aboutsummaryrefslogtreecommitdiffstats
path: root/fs/xfs/xfs_fsops.c
blob: 502483c41f972e14590a1bae527897ca2f49a64f (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
/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * 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.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_btree.h"
#include "xfs_error.h"
#include "xfs_alloc.h"
#include "xfs_ialloc.h"
#include "xfs_fsops.h"
#include "xfs_itable.h"
#include "xfs_trans_space.h"
#include "xfs_rtalloc.h"
#include "xfs_rw.h"

/*
 * File system operations
 */

int
xfs_fs_geometry(
	xfs_mount_t		*mp,
	xfs_fsop_geom_t		*geo,
	int			new_version)
{
	geo->blocksize = mp->m_sb.sb_blocksize;
	geo->rtextsize = mp->m_sb.sb_rextsize;
	geo->agblocks = mp->m_sb.sb_agblocks;
	geo->agcount = mp->m_sb.sb_agcount;
	geo->logblocks = mp->m_sb.sb_logblocks;
	geo->sectsize = mp->m_sb.sb_sectsize;
	geo->inodesize = mp->m_sb.sb_inodesize;
	geo->imaxpct = mp->m_sb.sb_imax_pct;
	geo->datablocks = mp->m_sb.sb_dblocks;
	geo->rtblocks = mp->m_sb.sb_rblocks;
	geo->rtextents = mp->m_sb.sb_rextents;
	geo->logstart = mp->m_sb.sb_logstart;
	ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
	memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
	if (new_version >= 2) {
		geo->sunit = mp->m_sb.sb_unit;
		geo->swidth = mp->m_sb.sb_width;
	}
	if (new_version >= 3) {
		geo->version = XFS_FSOP_GEOM_VERSION;
		geo->flags =
			(XFS_SB_VERSION_HASATTR(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
			(XFS_SB_VERSION_HASNLINK(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
			(XFS_SB_VERSION_HASQUOTA(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
			(XFS_SB_VERSION_HASALIGN(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
			(XFS_SB_VERSION_HASDALIGN(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
			(XFS_SB_VERSION_HASSHARED(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
			(XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
			(XFS_SB_VERSION_HASDIRV2(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
			(XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
			(XFS_SB_VERSION_HASATTR2(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_ATTR2 : 0);
		geo->logsectsize = XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
				mp->m_sb.sb_logsectsize : BBSIZE;
		geo->rtsectsize = mp->m_sb.sb_blocksize;
		geo->dirblocksize = mp->m_dirblksize;
	}
	if (new_version >= 4) {
		geo->flags |=
			(XFS_SB_VERSION_HASLOGV2(&mp->m_sb) ?
				XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
		geo->logsunit = mp->m_sb.sb_logsunit;
	}
	return 0;
}

static int
xfs_growfs_data_private(
	xfs_mount_t		*mp,		/* mount point for filesystem */
	xfs_growfs_data_t	*in)		/* growfs data input struct */
{
	xfs_agf_t		*agf;
	xfs_agi_t		*agi;
	xfs_agnumber_t		agno;
	xfs_extlen_t		agsize;
	xfs_extlen_t		tmpsize;
	xfs_alloc_rec_t		*arec;
	xfs_btree_sblock_t	*block;
	xfs_buf_t		*bp;
	int			bucket;
	int			dpct;
	int			error;
	xfs_agnumber_t		nagcount;
	xfs_agnumber_t		nagimax = 0;
	xfs_rfsblock_t		nb, nb_mod;
	xfs_rfsblock_t		new;
	xfs_rfsblock_t		nfree;
	xfs_agnumber_t		oagcount;
	int			pct;
	xfs_sb_t		*sbp;
	xfs_trans_t		*tp;

	nb = in->newblocks;
	pct = in->imaxpct;
	if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
		return XFS_ERROR(EINVAL);
	dpct = pct - mp->m_sb.sb_imax_pct;
	error = xfs_read_buf(mp, mp->m_ddev_targp,
			XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
			XFS_FSS_TO_BB(mp, 1), 0, &bp);
	if (error)
		return error;
	ASSERT(bp);
	xfs_buf_relse(bp);

