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  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
  4 * Copyright (c) 2018 Red Hat, Inc.
  5 * All rights reserved.
  6 */
  7
  8#include "xfs.h"
  9#include "xfs_fs.h"
 10#include "xfs_shared.h"
 11#include "xfs_format.h"
 12#include "xfs_trans_resv.h"
 13#include "xfs_bit.h"
 14#include "xfs_sb.h"
 15#include "xfs_mount.h"
 16#include "xfs_btree.h"
 17#include "xfs_alloc_btree.h"
 18#include "xfs_rmap_btree.h"
 19#include "xfs_alloc.h"
 20#include "xfs_ialloc.h"
 21#include "xfs_rmap.h"
 22#include "xfs_ag.h"
 23#include "xfs_ag_resv.h"
 24#include "xfs_health.h"
 25
 26static int
 27xfs_get_aghdr_buf(
 28	struct xfs_mount	*mp,
 29	xfs_daddr_t		blkno,
 30	size_t			numblks,
 31	struct xfs_buf		**bpp,
 32	const struct xfs_buf_ops *ops)
 33{
 34	struct xfs_buf		*bp;
 35	int			error;
 36
 37	error = xfs_buf_get_uncached(mp->m_ddev_targp, numblks, 0, &bp);
 38	if (error)
 39		return error;
 40
 41	xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
 42	bp->b_bn = blkno;
 43	bp->b_maps[0].bm_bn = blkno;
 44	bp->b_ops = ops;
 45
 46	*bpp = bp;
 47	return 0;
 48}
 49
 50static inline bool is_log_ag(struct xfs_mount *mp, struct aghdr_init_data *id)
 51{
 52	return mp->m_sb.sb_logstart > 0 &&
 53	       id->agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
 54}
 55
 56/*
 57 * Generic btree root block init function
 58 */
 59static void
 60xfs_btroot_init(
 61	struct xfs_mount	*mp,
 62	struct xfs_buf		*bp,
 63	struct aghdr_init_data	*id)
 64{
 65	xfs_btree_init_block(mp, bp, id->type, 0, 0, id->agno);
 66}
 67
 68/* Finish initializing a free space btree. */
 69static void
 70xfs_freesp_init_recs(
 71	struct xfs_mount	*mp,
 72	struct xfs_buf		*bp,
 73	struct aghdr_init_data	*id)
 74{
 75	struct xfs_alloc_rec	*arec;
 76	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
 77
 78	arec = XFS_ALLOC_REC_ADDR(mp, XFS_BUF_TO_BLOCK(bp), 1);
 79	arec->ar_startblock = cpu_to_be32(mp->m_ag_prealloc_blocks);
 80
 81	if (is_log_ag(mp, id)) {
 82		struct xfs_alloc_rec	*nrec;
 83		xfs_agblock_t		start = XFS_FSB_TO_AGBNO(mp,
 84							mp->m_sb.sb_logstart);
 85
 86		ASSERT(start >= mp->m_ag_prealloc_blocks);
 87		if (start != mp->m_ag_prealloc_blocks) {
 88			/*
 89			 * Modify first record to pad stripe align of log
 90			 */
 91			arec->ar_blockcount = cpu_to_be32(start -
 92						mp->m_ag_prealloc_blocks);
 93			nrec = arec + 1;
 94
 95			/*
 96			 * Insert second record at start of internal log
 97			 * which then gets trimmed.
 98			 */
 99			nrec->ar_startblock = cpu_to_be32(
100					be32_to_cpu(arec->ar_startblock) +
101					be32_to_cpu(arec->ar_blockcount));
102			arec = nrec;
103			be16_add_cpu(&block->bb_numrecs, 1);
104		}
105		/*
106		 * Change record start to after the internal log
107		 */
108		be32_add_cpu(&arec->ar_startblock, mp->m_sb.sb_logblocks);
109	}
110
111	/*
112	 * Calculate the record block count and check for the case where
113	 * the log might have consumed all available space in the AG. If
114	 * so, reset the record count to 0 to avoid exposure of an invalid
115	 * record start block.
