xref: /linux/fs/xfs/xfs_fsops.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_inum.h"
23 #include "xfs_log.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_alloc_btree.h"
32 #include "xfs_ialloc_btree.h"
33 #include "xfs_dir2_sf.h"
34 #include "xfs_attr_sf.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_inode_item.h"
38 #include "xfs_btree.h"
39 #include "xfs_error.h"
40 #include "xfs_alloc.h"
41 #include "xfs_ialloc.h"
42 #include "xfs_fsops.h"
43 #include "xfs_itable.h"
44 #include "xfs_trans_space.h"
45 #include "xfs_rtalloc.h"
46 #include "xfs_rw.h"
47 
48 /*
49  * File system operations
50  */
51 
52 int
53 xfs_fs_geometry(
54 	xfs_mount_t		*mp,
55 	xfs_fsop_geom_t		*geo,
56 	int			new_version)
57 {
58 	geo->blocksize = mp->m_sb.sb_blocksize;
59 	geo->rtextsize = mp->m_sb.sb_rextsize;
60 	geo->agblocks = mp->m_sb.sb_agblocks;
61 	geo->agcount = mp->m_sb.sb_agcount;
62 	geo->logblocks = mp->m_sb.sb_logblocks;
63 	geo->sectsize = mp->m_sb.sb_sectsize;
64 	geo->inodesize = mp->m_sb.sb_inodesize;
65 	geo->imaxpct = mp->m_sb.sb_imax_pct;
66 	geo->datablocks = mp->m_sb.sb_dblocks;
67 	geo->rtblocks = mp->m_sb.sb_rblocks;
68 	geo->rtextents = mp->m_sb.sb_rextents;
69 	geo->logstart = mp->m_sb.sb_logstart;
70 	ASSERT(sizeof(geo->uuid)==sizeof(mp->m_sb.sb_uuid));
71 	memcpy(geo->uuid, &mp->m_sb.sb_uuid, sizeof(mp->m_sb.sb_uuid));
72 	if (new_version >= 2) {
73 		geo->sunit = mp->m_sb.sb_unit;
74 		geo->swidth = mp->m_sb.sb_width;
75 	}
76 	if (new_version >= 3) {
77 		geo->version = XFS_FSOP_GEOM_VERSION;
78 		geo->flags =
79 			(XFS_SB_VERSION_HASATTR(&mp->m_sb) ?
80 				XFS_FSOP_GEOM_FLAGS_ATTR : 0) |
81 			(XFS_SB_VERSION_HASNLINK(&mp->m_sb) ?
82 				XFS_FSOP_GEOM_FLAGS_NLINK : 0) |
83 			(XFS_SB_VERSION_HASQUOTA(&mp->m_sb) ?
84 				XFS_FSOP_GEOM_FLAGS_QUOTA : 0) |
85 			(XFS_SB_VERSION_HASALIGN(&mp->m_sb) ?
86 				XFS_FSOP_GEOM_FLAGS_IALIGN : 0) |
87 			(XFS_SB_VERSION_HASDALIGN(&mp->m_sb) ?
88 				XFS_FSOP_GEOM_FLAGS_DALIGN : 0) |
89 			(XFS_SB_VERSION_HASSHARED(&mp->m_sb) ?
90 				XFS_FSOP_GEOM_FLAGS_SHARED : 0) |
91 			(XFS_SB_VERSION_HASEXTFLGBIT(&mp->m_sb) ?
92 				XFS_FSOP_GEOM_FLAGS_EXTFLG : 0) |
93 			(XFS_SB_VERSION_HASDIRV2(&mp->m_sb) ?
94 				XFS_FSOP_GEOM_FLAGS_DIRV2 : 0) |
95 			(XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
96 				XFS_FSOP_GEOM_FLAGS_SECTOR : 0) |
97 			(XFS_SB_VERSION_HASATTR2(&mp->m_sb) ?
98 				XFS_FSOP_GEOM_FLAGS_ATTR2 : 0);
99 		geo->logsectsize = XFS_SB_VERSION_HASSECTOR(&mp->m_sb) ?
100 				mp->m_sb.sb_logsectsize : BBSIZE;
101 		geo->rtsectsize = mp->m_sb.sb_blocksize;
102 		geo->dirblocksize = mp->m_dirblksize;
103 	}
104 	if (new_version >= 4) {
105 		geo->flags |=
106 			(XFS_SB_VERSION_HASLOGV2(&mp->m_sb) ?