	new = nb;	/* use new as a temporary here */
	nb_mod = do_div(new, mp->m_sb.sb_agblocks);
	nagcount = new + (nb_mod != 0);
	if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
		nagcount--;
		nb = nagcount * mp->m_sb.sb_agblocks;
		if (nb < mp->m_sb.sb_dblocks)
			return XFS_ERROR(EINVAL);
	}
	new = nb - mp->m_sb.sb_dblocks;
	oagcount = mp->m_sb.sb_agcount;
	if (nagcount > oagcount) {
		down_write(&mp->m_peraglock);
		mp->m_perag = kmem_realloc(mp->m_perag,
			sizeof(xfs_perag_t) * nagcount,
			sizeof(xfs_perag_t) * oagcount,
			KM_SLEEP);
		memset(&mp->m_perag[oagcount], 0,
			(nagcount - oagcount) * sizeof(xfs_perag_t));
		mp->m_flags |= XFS_MOUNT_32BITINODES;
		nagimax = xfs_initialize_perag(XFS_MTOVFS(mp), mp, nagcount);
		up_write(&mp->m_peraglock);
	}
	tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
	if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
			XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
		xfs_trans_cancel(tp, 0);
		return error;
	}

	nfree = 0;
	for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
		/*
		 * AG freelist header block
		 */
		bp = xfs_buf_get(mp->m_ddev_targp,
				  XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
				  XFS_FSS_TO_BB(mp, 1), 0);
		agf = XFS_BUF_TO_AGF(bp);
		memset(agf, 0, mp->m_sb.sb_sectsize);
		agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
		agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
		agf->agf_seqno = cpu_to_be32(agno);
		if (agno == nagcount - 1)
			agsize =
				nb -
				(agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
		else
			agsize = mp->m_sb.sb_agblocks;
		agf->agf_length = cpu_to_be32(agsize);
		agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
		agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
		agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
		agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
		agf->agf_flfirst = 0;
		agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
		agf->agf_flcount = 0;
		tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
		agf->agf_freeblks = cpu_to_be32(tmpsize);
		agf->agf_longest = cpu_to_be32(tmpsize);
		error = xfs_bwrite(mp, bp);
		if (error) {
			goto error0;
		}
		/*
		 * AG inode header block
		 */
		bp = xfs_buf_get(mp->m_ddev_targp,
				  XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
				  XFS_FSS_TO_BB(mp, 1), 0);
		agi = XFS_BUF_TO_AGI(bp);
		memset(agi, 0, mp->m_sb.sb_sectsize);
		agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
		agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
		agi->agi_seqno = cpu_to_be32(agno);
		agi->agi_length = cpu_to_be32(agsize);
		agi->agi_count = 0;
		agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
		agi->agi_level = cpu_to_be32(1);
		agi->agi_freecount = 0;
		agi->agi_newino = cpu_to_be32(NULLAGINO);
		agi->agi_dirino = cpu_to_be32(NULLAGINO);
		for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
			agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
		error = xfs_bwrite(mp, bp);
		if (error) {
			goto error0;
		}
		/*
		 * BNO btree root block
		 */
		bp = xfs_buf_get(mp->m_ddev_targp,
			XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
			BTOBB(mp->m_sb.sb_blocksize), 0);
		block = XFS_BUF_TO_SBLOCK(bp);
		memset(block, 0, mp->m_sb.sb_blocksize);
		block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
		block->bb_level = 0;
		block->bb_numrecs = cpu_to_be16(1);
		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
		arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
			block, 1, mp->m_alloc_mxr[0]);
		arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
		arec->ar_blockcount = cpu_to_be32(
			agsize - be32_to_cpu(arec->ar_startblock));
		error = xfs_bwrite(mp, bp);
		if (error) {
			goto error0;
		}
		/*
		 * CNT btree root block
		 */
		bp = xfs_buf_get(mp->m_ddev_targp,
			XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
			BTOBB(mp->m_sb.sb_blocksize), 0);
		block = XFS_BUF_TO_SBLOCK(bp);
		memset(block, 0, mp->m_sb.sb_blocksize);
		block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
		block->bb_level = 0;
		block->bb_numrecs = cpu_to_be16(1);
		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
		arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
			block, 1, mp->m_alloc_mxr[0]);
		arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
		arec->ar_blockcount = cpu_to_be32(
			agsize - be32_to_cpu(arec->ar_startblock));
		nfree += be32_to_cpu(arec->ar_blockcount);
		error = xfs_bwrite(mp, bp);
		if (error) {
			goto error0;
		}
		/*
		 * INO btree root block
		 */
		bp = xfs_buf_get(mp->m_ddev_targp,
			XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
			BTOBB(mp->m_sb.sb_blocksize), 0);
		block = XFS_BUF_TO_SBLOCK(bp);
		memset(block, 0, mp->m_sb.sb_blocksize);
		block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
		block->bb_level = 0;
		block->bb_numrecs = 0;
		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
		error = xfs_bwrite(mp, bp);
		if (error) {
			goto error0;
		}
	}
	xfs_trans_agblocks_delta(tp, nfree);
	/*
	 * There are new blocks in the old last a.g.
	 */
	if (new) {
		/*
		 * Change the agi length.
		 */
		error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
		if (error) {
			goto error0;
		}
		ASSERT(bp);
		agi = XFS_BUF_TO_AGI(bp);
		be32_add(&agi->agi_length, new);
		ASSERT(nagcount == oagcount ||
		       be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
		xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
		/*
		 * Change agf length.
		 */
		error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
		if (error) {
			goto error0;
		}
		ASSERT(bp);
		agf = XFS_BUF_TO_AGF(bp);
		be32_add(&agf->agf_length, new);
		ASSERT(be32_to_cpu(agf->agf_length) ==
		       be32_to_cpu(agi->agi_length));
		/*
		 * Free the new space.
		 */
		error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
			be32_to_cpu(agf->agf_length) - new), new);
		if (error) {
			goto error0;
		}
	}
	if (nagcount > oagcount)
		xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
	if (nb > mp->m_sb.sb_dblocks)
		xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
				 nb - mp->m_sb.sb_dblocks);
	if (nfree)
		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
	if (dpct)
		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
	error = xfs_trans_commit(tp, 0, NULL);
	if (error) {
		return error;
	}
	/* New allocation groups fully initialized, so update mount struct */
	if (nagimax)
		mp->m_maxagi = nagimax;
	if (mp->m_sb.sb_imax_pct) {
		__uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
		do_div(icount, 100);
		mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
	} else
		mp->m_maxicount = 0;
	for (agno = 1; agno < nagcount; agno++) {
		error = xfs_read_buf(mp, mp->m_ddev_targp,
				  XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
				  XFS_FSS_TO_BB(mp, 1), 0, &bp);
		if (error) {
			xfs_fs_cmn_err(CE_WARN, mp,
			"error %d reading secondary superblock for ag %d",
				error, agno);
			break;
		}
		sbp = XFS_BUF_TO_SBP(bp);
		xfs_xlatesb(sbp, &mp->m_sb, -1, XFS_SB_ALL_BITS);
		/*
		 * If we get an error writing out the alternate superblocks,
		 * just issue a warning and continue.  The real work is
		 * already done and committed.
		 */
		if (!(error = xfs_bwrite(mp, bp))) {
			continue;
		} else {
			xfs_fs_cmn_err(CE_WARN, mp,
		"write error %d updating secondary superblock for ag %d",
				error, agno);
			break; /* no point in continuing */
		}
	}
	return 0;

