline(pg);
682
683
684 generic_online_page(pg, 0);
685
686 lockdep_assert_held(&dm_device.ha_lock);
687 dm_device.num_pages_onlined++;
688}
689
690static void hv_bring_pgs_online(struct hv_hotadd_state *has,
691 unsigned long start_pfn, unsigned long size)
692{
693 int i;
694
695 pr_debug("Online %lu pages starting at pfn 0x%lx\n", size, start_pfn);
696 for (i = 0; i < size; i++)
697 hv_page_online_one(has, pfn_to_page(start_pfn + i));
698}
699
700static void hv_mem_hot_add(unsigned long start, unsigned long size,
701 unsigned long pfn_count,
702 struct hv_hotadd_state *has)
703{
704 int ret = 0;
705 int i, nid;
706 unsigned long start_pfn;
707 unsigned long processed_pfn;
708 unsigned long total_pfn = pfn_count;
709 unsigned long flags;
710
711 for (i = 0; i < (size/HA_CHUNK); i++) {
712 start_pfn = start + (i * HA_CHUNK);
713
714 spin_lock_irqsave(&dm_device.ha_lock, flags);
715 has->ha_end_pfn += HA_CHUNK;
716
717 if (total_pfn > HA_CHUNK) {
718 processed_pfn = HA_CHUNK;
719 total_pfn -= HA_CHUNK;
720 } else {
721 processed_pfn = total_pfn;
722 total_pfn = 0;
723 }
724
725 has->covered_end_pfn += processed_pfn;
726 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
727
728 reinit_completion(&dm_device.ol_waitevent);
729
730 nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn));
731 ret = add_memory(nid, PFN_PHYS((start_pfn)),
732 (HA_CHUNK << PAGE_SHIFT), MHP_MERGE_RESOURCE);
733
734 if (ret) {
735 pr_err("hot_add memory failed error is %d\n", ret);
736 if (ret == -EEXIST) {
737
738
739
740
741
742
743
744 do_hot_add = false;
745 }
746 spin_lock_irqsave(&dm_device.ha_lock, flags);
747 has->ha_end_pfn -= HA_CHUNK;
748 has->covered_end_pfn -= processed_pfn;
749 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
750 break;
751 }
752
753
754
755
756
757
758
759
760
761 wait_for_completion_timeout(&dm_device.ol_waitevent, 5 * HZ);
762 post_status(&dm_device);
763 }
764}
765
766static void hv_online_page(struct page *pg, unsigned int order)
767{
768 struct hv_hotadd_state *has;
769 unsigned long flags;
770 unsigned long pfn = page_to_pfn(pg);
771
772 spin_lock_irqsave(&dm_device.ha_lock, flags);
773 list_for_each_entry(has, &dm_device.ha_region_list, list) {
774
775 if ((pfn < has->start_pfn) ||
776 (pfn + (1UL << order) > has->end_pfn))
777 continue;
778
779 hv_bring_pgs_online(has, pfn, 1UL << order);
780 break;
781 }
782 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
783}
784
785static int pfn_covered(unsigned long start_pfn, unsigned long pfn_cnt)
786{
787 struct hv_hotadd_state *has;
788 struct hv_hotadd_gap *gap;
789 unsigned long residual, new_inc;
790 int ret = 0;
791 unsigned long flags;
792
793 spin_lock_irqsave(&dm_device.ha_lock, flags);
794 list_for_each_entry(has, &dm_device.ha_region_list, list) {
795
796
797
798
799 if (start_pfn < has->start_pfn || start_pfn >= has->end_pfn)
800 continue;
801
802
803
804
805
806 if (has->covered_end_pfn != start_pfn) {
807 gap = kzalloc(sizeof(struct hv_hotadd_gap), GFP_ATOMIC);
808 if (!gap) {
809 ret = -ENOMEM;
810 break;
811 }
812
813 INIT_LIST_HEAD(&gap->list);
814 gap->start_pfn = has->covered_end_pfn;
815 gap->end_pfn = start_pfn;
816 list_add_tail(&gap->list, &has->gap_list);
817
818 has->covered_end_pfn = start_pfn;
819 }
820
821
822
823
824
825 if ((start_pfn + pfn_cnt) > has->end_pfn) {
826 residual = (start_pfn + pfn_cnt - has->end_pfn);
827
828
829
830 new_inc = (residual / HA_CHUNK) * HA_CHUNK;
831 if (residual % HA_CHUNK)
832 new_inc += HA_CHUNK;
833
834 has->end_pfn += new_inc;