107 				XFS_FSOP_GEOM_FLAGS_LOGV2 : 0);
108 		geo->logsunit = mp->m_sb.sb_logsunit;
109 	}
110 	return 0;
111 }
112 
113 static int
114 xfs_growfs_data_private(
115 	xfs_mount_t		*mp,		/* mount point for filesystem */
116 	xfs_growfs_data_t	*in)		/* growfs data input struct */
117 {
118 	xfs_agf_t		*agf;
119 	xfs_agi_t		*agi;
120 	xfs_agnumber_t		agno;
121 	xfs_extlen_t		agsize;
122 	xfs_extlen_t		tmpsize;
123 	xfs_alloc_rec_t		*arec;
124 	xfs_btree_sblock_t	*block;
125 	xfs_buf_t		*bp;
126 	int			bucket;
127 	int			dpct;
128 	int			error;
129 	xfs_agnumber_t		nagcount;
130 	xfs_agnumber_t		nagimax = 0;
131 	xfs_rfsblock_t		nb, nb_mod;
132 	xfs_rfsblock_t		new;
133 	xfs_rfsblock_t		nfree;
134 	xfs_agnumber_t		oagcount;
135 	int			pct;
136 	xfs_sb_t		*sbp;
137 	xfs_trans_t		*tp;
138 
139 	nb = in->newblocks;
140 	pct = in->imaxpct;
141 	if (nb < mp->m_sb.sb_dblocks || pct < 0 || pct > 100)
142 		return XFS_ERROR(EINVAL);
143 	dpct = pct - mp->m_sb.sb_imax_pct;
144 	error = xfs_read_buf(mp, mp->m_ddev_targp,
145 			XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
146 			XFS_FSS_TO_BB(mp, 1), 0, &bp);
147 	if (error)
148 		return error;
149 	ASSERT(bp);
150 	xfs_buf_relse(bp);
151 
152 	new = nb;	/* use new as a temporary here */
153 	nb_mod = do_div(new, mp->m_sb.sb_agblocks);
154 	nagcount = new + (nb_mod != 0);
155 	if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
156 		nagcount--;
157 		nb = nagcount * mp->m_sb.sb_agblocks;
158 		if (nb < mp->m_sb.sb_dblocks)
159 			return XFS_ERROR(EINVAL);
160 	}
161 	new = nb - mp->m_sb.sb_dblocks;
162 	oagcount = mp->m_sb.sb_agcount;
163 	if (nagcount > oagcount) {
164 		down_write(&mp->m_peraglock);
165 		mp->m_perag = kmem_realloc(mp->m_perag,
166 			sizeof(xfs_perag_t) * nagcount,
167 			sizeof(xfs_perag_t) * oagcount,
168 			KM_SLEEP);
169 		memset(&mp->m_perag[oagcount], 0,
170 			(nagcount - oagcount) * sizeof(xfs_perag_t));
171 		mp->m_flags |= XFS_MOUNT_32BITINODES;
172 		nagimax = xfs_initialize_perag(XFS_MTOVFS(mp), mp, nagcount);
173 		up_write(&mp->m_peraglock);
174 	}
175 	tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFS);
176 	if ((error = xfs_trans_reserve(tp, XFS_GROWFS_SPACE_RES(mp),
177 			XFS_GROWDATA_LOG_RES(mp), 0, 0, 0))) {
178 		xfs_trans_cancel(tp, 0);
179 		return error;
180 	}
181 
182 	nfree = 0;
183 	for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) {
184 		/*
185 		 * AG freelist header block
186 		 */
187 		bp = xfs_buf_get(mp->m_ddev_targp,
188 				  XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
189 				  XFS_FSS_TO_BB(mp, 1), 0);
190 		agf = XFS_BUF_TO_AGF(bp);
191 		memset(agf, 0, mp->m_sb.sb_sectsize);
192 		agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
193 		agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
194 		agf->agf_seqno = cpu_to_be32(agno);
195 		if (agno == nagcount - 1)
196 			agsize =
197 				nb -
198 				(agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
199 		else
200 			agsize = mp->m_sb.sb_agblocks;
201 		agf->agf_length = cpu_to_be32(agsize);
202 		agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
203 		agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
204 		agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
205 		agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
206 		agf->agf_flfirst = 0;
207 		agf->agf_fllast = cpu_to_be32(XFS_AGFL_SIZE(mp) - 1);
208 		agf->agf_flcount = 0;
209 		tmpsize = agsize - XFS_PREALLOC_BLOCKS(mp);
210 		agf->agf_freeblks = cpu_to_be32(tmpsize);
211 		agf->agf_longest = cpu_to_be32(tmpsize);
212 		error = xfs_bwrite(mp, bp);
213 		if (error) {
214 			goto error0;
215 		}
216 		/*
217 		 * AG inode header block
218 		 */
219 		bp = xfs_buf_get(mp->m_ddev_targp,