 error0:
	xfs_trans_cancel(tp, XFS_TRANS_ABORT);
	return error;
}

static int
xfs_growfs_log_private(
	xfs_mount_t		*mp,	/* mount point for filesystem */
	xfs_growfs_log_t	*in)	/* growfs log input struct */
{
	xfs_extlen_t		nb;

	nb = in->newblocks;
	if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
		return XFS_ERROR(EINVAL);
	if (nb == mp->m_sb.sb_logblocks &&
	    in->isint == (mp->m_sb.sb_logstart != 0))
		return XFS_ERROR(EINVAL);
	/*
	 * Moving the log is hard, need new interfaces to sync
	 * the log first, hold off all activity while moving it.
	 * Can have shorter or longer log in the same space,
	 * or transform internal to external log or vice versa.
	 */
	return XFS_ERROR(ENOSYS);
}

/*
 * protected versions of growfs function acquire and release locks on the mount
 * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
 * XFS_IOC_FSGROWFSRT
 */


int
xfs_growfs_data(
	xfs_mount_t		*mp,
	xfs_growfs_data_t	*in)
{
	int error;
	if (!cpsema(&mp->m_growlock))
		return XFS_ERROR(EWOULDBLOCK);
	error = xfs_growfs_data_private(mp, in);
	vsema(&mp->m_growlock);
	return error;
}

int
xfs_growfs_log(
	xfs_mount_t		*mp,
	xfs_growfs_log_t	*in)
{
	int error;
	if (!cpsema(&mp->m_growlock))
		return XFS_ERROR(EWOULDBLOCK);
	error = xfs_growfs_log_private(mp, in);
	vsema(&mp->m_growlock);
	return error;
}