835 }
836
837 ret = 1;
838 break;
839 }
840 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
841
842 return ret;
843}
844
845static unsigned long handle_pg_range(unsigned long pg_start,
846 unsigned long pg_count)
847{
848 unsigned long start_pfn = pg_start;
849 unsigned long pfn_cnt = pg_count;
850 unsigned long size;
851 struct hv_hotadd_state *has;
852 unsigned long pgs_ol = 0;
853 unsigned long old_covered_state;
854 unsigned long res = 0, flags;
855
856 pr_debug("Hot adding %lu pages starting at pfn 0x%lx.\n", pg_count,
857 pg_start);
858
859 spin_lock_irqsave(&dm_device.ha_lock, flags);
860 list_for_each_entry(has, &dm_device.ha_region_list, list) {
861
862
863
864
865 if (start_pfn < has->start_pfn || start_pfn >= has->end_pfn)
866 continue;
867
868 old_covered_state = has->covered_end_pfn;
869
870 if (start_pfn < has->ha_end_pfn) {
871
872
873
874
875
876 pgs_ol = has->ha_end_pfn - start_pfn;
877 if (pgs_ol > pfn_cnt)
878 pgs_ol = pfn_cnt;
879
880 has->covered_end_pfn += pgs_ol;
881 pfn_cnt -= pgs_ol;
882
883
884
885
886
887
888
889
890 if (start_pfn > has->start_pfn &&
891 online_section_nr(pfn_to_section_nr(start_pfn)))
892 hv_bring_pgs_online(has, start_pfn, pgs_ol);
893
894 }
895
896 if ((has->ha_end_pfn < has->end_pfn) && (pfn_cnt > 0)) {
897
898
899
900
901
902
903
904 size = (has->end_pfn - has->ha_end_pfn);
905 if (pfn_cnt <= size) {
906 size = ((pfn_cnt / HA_CHUNK) * HA_CHUNK);
907 if (pfn_cnt % HA_CHUNK)
908 size += HA_CHUNK;
909 } else {
910 pfn_cnt = size;
911 }
912 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
913 hv_mem_hot_add(has->ha_end_pfn, size, pfn_cnt, has);
914 spin_lock_irqsave(&dm_device.ha_lock, flags);
915 }
916
917
918
919
920 res = has->covered_end_pfn - old_covered_state;
921 break;
922 }
923 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
924
925 return res;
926}
927
928static unsigned long process_hot_add(unsigned long pg_start,
929 unsigned long pfn_cnt,
930 unsigned long rg_start,
931 unsigned long rg_size)
932{
933 struct hv_hotadd_state *ha_region = NULL;
934 int covered;
935 unsigned long flags;
936
937 if (pfn_cnt == 0)
938 return 0;
939
940 if (!dm_device.host_specified_ha_region) {
941 covered = pfn_covered(pg_start, pfn_cnt);
942 if (covered < 0)
943 return 0;
944
945 if (covered)
946 goto do_pg_range;
947 }
948
949
950
951
952
953 if (rg_size != 0) {
954 ha_region = kzalloc(sizeof(struct hv_hotadd_state), GFP_KERNEL);
955 if (!ha_region)
956 return 0;
957
958 INIT_LIST_HEAD(&ha_region->list);
959 INIT_LIST_HEAD(&ha_region->gap_list);
960
961 ha_region->start_pfn = rg_start;
962 ha_region->ha_end_pfn = rg_start;
963 ha_region->covered_start_pfn = pg_start;
964 ha_region->covered_end_pfn = pg_start;
965 ha_region->end_pfn = rg_start + rg_size;
966
967 spin_lock_irqsave(&dm_device.ha_lock, flags);
968 list_add_tail(&ha_region->list, &dm_device.ha_region_list);
969 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
970 }
971
972do_pg_range:
973
974
975
976
977 return handle_pg_range(pg_start, pfn_cnt);
978}
979
980#endif
981
982static void hot_add_req(struct work_struct *dummy)
983{
984 struct dm_hot_add_response resp;
985#ifdef CONFIG_MEMORY_HOTPLUG
986 unsigned long pg_start, pfn_cnt;
987 unsigned long rg_start, rg_sz;
988#endif
989 struct hv_dynmem_device *dm = &dm_device;
990
991 memset(&resp, 0, sizeof(struct dm_hot_add_response));
992 resp.hdr.type = DM_MEM_HOT_ADD_RESPONSE;
993 resp.hdr.size = sizeof(struct dm_hot_add_response);
994
995#ifdef CONFIG_MEMORY_HOTPLUG