116	 */
117	arec->ar_blockcount = cpu_to_be32(id->agsize -
118					  be32_to_cpu(arec->ar_startblock));
119	if (!arec->ar_blockcount)
120		block->bb_numrecs = 0;
121}
122
123/*
124 * Alloc btree root block init functions
125 */
126static void
127xfs_bnoroot_init(
128	struct xfs_mount	*mp,
129	struct xfs_buf		*bp,
130	struct aghdr_init_data	*id)
131{
132	xfs_btree_init_block(mp, bp, XFS_BTNUM_BNO, 0, 1, id->agno);
133	xfs_freesp_init_recs(mp, bp, id);
134}
135
136static void
137xfs_cntroot_init(
138	struct xfs_mount	*mp,
139	struct xfs_buf		*bp,
140	struct aghdr_init_data	*id)
141{
142	xfs_btree_init_block(mp, bp, XFS_BTNUM_CNT, 0, 1, id->agno);
143	xfs_freesp_init_recs(mp, bp, id);
144}
145
146/*
147 * Reverse map root block init
148 */
149static void
150xfs_rmaproot_init(
151	struct xfs_mount	*mp,
152	struct xfs_buf		*bp,
153	struct aghdr_init_data	*id)
154{
155	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
156	struct xfs_rmap_rec	*rrec;
157
158	xfs_btree_init_block(mp, bp, XFS_BTNUM_RMAP, 0, 4, id->agno);
159
160	/*
161	 * mark the AG header regions as static metadata The BNO
162	 * btree block is the first block after the headers, so
163	 * it's location defines the size of region the static
164	 * metadata consumes.
165	 *
166	 * Note: unlike mkfs, we never have to account for log
167	 * space when growing the data regions
168	 */
169	rrec = XFS_RMAP_REC_ADDR(block, 1);
170	rrec->rm_startblock = 0;
171	rrec->rm_blockcount = cpu_to_be32(XFS_BNO_BLOCK(mp));
172	rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_FS);
173	rrec->rm_offset = 0;
174
175	/* account freespace btree root blocks */
176	rrec = XFS_RMAP_REC_ADDR(block, 2);
177	rrec->rm_startblock = cpu_to_be32(XFS_BNO_BLOCK(mp));
178	rrec->rm_blockcount = cpu_to_be32(2);
179	rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
180	rrec->rm_offset = 0;
181
182	/* account inode btree root blocks */
183	rrec = XFS_RMAP_REC_ADDR(block, 3);
184	rrec->rm_startblock = cpu_to_be32(XFS_IBT_BLOCK(mp));
185	rrec->rm_blockcount = cpu_to_be32(XFS_RMAP_BLOCK(mp) -
186					  XFS_IBT_BLOCK(mp));
187	rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_INOBT);
188	rrec->rm_offset = 0;
189
190	/* account for rmap btree root */
191	rrec = XFS_RMAP_REC_ADDR(block, 4);
192	rrec->rm_startblock = cpu_to_be32(XFS_RMAP_BLOCK(mp));
193	rrec->rm_blockcount = cpu_to_be32(1);
194	rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_AG);
195	rrec->rm_offset = 0;
196
197	/* account for refc btree root */
198	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
199		rrec = XFS_RMAP_REC_ADDR(block, 5);
200		rrec->rm_startblock = cpu_to_be32(xfs_refc_block(mp));
201		rrec->rm_blockcount = cpu_to_be32(1);
202		rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_REFC);
203		rrec->rm_offset = 0;
204		be16_add_cpu(&block->bb_numrecs, 1);
205	}
206
207	/* account for the log space */
208	if (is_log_ag(mp, id)) {
209		rrec = XFS_RMAP_REC_ADDR(block,
210				be16_to_cpu(block->bb_numrecs) + 1);
211		rrec->rm_startblock = cpu_to_be32(
212				XFS_FSB_TO_AGBNO(mp, mp->m_sb.sb_logstart));
213		rrec->rm_blockcount = cpu_to_be32(mp->m_sb.sb_logblocks);
214		rrec->rm_owner = cpu_to_be64(XFS_RMAP_OWN_LOG);
215		rrec->rm_offset = 0;
216		be16_add_cpu(&block->bb_numrecs, 1);
217	}
218}
219
220/*
221 * Initialise new secondary superblocks with the pre-grow geometry, but mark
222 * them as "in progress" so we know they haven't yet been activated. This will
223 * get cleared when the update with the new geometry information is done after
224 * changes to the primary are committed. This isn't strictly necessary, but we
225 * get it for free with the delayed buffer write lists and it means we can tell
226 * if a grow operation didn't complete properly after the fact.
