summaryrefslogtreecommitdiffstats
path: root/fs/nilfs2/ioctl.c
blob: 422fb54b73771f04690e16726f9a85a74c4febfd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
/*
 * ioctl.c - NILFS ioctl operations.
 *
 * Copyright (C) 2007, 2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Koji Sato <koji@osrg.net>.
 */

#include <linux/fs.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/capability.h>	/* capable() */
#include <linux/uaccess.h>	/* copy_from_user(), copy_to_user() */
#include <linux/vmalloc.h>
#include <linux/compat.h>	/* compat_ptr() */
#include <linux/mount.h>	/* mnt_want_write_file(), mnt_drop_write_file() */
#include <linux/buffer_head.h>
#include <linux/nilfs2_fs.h>
#include "nilfs.h"
#include "segment.h"
#include "bmap.h"
#include "cpfile.h"
#include "sufile.h"
#include "dat.h"

/**
 * nilfs_ioctl_wrap_copy - wrapping function of get/set metadata info
 * @nilfs: nilfs object
 * @argv: vector of arguments from userspace
 * @dir: set of direction flags
 * @dofunc: concrete function of get/set metadata info
 *
 * Description: nilfs_ioctl_wrap_copy() gets/sets metadata info by means of
 * calling dofunc() function on the basis of @argv argument.
 *
 * Return Value: On success, 0 is returned and requested metadata info
 * is copied into userspace. On error, one of the following
 * negative error codes is returned.
 *
 * %-EINVAL - Invalid arguments from userspace.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EFAULT - Failure during execution of requested operation.
 */
static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
				 struct nilfs_argv *argv, int dir,
				 ssize_t (*dofunc)(struct the_nilfs *,
						   __u64 *, int,
						   void *, size_t, size_t))
{
	void *buf;
	void __user *base = (void __user *)(unsigned long)argv->v_base;
	size_t maxmembs, total, n;
	ssize_t nr;
	int ret, i;
	__u64 pos, ppos;

	if (argv->v_nmembs == 0)
		return 0;

	if (argv->v_size > PAGE_SIZE)
		return -EINVAL;

	/*
	 * Reject pairs of a start item position (argv->v_index) and a
	 * total count (argv->v_nmembs) which leads position 'pos' to
	 * overflow by the increment at the end of the loop.
	 */
	if (argv->v_index > ~(__u64)0 - argv->v_nmembs)
		return -EINVAL;

	buf = (void *)__get_free_pages(GFP_NOFS, 0);
	if (unlikely(!buf))
		return -ENOMEM;
	maxmembs = PAGE_SIZE / argv->v_size;

	ret = 0;
	total = 0;
	pos = argv->v_index;
	for (i = 0; i < argv->v_nmembs; i += n) {
		n = (argv->v_nmembs - i < maxmembs) ?
			argv->v_nmembs - i : maxmembs;
		if ((dir & _IOC_WRITE) &&
		    copy_from_user(buf, base + argv->v_size * i,
				   argv->v_size * n)) {
			ret = -EFAULT;
			break;
		}
		ppos = pos;
		nr = dofunc(nilfs, &pos, argv->v_flags, buf, argv->v_size,
			       n);
		if (nr < 0) {
			ret = nr;
			break;
		}
		if ((dir & _IOC_READ) &&
		    copy_to_user(base + argv->v_size * i, buf,
				 argv->v_size * nr)) {
			ret = -EFAULT;
			break;
		}
		total += nr;
		if ((size_t)nr < n)
			break;
		if (pos == ppos)
			pos += n;
	}
	argv->v_nmembs = total;

	free_pages((unsigned long)buf, 0);
	return ret;
}

/**
 * nilfs_ioctl_getflags - ioctl to support lsattr
 */
static int nilfs_ioctl_getflags(struct inode *inode, void __user *argp)
{
	unsigned int flags = NILFS_I(inode)->i_flags & FS_FL_USER_VISIBLE;

	return put_user(flags, (int __user *)argp);
}

/**
 * nilfs_ioctl_setflags - ioctl to support chattr
 */
static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
				void __user *argp)
{
	struct nilfs_transaction_info ti;
	unsigned int flags, oldflags;
	int ret;

	if (!inode_owner_or_capable(inode))
		return -EACCES;

	if (get_user(flags, (int __user *)argp))
		return -EFAULT;

	ret = mnt_want_write_file(filp);
	if (ret)
		return ret;

	flags = nilfs_mask_flags(inode->i_mode, flags);

	mutex_lock(&inode->i_mutex);

	oldflags = NILFS_I(inode)->i_flags;

	/*
	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by the
	 * relevant capability.
	 */
	ret = -EPERM;
	if (((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) &&
	    !capable(CAP_LINUX_IMMUTABLE))
		goto out;

	ret = nilfs_transaction_begin(inode->i_sb, &ti, 0);
	if (ret)
		goto out;