996 pg_start = dm->ha_wrk.ha_page_range.finfo.start_page;
997 pfn_cnt = dm->ha_wrk.ha_page_range.finfo.page_cnt;
998
999 rg_start = dm->ha_wrk.ha_region_range.finfo.start_page;
1000 rg_sz = dm->ha_wrk.ha_region_range.finfo.page_cnt;
1001
1002 if ((rg_start == 0) && (!dm->host_specified_ha_region)) {
1003 unsigned long region_size;
1004 unsigned long region_start;
1005
1006
1007
1008
1009
1010
1011
1012
1013 region_size = (pfn_cnt / HA_CHUNK) * HA_CHUNK;
1014 if (pfn_cnt % HA_CHUNK)
1015 region_size += HA_CHUNK;
1016
1017 region_start = (pg_start / HA_CHUNK) * HA_CHUNK;
1018
1019 rg_start = region_start;
1020 rg_sz = region_size;
1021 }
1022
1023 if (do_hot_add)
1024 resp.page_count = process_hot_add(pg_start, pfn_cnt,
1025 rg_start, rg_sz);
1026
1027 dm->num_pages_added += resp.page_count;
1028#endif
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045 if (resp.page_count > 0)
1046 resp.result = 1;
1047 else if (!do_hot_add)
1048 resp.result = 1;
1049 else
1050 resp.result = 0;
1051
1052 if (!do_hot_add || resp.page_count == 0) {
1053 if (!allow_hibernation)
1054 pr_err("Memory hot add failed\n");
1055 else
1056 pr_info("Ignore hot-add request!\n");
1057 }
1058
1059 dm->state = DM_INITIALIZED;
1060 resp.hdr.trans_id = atomic_inc_return(&trans_id);
1061 vmbus_sendpacket(dm->dev->channel, &resp,
1062 sizeof(struct dm_hot_add_response),
1063 (unsigned long)NULL,
1064 VM_PKT_DATA_INBAND, 0);
1065}
1066
1067static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
1068{
1069 struct dm_info_header *info_hdr;
1070
1071 info_hdr = (struct dm_info_header *)msg->info;
1072
1073 switch (info_hdr->type) {
1074 case INFO_TYPE_MAX_PAGE_CNT:
1075 if (info_hdr->data_size == sizeof(__u64)) {
1076 __u64 *max_page_count = (__u64 *)&info_hdr[1];
1077
1078 pr_info("Max. dynamic memory size: %llu MB\n",
1079 (*max_page_count) >> (20 - HV_HYP_PAGE_SHIFT));
1080 }
1081
1082 break;
1083 default:
1084 pr_warn("Received Unknown type: %d\n", info_hdr->type);
1085 }
1086}
1087
1088static unsigned long compute_balloon_floor(void)
1089{
1090 unsigned long min_pages;
1091 unsigned long nr_pages = totalram_pages();
1092#define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT))
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104 if (nr_pages < MB2PAGES(128))
1105 min_pages = MB2PAGES(8) + (nr_pages >> 1);
1106 else if (nr_pages < MB2PAGES(512))
1107 min_pages = MB2PAGES(40) + (nr_pages >> 2);
1108 else if (nr_pages < MB2PAGES(2048))
1109 min_pages = MB2PAGES(104) + (nr_pages >> 3);
1110 else if (nr_pages < MB2PAGES(8192))
1111 min_pages = MB2PAGES(232) + (nr_pages >> 4);
1112 else
1113 min_pages = MB2PAGES(488) + (nr_pages >> 5);
1114#undef MB2PAGES
1115 return min_pages;
1116}
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128static void post_status(struct hv_dynmem_device *dm)
1129{
1130 struct dm_status status;
1131 unsigned long now = jiffies;
1132 unsigned long last_post = last_post_time;
1133
1134 if (pressure_report_delay > 0) {
1135 --pressure_report_delay;
1136 return;
1137 }
1138
1139 if (!time_after(now, (last_post_time + HZ)))
1140 return;
1141
1142 memset(&status, 0, sizeof(struct dm_status));
1143 status.hdr.type = DM_STATUS_REPORT;
1144 status.hdr.size = sizeof(struct dm_status);
1145 status.hdr.trans_id = atomic_inc_return(&trans_id);
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157 status.num_avail = si_mem_available();
1158 status.num_committed = vm_memory_committed() +
1159 dm->num_pages_ballooned +
1160 (dm->num_pages_added > dm->num_pages_onlined ?