227 */
228static void
229xfs_sbblock_init(
230	struct xfs_mount	*mp,
231	struct xfs_buf		*bp,
232	struct aghdr_init_data	*id)
233{
234	struct xfs_dsb		*dsb = bp->b_addr;
235
236	xfs_sb_to_disk(dsb, &mp->m_sb);
237	dsb->sb_inprogress = 1;
238}
239
240static void
241xfs_agfblock_init(
242	struct xfs_mount	*mp,
243	struct xfs_buf		*bp,
244	struct aghdr_init_data	*id)
245{
246	struct xfs_agf		*agf = bp->b_addr;
247	xfs_extlen_t		tmpsize;
248
249	agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
250	agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
251	agf->agf_seqno = cpu_to_be32(id->agno);
252	agf->agf_length = cpu_to_be32(id->agsize);
253	agf->agf_roots[XFS_BTNUM_BNOi] = cpu_to_be32(XFS_BNO_BLOCK(mp));
254	agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(XFS_CNT_BLOCK(mp));
255	agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(1);
256	agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(1);
257	if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
258		agf->agf_roots[XFS_BTNUM_RMAPi] =
259					cpu_to_be32(XFS_RMAP_BLOCK(mp));
260		agf->agf_levels[XFS_BTNUM_RMAPi] = cpu_to_be32(1);
261		agf->agf_rmap_blocks = cpu_to_be32(1);
262	}
263
264	agf->agf_flfirst = cpu_to_be32(1);
265	agf->agf_fllast = 0;
266	agf->agf_flcount = 0;
267	tmpsize = id->agsize - mp->m_ag_prealloc_blocks;
268	agf->agf_freeblks = cpu_to_be32(tmpsize);
269	agf->agf_longest = cpu_to_be32(tmpsize);
270	if (xfs_sb_version_hascrc(&mp->m_sb))
271		uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
272	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
273		agf->agf_refcount_root = cpu_to_be32(
274				xfs_refc_block(mp));
275		agf->agf_refcount_level = cpu_to_be32(1);
276		agf->agf_refcount_blocks = cpu_to_be32(1);
277	}
278
279	if (is_log_ag(mp, id)) {
280		int64_t	logblocks = mp->m_sb.sb_logblocks;
281
282		be32_add_cpu(&agf->agf_freeblks, -logblocks);
283		agf->agf_longest = cpu_to_be32(id->agsize -
284			XFS_FSB_TO_AGBNO(mp, mp->m_sb.sb_logstart) - logblocks);
285	}
286}
287
288static void
289xfs_agflblock_init(
290	struct xfs_mount	*mp,
291	struct xfs_buf		*bp,
292	struct aghdr_init_data	*id)
293{
294	struct xfs_agfl		*agfl = XFS_BUF_TO_AGFL(bp);
295	__be32			*agfl_bno;
296	int			bucket;
297
298	if (xfs_sb_version_hascrc(&mp->m_sb)) {
299		agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
300		agfl->agfl_seqno = cpu_to_be32(id->agno);
301		uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid);
302	}
303
304	agfl_bno = xfs_buf_to_agfl_bno(bp);
305	for (bucket = 0; bucket < xfs_agfl_size(mp); bucket++)
306		agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
307}
308
309static void
310xfs_agiblock_init(
311	struct xfs_mount	*mp,
312	struct xfs_buf		*bp,
313	struct aghdr_init_data	*id)
314{
315	struct xfs_agi		*agi = bp->b_addr;
316	int			bucket;
317
318	agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);
319	agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);
320	agi->agi_seqno = cpu_to_be32(id->agno);
321	agi->agi_length = cpu_to_be32(id->agsize);
322	agi->agi_count = 0;
323	agi->agi_root = cpu_to_be32(XFS_IBT_BLOCK(mp));
324	agi->agi_level = cpu_to_be32(1);
325	agi->agi_freecount = 0;
326	agi->agi_newino = cpu_to_be32(NULLAGINO);
327	agi->agi_dirino = cpu_to_be32(NULLAGINO);
328	if (xfs_sb_version_hascrc(&mp->m_sb))
329		uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
330	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
331		agi->agi_free_root = cpu_to_be32(XFS_FIBT_BLOCK(mp));
332		agi->agi_free_level = cpu_to_be32(1);
333	}
334	for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)
335		agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
336}
337
338typedef void (*aghdr_init_work_f)(struct xfs_mount *mp, struct xfs_buf *bp,
339				  struct aghdr_init_data *id);
340static int
341xfs_ag_init_hdr(
342	struct xfs_mount	*mp,
343	struct aghdr_init_data	*id,
344	aghdr_init_work_f	work,
345	const struct xfs_buf_ops *ops)
346{
347	struct xfs_buf		*bp;
348	int			error;
349
350	error = xfs_get_aghdr_buf(mp, id->daddr, id->numblks, &bp, ops);
351	if (error)
352		return error;
353
354	(*work)(mp, bp, id);
355
356	xfs_buf_delwri_queue(bp, &id->buffer_list);
357	xfs_buf_relse(bp);
358	return 0;
359}
360
361struct xfs_aghdr_grow_data {
362	xfs_daddr_t		daddr;
363	size_t			numblks;
364	const struct xfs_buf_ops *ops;
365	aghdr_init_work_f	work;
366	xfs_btnum_t		type;
367	bool			need_init;
368};
369
370/*
371 * Prepare new AG headers to be written to disk. We use uncached buffers here,
372 * as it is assumed these new AG headers are currently beyond the currently
373 * valid filesystem address space. Using cached buffers would trip over EOFS
374 * corruption detection alogrithms in the buffer cache lookup routines.