	NILFS_I(inode)->i_flags = (oldflags & ~FS_FL_USER_MODIFIABLE) |
		(flags & FS_FL_USER_MODIFIABLE);

	nilfs_set_inode_flags(inode);
	inode->i_ctime = CURRENT_TIME;
	if (IS_SYNC(inode))
		nilfs_set_transaction_flag(NILFS_TI_SYNC);

	nilfs_mark_inode_dirty(inode);
	ret = nilfs_transaction_commit(inode->i_sb);
out:
	mutex_unlock(&inode->i_mutex);
	mnt_drop_write_file(filp);
	return ret;
}

/**
 * nilfs_ioctl_getversion - get info about a file's version (generation number)
 */
static int nilfs_ioctl_getversion(struct inode *inode, void __user *argp)
{
	return put_user(inode->i_generation, (int __user *)argp);
}

/**
 * nilfs_ioctl_change_cpmode - change checkpoint mode (checkpoint/snapshot)
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_change_cpmode() function changes mode of
 * given checkpoint between checkpoint and snapshot state. This ioctl
 * is used in chcp and mkcp utilities.
 *
 * Return Value: On success, 0 is returned and mode of a checkpoint is
 * changed. On error, one of the following negative error codes
 * is returned.
 *
 * %-EPERM - Operation not permitted.
 *
 * %-EFAULT - Failure during checkpoint mode changing.
 */
static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
				     unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_transaction_info ti;
	struct nilfs_cpmode cpmode;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(filp);
	if (ret)
		return ret;

	ret = -EFAULT;
	if (copy_from_user(&cpmode, argp, sizeof(cpmode)))
		goto out;

	mutex_lock(&nilfs->ns_snapshot_mount_mutex);

	nilfs_transaction_begin(inode->i_sb, &ti, 0);
	ret = nilfs_cpfile_change_cpmode(
		nilfs->ns_cpfile, cpmode.cm_cno, cpmode.cm_mode);
	if (unlikely(ret < 0))
		nilfs_transaction_abort(inode->i_sb);
	else
		nilfs_transaction_commit(inode->i_sb); /* never fails */

	mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
out:
	mnt_drop_write_file(filp);
	return ret;
}

/**
 * nilfs_ioctl_delete_checkpoint - remove checkpoint
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_delete_checkpoint() function removes
 * checkpoint from NILFS2 file system. This ioctl is used in rmcp
 * utility.
 *
 * Return Value: On success, 0 is returned and a checkpoint is
 * removed. On error, one of the following negative error codes
 * is returned.
 *
 * %-EPERM - Operation not permitted.
 *
 * %-EFAULT - Failure during checkpoint removing.
 */
static int
nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
			      unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_transaction_info ti;
	__u64 cno;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(filp);
	if (ret)
		return ret;

	ret = -EFAULT;
	if (copy_from_user(&cno, argp, sizeof(cno)))
		goto out;

	nilfs_transaction_begin(inode->i_sb, &ti, 0);
	ret = nilfs_cpfile_delete_checkpoint(nilfs->ns_cpfile, cno);
	if (unlikely(ret < 0))
		nilfs_transaction_abort(inode->i_sb);
	else
		nilfs_transaction_commit(inode->i_sb); /* never fails */
out:
	mnt_drop_write_file(filp);
	return ret;
}

/**
 * nilfs_ioctl_do_get_cpinfo - callback method getting info about checkpoints
 * @nilfs: nilfs object
 * @posp: pointer on array of checkpoint's numbers
 * @flags: checkpoint mode (checkpoint or snapshot)
 * @buf: buffer for storing checkponts' info
 * @size: size in bytes of one checkpoint info item in array
 * @nmembs: number of checkpoints in array (numbers and infos)
 *
 * Description: nilfs_ioctl_do_get_cpinfo() function returns info about
 * requested checkpoints. The NILFS_IOCTL_GET_CPINFO ioctl is used in
 * lscp utility and by nilfs_cleanerd daemon.
 *
 * Return value: count of nilfs_cpinfo structures in output buffer.
 */
static ssize_t
nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
			  void *buf, size_t size, size_t nmembs)
{
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
				      size, nmembs);
	up_read(&nilfs->ns_segctor_sem);
	return ret;
}

/**
 * nilfs_ioctl_get_cpstat - get checkpoints statistics
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_get_cpstat() returns information about checkpoints.
 * The NILFS_IOCTL_GET_CPSTAT ioctl is used by lscp, rmcp utilities
 * and by nilfs_cleanerd daemon.
 *
 * Return Value: On success, 0 is returned, and checkpoints information is
 * copied into userspace pointer @argp. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EFAULT - Failure during getting checkpoints statistics.
 */
static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
				  unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_cpstat cpstat;
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
	up_read(&nilfs->ns_segctor_sem);
	if (ret < 0)
		return ret;