1161 dm->num_pages_added - dm->num_pages_onlined : 0) +
1162 compute_balloon_floor();
1163
1164 trace_balloon_status(status.num_avail, status.num_committed,
1165 vm_memory_committed(), dm->num_pages_ballooned,
1166 dm->num_pages_added, dm->num_pages_onlined);
1167
1168
1169
1170
1171
1172 if (status.hdr.trans_id != atomic_read(&trans_id))
1173 return;
1174
1175
1176
1177
1178
1179 if (last_post != last_post_time)
1180 return;
1181
1182 last_post_time = jiffies;
1183 vmbus_sendpacket(dm->dev->channel, &status,
1184 sizeof(struct dm_status),
1185 (unsigned long)NULL,
1186 VM_PKT_DATA_INBAND, 0);
1187
1188}
1189
1190static void free_balloon_pages(struct hv_dynmem_device *dm,
1191 union dm_mem_page_range *range_array)
1192{
1193 int num_pages = range_array->finfo.page_cnt;
1194 __u64 start_frame = range_array->finfo.start_page;
1195 struct page *pg;
1196 int i;
1197
1198 for (i = 0; i < num_pages; i++) {
1199 pg = pfn_to_page(i + start_frame);
1200 __ClearPageOffline(pg);
1201 __free_page(pg);
1202 dm->num_pages_ballooned--;
1203 adjust_managed_page_count(pg, 1);
1204 }
1205}
1206
1207
1208
1209static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm,
1210 unsigned int num_pages,
1211 struct dm_balloon_response *bl_resp,
1212 int alloc_unit)
1213{
1214 unsigned int i, j;
1215 struct page *pg;
1216
1217 for (i = 0; i < num_pages / alloc_unit; i++) {
1218 if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) >
1219 HV_HYP_PAGE_SIZE)
1220 return i * alloc_unit;
1221
1222
1223
1224
1225
1226 pg = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY |
1227 __GFP_NOMEMALLOC | __GFP_NOWARN,
1228 get_order(alloc_unit << PAGE_SHIFT));
1229
1230 if (!pg)
1231 return i * alloc_unit;
1232
1233 dm->num_pages_ballooned += alloc_unit;
1234
1235
1236
1237
1238
1239
1240 if (alloc_unit != 1)
1241 split_page(pg, get_order(alloc_unit << PAGE_SHIFT));
1242
1243
1244 for (j = 0; j < alloc_unit; j++) {
1245 __SetPageOffline(pg + j);
1246 adjust_managed_page_count(pg + j, -1);
1247 }
1248
1249 bl_resp->range_count++;
1250 bl_resp->range_array[i].finfo.start_page =
1251 page_to_pfn(pg);
1252 bl_resp->range_array[i].finfo.page_cnt = alloc_unit;
1253 bl_resp->hdr.size += sizeof(union dm_mem_page_range);
1254
1255 }
1256
1257 return i * alloc_unit;
1258}
1259
1260static void balloon_up(struct work_struct *dummy)
1261{
1262 unsigned int num_pages = dm_device.balloon_wrk.num_pages;
1263 unsigned int num_ballooned = 0;
1264 struct dm_balloon_response *bl_resp;
1265 int alloc_unit;
1266 int ret;
1267 bool done = false;
1268 int i;
1269 long avail_pages;
1270 unsigned long floor;
1271
1272
1273
1274
1275
1276 alloc_unit = PAGES_IN_2M;
1277
1278 avail_pages = si_mem_available();
1279 floor = compute_balloon_floor();
1280
1281
1282 if (avail_pages < num_pages || avail_pages - num_pages < floor) {
1283 pr_info("Balloon request will be partially fulfilled. %s\n",
1284 avail_pages < num_pages ? "Not enough memory." :
1285 "Balloon floor reached.");
1286
1287 num_pages = avail_pages > floor ? (avail_pages - floor) : 0;
1288 }
1289
1290 while (!done) {
1291 memset(balloon_up_send_buffer, 0, HV_HYP_PAGE_SIZE);
1292 bl_resp = (struct dm_balloon_response *)balloon_up_send_buffer;
1293 bl_resp->hdr.type = DM_BALLOON_RESPONSE;
1294 bl_resp->hdr.size = sizeof(struct dm_balloon_response);
1295 bl_resp->more_pages = 1;
1296
1297 num_pages -= num_ballooned;
1298 num_ballooned = alloc_balloon_pages(&dm_device, num_pages,
1299 bl_resp, alloc_unit);
1300
1301 if (alloc_unit != 1 && num_ballooned == 0) {
1302 alloc_unit = 1;
1303 continue;
1304 }
1305
1306 if (num_ballooned == 0 || num_ballooned == num_pages) {
1307 pr_debug("Ballooned %u out of %u requested pages.\n",
1308 num_pages, dm_device.balloon_wrk.num_pages);
1309
1310 bl_resp->more_pages = 0;
1311 done = true;
1312 dm_device.state = DM_INITIALIZED;
1313 }
1314
1315
1316
1317
1318
1319
1320
1321 do {
1322 bl_resp->hdr.trans_id = atomic_inc_return(&trans_id);