220 				  XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
221 				  XFS_FSS_TO_BB(mp, 1), 0);
222 		agi = XFS_BUF_TO_AGI(bp);
223 		memset(agi, 0, mp->m_sb.sb_sectsize);
224 		agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
225 		agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
226 		agi->agi_seqno = cpu_to_be32(agno);
227 		agi->agi_length = cpu_to_be32(agsize);
228 		agi->agi_count = 0;
229 		agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
230 		agi->agi_level = cpu_to_be32(1);
231 		agi->agi_freecount = 0;
232 		agi->agi_newino = cpu_to_be32(NULLAGINO);
233 		agi->agi_dirino = cpu_to_be32(NULLAGINO);
234 		for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
235 			agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
236 		error = xfs_bwrite(mp, bp);
237 		if (error) {
238 			goto error0;
239 		}
240 		/*
241 		 * BNO btree root block
242 		 */
243 		bp = xfs_buf_get(mp->m_ddev_targp,
244 			XFS_AGB_TO_DADDR(mp, agno, XFS_BNO_BLOCK(mp)),
245 			BTOBB(mp->m_sb.sb_blocksize), 0);
246 		block = XFS_BUF_TO_SBLOCK(bp);
247 		memset(block, 0, mp->m_sb.sb_blocksize);
248 		block->bb_magic = cpu_to_be32(XFS_ABTB_MAGIC);
249 		block->bb_level = 0;
250 		block->bb_numrecs = cpu_to_be16(1);
251 		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
252 		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
253 		arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
254 			block, 1, mp->m_alloc_mxr[0]);
255 		arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
256 		arec->ar_blockcount = cpu_to_be32(
257 			agsize - be32_to_cpu(arec->ar_startblock));
258 		error = xfs_bwrite(mp, bp);
259 		if (error) {
260 			goto error0;
261 		}
262 		/*
263 		 * CNT btree root block
264 		 */
265 		bp = xfs_buf_get(mp->m_ddev_targp,
266 			XFS_AGB_TO_DADDR(mp, agno, XFS_CNT_BLOCK(mp)),
267 			BTOBB(mp->m_sb.sb_blocksize), 0);
268 		block = XFS_BUF_TO_SBLOCK(bp);
269 		memset(block, 0, mp->m_sb.sb_blocksize);
270 		block->bb_magic = cpu_to_be32(XFS_ABTC_MAGIC);
271 		block->bb_level = 0;
272 		block->bb_numrecs = cpu_to_be16(1);
273 		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
274 		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
275 		arec = XFS_BTREE_REC_ADDR(mp->m_sb.sb_blocksize, xfs_alloc,
276 			block, 1, mp->m_alloc_mxr[0]);
277 		arec->ar_startblock = cpu_to_be32(XFS_PREALLOC_BLOCKS(mp));
278 		arec->ar_blockcount = cpu_to_be32(
279 			agsize - be32_to_cpu(arec->ar_startblock));
280 		nfree += be32_to_cpu(arec->ar_blockcount);
281 		error = xfs_bwrite(mp, bp);
282 		if (error) {
283 			goto error0;
284 		}
285 		/*
286 		 * INO btree root block
287 		 */
288 		bp = xfs_buf_get(mp->m_ddev_targp,
289 			XFS_AGB_TO_DADDR(mp, agno, XFS_IBT_BLOCK(mp)),
290 			BTOBB(mp->m_sb.sb_blocksize), 0);
291 		block = XFS_BUF_TO_SBLOCK(bp);
292 		memset(block, 0, mp->m_sb.sb_blocksize);
293 		block->bb_magic = cpu_to_be32(XFS_IBT_MAGIC);
294 		block->bb_level = 0;
295 		block->bb_numrecs = 0;
296 		block->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
297 		block->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
298 		error = xfs_bwrite(mp, bp);
299 		if (error) {
300 			goto error0;
301 		}
302 	}
303 	xfs_trans_agblocks_delta(tp, nfree);
304 	/*
305 	 * There are new blocks in the old last a.g.
306 	 */
307 	if (new) {
308 		/*
309 		 * Change the agi length.
310 		 */
311 		error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
312 		if (error) {
313 			goto error0;
314 		}
315 		ASSERT(bp);
316 		agi = XFS_BUF_TO_AGI(bp);
317 		be32_add(&agi->agi_length, new);
318 		ASSERT(nagcount == oagcount ||
319 		       be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
320 		xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
321 		/*
322 		 * Change agf length.