	if (copy_to_user(argp, &cpstat, sizeof(cpstat)))
		ret = -EFAULT;
	return ret;
}

/**
 * nilfs_ioctl_do_get_suinfo - callback method getting segment usage info
 * @nilfs: nilfs object
 * @posp: pointer on array of segment numbers
 * @flags: *not used*
 * @buf: buffer for storing suinfo array
 * @size: size in bytes of one suinfo item in array
 * @nmembs: count of segment numbers and suinfos in array
 *
 * Description: nilfs_ioctl_do_get_suinfo() function returns segment usage
 * info about requested segments. The NILFS_IOCTL_GET_SUINFO ioctl is used
 * in lssu, nilfs_resize utilities and by nilfs_cleanerd daemon.
 *
 * Return value: count of nilfs_suinfo structures in output buffer.
 */
static ssize_t
nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
			  void *buf, size_t size, size_t nmembs)
{
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, size,
				      nmembs);
	up_read(&nilfs->ns_segctor_sem);
	return ret;
}

/**
 * nilfs_ioctl_get_sustat - get segment usage statistics
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_get_sustat() returns segment usage statistics.
 * The NILFS_IOCTL_GET_SUSTAT ioctl is used in lssu, nilfs_resize utilities
 * and by nilfs_cleanerd daemon.
 *
 * Return Value: On success, 0 is returned, and segment usage information is
 * copied into userspace pointer @argp. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EFAULT - Failure during getting segment usage statistics.
 */
static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
				  unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_sustat sustat;
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
	up_read(&nilfs->ns_segctor_sem);
	if (ret < 0)
		return ret;

	if (copy_to_user(argp, &sustat, sizeof(sustat)))
		ret = -EFAULT;
	return ret;
}

/**
 * nilfs_ioctl_do_get_vinfo - callback method getting virtual blocks info
 * @nilfs: nilfs object
 * @posp: *not used*
 * @flags: *not used*
 * @buf: buffer for storing array of nilfs_vinfo structures
 * @size: size in bytes of one vinfo item in array
 * @nmembs: count of vinfos in array
 *
 * Description: nilfs_ioctl_do_get_vinfo() function returns information
 * on virtual block addresses. The NILFS_IOCTL_GET_VINFO ioctl is used
 * by nilfs_cleanerd daemon.
 *
 * Return value: count of nilfs_vinfo structures in output buffer.
 */
static ssize_t
nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
			 void *buf, size_t size, size_t nmembs)
{
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_dat_get_vinfo(nilfs->ns_dat, buf, size, nmembs);
	up_read(&nilfs->ns_segctor_sem);
	return ret;
}

/**
 * nilfs_ioctl_do_get_bdescs - callback method getting disk block descriptors
 * @nilfs: nilfs object
 * @posp: *not used*
 * @flags: *not used*
 * @buf: buffer for storing array of nilfs_bdesc structures
 * @size: size in bytes of one bdesc item in array
 * @nmembs: count of bdescs in array
 *
 * Description: nilfs_ioctl_do_get_bdescs() function returns information
 * about descriptors of disk block numbers. The NILFS_IOCTL_GET_BDESCS ioctl
 * is used by nilfs_cleanerd daemon.
 *
 * Return value: count of nilfs_bdescs structures in output buffer.
 */
static ssize_t
nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
			  void *buf, size_t size, size_t nmembs)
{
	struct nilfs_bmap *bmap = NILFS_I(nilfs->ns_dat)->i_bmap;
	struct nilfs_bdesc *bdescs = buf;
	int ret, i;

	down_read(&nilfs->ns_segctor_sem);
	for (i = 0; i < nmembs; i++) {
		ret = nilfs_bmap_lookup_at_level(bmap,
						 bdescs[i].bd_offset,
						 bdescs[i].bd_level + 1,
						 &bdescs[i].bd_blocknr);
		if (ret < 0) {
			if (ret != -ENOENT) {
				up_read(&nilfs->ns_segctor_sem);
				return ret;
			}
			bdescs[i].bd_blocknr = 0;
		}
	}
	up_read(&nilfs->ns_segctor_sem);
	return nmembs;
}

/**
 * nilfs_ioctl_get_bdescs - get disk block descriptors
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_do_get_bdescs() function returns information
 * about descriptors of disk block numbers. The NILFS_IOCTL_GET_BDESCS ioctl
 * is used by nilfs_cleanerd daemon.
 *
 * Return Value: On success, 0 is returned, and disk block descriptors are
 * copied into userspace pointer @argp. On error, one of the following
 * negative error codes is returned.
 *
 * %-EINVAL - Invalid arguments from userspace.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EFAULT - Failure during getting disk block descriptors.
 */
static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
				  unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_argv argv;
	int ret;

	if (copy_from_user(&argv, argp, sizeof(argv)))
		return -EFAULT;

	if (argv.v_size != sizeof(struct nilfs_bdesc))
		return -EINVAL;