1323 ret = vmbus_sendpacket(dm_device.dev->channel,
1324 bl_resp,
1325 bl_resp->hdr.size,
1326 (unsigned long)NULL,
1327 VM_PKT_DATA_INBAND, 0);
1328
1329 if (ret == -EAGAIN)
1330 msleep(20);
1331 post_status(&dm_device);
1332 } while (ret == -EAGAIN);
1333
1334 if (ret) {
1335
1336
1337
1338 pr_err("Balloon response failed\n");
1339
1340 for (i = 0; i < bl_resp->range_count; i++)
1341 free_balloon_pages(&dm_device,
1342 &bl_resp->range_array[i]);
1343
1344 done = true;
1345 }
1346 }
1347
1348}
1349
1350static void balloon_down(struct hv_dynmem_device *dm,
1351 struct dm_unballoon_request *req)
1352{
1353 union dm_mem_page_range *range_array = req->range_array;
1354 int range_count = req->range_count;
1355 struct dm_unballoon_response resp;
1356 int i;
1357 unsigned int prev_pages_ballooned = dm->num_pages_ballooned;
1358
1359 for (i = 0; i < range_count; i++) {
1360 free_balloon_pages(dm, &range_array[i]);
1361 complete(&dm_device.config_event);
1362 }
1363
1364 pr_debug("Freed %u ballooned pages.\n",
1365 prev_pages_ballooned - dm->num_pages_ballooned);
1366
1367 if (req->more_pages == 1)
1368 return;
1369
1370 memset(&resp, 0, sizeof(struct dm_unballoon_response));
1371 resp.hdr.type = DM_UNBALLOON_RESPONSE;
1372 resp.hdr.trans_id = atomic_inc_return(&trans_id);
1373 resp.hdr.size = sizeof(struct dm_unballoon_response);
1374
1375 vmbus_sendpacket(dm_device.dev->channel, &resp,
1376 sizeof(struct dm_unballoon_response),
1377 (unsigned long)NULL,
1378 VM_PKT_DATA_INBAND, 0);
1379
1380 dm->state = DM_INITIALIZED;
1381}
1382
1383static void balloon_onchannelcallback(void *context);
1384
1385static int dm_thread_func(void *dm_dev)
1386{
1387 struct hv_dynmem_device *dm = dm_dev;
1388
1389 while (!kthread_should_stop()) {
1390 wait_for_completion_interruptible_timeout(
1391 &dm_device.config_event, 1*HZ);
1392
1393
1394
1395
1396 reinit_completion(&dm_device.config_event);
1397 post_status(dm);
1398 }
1399
1400 return 0;
1401}
1402
1403
1404static void version_resp(struct hv_dynmem_device *dm,
1405 struct dm_version_response *vresp)
1406{
1407 struct dm_version_request version_req;
1408 int ret;
1409
1410 if (vresp->is_accepted) {
1411
1412
1413
1414
1415
1416 complete(&dm->host_event);
1417 return;
1418 }
1419
1420
1421
1422
1423
1424
1425
1426 if (dm->next_version == 0)
1427 goto version_error;
1428
1429 memset(&version_req, 0, sizeof(struct dm_version_request));
1430 version_req.hdr.type = DM_VERSION_REQUEST;
1431 version_req.hdr.size = sizeof(struct dm_version_request);
1432 version_req.hdr.trans_id = atomic_inc_return(&trans_id);
1433 version_req.version.version = dm->next_version;
1434 dm->version = version_req.version.version;
1435
1436
1437
1438
1439
1440 switch (version_req.version.version) {
1441 case DYNMEM_PROTOCOL_VERSION_WIN8:
1442 dm->next_version = DYNMEM_PROTOCOL_VERSION_WIN7;
1443 version_req.is_last_attempt = 0;
1444 break;
1445 default:
1446 dm->next_version = 0;
1447 version_req.is_last_attempt = 1;
1448 }
1449
1450 ret = vmbus_sendpacket(dm->dev->channel, &version_req,
1451 sizeof(struct dm_version_request),
1452 (unsigned long)NULL,
1453 VM_PKT_DATA_INBAND, 0);
1454
1455 if (ret)
1456 goto version_error;
1457
1458 return;
1459
1460version_error:
1461 dm->state = DM_INIT_ERROR;
1462 complete(&dm->host_event);
1463}
1464
1465static void cap_resp(struct hv_dynmem_device *dm,
1466 struct dm_capabilities_resp_msg *cap_resp)
1467{
1468 if (!cap_resp->is_accepted) {
1469 pr_err("Capabilities not accepted by host\n");
1470 dm->state = DM_INIT_ERROR;
1471 }
1472 complete(&dm->host_event);
1473}
1474
1475static void balloon_onchannelcallback(void *context)
1476{
1477 struct hv_device *dev = context;
1478 u32 recvlen;
1479 u64 requestid;
1480 struct dm_message *dm_msg;
1481 struct dm_header *dm_hdr;
1482 struct hv_dynmem_device *dm = hv_get_drvdata(dev);
1483 struct dm_balloon *bal_msg;
1484 struct dm_hot_add *ha_msg;
1485 union dm_mem_page_range *ha_pg_range;
1486 union dm_mem_page_range *ha_region;