323 		 */
324 		error = xfs_alloc_read_agf(mp, tp, agno, 0, &bp);
325 		if (error) {
326 			goto error0;
327 		}
328 		ASSERT(bp);
329 		agf = XFS_BUF_TO_AGF(bp);
330 		be32_add(&agf->agf_length, new);
331 		ASSERT(be32_to_cpu(agf->agf_length) ==
332 		       be32_to_cpu(agi->agi_length));
333 		/*
334 		 * Free the new space.
335 		 */
336 		error = xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, agno,
337 			be32_to_cpu(agf->agf_length) - new), new);
338 		if (error) {
339 			goto error0;
340 		}
341 	}
342 	if (nagcount > oagcount)
343 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
344 	if (nb > mp->m_sb.sb_dblocks)
345 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
346 				 nb - mp->m_sb.sb_dblocks);
347 	if (nfree)
348 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, nfree);
349 	if (dpct)
350 		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
351 	error = xfs_trans_commit(tp, 0, NULL);
352 	if (error) {
353 		return error;
354 	}
355 	/* New allocation groups fully initialized, so update mount struct */
356 	if (nagimax)
357 		mp->m_maxagi = nagimax;
358 	if (mp->m_sb.sb_imax_pct) {
359 		__uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
360 		do_div(icount, 100);
361 		mp->m_maxicount = icount << mp->m_sb.sb_inopblog;
362 	} else
363 		mp->m_maxicount = 0;
364 	for (agno = 1; agno < nagcount; agno++) {
365 		error = xfs_read_buf(mp, mp->m_ddev_targp,
366 				  XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
367 				  XFS_FSS_TO_BB(mp, 1), 0, &bp);
368 		if (error) {
369 			xfs_fs_cmn_err(CE_WARN, mp,
370 			"error %d reading secondary superblock for ag %d",
371 				error, agno);
372 			break;
373 		}
374 		sbp = XFS_BUF_TO_SBP(bp);
375 		xfs_xlatesb(sbp, &mp->m_sb, -1, XFS_SB_ALL_BITS);
376 		/*
377 		 * If we get an error writing out the alternate superblocks,
378 		 * just issue a warning and continue.  The real work is
379 		 * already done and committed.
380 		 */
381 		if (!(error = xfs_bwrite(mp, bp))) {
382 			continue;
383 		} else {
384 			xfs_fs_cmn_err(CE_WARN, mp,
385 		"write error %d updating secondary superblock for ag %d",
386 				error, agno);
387 			break; /* no point in continuing */
388 		}
389 	}
390 	return 0;
391 
392  error0:
393 	xfs_trans_cancel(tp, XFS_TRANS_ABORT);
394 	return error;
395 }
396 
397 static int
398 xfs_growfs_log_private(
399 	xfs_mount_t		*mp,	/* mount point for filesystem */
400 	xfs_growfs_log_t	*in)	/* growfs log input struct */
401 {
402 	xfs_extlen_t		nb;
403 
404 	nb = in->newblocks;
405 	if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
406 		return XFS_ERROR(EINVAL);
407 	if (nb == mp->m_sb.sb_logblocks &&
408 	    in->isint == (mp->m_sb.sb_logstart != 0))
409 		return XFS_ERROR(EINVAL);
410 	/*
411 	 * Moving the log is hard, need new interfaces to sync
412 	 * the log first, hold off all activity while moving it.
413 	 * Can have shorter or longer log in the same space,
414 	 * or transform internal to external log or vice versa.
415 	 */
416 	return XFS_ERROR(ENOSYS);
417 }
418 
419 /*
420  * protected versions of growfs function acquire and release locks on the mount
421  * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
422  * XFS_IOC_FSGROWFSRT
423  */
424 
425 
426 int
427 xfs_growfs_data(
428 	xfs_mount_t		*mp,
429 	xfs_growfs_data_t	*in)
430 {
431 	int error;
432 	if (!cpsema(&mp->m_growlock))
433 		return XFS_ERROR(EWOULDBLOCK);
434 	error = xfs_growfs_data_private(mp, in);
435 	vsema(&mp->m_growlock);
436 	return error;
437 }
438 
439 int
440 xfs_growfs_log(
441 	xfs_mount_t		*mp,
442 	xfs_growfs_log_t	*in)
443 {
444 	int error;
445 	if (!cpsema(&mp->m_growlock))
446 		return XFS_ERROR(EWOULDBLOCK);
447 	error = xfs_growfs_log_private(mp, in);
448 	vsema(&mp->m_growlock);
449 	return error;
450 }
451 
452 /*
453  * exported through ioctl XFS_IOC_FSCOUNTS
454  */
455 
456 int
457 xfs_fs_counts(
458 	xfs_mount_t		*mp,
459 	xfs_fsop_counts_t	*cnt)
460 {
461 	unsigned long	s;
462 
463 	xfs_icsb_sync_counters_lazy(mp);
464 	s = XFS_SB_LOCK(mp);
465 	cnt->freedata = mp->m_sb.sb_fdblocks;
466 	cnt->freertx = mp->m_sb.sb_frextents;
467 	cnt->freeino = mp->m_sb.sb_ifree;
468 	cnt->allocino = mp->m_sb.sb_icount;
469 	XFS_SB_UNLOCK(mp, s);
470 	return 0;
471 }
472 
473 /*
474  * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
475  *
476  * xfs_reserve_blocks is called to set m_resblks
477  * in the in-core mount table. The number of unused reserved blocks
478  * is kept in m_resblks_avail.