/*
 * exported through ioctl XFS_IOC_FSCOUNTS
 */

int
xfs_fs_counts(
	xfs_mount_t		*mp,
	xfs_fsop_counts_t	*cnt)
{
	unsigned long	s;

	xfs_icsb_sync_counters_lazy(mp);
	s = XFS_SB_LOCK(mp);
	cnt->freedata = mp->m_sb.sb_fdblocks;
	cnt->freertx = mp->m_sb.sb_frextents;
	cnt->freeino = mp->m_sb.sb_ifree;
	cnt->allocino = mp->m_sb.sb_icount;
	XFS_SB_UNLOCK(mp, s);
	return 0;
}

/*
 * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
 *
 * xfs_reserve_blocks is called to set m_resblks
 * in the in-core mount table. The number of unused reserved blocks
 * is kept in m_resblks_avail.
 *
 * Reserve the requested number of blocks if available. Otherwise return
 * as many as possible to satisfy the request. The actual number
 * reserved are returned in outval
 *
 * A null inval pointer indicates that only the current reserved blocks
 * available  should  be returned no settings are changed.
 */

int
xfs_reserve_blocks(
	xfs_mount_t             *mp,
	__uint64_t              *inval,
	xfs_fsop_resblks_t      *outval)
{
	__int64_t		lcounter, delta;
	__uint64_t		request;
	unsigned long		s;

	/* If inval is null, report current values and return */

	if (inval == (__uint64_t *)NULL) {
		outval->resblks = mp->m_resblks;
		outval->resblks_avail = mp->m_resblks_avail;
		return 0;
	}

	request = *inval;
	s = XFS_SB_LOCK(mp);

	/*
	 * If our previous reservation was larger than the current value,
	 * then move any unused blocks back to the free pool.
	 */

	if (mp->m_resblks > request) {
		lcounter = mp->m_resblks_avail - request;
		if (lcounter  > 0) {		/* release unused blocks */
			mp->m_sb.sb_fdblocks += lcounter;
			mp->m_resblks_avail -= lcounter;
		}
		mp->m_resblks = request;
	} else {
		delta = request - mp->m_resblks;
		lcounter = mp->m_sb.sb_fdblocks - delta;
		if (lcounter < 0) {
			/* We can't satisfy the request, just get what we can */
			mp->m_resblks += mp->m_sb.sb_fdblocks;
			mp->m_resblks_avail += mp->m_sb.sb_fdblocks;
			mp->m_sb.sb_fdblocks = 0;
		} else {
			mp->m_sb.sb_fdblocks = lcounter;
			mp->m_resblks = request;
			mp->m_resblks_avail += delta;
		}
	}

	outval->resblks = mp->m_resblks;
	outval->resblks_avail = mp->m_resblks_avail;
	XFS_SB_UNLOCK(mp, s);
	return 0;
}

void
xfs_fs_log_dummy(xfs_mount_t *mp)
{
	xfs_trans_t *tp;
	xfs_inode_t *ip;


	tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
	atomic_inc(&mp->m_active_trans);
	if (xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0)) {
		xfs_trans_cancel(tp, 0);
		return;
	}

	ip = mp->m_rootip;
	xfs_ilock(ip, XFS_ILOCK_EXCL);

	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
	xfs_trans_ihold(tp, ip);
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	xfs_trans_set_sync(tp);
	xfs_trans_commit(tp, 0, NULL);

	xfs_iunlock(ip, XFS_ILOCK_EXCL);
}

int
xfs_fs_goingdown(
	xfs_mount_t	*mp,
	__uint32_t	inflags)
{
	switch (inflags) {
	case XFS_FSOP_GOING_FLAGS_DEFAULT: {
		struct bhv_vfs *vfsp = XFS_MTOVFS(mp);
		struct super_block *sb = freeze_bdev(vfsp->vfs_super->s_bdev);

		if (sb && !IS_ERR(sb)) {
			xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
			thaw_bdev(sb->s_bdev, sb);
		}
	
		break;
	}
	case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
		xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
		break;
	case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
		xfs_force_shutdown(mp,
				SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
		break;
	default:
		return XFS_ERROR(EINVAL);
	}

	return 0;
}