1487
1488 memset(recv_buffer, 0, sizeof(recv_buffer));
1489 vmbus_recvpacket(dev->channel, recv_buffer,
1490 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
1491
1492 if (recvlen > 0) {
1493 dm_msg = (struct dm_message *)recv_buffer;
1494 dm_hdr = &dm_msg->hdr;
1495
1496 switch (dm_hdr->type) {
1497 case DM_VERSION_RESPONSE:
1498 version_resp(dm,
1499 (struct dm_version_response *)dm_msg);
1500 break;
1501
1502 case DM_CAPABILITIES_RESPONSE:
1503 cap_resp(dm,
1504 (struct dm_capabilities_resp_msg *)dm_msg);
1505 break;
1506
1507 case DM_BALLOON_REQUEST:
1508 if (allow_hibernation) {
1509 pr_info("Ignore balloon-up request!\n");
1510 break;
1511 }
1512
1513 if (dm->state == DM_BALLOON_UP)
1514 pr_warn("Currently ballooning\n");
1515 bal_msg = (struct dm_balloon *)recv_buffer;
1516 dm->state = DM_BALLOON_UP;
1517 dm_device.balloon_wrk.num_pages = bal_msg->num_pages;
1518 schedule_work(&dm_device.balloon_wrk.wrk);
1519 break;
1520
1521 case DM_UNBALLOON_REQUEST:
1522 if (allow_hibernation) {
1523 pr_info("Ignore balloon-down request!\n");
1524 break;
1525 }
1526
1527 dm->state = DM_BALLOON_DOWN;
1528 balloon_down(dm,
1529 (struct dm_unballoon_request *)recv_buffer);
1530 break;
1531
1532 case DM_MEM_HOT_ADD_REQUEST:
1533 if (dm->state == DM_HOT_ADD)
1534 pr_warn("Currently hot-adding\n");
1535 dm->state = DM_HOT_ADD;
1536 ha_msg = (struct dm_hot_add *)recv_buffer;
1537 if (ha_msg->hdr.size == sizeof(struct dm_hot_add)) {
1538
1539
1540
1541
1542 dm->host_specified_ha_region = false;
1543 ha_pg_range = &ha_msg->range;
1544 dm->ha_wrk.ha_page_range = *ha_pg_range;
1545 dm->ha_wrk.ha_region_range.page_range = 0;
1546 } else {
1547
1548
1549
1550
1551
1552 dm->host_specified_ha_region = true;
1553 ha_pg_range = &ha_msg->range;
1554 ha_region = &ha_pg_range[1];
1555 dm->ha_wrk.ha_page_range = *ha_pg_range;
1556 dm->ha_wrk.ha_region_range = *ha_region;
1557 }
1558 schedule_work(&dm_device.ha_wrk.wrk);
1559 break;
1560
1561 case DM_INFO_MESSAGE:
1562 process_info(dm, (struct dm_info_msg *)dm_msg);
1563 break;
1564
1565 default:
1566 pr_warn("Unhandled message: type: %d\n", dm_hdr->type);
1567
1568 }
1569 }
1570
1571}
1572
1573
1574#define HV_MIN_PAGE_REPORTING_ORDER 9
1575#define HV_MIN_PAGE_REPORTING_LEN (HV_HYP_PAGE_SIZE << HV_MIN_PAGE_REPORTING_ORDER)
1576static int hv_free_page_report(struct page_reporting_dev_info *pr_dev_info,
1577 struct scatterlist *sgl, unsigned int nents)
1578{
1579 unsigned long flags;
1580 struct hv_memory_hint *hint;
1581 int i;
1582 u64 status;
1583 struct scatterlist *sg;
1584
1585 WARN_ON_ONCE(nents > HV_MEMORY_HINT_MAX_GPA_PAGE_RANGES);
1586 WARN_ON_ONCE(sgl->length < HV_MIN_PAGE_REPORTING_LEN);
1587 local_irq_save(flags);
1588 hint = *(struct hv_memory_hint **)this_cpu_ptr(hyperv_pcpu_input_arg);
1589 if (!hint) {
1590 local_irq_restore(flags);
1591 return -ENOSPC;
1592 }
1593
1594 hint->type = HV_EXT_MEMORY_HEAT_HINT_TYPE_COLD_DISCARD;
1595 hint->reserved = 0;
1596 for_each_sg(sgl, sg, nents, i) {
1597 union hv_gpa_page_range *range;
1598
1599 range = &hint->ranges[i];
1600 range->address_space = 0;
1601
1602 range->page.largepage = 1;
1603 range->page.additional_pages =
1604 (sg->length / HV_MIN_PAGE_REPORTING_LEN) - 1;
1605 range->page_size = HV_GPA_PAGE_RANGE_PAGE_SIZE_2MB;
1606 range->base_large_pfn =
1607 page_to_hvpfn(sg_page(sg)) >> HV_MIN_PAGE_REPORTING_ORDER;
1608 }
1609
1610 status = hv_do_rep_hypercall(HV_EXT_CALL_MEMORY_HEAT_HINT, nents, 0,
1611 hint, NULL);
1612 local_irq_restore(flags);
1613 if ((status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS) {
1614 pr_err("Cold memory discard hypercall failed with status %llx\n",
1615 status);
1616 return -EINVAL;
1617 }
1618
1619 return 0;
1620}
1621
1622static void enable_page_reporting(void)
1623{
1624 int ret;
1625
1626
1627 if (pageblock_order < HV_MIN_PAGE_REPORTING_ORDER) {
1628 pr_debug("Cold memory discard is only supported on 2MB pages and above\n");
1629 return;