375 *
376 * This is a non-transactional function, but the prepared buffers are added to a
377 * delayed write buffer list supplied by the caller so they can submit them to
378 * disk and wait on them as required.
379 */
380int
381xfs_ag_init_headers(
382	struct xfs_mount	*mp,
383	struct aghdr_init_data	*id)
384
385{
386	struct xfs_aghdr_grow_data aghdr_data[] = {
387	{ /* SB */
388		.daddr = XFS_AG_DADDR(mp, id->agno, XFS_SB_DADDR),
389		.numblks = XFS_FSS_TO_BB(mp, 1),
390		.ops = &xfs_sb_buf_ops,
391		.work = &xfs_sbblock_init,
392		.need_init = true
393	},
394	{ /* AGF */
395		.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGF_DADDR(mp)),
396		.numblks = XFS_FSS_TO_BB(mp, 1),
397		.ops = &xfs_agf_buf_ops,
398		.work = &xfs_agfblock_init,
399		.need_init = true
400	},
401	{ /* AGFL */
402		.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGFL_DADDR(mp)),
403		.numblks = XFS_FSS_TO_BB(mp, 1),
404		.ops = &xfs_agfl_buf_ops,
405		.work = &xfs_agflblock_init,
406		.need_init = true
407	},
408	{ /* AGI */
409		.daddr = XFS_AG_DADDR(mp, id->agno, XFS_AGI_DADDR(mp)),
410		.numblks = XFS_FSS_TO_BB(mp, 1),
411		.ops = &xfs_agi_buf_ops,
412		.work = &xfs_agiblock_init,
413		.need_init = true
414	},
415	{ /* BNO root block */
416		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_BNO_BLOCK(mp)),
417		.numblks = BTOBB(mp->m_sb.sb_blocksize),
418		.ops = &xfs_bnobt_buf_ops,
419		.work = &xfs_bnoroot_init,
420		.need_init = true
421	},
422	{ /* CNT root block */
423		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_CNT_BLOCK(mp)),
424		.numblks = BTOBB(mp->m_sb.sb_blocksize),
425		.ops = &xfs_cntbt_buf_ops,
426		.work = &xfs_cntroot_init,
427		.need_init = true
428	},
429	{ /* INO root block */
430		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_IBT_BLOCK(mp)),
431		.numblks = BTOBB(mp->m_sb.sb_blocksize),
432		.ops = &xfs_inobt_buf_ops,
433		.work = &xfs_btroot_init,
434		.type = XFS_BTNUM_INO,
435		.need_init = true
436	},
437	{ /* FINO root block */
438		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_FIBT_BLOCK(mp)),
439		.numblks = BTOBB(mp->m_sb.sb_blocksize),
440		.ops = &xfs_finobt_buf_ops,
441		.work = &xfs_btroot_init,
442		.type = XFS_BTNUM_FINO,
443		.need_init =  xfs_sb_version_hasfinobt(&mp->m_sb)
444	},
445	{ /* RMAP root block */
446		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, XFS_RMAP_BLOCK(mp)),
447		.numblks = BTOBB(mp->m_sb.sb_blocksize),
448		.ops = &xfs_rmapbt_buf_ops,
449		.work = &xfs_rmaproot_init,
450		.need_init = xfs_sb_version_hasrmapbt(&mp->m_sb)
451	},
452	{ /* REFC root block */
453		.daddr = XFS_AGB_TO_DADDR(mp, id->agno, xfs_refc_block(mp)),
454		.numblks = BTOBB(mp->m_sb.sb_blocksize),
455		.ops = &xfs_refcountbt_buf_ops,
456		.work = &xfs_btroot_init,
457		.type = XFS_BTNUM_REFC,
458		.need_init = xfs_sb_version_hasreflink(&mp->m_sb)
459	},
460	{ /* NULL terminating block */
461		.daddr = XFS_BUF_DADDR_NULL,
462	}
463	};
464	struct  xfs_aghdr_grow_data *dp;
465	int			error = 0;
466
467	/* Account for AG free space in new AG */
468	id->nfree += id->agsize - mp->m_ag_prealloc_blocks;
469	for (dp = &aghdr_data[0]; dp->daddr != XFS_BUF_DADDR_NULL; dp++) {
470		if (!dp->need_init)
471			continue;
472
473		id->daddr = dp->daddr;
474		id->numblks = dp->numblks;
475		id->type = dp->type;
476		error = xfs_ag_init_hdr(mp, id, dp->work, dp->ops);
477		if (error)
478			break;
479	}
480	return error;
481}
482
483/*
484 * Extent the AG indicated by the @id by the length passed in
485 */
486int
487xfs_ag_extend_space(
488	struct xfs_mount	*mp,
489	struct xfs_trans	*tp,
490	struct aghdr_init_data	*id,
491	xfs_extlen_t		len)
492{
493	struct xfs_buf		*bp;
494	struct xfs_agi		*agi;
495	struct xfs_agf		*agf;
496	int			error;
497
498	/*
499	 * Change the agi length.