	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
				    nilfs_ioctl_do_get_bdescs);
	if (ret < 0)
		return ret;

	if (copy_to_user(argp, &argv, sizeof(argv)))
		ret = -EFAULT;
	return ret;
}

/**
 * nilfs_ioctl_move_inode_block - prepare data/node block for moving by GC
 * @inode: inode object
 * @vdesc: descriptor of virtual block number
 * @buffers: list of moving buffers
 *
 * Description: nilfs_ioctl_move_inode_block() function registers data/node
 * buffer in the GC pagecache and submit read request.
 *
 * Return Value: On success, 0 is returned. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-ENOENT - Requested block doesn't exist.
 *
 * %-EEXIST - Blocks conflict is detected.
 */
static int nilfs_ioctl_move_inode_block(struct inode *inode,
					struct nilfs_vdesc *vdesc,
					struct list_head *buffers)
{
	struct buffer_head *bh;
	int ret;

	if (vdesc->vd_flags == 0)
		ret = nilfs_gccache_submit_read_data(
			inode, vdesc->vd_offset, vdesc->vd_blocknr,
			vdesc->vd_vblocknr, &bh);
	else
		ret = nilfs_gccache_submit_read_node(
			inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);

	if (unlikely(ret < 0)) {
		if (ret == -ENOENT)
			printk(KERN_CRIT
			       "%s: invalid virtual block address (%s): "
			       "ino=%llu, cno=%llu, offset=%llu, "
			       "blocknr=%llu, vblocknr=%llu\n",
			       __func__, vdesc->vd_flags ? "node" : "data",
			       (unsigned long long)vdesc->vd_ino,
			       (unsigned long long)vdesc->vd_cno,
			       (unsigned long long)vdesc->vd_offset,
			       (unsigned long long)vdesc->vd_blocknr,
			       (unsigned long long)vdesc->vd_vblocknr);
		return ret;
	}
	if (unlikely(!list_empty(&bh->b_assoc_buffers))) {
		printk(KERN_CRIT "%s: conflicting %s buffer: ino=%llu, "
		       "cno=%llu, offset=%llu, blocknr=%llu, vblocknr=%llu\n",
		       __func__, vdesc->vd_flags ? "node" : "data",
		       (unsigned long long)vdesc->vd_ino,
		       (unsigned long long)vdesc->vd_cno,
		       (unsigned long long)vdesc->vd_offset,
		       (unsigned long long)vdesc->vd_blocknr,
		       (unsigned long long)vdesc->vd_vblocknr);
		brelse(bh);
		return -EEXIST;
	}
	list_add_tail(&bh->b_assoc_buffers, buffers);
	return 0;
}

/**
 * nilfs_ioctl_move_blocks - move valid inode's blocks during garbage collection
 * @sb: superblock object
 * @argv: vector of arguments from userspace
 * @buf: array of nilfs_vdesc structures
 *
 * Description: nilfs_ioctl_move_blocks() function reads valid data/node
 * blocks that garbage collector specified with the array of nilfs_vdesc
 * structures and stores them into page caches of GC inodes.
 *
 * Return Value: Number of processed nilfs_vdesc structures or
 * error code, otherwise.
 */
static int nilfs_ioctl_move_blocks(struct super_block *sb,
				   struct nilfs_argv *argv, void *buf)
{
	size_t nmembs = argv->v_nmembs;
	struct the_nilfs *nilfs = sb->s_fs_info;
	struct inode *inode;
	struct nilfs_vdesc *vdesc;
	struct buffer_head *bh, *n;
	LIST_HEAD(buffers);
	ino_t ino;
	__u64 cno;
	int i, ret;

	for (i = 0, vdesc = buf; i < nmembs; ) {
		ino = vdesc->vd_ino;
		cno = vdesc->vd_cno;
		inode = nilfs_iget_for_gc(sb, ino, cno);
		if (IS_ERR(inode)) {
			ret = PTR_ERR(inode);
			goto failed;
		}
		if (list_empty(&NILFS_I(inode)->i_dirty)) {
			/*
			 * Add the inode to GC inode list. Garbage Collection
			 * is serialized and no two processes manipulate the
			 * list simultaneously.
			 */
			igrab(inode);
			list_add(&NILFS_I(inode)->i_dirty,
				 &nilfs->ns_gc_inodes);
		}

		do {
			ret = nilfs_ioctl_move_inode_block(inode, vdesc,
							   &buffers);
			if (unlikely(ret < 0)) {
				iput(inode);
				goto failed;
			}
			vdesc++;
		} while (++i < nmembs &&
			 vdesc->vd_ino == ino && vdesc->vd_cno == cno);

		iput(inode); /* The inode still remains in GC inode list */
	}

	list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
		ret = nilfs_gccache_wait_and_mark_dirty(bh);
		if (unlikely(ret < 0)) {
			WARN_ON(ret == -EEXIST);
			goto failed;
		}
		list_del_init(&bh->b_assoc_buffers);
		brelse(bh);
	}
	return nmembs;

 failed:
	list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
		list_del_init(&bh->b_assoc_buffers);
		brelse(bh);
	}
	return ret;
}