1630 }
1631
1632 if (!hv_query_ext_cap(HV_EXT_CAPABILITY_MEMORY_COLD_DISCARD_HINT)) {
1633 pr_debug("Cold memory discard hint not supported by Hyper-V\n");
1634 return;
1635 }
1636
1637 BUILD_BUG_ON(PAGE_REPORTING_CAPACITY > HV_MEMORY_HINT_MAX_GPA_PAGE_RANGES);
1638 dm_device.pr_dev_info.report = hv_free_page_report;
1639 ret = page_reporting_register(&dm_device.pr_dev_info);
1640 if (ret < 0) {
1641 dm_device.pr_dev_info.report = NULL;
1642 pr_err("Failed to enable cold memory discard: %d\n", ret);
1643 } else {
1644 pr_info("Cold memory discard hint enabled\n");
1645 }
1646}
1647
1648static void disable_page_reporting(void)
1649{
1650 if (dm_device.pr_dev_info.report) {
1651 page_reporting_unregister(&dm_device.pr_dev_info);
1652 dm_device.pr_dev_info.report = NULL;
1653 }
1654}
1655
1656static int balloon_connect_vsp(struct hv_device *dev)
1657{
1658 struct dm_version_request version_req;
1659 struct dm_capabilities cap_msg;
1660 unsigned long t;
1661 int ret;
1662
1663 ret = vmbus_open(dev->channel, dm_ring_size, dm_ring_size, NULL, 0,
1664 balloon_onchannelcallback, dev);
1665 if (ret)
1666 return ret;
1667
1668
1669
1670
1671
1672
1673
1674 memset(&version_req, 0, sizeof(struct dm_version_request));
1675 version_req.hdr.type = DM_VERSION_REQUEST;
1676 version_req.hdr.size = sizeof(struct dm_version_request);
1677 version_req.hdr.trans_id = atomic_inc_return(&trans_id);
1678 version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN10;
1679 version_req.is_last_attempt = 0;
1680 dm_device.version = version_req.version.version;
1681
1682 ret = vmbus_sendpacket(dev->channel, &version_req,
1683 sizeof(struct dm_version_request),
1684 (unsigned long)NULL, VM_PKT_DATA_INBAND, 0);
1685 if (ret)
1686 goto out;
1687
1688 t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
1689 if (t == 0) {
1690 ret = -ETIMEDOUT;
1691 goto out;
1692 }
1693
1694
1695
1696
1697
1698 if (dm_device.state == DM_INIT_ERROR) {
1699 ret = -EPROTO;
1700 goto out;
1701 }
1702
1703 pr_info("Using Dynamic Memory protocol version %u.%u\n",
1704 DYNMEM_MAJOR_VERSION(dm_device.version),
1705 DYNMEM_MINOR_VERSION(dm_device.version));
1706
1707
1708
1709
1710 memset(&cap_msg, 0, sizeof(struct dm_capabilities));
1711 cap_msg.hdr.type = DM_CAPABILITIES_REPORT;
1712 cap_msg.hdr.size = sizeof(struct dm_capabilities);
1713 cap_msg.hdr.trans_id = atomic_inc_return(&trans_id);
1714
1715
1716
1717
1718
1719
1720 cap_msg.caps.cap_bits.balloon = 1;
1721 cap_msg.caps.cap_bits.hot_add = 1;
1722
1723
1724
1725
1726
1727 cap_msg.caps.cap_bits.hot_add_alignment = 7;
1728
1729
1730
1731
1732
1733
1734 cap_msg.min_page_cnt = 0;
1735 cap_msg.max_page_number = -1;
1736
1737 ret = vmbus_sendpacket(dev->channel, &cap_msg,
1738 sizeof(struct dm_capabilities),
1739 (unsigned long)NULL, VM_PKT_DATA_INBAND, 0);
1740 if (ret)
1741 goto out;
1742
1743 t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
1744 if (t == 0) {
1745 ret = -ETIMEDOUT;
1746 goto out;
1747 }
1748
1749
1750
1751
1752
1753 if (dm_device.state == DM_INIT_ERROR) {
1754 ret = -EPROTO;
1755 goto out;
1756 }
1757
1758 return 0;
1759out:
1760 vmbus_close(dev->channel);
1761 return ret;
1762}
1763
1764static int balloon_probe(struct hv_device *dev,
1765 const struct hv_vmbus_device_id *dev_id)
1766{
1767 int ret;
1768
1769 allow_hibernation = hv_is_hibernation_supported();
1770 if (allow_hibernation)
1771 hot_add = false;
1772
1773#ifdef CONFIG_MEMORY_HOTPLUG
1774 do_hot_add = hot_add;
1775#else
1776 do_hot_add = false;
1777#endif
1778 dm_device.dev = dev;
1779 dm_device.state = DM_INITIALIZING;
1780 dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN8;
1781 init_completion(&dm_device.host_event);
1782 init_completion(&dm_device.config_event);
1783 INIT_LIST_HEAD(&dm_device.ha_region_list);
1784 spin_lock_init(&dm_device.ha_lock);
1785 INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up);
1786 INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req);