500	 */
501	error = xfs_ialloc_read_agi(mp, tp, id->agno, &bp);
502	if (error)
503		return error;
504
505	agi = bp->b_addr;
506	be32_add_cpu(&agi->agi_length, len);
507	ASSERT(id->agno == mp->m_sb.sb_agcount - 1 ||
508	       be32_to_cpu(agi->agi_length) == mp->m_sb.sb_agblocks);
509	xfs_ialloc_log_agi(tp, bp, XFS_AGI_LENGTH);
510
511	/*
512	 * Change agf length.
513	 */
514	error = xfs_alloc_read_agf(mp, tp, id->agno, 0, &bp);
515	if (error)
516		return error;
517
518	agf = bp->b_addr;
519	be32_add_cpu(&agf->agf_length, len);
520	ASSERT(agf->agf_length == agi->agi_length);
521	xfs_alloc_log_agf(tp, bp, XFS_AGF_LENGTH);
522
523	/*
524	 * Free the new space.
525	 *
526	 * XFS_RMAP_OINFO_SKIP_UPDATE is used here to tell the rmap btree that
527	 * this doesn't actually exist in the rmap btree.
528	 */
529	error = xfs_rmap_free(tp, bp, id->agno,
530				be32_to_cpu(agf->agf_length) - len,
531				len, &XFS_RMAP_OINFO_SKIP_UPDATE);
532	if (error)
533		return error;
534
535	return  xfs_free_extent(tp, XFS_AGB_TO_FSB(mp, id->agno,
536					be32_to_cpu(agf->agf_length) - len),
537				len, &XFS_RMAP_OINFO_SKIP_UPDATE,
538				XFS_AG_RESV_NONE);
539}
540
541/* Retrieve AG geometry. */
542int
543xfs_ag_get_geometry(
544	struct xfs_mount	*mp,
545	xfs_agnumber_t		agno,
546	struct xfs_ag_geometry	*ageo)
547{
548	struct xfs_buf		*agi_bp;
549	struct xfs_buf		*agf_bp;
550	struct xfs_agi		*agi;
551	struct xfs_agf		*agf;
552	struct xfs_perag	*pag;
553	unsigned int		freeblks;
554	int			error;
555
556	if (agno >= mp->m_sb.sb_agcount)
557		return -EINVAL;
558
559	/* Lock the AG headers. */
560	error = xfs_ialloc_read_agi(mp, NULL, agno, &agi_bp);
561	if (error)
562		return error;
563	error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agf_bp);
564	if (error)
565		goto out_agi;
566
567	pag = agi_bp->b_pag;
568
569	/* Fill out form. */
570	memset(ageo, 0, sizeof(*ageo));
571	ageo->ag_number = agno;
572
573	agi = agi_bp->b_addr;
574	ageo->ag_icount = be32_to_cpu(agi->agi_count);
575	ageo->ag_ifree = be32_to_cpu(agi->agi_freecount);
576
577	agf = agf_bp->b_addr;
578	ageo->ag_length = be32_to_cpu(agf->agf_length);
579	freeblks = pag->pagf_freeblks +
580		   pag->pagf_flcount +
581		   pag->pagf_btreeblks -
582		   xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE);
583	ageo->ag_freeblks = freeblks;
584	xfs_ag_geom_health(pag, ageo);
585
586	/* Release resources. */
587	xfs_buf_relse(agf_bp);
588out_agi:
589	xfs_buf_relse(agi_bp);
590	return error;
591}