/**
 * nilfs_ioctl_delete_checkpoints - delete checkpoints
 * @nilfs: nilfs object
 * @argv: vector of arguments from userspace
 * @buf: array of periods of checkpoints numbers
 *
 * Description: nilfs_ioctl_delete_checkpoints() function deletes checkpoints
 * in the period from p_start to p_end, excluding p_end itself. The checkpoints
 * which have been already deleted are ignored.
 *
 * Return Value: Number of processed nilfs_period structures or
 * error code, otherwise.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EINVAL - invalid checkpoints.
 */
static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
					  struct nilfs_argv *argv, void *buf)
{
	size_t nmembs = argv->v_nmembs;
	struct inode *cpfile = nilfs->ns_cpfile;
	struct nilfs_period *periods = buf;
	int ret, i;

	for (i = 0; i < nmembs; i++) {
		ret = nilfs_cpfile_delete_checkpoints(
			cpfile, periods[i].p_start, periods[i].p_end);
		if (ret < 0)
			return ret;
	}
	return nmembs;
}

/**
 * nilfs_ioctl_free_vblocknrs - free virtual block numbers
 * @nilfs: nilfs object
 * @argv: vector of arguments from userspace
 * @buf: array of virtual block numbers
 *
 * Description: nilfs_ioctl_free_vblocknrs() function frees
 * the virtual block numbers specified by @buf and @argv->v_nmembs.
 *
 * Return Value: Number of processed virtual block numbers or
 * error code, otherwise.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-ENOENT - The virtual block number have not been allocated.
 */
static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
				      struct nilfs_argv *argv, void *buf)
{
	size_t nmembs = argv->v_nmembs;
	int ret;

	ret = nilfs_dat_freev(nilfs->ns_dat, buf, nmembs);

	return (ret < 0) ? ret : nmembs;
}

/**
 * nilfs_ioctl_mark_blocks_dirty - mark blocks dirty
 * @nilfs: nilfs object
 * @argv: vector of arguments from userspace
 * @buf: array of block descriptors
 *
 * Description: nilfs_ioctl_mark_blocks_dirty() function marks
 * metadata file or data blocks as dirty.
 *
 * Return Value: Number of processed block descriptors or
 * error code, otherwise.
 *
 * %-ENOMEM - Insufficient memory available.
 *
 * %-EIO - I/O error
 *
 * %-ENOENT - the specified block does not exist (hole block)
 */
static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
					 struct nilfs_argv *argv, void *buf)
{
	size_t nmembs = argv->v_nmembs;
	struct nilfs_bmap *bmap = NILFS_I(nilfs->ns_dat)->i_bmap;
	struct nilfs_bdesc *bdescs = buf;
	int ret, i;

	for (i = 0; i < nmembs; i++) {
		/* XXX: use macro or inline func to check liveness */
		ret = nilfs_bmap_lookup_at_level(bmap,
						 bdescs[i].bd_offset,
						 bdescs[i].bd_level + 1,
						 &bdescs[i].bd_blocknr);
		if (ret < 0) {
			if (ret != -ENOENT)
				return ret;
			bdescs[i].bd_blocknr = 0;
		}
		if (bdescs[i].bd_blocknr != bdescs[i].bd_oblocknr)
			/* skip dead block */
			continue;
		if (bdescs[i].bd_level == 0) {
			ret = nilfs_mdt_mark_block_dirty(nilfs->ns_dat,
							 bdescs[i].bd_offset);
			if (ret < 0) {
				WARN_ON(ret == -ENOENT);
				return ret;
			}
		} else {
			ret = nilfs_bmap_mark(bmap, bdescs[i].bd_offset,
					      bdescs[i].bd_level);
			if (ret < 0) {
				WARN_ON(ret == -ENOENT);
				return ret;
			}
		}
	}
	return nmembs;
}

int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
				       struct nilfs_argv *argv, void **kbufs)
{
	const char *msg;
	int ret;

	ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], kbufs[1]);
	if (ret < 0) {
		/*
		 * can safely abort because checkpoints can be removed
		 * independently.
		 */
		msg = "cannot delete checkpoints";
		goto failed;
	}
	ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], kbufs[2]);
	if (ret < 0) {
		/*
		 * can safely abort because DAT file is updated atomically
		 * using a copy-on-write technique.
		 */
		msg = "cannot delete virtual blocks from DAT file";
		goto failed;
	}
	ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], kbufs[3]);
	if (ret < 0) {
		/*
		 * can safely abort because the operation is nondestructive.
		 */
		msg = "cannot mark copying blocks dirty";
		goto failed;
	}
	return 0;

 failed:
	printk(KERN_ERR "NILFS: GC failed during preparation: %s: err=%d\n",
	       msg, ret);
	return ret;
}