1787 dm_device.host_specified_ha_region = false;
1788
1789#ifdef CONFIG_MEMORY_HOTPLUG
1790 set_online_page_callback(&hv_online_page);
1791 init_completion(&dm_device.ol_waitevent);
1792 register_memory_notifier(&hv_memory_nb);
1793#endif
1794
1795 hv_set_drvdata(dev, &dm_device);
1796
1797 ret = balloon_connect_vsp(dev);
1798 if (ret != 0)
1799 return ret;
1800
1801 enable_page_reporting();
1802 dm_device.state = DM_INITIALIZED;
1803
1804 dm_device.thread =
1805 kthread_run(dm_thread_func, &dm_device, "hv_balloon");
1806 if (IS_ERR(dm_device.thread)) {
1807 ret = PTR_ERR(dm_device.thread);
1808 goto probe_error;
1809 }
1810
1811 return 0;
1812
1813probe_error:
1814 dm_device.state = DM_INIT_ERROR;
1815 dm_device.thread = NULL;
1816 disable_page_reporting();
1817 vmbus_close(dev->channel);
1818#ifdef CONFIG_MEMORY_HOTPLUG
1819 unregister_memory_notifier(&hv_memory_nb);
1820 restore_online_page_callback(&hv_online_page);
1821#endif
1822 return ret;
1823}
1824
1825static int balloon_remove(struct hv_device *dev)
1826{
1827 struct hv_dynmem_device *dm = hv_get_drvdata(dev);
1828 struct hv_hotadd_state *has, *tmp;
1829 struct hv_hotadd_gap *gap, *tmp_gap;
1830 unsigned long flags;
1831
1832 if (dm->num_pages_ballooned != 0)
1833 pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned);
1834
1835 cancel_work_sync(&dm->balloon_wrk.wrk);
1836 cancel_work_sync(&dm->ha_wrk.wrk);
1837
1838 kthread_stop(dm->thread);
1839 disable_page_reporting();
1840 vmbus_close(dev->channel);
1841#ifdef CONFIG_MEMORY_HOTPLUG
1842 unregister_memory_notifier(&hv_memory_nb);
1843 restore_online_page_callback(&hv_online_page);
1844#endif
1845 spin_lock_irqsave(&dm_device.ha_lock, flags);
1846 list_for_each_entry_safe(has, tmp, &dm->ha_region_list, list) {
1847 list_for_each_entry_safe(gap, tmp_gap, &has->gap_list, list) {
1848 list_del(&gap->list);
1849 kfree(gap);
1850 }
1851 list_del(&has->list);
1852 kfree(has);
1853 }
1854 spin_unlock_irqrestore(&dm_device.ha_lock, flags);
1855
1856 return 0;
1857}
1858
1859static int balloon_suspend(struct hv_device *hv_dev)
1860{
1861 struct hv_dynmem_device *dm = hv_get_drvdata(hv_dev);
1862
1863 tasklet_disable(&hv_dev->channel->callback_event);
1864
1865 cancel_work_sync(&dm->balloon_wrk.wrk);
1866 cancel_work_sync(&dm->ha_wrk.wrk);
1867
1868 if (dm->thread) {
1869 kthread_stop(dm->thread);
1870 dm->thread = NULL;
1871 vmbus_close(hv_dev->channel);
1872 }
1873
1874 tasklet_enable(&hv_dev->channel->callback_event);
1875
1876 return 0;
1877
1878}
1879
1880static int balloon_resume(struct hv_device *dev)
1881{
1882 int ret;
1883
1884 dm_device.state = DM_INITIALIZING;
1885
1886 ret = balloon_connect_vsp(dev);
1887
1888 if (ret != 0)
1889 goto out;
1890
1891 dm_device.thread =
1892 kthread_run(dm_thread_func, &dm_device, "hv_balloon");
1893 if (IS_ERR(dm_device.thread)) {
1894 ret = PTR_ERR(dm_device.thread);
1895 dm_device.thread = NULL;
1896 goto close_channel;
1897 }
1898
1899 dm_device.state = DM_INITIALIZED;
1900 return 0;
1901close_channel:
1902 vmbus_close(dev->channel);
1903out:
1904 dm_device.state = DM_INIT_ERROR;
1905#ifdef CONFIG_MEMORY_HOTPLUG
1906 unregister_memory_notifier(&hv_memory_nb);
1907 restore_online_page_callback(&hv_online_page);
1908#endif
1909 return ret;
1910}
1911
1912static const struct hv_vmbus_device_id id_table[] = {
1913
1914
1915 { HV_DM_GUID, },
1916 { },
1917};
1918
1919MODULE_DEVICE_TABLE(vmbus, id_table);
1920
1921static struct hv_driver balloon_drv = {
1922 .name = "hv_balloon",
1923 .id_table = id_table,
1924 .probe = balloon_probe,
1925 .remove = balloon_remove,
1926 .suspend = balloon_suspend,
1927 .resume = balloon_resume,
1928 .driver = {
1929 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1930 },
1931};
1932
1933static int __init init_balloon_drv(void)
1934{
1935
1936 return vmbus_driver_register(&balloon_drv);
1937}
1938
1939module_init(init_balloon_drv);
1940
1941MODULE_DESCRIPTION("Hyper-V Balloon");
1942MODULE_LICENSE("GPL");
1943