479  *
480  * Reserve the requested number of blocks if available. Otherwise return
481  * as many as possible to satisfy the request. The actual number
482  * reserved are returned in outval
483  *
484  * A null inval pointer indicates that only the current reserved blocks
485  * available  should  be returned no settings are changed.
486  */
487 
488 int
489 xfs_reserve_blocks(
490 	xfs_mount_t             *mp,
491 	__uint64_t              *inval,
492 	xfs_fsop_resblks_t      *outval)
493 {
494 	__int64_t		lcounter, delta;
495 	__uint64_t		request;
496 	unsigned long		s;
497 
498 	/* If inval is null, report current values and return */
499 
500 	if (inval == (__uint64_t *)NULL) {
501 		outval->resblks = mp->m_resblks;
502 		outval->resblks_avail = mp->m_resblks_avail;
503 		return 0;
504 	}
505 
506 	request = *inval;
507 	s = XFS_SB_LOCK(mp);
508 
509 	/*
510 	 * If our previous reservation was larger than the current value,
511 	 * then move any unused blocks back to the free pool.
512 	 */
513 
514 	if (mp->m_resblks > request) {
515 		lcounter = mp->m_resblks_avail - request;
516 		if (lcounter  > 0) {		/* release unused blocks */
517 			mp->m_sb.sb_fdblocks += lcounter;
518 			mp->m_resblks_avail -= lcounter;
519 		}
520 		mp->m_resblks = request;
521 	} else {
522 		delta = request - mp->m_resblks;
523 		lcounter = mp->m_sb.sb_fdblocks - delta;
524 		if (lcounter < 0) {
525 			/* We can't satisfy the request, just get what we can */
526 			mp->m_resblks += mp->m_sb.sb_fdblocks;
527 			mp->m_resblks_avail += mp->m_sb.sb_fdblocks;
528 			mp->m_sb.sb_fdblocks = 0;
529 		} else {
530 			mp->m_sb.sb_fdblocks = lcounter;
531 			mp->m_resblks = request;
532 			mp->m_resblks_avail += delta;
533 		}
534 	}
535 
536 	outval->resblks = mp->m_resblks;
537 	outval->resblks_avail = mp->m_resblks_avail;
538 	XFS_SB_UNLOCK(mp, s);
539 	return 0;
540 }
541 
542 void
543 xfs_fs_log_dummy(
544 	xfs_mount_t	*mp)
545 {
546 	xfs_trans_t	*tp;
547 	xfs_inode_t	*ip;
548 
549 	tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
550 	if (xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0)) {
551 		xfs_trans_cancel(tp, 0);
552 		return;
553 	}
554 
555 	ip = mp->m_rootip;
556 	xfs_ilock(ip, XFS_ILOCK_EXCL);
557 
558 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
559 	xfs_trans_ihold(tp, ip);
560 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
561 	xfs_trans_set_sync(tp);
562 	xfs_trans_commit(tp, 0, NULL);
563 
564 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
565 }
566 
567 int
568 xfs_fs_goingdown(
569 	xfs_mount_t	*mp,
570 	__uint32_t	inflags)
571 {
572 	switch (inflags) {
573 	case XFS_FSOP_GOING_FLAGS_DEFAULT: {
574 		struct bhv_vfs *vfsp = XFS_MTOVFS(mp);
575 		struct super_block *sb = freeze_bdev(vfsp->vfs_super->s_bdev);
576 
577 		if (sb && !IS_ERR(sb)) {
578 			xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
579 			thaw_bdev(sb->s_bdev, sb);
580 		}
581 
582 		break;
583 	}
584 	case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
585 		xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
586 		break;
587 	case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
588 		xfs_force_shutdown(mp,
589 				SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
590 		break;
591 	default:
592 		return XFS_ERROR(EINVAL);
593 	}
594 
595 	return 0;
596 }
597