/**
 * nilfs_ioctl_clean_segments - clean segments
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_clean_segments() function makes garbage
 * collection operation in the environment of requested parameters
 * from userspace. The NILFS_IOCTL_CLEAN_SEGMENTS ioctl is used by
 * nilfs_cleanerd daemon.
 *
 * Return Value: On success, 0 is returned or error code, otherwise.
 */
static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
				      unsigned int cmd, void __user *argp)
{
	struct nilfs_argv argv[5];
	static const size_t argsz[5] = {
		sizeof(struct nilfs_vdesc),
		sizeof(struct nilfs_period),
		sizeof(__u64),
		sizeof(struct nilfs_bdesc),
		sizeof(__u64),
	};
	void __user *base;
	void *kbufs[5];
	struct the_nilfs *nilfs;
	size_t len, nsegs;
	int n, ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(filp);
	if (ret)
		return ret;

	ret = -EFAULT;
	if (copy_from_user(argv, argp, sizeof(argv)))
		goto out;

	ret = -EINVAL;
	nsegs = argv[4].v_nmembs;
	if (argv[4].v_size != argsz[4])
		goto out;
	if (nsegs > UINT_MAX / sizeof(__u64))
		goto out;

	/*
	 * argv[4] points to segment numbers this ioctl cleans.  We
	 * use kmalloc() for its buffer because memory used for the
	 * segment numbers is enough small.
	 */
	kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base,
			       nsegs * sizeof(__u64));
	if (IS_ERR(kbufs[4])) {
		ret = PTR_ERR(kbufs[4]);
		goto out;
	}
	nilfs = inode->i_sb->s_fs_info;

	for (n = 0; n < 4; n++) {
		ret = -EINVAL;
		if (argv[n].v_size != argsz[n])
			goto out_free;

		if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
			goto out_free;

		if (argv[n].v_nmembs >= UINT_MAX / argv[n].v_size)
			goto out_free;

		len = argv[n].v_size * argv[n].v_nmembs;
		base = (void __user *)(unsigned long)argv[n].v_base;
		if (len == 0) {
			kbufs[n] = NULL;
			continue;
		}

		kbufs[n] = vmalloc(len);
		if (!kbufs[n]) {
			ret = -ENOMEM;
			goto out_free;
		}
		if (copy_from_user(kbufs[n], base, len)) {
			ret = -EFAULT;
			vfree(kbufs[n]);
			goto out_free;
		}
	}

	/*
	 * nilfs_ioctl_move_blocks() will call nilfs_iget_for_gc(),
	 * which will operates an inode list without blocking.
	 * To protect the list from concurrent operations,
	 * nilfs_ioctl_move_blocks should be atomic operation.
	 */
	if (test_and_set_bit(THE_NILFS_GC_RUNNING, &nilfs->ns_flags)) {
		ret = -EBUSY;
		goto out_free;
	}

	ret = nilfs_ioctl_move_blocks(inode->i_sb, &argv[0], kbufs[0]);
	if (ret < 0)
		printk(KERN_ERR "NILFS: GC failed during preparation: "
			"cannot read source blocks: err=%d\n", ret);
	else {
		if (nilfs_sb_need_update(nilfs))
			set_nilfs_discontinued(nilfs);
		ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);
	}

	nilfs_remove_all_gcinodes(nilfs);
	clear_nilfs_gc_running(nilfs);

out_free:
	while (--n >= 0)
		vfree(kbufs[n]);
	kfree(kbufs[4]);
out:
	mnt_drop_write_file(filp);
	return ret;
}

/**
 * nilfs_ioctl_sync - make a checkpoint
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: nilfs_ioctl_sync() function constructs a logical segment
 * for checkpointing.  This function guarantees that all modified data
 * and metadata are written out to the device when it successfully
 * returned.
 *
 * Return Value: On success, 0 is retured. On errors, one of the following
 * negative error code is returned.
 *
 * %-EROFS - Read only filesystem.
 *
 * %-EIO - I/O error
 *
 * %-ENOSPC - No space left on device (only in a panic state).
 *
 * %-ERESTARTSYS - Interrupted.
 *
 * %-ENOMEM - Insufficient memory available.
 *
 * %-EFAULT - Failure during execution of requested operation.
 */
static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
			    unsigned int cmd, void __user *argp)
{
	__u64 cno;
	int ret;
	struct the_nilfs *nilfs;

	ret = nilfs_construct_segment(inode->i_sb);
	if (ret < 0)
		return ret;

	nilfs = inode->i_sb->s_fs_info;
	if (nilfs_test_opt(nilfs, BARRIER)) {
		ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
		if (ret == -EIO)
			return ret;
	}

	if (argp != NULL) {
		down_read(&nilfs->ns_segctor_sem);
		cno = nilfs->ns_cno - 1;
		up_read(&nilfs->ns_segctor_sem);
		if (copy_to_user(argp, &cno, sizeof(cno)))
			return -EFAULT;
	}
	return 0;
}

/**
 * nilfs_ioctl_resize - resize NILFS2 volume
 * @inode: inode object
 * @filp: file object
 * @argp: pointer on argument from userspace
 *
 * Return Value: On success, 0 is returned or error code, otherwise.
 */
static int nilfs_ioctl_resize(struct inode *inode, struct file *filp,
			      void __user *argp)
{
	__u64 newsize;
	int ret = -EPERM;

	if (!capable(CAP_SYS_ADMIN))
		goto out;

	ret = mnt_want_write_file(filp);
	if (ret)
		goto out;

	ret = -EFAULT;
	if (copy_from_user(&newsize, argp, sizeof(newsize)))
		goto out_drop_write;

	ret = nilfs_resize_fs(inode->i_sb, newsize);

out_drop_write:
	mnt_drop_write_file(filp);
out:
	return ret;
}

/**
 * nilfs_ioctl_trim_fs() - trim ioctl handle function
 * @inode: inode object
 * @argp: pointer on argument from userspace
 *
 * Decription: nilfs_ioctl_trim_fs is the FITRIM ioctl handle function. It
 * checks the arguments from userspace and calls nilfs_sufile_trim_fs, which
 * performs the actual trim operation.
 *
 * Return Value: On success, 0 is returned or negative error code, otherwise.
 */
static int nilfs_ioctl_trim_fs(struct inode *inode, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct request_queue *q = bdev_get_queue(nilfs->ns_bdev);
	struct fstrim_range range;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (!blk_queue_discard(q))
		return -EOPNOTSUPP;

	if (copy_from_user(&range, argp, sizeof(range)))
		return -EFAULT;

	range.minlen = max_t(u64, range.minlen, q->limits.discard_granularity);

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_sufile_trim_fs(nilfs->ns_sufile, &range);
	up_read(&nilfs->ns_segctor_sem);

	if (ret < 0)
		return ret;

	if (copy_to_user(argp, &range, sizeof(range)))
		return -EFAULT;

	return 0;
}

/**
 * nilfs_ioctl_set_alloc_range - limit range of segments to be allocated
 * @inode: inode object
 * @argp: pointer on argument from userspace
 *
 * Decription: nilfs_ioctl_set_alloc_range() function defines lower limit
 * of segments in bytes and upper limit of segments in bytes.
 * The NILFS_IOCTL_SET_ALLOC_RANGE is used by nilfs_resize utility.
 *
 * Return Value: On success, 0 is returned or error code, otherwise.
 */
static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	__u64 range[2];
	__u64 minseg, maxseg;
	unsigned long segbytes;
	int ret = -EPERM;

	if (!capable(CAP_SYS_ADMIN))
		goto out;

	ret = -EFAULT;
	if (copy_from_user(range, argp, sizeof(__u64[2])))
		goto out;

	ret = -ERANGE;
	if (range[1] > i_size_read(inode->i_sb->s_bdev->bd_inode))
		goto out;

	segbytes = nilfs->ns_blocks_per_segment * nilfs->ns_blocksize;

	minseg = range[0] + segbytes - 1;
	do_div(minseg, segbytes);
	maxseg = NILFS_SB2_OFFSET_BYTES(range[1]);
	do_div(maxseg, segbytes);
	maxseg--;

	ret = nilfs_sufile_set_alloc_range(nilfs->ns_sufile, minseg, maxseg);
out:
	return ret;
}

/**
 * nilfs_ioctl_get_info - wrapping function of get metadata info
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 * @membsz: size of an item in bytes
 * @dofunc: concrete function of getting metadata info
 *
 * Description: nilfs_ioctl_get_info() gets metadata info by means of
 * calling dofunc() function.
 *
 * Return Value: On success, 0 is returned and requested metadata info
 * is copied into userspace. On error, one of the following
 * negative error codes is returned.
 *
 * %-EINVAL - Invalid arguments from userspace.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EFAULT - Failure during execution of requested operation.
 */
static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
				unsigned int cmd, void __user *argp,
				size_t membsz,
				ssize_t (*dofunc)(struct the_nilfs *,
						  __u64 *, int,
						  void *, size_t, size_t))

{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_argv argv;
	int ret;

	if (copy_from_user(&argv, argp, sizeof(argv)))
		return -EFAULT;

	if (argv.v_size < membsz)
		return -EINVAL;

	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
	if (ret < 0)
		return ret;

	if (copy_to_user(argp, &argv, sizeof(argv)))
		ret = -EFAULT;
	return ret;
}

/**
 * nilfs_ioctl_set_suinfo - set segment usage info
 * @inode: inode object
 * @filp: file object
 * @cmd: ioctl's request code
 * @argp: pointer on argument from userspace
 *
 * Description: Expects an array of nilfs_suinfo_update structures
 * encapsulated in nilfs_argv and updates the segment usage info
 * according to the flags in nilfs_suinfo_update.
 *
 * Return Value: On success, 0 is returned. On error, one of the
 * following negative error codes is returned.
 *
 * %-EPERM - Not enough permissions
 *
 * %-EFAULT - Error copying input data
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
 */
static int nilfs_ioctl_set_suinfo(struct inode *inode, struct file *filp,
				unsigned int cmd, void __user *argp)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_transaction_info ti;
	struct nilfs_argv argv;
	size_t len;
	void __user *base;
	void *kbuf;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(filp);
	if (ret)
		return ret;

	ret = -EFAULT;
	if (copy_from_user(&argv, argp, sizeof(argv)))
		goto out;

	ret = -EINVAL;
	if (argv.v_size < sizeof(struct nilfs_suinfo_update))
		goto out;

	if (argv.v_nmembs > nilfs->ns_nsegments)
		goto out;

	if (argv.v_nmembs >= UINT_MAX / argv.v_size)
		goto out;

	len = argv.v_size * argv.v_nmembs;
	if (!len) {
		ret = 0;
		goto out;
	}

	base = (void __user *)(unsigned long)argv.v_base;
	kbuf = vmalloc(len);
	if (!kbuf) {
		ret = -ENOMEM;
		goto out;
	}

	if (copy_from_user(kbuf, base, len)) {
		ret = -EFAULT;
		goto out_free;
	}

	nilfs_transaction_begin(inode->i_sb, &ti, 0);
	ret = nilfs_sufile_set_suinfo(nilfs->ns_sufile, kbuf, argv.v_size,
			argv.v_nmembs);
	if (unlikely(ret < 0))
		nilfs_transaction_abort(inode->i_sb);
	else
		nilfs_transaction_commit(inode->i_sb); /* never fails */

out_free:
	vfree(kbuf);
out:
	mnt_drop_write_file(filp);
	return ret;
}

long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file_inode(filp);
	void __user *argp = (void __user *)arg;

	switch (cmd) {
	case FS_IOC_GETFLAGS:
		return nilfs_ioctl_getflags(inode, argp);
	case FS_IOC_SETFLAGS:
		return nilfs_ioctl_setflags(inode, filp, argp);
	case FS_IOC_GETVERSION:
		return nilfs_ioctl_getversion(inode, argp);
	case NILFS_IOCTL_CHANGE_CPMODE:
		return nilfs_ioctl_change_cpmode(inode, filp, cmd, argp);
	case NILFS_IOCTL_DELETE_CHECKPOINT:
		return nilfs_ioctl_delete_checkpoint(inode, filp, cmd, argp);
	case NILFS_IOCTL_GET_CPINFO:
		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
					    sizeof(struct nilfs_cpinfo),
					    nilfs_ioctl_do_get_cpinfo);
	case NILFS_IOCTL_GET_CPSTAT:
		return nilfs_ioctl_get_cpstat(inode, filp, cmd, argp);
	case NILFS_IOCTL_GET_SUINFO:
		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
					    sizeof(struct nilfs_suinfo),
					    nilfs_ioctl_do_get_suinfo);
	case NILFS_IOCTL_SET_SUINFO:
		return nilfs_ioctl_set_suinfo(inode, filp, cmd, argp);
	case NILFS_IOCTL_GET_SUSTAT:
		return nilfs_ioctl_get_sustat(inode, filp, cmd, argp);
	case NILFS_IOCTL_GET_VINFO:
		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
					    sizeof(struct nilfs_vinfo),
					    nilfs_ioctl_do_get_vinfo);
	case NILFS_IOCTL_GET_BDESCS:
		return nilfs_ioctl_get_bdescs(inode, filp, cmd, argp);
	case NILFS_IOCTL_CLEAN_SEGMENTS:
		return nilfs_ioctl_clean_segments(inode, filp, cmd, argp);
	case NILFS_IOCTL_SYNC:
		return nilfs_ioctl_sync(inode, filp, cmd, argp);
	case NILFS_IOCTL_RESIZE:
		return nilfs_ioctl_resize(inode, filp, argp);
	case NILFS_IOCTL_SET_ALLOC_RANGE:
		return nilfs_ioctl_set_alloc_range(inode, argp);
	case FITRIM:
		return nilfs_ioctl_trim_fs(inode, argp);
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long nilfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	switch (cmd) {
	case FS_IOC32_GETFLAGS:
		cmd = FS_IOC_GETFLAGS;
		break;
	case FS_IOC32_SETFLAGS:
		cmd = FS_IOC_SETFLAGS;
		break;
	case FS_IOC32_GETVERSION:
		cmd = FS_IOC_GETVERSION;
		break;
	case NILFS_IOCTL_CHANGE_CPMODE:
	case NILFS_IOCTL_DELETE_CHECKPOINT:
	case NILFS_IOCTL_GET_CPINFO:
	case NILFS_IOCTL_GET_CPSTAT:
	case NILFS_IOCTL_GET_SUINFO:
	case NILFS_IOCTL_SET_SUINFO:
	case NILFS_IOCTL_GET_SUSTAT:
	case NILFS_IOCTL_GET_VINFO:
	case NILFS_IOCTL_GET_BDESCS:
	case NILFS_IOCTL_CLEAN_SEGMENTS:
	case NILFS_IOCTL_SYNC:
	case NILFS_IOCTL_RESIZE:
	case NILFS_IOCTL_SET_ALLOC_RANGE:
	case FITRIM:
		break;
	default:
		return -ENOIOCTLCMD;
	}
	return nilfs_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#endif
OpenPOWER on IntegriCloud